xref: /freebsd/contrib/llvm-project/llvm/lib/Target/Mips/MipsISelLowering.cpp (revision e64bea71c21eb42e97aa615188ba91f6cce0d36d)
1 //===- MipsISelLowering.cpp - Mips DAG Lowering Implementation ------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file defines the interfaces that Mips uses to lower LLVM code into a
10 // selection DAG.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "MipsISelLowering.h"
15 #include "MCTargetDesc/MipsBaseInfo.h"
16 #include "MCTargetDesc/MipsInstPrinter.h"
17 #include "MCTargetDesc/MipsMCTargetDesc.h"
18 #include "MipsCCState.h"
19 #include "MipsInstrInfo.h"
20 #include "MipsMachineFunction.h"
21 #include "MipsRegisterInfo.h"
22 #include "MipsSubtarget.h"
23 #include "MipsTargetMachine.h"
24 #include "MipsTargetObjectFile.h"
25 #include "llvm/ADT/APFloat.h"
26 #include "llvm/ADT/ArrayRef.h"
27 #include "llvm/ADT/SmallVector.h"
28 #include "llvm/ADT/Statistic.h"
29 #include "llvm/ADT/StringRef.h"
30 #include "llvm/ADT/StringSwitch.h"
31 #include "llvm/CodeGen/CallingConvLower.h"
32 #include "llvm/CodeGen/FunctionLoweringInfo.h"
33 #include "llvm/CodeGen/ISDOpcodes.h"
34 #include "llvm/CodeGen/MachineBasicBlock.h"
35 #include "llvm/CodeGen/MachineFrameInfo.h"
36 #include "llvm/CodeGen/MachineFunction.h"
37 #include "llvm/CodeGen/MachineInstr.h"
38 #include "llvm/CodeGen/MachineInstrBuilder.h"
39 #include "llvm/CodeGen/MachineJumpTableInfo.h"
40 #include "llvm/CodeGen/MachineMemOperand.h"
41 #include "llvm/CodeGen/MachineOperand.h"
42 #include "llvm/CodeGen/MachineRegisterInfo.h"
43 #include "llvm/CodeGen/SelectionDAG.h"
44 #include "llvm/CodeGen/SelectionDAGNodes.h"
45 #include "llvm/CodeGen/TargetFrameLowering.h"
46 #include "llvm/CodeGen/TargetInstrInfo.h"
47 #include "llvm/CodeGen/TargetRegisterInfo.h"
48 #include "llvm/CodeGen/ValueTypes.h"
49 #include "llvm/CodeGenTypes/MachineValueType.h"
50 #include "llvm/IR/CallingConv.h"
51 #include "llvm/IR/Constants.h"
52 #include "llvm/IR/DataLayout.h"
53 #include "llvm/IR/DebugLoc.h"
54 #include "llvm/IR/DerivedTypes.h"
55 #include "llvm/IR/Function.h"
56 #include "llvm/IR/GlobalValue.h"
57 #include "llvm/IR/Module.h"
58 #include "llvm/IR/Type.h"
59 #include "llvm/IR/Value.h"
60 #include "llvm/MC/MCContext.h"
61 #include "llvm/Support/Casting.h"
62 #include "llvm/Support/CodeGen.h"
63 #include "llvm/Support/CommandLine.h"
64 #include "llvm/Support/Compiler.h"
65 #include "llvm/Support/ErrorHandling.h"
66 #include "llvm/Support/MathExtras.h"
67 #include "llvm/Target/TargetMachine.h"
68 #include "llvm/Target/TargetOptions.h"
69 #include <algorithm>
70 #include <cassert>
71 #include <cctype>
72 #include <cstdint>
73 #include <deque>
74 #include <iterator>
75 #include <utility>
76 #include <vector>
77 
78 using namespace llvm;
79 
80 #define DEBUG_TYPE "mips-lower"
81 
82 STATISTIC(NumTailCalls, "Number of tail calls");
83 
84 static cl::opt<bool>
85 NoZeroDivCheck("mno-check-zero-division", cl::Hidden,
86                cl::desc("MIPS: Don't trap on integer division by zero."),
87                cl::init(false));
88 
89 extern cl::opt<bool> EmitJalrReloc;
90 
91 static const MCPhysReg Mips64DPRegs[8] = {
92   Mips::D12_64, Mips::D13_64, Mips::D14_64, Mips::D15_64,
93   Mips::D16_64, Mips::D17_64, Mips::D18_64, Mips::D19_64
94 };
95 
96 // The MIPS MSA ABI passes vector arguments in the integer register set.
97 // The number of integer registers used is dependant on the ABI used.
getRegisterTypeForCallingConv(LLVMContext & Context,CallingConv::ID CC,EVT VT) const98 MVT MipsTargetLowering::getRegisterTypeForCallingConv(LLVMContext &Context,
99                                                       CallingConv::ID CC,
100                                                       EVT VT) const {
101   if (!VT.isVector())
102     return getRegisterType(Context, VT);
103 
104   if (VT.isPow2VectorType() && VT.getVectorElementType().isRound())
105     return Subtarget.isABI_O32() || VT.getSizeInBits() == 32 ? MVT::i32
106                                                              : MVT::i64;
107   return getRegisterType(Context, VT.getVectorElementType());
108 }
109 
getNumRegistersForCallingConv(LLVMContext & Context,CallingConv::ID CC,EVT VT) const110 unsigned MipsTargetLowering::getNumRegistersForCallingConv(LLVMContext &Context,
111                                                            CallingConv::ID CC,
112                                                            EVT VT) const {
113   if (VT.isVector()) {
114     if (VT.isPow2VectorType() && VT.getVectorElementType().isRound())
115       return divideCeil(VT.getSizeInBits(), Subtarget.isABI_O32() ? 32 : 64);
116     return VT.getVectorNumElements() *
117            getNumRegisters(Context, VT.getVectorElementType());
118   }
119   return MipsTargetLowering::getNumRegisters(Context, VT);
120 }
121 
getVectorTypeBreakdownForCallingConv(LLVMContext & Context,CallingConv::ID CC,EVT VT,EVT & IntermediateVT,unsigned & NumIntermediates,MVT & RegisterVT) const122 unsigned MipsTargetLowering::getVectorTypeBreakdownForCallingConv(
123     LLVMContext &Context, CallingConv::ID CC, EVT VT, EVT &IntermediateVT,
124     unsigned &NumIntermediates, MVT &RegisterVT) const {
125   if (VT.isPow2VectorType() && VT.getVectorElementType().isRound()) {
126     IntermediateVT = getRegisterTypeForCallingConv(Context, CC, VT);
127     RegisterVT = IntermediateVT.getSimpleVT();
128     NumIntermediates = getNumRegistersForCallingConv(Context, CC, VT);
129     return NumIntermediates;
130   }
131   IntermediateVT = VT.getVectorElementType();
132   NumIntermediates = VT.getVectorNumElements();
133   RegisterVT = getRegisterType(Context, IntermediateVT);
134   return NumIntermediates * getNumRegisters(Context, IntermediateVT);
135 }
136 
getGlobalReg(SelectionDAG & DAG,EVT Ty) const137 SDValue MipsTargetLowering::getGlobalReg(SelectionDAG &DAG, EVT Ty) const {
138   MachineFunction &MF = DAG.getMachineFunction();
139   MipsFunctionInfo *FI = MF.getInfo<MipsFunctionInfo>();
140   return DAG.getRegister(FI->getGlobalBaseReg(MF), Ty);
141 }
142 
getTargetNode(GlobalAddressSDNode * N,EVT Ty,SelectionDAG & DAG,unsigned Flag) const143 SDValue MipsTargetLowering::getTargetNode(GlobalAddressSDNode *N, EVT Ty,
144                                           SelectionDAG &DAG,
145                                           unsigned Flag) const {
146   return DAG.getTargetGlobalAddress(N->getGlobal(), SDLoc(N), Ty, 0, Flag);
147 }
148 
getTargetNode(ExternalSymbolSDNode * N,EVT Ty,SelectionDAG & DAG,unsigned Flag) const149 SDValue MipsTargetLowering::getTargetNode(ExternalSymbolSDNode *N, EVT Ty,
150                                           SelectionDAG &DAG,
151                                           unsigned Flag) const {
152   return DAG.getTargetExternalSymbol(N->getSymbol(), Ty, Flag);
153 }
154 
getTargetNode(BlockAddressSDNode * N,EVT Ty,SelectionDAG & DAG,unsigned Flag) const155 SDValue MipsTargetLowering::getTargetNode(BlockAddressSDNode *N, EVT Ty,
156                                           SelectionDAG &DAG,
157                                           unsigned Flag) const {
158   return DAG.getTargetBlockAddress(N->getBlockAddress(), Ty, 0, Flag);
159 }
160 
getTargetNode(JumpTableSDNode * N,EVT Ty,SelectionDAG & DAG,unsigned Flag) const161 SDValue MipsTargetLowering::getTargetNode(JumpTableSDNode *N, EVT Ty,
162                                           SelectionDAG &DAG,
163                                           unsigned Flag) const {
164   return DAG.getTargetJumpTable(N->getIndex(), Ty, Flag);
165 }
166 
getTargetNode(ConstantPoolSDNode * N,EVT Ty,SelectionDAG & DAG,unsigned Flag) const167 SDValue MipsTargetLowering::getTargetNode(ConstantPoolSDNode *N, EVT Ty,
168                                           SelectionDAG &DAG,
169                                           unsigned Flag) const {
170   return DAG.getTargetConstantPool(N->getConstVal(), Ty, N->getAlign(),
171                                    N->getOffset(), Flag);
172 }
173 
getTargetNodeName(unsigned Opcode) const174 const char *MipsTargetLowering::getTargetNodeName(unsigned Opcode) const {
175   switch ((MipsISD::NodeType)Opcode) {
176   case MipsISD::FIRST_NUMBER:      break;
177   case MipsISD::JmpLink:           return "MipsISD::JmpLink";
178   case MipsISD::TailCall:          return "MipsISD::TailCall";
179   case MipsISD::Highest:           return "MipsISD::Highest";
180   case MipsISD::Higher:            return "MipsISD::Higher";
181   case MipsISD::Hi:                return "MipsISD::Hi";
182   case MipsISD::Lo:                return "MipsISD::Lo";
183   case MipsISD::GotHi:             return "MipsISD::GotHi";
184   case MipsISD::TlsHi:             return "MipsISD::TlsHi";
185   case MipsISD::GPRel:             return "MipsISD::GPRel";
186   case MipsISD::ThreadPointer:     return "MipsISD::ThreadPointer";
187   case MipsISD::Ret:               return "MipsISD::Ret";
188   case MipsISD::ERet:              return "MipsISD::ERet";
189   case MipsISD::EH_RETURN:         return "MipsISD::EH_RETURN";
190   case MipsISD::FAbs:              return "MipsISD::FAbs";
191   case MipsISD::FMS:               return "MipsISD::FMS";
192   case MipsISD::FPBrcond:          return "MipsISD::FPBrcond";
193   case MipsISD::FPCmp:             return "MipsISD::FPCmp";
194   case MipsISD::FSELECT:           return "MipsISD::FSELECT";
195   case MipsISD::MTC1_D64:          return "MipsISD::MTC1_D64";
196   case MipsISD::CMovFP_T:          return "MipsISD::CMovFP_T";
197   case MipsISD::CMovFP_F:          return "MipsISD::CMovFP_F";
198   case MipsISD::TruncIntFP:        return "MipsISD::TruncIntFP";
199   case MipsISD::MFHI:              return "MipsISD::MFHI";
200   case MipsISD::MFLO:              return "MipsISD::MFLO";
201   case MipsISD::MTLOHI:            return "MipsISD::MTLOHI";
202   case MipsISD::Mult:              return "MipsISD::Mult";
203   case MipsISD::Multu:             return "MipsISD::Multu";
204   case MipsISD::MAdd:              return "MipsISD::MAdd";
205   case MipsISD::MAddu:             return "MipsISD::MAddu";
206   case MipsISD::MSub:              return "MipsISD::MSub";
207   case MipsISD::MSubu:             return "MipsISD::MSubu";
208   case MipsISD::DivRem:            return "MipsISD::DivRem";
209   case MipsISD::DivRemU:           return "MipsISD::DivRemU";
210   case MipsISD::DivRem16:          return "MipsISD::DivRem16";
211   case MipsISD::DivRemU16:         return "MipsISD::DivRemU16";
212   case MipsISD::BuildPairF64:      return "MipsISD::BuildPairF64";
213   case MipsISD::ExtractElementF64: return "MipsISD::ExtractElementF64";
214   case MipsISD::Wrapper:           return "MipsISD::Wrapper";
215   case MipsISD::DynAlloc:          return "MipsISD::DynAlloc";
216   case MipsISD::Sync:              return "MipsISD::Sync";
217   case MipsISD::Ext:               return "MipsISD::Ext";
218   case MipsISD::Ins:               return "MipsISD::Ins";
219   case MipsISD::CIns:              return "MipsISD::CIns";
220   case MipsISD::LWL:               return "MipsISD::LWL";
221   case MipsISD::LWR:               return "MipsISD::LWR";
222   case MipsISD::SWL:               return "MipsISD::SWL";
223   case MipsISD::SWR:               return "MipsISD::SWR";
224   case MipsISD::LDL:               return "MipsISD::LDL";
225   case MipsISD::LDR:               return "MipsISD::LDR";
226   case MipsISD::SDL:               return "MipsISD::SDL";
227   case MipsISD::SDR:               return "MipsISD::SDR";
228   case MipsISD::EXTP:              return "MipsISD::EXTP";
229   case MipsISD::EXTPDP:            return "MipsISD::EXTPDP";
230   case MipsISD::EXTR_S_H:          return "MipsISD::EXTR_S_H";
231   case MipsISD::EXTR_W:            return "MipsISD::EXTR_W";
232   case MipsISD::EXTR_R_W:          return "MipsISD::EXTR_R_W";
233   case MipsISD::EXTR_RS_W:         return "MipsISD::EXTR_RS_W";
234   case MipsISD::SHILO:             return "MipsISD::SHILO";
235   case MipsISD::MTHLIP:            return "MipsISD::MTHLIP";
236   case MipsISD::MULSAQ_S_W_PH:     return "MipsISD::MULSAQ_S_W_PH";
237   case MipsISD::MAQ_S_W_PHL:       return "MipsISD::MAQ_S_W_PHL";
238   case MipsISD::MAQ_S_W_PHR:       return "MipsISD::MAQ_S_W_PHR";
239   case MipsISD::MAQ_SA_W_PHL:      return "MipsISD::MAQ_SA_W_PHL";
240   case MipsISD::MAQ_SA_W_PHR:      return "MipsISD::MAQ_SA_W_PHR";
241   case MipsISD::DOUBLE_SELECT_I:   return "MipsISD::DOUBLE_SELECT_I";
242   case MipsISD::DOUBLE_SELECT_I64: return "MipsISD::DOUBLE_SELECT_I64";
243   case MipsISD::DPAU_H_QBL:        return "MipsISD::DPAU_H_QBL";
244   case MipsISD::DPAU_H_QBR:        return "MipsISD::DPAU_H_QBR";
245   case MipsISD::DPSU_H_QBL:        return "MipsISD::DPSU_H_QBL";
246   case MipsISD::DPSU_H_QBR:        return "MipsISD::DPSU_H_QBR";
247   case MipsISD::DPAQ_S_W_PH:       return "MipsISD::DPAQ_S_W_PH";
248   case MipsISD::DPSQ_S_W_PH:       return "MipsISD::DPSQ_S_W_PH";
249   case MipsISD::DPAQ_SA_L_W:       return "MipsISD::DPAQ_SA_L_W";
250   case MipsISD::DPSQ_SA_L_W:       return "MipsISD::DPSQ_SA_L_W";
251   case MipsISD::DPA_W_PH:          return "MipsISD::DPA_W_PH";
252   case MipsISD::DPS_W_PH:          return "MipsISD::DPS_W_PH";
253   case MipsISD::DPAQX_S_W_PH:      return "MipsISD::DPAQX_S_W_PH";
254   case MipsISD::DPAQX_SA_W_PH:     return "MipsISD::DPAQX_SA_W_PH";
255   case MipsISD::DPAX_W_PH:         return "MipsISD::DPAX_W_PH";
256   case MipsISD::DPSX_W_PH:         return "MipsISD::DPSX_W_PH";
257   case MipsISD::DPSQX_S_W_PH:      return "MipsISD::DPSQX_S_W_PH";
258   case MipsISD::DPSQX_SA_W_PH:     return "MipsISD::DPSQX_SA_W_PH";
259   case MipsISD::MULSA_W_PH:        return "MipsISD::MULSA_W_PH";
260   case MipsISD::MULT:              return "MipsISD::MULT";
261   case MipsISD::MULTU:             return "MipsISD::MULTU";
262   case MipsISD::MADD_DSP:          return "MipsISD::MADD_DSP";
263   case MipsISD::MADDU_DSP:         return "MipsISD::MADDU_DSP";
264   case MipsISD::MSUB_DSP:          return "MipsISD::MSUB_DSP";
265   case MipsISD::MSUBU_DSP:         return "MipsISD::MSUBU_DSP";
266   case MipsISD::SHLL_DSP:          return "MipsISD::SHLL_DSP";
267   case MipsISD::SHRA_DSP:          return "MipsISD::SHRA_DSP";
268   case MipsISD::SHRL_DSP:          return "MipsISD::SHRL_DSP";
269   case MipsISD::SETCC_DSP:         return "MipsISD::SETCC_DSP";
270   case MipsISD::SELECT_CC_DSP:     return "MipsISD::SELECT_CC_DSP";
271   case MipsISD::VALL_ZERO:         return "MipsISD::VALL_ZERO";
272   case MipsISD::VANY_ZERO:         return "MipsISD::VANY_ZERO";
273   case MipsISD::VALL_NONZERO:      return "MipsISD::VALL_NONZERO";
274   case MipsISD::VANY_NONZERO:      return "MipsISD::VANY_NONZERO";
275   case MipsISD::VCEQ:              return "MipsISD::VCEQ";
276   case MipsISD::VCLE_S:            return "MipsISD::VCLE_S";
277   case MipsISD::VCLE_U:            return "MipsISD::VCLE_U";
278   case MipsISD::VCLT_S:            return "MipsISD::VCLT_S";
279   case MipsISD::VCLT_U:            return "MipsISD::VCLT_U";
280   case MipsISD::VEXTRACT_SEXT_ELT: return "MipsISD::VEXTRACT_SEXT_ELT";
281   case MipsISD::VEXTRACT_ZEXT_ELT: return "MipsISD::VEXTRACT_ZEXT_ELT";
282   case MipsISD::VNOR:              return "MipsISD::VNOR";
283   case MipsISD::VSHF:              return "MipsISD::VSHF";
284   case MipsISD::SHF:               return "MipsISD::SHF";
285   case MipsISD::ILVEV:             return "MipsISD::ILVEV";
286   case MipsISD::ILVOD:             return "MipsISD::ILVOD";
287   case MipsISD::ILVL:              return "MipsISD::ILVL";
288   case MipsISD::ILVR:              return "MipsISD::ILVR";
289   case MipsISD::PCKEV:             return "MipsISD::PCKEV";
290   case MipsISD::PCKOD:             return "MipsISD::PCKOD";
291   case MipsISD::INSVE:             return "MipsISD::INSVE";
292   }
293   return nullptr;
294 }
295 
MipsTargetLowering(const MipsTargetMachine & TM,const MipsSubtarget & STI)296 MipsTargetLowering::MipsTargetLowering(const MipsTargetMachine &TM,
297                                        const MipsSubtarget &STI)
298     : TargetLowering(TM), Subtarget(STI), ABI(TM.getABI()) {
299   // Mips does not have i1 type, so use i32 for
300   // setcc operations results (slt, sgt, ...).
301   setBooleanContents(ZeroOrOneBooleanContent);
302   setBooleanVectorContents(ZeroOrNegativeOneBooleanContent);
303   // The cmp.cond.fmt instruction in MIPS32r6/MIPS64r6 uses 0 and -1 like MSA
304   // does. Integer booleans still use 0 and 1.
305   if (Subtarget.hasMips32r6())
306     setBooleanContents(ZeroOrOneBooleanContent,
307                        ZeroOrNegativeOneBooleanContent);
308 
309   // Load extented operations for i1 types must be promoted
310   for (MVT VT : MVT::integer_valuetypes()) {
311     setLoadExtAction(ISD::EXTLOAD,  VT, MVT::i1,  Promote);
312     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i1,  Promote);
313     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i1,  Promote);
314   }
315 
316   // MIPS doesn't have extending float->double load/store.  Set LoadExtAction
317   // for f32, f16
318   for (MVT VT : MVT::fp_valuetypes()) {
319     setLoadExtAction(ISD::EXTLOAD, VT, MVT::f32, Expand);
320     setLoadExtAction(ISD::EXTLOAD, VT, MVT::f16, Expand);
321   }
322 
323   // Set LoadExtAction for f16 vectors to Expand
324   for (MVT VT : MVT::fp_fixedlen_vector_valuetypes()) {
325     MVT F16VT = MVT::getVectorVT(MVT::f16, VT.getVectorNumElements());
326     if (F16VT.isValid())
327       setLoadExtAction(ISD::EXTLOAD, VT, F16VT, Expand);
328   }
329 
330   setTruncStoreAction(MVT::f32, MVT::f16, Expand);
331   setTruncStoreAction(MVT::f64, MVT::f16, Expand);
332 
333   setTruncStoreAction(MVT::f64, MVT::f32, Expand);
334 
335   // Used by legalize types to correctly generate the setcc result.
336   // Without this, every float setcc comes with a AND/OR with the result,
337   // we don't want this, since the fpcmp result goes to a flag register,
338   // which is used implicitly by brcond and select operations.
339   AddPromotedToType(ISD::SETCC, MVT::i1, MVT::i32);
340 
341   // Mips Custom Operations
342   setOperationAction(ISD::BR_JT,              MVT::Other, Expand);
343   setOperationAction(ISD::GlobalAddress,      MVT::i32,   Custom);
344   setOperationAction(ISD::BlockAddress,       MVT::i32,   Custom);
345   setOperationAction(ISD::GlobalTLSAddress,   MVT::i32,   Custom);
346   setOperationAction(ISD::JumpTable,          MVT::i32,   Custom);
347   setOperationAction(ISD::ConstantPool,       MVT::i32,   Custom);
348   setOperationAction(ISD::SELECT,             MVT::f32,   Custom);
349   setOperationAction(ISD::SELECT,             MVT::f64,   Custom);
350   setOperationAction(ISD::SELECT,             MVT::i32,   Custom);
351   setOperationAction(ISD::SETCC,              MVT::f32,   Custom);
352   setOperationAction(ISD::SETCC,              MVT::f64,   Custom);
353   setOperationAction(ISD::BRCOND,             MVT::Other, Custom);
354   setOperationAction(ISD::FABS,               MVT::f32,   Custom);
355   setOperationAction(ISD::FABS,               MVT::f64,   Custom);
356   setOperationAction(ISD::FCOPYSIGN,          MVT::f32,   Custom);
357   setOperationAction(ISD::FCOPYSIGN,          MVT::f64,   Custom);
358   setOperationAction(ISD::FP_TO_SINT,         MVT::i32,   Custom);
359 
360   if (Subtarget.hasMips32r2() ||
361       getTargetMachine().getTargetTriple().isOSLinux())
362     setOperationAction(ISD::READCYCLECOUNTER, MVT::i64, Custom);
363 
364   // Lower fmin/fmax/fclass operations for MIPS R6.
365   if (Subtarget.hasMips32r6()) {
366     setOperationAction(ISD::FMINNUM_IEEE, MVT::f32, Legal);
367     setOperationAction(ISD::FMAXNUM_IEEE, MVT::f32, Legal);
368     setOperationAction(ISD::FMINNUM, MVT::f32, Legal);
369     setOperationAction(ISD::FMAXNUM, MVT::f32, Legal);
370     setOperationAction(ISD::FMINNUM_IEEE, MVT::f64, Legal);
371     setOperationAction(ISD::FMAXNUM_IEEE, MVT::f64, Legal);
372     setOperationAction(ISD::FMINNUM, MVT::f64, Legal);
373     setOperationAction(ISD::FMAXNUM, MVT::f64, Legal);
374     setOperationAction(ISD::IS_FPCLASS, MVT::f32, Legal);
375     setOperationAction(ISD::IS_FPCLASS, MVT::f64, Legal);
376     setOperationAction(ISD::FCANONICALIZE, MVT::f32, Legal);
377     setOperationAction(ISD::FCANONICALIZE, MVT::f64, Legal);
378   } else {
379     setOperationAction(ISD::FCANONICALIZE, MVT::f32, Custom);
380     setOperationAction(ISD::FCANONICALIZE, MVT::f64, Custom);
381   }
382 
383   if (Subtarget.isGP64bit()) {
384     setOperationAction(ISD::GlobalAddress,      MVT::i64,   Custom);
385     setOperationAction(ISD::BlockAddress,       MVT::i64,   Custom);
386     setOperationAction(ISD::GlobalTLSAddress,   MVT::i64,   Custom);
387     setOperationAction(ISD::JumpTable,          MVT::i64,   Custom);
388     setOperationAction(ISD::ConstantPool,       MVT::i64,   Custom);
389     setOperationAction(ISD::SELECT,             MVT::i64,   Custom);
390     if (Subtarget.hasMips64r6()) {
391       setOperationAction(ISD::LOAD,               MVT::i64,   Legal);
392       setOperationAction(ISD::STORE,              MVT::i64,   Legal);
393     } else {
394       setOperationAction(ISD::LOAD,               MVT::i64,   Custom);
395       setOperationAction(ISD::STORE,              MVT::i64,   Custom);
396     }
397     setOperationAction(ISD::FP_TO_SINT,         MVT::i64,   Custom);
398     setOperationAction(ISD::SHL_PARTS,          MVT::i64,   Custom);
399     setOperationAction(ISD::SRA_PARTS,          MVT::i64,   Custom);
400     setOperationAction(ISD::SRL_PARTS,          MVT::i64,   Custom);
401   }
402 
403   if (!Subtarget.isGP64bit()) {
404     setOperationAction(ISD::SHL_PARTS,          MVT::i32,   Custom);
405     setOperationAction(ISD::SRA_PARTS,          MVT::i32,   Custom);
406     setOperationAction(ISD::SRL_PARTS,          MVT::i32,   Custom);
407   }
408 
409   setOperationAction(ISD::EH_DWARF_CFA,         MVT::i32,   Custom);
410   if (Subtarget.isGP64bit())
411     setOperationAction(ISD::EH_DWARF_CFA,       MVT::i64,   Custom);
412 
413   setOperationAction(ISD::SDIV, MVT::i32, Expand);
414   setOperationAction(ISD::SREM, MVT::i32, Expand);
415   setOperationAction(ISD::UDIV, MVT::i32, Expand);
416   setOperationAction(ISD::UREM, MVT::i32, Expand);
417   setOperationAction(ISD::SDIV, MVT::i64, Expand);
418   setOperationAction(ISD::SREM, MVT::i64, Expand);
419   setOperationAction(ISD::UDIV, MVT::i64, Expand);
420   setOperationAction(ISD::UREM, MVT::i64, Expand);
421 
422   // Operations not directly supported by Mips.
423   setOperationAction(ISD::BR_CC,             MVT::f32,   Expand);
424   setOperationAction(ISD::BR_CC,             MVT::f64,   Expand);
425   setOperationAction(ISD::BR_CC,             MVT::i32,   Expand);
426   setOperationAction(ISD::BR_CC,             MVT::i64,   Expand);
427   setOperationAction(ISD::SELECT_CC,         MVT::i32,   Expand);
428   setOperationAction(ISD::SELECT_CC,         MVT::i64,   Expand);
429   setOperationAction(ISD::SELECT_CC,         MVT::f32,   Expand);
430   setOperationAction(ISD::SELECT_CC,         MVT::f64,   Expand);
431   setOperationAction(ISD::UINT_TO_FP,        MVT::i32,   Expand);
432   setOperationAction(ISD::UINT_TO_FP,        MVT::i64,   Expand);
433   setOperationAction(ISD::FP_TO_UINT,        MVT::i32,   Expand);
434   setOperationAction(ISD::FP_TO_UINT,        MVT::i64,   Expand);
435   setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i1,    Expand);
436   if (Subtarget.hasCnMips()) {
437     setOperationAction(ISD::CTPOP,           MVT::i32,   Legal);
438     setOperationAction(ISD::CTPOP,           MVT::i64,   Legal);
439   } else {
440     setOperationAction(ISD::CTPOP,           MVT::i32,   Expand);
441     setOperationAction(ISD::CTPOP,           MVT::i64,   Expand);
442   }
443   setOperationAction(ISD::CTTZ,              MVT::i32,   Expand);
444   setOperationAction(ISD::CTTZ,              MVT::i64,   Expand);
445   setOperationAction(ISD::ROTL,              MVT::i32,   Expand);
446   setOperationAction(ISD::ROTL,              MVT::i64,   Expand);
447   setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32,  Expand);
448   setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i64,  Expand);
449 
450   if (!Subtarget.hasMips32r2())
451     setOperationAction(ISD::ROTR, MVT::i32,   Expand);
452 
453   if (!Subtarget.hasMips64r2())
454     setOperationAction(ISD::ROTR, MVT::i64,   Expand);
455 
456   setOperationAction(ISD::FSIN,              MVT::f32,   Expand);
457   setOperationAction(ISD::FSIN,              MVT::f64,   Expand);
458   setOperationAction(ISD::FCOS,              MVT::f32,   Expand);
459   setOperationAction(ISD::FCOS,              MVT::f64,   Expand);
460   setOperationAction(ISD::FSINCOS,           MVT::f32,   Expand);
461   setOperationAction(ISD::FSINCOS,           MVT::f64,   Expand);
462   setOperationAction(ISD::FPOW,              MVT::f32,   Expand);
463   setOperationAction(ISD::FPOW,              MVT::f64,   Expand);
464   setOperationAction(ISD::FLOG,              MVT::f32,   Expand);
465   setOperationAction(ISD::FLOG2,             MVT::f32,   Expand);
466   setOperationAction(ISD::FLOG10,            MVT::f32,   Expand);
467   setOperationAction(ISD::FEXP,              MVT::f32,   Expand);
468   setOperationAction(ISD::FMA,               MVT::f32,   Expand);
469   setOperationAction(ISD::FMA,               MVT::f64,   Expand);
470   setOperationAction(ISD::FREM,              MVT::f32,   Expand);
471   setOperationAction(ISD::FREM,              MVT::f64,   Expand);
472 
473   // Lower f16 conversion operations into library calls
474   setOperationAction(ISD::FP16_TO_FP,        MVT::f32,   Expand);
475   setOperationAction(ISD::FP_TO_FP16,        MVT::f32,   Expand);
476   setOperationAction(ISD::FP16_TO_FP,        MVT::f64,   Expand);
477   setOperationAction(ISD::FP_TO_FP16,        MVT::f64,   Expand);
478 
479   setOperationAction(ISD::EH_RETURN, MVT::Other, Custom);
480 
481   setOperationAction(ISD::VASTART,           MVT::Other, Custom);
482   setOperationAction(ISD::VAARG,             MVT::Other, Custom);
483   setOperationAction(ISD::VACOPY,            MVT::Other, Expand);
484   setOperationAction(ISD::VAEND,             MVT::Other, Expand);
485 
486   // Use the default for now
487   setOperationAction(ISD::STACKSAVE,         MVT::Other, Expand);
488   setOperationAction(ISD::STACKRESTORE,      MVT::Other, Expand);
489 
490   if (!Subtarget.isGP64bit()) {
491     setOperationAction(ISD::ATOMIC_LOAD,     MVT::i64,   Expand);
492     setOperationAction(ISD::ATOMIC_STORE,    MVT::i64,   Expand);
493   }
494 
495   if (!Subtarget.hasMips32r2()) {
496     setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i8,  Expand);
497     setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i16, Expand);
498   }
499 
500   // MIPS16 lacks MIPS32's clz and clo instructions.
501   if (!Subtarget.hasMips32() || Subtarget.inMips16Mode())
502     setOperationAction(ISD::CTLZ, MVT::i32, Expand);
503   if (!Subtarget.hasMips64())
504     setOperationAction(ISD::CTLZ, MVT::i64, Expand);
505 
506   if (!Subtarget.hasMips32r2())
507     setOperationAction(ISD::BSWAP, MVT::i32, Expand);
508   if (!Subtarget.hasMips64r2())
509     setOperationAction(ISD::BSWAP, MVT::i64, Expand);
510 
511   if (Subtarget.isGP64bit() && Subtarget.hasMips64r6()) {
512     setLoadExtAction(ISD::SEXTLOAD, MVT::i64, MVT::i32, Legal);
513     setLoadExtAction(ISD::ZEXTLOAD, MVT::i64, MVT::i32, Legal);
514     setLoadExtAction(ISD::EXTLOAD, MVT::i64, MVT::i32, Legal);
515     setTruncStoreAction(MVT::i64, MVT::i32, Legal);
516   } else if (Subtarget.isGP64bit()) {
517     setLoadExtAction(ISD::SEXTLOAD, MVT::i64, MVT::i32, Custom);
518     setLoadExtAction(ISD::ZEXTLOAD, MVT::i64, MVT::i32, Custom);
519     setLoadExtAction(ISD::EXTLOAD, MVT::i64, MVT::i32, Custom);
520     setTruncStoreAction(MVT::i64, MVT::i32, Custom);
521   }
522 
523   setOperationAction(ISD::TRAP, MVT::Other, Legal);
524 
525   setTargetDAGCombine({ISD::SDIVREM, ISD::UDIVREM, ISD::SELECT, ISD::AND,
526                        ISD::OR, ISD::ADD, ISD::SUB, ISD::AssertZext, ISD::SHL,
527                        ISD::SIGN_EXTEND});
528 
529   if (Subtarget.isGP64bit())
530     setMaxAtomicSizeInBitsSupported(64);
531   else
532     setMaxAtomicSizeInBitsSupported(32);
533 
534   setMinFunctionAlignment(Subtarget.isGP64bit() ? Align(8) : Align(4));
535 
536   // The arguments on the stack are defined in terms of 4-byte slots on O32
537   // and 8-byte slots on N32/N64.
538   setMinStackArgumentAlignment((ABI.IsN32() || ABI.IsN64()) ? Align(8)
539                                                             : Align(4));
540 
541   setStackPointerRegisterToSaveRestore(ABI.IsN64() ? Mips::SP_64 : Mips::SP);
542 
543   MaxStoresPerMemcpy = 16;
544 
545   isMicroMips = Subtarget.inMicroMipsMode();
546 }
547 
548 const MipsTargetLowering *
create(const MipsTargetMachine & TM,const MipsSubtarget & STI)549 MipsTargetLowering::create(const MipsTargetMachine &TM,
550                            const MipsSubtarget &STI) {
551   if (STI.inMips16Mode())
552     return createMips16TargetLowering(TM, STI);
553 
554   return createMipsSETargetLowering(TM, STI);
555 }
556 
557 // Create a fast isel object.
558 FastISel *
createFastISel(FunctionLoweringInfo & funcInfo,const TargetLibraryInfo * libInfo) const559 MipsTargetLowering::createFastISel(FunctionLoweringInfo &funcInfo,
560                                   const TargetLibraryInfo *libInfo) const {
561   const MipsTargetMachine &TM =
562       static_cast<const MipsTargetMachine &>(funcInfo.MF->getTarget());
563 
564   // We support only the standard encoding [MIPS32,MIPS32R5] ISAs.
565   bool UseFastISel = TM.Options.EnableFastISel && Subtarget.hasMips32() &&
566                      !Subtarget.hasMips32r6() && !Subtarget.inMips16Mode() &&
567                      !Subtarget.inMicroMipsMode();
568 
569   // Disable if either of the following is true:
570   // We do not generate PIC, the ABI is not O32, XGOT is being used.
571   if (!TM.isPositionIndependent() || !TM.getABI().IsO32() ||
572       Subtarget.useXGOT())
573     UseFastISel = false;
574 
575   return UseFastISel ? Mips::createFastISel(funcInfo, libInfo) : nullptr;
576 }
577 
getSetCCResultType(const DataLayout &,LLVMContext &,EVT VT) const578 EVT MipsTargetLowering::getSetCCResultType(const DataLayout &, LLVMContext &,
579                                            EVT VT) const {
580   if (!VT.isVector())
581     return MVT::i32;
582   return VT.changeVectorElementTypeToInteger();
583 }
584 
performDivRemCombine(SDNode * N,SelectionDAG & DAG,TargetLowering::DAGCombinerInfo & DCI,const MipsSubtarget & Subtarget)585 static SDValue performDivRemCombine(SDNode *N, SelectionDAG &DAG,
586                                     TargetLowering::DAGCombinerInfo &DCI,
587                                     const MipsSubtarget &Subtarget) {
588   if (DCI.isBeforeLegalizeOps())
589     return SDValue();
590 
591   EVT Ty = N->getValueType(0);
592   unsigned LO = (Ty == MVT::i32) ? Mips::LO0 : Mips::LO0_64;
593   unsigned HI = (Ty == MVT::i32) ? Mips::HI0 : Mips::HI0_64;
594   unsigned Opc = N->getOpcode() == ISD::SDIVREM ? MipsISD::DivRem16 :
595                                                   MipsISD::DivRemU16;
596   SDLoc DL(N);
597 
598   SDValue DivRem = DAG.getNode(Opc, DL, MVT::Glue,
599                                N->getOperand(0), N->getOperand(1));
600   SDValue InChain = DAG.getEntryNode();
601   SDValue InGlue = DivRem;
602 
603   // insert MFLO
604   if (N->hasAnyUseOfValue(0)) {
605     SDValue CopyFromLo = DAG.getCopyFromReg(InChain, DL, LO, Ty,
606                                             InGlue);
607     DAG.ReplaceAllUsesOfValueWith(SDValue(N, 0), CopyFromLo);
608     InChain = CopyFromLo.getValue(1);
609     InGlue = CopyFromLo.getValue(2);
610   }
611 
612   // insert MFHI
613   if (N->hasAnyUseOfValue(1)) {
614     SDValue CopyFromHi = DAG.getCopyFromReg(InChain, DL,
615                                             HI, Ty, InGlue);
616     DAG.ReplaceAllUsesOfValueWith(SDValue(N, 1), CopyFromHi);
617   }
618 
619   return SDValue();
620 }
621 
condCodeToFCC(ISD::CondCode CC)622 static Mips::CondCode condCodeToFCC(ISD::CondCode CC) {
623   switch (CC) {
624   default: llvm_unreachable("Unknown fp condition code!");
625   case ISD::SETEQ:
626   case ISD::SETOEQ: return Mips::FCOND_OEQ;
627   case ISD::SETUNE: return Mips::FCOND_UNE;
628   case ISD::SETLT:
629   case ISD::SETOLT: return Mips::FCOND_OLT;
630   case ISD::SETGT:
631   case ISD::SETOGT: return Mips::FCOND_OGT;
632   case ISD::SETLE:
633   case ISD::SETOLE: return Mips::FCOND_OLE;
634   case ISD::SETGE:
635   case ISD::SETOGE: return Mips::FCOND_OGE;
636   case ISD::SETULT: return Mips::FCOND_ULT;
637   case ISD::SETULE: return Mips::FCOND_ULE;
638   case ISD::SETUGT: return Mips::FCOND_UGT;
639   case ISD::SETUGE: return Mips::FCOND_UGE;
640   case ISD::SETUO:  return Mips::FCOND_UN;
641   case ISD::SETO:   return Mips::FCOND_OR;
642   case ISD::SETNE:
643   case ISD::SETONE: return Mips::FCOND_ONE;
644   case ISD::SETUEQ: return Mips::FCOND_UEQ;
645   }
646 }
647 
648 /// This function returns true if the floating point conditional branches and
649 /// conditional moves which use condition code CC should be inverted.
invertFPCondCodeUser(Mips::CondCode CC)650 static bool invertFPCondCodeUser(Mips::CondCode CC) {
651   if (CC >= Mips::FCOND_F && CC <= Mips::FCOND_NGT)
652     return false;
653 
654   assert((CC >= Mips::FCOND_T && CC <= Mips::FCOND_GT) &&
655          "Illegal Condition Code");
656 
657   return true;
658 }
659 
660 // Creates and returns an FPCmp node from a setcc node.
661 // Returns Op if setcc is not a floating point comparison.
createFPCmp(SelectionDAG & DAG,const SDValue & Op)662 static SDValue createFPCmp(SelectionDAG &DAG, const SDValue &Op) {
663   // must be a SETCC node
664   if (Op.getOpcode() != ISD::SETCC)
665     return Op;
666 
667   SDValue LHS = Op.getOperand(0);
668 
669   if (!LHS.getValueType().isFloatingPoint())
670     return Op;
671 
672   SDValue RHS = Op.getOperand(1);
673   SDLoc DL(Op);
674 
675   // Assume the 3rd operand is a CondCodeSDNode. Add code to check the type of
676   // node if necessary.
677   ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(2))->get();
678 
679   return DAG.getNode(MipsISD::FPCmp, DL, MVT::Glue, LHS, RHS,
680                      DAG.getConstant(condCodeToFCC(CC), DL, MVT::i32));
681 }
682 
683 // Creates and returns a CMovFPT/F node.
createCMovFP(SelectionDAG & DAG,SDValue Cond,SDValue True,SDValue False,const SDLoc & DL)684 static SDValue createCMovFP(SelectionDAG &DAG, SDValue Cond, SDValue True,
685                             SDValue False, const SDLoc &DL) {
686   ConstantSDNode *CC = cast<ConstantSDNode>(Cond.getOperand(2));
687   bool invert = invertFPCondCodeUser((Mips::CondCode)CC->getSExtValue());
688   SDValue FCC0 = DAG.getRegister(Mips::FCC0, MVT::i32);
689 
690   return DAG.getNode((invert ? MipsISD::CMovFP_F : MipsISD::CMovFP_T), DL,
691                      True.getValueType(), True, FCC0, False, Cond);
692 }
693 
performSELECTCombine(SDNode * N,SelectionDAG & DAG,TargetLowering::DAGCombinerInfo & DCI,const MipsSubtarget & Subtarget)694 static SDValue performSELECTCombine(SDNode *N, SelectionDAG &DAG,
695                                     TargetLowering::DAGCombinerInfo &DCI,
696                                     const MipsSubtarget &Subtarget) {
697   if (DCI.isBeforeLegalizeOps())
698     return SDValue();
699 
700   SDValue SetCC = N->getOperand(0);
701 
702   if ((SetCC.getOpcode() != ISD::SETCC) ||
703       !SetCC.getOperand(0).getValueType().isInteger())
704     return SDValue();
705 
706   SDValue False = N->getOperand(2);
707   EVT FalseTy = False.getValueType();
708 
709   if (!FalseTy.isInteger())
710     return SDValue();
711 
712   ConstantSDNode *FalseC = dyn_cast<ConstantSDNode>(False);
713 
714   // If the RHS (False) is 0, we swap the order of the operands
715   // of ISD::SELECT (obviously also inverting the condition) so that we can
716   // take advantage of conditional moves using the $0 register.
717   // Example:
718   //   return (a != 0) ? x : 0;
719   //     load $reg, x
720   //     movz $reg, $0, a
721   if (!FalseC)
722     return SDValue();
723 
724   const SDLoc DL(N);
725 
726   if (!FalseC->getZExtValue()) {
727     ISD::CondCode CC = cast<CondCodeSDNode>(SetCC.getOperand(2))->get();
728     SDValue True = N->getOperand(1);
729 
730     SetCC = DAG.getSetCC(DL, SetCC.getValueType(), SetCC.getOperand(0),
731                          SetCC.getOperand(1),
732                          ISD::getSetCCInverse(CC, SetCC.getValueType()));
733 
734     return DAG.getNode(ISD::SELECT, DL, FalseTy, SetCC, False, True);
735   }
736 
737   // If both operands are integer constants there's a possibility that we
738   // can do some interesting optimizations.
739   SDValue True = N->getOperand(1);
740   ConstantSDNode *TrueC = dyn_cast<ConstantSDNode>(True);
741 
742   if (!TrueC || !True.getValueType().isInteger())
743     return SDValue();
744 
745   // We'll also ignore MVT::i64 operands as this optimizations proves
746   // to be ineffective because of the required sign extensions as the result
747   // of a SETCC operator is always MVT::i32 for non-vector types.
748   if (True.getValueType() == MVT::i64)
749     return SDValue();
750 
751   int64_t Diff = TrueC->getSExtValue() - FalseC->getSExtValue();
752 
753   // 1)  (a < x) ? y : y-1
754   //  slti $reg1, a, x
755   //  addiu $reg2, $reg1, y-1
756   if (Diff == 1)
757     return DAG.getNode(ISD::ADD, DL, SetCC.getValueType(), SetCC, False);
758 
759   // 2)  (a < x) ? y-1 : y
760   //  slti $reg1, a, x
761   //  xor $reg1, $reg1, 1
762   //  addiu $reg2, $reg1, y-1
763   if (Diff == -1) {
764     ISD::CondCode CC = cast<CondCodeSDNode>(SetCC.getOperand(2))->get();
765     SetCC = DAG.getSetCC(DL, SetCC.getValueType(), SetCC.getOperand(0),
766                          SetCC.getOperand(1),
767                          ISD::getSetCCInverse(CC, SetCC.getValueType()));
768     return DAG.getNode(ISD::ADD, DL, SetCC.getValueType(), SetCC, True);
769   }
770 
771   // Could not optimize.
772   return SDValue();
773 }
774 
performCMovFPCombine(SDNode * N,SelectionDAG & DAG,TargetLowering::DAGCombinerInfo & DCI,const MipsSubtarget & Subtarget)775 static SDValue performCMovFPCombine(SDNode *N, SelectionDAG &DAG,
776                                     TargetLowering::DAGCombinerInfo &DCI,
777                                     const MipsSubtarget &Subtarget) {
778   if (DCI.isBeforeLegalizeOps())
779     return SDValue();
780 
781   SDValue ValueIfTrue = N->getOperand(0), ValueIfFalse = N->getOperand(2);
782 
783   ConstantSDNode *FalseC = dyn_cast<ConstantSDNode>(ValueIfFalse);
784   if (!FalseC || FalseC->getZExtValue())
785     return SDValue();
786 
787   // Since RHS (False) is 0, we swap the order of the True/False operands
788   // (obviously also inverting the condition) so that we can
789   // take advantage of conditional moves using the $0 register.
790   // Example:
791   //   return (a != 0) ? x : 0;
792   //     load $reg, x
793   //     movz $reg, $0, a
794   unsigned Opc = (N->getOpcode() == MipsISD::CMovFP_T) ? MipsISD::CMovFP_F :
795                                                          MipsISD::CMovFP_T;
796 
797   SDValue FCC = N->getOperand(1), Glue = N->getOperand(3);
798   return DAG.getNode(Opc, SDLoc(N), ValueIfFalse.getValueType(),
799                      ValueIfFalse, FCC, ValueIfTrue, Glue);
800 }
801 
performANDCombine(SDNode * N,SelectionDAG & DAG,TargetLowering::DAGCombinerInfo & DCI,const MipsSubtarget & Subtarget)802 static SDValue performANDCombine(SDNode *N, SelectionDAG &DAG,
803                                  TargetLowering::DAGCombinerInfo &DCI,
804                                  const MipsSubtarget &Subtarget) {
805   if (DCI.isBeforeLegalizeOps() || !Subtarget.hasExtractInsert())
806     return SDValue();
807 
808   SDValue FirstOperand = N->getOperand(0);
809   unsigned FirstOperandOpc = FirstOperand.getOpcode();
810   SDValue Mask = N->getOperand(1);
811   EVT ValTy = N->getValueType(0);
812   SDLoc DL(N);
813 
814   uint64_t Pos = 0;
815   unsigned SMPos, SMSize;
816   ConstantSDNode *CN;
817   SDValue NewOperand;
818   unsigned Opc;
819 
820   // Op's second operand must be a shifted mask.
821   if (!(CN = dyn_cast<ConstantSDNode>(Mask)) ||
822       !isShiftedMask_64(CN->getZExtValue(), SMPos, SMSize))
823     return SDValue();
824 
825   if (FirstOperandOpc == ISD::SRA || FirstOperandOpc == ISD::SRL) {
826     // Pattern match EXT.
827     //  $dst = and ((sra or srl) $src , pos), (2**size - 1)
828     //  => ext $dst, $src, pos, size
829 
830     // The second operand of the shift must be an immediate.
831     if (!(CN = dyn_cast<ConstantSDNode>(FirstOperand.getOperand(1))))
832       return SDValue();
833 
834     Pos = CN->getZExtValue();
835 
836     // Return if the shifted mask does not start at bit 0 or the sum of its size
837     // and Pos exceeds the word's size.
838     if (SMPos != 0 || Pos + SMSize > ValTy.getSizeInBits())
839       return SDValue();
840 
841     Opc = MipsISD::Ext;
842     NewOperand = FirstOperand.getOperand(0);
843   } else if (FirstOperandOpc == ISD::SHL && Subtarget.hasCnMips()) {
844     // Pattern match CINS.
845     //  $dst = and (shl $src , pos), mask
846     //  => cins $dst, $src, pos, size
847     // mask is a shifted mask with consecutive 1's, pos = shift amount,
848     // size = population count.
849 
850     // The second operand of the shift must be an immediate.
851     if (!(CN = dyn_cast<ConstantSDNode>(FirstOperand.getOperand(1))))
852       return SDValue();
853 
854     Pos = CN->getZExtValue();
855 
856     if (SMPos != Pos || Pos >= ValTy.getSizeInBits() || SMSize >= 32 ||
857         Pos + SMSize > ValTy.getSizeInBits())
858       return SDValue();
859 
860     NewOperand = FirstOperand.getOperand(0);
861     // SMSize is 'location' (position) in this case, not size.
862     SMSize--;
863     Opc = MipsISD::CIns;
864   } else {
865     // Pattern match EXT.
866     //  $dst = and $src, (2**size - 1) , if size > 16
867     //  => ext $dst, $src, pos, size , pos = 0
868 
869     // If the mask is <= 0xffff, andi can be used instead.
870     if (CN->getZExtValue() <= 0xffff)
871       return SDValue();
872 
873     // Return if the mask doesn't start at position 0.
874     if (SMPos)
875       return SDValue();
876 
877     Opc = MipsISD::Ext;
878     NewOperand = FirstOperand;
879   }
880   return DAG.getNode(Opc, DL, ValTy, NewOperand,
881                      DAG.getConstant(Pos, DL, MVT::i32),
882                      DAG.getConstant(SMSize, DL, MVT::i32));
883 }
884 
performORCombine(SDNode * N,SelectionDAG & DAG,TargetLowering::DAGCombinerInfo & DCI,const MipsSubtarget & Subtarget)885 static SDValue performORCombine(SDNode *N, SelectionDAG &DAG,
886                                 TargetLowering::DAGCombinerInfo &DCI,
887                                 const MipsSubtarget &Subtarget) {
888   if (DCI.isBeforeLegalizeOps() || !Subtarget.hasExtractInsert())
889     return SDValue();
890 
891   SDValue FirstOperand = N->getOperand(0), SecondOperand = N->getOperand(1);
892   unsigned SMPos0, SMSize0, SMPos1, SMSize1;
893   ConstantSDNode *CN, *CN1;
894 
895   if ((FirstOperand.getOpcode() == ISD::AND &&
896        SecondOperand.getOpcode() == ISD::SHL) ||
897       (FirstOperand.getOpcode() == ISD::SHL &&
898        SecondOperand.getOpcode() == ISD::AND)) {
899     // Pattern match INS.
900     //   $dst = or (and $src1, (2**size0 - 1)), (shl $src2, size0)
901     //   ==> ins $src1, $src2, pos, size, pos = size0, size = 32 - pos;
902     //   Or:
903     //   $dst = or (shl $src2, size0), (and $src1, (2**size0 - 1))
904     //   ==> ins $src1, $src2, pos, size, pos = size0, size = 32 - pos;
905     SDValue AndOperand0 = FirstOperand.getOpcode() == ISD::AND
906                               ? FirstOperand.getOperand(0)
907                               : SecondOperand.getOperand(0);
908     SDValue ShlOperand0 = FirstOperand.getOpcode() == ISD::AND
909                               ? SecondOperand.getOperand(0)
910                               : FirstOperand.getOperand(0);
911     SDValue AndMask = FirstOperand.getOpcode() == ISD::AND
912                           ? FirstOperand.getOperand(1)
913                           : SecondOperand.getOperand(1);
914     if (!(CN = dyn_cast<ConstantSDNode>(AndMask)) ||
915         !isShiftedMask_64(CN->getZExtValue(), SMPos0, SMSize0))
916       return SDValue();
917 
918     SDValue ShlShift = FirstOperand.getOpcode() == ISD::AND
919                            ? SecondOperand.getOperand(1)
920                            : FirstOperand.getOperand(1);
921     if (!(CN = dyn_cast<ConstantSDNode>(ShlShift)))
922       return SDValue();
923     uint64_t ShlShiftValue = CN->getZExtValue();
924 
925     if (SMPos0 != 0 || SMSize0 != ShlShiftValue)
926       return SDValue();
927 
928     SDLoc DL(N);
929     EVT ValTy = N->getValueType(0);
930     SMPos1 = ShlShiftValue;
931     assert(SMPos1 < ValTy.getSizeInBits());
932     SMSize1 = (ValTy == MVT::i64 ? 64 : 32) - SMPos1;
933     return DAG.getNode(MipsISD::Ins, DL, ValTy, ShlOperand0,
934                        DAG.getConstant(SMPos1, DL, MVT::i32),
935                        DAG.getConstant(SMSize1, DL, MVT::i32), AndOperand0);
936   }
937 
938   // See if Op's first operand matches (and $src1 , mask0).
939   if (FirstOperand.getOpcode() != ISD::AND)
940     return SDValue();
941 
942   // Pattern match INS.
943   //  $dst = or (and $src1 , mask0), (and (shl $src, pos), mask1),
944   //  where mask1 = (2**size - 1) << pos, mask0 = ~mask1
945   //  => ins $dst, $src, size, pos, $src1
946   if (!(CN = dyn_cast<ConstantSDNode>(FirstOperand.getOperand(1))) ||
947       !isShiftedMask_64(~CN->getSExtValue(), SMPos0, SMSize0))
948     return SDValue();
949 
950   // See if Op's second operand matches (and (shl $src, pos), mask1).
951   if (SecondOperand.getOpcode() == ISD::AND &&
952       SecondOperand.getOperand(0).getOpcode() == ISD::SHL) {
953 
954     if (!(CN = dyn_cast<ConstantSDNode>(SecondOperand.getOperand(1))) ||
955         !isShiftedMask_64(CN->getZExtValue(), SMPos1, SMSize1))
956       return SDValue();
957 
958     // The shift masks must have the same position and size.
959     if (SMPos0 != SMPos1 || SMSize0 != SMSize1)
960       return SDValue();
961 
962     SDValue Shl = SecondOperand.getOperand(0);
963 
964     if (!(CN = dyn_cast<ConstantSDNode>(Shl.getOperand(1))))
965       return SDValue();
966 
967     unsigned Shamt = CN->getZExtValue();
968 
969     // Return if the shift amount and the first bit position of mask are not the
970     // same.
971     EVT ValTy = N->getValueType(0);
972     if ((Shamt != SMPos0) || (SMPos0 + SMSize0 > ValTy.getSizeInBits()))
973       return SDValue();
974 
975     SDLoc DL(N);
976     return DAG.getNode(MipsISD::Ins, DL, ValTy, Shl.getOperand(0),
977                        DAG.getConstant(SMPos0, DL, MVT::i32),
978                        DAG.getConstant(SMSize0, DL, MVT::i32),
979                        FirstOperand.getOperand(0));
980   } else {
981     // Pattern match DINS.
982     //  $dst = or (and $src, mask0), mask1
983     //  where mask0 = ((1 << SMSize0) -1) << SMPos0
984     //  => dins $dst, $src, pos, size
985     if (~CN->getSExtValue() == ((((int64_t)1 << SMSize0) - 1) << SMPos0) &&
986         ((SMSize0 + SMPos0 <= 64 && Subtarget.hasMips64r2()) ||
987          (SMSize0 + SMPos0 <= 32))) {
988       // Check if AND instruction has constant as argument
989       bool isConstCase = SecondOperand.getOpcode() != ISD::AND;
990       if (SecondOperand.getOpcode() == ISD::AND) {
991         if (!(CN1 = dyn_cast<ConstantSDNode>(SecondOperand->getOperand(1))))
992           return SDValue();
993       } else {
994         if (!(CN1 = dyn_cast<ConstantSDNode>(N->getOperand(1))))
995           return SDValue();
996       }
997       // Don't generate INS if constant OR operand doesn't fit into bits
998       // cleared by constant AND operand.
999       if (CN->getSExtValue() & CN1->getSExtValue())
1000         return SDValue();
1001 
1002       SDLoc DL(N);
1003       EVT ValTy = N->getOperand(0)->getValueType(0);
1004       SDValue Const1;
1005       SDValue SrlX;
1006       if (!isConstCase) {
1007         Const1 = DAG.getConstant(SMPos0, DL, MVT::i32);
1008         SrlX = DAG.getNode(ISD::SRL, DL, SecondOperand->getValueType(0),
1009                            SecondOperand, Const1);
1010       }
1011       return DAG.getNode(
1012           MipsISD::Ins, DL, N->getValueType(0),
1013           isConstCase
1014               ? DAG.getSignedConstant(CN1->getSExtValue() >> SMPos0, DL, ValTy)
1015               : SrlX,
1016           DAG.getConstant(SMPos0, DL, MVT::i32),
1017           DAG.getConstant(ValTy.getSizeInBits() / 8 < 8 ? SMSize0 & 31
1018                                                         : SMSize0,
1019                           DL, MVT::i32),
1020           FirstOperand->getOperand(0));
1021     }
1022     return SDValue();
1023   }
1024 }
1025 
performMADD_MSUBCombine(SDNode * ROOTNode,SelectionDAG & CurDAG,const MipsSubtarget & Subtarget)1026 static SDValue performMADD_MSUBCombine(SDNode *ROOTNode, SelectionDAG &CurDAG,
1027                                        const MipsSubtarget &Subtarget) {
1028   // ROOTNode must have a multiplication as an operand for the match to be
1029   // successful.
1030   if (ROOTNode->getOperand(0).getOpcode() != ISD::MUL &&
1031       ROOTNode->getOperand(1).getOpcode() != ISD::MUL)
1032     return SDValue();
1033 
1034   // In the case where we have a multiplication as the left operand of
1035   // of a subtraction, we can't combine into a MipsISD::MSub node as the
1036   // the instruction definition of msub(u) places the multiplication on
1037   // on the right.
1038   if (ROOTNode->getOpcode() == ISD::SUB &&
1039       ROOTNode->getOperand(0).getOpcode() == ISD::MUL)
1040     return SDValue();
1041 
1042   // We don't handle vector types here.
1043   if (ROOTNode->getValueType(0).isVector())
1044     return SDValue();
1045 
1046   // For MIPS64, madd / msub instructions are inefficent to use with 64 bit
1047   // arithmetic. E.g.
1048   // (add (mul a b) c) =>
1049   //   let res = (madd (mthi (drotr c 32))x(mtlo c) a b) in
1050   //   MIPS64:   (or (dsll (mfhi res) 32) (dsrl (dsll (mflo res) 32) 32)
1051   //   or
1052   //   MIPS64R2: (dins (mflo res) (mfhi res) 32 32)
1053   //
1054   // The overhead of setting up the Hi/Lo registers and reassembling the
1055   // result makes this a dubious optimzation for MIPS64. The core of the
1056   // problem is that Hi/Lo contain the upper and lower 32 bits of the
1057   // operand and result.
1058   //
1059   // It requires a chain of 4 add/mul for MIPS64R2 to get better code
1060   // density than doing it naively, 5 for MIPS64. Additionally, using
1061   // madd/msub on MIPS64 requires the operands actually be 32 bit sign
1062   // extended operands, not true 64 bit values.
1063   //
1064   // FIXME: For the moment, disable this completely for MIPS64.
1065   if (Subtarget.hasMips64())
1066     return SDValue();
1067 
1068   SDValue Mult = ROOTNode->getOperand(0).getOpcode() == ISD::MUL
1069                      ? ROOTNode->getOperand(0)
1070                      : ROOTNode->getOperand(1);
1071 
1072   SDValue AddOperand = ROOTNode->getOperand(0).getOpcode() == ISD::MUL
1073                      ? ROOTNode->getOperand(1)
1074                      : ROOTNode->getOperand(0);
1075 
1076   // Transform this to a MADD only if the user of this node is the add.
1077   // If there are other users of the mul, this function returns here.
1078   if (!Mult.hasOneUse())
1079     return SDValue();
1080 
1081   // maddu and madd are unusual instructions in that on MIPS64 bits 63..31
1082   // must be in canonical form, i.e. sign extended. For MIPS32, the operands
1083   // of the multiply must have 32 or more sign bits, otherwise we cannot
1084   // perform this optimization. We have to check this here as we're performing
1085   // this optimization pre-legalization.
1086   SDValue MultLHS = Mult->getOperand(0);
1087   SDValue MultRHS = Mult->getOperand(1);
1088 
1089   bool IsSigned = MultLHS->getOpcode() == ISD::SIGN_EXTEND &&
1090                   MultRHS->getOpcode() == ISD::SIGN_EXTEND;
1091   bool IsUnsigned = MultLHS->getOpcode() == ISD::ZERO_EXTEND &&
1092                     MultRHS->getOpcode() == ISD::ZERO_EXTEND;
1093 
1094   if (!IsSigned && !IsUnsigned)
1095     return SDValue();
1096 
1097   // Initialize accumulator.
1098   SDLoc DL(ROOTNode);
1099   SDValue BottomHalf, TopHalf;
1100   std::tie(BottomHalf, TopHalf) =
1101       CurDAG.SplitScalar(AddOperand, DL, MVT::i32, MVT::i32);
1102   SDValue ACCIn =
1103       CurDAG.getNode(MipsISD::MTLOHI, DL, MVT::Untyped, BottomHalf, TopHalf);
1104 
1105   // Create MipsMAdd(u) / MipsMSub(u) node.
1106   bool IsAdd = ROOTNode->getOpcode() == ISD::ADD;
1107   unsigned Opcode = IsAdd ? (IsUnsigned ? MipsISD::MAddu : MipsISD::MAdd)
1108                           : (IsUnsigned ? MipsISD::MSubu : MipsISD::MSub);
1109   SDValue MAddOps[3] = {
1110       CurDAG.getNode(ISD::TRUNCATE, DL, MVT::i32, Mult->getOperand(0)),
1111       CurDAG.getNode(ISD::TRUNCATE, DL, MVT::i32, Mult->getOperand(1)), ACCIn};
1112   SDValue MAdd = CurDAG.getNode(Opcode, DL, MVT::Untyped, MAddOps);
1113 
1114   SDValue ResLo = CurDAG.getNode(MipsISD::MFLO, DL, MVT::i32, MAdd);
1115   SDValue ResHi = CurDAG.getNode(MipsISD::MFHI, DL, MVT::i32, MAdd);
1116   SDValue Combined =
1117       CurDAG.getNode(ISD::BUILD_PAIR, DL, MVT::i64, ResLo, ResHi);
1118   return Combined;
1119 }
1120 
performSUBCombine(SDNode * N,SelectionDAG & DAG,TargetLowering::DAGCombinerInfo & DCI,const MipsSubtarget & Subtarget)1121 static SDValue performSUBCombine(SDNode *N, SelectionDAG &DAG,
1122                                  TargetLowering::DAGCombinerInfo &DCI,
1123                                  const MipsSubtarget &Subtarget) {
1124   // (sub v0 (mul v1, v2)) => (msub v1, v2, v0)
1125   if (DCI.isBeforeLegalizeOps()) {
1126     if (Subtarget.hasMips32() && !Subtarget.hasMips32r6() &&
1127         !Subtarget.inMips16Mode() && N->getValueType(0) == MVT::i64)
1128       return performMADD_MSUBCombine(N, DAG, Subtarget);
1129 
1130     return SDValue();
1131   }
1132 
1133   return SDValue();
1134 }
1135 
performADDCombine(SDNode * N,SelectionDAG & DAG,TargetLowering::DAGCombinerInfo & DCI,const MipsSubtarget & Subtarget)1136 static SDValue performADDCombine(SDNode *N, SelectionDAG &DAG,
1137                                  TargetLowering::DAGCombinerInfo &DCI,
1138                                  const MipsSubtarget &Subtarget) {
1139   // (add v0 (mul v1, v2)) => (madd v1, v2, v0)
1140   if (DCI.isBeforeLegalizeOps()) {
1141     if (Subtarget.hasMips32() && !Subtarget.hasMips32r6() &&
1142         !Subtarget.inMips16Mode() && N->getValueType(0) == MVT::i64)
1143       return performMADD_MSUBCombine(N, DAG, Subtarget);
1144 
1145     return SDValue();
1146   }
1147 
1148   // When loading from a jump table, push the Lo node to the position that
1149   // allows folding it into a load immediate.
1150   // (add v0, (add v1, abs_lo(tjt))) => (add (add v0, v1), abs_lo(tjt))
1151   // (add (add abs_lo(tjt), v1), v0) => (add (add v0, v1), abs_lo(tjt))
1152   SDValue InnerAdd = N->getOperand(1);
1153   SDValue Index = N->getOperand(0);
1154   if (InnerAdd.getOpcode() != ISD::ADD)
1155     std::swap(InnerAdd, Index);
1156   if (InnerAdd.getOpcode() != ISD::ADD)
1157     return SDValue();
1158 
1159   SDValue Lo = InnerAdd.getOperand(0);
1160   SDValue Other = InnerAdd.getOperand(1);
1161   if (Lo.getOpcode() != MipsISD::Lo)
1162     std::swap(Lo, Other);
1163 
1164   if ((Lo.getOpcode() != MipsISD::Lo) ||
1165       (Lo.getOperand(0).getOpcode() != ISD::TargetJumpTable))
1166     return SDValue();
1167 
1168   EVT ValTy = N->getValueType(0);
1169   SDLoc DL(N);
1170 
1171   SDValue Add1 = DAG.getNode(ISD::ADD, DL, ValTy, Index, Other);
1172   return DAG.getNode(ISD::ADD, DL, ValTy, Add1, Lo);
1173 }
1174 
performSHLCombine(SDNode * N,SelectionDAG & DAG,TargetLowering::DAGCombinerInfo & DCI,const MipsSubtarget & Subtarget)1175 static SDValue performSHLCombine(SDNode *N, SelectionDAG &DAG,
1176                                  TargetLowering::DAGCombinerInfo &DCI,
1177                                  const MipsSubtarget &Subtarget) {
1178   // Pattern match CINS.
1179   //  $dst = shl (and $src , imm), pos
1180   //  => cins $dst, $src, pos, size
1181 
1182   if (DCI.isBeforeLegalizeOps() || !Subtarget.hasCnMips())
1183     return SDValue();
1184 
1185   SDValue FirstOperand = N->getOperand(0);
1186   unsigned FirstOperandOpc = FirstOperand.getOpcode();
1187   SDValue SecondOperand = N->getOperand(1);
1188   EVT ValTy = N->getValueType(0);
1189   SDLoc DL(N);
1190 
1191   uint64_t Pos = 0;
1192   unsigned SMPos, SMSize;
1193   ConstantSDNode *CN;
1194   SDValue NewOperand;
1195 
1196   // The second operand of the shift must be an immediate.
1197   if (!(CN = dyn_cast<ConstantSDNode>(SecondOperand)))
1198     return SDValue();
1199 
1200   Pos = CN->getZExtValue();
1201 
1202   if (Pos >= ValTy.getSizeInBits())
1203     return SDValue();
1204 
1205   if (FirstOperandOpc != ISD::AND)
1206     return SDValue();
1207 
1208   // AND's second operand must be a shifted mask.
1209   if (!(CN = dyn_cast<ConstantSDNode>(FirstOperand.getOperand(1))) ||
1210       !isShiftedMask_64(CN->getZExtValue(), SMPos, SMSize))
1211     return SDValue();
1212 
1213   // Return if the shifted mask does not start at bit 0 or the sum of its size
1214   // and Pos exceeds the word's size.
1215   if (SMPos != 0 || SMSize > 32 || Pos + SMSize > ValTy.getSizeInBits())
1216     return SDValue();
1217 
1218   NewOperand = FirstOperand.getOperand(0);
1219   // SMSize is 'location' (position) in this case, not size.
1220   SMSize--;
1221 
1222   return DAG.getNode(MipsISD::CIns, DL, ValTy, NewOperand,
1223                      DAG.getConstant(Pos, DL, MVT::i32),
1224                      DAG.getConstant(SMSize, DL, MVT::i32));
1225 }
1226 
performSignExtendCombine(SDNode * N,SelectionDAG & DAG,TargetLowering::DAGCombinerInfo & DCI,const MipsSubtarget & Subtarget)1227 static SDValue performSignExtendCombine(SDNode *N, SelectionDAG &DAG,
1228                                         TargetLowering::DAGCombinerInfo &DCI,
1229                                         const MipsSubtarget &Subtarget) {
1230   if (DCI.Level != AfterLegalizeDAG || !Subtarget.isGP64bit()) {
1231     return SDValue();
1232   }
1233 
1234   SDValue N0 = N->getOperand(0);
1235   EVT VT = N->getValueType(0);
1236 
1237   // Pattern match XOR.
1238   // $dst = sign_extend (xor (trunc $src, i32), imm)
1239   // => $dst = xor (signext_inreg $src, i32), imm
1240   if (N0.getOpcode() == ISD::XOR &&
1241       N0.getOperand(0).getOpcode() == ISD::TRUNCATE &&
1242       N0.getOperand(1).getOpcode() == ISD::Constant) {
1243     SDValue TruncateSource = N0.getOperand(0).getOperand(0);
1244     auto *ConstantOperand = dyn_cast<ConstantSDNode>(N0->getOperand(1));
1245 
1246     SDValue FirstOperand =
1247         DAG.getNode(ISD::SIGN_EXTEND_INREG, SDLoc(N0), VT, TruncateSource,
1248                     DAG.getValueType(N0.getOperand(0).getValueType()));
1249 
1250     int64_t ConstImm = ConstantOperand->getSExtValue();
1251     return DAG.getNode(ISD::XOR, SDLoc(N0), VT, FirstOperand,
1252                        DAG.getConstant(ConstImm, SDLoc(N0), VT));
1253   }
1254 
1255   return SDValue();
1256 }
1257 
PerformDAGCombine(SDNode * N,DAGCombinerInfo & DCI) const1258 SDValue  MipsTargetLowering::PerformDAGCombine(SDNode *N, DAGCombinerInfo &DCI)
1259   const {
1260   SelectionDAG &DAG = DCI.DAG;
1261   unsigned Opc = N->getOpcode();
1262 
1263   switch (Opc) {
1264   default: break;
1265   case ISD::SDIVREM:
1266   case ISD::UDIVREM:
1267     return performDivRemCombine(N, DAG, DCI, Subtarget);
1268   case ISD::SELECT:
1269     return performSELECTCombine(N, DAG, DCI, Subtarget);
1270   case MipsISD::CMovFP_F:
1271   case MipsISD::CMovFP_T:
1272     return performCMovFPCombine(N, DAG, DCI, Subtarget);
1273   case ISD::AND:
1274     return performANDCombine(N, DAG, DCI, Subtarget);
1275   case ISD::OR:
1276     return performORCombine(N, DAG, DCI, Subtarget);
1277   case ISD::ADD:
1278     return performADDCombine(N, DAG, DCI, Subtarget);
1279   case ISD::SHL:
1280     return performSHLCombine(N, DAG, DCI, Subtarget);
1281   case ISD::SUB:
1282     return performSUBCombine(N, DAG, DCI, Subtarget);
1283   case ISD::SIGN_EXTEND:
1284     return performSignExtendCombine(N, DAG, DCI, Subtarget);
1285   }
1286 
1287   return SDValue();
1288 }
1289 
isCheapToSpeculateCttz(Type * Ty) const1290 bool MipsTargetLowering::isCheapToSpeculateCttz(Type *Ty) const {
1291   return Subtarget.hasMips32();
1292 }
1293 
isCheapToSpeculateCtlz(Type * Ty) const1294 bool MipsTargetLowering::isCheapToSpeculateCtlz(Type *Ty) const {
1295   return Subtarget.hasMips32();
1296 }
1297 
hasBitTest(SDValue X,SDValue Y) const1298 bool MipsTargetLowering::hasBitTest(SDValue X, SDValue Y) const {
1299   // We can use ANDI+SLTIU as a bit test. Y contains the bit position.
1300   // For MIPSR2 or later, we may be able to use the `ext` instruction or its'
1301   // double-word variants.
1302   if (auto *C = dyn_cast<ConstantSDNode>(Y))
1303     return C->getAPIntValue().ule(15);
1304 
1305   return false;
1306 }
1307 
shouldFoldConstantShiftPairToMask(const SDNode * N,CombineLevel Level) const1308 bool MipsTargetLowering::shouldFoldConstantShiftPairToMask(
1309     const SDNode *N, CombineLevel Level) const {
1310   assert(((N->getOpcode() == ISD::SHL &&
1311            N->getOperand(0).getOpcode() == ISD::SRL) ||
1312           (N->getOpcode() == ISD::SRL &&
1313            N->getOperand(0).getOpcode() == ISD::SHL)) &&
1314          "Expected shift-shift mask");
1315 
1316   if (N->getOperand(0).getValueType().isVector())
1317     return false;
1318   return true;
1319 }
1320 
1321 void
ReplaceNodeResults(SDNode * N,SmallVectorImpl<SDValue> & Results,SelectionDAG & DAG) const1322 MipsTargetLowering::ReplaceNodeResults(SDNode *N,
1323                                        SmallVectorImpl<SDValue> &Results,
1324                                        SelectionDAG &DAG) const {
1325   return LowerOperationWrapper(N, Results, DAG);
1326 }
1327 
1328 SDValue MipsTargetLowering::
LowerOperation(SDValue Op,SelectionDAG & DAG) const1329 LowerOperation(SDValue Op, SelectionDAG &DAG) const
1330 {
1331   switch (Op.getOpcode())
1332   {
1333   case ISD::BRCOND:             return lowerBRCOND(Op, DAG);
1334   case ISD::ConstantPool:       return lowerConstantPool(Op, DAG);
1335   case ISD::GlobalAddress:      return lowerGlobalAddress(Op, DAG);
1336   case ISD::BlockAddress:       return lowerBlockAddress(Op, DAG);
1337   case ISD::GlobalTLSAddress:   return lowerGlobalTLSAddress(Op, DAG);
1338   case ISD::JumpTable:          return lowerJumpTable(Op, DAG);
1339   case ISD::SELECT:             return lowerSELECT(Op, DAG);
1340   case ISD::SETCC:              return lowerSETCC(Op, DAG);
1341   case ISD::VASTART:            return lowerVASTART(Op, DAG);
1342   case ISD::VAARG:              return lowerVAARG(Op, DAG);
1343   case ISD::FCOPYSIGN:          return lowerFCOPYSIGN(Op, DAG);
1344   case ISD::FABS:               return lowerFABS(Op, DAG);
1345   case ISD::FCANONICALIZE:
1346     return lowerFCANONICALIZE(Op, DAG);
1347   case ISD::FRAMEADDR:          return lowerFRAMEADDR(Op, DAG);
1348   case ISD::RETURNADDR:         return lowerRETURNADDR(Op, DAG);
1349   case ISD::EH_RETURN:          return lowerEH_RETURN(Op, DAG);
1350   case ISD::ATOMIC_FENCE:       return lowerATOMIC_FENCE(Op, DAG);
1351   case ISD::SHL_PARTS:          return lowerShiftLeftParts(Op, DAG);
1352   case ISD::SRA_PARTS:          return lowerShiftRightParts(Op, DAG, true);
1353   case ISD::SRL_PARTS:          return lowerShiftRightParts(Op, DAG, false);
1354   case ISD::LOAD:               return lowerLOAD(Op, DAG);
1355   case ISD::STORE:              return lowerSTORE(Op, DAG);
1356   case ISD::EH_DWARF_CFA:       return lowerEH_DWARF_CFA(Op, DAG);
1357   case ISD::FP_TO_SINT:         return lowerFP_TO_SINT(Op, DAG);
1358   case ISD::READCYCLECOUNTER:
1359     return lowerREADCYCLECOUNTER(Op, DAG);
1360   }
1361   return SDValue();
1362 }
1363 
1364 //===----------------------------------------------------------------------===//
1365 //  Lower helper functions
1366 //===----------------------------------------------------------------------===//
1367 
1368 // addLiveIn - This helper function adds the specified physical register to the
1369 // MachineFunction as a live in value.  It also creates a corresponding
1370 // virtual register for it.
1371 static unsigned
addLiveIn(MachineFunction & MF,unsigned PReg,const TargetRegisterClass * RC)1372 addLiveIn(MachineFunction &MF, unsigned PReg, const TargetRegisterClass *RC)
1373 {
1374   Register VReg = MF.getRegInfo().createVirtualRegister(RC);
1375   MF.getRegInfo().addLiveIn(PReg, VReg);
1376   return VReg;
1377 }
1378 
insertDivByZeroTrap(MachineInstr & MI,MachineBasicBlock & MBB,const TargetInstrInfo & TII,bool Is64Bit,bool IsMicroMips)1379 static MachineBasicBlock *insertDivByZeroTrap(MachineInstr &MI,
1380                                               MachineBasicBlock &MBB,
1381                                               const TargetInstrInfo &TII,
1382                                               bool Is64Bit, bool IsMicroMips) {
1383   if (NoZeroDivCheck)
1384     return &MBB;
1385 
1386   // Insert instruction "teq $divisor_reg, $zero, 7".
1387   MachineBasicBlock::iterator I(MI);
1388   MachineInstrBuilder MIB;
1389   MachineOperand &Divisor = MI.getOperand(2);
1390   MIB = BuildMI(MBB, std::next(I), MI.getDebugLoc(),
1391                 TII.get(IsMicroMips ? Mips::TEQ_MM : Mips::TEQ))
1392             .addReg(Divisor.getReg(), getKillRegState(Divisor.isKill()))
1393             .addReg(Mips::ZERO)
1394             .addImm(7);
1395 
1396   // Use the 32-bit sub-register if this is a 64-bit division.
1397   if (Is64Bit)
1398     MIB->getOperand(0).setSubReg(Mips::sub_32);
1399 
1400   // Clear Divisor's kill flag.
1401   Divisor.setIsKill(false);
1402 
1403   // We would normally delete the original instruction here but in this case
1404   // we only needed to inject an additional instruction rather than replace it.
1405 
1406   return &MBB;
1407 }
1408 
1409 MachineBasicBlock *
EmitInstrWithCustomInserter(MachineInstr & MI,MachineBasicBlock * BB) const1410 MipsTargetLowering::EmitInstrWithCustomInserter(MachineInstr &MI,
1411                                                 MachineBasicBlock *BB) const {
1412   switch (MI.getOpcode()) {
1413   default:
1414     llvm_unreachable("Unexpected instr type to insert");
1415   case Mips::ATOMIC_LOAD_ADD_I8:
1416     return emitAtomicBinaryPartword(MI, BB, 1);
1417   case Mips::ATOMIC_LOAD_ADD_I16:
1418     return emitAtomicBinaryPartword(MI, BB, 2);
1419   case Mips::ATOMIC_LOAD_ADD_I32:
1420     return emitAtomicBinary(MI, BB);
1421   case Mips::ATOMIC_LOAD_ADD_I64:
1422     return emitAtomicBinary(MI, BB);
1423 
1424   case Mips::ATOMIC_LOAD_AND_I8:
1425     return emitAtomicBinaryPartword(MI, BB, 1);
1426   case Mips::ATOMIC_LOAD_AND_I16:
1427     return emitAtomicBinaryPartword(MI, BB, 2);
1428   case Mips::ATOMIC_LOAD_AND_I32:
1429     return emitAtomicBinary(MI, BB);
1430   case Mips::ATOMIC_LOAD_AND_I64:
1431     return emitAtomicBinary(MI, BB);
1432 
1433   case Mips::ATOMIC_LOAD_OR_I8:
1434     return emitAtomicBinaryPartword(MI, BB, 1);
1435   case Mips::ATOMIC_LOAD_OR_I16:
1436     return emitAtomicBinaryPartword(MI, BB, 2);
1437   case Mips::ATOMIC_LOAD_OR_I32:
1438     return emitAtomicBinary(MI, BB);
1439   case Mips::ATOMIC_LOAD_OR_I64:
1440     return emitAtomicBinary(MI, BB);
1441 
1442   case Mips::ATOMIC_LOAD_XOR_I8:
1443     return emitAtomicBinaryPartword(MI, BB, 1);
1444   case Mips::ATOMIC_LOAD_XOR_I16:
1445     return emitAtomicBinaryPartword(MI, BB, 2);
1446   case Mips::ATOMIC_LOAD_XOR_I32:
1447     return emitAtomicBinary(MI, BB);
1448   case Mips::ATOMIC_LOAD_XOR_I64:
1449     return emitAtomicBinary(MI, BB);
1450 
1451   case Mips::ATOMIC_LOAD_NAND_I8:
1452     return emitAtomicBinaryPartword(MI, BB, 1);
1453   case Mips::ATOMIC_LOAD_NAND_I16:
1454     return emitAtomicBinaryPartword(MI, BB, 2);
1455   case Mips::ATOMIC_LOAD_NAND_I32:
1456     return emitAtomicBinary(MI, BB);
1457   case Mips::ATOMIC_LOAD_NAND_I64:
1458     return emitAtomicBinary(MI, BB);
1459 
1460   case Mips::ATOMIC_LOAD_SUB_I8:
1461     return emitAtomicBinaryPartword(MI, BB, 1);
1462   case Mips::ATOMIC_LOAD_SUB_I16:
1463     return emitAtomicBinaryPartword(MI, BB, 2);
1464   case Mips::ATOMIC_LOAD_SUB_I32:
1465     return emitAtomicBinary(MI, BB);
1466   case Mips::ATOMIC_LOAD_SUB_I64:
1467     return emitAtomicBinary(MI, BB);
1468 
1469   case Mips::ATOMIC_SWAP_I8:
1470     return emitAtomicBinaryPartword(MI, BB, 1);
1471   case Mips::ATOMIC_SWAP_I16:
1472     return emitAtomicBinaryPartword(MI, BB, 2);
1473   case Mips::ATOMIC_SWAP_I32:
1474     return emitAtomicBinary(MI, BB);
1475   case Mips::ATOMIC_SWAP_I64:
1476     return emitAtomicBinary(MI, BB);
1477 
1478   case Mips::ATOMIC_CMP_SWAP_I8:
1479     return emitAtomicCmpSwapPartword(MI, BB, 1);
1480   case Mips::ATOMIC_CMP_SWAP_I16:
1481     return emitAtomicCmpSwapPartword(MI, BB, 2);
1482   case Mips::ATOMIC_CMP_SWAP_I32:
1483     return emitAtomicCmpSwap(MI, BB);
1484   case Mips::ATOMIC_CMP_SWAP_I64:
1485     return emitAtomicCmpSwap(MI, BB);
1486 
1487   case Mips::ATOMIC_LOAD_MIN_I8:
1488     return emitAtomicBinaryPartword(MI, BB, 1);
1489   case Mips::ATOMIC_LOAD_MIN_I16:
1490     return emitAtomicBinaryPartword(MI, BB, 2);
1491   case Mips::ATOMIC_LOAD_MIN_I32:
1492     return emitAtomicBinary(MI, BB);
1493   case Mips::ATOMIC_LOAD_MIN_I64:
1494     return emitAtomicBinary(MI, BB);
1495 
1496   case Mips::ATOMIC_LOAD_MAX_I8:
1497     return emitAtomicBinaryPartword(MI, BB, 1);
1498   case Mips::ATOMIC_LOAD_MAX_I16:
1499     return emitAtomicBinaryPartword(MI, BB, 2);
1500   case Mips::ATOMIC_LOAD_MAX_I32:
1501     return emitAtomicBinary(MI, BB);
1502   case Mips::ATOMIC_LOAD_MAX_I64:
1503     return emitAtomicBinary(MI, BB);
1504 
1505   case Mips::ATOMIC_LOAD_UMIN_I8:
1506     return emitAtomicBinaryPartword(MI, BB, 1);
1507   case Mips::ATOMIC_LOAD_UMIN_I16:
1508     return emitAtomicBinaryPartword(MI, BB, 2);
1509   case Mips::ATOMIC_LOAD_UMIN_I32:
1510     return emitAtomicBinary(MI, BB);
1511   case Mips::ATOMIC_LOAD_UMIN_I64:
1512     return emitAtomicBinary(MI, BB);
1513 
1514   case Mips::ATOMIC_LOAD_UMAX_I8:
1515     return emitAtomicBinaryPartword(MI, BB, 1);
1516   case Mips::ATOMIC_LOAD_UMAX_I16:
1517     return emitAtomicBinaryPartword(MI, BB, 2);
1518   case Mips::ATOMIC_LOAD_UMAX_I32:
1519     return emitAtomicBinary(MI, BB);
1520   case Mips::ATOMIC_LOAD_UMAX_I64:
1521     return emitAtomicBinary(MI, BB);
1522 
1523   case Mips::PseudoSDIV:
1524   case Mips::PseudoUDIV:
1525   case Mips::DIV:
1526   case Mips::DIVU:
1527   case Mips::MOD:
1528   case Mips::MODU:
1529     return insertDivByZeroTrap(MI, *BB, *Subtarget.getInstrInfo(), false,
1530                                false);
1531   case Mips::SDIV_MM_Pseudo:
1532   case Mips::UDIV_MM_Pseudo:
1533   case Mips::SDIV_MM:
1534   case Mips::UDIV_MM:
1535   case Mips::DIV_MMR6:
1536   case Mips::DIVU_MMR6:
1537   case Mips::MOD_MMR6:
1538   case Mips::MODU_MMR6:
1539     return insertDivByZeroTrap(MI, *BB, *Subtarget.getInstrInfo(), false, true);
1540   case Mips::PseudoDSDIV:
1541   case Mips::PseudoDUDIV:
1542   case Mips::DDIV:
1543   case Mips::DDIVU:
1544   case Mips::DMOD:
1545   case Mips::DMODU:
1546     return insertDivByZeroTrap(MI, *BB, *Subtarget.getInstrInfo(), true, false);
1547 
1548   case Mips::PseudoSELECT_I:
1549   case Mips::PseudoSELECT_I64:
1550   case Mips::PseudoSELECT_S:
1551   case Mips::PseudoSELECT_D32:
1552   case Mips::PseudoSELECT_D64:
1553     return emitPseudoSELECT(MI, BB, false, Mips::BNE);
1554   case Mips::PseudoSELECTFP_F_I:
1555   case Mips::PseudoSELECTFP_F_I64:
1556   case Mips::PseudoSELECTFP_F_S:
1557   case Mips::PseudoSELECTFP_F_D32:
1558   case Mips::PseudoSELECTFP_F_D64:
1559     return emitPseudoSELECT(MI, BB, true, Mips::BC1F);
1560   case Mips::PseudoSELECTFP_T_I:
1561   case Mips::PseudoSELECTFP_T_I64:
1562   case Mips::PseudoSELECTFP_T_S:
1563   case Mips::PseudoSELECTFP_T_D32:
1564   case Mips::PseudoSELECTFP_T_D64:
1565     return emitPseudoSELECT(MI, BB, true, Mips::BC1T);
1566   case Mips::PseudoD_SELECT_I:
1567   case Mips::PseudoD_SELECT_I64:
1568     return emitPseudoD_SELECT(MI, BB);
1569   case Mips::LDR_W:
1570     return emitLDR_W(MI, BB);
1571   case Mips::LDR_D:
1572     return emitLDR_D(MI, BB);
1573   case Mips::STR_W:
1574     return emitSTR_W(MI, BB);
1575   case Mips::STR_D:
1576     return emitSTR_D(MI, BB);
1577   }
1578 }
1579 
1580 // This function also handles Mips::ATOMIC_SWAP_I32 (when BinOpcode == 0), and
1581 // Mips::ATOMIC_LOAD_NAND_I32 (when Nand == true)
1582 MachineBasicBlock *
emitAtomicBinary(MachineInstr & MI,MachineBasicBlock * BB) const1583 MipsTargetLowering::emitAtomicBinary(MachineInstr &MI,
1584                                      MachineBasicBlock *BB) const {
1585 
1586   MachineFunction *MF = BB->getParent();
1587   MachineRegisterInfo &RegInfo = MF->getRegInfo();
1588   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
1589   DebugLoc DL = MI.getDebugLoc();
1590 
1591   unsigned AtomicOp;
1592   bool NeedsAdditionalReg = false;
1593   switch (MI.getOpcode()) {
1594   case Mips::ATOMIC_LOAD_ADD_I32:
1595     AtomicOp = Mips::ATOMIC_LOAD_ADD_I32_POSTRA;
1596     break;
1597   case Mips::ATOMIC_LOAD_SUB_I32:
1598     AtomicOp = Mips::ATOMIC_LOAD_SUB_I32_POSTRA;
1599     break;
1600   case Mips::ATOMIC_LOAD_AND_I32:
1601     AtomicOp = Mips::ATOMIC_LOAD_AND_I32_POSTRA;
1602     break;
1603   case Mips::ATOMIC_LOAD_OR_I32:
1604     AtomicOp = Mips::ATOMIC_LOAD_OR_I32_POSTRA;
1605     break;
1606   case Mips::ATOMIC_LOAD_XOR_I32:
1607     AtomicOp = Mips::ATOMIC_LOAD_XOR_I32_POSTRA;
1608     break;
1609   case Mips::ATOMIC_LOAD_NAND_I32:
1610     AtomicOp = Mips::ATOMIC_LOAD_NAND_I32_POSTRA;
1611     break;
1612   case Mips::ATOMIC_SWAP_I32:
1613     AtomicOp = Mips::ATOMIC_SWAP_I32_POSTRA;
1614     break;
1615   case Mips::ATOMIC_LOAD_ADD_I64:
1616     AtomicOp = Mips::ATOMIC_LOAD_ADD_I64_POSTRA;
1617     break;
1618   case Mips::ATOMIC_LOAD_SUB_I64:
1619     AtomicOp = Mips::ATOMIC_LOAD_SUB_I64_POSTRA;
1620     break;
1621   case Mips::ATOMIC_LOAD_AND_I64:
1622     AtomicOp = Mips::ATOMIC_LOAD_AND_I64_POSTRA;
1623     break;
1624   case Mips::ATOMIC_LOAD_OR_I64:
1625     AtomicOp = Mips::ATOMIC_LOAD_OR_I64_POSTRA;
1626     break;
1627   case Mips::ATOMIC_LOAD_XOR_I64:
1628     AtomicOp = Mips::ATOMIC_LOAD_XOR_I64_POSTRA;
1629     break;
1630   case Mips::ATOMIC_LOAD_NAND_I64:
1631     AtomicOp = Mips::ATOMIC_LOAD_NAND_I64_POSTRA;
1632     break;
1633   case Mips::ATOMIC_SWAP_I64:
1634     AtomicOp = Mips::ATOMIC_SWAP_I64_POSTRA;
1635     break;
1636   case Mips::ATOMIC_LOAD_MIN_I32:
1637     AtomicOp = Mips::ATOMIC_LOAD_MIN_I32_POSTRA;
1638     NeedsAdditionalReg = true;
1639     break;
1640   case Mips::ATOMIC_LOAD_MAX_I32:
1641     AtomicOp = Mips::ATOMIC_LOAD_MAX_I32_POSTRA;
1642     NeedsAdditionalReg = true;
1643     break;
1644   case Mips::ATOMIC_LOAD_UMIN_I32:
1645     AtomicOp = Mips::ATOMIC_LOAD_UMIN_I32_POSTRA;
1646     NeedsAdditionalReg = true;
1647     break;
1648   case Mips::ATOMIC_LOAD_UMAX_I32:
1649     AtomicOp = Mips::ATOMIC_LOAD_UMAX_I32_POSTRA;
1650     NeedsAdditionalReg = true;
1651     break;
1652   case Mips::ATOMIC_LOAD_MIN_I64:
1653     AtomicOp = Mips::ATOMIC_LOAD_MIN_I64_POSTRA;
1654     NeedsAdditionalReg = true;
1655     break;
1656   case Mips::ATOMIC_LOAD_MAX_I64:
1657     AtomicOp = Mips::ATOMIC_LOAD_MAX_I64_POSTRA;
1658     NeedsAdditionalReg = true;
1659     break;
1660   case Mips::ATOMIC_LOAD_UMIN_I64:
1661     AtomicOp = Mips::ATOMIC_LOAD_UMIN_I64_POSTRA;
1662     NeedsAdditionalReg = true;
1663     break;
1664   case Mips::ATOMIC_LOAD_UMAX_I64:
1665     AtomicOp = Mips::ATOMIC_LOAD_UMAX_I64_POSTRA;
1666     NeedsAdditionalReg = true;
1667     break;
1668   default:
1669     llvm_unreachable("Unknown pseudo atomic for replacement!");
1670   }
1671 
1672   Register OldVal = MI.getOperand(0).getReg();
1673   Register Ptr = MI.getOperand(1).getReg();
1674   Register Incr = MI.getOperand(2).getReg();
1675   Register Scratch = RegInfo.createVirtualRegister(RegInfo.getRegClass(OldVal));
1676 
1677   MachineBasicBlock::iterator II(MI);
1678 
1679   // The scratch registers here with the EarlyClobber | Define | Implicit
1680   // flags is used to persuade the register allocator and the machine
1681   // verifier to accept the usage of this register. This has to be a real
1682   // register which has an UNDEF value but is dead after the instruction which
1683   // is unique among the registers chosen for the instruction.
1684 
1685   // The EarlyClobber flag has the semantic properties that the operand it is
1686   // attached to is clobbered before the rest of the inputs are read. Hence it
1687   // must be unique among the operands to the instruction.
1688   // The Define flag is needed to coerce the machine verifier that an Undef
1689   // value isn't a problem.
1690   // The Dead flag is needed as the value in scratch isn't used by any other
1691   // instruction. Kill isn't used as Dead is more precise.
1692   // The implicit flag is here due to the interaction between the other flags
1693   // and the machine verifier.
1694 
1695   // For correctness purpose, a new pseudo is introduced here. We need this
1696   // new pseudo, so that FastRegisterAllocator does not see an ll/sc sequence
1697   // that is spread over >1 basic blocks. A register allocator which
1698   // introduces (or any codegen infact) a store, can violate the expectations
1699   // of the hardware.
1700   //
1701   // An atomic read-modify-write sequence starts with a linked load
1702   // instruction and ends with a store conditional instruction. The atomic
1703   // read-modify-write sequence fails if any of the following conditions
1704   // occur between the execution of ll and sc:
1705   //   * A coherent store is completed by another process or coherent I/O
1706   //     module into the block of synchronizable physical memory containing
1707   //     the word. The size and alignment of the block is
1708   //     implementation-dependent.
1709   //   * A coherent store is executed between an LL and SC sequence on the
1710   //     same processor to the block of synchornizable physical memory
1711   //     containing the word.
1712   //
1713 
1714   Register PtrCopy = RegInfo.createVirtualRegister(RegInfo.getRegClass(Ptr));
1715   Register IncrCopy = RegInfo.createVirtualRegister(RegInfo.getRegClass(Incr));
1716 
1717   BuildMI(*BB, II, DL, TII->get(Mips::COPY), IncrCopy).addReg(Incr);
1718   BuildMI(*BB, II, DL, TII->get(Mips::COPY), PtrCopy).addReg(Ptr);
1719 
1720   MachineInstrBuilder MIB =
1721       BuildMI(*BB, II, DL, TII->get(AtomicOp))
1722           .addReg(OldVal, RegState::Define | RegState::EarlyClobber)
1723           .addReg(PtrCopy)
1724           .addReg(IncrCopy)
1725           .addReg(Scratch, RegState::Define | RegState::EarlyClobber |
1726                                RegState::Implicit | RegState::Dead);
1727   if (NeedsAdditionalReg) {
1728     Register Scratch2 =
1729         RegInfo.createVirtualRegister(RegInfo.getRegClass(OldVal));
1730     MIB.addReg(Scratch2, RegState::Define | RegState::EarlyClobber |
1731                              RegState::Implicit | RegState::Dead);
1732   }
1733 
1734   MI.eraseFromParent();
1735 
1736   return BB;
1737 }
1738 
emitSignExtendToI32InReg(MachineInstr & MI,MachineBasicBlock * BB,unsigned Size,unsigned DstReg,unsigned SrcReg) const1739 MachineBasicBlock *MipsTargetLowering::emitSignExtendToI32InReg(
1740     MachineInstr &MI, MachineBasicBlock *BB, unsigned Size, unsigned DstReg,
1741     unsigned SrcReg) const {
1742   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
1743   const DebugLoc &DL = MI.getDebugLoc();
1744 
1745   if (Subtarget.hasMips32r2() && Size == 1) {
1746     BuildMI(BB, DL, TII->get(Mips::SEB), DstReg).addReg(SrcReg);
1747     return BB;
1748   }
1749 
1750   if (Subtarget.hasMips32r2() && Size == 2) {
1751     BuildMI(BB, DL, TII->get(Mips::SEH), DstReg).addReg(SrcReg);
1752     return BB;
1753   }
1754 
1755   MachineFunction *MF = BB->getParent();
1756   MachineRegisterInfo &RegInfo = MF->getRegInfo();
1757   const TargetRegisterClass *RC = getRegClassFor(MVT::i32);
1758   Register ScrReg = RegInfo.createVirtualRegister(RC);
1759 
1760   assert(Size < 32);
1761   int64_t ShiftImm = 32 - (Size * 8);
1762 
1763   BuildMI(BB, DL, TII->get(Mips::SLL), ScrReg).addReg(SrcReg).addImm(ShiftImm);
1764   BuildMI(BB, DL, TII->get(Mips::SRA), DstReg).addReg(ScrReg).addImm(ShiftImm);
1765 
1766   return BB;
1767 }
1768 
emitAtomicBinaryPartword(MachineInstr & MI,MachineBasicBlock * BB,unsigned Size) const1769 MachineBasicBlock *MipsTargetLowering::emitAtomicBinaryPartword(
1770     MachineInstr &MI, MachineBasicBlock *BB, unsigned Size) const {
1771   assert((Size == 1 || Size == 2) &&
1772          "Unsupported size for EmitAtomicBinaryPartial.");
1773 
1774   MachineFunction *MF = BB->getParent();
1775   MachineRegisterInfo &RegInfo = MF->getRegInfo();
1776   const TargetRegisterClass *RC = getRegClassFor(MVT::i32);
1777   const bool ArePtrs64bit = ABI.ArePtrs64bit();
1778   const TargetRegisterClass *RCp =
1779     getRegClassFor(ArePtrs64bit ? MVT::i64 : MVT::i32);
1780   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
1781   DebugLoc DL = MI.getDebugLoc();
1782 
1783   Register Dest = MI.getOperand(0).getReg();
1784   Register Ptr = MI.getOperand(1).getReg();
1785   Register Incr = MI.getOperand(2).getReg();
1786 
1787   Register AlignedAddr = RegInfo.createVirtualRegister(RCp);
1788   Register ShiftAmt = RegInfo.createVirtualRegister(RC);
1789   Register Mask = RegInfo.createVirtualRegister(RC);
1790   Register Mask2 = RegInfo.createVirtualRegister(RC);
1791   Register Incr2 = RegInfo.createVirtualRegister(RC);
1792   Register MaskLSB2 = RegInfo.createVirtualRegister(RCp);
1793   Register PtrLSB2 = RegInfo.createVirtualRegister(RC);
1794   Register MaskUpper = RegInfo.createVirtualRegister(RC);
1795   Register Scratch = RegInfo.createVirtualRegister(RC);
1796   Register Scratch2 = RegInfo.createVirtualRegister(RC);
1797   Register Scratch3 = RegInfo.createVirtualRegister(RC);
1798 
1799   unsigned AtomicOp = 0;
1800   bool NeedsAdditionalReg = false;
1801   switch (MI.getOpcode()) {
1802   case Mips::ATOMIC_LOAD_NAND_I8:
1803     AtomicOp = Mips::ATOMIC_LOAD_NAND_I8_POSTRA;
1804     break;
1805   case Mips::ATOMIC_LOAD_NAND_I16:
1806     AtomicOp = Mips::ATOMIC_LOAD_NAND_I16_POSTRA;
1807     break;
1808   case Mips::ATOMIC_SWAP_I8:
1809     AtomicOp = Mips::ATOMIC_SWAP_I8_POSTRA;
1810     break;
1811   case Mips::ATOMIC_SWAP_I16:
1812     AtomicOp = Mips::ATOMIC_SWAP_I16_POSTRA;
1813     break;
1814   case Mips::ATOMIC_LOAD_ADD_I8:
1815     AtomicOp = Mips::ATOMIC_LOAD_ADD_I8_POSTRA;
1816     break;
1817   case Mips::ATOMIC_LOAD_ADD_I16:
1818     AtomicOp = Mips::ATOMIC_LOAD_ADD_I16_POSTRA;
1819     break;
1820   case Mips::ATOMIC_LOAD_SUB_I8:
1821     AtomicOp = Mips::ATOMIC_LOAD_SUB_I8_POSTRA;
1822     break;
1823   case Mips::ATOMIC_LOAD_SUB_I16:
1824     AtomicOp = Mips::ATOMIC_LOAD_SUB_I16_POSTRA;
1825     break;
1826   case Mips::ATOMIC_LOAD_AND_I8:
1827     AtomicOp = Mips::ATOMIC_LOAD_AND_I8_POSTRA;
1828     break;
1829   case Mips::ATOMIC_LOAD_AND_I16:
1830     AtomicOp = Mips::ATOMIC_LOAD_AND_I16_POSTRA;
1831     break;
1832   case Mips::ATOMIC_LOAD_OR_I8:
1833     AtomicOp = Mips::ATOMIC_LOAD_OR_I8_POSTRA;
1834     break;
1835   case Mips::ATOMIC_LOAD_OR_I16:
1836     AtomicOp = Mips::ATOMIC_LOAD_OR_I16_POSTRA;
1837     break;
1838   case Mips::ATOMIC_LOAD_XOR_I8:
1839     AtomicOp = Mips::ATOMIC_LOAD_XOR_I8_POSTRA;
1840     break;
1841   case Mips::ATOMIC_LOAD_XOR_I16:
1842     AtomicOp = Mips::ATOMIC_LOAD_XOR_I16_POSTRA;
1843     break;
1844   case Mips::ATOMIC_LOAD_MIN_I8:
1845     AtomicOp = Mips::ATOMIC_LOAD_MIN_I8_POSTRA;
1846     NeedsAdditionalReg = true;
1847     break;
1848   case Mips::ATOMIC_LOAD_MIN_I16:
1849     AtomicOp = Mips::ATOMIC_LOAD_MIN_I16_POSTRA;
1850     NeedsAdditionalReg = true;
1851     break;
1852   case Mips::ATOMIC_LOAD_MAX_I8:
1853     AtomicOp = Mips::ATOMIC_LOAD_MAX_I8_POSTRA;
1854     NeedsAdditionalReg = true;
1855     break;
1856   case Mips::ATOMIC_LOAD_MAX_I16:
1857     AtomicOp = Mips::ATOMIC_LOAD_MAX_I16_POSTRA;
1858     NeedsAdditionalReg = true;
1859     break;
1860   case Mips::ATOMIC_LOAD_UMIN_I8:
1861     AtomicOp = Mips::ATOMIC_LOAD_UMIN_I8_POSTRA;
1862     NeedsAdditionalReg = true;
1863     break;
1864   case Mips::ATOMIC_LOAD_UMIN_I16:
1865     AtomicOp = Mips::ATOMIC_LOAD_UMIN_I16_POSTRA;
1866     NeedsAdditionalReg = true;
1867     break;
1868   case Mips::ATOMIC_LOAD_UMAX_I8:
1869     AtomicOp = Mips::ATOMIC_LOAD_UMAX_I8_POSTRA;
1870     NeedsAdditionalReg = true;
1871     break;
1872   case Mips::ATOMIC_LOAD_UMAX_I16:
1873     AtomicOp = Mips::ATOMIC_LOAD_UMAX_I16_POSTRA;
1874     NeedsAdditionalReg = true;
1875     break;
1876   default:
1877     llvm_unreachable("Unknown subword atomic pseudo for expansion!");
1878   }
1879 
1880   // insert new blocks after the current block
1881   const BasicBlock *LLVM_BB = BB->getBasicBlock();
1882   MachineBasicBlock *exitMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1883   MachineFunction::iterator It = ++BB->getIterator();
1884   MF->insert(It, exitMBB);
1885 
1886   // Transfer the remainder of BB and its successor edges to exitMBB.
1887   exitMBB->splice(exitMBB->begin(), BB,
1888                   std::next(MachineBasicBlock::iterator(MI)), BB->end());
1889   exitMBB->transferSuccessorsAndUpdatePHIs(BB);
1890 
1891   BB->addSuccessor(exitMBB, BranchProbability::getOne());
1892 
1893   //  thisMBB:
1894   //    addiu   masklsb2,$0,-4                # 0xfffffffc
1895   //    and     alignedaddr,ptr,masklsb2
1896   //    andi    ptrlsb2,ptr,3
1897   //    sll     shiftamt,ptrlsb2,3
1898   //    ori     maskupper,$0,255               # 0xff
1899   //    sll     mask,maskupper,shiftamt
1900   //    nor     mask2,$0,mask
1901   //    sll     incr2,incr,shiftamt
1902 
1903   int64_t MaskImm = (Size == 1) ? 255 : 65535;
1904   BuildMI(BB, DL, TII->get(ABI.GetPtrAddiuOp()), MaskLSB2)
1905     .addReg(ABI.GetNullPtr()).addImm(-4);
1906   BuildMI(BB, DL, TII->get(ABI.GetPtrAndOp()), AlignedAddr)
1907     .addReg(Ptr).addReg(MaskLSB2);
1908   BuildMI(BB, DL, TII->get(Mips::ANDi), PtrLSB2)
1909       .addReg(Ptr, 0, ArePtrs64bit ? Mips::sub_32 : 0).addImm(3);
1910   if (Subtarget.isLittle()) {
1911     BuildMI(BB, DL, TII->get(Mips::SLL), ShiftAmt).addReg(PtrLSB2).addImm(3);
1912   } else {
1913     Register Off = RegInfo.createVirtualRegister(RC);
1914     BuildMI(BB, DL, TII->get(Mips::XORi), Off)
1915       .addReg(PtrLSB2).addImm((Size == 1) ? 3 : 2);
1916     BuildMI(BB, DL, TII->get(Mips::SLL), ShiftAmt).addReg(Off).addImm(3);
1917   }
1918   BuildMI(BB, DL, TII->get(Mips::ORi), MaskUpper)
1919     .addReg(Mips::ZERO).addImm(MaskImm);
1920   BuildMI(BB, DL, TII->get(Mips::SLLV), Mask)
1921     .addReg(MaskUpper).addReg(ShiftAmt);
1922   BuildMI(BB, DL, TII->get(Mips::NOR), Mask2).addReg(Mips::ZERO).addReg(Mask);
1923   BuildMI(BB, DL, TII->get(Mips::SLLV), Incr2).addReg(Incr).addReg(ShiftAmt);
1924 
1925 
1926   // The purposes of the flags on the scratch registers is explained in
1927   // emitAtomicBinary. In summary, we need a scratch register which is going to
1928   // be undef, that is unique among registers chosen for the instruction.
1929 
1930   MachineInstrBuilder MIB =
1931       BuildMI(BB, DL, TII->get(AtomicOp))
1932           .addReg(Dest, RegState::Define | RegState::EarlyClobber)
1933           .addReg(AlignedAddr)
1934           .addReg(Incr2)
1935           .addReg(Mask)
1936           .addReg(Mask2)
1937           .addReg(ShiftAmt)
1938           .addReg(Scratch, RegState::EarlyClobber | RegState::Define |
1939                                RegState::Dead | RegState::Implicit)
1940           .addReg(Scratch2, RegState::EarlyClobber | RegState::Define |
1941                                 RegState::Dead | RegState::Implicit)
1942           .addReg(Scratch3, RegState::EarlyClobber | RegState::Define |
1943                                 RegState::Dead | RegState::Implicit);
1944   if (NeedsAdditionalReg) {
1945     Register Scratch4 = RegInfo.createVirtualRegister(RC);
1946     MIB.addReg(Scratch4, RegState::EarlyClobber | RegState::Define |
1947                              RegState::Dead | RegState::Implicit);
1948   }
1949 
1950   MI.eraseFromParent(); // The instruction is gone now.
1951 
1952   return exitMBB;
1953 }
1954 
1955 // Lower atomic compare and swap to a pseudo instruction, taking care to
1956 // define a scratch register for the pseudo instruction's expansion. The
1957 // instruction is expanded after the register allocator as to prevent
1958 // the insertion of stores between the linked load and the store conditional.
1959 
1960 MachineBasicBlock *
emitAtomicCmpSwap(MachineInstr & MI,MachineBasicBlock * BB) const1961 MipsTargetLowering::emitAtomicCmpSwap(MachineInstr &MI,
1962                                       MachineBasicBlock *BB) const {
1963 
1964   assert((MI.getOpcode() == Mips::ATOMIC_CMP_SWAP_I32 ||
1965           MI.getOpcode() == Mips::ATOMIC_CMP_SWAP_I64) &&
1966          "Unsupported atomic pseudo for EmitAtomicCmpSwap.");
1967 
1968   const unsigned Size = MI.getOpcode() == Mips::ATOMIC_CMP_SWAP_I32 ? 4 : 8;
1969 
1970   MachineFunction *MF = BB->getParent();
1971   MachineRegisterInfo &MRI = MF->getRegInfo();
1972   const TargetRegisterClass *RC = getRegClassFor(MVT::getIntegerVT(Size * 8));
1973   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
1974   DebugLoc DL = MI.getDebugLoc();
1975 
1976   unsigned AtomicOp = MI.getOpcode() == Mips::ATOMIC_CMP_SWAP_I32
1977                           ? Mips::ATOMIC_CMP_SWAP_I32_POSTRA
1978                           : Mips::ATOMIC_CMP_SWAP_I64_POSTRA;
1979   Register Dest = MI.getOperand(0).getReg();
1980   Register Ptr = MI.getOperand(1).getReg();
1981   Register OldVal = MI.getOperand(2).getReg();
1982   Register NewVal = MI.getOperand(3).getReg();
1983 
1984   Register Scratch = MRI.createVirtualRegister(RC);
1985   MachineBasicBlock::iterator II(MI);
1986 
1987   // We need to create copies of the various registers and kill them at the
1988   // atomic pseudo. If the copies are not made, when the atomic is expanded
1989   // after fast register allocation, the spills will end up outside of the
1990   // blocks that their values are defined in, causing livein errors.
1991 
1992   Register PtrCopy = MRI.createVirtualRegister(MRI.getRegClass(Ptr));
1993   Register OldValCopy = MRI.createVirtualRegister(MRI.getRegClass(OldVal));
1994   Register NewValCopy = MRI.createVirtualRegister(MRI.getRegClass(NewVal));
1995 
1996   BuildMI(*BB, II, DL, TII->get(Mips::COPY), PtrCopy).addReg(Ptr);
1997   BuildMI(*BB, II, DL, TII->get(Mips::COPY), OldValCopy).addReg(OldVal);
1998   BuildMI(*BB, II, DL, TII->get(Mips::COPY), NewValCopy).addReg(NewVal);
1999 
2000   // The purposes of the flags on the scratch registers is explained in
2001   // emitAtomicBinary. In summary, we need a scratch register which is going to
2002   // be undef, that is unique among registers chosen for the instruction.
2003 
2004   BuildMI(*BB, II, DL, TII->get(AtomicOp))
2005       .addReg(Dest, RegState::Define | RegState::EarlyClobber)
2006       .addReg(PtrCopy, RegState::Kill)
2007       .addReg(OldValCopy, RegState::Kill)
2008       .addReg(NewValCopy, RegState::Kill)
2009       .addReg(Scratch, RegState::EarlyClobber | RegState::Define |
2010                            RegState::Dead | RegState::Implicit);
2011 
2012   MI.eraseFromParent(); // The instruction is gone now.
2013 
2014   return BB;
2015 }
2016 
emitAtomicCmpSwapPartword(MachineInstr & MI,MachineBasicBlock * BB,unsigned Size) const2017 MachineBasicBlock *MipsTargetLowering::emitAtomicCmpSwapPartword(
2018     MachineInstr &MI, MachineBasicBlock *BB, unsigned Size) const {
2019   assert((Size == 1 || Size == 2) &&
2020       "Unsupported size for EmitAtomicCmpSwapPartial.");
2021 
2022   MachineFunction *MF = BB->getParent();
2023   MachineRegisterInfo &RegInfo = MF->getRegInfo();
2024   const TargetRegisterClass *RC = getRegClassFor(MVT::i32);
2025   const bool ArePtrs64bit = ABI.ArePtrs64bit();
2026   const TargetRegisterClass *RCp =
2027     getRegClassFor(ArePtrs64bit ? MVT::i64 : MVT::i32);
2028   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
2029   DebugLoc DL = MI.getDebugLoc();
2030 
2031   Register Dest = MI.getOperand(0).getReg();
2032   Register Ptr = MI.getOperand(1).getReg();
2033   Register CmpVal = MI.getOperand(2).getReg();
2034   Register NewVal = MI.getOperand(3).getReg();
2035 
2036   Register AlignedAddr = RegInfo.createVirtualRegister(RCp);
2037   Register ShiftAmt = RegInfo.createVirtualRegister(RC);
2038   Register Mask = RegInfo.createVirtualRegister(RC);
2039   Register Mask2 = RegInfo.createVirtualRegister(RC);
2040   Register ShiftedCmpVal = RegInfo.createVirtualRegister(RC);
2041   Register ShiftedNewVal = RegInfo.createVirtualRegister(RC);
2042   Register MaskLSB2 = RegInfo.createVirtualRegister(RCp);
2043   Register PtrLSB2 = RegInfo.createVirtualRegister(RC);
2044   Register MaskUpper = RegInfo.createVirtualRegister(RC);
2045   Register MaskedCmpVal = RegInfo.createVirtualRegister(RC);
2046   Register MaskedNewVal = RegInfo.createVirtualRegister(RC);
2047   unsigned AtomicOp = MI.getOpcode() == Mips::ATOMIC_CMP_SWAP_I8
2048                           ? Mips::ATOMIC_CMP_SWAP_I8_POSTRA
2049                           : Mips::ATOMIC_CMP_SWAP_I16_POSTRA;
2050 
2051   // The scratch registers here with the EarlyClobber | Define | Dead | Implicit
2052   // flags are used to coerce the register allocator and the machine verifier to
2053   // accept the usage of these registers.
2054   // The EarlyClobber flag has the semantic properties that the operand it is
2055   // attached to is clobbered before the rest of the inputs are read. Hence it
2056   // must be unique among the operands to the instruction.
2057   // The Define flag is needed to coerce the machine verifier that an Undef
2058   // value isn't a problem.
2059   // The Dead flag is needed as the value in scratch isn't used by any other
2060   // instruction. Kill isn't used as Dead is more precise.
2061   Register Scratch = RegInfo.createVirtualRegister(RC);
2062   Register Scratch2 = RegInfo.createVirtualRegister(RC);
2063 
2064   // insert new blocks after the current block
2065   const BasicBlock *LLVM_BB = BB->getBasicBlock();
2066   MachineBasicBlock *exitMBB = MF->CreateMachineBasicBlock(LLVM_BB);
2067   MachineFunction::iterator It = ++BB->getIterator();
2068   MF->insert(It, exitMBB);
2069 
2070   // Transfer the remainder of BB and its successor edges to exitMBB.
2071   exitMBB->splice(exitMBB->begin(), BB,
2072                   std::next(MachineBasicBlock::iterator(MI)), BB->end());
2073   exitMBB->transferSuccessorsAndUpdatePHIs(BB);
2074 
2075   BB->addSuccessor(exitMBB, BranchProbability::getOne());
2076 
2077   //  thisMBB:
2078   //    addiu   masklsb2,$0,-4                # 0xfffffffc
2079   //    and     alignedaddr,ptr,masklsb2
2080   //    andi    ptrlsb2,ptr,3
2081   //    xori    ptrlsb2,ptrlsb2,3              # Only for BE
2082   //    sll     shiftamt,ptrlsb2,3
2083   //    ori     maskupper,$0,255               # 0xff
2084   //    sll     mask,maskupper,shiftamt
2085   //    nor     mask2,$0,mask
2086   //    andi    maskedcmpval,cmpval,255
2087   //    sll     shiftedcmpval,maskedcmpval,shiftamt
2088   //    andi    maskednewval,newval,255
2089   //    sll     shiftednewval,maskednewval,shiftamt
2090   int64_t MaskImm = (Size == 1) ? 255 : 65535;
2091   BuildMI(BB, DL, TII->get(ArePtrs64bit ? Mips::DADDiu : Mips::ADDiu), MaskLSB2)
2092     .addReg(ABI.GetNullPtr()).addImm(-4);
2093   BuildMI(BB, DL, TII->get(ArePtrs64bit ? Mips::AND64 : Mips::AND), AlignedAddr)
2094     .addReg(Ptr).addReg(MaskLSB2);
2095   BuildMI(BB, DL, TII->get(Mips::ANDi), PtrLSB2)
2096       .addReg(Ptr, 0, ArePtrs64bit ? Mips::sub_32 : 0).addImm(3);
2097   if (Subtarget.isLittle()) {
2098     BuildMI(BB, DL, TII->get(Mips::SLL), ShiftAmt).addReg(PtrLSB2).addImm(3);
2099   } else {
2100     Register Off = RegInfo.createVirtualRegister(RC);
2101     BuildMI(BB, DL, TII->get(Mips::XORi), Off)
2102       .addReg(PtrLSB2).addImm((Size == 1) ? 3 : 2);
2103     BuildMI(BB, DL, TII->get(Mips::SLL), ShiftAmt).addReg(Off).addImm(3);
2104   }
2105   BuildMI(BB, DL, TII->get(Mips::ORi), MaskUpper)
2106     .addReg(Mips::ZERO).addImm(MaskImm);
2107   BuildMI(BB, DL, TII->get(Mips::SLLV), Mask)
2108     .addReg(MaskUpper).addReg(ShiftAmt);
2109   BuildMI(BB, DL, TII->get(Mips::NOR), Mask2).addReg(Mips::ZERO).addReg(Mask);
2110   BuildMI(BB, DL, TII->get(Mips::ANDi), MaskedCmpVal)
2111     .addReg(CmpVal).addImm(MaskImm);
2112   BuildMI(BB, DL, TII->get(Mips::SLLV), ShiftedCmpVal)
2113     .addReg(MaskedCmpVal).addReg(ShiftAmt);
2114   BuildMI(BB, DL, TII->get(Mips::ANDi), MaskedNewVal)
2115     .addReg(NewVal).addImm(MaskImm);
2116   BuildMI(BB, DL, TII->get(Mips::SLLV), ShiftedNewVal)
2117     .addReg(MaskedNewVal).addReg(ShiftAmt);
2118 
2119   // The purposes of the flags on the scratch registers are explained in
2120   // emitAtomicBinary. In summary, we need a scratch register which is going to
2121   // be undef, that is unique among the register chosen for the instruction.
2122 
2123   BuildMI(BB, DL, TII->get(AtomicOp))
2124       .addReg(Dest, RegState::Define | RegState::EarlyClobber)
2125       .addReg(AlignedAddr)
2126       .addReg(Mask)
2127       .addReg(ShiftedCmpVal)
2128       .addReg(Mask2)
2129       .addReg(ShiftedNewVal)
2130       .addReg(ShiftAmt)
2131       .addReg(Scratch, RegState::EarlyClobber | RegState::Define |
2132                            RegState::Dead | RegState::Implicit)
2133       .addReg(Scratch2, RegState::EarlyClobber | RegState::Define |
2134                             RegState::Dead | RegState::Implicit);
2135 
2136   MI.eraseFromParent(); // The instruction is gone now.
2137 
2138   return exitMBB;
2139 }
2140 
lowerREADCYCLECOUNTER(SDValue Op,SelectionDAG & DAG) const2141 SDValue MipsTargetLowering::lowerREADCYCLECOUNTER(SDValue Op,
2142                                                   SelectionDAG &DAG) const {
2143   SmallVector<SDValue, 3> Results;
2144   SDLoc DL(Op);
2145   MachineFunction &MF = DAG.getMachineFunction();
2146   unsigned RdhwrOpc, DestReg;
2147   EVT PtrVT = getPointerTy(DAG.getDataLayout());
2148 
2149   if (PtrVT == MVT::i64) {
2150     RdhwrOpc = Mips::RDHWR64;
2151     DestReg = MF.getRegInfo().createVirtualRegister(getRegClassFor(MVT::i64));
2152     SDNode *Rdhwr = DAG.getMachineNode(RdhwrOpc, DL, MVT::i64, MVT::Glue,
2153                                        DAG.getRegister(Mips::HWR2, MVT::i32),
2154                                        DAG.getTargetConstant(0, DL, MVT::i32));
2155     SDValue Chain = DAG.getCopyToReg(DAG.getEntryNode(), DL, DestReg,
2156                                      SDValue(Rdhwr, 0), SDValue(Rdhwr, 1));
2157     SDValue ResNode =
2158         DAG.getCopyFromReg(Chain, DL, DestReg, MVT::i64, Chain.getValue(1));
2159     Results.push_back(ResNode);
2160     Results.push_back(ResNode.getValue(1));
2161   } else {
2162     RdhwrOpc = Mips::RDHWR;
2163     DestReg = MF.getRegInfo().createVirtualRegister(getRegClassFor(MVT::i32));
2164     SDNode *Rdhwr = DAG.getMachineNode(RdhwrOpc, DL, MVT::i32, MVT::Glue,
2165                                        DAG.getRegister(Mips::HWR2, MVT::i32),
2166                                        DAG.getTargetConstant(0, DL, MVT::i32));
2167     SDValue Chain = DAG.getCopyToReg(DAG.getEntryNode(), DL, DestReg,
2168                                      SDValue(Rdhwr, 0), SDValue(Rdhwr, 1));
2169     SDValue ResNode =
2170         DAG.getCopyFromReg(Chain, DL, DestReg, MVT::i32, Chain.getValue(1));
2171     Results.push_back(DAG.getNode(ISD::BUILD_PAIR, DL, MVT::i64, ResNode,
2172                                   DAG.getConstant(0, DL, MVT::i32)));
2173     Results.push_back(ResNode.getValue(1));
2174   }
2175 
2176   return DAG.getMergeValues(Results, DL);
2177 }
2178 
lowerBRCOND(SDValue Op,SelectionDAG & DAG) const2179 SDValue MipsTargetLowering::lowerBRCOND(SDValue Op, SelectionDAG &DAG) const {
2180   // The first operand is the chain, the second is the condition, the third is
2181   // the block to branch to if the condition is true.
2182   SDValue Chain = Op.getOperand(0);
2183   SDValue Dest = Op.getOperand(2);
2184   SDLoc DL(Op);
2185 
2186   assert(!Subtarget.hasMips32r6() && !Subtarget.hasMips64r6());
2187   SDValue CondRes = createFPCmp(DAG, Op.getOperand(1));
2188 
2189   // Return if flag is not set by a floating point comparison.
2190   if (CondRes.getOpcode() != MipsISD::FPCmp)
2191     return Op;
2192 
2193   SDValue CCNode  = CondRes.getOperand(2);
2194   Mips::CondCode CC = (Mips::CondCode)CCNode->getAsZExtVal();
2195   unsigned Opc = invertFPCondCodeUser(CC) ? Mips::BRANCH_F : Mips::BRANCH_T;
2196   SDValue BrCode = DAG.getConstant(Opc, DL, MVT::i32);
2197   SDValue FCC0 = DAG.getRegister(Mips::FCC0, MVT::i32);
2198   return DAG.getNode(MipsISD::FPBrcond, DL, Op.getValueType(), Chain, BrCode,
2199                      FCC0, Dest, CondRes);
2200 }
2201 
2202 SDValue MipsTargetLowering::
lowerSELECT(SDValue Op,SelectionDAG & DAG) const2203 lowerSELECT(SDValue Op, SelectionDAG &DAG) const
2204 {
2205   assert(!Subtarget.hasMips32r6() && !Subtarget.hasMips64r6());
2206   SDValue Cond = createFPCmp(DAG, Op.getOperand(0));
2207 
2208   // Return if flag is not set by a floating point comparison.
2209   if (Cond.getOpcode() != MipsISD::FPCmp)
2210     return Op;
2211 
2212   return createCMovFP(DAG, Cond, Op.getOperand(1), Op.getOperand(2),
2213                       SDLoc(Op));
2214 }
2215 
lowerSETCC(SDValue Op,SelectionDAG & DAG) const2216 SDValue MipsTargetLowering::lowerSETCC(SDValue Op, SelectionDAG &DAG) const {
2217   assert(!Subtarget.hasMips32r6() && !Subtarget.hasMips64r6());
2218   SDValue Cond = createFPCmp(DAG, Op);
2219 
2220   assert(Cond.getOpcode() == MipsISD::FPCmp &&
2221          "Floating point operand expected.");
2222 
2223   SDLoc DL(Op);
2224   SDValue True  = DAG.getConstant(1, DL, MVT::i32);
2225   SDValue False = DAG.getConstant(0, DL, MVT::i32);
2226 
2227   return createCMovFP(DAG, Cond, True, False, DL);
2228 }
2229 
lowerGlobalAddress(SDValue Op,SelectionDAG & DAG) const2230 SDValue MipsTargetLowering::lowerGlobalAddress(SDValue Op,
2231                                                SelectionDAG &DAG) const {
2232   EVT Ty = Op.getValueType();
2233   GlobalAddressSDNode *N = cast<GlobalAddressSDNode>(Op);
2234   const GlobalValue *GV = N->getGlobal();
2235 
2236   if (GV->hasDLLImportStorageClass()) {
2237     assert(Subtarget.isTargetWindows() &&
2238            "Windows is the only supported COFF target");
2239     return getDllimportVariable(
2240         N, SDLoc(N), Ty, DAG, DAG.getEntryNode(),
2241         MachinePointerInfo::getGOT(DAG.getMachineFunction()));
2242   }
2243 
2244   if (!isPositionIndependent()) {
2245     const MipsTargetObjectFile *TLOF =
2246         static_cast<const MipsTargetObjectFile *>(
2247             getTargetMachine().getObjFileLowering());
2248     const GlobalObject *GO = GV->getAliaseeObject();
2249     if (GO && TLOF->IsGlobalInSmallSection(GO, getTargetMachine()))
2250       // %gp_rel relocation
2251       return getAddrGPRel(N, SDLoc(N), Ty, DAG, ABI.IsN64());
2252 
2253                                 // %hi/%lo relocation
2254     return Subtarget.hasSym32() ? getAddrNonPIC(N, SDLoc(N), Ty, DAG)
2255                                 // %highest/%higher/%hi/%lo relocation
2256                                 : getAddrNonPICSym64(N, SDLoc(N), Ty, DAG);
2257   }
2258 
2259   // Every other architecture would use shouldAssumeDSOLocal in here, but
2260   // mips is special.
2261   // * In PIC code mips requires got loads even for local statics!
2262   // * To save on got entries, for local statics the got entry contains the
2263   //   page and an additional add instruction takes care of the low bits.
2264   // * It is legal to access a hidden symbol with a non hidden undefined,
2265   //   so one cannot guarantee that all access to a hidden symbol will know
2266   //   it is hidden.
2267   // * Mips linkers don't support creating a page and a full got entry for
2268   //   the same symbol.
2269   // * Given all that, we have to use a full got entry for hidden symbols :-(
2270   if (GV->hasLocalLinkage())
2271     return getAddrLocal(N, SDLoc(N), Ty, DAG, ABI.IsN32() || ABI.IsN64());
2272 
2273   if (Subtarget.useXGOT())
2274     return getAddrGlobalLargeGOT(
2275         N, SDLoc(N), Ty, DAG, MipsII::MO_GOT_HI16, MipsII::MO_GOT_LO16,
2276         DAG.getEntryNode(),
2277         MachinePointerInfo::getGOT(DAG.getMachineFunction()));
2278 
2279   return getAddrGlobal(
2280       N, SDLoc(N), Ty, DAG,
2281       (ABI.IsN32() || ABI.IsN64()) ? MipsII::MO_GOT_DISP : MipsII::MO_GOT,
2282       DAG.getEntryNode(), MachinePointerInfo::getGOT(DAG.getMachineFunction()));
2283 }
2284 
lowerBlockAddress(SDValue Op,SelectionDAG & DAG) const2285 SDValue MipsTargetLowering::lowerBlockAddress(SDValue Op,
2286                                               SelectionDAG &DAG) const {
2287   BlockAddressSDNode *N = cast<BlockAddressSDNode>(Op);
2288   EVT Ty = Op.getValueType();
2289 
2290   if (!isPositionIndependent())
2291     return Subtarget.hasSym32() ? getAddrNonPIC(N, SDLoc(N), Ty, DAG)
2292                                 : getAddrNonPICSym64(N, SDLoc(N), Ty, DAG);
2293 
2294   return getAddrLocal(N, SDLoc(N), Ty, DAG, ABI.IsN32() || ABI.IsN64());
2295 }
2296 
2297 SDValue MipsTargetLowering::
lowerGlobalTLSAddress(SDValue Op,SelectionDAG & DAG) const2298 lowerGlobalTLSAddress(SDValue Op, SelectionDAG &DAG) const
2299 {
2300   // If the relocation model is PIC, use the General Dynamic TLS Model or
2301   // Local Dynamic TLS model, otherwise use the Initial Exec or
2302   // Local Exec TLS Model.
2303 
2304   GlobalAddressSDNode *GA = cast<GlobalAddressSDNode>(Op);
2305   if (DAG.getTarget().useEmulatedTLS())
2306     return LowerToTLSEmulatedModel(GA, DAG);
2307 
2308   SDLoc DL(GA);
2309   const GlobalValue *GV = GA->getGlobal();
2310   EVT PtrVT = getPointerTy(DAG.getDataLayout());
2311 
2312   TLSModel::Model model = getTargetMachine().getTLSModel(GV);
2313 
2314   if (model == TLSModel::GeneralDynamic || model == TLSModel::LocalDynamic) {
2315     // General Dynamic and Local Dynamic TLS Model.
2316     unsigned Flag = (model == TLSModel::LocalDynamic) ? MipsII::MO_TLSLDM
2317                                                       : MipsII::MO_TLSGD;
2318 
2319     SDValue TGA = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0, Flag);
2320     SDValue Argument = DAG.getNode(MipsISD::Wrapper, DL, PtrVT,
2321                                    getGlobalReg(DAG, PtrVT), TGA);
2322     unsigned PtrSize = PtrVT.getSizeInBits();
2323     IntegerType *PtrTy = Type::getIntNTy(*DAG.getContext(), PtrSize);
2324 
2325     SDValue TlsGetAddr = DAG.getExternalSymbol("__tls_get_addr", PtrVT);
2326 
2327     ArgListTy Args;
2328     ArgListEntry Entry;
2329     Entry.Node = Argument;
2330     Entry.Ty = PtrTy;
2331     Args.push_back(Entry);
2332 
2333     TargetLowering::CallLoweringInfo CLI(DAG);
2334     CLI.setDebugLoc(DL)
2335         .setChain(DAG.getEntryNode())
2336         .setLibCallee(CallingConv::C, PtrTy, TlsGetAddr, std::move(Args));
2337     std::pair<SDValue, SDValue> CallResult = LowerCallTo(CLI);
2338 
2339     SDValue Ret = CallResult.first;
2340 
2341     if (model != TLSModel::LocalDynamic)
2342       return Ret;
2343 
2344     SDValue TGAHi = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0,
2345                                                MipsII::MO_DTPREL_HI);
2346     SDValue Hi = DAG.getNode(MipsISD::TlsHi, DL, PtrVT, TGAHi);
2347     SDValue TGALo = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0,
2348                                                MipsII::MO_DTPREL_LO);
2349     SDValue Lo = DAG.getNode(MipsISD::Lo, DL, PtrVT, TGALo);
2350     SDValue Add = DAG.getNode(ISD::ADD, DL, PtrVT, Hi, Ret);
2351     return DAG.getNode(ISD::ADD, DL, PtrVT, Add, Lo);
2352   }
2353 
2354   SDValue Offset;
2355   if (model == TLSModel::InitialExec) {
2356     // Initial Exec TLS Model
2357     SDValue TGA = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0,
2358                                              MipsII::MO_GOTTPREL);
2359     TGA = DAG.getNode(MipsISD::Wrapper, DL, PtrVT, getGlobalReg(DAG, PtrVT),
2360                       TGA);
2361     Offset =
2362         DAG.getLoad(PtrVT, DL, DAG.getEntryNode(), TGA, MachinePointerInfo());
2363   } else {
2364     // Local Exec TLS Model
2365     assert(model == TLSModel::LocalExec);
2366     SDValue TGAHi = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0,
2367                                                MipsII::MO_TPREL_HI);
2368     SDValue TGALo = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0,
2369                                                MipsII::MO_TPREL_LO);
2370     SDValue Hi = DAG.getNode(MipsISD::TlsHi, DL, PtrVT, TGAHi);
2371     SDValue Lo = DAG.getNode(MipsISD::Lo, DL, PtrVT, TGALo);
2372     Offset = DAG.getNode(ISD::ADD, DL, PtrVT, Hi, Lo);
2373   }
2374 
2375   SDValue ThreadPointer = DAG.getNode(MipsISD::ThreadPointer, DL, PtrVT);
2376   return DAG.getNode(ISD::ADD, DL, PtrVT, ThreadPointer, Offset);
2377 }
2378 
2379 SDValue MipsTargetLowering::
lowerJumpTable(SDValue Op,SelectionDAG & DAG) const2380 lowerJumpTable(SDValue Op, SelectionDAG &DAG) const
2381 {
2382   JumpTableSDNode *N = cast<JumpTableSDNode>(Op);
2383   EVT Ty = Op.getValueType();
2384 
2385   if (!isPositionIndependent())
2386     return Subtarget.hasSym32() ? getAddrNonPIC(N, SDLoc(N), Ty, DAG)
2387                                 : getAddrNonPICSym64(N, SDLoc(N), Ty, DAG);
2388 
2389   return getAddrLocal(N, SDLoc(N), Ty, DAG, ABI.IsN32() || ABI.IsN64());
2390 }
2391 
2392 SDValue MipsTargetLowering::
lowerConstantPool(SDValue Op,SelectionDAG & DAG) const2393 lowerConstantPool(SDValue Op, SelectionDAG &DAG) const
2394 {
2395   ConstantPoolSDNode *N = cast<ConstantPoolSDNode>(Op);
2396   EVT Ty = Op.getValueType();
2397 
2398   if (!isPositionIndependent()) {
2399     const MipsTargetObjectFile *TLOF =
2400         static_cast<const MipsTargetObjectFile *>(
2401             getTargetMachine().getObjFileLowering());
2402 
2403     if (TLOF->IsConstantInSmallSection(DAG.getDataLayout(), N->getConstVal(),
2404                                        getTargetMachine()))
2405       // %gp_rel relocation
2406       return getAddrGPRel(N, SDLoc(N), Ty, DAG, ABI.IsN64());
2407 
2408     return Subtarget.hasSym32() ? getAddrNonPIC(N, SDLoc(N), Ty, DAG)
2409                                 : getAddrNonPICSym64(N, SDLoc(N), Ty, DAG);
2410   }
2411 
2412  return getAddrLocal(N, SDLoc(N), Ty, DAG, ABI.IsN32() || ABI.IsN64());
2413 }
2414 
lowerVASTART(SDValue Op,SelectionDAG & DAG) const2415 SDValue MipsTargetLowering::lowerVASTART(SDValue Op, SelectionDAG &DAG) const {
2416   MachineFunction &MF = DAG.getMachineFunction();
2417   MipsFunctionInfo *FuncInfo = MF.getInfo<MipsFunctionInfo>();
2418 
2419   SDLoc DL(Op);
2420   SDValue FI = DAG.getFrameIndex(FuncInfo->getVarArgsFrameIndex(),
2421                                  getPointerTy(MF.getDataLayout()));
2422 
2423   // vastart just stores the address of the VarArgsFrameIndex slot into the
2424   // memory location argument.
2425   const Value *SV = cast<SrcValueSDNode>(Op.getOperand(2))->getValue();
2426   return DAG.getStore(Op.getOperand(0), DL, FI, Op.getOperand(1),
2427                       MachinePointerInfo(SV));
2428 }
2429 
lowerVAARG(SDValue Op,SelectionDAG & DAG) const2430 SDValue MipsTargetLowering::lowerVAARG(SDValue Op, SelectionDAG &DAG) const {
2431   SDNode *Node = Op.getNode();
2432   EVT VT = Node->getValueType(0);
2433   SDValue Chain = Node->getOperand(0);
2434   SDValue VAListPtr = Node->getOperand(1);
2435   const Align Align =
2436       llvm::MaybeAlign(Node->getConstantOperandVal(3)).valueOrOne();
2437   const Value *SV = cast<SrcValueSDNode>(Node->getOperand(2))->getValue();
2438   SDLoc DL(Node);
2439   unsigned ArgSlotSizeInBytes = (ABI.IsN32() || ABI.IsN64()) ? 8 : 4;
2440 
2441   SDValue VAListLoad = DAG.getLoad(getPointerTy(DAG.getDataLayout()), DL, Chain,
2442                                    VAListPtr, MachinePointerInfo(SV));
2443   SDValue VAList = VAListLoad;
2444 
2445   // Re-align the pointer if necessary.
2446   // It should only ever be necessary for 64-bit types on O32 since the minimum
2447   // argument alignment is the same as the maximum type alignment for N32/N64.
2448   //
2449   // FIXME: We currently align too often. The code generator doesn't notice
2450   //        when the pointer is still aligned from the last va_arg (or pair of
2451   //        va_args for the i64 on O32 case).
2452   if (Align > getMinStackArgumentAlignment()) {
2453     VAList = DAG.getNode(
2454         ISD::ADD, DL, VAList.getValueType(), VAList,
2455         DAG.getConstant(Align.value() - 1, DL, VAList.getValueType()));
2456 
2457     VAList = DAG.getNode(ISD::AND, DL, VAList.getValueType(), VAList,
2458                          DAG.getSignedConstant(-(int64_t)Align.value(), DL,
2459                                                VAList.getValueType()));
2460   }
2461 
2462   // Increment the pointer, VAList, to the next vaarg.
2463   auto &TD = DAG.getDataLayout();
2464   unsigned ArgSizeInBytes =
2465       TD.getTypeAllocSize(VT.getTypeForEVT(*DAG.getContext()));
2466   SDValue Tmp3 =
2467       DAG.getNode(ISD::ADD, DL, VAList.getValueType(), VAList,
2468                   DAG.getConstant(alignTo(ArgSizeInBytes, ArgSlotSizeInBytes),
2469                                   DL, VAList.getValueType()));
2470   // Store the incremented VAList to the legalized pointer
2471   Chain = DAG.getStore(VAListLoad.getValue(1), DL, Tmp3, VAListPtr,
2472                        MachinePointerInfo(SV));
2473 
2474   // In big-endian mode we must adjust the pointer when the load size is smaller
2475   // than the argument slot size. We must also reduce the known alignment to
2476   // match. For example in the N64 ABI, we must add 4 bytes to the offset to get
2477   // the correct half of the slot, and reduce the alignment from 8 (slot
2478   // alignment) down to 4 (type alignment).
2479   if (!Subtarget.isLittle() && ArgSizeInBytes < ArgSlotSizeInBytes) {
2480     unsigned Adjustment = ArgSlotSizeInBytes - ArgSizeInBytes;
2481     VAList = DAG.getNode(ISD::ADD, DL, VAListPtr.getValueType(), VAList,
2482                          DAG.getIntPtrConstant(Adjustment, DL));
2483   }
2484   // Load the actual argument out of the pointer VAList
2485   return DAG.getLoad(VT, DL, Chain, VAList, MachinePointerInfo());
2486 }
2487 
lowerFCOPYSIGN32(SDValue Op,SelectionDAG & DAG,bool HasExtractInsert)2488 static SDValue lowerFCOPYSIGN32(SDValue Op, SelectionDAG &DAG,
2489                                 bool HasExtractInsert) {
2490   EVT TyX = Op.getOperand(0).getValueType();
2491   EVT TyY = Op.getOperand(1).getValueType();
2492   SDLoc DL(Op);
2493   SDValue Const1 = DAG.getConstant(1, DL, MVT::i32);
2494   SDValue Const31 = DAG.getConstant(31, DL, MVT::i32);
2495   SDValue Res;
2496 
2497   // If operand is of type f64, extract the upper 32-bit. Otherwise, bitcast it
2498   // to i32.
2499   SDValue X = (TyX == MVT::f32) ?
2500     DAG.getNode(ISD::BITCAST, DL, MVT::i32, Op.getOperand(0)) :
2501     DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32, Op.getOperand(0),
2502                 Const1);
2503   SDValue Y = (TyY == MVT::f32) ?
2504     DAG.getNode(ISD::BITCAST, DL, MVT::i32, Op.getOperand(1)) :
2505     DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32, Op.getOperand(1),
2506                 Const1);
2507 
2508   if (HasExtractInsert) {
2509     // ext  E, Y, 31, 1  ; extract bit31 of Y
2510     // ins  X, E, 31, 1  ; insert extracted bit at bit31 of X
2511     SDValue E = DAG.getNode(MipsISD::Ext, DL, MVT::i32, Y, Const31, Const1);
2512     Res = DAG.getNode(MipsISD::Ins, DL, MVT::i32, E, Const31, Const1, X);
2513   } else {
2514     // sll SllX, X, 1
2515     // srl SrlX, SllX, 1
2516     // srl SrlY, Y, 31
2517     // sll SllY, SrlX, 31
2518     // or  Or, SrlX, SllY
2519     SDValue SllX = DAG.getNode(ISD::SHL, DL, MVT::i32, X, Const1);
2520     SDValue SrlX = DAG.getNode(ISD::SRL, DL, MVT::i32, SllX, Const1);
2521     SDValue SrlY = DAG.getNode(ISD::SRL, DL, MVT::i32, Y, Const31);
2522     SDValue SllY = DAG.getNode(ISD::SHL, DL, MVT::i32, SrlY, Const31);
2523     Res = DAG.getNode(ISD::OR, DL, MVT::i32, SrlX, SllY);
2524   }
2525 
2526   if (TyX == MVT::f32)
2527     return DAG.getNode(ISD::BITCAST, DL, Op.getOperand(0).getValueType(), Res);
2528 
2529   SDValue LowX = DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32,
2530                              Op.getOperand(0),
2531                              DAG.getConstant(0, DL, MVT::i32));
2532   return DAG.getNode(MipsISD::BuildPairF64, DL, MVT::f64, LowX, Res);
2533 }
2534 
lowerFCOPYSIGN64(SDValue Op,SelectionDAG & DAG,bool HasExtractInsert)2535 static SDValue lowerFCOPYSIGN64(SDValue Op, SelectionDAG &DAG,
2536                                 bool HasExtractInsert) {
2537   unsigned WidthX = Op.getOperand(0).getValueSizeInBits();
2538   unsigned WidthY = Op.getOperand(1).getValueSizeInBits();
2539   EVT TyX = MVT::getIntegerVT(WidthX), TyY = MVT::getIntegerVT(WidthY);
2540   SDLoc DL(Op);
2541   SDValue Const1 = DAG.getConstant(1, DL, MVT::i32);
2542 
2543   // Bitcast to integer nodes.
2544   SDValue X = DAG.getNode(ISD::BITCAST, DL, TyX, Op.getOperand(0));
2545   SDValue Y = DAG.getNode(ISD::BITCAST, DL, TyY, Op.getOperand(1));
2546 
2547   if (HasExtractInsert) {
2548     // ext  E, Y, width(Y) - 1, 1  ; extract bit width(Y)-1 of Y
2549     // ins  X, E, width(X) - 1, 1  ; insert extracted bit at bit width(X)-1 of X
2550     SDValue E = DAG.getNode(MipsISD::Ext, DL, TyY, Y,
2551                             DAG.getConstant(WidthY - 1, DL, MVT::i32), Const1);
2552 
2553     if (WidthX > WidthY)
2554       E = DAG.getNode(ISD::ZERO_EXTEND, DL, TyX, E);
2555     else if (WidthY > WidthX)
2556       E = DAG.getNode(ISD::TRUNCATE, DL, TyX, E);
2557 
2558     SDValue I = DAG.getNode(MipsISD::Ins, DL, TyX, E,
2559                             DAG.getConstant(WidthX - 1, DL, MVT::i32), Const1,
2560                             X);
2561     return DAG.getNode(ISD::BITCAST, DL, Op.getOperand(0).getValueType(), I);
2562   }
2563 
2564   // (d)sll SllX, X, 1
2565   // (d)srl SrlX, SllX, 1
2566   // (d)srl SrlY, Y, width(Y)-1
2567   // (d)sll SllY, SrlX, width(Y)-1
2568   // or     Or, SrlX, SllY
2569   SDValue SllX = DAG.getNode(ISD::SHL, DL, TyX, X, Const1);
2570   SDValue SrlX = DAG.getNode(ISD::SRL, DL, TyX, SllX, Const1);
2571   SDValue SrlY = DAG.getNode(ISD::SRL, DL, TyY, Y,
2572                              DAG.getConstant(WidthY - 1, DL, MVT::i32));
2573 
2574   if (WidthX > WidthY)
2575     SrlY = DAG.getNode(ISD::ZERO_EXTEND, DL, TyX, SrlY);
2576   else if (WidthY > WidthX)
2577     SrlY = DAG.getNode(ISD::TRUNCATE, DL, TyX, SrlY);
2578 
2579   SDValue SllY = DAG.getNode(ISD::SHL, DL, TyX, SrlY,
2580                              DAG.getConstant(WidthX - 1, DL, MVT::i32));
2581   SDValue Or = DAG.getNode(ISD::OR, DL, TyX, SrlX, SllY);
2582   return DAG.getNode(ISD::BITCAST, DL, Op.getOperand(0).getValueType(), Or);
2583 }
2584 
2585 SDValue
lowerFCOPYSIGN(SDValue Op,SelectionDAG & DAG) const2586 MipsTargetLowering::lowerFCOPYSIGN(SDValue Op, SelectionDAG &DAG) const {
2587   if (Subtarget.isGP64bit())
2588     return lowerFCOPYSIGN64(Op, DAG, Subtarget.hasExtractInsert());
2589 
2590   return lowerFCOPYSIGN32(Op, DAG, Subtarget.hasExtractInsert());
2591 }
2592 
lowerFABS32(SDValue Op,SelectionDAG & DAG,bool HasExtractInsert) const2593 SDValue MipsTargetLowering::lowerFABS32(SDValue Op, SelectionDAG &DAG,
2594                                         bool HasExtractInsert) const {
2595   SDLoc DL(Op);
2596   SDValue Res, Const1 = DAG.getConstant(1, DL, MVT::i32);
2597 
2598   if (DAG.getTarget().Options.NoNaNsFPMath || Subtarget.inAbs2008Mode())
2599     return DAG.getNode(MipsISD::FAbs, DL, Op.getValueType(), Op.getOperand(0));
2600 
2601   // If operand is of type f64, extract the upper 32-bit. Otherwise, bitcast it
2602   // to i32.
2603   SDValue X = (Op.getValueType() == MVT::f32)
2604                   ? DAG.getNode(ISD::BITCAST, DL, MVT::i32, Op.getOperand(0))
2605                   : DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32,
2606                                 Op.getOperand(0), Const1);
2607 
2608   // Clear MSB.
2609   if (HasExtractInsert)
2610     Res = DAG.getNode(MipsISD::Ins, DL, MVT::i32,
2611                       DAG.getRegister(Mips::ZERO, MVT::i32),
2612                       DAG.getConstant(31, DL, MVT::i32), Const1, X);
2613   else {
2614     // TODO: Provide DAG patterns which transform (and x, cst)
2615     // back to a (shl (srl x (clz cst)) (clz cst)) sequence.
2616     SDValue SllX = DAG.getNode(ISD::SHL, DL, MVT::i32, X, Const1);
2617     Res = DAG.getNode(ISD::SRL, DL, MVT::i32, SllX, Const1);
2618   }
2619 
2620   if (Op.getValueType() == MVT::f32)
2621     return DAG.getNode(ISD::BITCAST, DL, MVT::f32, Res);
2622 
2623   // FIXME: For mips32r2, the sequence of (BuildPairF64 (ins (ExtractElementF64
2624   // Op 1), $zero, 31 1) (ExtractElementF64 Op 0)) and the Op has one use, we
2625   // should be able to drop the usage of mfc1/mtc1 and rewrite the register in
2626   // place.
2627   SDValue LowX =
2628       DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32, Op.getOperand(0),
2629                   DAG.getConstant(0, DL, MVT::i32));
2630   return DAG.getNode(MipsISD::BuildPairF64, DL, MVT::f64, LowX, Res);
2631 }
2632 
lowerFABS64(SDValue Op,SelectionDAG & DAG,bool HasExtractInsert) const2633 SDValue MipsTargetLowering::lowerFABS64(SDValue Op, SelectionDAG &DAG,
2634                                         bool HasExtractInsert) const {
2635   SDLoc DL(Op);
2636   SDValue Res, Const1 = DAG.getConstant(1, DL, MVT::i32);
2637 
2638   if (DAG.getTarget().Options.NoNaNsFPMath || Subtarget.inAbs2008Mode())
2639     return DAG.getNode(MipsISD::FAbs, DL, Op.getValueType(), Op.getOperand(0));
2640 
2641   // Bitcast to integer node.
2642   SDValue X = DAG.getNode(ISD::BITCAST, DL, MVT::i64, Op.getOperand(0));
2643 
2644   // Clear MSB.
2645   if (HasExtractInsert)
2646     Res = DAG.getNode(MipsISD::Ins, DL, MVT::i64,
2647                       DAG.getRegister(Mips::ZERO_64, MVT::i64),
2648                       DAG.getConstant(63, DL, MVT::i32), Const1, X);
2649   else {
2650     SDValue SllX = DAG.getNode(ISD::SHL, DL, MVT::i64, X, Const1);
2651     Res = DAG.getNode(ISD::SRL, DL, MVT::i64, SllX, Const1);
2652   }
2653 
2654   return DAG.getNode(ISD::BITCAST, DL, MVT::f64, Res);
2655 }
2656 
lowerFABS(SDValue Op,SelectionDAG & DAG) const2657 SDValue MipsTargetLowering::lowerFABS(SDValue Op, SelectionDAG &DAG) const {
2658   if ((ABI.IsN32() || ABI.IsN64()) && (Op.getValueType() == MVT::f64))
2659     return lowerFABS64(Op, DAG, Subtarget.hasExtractInsert());
2660 
2661   return lowerFABS32(Op, DAG, Subtarget.hasExtractInsert());
2662 }
2663 
lowerFCANONICALIZE(SDValue Op,SelectionDAG & DAG) const2664 SDValue MipsTargetLowering::lowerFCANONICALIZE(SDValue Op,
2665                                                SelectionDAG &DAG) const {
2666   SDLoc DL(Op);
2667   EVT VT = Op.getValueType();
2668   SDValue Operand = Op.getOperand(0);
2669   SDNodeFlags Flags = Op->getFlags();
2670 
2671   if (Flags.hasNoNaNs() || DAG.isKnownNeverNaN(Operand))
2672     return Operand;
2673 
2674   SDValue Quiet = DAG.getNode(ISD::FADD, DL, VT, Operand, Operand);
2675   return DAG.getSelectCC(DL, Operand, Operand, Quiet, Operand, ISD::SETUO);
2676 }
2677 
2678 SDValue MipsTargetLowering::
lowerFRAMEADDR(SDValue Op,SelectionDAG & DAG) const2679 lowerFRAMEADDR(SDValue Op, SelectionDAG &DAG) const {
2680   // check the depth
2681   if (Op.getConstantOperandVal(0) != 0) {
2682     DAG.getContext()->emitError(
2683         "return address can be determined only for current frame");
2684     return SDValue();
2685   }
2686 
2687   MachineFrameInfo &MFI = DAG.getMachineFunction().getFrameInfo();
2688   MFI.setFrameAddressIsTaken(true);
2689   EVT VT = Op.getValueType();
2690   SDLoc DL(Op);
2691   SDValue FrameAddr = DAG.getCopyFromReg(
2692       DAG.getEntryNode(), DL, ABI.IsN64() ? Mips::FP_64 : Mips::FP, VT);
2693   return FrameAddr;
2694 }
2695 
lowerRETURNADDR(SDValue Op,SelectionDAG & DAG) const2696 SDValue MipsTargetLowering::lowerRETURNADDR(SDValue Op,
2697                                             SelectionDAG &DAG) const {
2698   // check the depth
2699   if (Op.getConstantOperandVal(0) != 0) {
2700     DAG.getContext()->emitError(
2701         "return address can be determined only for current frame");
2702     return SDValue();
2703   }
2704 
2705   MachineFunction &MF = DAG.getMachineFunction();
2706   MachineFrameInfo &MFI = MF.getFrameInfo();
2707   MVT VT = Op.getSimpleValueType();
2708   unsigned RA = ABI.IsN64() ? Mips::RA_64 : Mips::RA;
2709   MFI.setReturnAddressIsTaken(true);
2710 
2711   // Return RA, which contains the return address. Mark it an implicit live-in.
2712   Register Reg = MF.addLiveIn(RA, getRegClassFor(VT));
2713   return DAG.getCopyFromReg(DAG.getEntryNode(), SDLoc(Op), Reg, VT);
2714 }
2715 
2716 // An EH_RETURN is the result of lowering llvm.eh.return which in turn is
2717 // generated from __builtin_eh_return (offset, handler)
2718 // The effect of this is to adjust the stack pointer by "offset"
2719 // and then branch to "handler".
lowerEH_RETURN(SDValue Op,SelectionDAG & DAG) const2720 SDValue MipsTargetLowering::lowerEH_RETURN(SDValue Op, SelectionDAG &DAG)
2721                                                                      const {
2722   MachineFunction &MF = DAG.getMachineFunction();
2723   MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
2724 
2725   MipsFI->setCallsEhReturn();
2726   SDValue Chain     = Op.getOperand(0);
2727   SDValue Offset    = Op.getOperand(1);
2728   SDValue Handler   = Op.getOperand(2);
2729   SDLoc DL(Op);
2730   EVT Ty = ABI.IsN64() ? MVT::i64 : MVT::i32;
2731 
2732   // Store stack offset in V1, store jump target in V0. Glue CopyToReg and
2733   // EH_RETURN nodes, so that instructions are emitted back-to-back.
2734   unsigned OffsetReg = ABI.IsN64() ? Mips::V1_64 : Mips::V1;
2735   unsigned AddrReg = ABI.IsN64() ? Mips::V0_64 : Mips::V0;
2736   Chain = DAG.getCopyToReg(Chain, DL, OffsetReg, Offset, SDValue());
2737   Chain = DAG.getCopyToReg(Chain, DL, AddrReg, Handler, Chain.getValue(1));
2738   return DAG.getNode(MipsISD::EH_RETURN, DL, MVT::Other, Chain,
2739                      DAG.getRegister(OffsetReg, Ty),
2740                      DAG.getRegister(AddrReg, getPointerTy(MF.getDataLayout())),
2741                      Chain.getValue(1));
2742 }
2743 
lowerATOMIC_FENCE(SDValue Op,SelectionDAG & DAG) const2744 SDValue MipsTargetLowering::lowerATOMIC_FENCE(SDValue Op,
2745                                               SelectionDAG &DAG) const {
2746   // FIXME: Need pseudo-fence for 'singlethread' fences
2747   // FIXME: Set SType for weaker fences where supported/appropriate.
2748   unsigned SType = 0;
2749   SDLoc DL(Op);
2750   return DAG.getNode(MipsISD::Sync, DL, MVT::Other, Op.getOperand(0),
2751                      DAG.getConstant(SType, DL, MVT::i32));
2752 }
2753 
lowerShiftLeftParts(SDValue Op,SelectionDAG & DAG) const2754 SDValue MipsTargetLowering::lowerShiftLeftParts(SDValue Op,
2755                                                 SelectionDAG &DAG) const {
2756   SDLoc DL(Op);
2757   MVT VT = Subtarget.isGP64bit() ? MVT::i64 : MVT::i32;
2758 
2759   SDValue Lo = Op.getOperand(0), Hi = Op.getOperand(1);
2760   SDValue Shamt = Op.getOperand(2);
2761   // if shamt < (VT.bits):
2762   //  lo = (shl lo, shamt)
2763   //  hi = (or (shl hi, shamt) (srl (srl lo, 1), (xor shamt, (VT.bits-1))))
2764   // else:
2765   //  lo = 0
2766   //  hi = (shl lo, shamt[4:0])
2767   SDValue Not =
2768       DAG.getNode(ISD::XOR, DL, MVT::i32, Shamt,
2769                   DAG.getConstant(VT.getSizeInBits() - 1, DL, MVT::i32));
2770   SDValue ShiftRight1Lo = DAG.getNode(ISD::SRL, DL, VT, Lo,
2771                                       DAG.getConstant(1, DL, VT));
2772   SDValue ShiftRightLo = DAG.getNode(ISD::SRL, DL, VT, ShiftRight1Lo, Not);
2773   SDValue ShiftLeftHi = DAG.getNode(ISD::SHL, DL, VT, Hi, Shamt);
2774   SDValue Or = DAG.getNode(ISD::OR, DL, VT, ShiftLeftHi, ShiftRightLo);
2775   SDValue ShiftLeftLo = DAG.getNode(ISD::SHL, DL, VT, Lo, Shamt);
2776   SDValue Cond = DAG.getNode(ISD::AND, DL, MVT::i32, Shamt,
2777                              DAG.getConstant(VT.getSizeInBits(), DL, MVT::i32));
2778   Lo = DAG.getNode(ISD::SELECT, DL, VT, Cond,
2779                    DAG.getConstant(0, DL, VT), ShiftLeftLo);
2780   Hi = DAG.getNode(ISD::SELECT, DL, VT, Cond, ShiftLeftLo, Or);
2781 
2782   SDValue Ops[2] = {Lo, Hi};
2783   return DAG.getMergeValues(Ops, DL);
2784 }
2785 
lowerShiftRightParts(SDValue Op,SelectionDAG & DAG,bool IsSRA) const2786 SDValue MipsTargetLowering::lowerShiftRightParts(SDValue Op, SelectionDAG &DAG,
2787                                                  bool IsSRA) const {
2788   SDLoc DL(Op);
2789   SDValue Lo = Op.getOperand(0), Hi = Op.getOperand(1);
2790   SDValue Shamt = Op.getOperand(2);
2791   MVT VT = Subtarget.isGP64bit() ? MVT::i64 : MVT::i32;
2792 
2793   // if shamt < (VT.bits):
2794   //  lo = (or (shl (shl hi, 1), (xor shamt, (VT.bits-1))) (srl lo, shamt))
2795   //  if isSRA:
2796   //    hi = (sra hi, shamt)
2797   //  else:
2798   //    hi = (srl hi, shamt)
2799   // else:
2800   //  if isSRA:
2801   //   lo = (sra hi, shamt[4:0])
2802   //   hi = (sra hi, 31)
2803   //  else:
2804   //   lo = (srl hi, shamt[4:0])
2805   //   hi = 0
2806   SDValue Not =
2807       DAG.getNode(ISD::XOR, DL, MVT::i32, Shamt,
2808                   DAG.getConstant(VT.getSizeInBits() - 1, DL, MVT::i32));
2809   SDValue ShiftLeft1Hi = DAG.getNode(ISD::SHL, DL, VT, Hi,
2810                                      DAG.getConstant(1, DL, VT));
2811   SDValue ShiftLeftHi = DAG.getNode(ISD::SHL, DL, VT, ShiftLeft1Hi, Not);
2812   SDValue ShiftRightLo = DAG.getNode(ISD::SRL, DL, VT, Lo, Shamt);
2813   SDValue Or = DAG.getNode(ISD::OR, DL, VT, ShiftLeftHi, ShiftRightLo);
2814   SDValue ShiftRightHi = DAG.getNode(IsSRA ? ISD::SRA : ISD::SRL,
2815                                      DL, VT, Hi, Shamt);
2816   SDValue Cond = DAG.getNode(ISD::AND, DL, MVT::i32, Shamt,
2817                              DAG.getConstant(VT.getSizeInBits(), DL, MVT::i32));
2818   SDValue Ext = DAG.getNode(ISD::SRA, DL, VT, Hi,
2819                             DAG.getConstant(VT.getSizeInBits() - 1, DL, VT));
2820 
2821   if (!(Subtarget.hasMips4() || Subtarget.hasMips32())) {
2822     SDVTList VTList = DAG.getVTList(VT, VT);
2823     return DAG.getNode(Subtarget.isGP64bit() ? MipsISD::DOUBLE_SELECT_I64
2824                                              : MipsISD::DOUBLE_SELECT_I,
2825                        DL, VTList, Cond, ShiftRightHi,
2826                        IsSRA ? Ext : DAG.getConstant(0, DL, VT), Or,
2827                        ShiftRightHi);
2828   }
2829 
2830   Lo = DAG.getNode(ISD::SELECT, DL, VT, Cond, ShiftRightHi, Or);
2831   Hi = DAG.getNode(ISD::SELECT, DL, VT, Cond,
2832                    IsSRA ? Ext : DAG.getConstant(0, DL, VT), ShiftRightHi);
2833 
2834   SDValue Ops[2] = {Lo, Hi};
2835   return DAG.getMergeValues(Ops, DL);
2836 }
2837 
createLoadLR(unsigned Opc,SelectionDAG & DAG,LoadSDNode * LD,SDValue Chain,SDValue Src,unsigned Offset)2838 static SDValue createLoadLR(unsigned Opc, SelectionDAG &DAG, LoadSDNode *LD,
2839                             SDValue Chain, SDValue Src, unsigned Offset) {
2840   SDValue Ptr = LD->getBasePtr();
2841   EVT VT = LD->getValueType(0), MemVT = LD->getMemoryVT();
2842   EVT BasePtrVT = Ptr.getValueType();
2843   SDLoc DL(LD);
2844   SDVTList VTList = DAG.getVTList(VT, MVT::Other);
2845 
2846   if (Offset)
2847     Ptr = DAG.getNode(ISD::ADD, DL, BasePtrVT, Ptr,
2848                       DAG.getConstant(Offset, DL, BasePtrVT));
2849 
2850   SDValue Ops[] = { Chain, Ptr, Src };
2851   return DAG.getMemIntrinsicNode(Opc, DL, VTList, Ops, MemVT,
2852                                  LD->getMemOperand());
2853 }
2854 
2855 // Expand an unaligned 32 or 64-bit integer load node.
lowerLOAD(SDValue Op,SelectionDAG & DAG) const2856 SDValue MipsTargetLowering::lowerLOAD(SDValue Op, SelectionDAG &DAG) const {
2857   LoadSDNode *LD = cast<LoadSDNode>(Op);
2858   EVT MemVT = LD->getMemoryVT();
2859 
2860   if (Subtarget.systemSupportsUnalignedAccess())
2861     return Op;
2862 
2863   // Return if load is aligned or if MemVT is neither i32 nor i64.
2864   if ((LD->getAlign().value() >= (MemVT.getSizeInBits() / 8)) ||
2865       ((MemVT != MVT::i32) && (MemVT != MVT::i64)))
2866     return SDValue();
2867 
2868   bool IsLittle = Subtarget.isLittle();
2869   EVT VT = Op.getValueType();
2870   ISD::LoadExtType ExtType = LD->getExtensionType();
2871   SDValue Chain = LD->getChain(), Undef = DAG.getUNDEF(VT);
2872 
2873   assert((VT == MVT::i32) || (VT == MVT::i64));
2874 
2875   // Expand
2876   //  (set dst, (i64 (load baseptr)))
2877   // to
2878   //  (set tmp, (ldl (add baseptr, 7), undef))
2879   //  (set dst, (ldr baseptr, tmp))
2880   if ((VT == MVT::i64) && (ExtType == ISD::NON_EXTLOAD)) {
2881     SDValue LDL = createLoadLR(MipsISD::LDL, DAG, LD, Chain, Undef,
2882                                IsLittle ? 7 : 0);
2883     return createLoadLR(MipsISD::LDR, DAG, LD, LDL.getValue(1), LDL,
2884                         IsLittle ? 0 : 7);
2885   }
2886 
2887   SDValue LWL = createLoadLR(MipsISD::LWL, DAG, LD, Chain, Undef,
2888                              IsLittle ? 3 : 0);
2889   SDValue LWR = createLoadLR(MipsISD::LWR, DAG, LD, LWL.getValue(1), LWL,
2890                              IsLittle ? 0 : 3);
2891 
2892   // Expand
2893   //  (set dst, (i32 (load baseptr))) or
2894   //  (set dst, (i64 (sextload baseptr))) or
2895   //  (set dst, (i64 (extload baseptr)))
2896   // to
2897   //  (set tmp, (lwl (add baseptr, 3), undef))
2898   //  (set dst, (lwr baseptr, tmp))
2899   if ((VT == MVT::i32) || (ExtType == ISD::SEXTLOAD) ||
2900       (ExtType == ISD::EXTLOAD))
2901     return LWR;
2902 
2903   assert((VT == MVT::i64) && (ExtType == ISD::ZEXTLOAD));
2904 
2905   // Expand
2906   //  (set dst, (i64 (zextload baseptr)))
2907   // to
2908   //  (set tmp0, (lwl (add baseptr, 3), undef))
2909   //  (set tmp1, (lwr baseptr, tmp0))
2910   //  (set tmp2, (shl tmp1, 32))
2911   //  (set dst, (srl tmp2, 32))
2912   SDLoc DL(LD);
2913   SDValue Const32 = DAG.getConstant(32, DL, MVT::i32);
2914   SDValue SLL = DAG.getNode(ISD::SHL, DL, MVT::i64, LWR, Const32);
2915   SDValue SRL = DAG.getNode(ISD::SRL, DL, MVT::i64, SLL, Const32);
2916   SDValue Ops[] = { SRL, LWR.getValue(1) };
2917   return DAG.getMergeValues(Ops, DL);
2918 }
2919 
createStoreLR(unsigned Opc,SelectionDAG & DAG,StoreSDNode * SD,SDValue Chain,unsigned Offset)2920 static SDValue createStoreLR(unsigned Opc, SelectionDAG &DAG, StoreSDNode *SD,
2921                              SDValue Chain, unsigned Offset) {
2922   SDValue Ptr = SD->getBasePtr(), Value = SD->getValue();
2923   EVT MemVT = SD->getMemoryVT(), BasePtrVT = Ptr.getValueType();
2924   SDLoc DL(SD);
2925   SDVTList VTList = DAG.getVTList(MVT::Other);
2926 
2927   if (Offset)
2928     Ptr = DAG.getNode(ISD::ADD, DL, BasePtrVT, Ptr,
2929                       DAG.getConstant(Offset, DL, BasePtrVT));
2930 
2931   SDValue Ops[] = { Chain, Value, Ptr };
2932   return DAG.getMemIntrinsicNode(Opc, DL, VTList, Ops, MemVT,
2933                                  SD->getMemOperand());
2934 }
2935 
2936 // Expand an unaligned 32 or 64-bit integer store node.
lowerUnalignedIntStore(StoreSDNode * SD,SelectionDAG & DAG,bool IsLittle)2937 static SDValue lowerUnalignedIntStore(StoreSDNode *SD, SelectionDAG &DAG,
2938                                       bool IsLittle) {
2939   SDValue Value = SD->getValue(), Chain = SD->getChain();
2940   EVT VT = Value.getValueType();
2941 
2942   // Expand
2943   //  (store val, baseptr) or
2944   //  (truncstore val, baseptr)
2945   // to
2946   //  (swl val, (add baseptr, 3))
2947   //  (swr val, baseptr)
2948   if ((VT == MVT::i32) || SD->isTruncatingStore()) {
2949     SDValue SWL = createStoreLR(MipsISD::SWL, DAG, SD, Chain,
2950                                 IsLittle ? 3 : 0);
2951     return createStoreLR(MipsISD::SWR, DAG, SD, SWL, IsLittle ? 0 : 3);
2952   }
2953 
2954   assert(VT == MVT::i64);
2955 
2956   // Expand
2957   //  (store val, baseptr)
2958   // to
2959   //  (sdl val, (add baseptr, 7))
2960   //  (sdr val, baseptr)
2961   SDValue SDL = createStoreLR(MipsISD::SDL, DAG, SD, Chain, IsLittle ? 7 : 0);
2962   return createStoreLR(MipsISD::SDR, DAG, SD, SDL, IsLittle ? 0 : 7);
2963 }
2964 
2965 // Lower (store (fp_to_sint $fp) $ptr) to (store (TruncIntFP $fp), $ptr).
lowerFP_TO_SINT_STORE(StoreSDNode * SD,SelectionDAG & DAG,bool SingleFloat)2966 static SDValue lowerFP_TO_SINT_STORE(StoreSDNode *SD, SelectionDAG &DAG,
2967                                      bool SingleFloat) {
2968   SDValue Val = SD->getValue();
2969 
2970   if (Val.getOpcode() != ISD::FP_TO_SINT ||
2971       (Val.getValueSizeInBits() > 32 && SingleFloat))
2972     return SDValue();
2973 
2974   EVT FPTy = EVT::getFloatingPointVT(Val.getValueSizeInBits());
2975   SDValue Tr = DAG.getNode(MipsISD::TruncIntFP, SDLoc(Val), FPTy,
2976                            Val.getOperand(0));
2977   return DAG.getStore(SD->getChain(), SDLoc(SD), Tr, SD->getBasePtr(),
2978                       SD->getPointerInfo(), SD->getAlign(),
2979                       SD->getMemOperand()->getFlags());
2980 }
2981 
lowerSTORE(SDValue Op,SelectionDAG & DAG) const2982 SDValue MipsTargetLowering::lowerSTORE(SDValue Op, SelectionDAG &DAG) const {
2983   StoreSDNode *SD = cast<StoreSDNode>(Op);
2984   EVT MemVT = SD->getMemoryVT();
2985 
2986   // Lower unaligned integer stores.
2987   if (!Subtarget.systemSupportsUnalignedAccess() &&
2988       (SD->getAlign().value() < (MemVT.getSizeInBits() / 8)) &&
2989       ((MemVT == MVT::i32) || (MemVT == MVT::i64)))
2990     return lowerUnalignedIntStore(SD, DAG, Subtarget.isLittle());
2991 
2992   return lowerFP_TO_SINT_STORE(SD, DAG, Subtarget.isSingleFloat());
2993 }
2994 
lowerEH_DWARF_CFA(SDValue Op,SelectionDAG & DAG) const2995 SDValue MipsTargetLowering::lowerEH_DWARF_CFA(SDValue Op,
2996                                               SelectionDAG &DAG) const {
2997 
2998   // Return a fixed StackObject with offset 0 which points to the old stack
2999   // pointer.
3000   MachineFrameInfo &MFI = DAG.getMachineFunction().getFrameInfo();
3001   EVT ValTy = Op->getValueType(0);
3002   int FI = MFI.CreateFixedObject(Op.getValueSizeInBits() / 8, 0, false);
3003   return DAG.getFrameIndex(FI, ValTy);
3004 }
3005 
lowerFP_TO_SINT(SDValue Op,SelectionDAG & DAG) const3006 SDValue MipsTargetLowering::lowerFP_TO_SINT(SDValue Op,
3007                                             SelectionDAG &DAG) const {
3008   if (Op.getValueSizeInBits() > 32 && Subtarget.isSingleFloat())
3009     return SDValue();
3010 
3011   EVT FPTy = EVT::getFloatingPointVT(Op.getValueSizeInBits());
3012   SDValue Trunc = DAG.getNode(MipsISD::TruncIntFP, SDLoc(Op), FPTy,
3013                               Op.getOperand(0));
3014   return DAG.getNode(ISD::BITCAST, SDLoc(Op), Op.getValueType(), Trunc);
3015 }
3016 
3017 //===----------------------------------------------------------------------===//
3018 //                      Calling Convention Implementation
3019 //===----------------------------------------------------------------------===//
3020 
3021 //===----------------------------------------------------------------------===//
3022 // TODO: Implement a generic logic using tblgen that can support this.
3023 // Mips O32 ABI rules:
3024 // ---
3025 // i32 - Passed in A0, A1, A2, A3 and stack
3026 // f32 - Only passed in f32 registers if no int reg has been used yet to hold
3027 //       an argument. Otherwise, passed in A1, A2, A3 and stack.
3028 // f64 - Only passed in two aliased f32 registers if no int reg has been used
3029 //       yet to hold an argument. Otherwise, use A2, A3 and stack. If A1 is
3030 //       not used, it must be shadowed. If only A3 is available, shadow it and
3031 //       go to stack.
3032 // vXiX - Received as scalarized i32s, passed in A0 - A3 and the stack.
3033 // vXf32 - Passed in either a pair of registers {A0, A1}, {A2, A3} or {A0 - A3}
3034 //         with the remainder spilled to the stack.
3035 // vXf64 - Passed in either {A0, A1, A2, A3} or {A2, A3} and in both cases
3036 //         spilling the remainder to the stack.
3037 //
3038 //  For vararg functions, all arguments are passed in A0, A1, A2, A3 and stack.
3039 //===----------------------------------------------------------------------===//
3040 
CC_MipsO32(unsigned ValNo,MVT ValVT,MVT LocVT,CCValAssign::LocInfo LocInfo,ISD::ArgFlagsTy ArgFlags,CCState & State,ArrayRef<MCPhysReg> F64Regs)3041 static bool CC_MipsO32(unsigned ValNo, MVT ValVT, MVT LocVT,
3042                        CCValAssign::LocInfo LocInfo, ISD::ArgFlagsTy ArgFlags,
3043                        CCState &State, ArrayRef<MCPhysReg> F64Regs) {
3044   const MipsSubtarget &Subtarget = static_cast<const MipsSubtarget &>(
3045       State.getMachineFunction().getSubtarget());
3046 
3047   static const MCPhysReg IntRegs[] = { Mips::A0, Mips::A1, Mips::A2, Mips::A3 };
3048 
3049   const MipsCCState * MipsState = static_cast<MipsCCState *>(&State);
3050 
3051   static const MCPhysReg F32Regs[] = { Mips::F12, Mips::F14 };
3052 
3053   static const MCPhysReg FloatVectorIntRegs[] = { Mips::A0, Mips::A2 };
3054 
3055   // Do not process byval args here.
3056   if (ArgFlags.isByVal())
3057     return true;
3058 
3059   // Promote i8 and i16
3060   if (ArgFlags.isInReg() && !Subtarget.isLittle()) {
3061     if (LocVT == MVT::i8 || LocVT == MVT::i16 || LocVT == MVT::i32) {
3062       LocVT = MVT::i32;
3063       if (ArgFlags.isSExt())
3064         LocInfo = CCValAssign::SExtUpper;
3065       else if (ArgFlags.isZExt())
3066         LocInfo = CCValAssign::ZExtUpper;
3067       else
3068         LocInfo = CCValAssign::AExtUpper;
3069     }
3070   }
3071 
3072   // Promote i8 and i16
3073   if (LocVT == MVT::i8 || LocVT == MVT::i16) {
3074     LocVT = MVT::i32;
3075     if (ArgFlags.isSExt())
3076       LocInfo = CCValAssign::SExt;
3077     else if (ArgFlags.isZExt())
3078       LocInfo = CCValAssign::ZExt;
3079     else
3080       LocInfo = CCValAssign::AExt;
3081   }
3082 
3083   unsigned Reg;
3084 
3085   // f32 and f64 are allocated in A0, A1, A2, A3 when either of the following
3086   // is true: function is vararg, argument is 3rd or higher, there is previous
3087   // argument which is not f32 or f64.
3088   bool AllocateFloatsInIntReg = State.isVarArg() || ValNo > 1 ||
3089                                 State.getFirstUnallocated(F32Regs) != ValNo;
3090   Align OrigAlign = ArgFlags.getNonZeroOrigAlign();
3091   bool isI64 = (ValVT == MVT::i32 && OrigAlign == Align(8));
3092   bool isVectorFloat = MipsState->WasOriginalArgVectorFloat(ValNo);
3093 
3094   // The MIPS vector ABI for floats passes them in a pair of registers
3095   if (ValVT == MVT::i32 && isVectorFloat) {
3096     // This is the start of an vector that was scalarized into an unknown number
3097     // of components. It doesn't matter how many there are. Allocate one of the
3098     // notional 8 byte aligned registers which map onto the argument stack, and
3099     // shadow the register lost to alignment requirements.
3100     if (ArgFlags.isSplit()) {
3101       Reg = State.AllocateReg(FloatVectorIntRegs);
3102       if (Reg == Mips::A2)
3103         State.AllocateReg(Mips::A1);
3104       else if (Reg == 0)
3105         State.AllocateReg(Mips::A3);
3106     } else {
3107       // If we're an intermediate component of the split, we can just attempt to
3108       // allocate a register directly.
3109       Reg = State.AllocateReg(IntRegs);
3110     }
3111   } else if (ValVT == MVT::i32 ||
3112              (ValVT == MVT::f32 && AllocateFloatsInIntReg)) {
3113     Reg = State.AllocateReg(IntRegs);
3114     // If this is the first part of an i64 arg,
3115     // the allocated register must be either A0 or A2.
3116     if (isI64 && (Reg == Mips::A1 || Reg == Mips::A3))
3117       Reg = State.AllocateReg(IntRegs);
3118     LocVT = MVT::i32;
3119   } else if (ValVT == MVT::f64 && AllocateFloatsInIntReg) {
3120     // Allocate int register and shadow next int register. If first
3121     // available register is Mips::A1 or Mips::A3, shadow it too.
3122     Reg = State.AllocateReg(IntRegs);
3123     if (Reg == Mips::A1 || Reg == Mips::A3)
3124       Reg = State.AllocateReg(IntRegs);
3125 
3126     if (Reg) {
3127       LocVT = MVT::i32;
3128 
3129       State.addLoc(
3130           CCValAssign::getCustomReg(ValNo, ValVT, Reg, LocVT, LocInfo));
3131       MCRegister HiReg = State.AllocateReg(IntRegs);
3132       assert(HiReg);
3133       State.addLoc(
3134           CCValAssign::getCustomReg(ValNo, ValVT, HiReg, LocVT, LocInfo));
3135       return false;
3136     }
3137   } else if (ValVT.isFloatingPoint() && !AllocateFloatsInIntReg) {
3138     // we are guaranteed to find an available float register
3139     if (ValVT == MVT::f32) {
3140       Reg = State.AllocateReg(F32Regs);
3141       // Shadow int register
3142       State.AllocateReg(IntRegs);
3143     } else {
3144       Reg = State.AllocateReg(F64Regs);
3145       // Shadow int registers
3146       MCRegister Reg2 = State.AllocateReg(IntRegs);
3147       if (Reg2 == Mips::A1 || Reg2 == Mips::A3)
3148         State.AllocateReg(IntRegs);
3149       State.AllocateReg(IntRegs);
3150     }
3151   } else
3152     llvm_unreachable("Cannot handle this ValVT.");
3153 
3154   if (!Reg) {
3155     unsigned Offset = State.AllocateStack(ValVT.getStoreSize(), OrigAlign);
3156     State.addLoc(CCValAssign::getMem(ValNo, ValVT, Offset, LocVT, LocInfo));
3157   } else
3158     State.addLoc(CCValAssign::getReg(ValNo, ValVT, Reg, LocVT, LocInfo));
3159 
3160   return false;
3161 }
3162 
CC_MipsO32_FP32(unsigned ValNo,MVT ValVT,MVT LocVT,CCValAssign::LocInfo LocInfo,ISD::ArgFlagsTy ArgFlags,CCState & State)3163 static bool CC_MipsO32_FP32(unsigned ValNo, MVT ValVT,
3164                             MVT LocVT, CCValAssign::LocInfo LocInfo,
3165                             ISD::ArgFlagsTy ArgFlags, CCState &State) {
3166   static const MCPhysReg F64Regs[] = { Mips::D6, Mips::D7 };
3167 
3168   return CC_MipsO32(ValNo, ValVT, LocVT, LocInfo, ArgFlags, State, F64Regs);
3169 }
3170 
CC_MipsO32_FP64(unsigned ValNo,MVT ValVT,MVT LocVT,CCValAssign::LocInfo LocInfo,ISD::ArgFlagsTy ArgFlags,CCState & State)3171 static bool CC_MipsO32_FP64(unsigned ValNo, MVT ValVT,
3172                             MVT LocVT, CCValAssign::LocInfo LocInfo,
3173                             ISD::ArgFlagsTy ArgFlags, CCState &State) {
3174   static const MCPhysReg F64Regs[] = { Mips::D12_64, Mips::D14_64 };
3175 
3176   return CC_MipsO32(ValNo, ValVT, LocVT, LocInfo, ArgFlags, State, F64Regs);
3177 }
3178 
3179 static bool CC_MipsO32(unsigned ValNo, MVT ValVT, MVT LocVT,
3180                        CCValAssign::LocInfo LocInfo, ISD::ArgFlagsTy ArgFlags,
3181                        CCState &State) LLVM_ATTRIBUTE_UNUSED;
3182 
3183 #include "MipsGenCallingConv.inc"
3184 
CCAssignFnForCall() const3185  CCAssignFn *MipsTargetLowering::CCAssignFnForCall() const{
3186    return CC_Mips_FixedArg;
3187  }
3188 
CCAssignFnForReturn() const3189  CCAssignFn *MipsTargetLowering::CCAssignFnForReturn() const{
3190    return RetCC_Mips;
3191  }
3192 //===----------------------------------------------------------------------===//
3193 //                  Call Calling Convention Implementation
3194 //===----------------------------------------------------------------------===//
3195 
passArgOnStack(SDValue StackPtr,unsigned Offset,SDValue Chain,SDValue Arg,const SDLoc & DL,bool IsTailCall,SelectionDAG & DAG) const3196 SDValue MipsTargetLowering::passArgOnStack(SDValue StackPtr, unsigned Offset,
3197                                            SDValue Chain, SDValue Arg,
3198                                            const SDLoc &DL, bool IsTailCall,
3199                                            SelectionDAG &DAG) const {
3200   if (!IsTailCall) {
3201     SDValue PtrOff =
3202         DAG.getNode(ISD::ADD, DL, getPointerTy(DAG.getDataLayout()), StackPtr,
3203                     DAG.getIntPtrConstant(Offset, DL));
3204     return DAG.getStore(Chain, DL, Arg, PtrOff, MachinePointerInfo());
3205   }
3206 
3207   MachineFrameInfo &MFI = DAG.getMachineFunction().getFrameInfo();
3208   int FI = MFI.CreateFixedObject(Arg.getValueSizeInBits() / 8, Offset, false);
3209   SDValue FIN = DAG.getFrameIndex(FI, getPointerTy(DAG.getDataLayout()));
3210   return DAG.getStore(Chain, DL, Arg, FIN, MachinePointerInfo(), MaybeAlign(),
3211                       MachineMemOperand::MOVolatile);
3212 }
3213 
3214 void MipsTargetLowering::
getOpndList(SmallVectorImpl<SDValue> & Ops,std::deque<std::pair<unsigned,SDValue>> & RegsToPass,bool IsPICCall,bool GlobalOrExternal,bool InternalLinkage,bool IsCallReloc,CallLoweringInfo & CLI,SDValue Callee,SDValue Chain) const3215 getOpndList(SmallVectorImpl<SDValue> &Ops,
3216             std::deque<std::pair<unsigned, SDValue>> &RegsToPass,
3217             bool IsPICCall, bool GlobalOrExternal, bool InternalLinkage,
3218             bool IsCallReloc, CallLoweringInfo &CLI, SDValue Callee,
3219             SDValue Chain) const {
3220   // Insert node "GP copy globalreg" before call to function.
3221   //
3222   // R_MIPS_CALL* operators (emitted when non-internal functions are called
3223   // in PIC mode) allow symbols to be resolved via lazy binding.
3224   // The lazy binding stub requires GP to point to the GOT.
3225   // Note that we don't need GP to point to the GOT for indirect calls
3226   // (when R_MIPS_CALL* is not used for the call) because Mips linker generates
3227   // lazy binding stub for a function only when R_MIPS_CALL* are the only relocs
3228   // used for the function (that is, Mips linker doesn't generate lazy binding
3229   // stub for a function whose address is taken in the program).
3230   if (IsPICCall && !InternalLinkage && IsCallReloc) {
3231     unsigned GPReg = ABI.IsN64() ? Mips::GP_64 : Mips::GP;
3232     EVT Ty = ABI.IsN64() ? MVT::i64 : MVT::i32;
3233     RegsToPass.push_back(std::make_pair(GPReg, getGlobalReg(CLI.DAG, Ty)));
3234   }
3235 
3236   // Build a sequence of copy-to-reg nodes chained together with token
3237   // chain and flag operands which copy the outgoing args into registers.
3238   // The InGlue in necessary since all emitted instructions must be
3239   // stuck together.
3240   SDValue InGlue;
3241 
3242   for (auto &R : RegsToPass) {
3243     Chain = CLI.DAG.getCopyToReg(Chain, CLI.DL, R.first, R.second, InGlue);
3244     InGlue = Chain.getValue(1);
3245   }
3246 
3247   // Add argument registers to the end of the list so that they are
3248   // known live into the call.
3249   for (auto &R : RegsToPass)
3250     Ops.push_back(CLI.DAG.getRegister(R.first, R.second.getValueType()));
3251 
3252   // Add a register mask operand representing the call-preserved registers.
3253   const TargetRegisterInfo *TRI = Subtarget.getRegisterInfo();
3254   const uint32_t *Mask =
3255       TRI->getCallPreservedMask(CLI.DAG.getMachineFunction(), CLI.CallConv);
3256   assert(Mask && "Missing call preserved mask for calling convention");
3257   if (Subtarget.inMips16HardFloat()) {
3258     if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(CLI.Callee)) {
3259       StringRef Sym = G->getGlobal()->getName();
3260       Function *F = G->getGlobal()->getParent()->getFunction(Sym);
3261       if (F && F->hasFnAttribute("__Mips16RetHelper")) {
3262         Mask = MipsRegisterInfo::getMips16RetHelperMask();
3263       }
3264     }
3265   }
3266   Ops.push_back(CLI.DAG.getRegisterMask(Mask));
3267 
3268   if (InGlue.getNode())
3269     Ops.push_back(InGlue);
3270 }
3271 
AdjustInstrPostInstrSelection(MachineInstr & MI,SDNode * Node) const3272 void MipsTargetLowering::AdjustInstrPostInstrSelection(MachineInstr &MI,
3273                                                        SDNode *Node) const {
3274   switch (MI.getOpcode()) {
3275     default:
3276       return;
3277     case Mips::JALR:
3278     case Mips::JALRPseudo:
3279     case Mips::JALR64:
3280     case Mips::JALR64Pseudo:
3281     case Mips::JALR16_MM:
3282     case Mips::JALRC16_MMR6:
3283     case Mips::TAILCALLREG:
3284     case Mips::TAILCALLREG64:
3285     case Mips::TAILCALLR6REG:
3286     case Mips::TAILCALL64R6REG:
3287     case Mips::TAILCALLREG_MM:
3288     case Mips::TAILCALLREG_MMR6: {
3289       if (!EmitJalrReloc ||
3290           Subtarget.inMips16Mode() ||
3291           !isPositionIndependent() ||
3292           Node->getNumOperands() < 1 ||
3293           Node->getOperand(0).getNumOperands() < 2) {
3294         return;
3295       }
3296       // We are after the callee address, set by LowerCall().
3297       // If added to MI, asm printer will emit .reloc R_MIPS_JALR for the
3298       // symbol.
3299       const SDValue TargetAddr = Node->getOperand(0).getOperand(1);
3300       StringRef Sym;
3301       if (const GlobalAddressSDNode *G =
3302               dyn_cast_or_null<const GlobalAddressSDNode>(TargetAddr)) {
3303         // We must not emit the R_MIPS_JALR relocation against data symbols
3304         // since this will cause run-time crashes if the linker replaces the
3305         // call instruction with a relative branch to the data symbol.
3306         if (!isa<Function>(G->getGlobal())) {
3307           LLVM_DEBUG(dbgs() << "Not adding R_MIPS_JALR against data symbol "
3308                             << G->getGlobal()->getName() << "\n");
3309           return;
3310         }
3311         Sym = G->getGlobal()->getName();
3312       }
3313       else if (const ExternalSymbolSDNode *ES =
3314                    dyn_cast_or_null<const ExternalSymbolSDNode>(TargetAddr)) {
3315         Sym = ES->getSymbol();
3316       }
3317 
3318       if (Sym.empty())
3319         return;
3320 
3321       MachineFunction *MF = MI.getParent()->getParent();
3322       MCSymbol *S = MF->getContext().getOrCreateSymbol(Sym);
3323       LLVM_DEBUG(dbgs() << "Adding R_MIPS_JALR against " << Sym << "\n");
3324       MI.addOperand(MachineOperand::CreateMCSymbol(S, MipsII::MO_JALR));
3325     }
3326   }
3327 }
3328 
3329 /// LowerCall - functions arguments are copied from virtual regs to
3330 /// (physical regs)/(stack frame), CALLSEQ_START and CALLSEQ_END are emitted.
3331 SDValue
LowerCall(TargetLowering::CallLoweringInfo & CLI,SmallVectorImpl<SDValue> & InVals) const3332 MipsTargetLowering::LowerCall(TargetLowering::CallLoweringInfo &CLI,
3333                               SmallVectorImpl<SDValue> &InVals) const {
3334   SelectionDAG &DAG                     = CLI.DAG;
3335   SDLoc DL                              = CLI.DL;
3336   SmallVectorImpl<ISD::OutputArg> &Outs = CLI.Outs;
3337   SmallVectorImpl<SDValue> &OutVals     = CLI.OutVals;
3338   SmallVectorImpl<ISD::InputArg> &Ins   = CLI.Ins;
3339   SDValue Chain                         = CLI.Chain;
3340   SDValue Callee                        = CLI.Callee;
3341   bool &IsTailCall                      = CLI.IsTailCall;
3342   CallingConv::ID CallConv              = CLI.CallConv;
3343   bool IsVarArg                         = CLI.IsVarArg;
3344 
3345   MachineFunction &MF = DAG.getMachineFunction();
3346   MachineFrameInfo &MFI = MF.getFrameInfo();
3347   const TargetFrameLowering *TFL = Subtarget.getFrameLowering();
3348   MipsFunctionInfo *FuncInfo = MF.getInfo<MipsFunctionInfo>();
3349   bool IsPIC = isPositionIndependent();
3350 
3351   // Analyze operands of the call, assigning locations to each operand.
3352   SmallVector<CCValAssign, 16> ArgLocs;
3353   MipsCCState CCInfo(
3354       CallConv, IsVarArg, DAG.getMachineFunction(), ArgLocs, *DAG.getContext(),
3355       MipsCCState::getSpecialCallingConvForCallee(Callee.getNode(), Subtarget));
3356 
3357   const ExternalSymbolSDNode *ES =
3358       dyn_cast_or_null<const ExternalSymbolSDNode>(Callee.getNode());
3359 
3360   // There is one case where CALLSEQ_START..CALLSEQ_END can be nested, which
3361   // is during the lowering of a call with a byval argument which produces
3362   // a call to memcpy. For the O32 case, this causes the caller to allocate
3363   // stack space for the reserved argument area for the callee, then recursively
3364   // again for the memcpy call. In the NEWABI case, this doesn't occur as those
3365   // ABIs mandate that the callee allocates the reserved argument area. We do
3366   // still produce nested CALLSEQ_START..CALLSEQ_END with zero space though.
3367   //
3368   // If the callee has a byval argument and memcpy is used, we are mandated
3369   // to already have produced a reserved argument area for the callee for O32.
3370   // Therefore, the reserved argument area can be reused for both calls.
3371   //
3372   // Other cases of calling memcpy cannot have a chain with a CALLSEQ_START
3373   // present, as we have yet to hook that node onto the chain.
3374   //
3375   // Hence, the CALLSEQ_START and CALLSEQ_END nodes can be eliminated in this
3376   // case. GCC does a similar trick, in that wherever possible, it calculates
3377   // the maximum out going argument area (including the reserved area), and
3378   // preallocates the stack space on entrance to the caller.
3379   //
3380   // FIXME: We should do the same for efficiency and space.
3381 
3382   // Note: The check on the calling convention below must match
3383   //       MipsABIInfo::GetCalleeAllocdArgSizeInBytes().
3384   bool MemcpyInByVal = ES && StringRef(ES->getSymbol()) == "memcpy" &&
3385                        CallConv != CallingConv::Fast &&
3386                        Chain.getOpcode() == ISD::CALLSEQ_START;
3387 
3388   // Allocate the reserved argument area. It seems strange to do this from the
3389   // caller side but removing it breaks the frame size calculation.
3390   unsigned ReservedArgArea =
3391       MemcpyInByVal ? 0 : ABI.GetCalleeAllocdArgSizeInBytes(CallConv);
3392   CCInfo.AllocateStack(ReservedArgArea, Align(1));
3393 
3394   CCInfo.AnalyzeCallOperands(Outs, CC_Mips, CLI.getArgs(),
3395                              ES ? ES->getSymbol() : nullptr);
3396 
3397   // Get a count of how many bytes are to be pushed on the stack.
3398   unsigned StackSize = CCInfo.getStackSize();
3399 
3400   // Call site info for function parameters tracking.
3401   MachineFunction::CallSiteInfo CSInfo;
3402 
3403   // Check if it's really possible to do a tail call. Restrict it to functions
3404   // that are part of this compilation unit.
3405   bool InternalLinkage = false;
3406   if (IsTailCall) {
3407     IsTailCall = isEligibleForTailCallOptimization(
3408         CCInfo, StackSize, *MF.getInfo<MipsFunctionInfo>());
3409     if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee)) {
3410       InternalLinkage = G->getGlobal()->hasInternalLinkage();
3411       IsTailCall &= (InternalLinkage || G->getGlobal()->hasLocalLinkage() ||
3412                      G->getGlobal()->hasPrivateLinkage() ||
3413                      G->getGlobal()->hasHiddenVisibility() ||
3414                      G->getGlobal()->hasProtectedVisibility());
3415      }
3416   }
3417   if (!IsTailCall && CLI.CB && CLI.CB->isMustTailCall())
3418     report_fatal_error("failed to perform tail call elimination on a call "
3419                        "site marked musttail");
3420 
3421   if (IsTailCall)
3422     ++NumTailCalls;
3423 
3424   // Chain is the output chain of the last Load/Store or CopyToReg node.
3425   // ByValChain is the output chain of the last Memcpy node created for copying
3426   // byval arguments to the stack.
3427   unsigned StackAlignment = TFL->getStackAlignment();
3428   StackSize = alignTo(StackSize, StackAlignment);
3429 
3430   if (!(IsTailCall || MemcpyInByVal))
3431     Chain = DAG.getCALLSEQ_START(Chain, StackSize, 0, DL);
3432 
3433   SDValue StackPtr =
3434       DAG.getCopyFromReg(Chain, DL, ABI.IsN64() ? Mips::SP_64 : Mips::SP,
3435                          getPointerTy(DAG.getDataLayout()));
3436   std::deque<std::pair<unsigned, SDValue>> RegsToPass;
3437   SmallVector<SDValue, 8> MemOpChains;
3438 
3439   CCInfo.rewindByValRegsInfo();
3440 
3441   // Walk the register/memloc assignments, inserting copies/loads.
3442   for (unsigned i = 0, e = ArgLocs.size(), OutIdx = 0; i != e; ++i, ++OutIdx) {
3443     SDValue Arg = OutVals[OutIdx];
3444     CCValAssign &VA = ArgLocs[i];
3445     MVT ValVT = VA.getValVT(), LocVT = VA.getLocVT();
3446     ISD::ArgFlagsTy Flags = Outs[OutIdx].Flags;
3447     bool UseUpperBits = false;
3448 
3449     // ByVal Arg.
3450     if (Flags.isByVal()) {
3451       unsigned FirstByValReg, LastByValReg;
3452       unsigned ByValIdx = CCInfo.getInRegsParamsProcessed();
3453       CCInfo.getInRegsParamInfo(ByValIdx, FirstByValReg, LastByValReg);
3454 
3455       assert(Flags.getByValSize() &&
3456              "ByVal args of size 0 should have been ignored by front-end.");
3457       assert(ByValIdx < CCInfo.getInRegsParamsCount());
3458       assert(!IsTailCall &&
3459              "Do not tail-call optimize if there is a byval argument.");
3460       passByValArg(Chain, DL, RegsToPass, MemOpChains, StackPtr, MFI, DAG, Arg,
3461                    FirstByValReg, LastByValReg, Flags, Subtarget.isLittle(),
3462                    VA);
3463       CCInfo.nextInRegsParam();
3464       continue;
3465     }
3466 
3467     // Promote the value if needed.
3468     switch (VA.getLocInfo()) {
3469     default:
3470       llvm_unreachable("Unknown loc info!");
3471     case CCValAssign::Full:
3472       if (VA.isRegLoc()) {
3473         if ((ValVT == MVT::f32 && LocVT == MVT::i32) ||
3474             (ValVT == MVT::f64 && LocVT == MVT::i64) ||
3475             (ValVT == MVT::i64 && LocVT == MVT::f64))
3476           Arg = DAG.getNode(ISD::BITCAST, DL, LocVT, Arg);
3477         else if (ValVT == MVT::f64 && LocVT == MVT::i32) {
3478           SDValue Lo = DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32,
3479                                    Arg, DAG.getConstant(0, DL, MVT::i32));
3480           SDValue Hi = DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32,
3481                                    Arg, DAG.getConstant(1, DL, MVT::i32));
3482           if (!Subtarget.isLittle())
3483             std::swap(Lo, Hi);
3484 
3485           assert(VA.needsCustom());
3486 
3487           Register LocRegLo = VA.getLocReg();
3488           Register LocRegHigh = ArgLocs[++i].getLocReg();
3489           RegsToPass.push_back(std::make_pair(LocRegLo, Lo));
3490           RegsToPass.push_back(std::make_pair(LocRegHigh, Hi));
3491           continue;
3492         }
3493       }
3494       break;
3495     case CCValAssign::BCvt:
3496       Arg = DAG.getNode(ISD::BITCAST, DL, LocVT, Arg);
3497       break;
3498     case CCValAssign::SExtUpper:
3499       UseUpperBits = true;
3500       [[fallthrough]];
3501     case CCValAssign::SExt:
3502       Arg = DAG.getNode(ISD::SIGN_EXTEND, DL, LocVT, Arg);
3503       break;
3504     case CCValAssign::ZExtUpper:
3505       UseUpperBits = true;
3506       [[fallthrough]];
3507     case CCValAssign::ZExt:
3508       Arg = DAG.getNode(ISD::ZERO_EXTEND, DL, LocVT, Arg);
3509       break;
3510     case CCValAssign::AExtUpper:
3511       UseUpperBits = true;
3512       [[fallthrough]];
3513     case CCValAssign::AExt:
3514       Arg = DAG.getNode(ISD::ANY_EXTEND, DL, LocVT, Arg);
3515       break;
3516     }
3517 
3518     if (UseUpperBits) {
3519       unsigned ValSizeInBits = Outs[OutIdx].ArgVT.getSizeInBits();
3520       unsigned LocSizeInBits = VA.getLocVT().getSizeInBits();
3521       Arg = DAG.getNode(
3522           ISD::SHL, DL, VA.getLocVT(), Arg,
3523           DAG.getConstant(LocSizeInBits - ValSizeInBits, DL, VA.getLocVT()));
3524     }
3525 
3526     // Arguments that can be passed on register must be kept at
3527     // RegsToPass vector
3528     if (VA.isRegLoc()) {
3529       RegsToPass.push_back(std::make_pair(VA.getLocReg(), Arg));
3530 
3531       // If the parameter is passed through reg $D, which splits into
3532       // two physical registers, avoid creating call site info.
3533       if (Mips::AFGR64RegClass.contains(VA.getLocReg()))
3534         continue;
3535 
3536       // Collect CSInfo about which register passes which parameter.
3537       const TargetOptions &Options = DAG.getTarget().Options;
3538       if (Options.EmitCallSiteInfo)
3539         CSInfo.ArgRegPairs.emplace_back(VA.getLocReg(), i);
3540 
3541       continue;
3542     }
3543 
3544     // Register can't get to this point...
3545     assert(VA.isMemLoc());
3546 
3547     // emit ISD::STORE whichs stores the
3548     // parameter value to a stack Location
3549     MemOpChains.push_back(passArgOnStack(StackPtr, VA.getLocMemOffset(),
3550                                          Chain, Arg, DL, IsTailCall, DAG));
3551   }
3552 
3553   // Transform all store nodes into one single node because all store
3554   // nodes are independent of each other.
3555   if (!MemOpChains.empty())
3556     Chain = DAG.getNode(ISD::TokenFactor, DL, MVT::Other, MemOpChains);
3557 
3558   // If the callee is a GlobalAddress/ExternalSymbol node (quite common, every
3559   // direct call is) turn it into a TargetGlobalAddress/TargetExternalSymbol
3560   // node so that legalize doesn't hack it.
3561 
3562   EVT Ty = Callee.getValueType();
3563   bool GlobalOrExternal = false, IsCallReloc = false;
3564 
3565   // The long-calls feature is ignored in case of PIC.
3566   // While we do not support -mshared / -mno-shared properly,
3567   // ignore long-calls in case of -mabicalls too.
3568   if (!Subtarget.isABICalls() && !IsPIC) {
3569     // If the function should be called using "long call",
3570     // get its address into a register to prevent using
3571     // of the `jal` instruction for the direct call.
3572     if (auto *N = dyn_cast<ExternalSymbolSDNode>(Callee)) {
3573       if (Subtarget.useLongCalls())
3574         Callee = Subtarget.hasSym32()
3575                      ? getAddrNonPIC(N, SDLoc(N), Ty, DAG)
3576                      : getAddrNonPICSym64(N, SDLoc(N), Ty, DAG);
3577     } else if (auto *N = dyn_cast<GlobalAddressSDNode>(Callee)) {
3578       bool UseLongCalls = Subtarget.useLongCalls();
3579       // If the function has long-call/far/near attribute
3580       // it overrides command line switch pased to the backend.
3581       if (auto *F = dyn_cast<Function>(N->getGlobal())) {
3582         if (F->hasFnAttribute("long-call"))
3583           UseLongCalls = true;
3584         else if (F->hasFnAttribute("short-call"))
3585           UseLongCalls = false;
3586       }
3587       if (UseLongCalls)
3588         Callee = Subtarget.hasSym32()
3589                      ? getAddrNonPIC(N, SDLoc(N), Ty, DAG)
3590                      : getAddrNonPICSym64(N, SDLoc(N), Ty, DAG);
3591     }
3592   }
3593 
3594   if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee)) {
3595     if (Subtarget.isTargetCOFF() &&
3596         G->getGlobal()->hasDLLImportStorageClass()) {
3597       assert(Subtarget.isTargetWindows() &&
3598              "Windows is the only supported COFF target");
3599       auto PtrInfo = MachinePointerInfo();
3600       Callee = DAG.getLoad(Ty, DL, Chain,
3601                            getDllimportSymbol(G, SDLoc(G), Ty, DAG), PtrInfo);
3602     } else if (IsPIC) {
3603       const GlobalValue *Val = G->getGlobal();
3604       InternalLinkage = Val->hasInternalLinkage();
3605 
3606       if (InternalLinkage)
3607         Callee = getAddrLocal(G, DL, Ty, DAG, ABI.IsN32() || ABI.IsN64());
3608       else if (Subtarget.useXGOT()) {
3609         Callee = getAddrGlobalLargeGOT(G, DL, Ty, DAG, MipsII::MO_CALL_HI16,
3610                                        MipsII::MO_CALL_LO16, Chain,
3611                                        FuncInfo->callPtrInfo(MF, Val));
3612         IsCallReloc = true;
3613       } else {
3614         Callee = getAddrGlobal(G, DL, Ty, DAG, MipsII::MO_GOT_CALL, Chain,
3615                                FuncInfo->callPtrInfo(MF, Val));
3616         IsCallReloc = true;
3617       }
3618     } else
3619       Callee = DAG.getTargetGlobalAddress(G->getGlobal(), DL,
3620                                           getPointerTy(DAG.getDataLayout()), 0,
3621                                           MipsII::MO_NO_FLAG);
3622     GlobalOrExternal = true;
3623   }
3624   else if (ExternalSymbolSDNode *S = dyn_cast<ExternalSymbolSDNode>(Callee)) {
3625     const char *Sym = S->getSymbol();
3626 
3627     if (!IsPIC) // static
3628       Callee = DAG.getTargetExternalSymbol(
3629           Sym, getPointerTy(DAG.getDataLayout()), MipsII::MO_NO_FLAG);
3630     else if (Subtarget.useXGOT()) {
3631       Callee = getAddrGlobalLargeGOT(S, DL, Ty, DAG, MipsII::MO_CALL_HI16,
3632                                      MipsII::MO_CALL_LO16, Chain,
3633                                      FuncInfo->callPtrInfo(MF, Sym));
3634       IsCallReloc = true;
3635     } else { // PIC
3636       Callee = getAddrGlobal(S, DL, Ty, DAG, MipsII::MO_GOT_CALL, Chain,
3637                              FuncInfo->callPtrInfo(MF, Sym));
3638       IsCallReloc = true;
3639     }
3640 
3641     GlobalOrExternal = true;
3642   }
3643 
3644   SmallVector<SDValue, 8> Ops(1, Chain);
3645   SDVTList NodeTys = DAG.getVTList(MVT::Other, MVT::Glue);
3646 
3647   getOpndList(Ops, RegsToPass, IsPIC, GlobalOrExternal, InternalLinkage,
3648               IsCallReloc, CLI, Callee, Chain);
3649 
3650   if (IsTailCall) {
3651     MF.getFrameInfo().setHasTailCall();
3652     SDValue Ret = DAG.getNode(MipsISD::TailCall, DL, MVT::Other, Ops);
3653     DAG.addCallSiteInfo(Ret.getNode(), std::move(CSInfo));
3654     return Ret;
3655   }
3656 
3657   Chain = DAG.getNode(MipsISD::JmpLink, DL, NodeTys, Ops);
3658   SDValue InGlue = Chain.getValue(1);
3659 
3660   DAG.addCallSiteInfo(Chain.getNode(), std::move(CSInfo));
3661 
3662   // Create the CALLSEQ_END node in the case of where it is not a call to
3663   // memcpy.
3664   if (!(MemcpyInByVal)) {
3665     Chain = DAG.getCALLSEQ_END(Chain, StackSize, 0, InGlue, DL);
3666     InGlue = Chain.getValue(1);
3667   }
3668 
3669   // Handle result values, copying them out of physregs into vregs that we
3670   // return.
3671   return LowerCallResult(Chain, InGlue, CallConv, IsVarArg, Ins, DL, DAG,
3672                          InVals, CLI);
3673 }
3674 
3675 /// LowerCallResult - Lower the result values of a call into the
3676 /// appropriate copies out of appropriate physical registers.
LowerCallResult(SDValue Chain,SDValue InGlue,CallingConv::ID CallConv,bool IsVarArg,const SmallVectorImpl<ISD::InputArg> & Ins,const SDLoc & DL,SelectionDAG & DAG,SmallVectorImpl<SDValue> & InVals,TargetLowering::CallLoweringInfo & CLI) const3677 SDValue MipsTargetLowering::LowerCallResult(
3678     SDValue Chain, SDValue InGlue, CallingConv::ID CallConv, bool IsVarArg,
3679     const SmallVectorImpl<ISD::InputArg> &Ins, const SDLoc &DL,
3680     SelectionDAG &DAG, SmallVectorImpl<SDValue> &InVals,
3681     TargetLowering::CallLoweringInfo &CLI) const {
3682   // Assign locations to each value returned by this call.
3683   SmallVector<CCValAssign, 16> RVLocs;
3684   MipsCCState CCInfo(CallConv, IsVarArg, DAG.getMachineFunction(), RVLocs,
3685                      *DAG.getContext());
3686 
3687   const ExternalSymbolSDNode *ES =
3688       dyn_cast_or_null<const ExternalSymbolSDNode>(CLI.Callee.getNode());
3689   CCInfo.AnalyzeCallResult(Ins, RetCC_Mips, CLI.RetTy,
3690                            ES ? ES->getSymbol() : nullptr);
3691 
3692   // Copy all of the result registers out of their specified physreg.
3693   for (unsigned i = 0; i != RVLocs.size(); ++i) {
3694     CCValAssign &VA = RVLocs[i];
3695     assert(VA.isRegLoc() && "Can only return in registers!");
3696 
3697     SDValue Val = DAG.getCopyFromReg(Chain, DL, RVLocs[i].getLocReg(),
3698                                      RVLocs[i].getLocVT(), InGlue);
3699     Chain = Val.getValue(1);
3700     InGlue = Val.getValue(2);
3701 
3702     if (VA.isUpperBitsInLoc()) {
3703       unsigned ValSizeInBits = Ins[i].ArgVT.getSizeInBits();
3704       unsigned LocSizeInBits = VA.getLocVT().getSizeInBits();
3705       unsigned Shift =
3706           VA.getLocInfo() == CCValAssign::ZExtUpper ? ISD::SRL : ISD::SRA;
3707       Val = DAG.getNode(
3708           Shift, DL, VA.getLocVT(), Val,
3709           DAG.getConstant(LocSizeInBits - ValSizeInBits, DL, VA.getLocVT()));
3710     }
3711 
3712     switch (VA.getLocInfo()) {
3713     default:
3714       llvm_unreachable("Unknown loc info!");
3715     case CCValAssign::Full:
3716       break;
3717     case CCValAssign::BCvt:
3718       Val = DAG.getNode(ISD::BITCAST, DL, VA.getValVT(), Val);
3719       break;
3720     case CCValAssign::AExt:
3721     case CCValAssign::AExtUpper:
3722       Val = DAG.getNode(ISD::TRUNCATE, DL, VA.getValVT(), Val);
3723       break;
3724     case CCValAssign::ZExt:
3725     case CCValAssign::ZExtUpper:
3726       Val = DAG.getNode(ISD::AssertZext, DL, VA.getLocVT(), Val,
3727                         DAG.getValueType(VA.getValVT()));
3728       Val = DAG.getNode(ISD::TRUNCATE, DL, VA.getValVT(), Val);
3729       break;
3730     case CCValAssign::SExt:
3731     case CCValAssign::SExtUpper:
3732       Val = DAG.getNode(ISD::AssertSext, DL, VA.getLocVT(), Val,
3733                         DAG.getValueType(VA.getValVT()));
3734       Val = DAG.getNode(ISD::TRUNCATE, DL, VA.getValVT(), Val);
3735       break;
3736     }
3737 
3738     InVals.push_back(Val);
3739   }
3740 
3741   return Chain;
3742 }
3743 
UnpackFromArgumentSlot(SDValue Val,const CCValAssign & VA,EVT ArgVT,const SDLoc & DL,SelectionDAG & DAG)3744 static SDValue UnpackFromArgumentSlot(SDValue Val, const CCValAssign &VA,
3745                                       EVT ArgVT, const SDLoc &DL,
3746                                       SelectionDAG &DAG) {
3747   MVT LocVT = VA.getLocVT();
3748   EVT ValVT = VA.getValVT();
3749 
3750   // Shift into the upper bits if necessary.
3751   switch (VA.getLocInfo()) {
3752   default:
3753     break;
3754   case CCValAssign::AExtUpper:
3755   case CCValAssign::SExtUpper:
3756   case CCValAssign::ZExtUpper: {
3757     unsigned ValSizeInBits = ArgVT.getSizeInBits();
3758     unsigned LocSizeInBits = VA.getLocVT().getSizeInBits();
3759     unsigned Opcode =
3760         VA.getLocInfo() == CCValAssign::ZExtUpper ? ISD::SRL : ISD::SRA;
3761     Val = DAG.getNode(
3762         Opcode, DL, VA.getLocVT(), Val,
3763         DAG.getConstant(LocSizeInBits - ValSizeInBits, DL, VA.getLocVT()));
3764     break;
3765   }
3766   }
3767 
3768   // If this is an value smaller than the argument slot size (32-bit for O32,
3769   // 64-bit for N32/N64), it has been promoted in some way to the argument slot
3770   // size. Extract the value and insert any appropriate assertions regarding
3771   // sign/zero extension.
3772   switch (VA.getLocInfo()) {
3773   default:
3774     llvm_unreachable("Unknown loc info!");
3775   case CCValAssign::Full:
3776     break;
3777   case CCValAssign::AExtUpper:
3778   case CCValAssign::AExt:
3779     Val = DAG.getNode(ISD::TRUNCATE, DL, ValVT, Val);
3780     break;
3781   case CCValAssign::SExtUpper:
3782   case CCValAssign::SExt:
3783     Val = DAG.getNode(ISD::AssertSext, DL, LocVT, Val, DAG.getValueType(ValVT));
3784     Val = DAG.getNode(ISD::TRUNCATE, DL, ValVT, Val);
3785     break;
3786   case CCValAssign::ZExtUpper:
3787   case CCValAssign::ZExt:
3788     Val = DAG.getNode(ISD::AssertZext, DL, LocVT, Val, DAG.getValueType(ValVT));
3789     Val = DAG.getNode(ISD::TRUNCATE, DL, ValVT, Val);
3790     break;
3791   case CCValAssign::BCvt:
3792     Val = DAG.getNode(ISD::BITCAST, DL, ValVT, Val);
3793     break;
3794   }
3795 
3796   return Val;
3797 }
3798 
3799 //===----------------------------------------------------------------------===//
3800 //             Formal Arguments Calling Convention Implementation
3801 //===----------------------------------------------------------------------===//
3802 /// LowerFormalArguments - transform physical registers into virtual registers
3803 /// and generate load operations for arguments places on the stack.
LowerFormalArguments(SDValue Chain,CallingConv::ID CallConv,bool IsVarArg,const SmallVectorImpl<ISD::InputArg> & Ins,const SDLoc & DL,SelectionDAG & DAG,SmallVectorImpl<SDValue> & InVals) const3804 SDValue MipsTargetLowering::LowerFormalArguments(
3805     SDValue Chain, CallingConv::ID CallConv, bool IsVarArg,
3806     const SmallVectorImpl<ISD::InputArg> &Ins, const SDLoc &DL,
3807     SelectionDAG &DAG, SmallVectorImpl<SDValue> &InVals) const {
3808   MachineFunction &MF = DAG.getMachineFunction();
3809   MachineFrameInfo &MFI = MF.getFrameInfo();
3810   MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
3811 
3812   MipsFI->setVarArgsFrameIndex(0);
3813 
3814   // Used with vargs to acumulate store chains.
3815   std::vector<SDValue> OutChains;
3816 
3817   // Assign locations to all of the incoming arguments.
3818   SmallVector<CCValAssign, 16> ArgLocs;
3819   MipsCCState CCInfo(CallConv, IsVarArg, DAG.getMachineFunction(), ArgLocs,
3820                      *DAG.getContext());
3821   CCInfo.AllocateStack(ABI.GetCalleeAllocdArgSizeInBytes(CallConv), Align(1));
3822   const Function &Func = DAG.getMachineFunction().getFunction();
3823   Function::const_arg_iterator FuncArg = Func.arg_begin();
3824 
3825   if (Func.hasFnAttribute("interrupt") && !Func.arg_empty())
3826     report_fatal_error(
3827         "Functions with the interrupt attribute cannot have arguments!");
3828 
3829   CCInfo.AnalyzeFormalArguments(Ins, CC_Mips_FixedArg);
3830   MipsFI->setFormalArgInfo(CCInfo.getStackSize(),
3831                            CCInfo.getInRegsParamsCount() > 0);
3832 
3833   unsigned CurArgIdx = 0;
3834   CCInfo.rewindByValRegsInfo();
3835 
3836   for (unsigned i = 0, e = ArgLocs.size(), InsIdx = 0; i != e; ++i, ++InsIdx) {
3837     CCValAssign &VA = ArgLocs[i];
3838     if (Ins[InsIdx].isOrigArg()) {
3839       std::advance(FuncArg, Ins[InsIdx].getOrigArgIndex() - CurArgIdx);
3840       CurArgIdx = Ins[InsIdx].getOrigArgIndex();
3841     }
3842     EVT ValVT = VA.getValVT();
3843     ISD::ArgFlagsTy Flags = Ins[InsIdx].Flags;
3844     bool IsRegLoc = VA.isRegLoc();
3845 
3846     if (Flags.isByVal()) {
3847       assert(Ins[InsIdx].isOrigArg() && "Byval arguments cannot be implicit");
3848       unsigned FirstByValReg, LastByValReg;
3849       unsigned ByValIdx = CCInfo.getInRegsParamsProcessed();
3850       CCInfo.getInRegsParamInfo(ByValIdx, FirstByValReg, LastByValReg);
3851 
3852       assert(Flags.getByValSize() &&
3853              "ByVal args of size 0 should have been ignored by front-end.");
3854       assert(ByValIdx < CCInfo.getInRegsParamsCount());
3855       copyByValRegs(Chain, DL, OutChains, DAG, Flags, InVals, &*FuncArg,
3856                     FirstByValReg, LastByValReg, VA, CCInfo);
3857       CCInfo.nextInRegsParam();
3858       continue;
3859     }
3860 
3861     // Arguments stored on registers
3862     if (IsRegLoc) {
3863       MVT RegVT = VA.getLocVT();
3864       Register ArgReg = VA.getLocReg();
3865       const TargetRegisterClass *RC = getRegClassFor(RegVT);
3866 
3867       // Transform the arguments stored on
3868       // physical registers into virtual ones
3869       unsigned Reg = addLiveIn(DAG.getMachineFunction(), ArgReg, RC);
3870       SDValue ArgValue = DAG.getCopyFromReg(Chain, DL, Reg, RegVT);
3871 
3872       ArgValue =
3873           UnpackFromArgumentSlot(ArgValue, VA, Ins[InsIdx].ArgVT, DL, DAG);
3874 
3875       // Handle floating point arguments passed in integer registers and
3876       // long double arguments passed in floating point registers.
3877       if ((RegVT == MVT::i32 && ValVT == MVT::f32) ||
3878           (RegVT == MVT::i64 && ValVT == MVT::f64) ||
3879           (RegVT == MVT::f64 && ValVT == MVT::i64))
3880         ArgValue = DAG.getNode(ISD::BITCAST, DL, ValVT, ArgValue);
3881       else if (ABI.IsO32() && RegVT == MVT::i32 &&
3882                ValVT == MVT::f64) {
3883         assert(VA.needsCustom() && "Expected custom argument for f64 split");
3884         CCValAssign &NextVA = ArgLocs[++i];
3885         unsigned Reg2 =
3886             addLiveIn(DAG.getMachineFunction(), NextVA.getLocReg(), RC);
3887         SDValue ArgValue2 = DAG.getCopyFromReg(Chain, DL, Reg2, RegVT);
3888         if (!Subtarget.isLittle())
3889           std::swap(ArgValue, ArgValue2);
3890         ArgValue = DAG.getNode(MipsISD::BuildPairF64, DL, MVT::f64,
3891                                ArgValue, ArgValue2);
3892       }
3893 
3894       InVals.push_back(ArgValue);
3895     } else { // VA.isRegLoc()
3896       MVT LocVT = VA.getLocVT();
3897 
3898       assert(!VA.needsCustom() && "unexpected custom memory argument");
3899 
3900       // Only arguments pased on the stack should make it here.
3901       assert(VA.isMemLoc());
3902 
3903       // The stack pointer offset is relative to the caller stack frame.
3904       int FI = MFI.CreateFixedObject(LocVT.getSizeInBits() / 8,
3905                                      VA.getLocMemOffset(), true);
3906 
3907       // Create load nodes to retrieve arguments from the stack
3908       SDValue FIN = DAG.getFrameIndex(FI, getPointerTy(DAG.getDataLayout()));
3909       SDValue ArgValue = DAG.getLoad(
3910           LocVT, DL, Chain, FIN,
3911           MachinePointerInfo::getFixedStack(DAG.getMachineFunction(), FI));
3912       OutChains.push_back(ArgValue.getValue(1));
3913 
3914       ArgValue =
3915           UnpackFromArgumentSlot(ArgValue, VA, Ins[InsIdx].ArgVT, DL, DAG);
3916 
3917       InVals.push_back(ArgValue);
3918     }
3919   }
3920 
3921   for (unsigned i = 0, e = ArgLocs.size(), InsIdx = 0; i != e; ++i, ++InsIdx) {
3922 
3923     if (ArgLocs[i].needsCustom()) {
3924       ++i;
3925       continue;
3926     }
3927 
3928     // The mips ABIs for returning structs by value requires that we copy
3929     // the sret argument into $v0 for the return. Save the argument into
3930     // a virtual register so that we can access it from the return points.
3931     if (Ins[InsIdx].Flags.isSRet()) {
3932       unsigned Reg = MipsFI->getSRetReturnReg();
3933       if (!Reg) {
3934         Reg = MF.getRegInfo().createVirtualRegister(
3935             getRegClassFor(ABI.IsN64() ? MVT::i64 : MVT::i32));
3936         MipsFI->setSRetReturnReg(Reg);
3937       }
3938       SDValue Copy = DAG.getCopyToReg(DAG.getEntryNode(), DL, Reg, InVals[i]);
3939       Chain = DAG.getNode(ISD::TokenFactor, DL, MVT::Other, Copy, Chain);
3940       break;
3941     }
3942   }
3943 
3944   if (IsVarArg)
3945     writeVarArgRegs(OutChains, Chain, DL, DAG, CCInfo);
3946 
3947   // All stores are grouped in one node to allow the matching between
3948   // the size of Ins and InVals. This only happens when on varg functions
3949   if (!OutChains.empty()) {
3950     OutChains.push_back(Chain);
3951     Chain = DAG.getNode(ISD::TokenFactor, DL, MVT::Other, OutChains);
3952   }
3953 
3954   return Chain;
3955 }
3956 
3957 //===----------------------------------------------------------------------===//
3958 //               Return Value Calling Convention Implementation
3959 //===----------------------------------------------------------------------===//
3960 
3961 bool
CanLowerReturn(CallingConv::ID CallConv,MachineFunction & MF,bool IsVarArg,const SmallVectorImpl<ISD::OutputArg> & Outs,LLVMContext & Context,const Type * RetTy) const3962 MipsTargetLowering::CanLowerReturn(CallingConv::ID CallConv,
3963                                    MachineFunction &MF, bool IsVarArg,
3964                                    const SmallVectorImpl<ISD::OutputArg> &Outs,
3965                                    LLVMContext &Context, const Type *RetTy) const {
3966   SmallVector<CCValAssign, 16> RVLocs;
3967   MipsCCState CCInfo(CallConv, IsVarArg, MF, RVLocs, Context);
3968   return CCInfo.CheckCallReturn(Outs, RetCC_Mips, RetTy);
3969 }
3970 
shouldSignExtendTypeInLibCall(Type * Ty,bool IsSigned) const3971 bool MipsTargetLowering::shouldSignExtendTypeInLibCall(Type *Ty,
3972                                                        bool IsSigned) const {
3973   if ((ABI.IsN32() || ABI.IsN64()) && Ty->isIntegerTy(32))
3974     return true;
3975 
3976   return IsSigned;
3977 }
3978 
3979 SDValue
LowerInterruptReturn(SmallVectorImpl<SDValue> & RetOps,const SDLoc & DL,SelectionDAG & DAG) const3980 MipsTargetLowering::LowerInterruptReturn(SmallVectorImpl<SDValue> &RetOps,
3981                                          const SDLoc &DL,
3982                                          SelectionDAG &DAG) const {
3983   MachineFunction &MF = DAG.getMachineFunction();
3984   MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
3985 
3986   MipsFI->setISR();
3987 
3988   return DAG.getNode(MipsISD::ERet, DL, MVT::Other, RetOps);
3989 }
3990 
3991 SDValue
LowerReturn(SDValue Chain,CallingConv::ID CallConv,bool IsVarArg,const SmallVectorImpl<ISD::OutputArg> & Outs,const SmallVectorImpl<SDValue> & OutVals,const SDLoc & DL,SelectionDAG & DAG) const3992 MipsTargetLowering::LowerReturn(SDValue Chain, CallingConv::ID CallConv,
3993                                 bool IsVarArg,
3994                                 const SmallVectorImpl<ISD::OutputArg> &Outs,
3995                                 const SmallVectorImpl<SDValue> &OutVals,
3996                                 const SDLoc &DL, SelectionDAG &DAG) const {
3997   // CCValAssign - represent the assignment of
3998   // the return value to a location
3999   SmallVector<CCValAssign, 16> RVLocs;
4000   MachineFunction &MF = DAG.getMachineFunction();
4001 
4002   // CCState - Info about the registers and stack slot.
4003   MipsCCState CCInfo(CallConv, IsVarArg, MF, RVLocs, *DAG.getContext());
4004 
4005   // Analyze return values.
4006   CCInfo.AnalyzeReturn(Outs, RetCC_Mips);
4007 
4008   SDValue Glue;
4009   SmallVector<SDValue, 4> RetOps(1, Chain);
4010 
4011   // Copy the result values into the output registers.
4012   for (unsigned i = 0; i != RVLocs.size(); ++i) {
4013     SDValue Val = OutVals[i];
4014     CCValAssign &VA = RVLocs[i];
4015     assert(VA.isRegLoc() && "Can only return in registers!");
4016     bool UseUpperBits = false;
4017 
4018     switch (VA.getLocInfo()) {
4019     default:
4020       llvm_unreachable("Unknown loc info!");
4021     case CCValAssign::Full:
4022       break;
4023     case CCValAssign::BCvt:
4024       Val = DAG.getNode(ISD::BITCAST, DL, VA.getLocVT(), Val);
4025       break;
4026     case CCValAssign::AExtUpper:
4027       UseUpperBits = true;
4028       [[fallthrough]];
4029     case CCValAssign::AExt:
4030       Val = DAG.getNode(ISD::ANY_EXTEND, DL, VA.getLocVT(), Val);
4031       break;
4032     case CCValAssign::ZExtUpper:
4033       UseUpperBits = true;
4034       [[fallthrough]];
4035     case CCValAssign::ZExt:
4036       Val = DAG.getNode(ISD::ZERO_EXTEND, DL, VA.getLocVT(), Val);
4037       break;
4038     case CCValAssign::SExtUpper:
4039       UseUpperBits = true;
4040       [[fallthrough]];
4041     case CCValAssign::SExt:
4042       Val = DAG.getNode(ISD::SIGN_EXTEND, DL, VA.getLocVT(), Val);
4043       break;
4044     }
4045 
4046     if (UseUpperBits) {
4047       unsigned ValSizeInBits = Outs[i].ArgVT.getSizeInBits();
4048       unsigned LocSizeInBits = VA.getLocVT().getSizeInBits();
4049       Val = DAG.getNode(
4050           ISD::SHL, DL, VA.getLocVT(), Val,
4051           DAG.getConstant(LocSizeInBits - ValSizeInBits, DL, VA.getLocVT()));
4052     }
4053 
4054     Chain = DAG.getCopyToReg(Chain, DL, VA.getLocReg(), Val, Glue);
4055 
4056     // Guarantee that all emitted copies are stuck together with flags.
4057     Glue = Chain.getValue(1);
4058     RetOps.push_back(DAG.getRegister(VA.getLocReg(), VA.getLocVT()));
4059   }
4060 
4061   // The mips ABIs for returning structs by value requires that we copy
4062   // the sret argument into $v0 for the return. We saved the argument into
4063   // a virtual register in the entry block, so now we copy the value out
4064   // and into $v0.
4065   if (MF.getFunction().hasStructRetAttr()) {
4066     MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
4067     unsigned Reg = MipsFI->getSRetReturnReg();
4068 
4069     if (!Reg)
4070       llvm_unreachable("sret virtual register not created in the entry block");
4071     SDValue Val =
4072         DAG.getCopyFromReg(Chain, DL, Reg, getPointerTy(DAG.getDataLayout()));
4073     unsigned V0 = ABI.IsN64() ? Mips::V0_64 : Mips::V0;
4074 
4075     Chain = DAG.getCopyToReg(Chain, DL, V0, Val, Glue);
4076     Glue = Chain.getValue(1);
4077     RetOps.push_back(DAG.getRegister(V0, getPointerTy(DAG.getDataLayout())));
4078   }
4079 
4080   RetOps[0] = Chain;  // Update chain.
4081 
4082   // Add the glue if we have it.
4083   if (Glue.getNode())
4084     RetOps.push_back(Glue);
4085 
4086   // ISRs must use "eret".
4087   if (DAG.getMachineFunction().getFunction().hasFnAttribute("interrupt"))
4088     return LowerInterruptReturn(RetOps, DL, DAG);
4089 
4090   // Standard return on Mips is a "jr $ra"
4091   return DAG.getNode(MipsISD::Ret, DL, MVT::Other, RetOps);
4092 }
4093 
4094 //===----------------------------------------------------------------------===//
4095 //                           Mips Inline Assembly Support
4096 //===----------------------------------------------------------------------===//
4097 
4098 /// getConstraintType - Given a constraint letter, return the type of
4099 /// constraint it is for this target.
4100 MipsTargetLowering::ConstraintType
getConstraintType(StringRef Constraint) const4101 MipsTargetLowering::getConstraintType(StringRef Constraint) const {
4102   // Mips specific constraints
4103   // GCC config/mips/constraints.md
4104   //
4105   // 'd' : An address register. Equivalent to r
4106   //       unless generating MIPS16 code.
4107   // 'y' : Equivalent to r; retained for
4108   //       backwards compatibility.
4109   // 'c' : A register suitable for use in an indirect
4110   //       jump. This will always be $25 for -mabicalls.
4111   // 'l' : The lo register. 1 word storage.
4112   // 'x' : The hilo register pair. Double word storage.
4113   if (Constraint.size() == 1) {
4114     switch (Constraint[0]) {
4115       default : break;
4116       case 'd':
4117       case 'y':
4118       case 'f':
4119       case 'c':
4120       case 'l':
4121       case 'x':
4122         return C_RegisterClass;
4123       case 'R':
4124         return C_Memory;
4125     }
4126   }
4127 
4128   if (Constraint == "ZC")
4129     return C_Memory;
4130 
4131   return TargetLowering::getConstraintType(Constraint);
4132 }
4133 
4134 /// Examine constraint type and operand type and determine a weight value.
4135 /// This object must already have been set up with the operand type
4136 /// and the current alternative constraint selected.
4137 TargetLowering::ConstraintWeight
getSingleConstraintMatchWeight(AsmOperandInfo & info,const char * constraint) const4138 MipsTargetLowering::getSingleConstraintMatchWeight(
4139     AsmOperandInfo &info, const char *constraint) const {
4140   ConstraintWeight weight = CW_Invalid;
4141   Value *CallOperandVal = info.CallOperandVal;
4142     // If we don't have a value, we can't do a match,
4143     // but allow it at the lowest weight.
4144   if (!CallOperandVal)
4145     return CW_Default;
4146   Type *type = CallOperandVal->getType();
4147   // Look at the constraint type.
4148   switch (*constraint) {
4149   default:
4150     weight = TargetLowering::getSingleConstraintMatchWeight(info, constraint);
4151     break;
4152   case 'd':
4153   case 'y':
4154     if (type->isIntegerTy())
4155       weight = CW_Register;
4156     break;
4157   case 'f': // FPU or MSA register
4158     if (Subtarget.hasMSA() && type->isVectorTy() &&
4159         type->getPrimitiveSizeInBits().getFixedValue() == 128)
4160       weight = CW_Register;
4161     else if (type->isFloatTy())
4162       weight = CW_Register;
4163     break;
4164   case 'c': // $25 for indirect jumps
4165   case 'l': // lo register
4166   case 'x': // hilo register pair
4167     if (type->isIntegerTy())
4168       weight = CW_SpecificReg;
4169     break;
4170   case 'I': // signed 16 bit immediate
4171   case 'J': // integer zero
4172   case 'K': // unsigned 16 bit immediate
4173   case 'L': // signed 32 bit immediate where lower 16 bits are 0
4174   case 'N': // immediate in the range of -65535 to -1 (inclusive)
4175   case 'O': // signed 15 bit immediate (+- 16383)
4176   case 'P': // immediate in the range of 65535 to 1 (inclusive)
4177     if (isa<ConstantInt>(CallOperandVal))
4178       weight = CW_Constant;
4179     break;
4180   case 'R':
4181     weight = CW_Memory;
4182     break;
4183   }
4184   return weight;
4185 }
4186 
4187 /// This is a helper function to parse a physical register string and split it
4188 /// into non-numeric and numeric parts (Prefix and Reg). The first boolean flag
4189 /// that is returned indicates whether parsing was successful. The second flag
4190 /// is true if the numeric part exists.
parsePhysicalReg(StringRef C,StringRef & Prefix,unsigned long long & Reg)4191 static std::pair<bool, bool> parsePhysicalReg(StringRef C, StringRef &Prefix,
4192                                               unsigned long long &Reg) {
4193   if (C.front() != '{' || C.back() != '}')
4194     return std::make_pair(false, false);
4195 
4196   // Search for the first numeric character.
4197   StringRef::const_iterator I, B = C.begin() + 1, E = C.end() - 1;
4198   I = std::find_if(B, E, isdigit);
4199 
4200   Prefix = StringRef(B, I - B);
4201 
4202   // The second flag is set to false if no numeric characters were found.
4203   if (I == E)
4204     return std::make_pair(true, false);
4205 
4206   // Parse the numeric characters.
4207   return std::make_pair(!getAsUnsignedInteger(StringRef(I, E - I), 10, Reg),
4208                         true);
4209 }
4210 
getTypeForExtReturn(LLVMContext & Context,EVT VT,ISD::NodeType) const4211 EVT MipsTargetLowering::getTypeForExtReturn(LLVMContext &Context, EVT VT,
4212                                             ISD::NodeType) const {
4213   bool Cond = !Subtarget.isABI_O32() && VT.getSizeInBits() == 32;
4214   EVT MinVT = getRegisterType(Cond ? MVT::i64 : MVT::i32);
4215   return VT.bitsLT(MinVT) ? MinVT : VT;
4216 }
4217 
4218 std::pair<unsigned, const TargetRegisterClass *> MipsTargetLowering::
parseRegForInlineAsmConstraint(StringRef C,MVT VT) const4219 parseRegForInlineAsmConstraint(StringRef C, MVT VT) const {
4220   const TargetRegisterInfo *TRI =
4221       Subtarget.getRegisterInfo();
4222   const TargetRegisterClass *RC;
4223   StringRef Prefix;
4224   unsigned long long Reg;
4225 
4226   std::pair<bool, bool> R = parsePhysicalReg(C, Prefix, Reg);
4227 
4228   if (!R.first)
4229     return std::make_pair(0U, nullptr);
4230 
4231   if ((Prefix == "hi" || Prefix == "lo")) { // Parse hi/lo.
4232     // No numeric characters follow "hi" or "lo".
4233     if (R.second)
4234       return std::make_pair(0U, nullptr);
4235 
4236     RC = TRI->getRegClass(Prefix == "hi" ?
4237                           Mips::HI32RegClassID : Mips::LO32RegClassID);
4238     return std::make_pair(*(RC->begin()), RC);
4239   } else if (Prefix.starts_with("$msa")) {
4240     // Parse $msa(ir|csr|access|save|modify|request|map|unmap)
4241 
4242     // No numeric characters follow the name.
4243     if (R.second)
4244       return std::make_pair(0U, nullptr);
4245 
4246     Reg = StringSwitch<unsigned long long>(Prefix)
4247               .Case("$msair", Mips::MSAIR)
4248               .Case("$msacsr", Mips::MSACSR)
4249               .Case("$msaaccess", Mips::MSAAccess)
4250               .Case("$msasave", Mips::MSASave)
4251               .Case("$msamodify", Mips::MSAModify)
4252               .Case("$msarequest", Mips::MSARequest)
4253               .Case("$msamap", Mips::MSAMap)
4254               .Case("$msaunmap", Mips::MSAUnmap)
4255               .Default(0);
4256 
4257     if (!Reg)
4258       return std::make_pair(0U, nullptr);
4259 
4260     RC = TRI->getRegClass(Mips::MSACtrlRegClassID);
4261     return std::make_pair(Reg, RC);
4262   }
4263 
4264   if (!R.second)
4265     return std::make_pair(0U, nullptr);
4266 
4267   if (Prefix == "$f") { // Parse $f0-$f31.
4268     // If the size of FP registers is 64-bit or Reg is an even number, select
4269     // the 64-bit register class. Otherwise, select the 32-bit register class.
4270     if (VT == MVT::Other)
4271       VT = (Subtarget.isFP64bit() || !(Reg % 2)) ? MVT::f64 : MVT::f32;
4272 
4273     RC = getRegClassFor(VT);
4274 
4275     if (RC == &Mips::AFGR64RegClass) {
4276       assert(Reg % 2 == 0);
4277       Reg >>= 1;
4278     }
4279   } else if (Prefix == "$fcc") // Parse $fcc0-$fcc7.
4280     RC = TRI->getRegClass(Mips::FCCRegClassID);
4281   else if (Prefix == "$w") { // Parse $w0-$w31.
4282     RC = getRegClassFor((VT == MVT::Other) ? MVT::v16i8 : VT);
4283   } else { // Parse $0-$31.
4284     assert(Prefix == "$");
4285     RC = getRegClassFor((VT == MVT::Other) ? MVT::i32 : VT);
4286   }
4287 
4288   assert(Reg < RC->getNumRegs());
4289   return std::make_pair(*(RC->begin() + Reg), RC);
4290 }
4291 
4292 /// Given a register class constraint, like 'r', if this corresponds directly
4293 /// to an LLVM register class, return a register of 0 and the register class
4294 /// pointer.
4295 std::pair<unsigned, const TargetRegisterClass *>
getRegForInlineAsmConstraint(const TargetRegisterInfo * TRI,StringRef Constraint,MVT VT) const4296 MipsTargetLowering::getRegForInlineAsmConstraint(const TargetRegisterInfo *TRI,
4297                                                  StringRef Constraint,
4298                                                  MVT VT) const {
4299   if (Constraint.size() == 1) {
4300     switch (Constraint[0]) {
4301     case 'd': // Address register. Same as 'r' unless generating MIPS16 code.
4302     case 'y': // Same as 'r'. Exists for compatibility.
4303     case 'r':
4304       if ((VT == MVT::i32 || VT == MVT::i16 || VT == MVT::i8 ||
4305            VT == MVT::i1) ||
4306           (VT == MVT::f32 && Subtarget.useSoftFloat())) {
4307         if (Subtarget.inMips16Mode())
4308           return std::make_pair(0U, &Mips::CPU16RegsRegClass);
4309         return std::make_pair(0U, &Mips::GPR32RegClass);
4310       }
4311       if ((VT == MVT::i64 || (VT == MVT::f64 && Subtarget.useSoftFloat())) &&
4312           !Subtarget.isGP64bit())
4313         return std::make_pair(0U, &Mips::GPR32RegClass);
4314       if ((VT == MVT::i64 || (VT == MVT::f64 && Subtarget.useSoftFloat())) &&
4315           Subtarget.isGP64bit())
4316         return std::make_pair(0U, &Mips::GPR64RegClass);
4317       // This will generate an error message
4318       return std::make_pair(0U, nullptr);
4319     case 'f': // FPU or MSA register
4320       if (VT == MVT::v16i8)
4321         return std::make_pair(0U, &Mips::MSA128BRegClass);
4322       else if (VT == MVT::v8i16 || VT == MVT::v8f16)
4323         return std::make_pair(0U, &Mips::MSA128HRegClass);
4324       else if (VT == MVT::v4i32 || VT == MVT::v4f32)
4325         return std::make_pair(0U, &Mips::MSA128WRegClass);
4326       else if (VT == MVT::v2i64 || VT == MVT::v2f64)
4327         return std::make_pair(0U, &Mips::MSA128DRegClass);
4328       else if (VT == MVT::f32)
4329         return std::make_pair(0U, &Mips::FGR32RegClass);
4330       else if ((VT == MVT::f64) && (!Subtarget.isSingleFloat())) {
4331         if (Subtarget.isFP64bit())
4332           return std::make_pair(0U, &Mips::FGR64RegClass);
4333         return std::make_pair(0U, &Mips::AFGR64RegClass);
4334       }
4335       break;
4336     case 'c': // register suitable for indirect jump
4337       if (VT == MVT::i32)
4338         return std::make_pair((unsigned)Mips::T9, &Mips::GPR32RegClass);
4339       if (VT == MVT::i64)
4340         return std::make_pair((unsigned)Mips::T9_64, &Mips::GPR64RegClass);
4341       // This will generate an error message
4342       return std::make_pair(0U, nullptr);
4343     case 'l': // use the `lo` register to store values
4344               // that are no bigger than a word
4345       if (VT == MVT::i32 || VT == MVT::i16 || VT == MVT::i8)
4346         return std::make_pair((unsigned)Mips::LO0, &Mips::LO32RegClass);
4347       return std::make_pair((unsigned)Mips::LO0_64, &Mips::LO64RegClass);
4348     case 'x': // use the concatenated `hi` and `lo` registers
4349               // to store doubleword values
4350       // Fixme: Not triggering the use of both hi and low
4351       // This will generate an error message
4352       return std::make_pair(0U, nullptr);
4353     }
4354   }
4355 
4356   if (!Constraint.empty()) {
4357     std::pair<unsigned, const TargetRegisterClass *> R;
4358     R = parseRegForInlineAsmConstraint(Constraint, VT);
4359 
4360     if (R.second)
4361       return R;
4362   }
4363 
4364   return TargetLowering::getRegForInlineAsmConstraint(TRI, Constraint, VT);
4365 }
4366 
4367 /// LowerAsmOperandForConstraint - Lower the specified operand into the Ops
4368 /// vector.  If it is invalid, don't add anything to Ops.
LowerAsmOperandForConstraint(SDValue Op,StringRef Constraint,std::vector<SDValue> & Ops,SelectionDAG & DAG) const4369 void MipsTargetLowering::LowerAsmOperandForConstraint(SDValue Op,
4370                                                       StringRef Constraint,
4371                                                       std::vector<SDValue> &Ops,
4372                                                       SelectionDAG &DAG) const {
4373   SDLoc DL(Op);
4374   SDValue Result;
4375 
4376   // Only support length 1 constraints for now.
4377   if (Constraint.size() > 1)
4378     return;
4379 
4380   char ConstraintLetter = Constraint[0];
4381   switch (ConstraintLetter) {
4382   default: break; // This will fall through to the generic implementation
4383   case 'I': // Signed 16 bit constant
4384     // If this fails, the parent routine will give an error
4385     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
4386       EVT Type = Op.getValueType();
4387       int64_t Val = C->getSExtValue();
4388       if (isInt<16>(Val)) {
4389         Result = DAG.getSignedTargetConstant(Val, DL, Type);
4390         break;
4391       }
4392     }
4393     return;
4394   case 'J': // integer zero
4395     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
4396       EVT Type = Op.getValueType();
4397       int64_t Val = C->getZExtValue();
4398       if (Val == 0) {
4399         Result = DAG.getTargetConstant(0, DL, Type);
4400         break;
4401       }
4402     }
4403     return;
4404   case 'K': // unsigned 16 bit immediate
4405     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
4406       EVT Type = Op.getValueType();
4407       uint64_t Val = (uint64_t)C->getZExtValue();
4408       if (isUInt<16>(Val)) {
4409         Result = DAG.getTargetConstant(Val, DL, Type);
4410         break;
4411       }
4412     }
4413     return;
4414   case 'L': // signed 32 bit immediate where lower 16 bits are 0
4415     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
4416       EVT Type = Op.getValueType();
4417       int64_t Val = C->getSExtValue();
4418       if ((isInt<32>(Val)) && ((Val & 0xffff) == 0)){
4419         Result = DAG.getSignedTargetConstant(Val, DL, Type);
4420         break;
4421       }
4422     }
4423     return;
4424   case 'N': // immediate in the range of -65535 to -1 (inclusive)
4425     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
4426       EVT Type = Op.getValueType();
4427       int64_t Val = C->getSExtValue();
4428       if ((Val >= -65535) && (Val <= -1)) {
4429         Result = DAG.getSignedTargetConstant(Val, DL, Type);
4430         break;
4431       }
4432     }
4433     return;
4434   case 'O': // signed 15 bit immediate
4435     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
4436       EVT Type = Op.getValueType();
4437       int64_t Val = C->getSExtValue();
4438       if ((isInt<15>(Val))) {
4439         Result = DAG.getSignedTargetConstant(Val, DL, Type);
4440         break;
4441       }
4442     }
4443     return;
4444   case 'P': // immediate in the range of 1 to 65535 (inclusive)
4445     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
4446       EVT Type = Op.getValueType();
4447       int64_t Val = C->getSExtValue();
4448       if ((Val <= 65535) && (Val >= 1)) {
4449         Result = DAG.getTargetConstant(Val, DL, Type);
4450         break;
4451       }
4452     }
4453     return;
4454   }
4455 
4456   if (Result.getNode()) {
4457     Ops.push_back(Result);
4458     return;
4459   }
4460 
4461   TargetLowering::LowerAsmOperandForConstraint(Op, Constraint, Ops, DAG);
4462 }
4463 
isLegalAddressingMode(const DataLayout & DL,const AddrMode & AM,Type * Ty,unsigned AS,Instruction * I) const4464 bool MipsTargetLowering::isLegalAddressingMode(const DataLayout &DL,
4465                                                const AddrMode &AM, Type *Ty,
4466                                                unsigned AS,
4467                                                Instruction *I) const {
4468   // No global is ever allowed as a base.
4469   if (AM.BaseGV)
4470     return false;
4471 
4472   switch (AM.Scale) {
4473   case 0: // "r+i" or just "i", depending on HasBaseReg.
4474     break;
4475   case 1:
4476     if (!AM.HasBaseReg) // allow "r+i".
4477       break;
4478     return false; // disallow "r+r" or "r+r+i".
4479   default:
4480     return false;
4481   }
4482 
4483   return true;
4484 }
4485 
4486 bool
isOffsetFoldingLegal(const GlobalAddressSDNode * GA) const4487 MipsTargetLowering::isOffsetFoldingLegal(const GlobalAddressSDNode *GA) const {
4488   // The Mips target isn't yet aware of offsets.
4489   return false;
4490 }
4491 
getOptimalMemOpType(LLVMContext & Context,const MemOp & Op,const AttributeList & FuncAttributes) const4492 EVT MipsTargetLowering::getOptimalMemOpType(
4493     LLVMContext &Context, const MemOp &Op,
4494     const AttributeList &FuncAttributes) const {
4495   if (Subtarget.hasMips64())
4496     return MVT::i64;
4497 
4498   return MVT::i32;
4499 }
4500 
isFPImmLegal(const APFloat & Imm,EVT VT,bool ForCodeSize) const4501 bool MipsTargetLowering::isFPImmLegal(const APFloat &Imm, EVT VT,
4502                                       bool ForCodeSize) const {
4503   if (VT != MVT::f32 && VT != MVT::f64)
4504     return false;
4505   if (Imm.isNegZero())
4506     return false;
4507   return Imm.isZero();
4508 }
4509 
isLegalICmpImmediate(int64_t Imm) const4510 bool MipsTargetLowering::isLegalICmpImmediate(int64_t Imm) const {
4511   return isInt<16>(Imm);
4512 }
4513 
isLegalAddImmediate(int64_t Imm) const4514 bool MipsTargetLowering::isLegalAddImmediate(int64_t Imm) const {
4515   return isInt<16>(Imm);
4516 }
4517 
getJumpTableEncoding() const4518 unsigned MipsTargetLowering::getJumpTableEncoding() const {
4519   if (!isPositionIndependent())
4520     return MachineJumpTableInfo::EK_BlockAddress;
4521   if (ABI.IsN64())
4522     return MachineJumpTableInfo::EK_GPRel64BlockAddress;
4523   return MachineJumpTableInfo::EK_GPRel32BlockAddress;
4524 }
4525 
getPICJumpTableRelocBase(SDValue Table,SelectionDAG & DAG) const4526 SDValue MipsTargetLowering::getPICJumpTableRelocBase(SDValue Table,
4527                                                      SelectionDAG &DAG) const {
4528   if (!isPositionIndependent())
4529     return Table;
4530   return DAG.getGLOBAL_OFFSET_TABLE(getPointerTy(DAG.getDataLayout()));
4531 }
4532 
useSoftFloat() const4533 bool MipsTargetLowering::useSoftFloat() const {
4534   return Subtarget.useSoftFloat();
4535 }
4536 
copyByValRegs(SDValue Chain,const SDLoc & DL,std::vector<SDValue> & OutChains,SelectionDAG & DAG,const ISD::ArgFlagsTy & Flags,SmallVectorImpl<SDValue> & InVals,const Argument * FuncArg,unsigned FirstReg,unsigned LastReg,const CCValAssign & VA,MipsCCState & State) const4537 void MipsTargetLowering::copyByValRegs(
4538     SDValue Chain, const SDLoc &DL, std::vector<SDValue> &OutChains,
4539     SelectionDAG &DAG, const ISD::ArgFlagsTy &Flags,
4540     SmallVectorImpl<SDValue> &InVals, const Argument *FuncArg,
4541     unsigned FirstReg, unsigned LastReg, const CCValAssign &VA,
4542     MipsCCState &State) const {
4543   MachineFunction &MF = DAG.getMachineFunction();
4544   MachineFrameInfo &MFI = MF.getFrameInfo();
4545   unsigned GPRSizeInBytes = Subtarget.getGPRSizeInBytes();
4546   unsigned NumRegs = LastReg - FirstReg;
4547   unsigned RegAreaSize = NumRegs * GPRSizeInBytes;
4548   unsigned FrameObjSize = std::max(Flags.getByValSize(), RegAreaSize);
4549   int FrameObjOffset;
4550   ArrayRef<MCPhysReg> ByValArgRegs = ABI.GetByValArgRegs();
4551 
4552   if (RegAreaSize)
4553     FrameObjOffset =
4554         (int)ABI.GetCalleeAllocdArgSizeInBytes(State.getCallingConv()) -
4555         (int)((ByValArgRegs.size() - FirstReg) * GPRSizeInBytes);
4556   else
4557     FrameObjOffset = VA.getLocMemOffset();
4558 
4559   // Create frame object.
4560   EVT PtrTy = getPointerTy(DAG.getDataLayout());
4561   // Make the fixed object stored to mutable so that the load instructions
4562   // referencing it have their memory dependencies added.
4563   // Set the frame object as isAliased which clears the underlying objects
4564   // vector in ScheduleDAGInstrs::buildSchedGraph() resulting in addition of all
4565   // stores as dependencies for loads referencing this fixed object.
4566   int FI = MFI.CreateFixedObject(FrameObjSize, FrameObjOffset, false, true);
4567   SDValue FIN = DAG.getFrameIndex(FI, PtrTy);
4568   InVals.push_back(FIN);
4569 
4570   if (!NumRegs)
4571     return;
4572 
4573   // Copy arg registers.
4574   MVT RegTy = MVT::getIntegerVT(GPRSizeInBytes * 8);
4575   const TargetRegisterClass *RC = getRegClassFor(RegTy);
4576 
4577   for (unsigned I = 0; I < NumRegs; ++I) {
4578     unsigned ArgReg = ByValArgRegs[FirstReg + I];
4579     unsigned VReg = addLiveIn(MF, ArgReg, RC);
4580     unsigned Offset = I * GPRSizeInBytes;
4581     SDValue StorePtr = DAG.getNode(ISD::ADD, DL, PtrTy, FIN,
4582                                    DAG.getConstant(Offset, DL, PtrTy));
4583     SDValue Store = DAG.getStore(Chain, DL, DAG.getRegister(VReg, RegTy),
4584                                  StorePtr, MachinePointerInfo(FuncArg, Offset));
4585     OutChains.push_back(Store);
4586   }
4587 }
4588 
4589 // Copy byVal arg to registers and stack.
passByValArg(SDValue Chain,const SDLoc & DL,std::deque<std::pair<unsigned,SDValue>> & RegsToPass,SmallVectorImpl<SDValue> & MemOpChains,SDValue StackPtr,MachineFrameInfo & MFI,SelectionDAG & DAG,SDValue Arg,unsigned FirstReg,unsigned LastReg,const ISD::ArgFlagsTy & Flags,bool isLittle,const CCValAssign & VA) const4590 void MipsTargetLowering::passByValArg(
4591     SDValue Chain, const SDLoc &DL,
4592     std::deque<std::pair<unsigned, SDValue>> &RegsToPass,
4593     SmallVectorImpl<SDValue> &MemOpChains, SDValue StackPtr,
4594     MachineFrameInfo &MFI, SelectionDAG &DAG, SDValue Arg, unsigned FirstReg,
4595     unsigned LastReg, const ISD::ArgFlagsTy &Flags, bool isLittle,
4596     const CCValAssign &VA) const {
4597   unsigned ByValSizeInBytes = Flags.getByValSize();
4598   unsigned OffsetInBytes = 0; // From beginning of struct
4599   unsigned RegSizeInBytes = Subtarget.getGPRSizeInBytes();
4600   Align Alignment =
4601       std::min(Flags.getNonZeroByValAlign(), Align(RegSizeInBytes));
4602   EVT PtrTy = getPointerTy(DAG.getDataLayout()),
4603       RegTy = MVT::getIntegerVT(RegSizeInBytes * 8);
4604   unsigned NumRegs = LastReg - FirstReg;
4605 
4606   if (NumRegs) {
4607     ArrayRef<MCPhysReg> ArgRegs = ABI.GetByValArgRegs();
4608     bool LeftoverBytes = (NumRegs * RegSizeInBytes > ByValSizeInBytes);
4609     unsigned I = 0;
4610 
4611     // Copy words to registers.
4612     for (; I < NumRegs - LeftoverBytes; ++I, OffsetInBytes += RegSizeInBytes) {
4613       SDValue LoadPtr = DAG.getNode(ISD::ADD, DL, PtrTy, Arg,
4614                                     DAG.getConstant(OffsetInBytes, DL, PtrTy));
4615       SDValue LoadVal = DAG.getLoad(RegTy, DL, Chain, LoadPtr,
4616                                     MachinePointerInfo(), Alignment);
4617       MemOpChains.push_back(LoadVal.getValue(1));
4618       unsigned ArgReg = ArgRegs[FirstReg + I];
4619       RegsToPass.push_back(std::make_pair(ArgReg, LoadVal));
4620     }
4621 
4622     // Return if the struct has been fully copied.
4623     if (ByValSizeInBytes == OffsetInBytes)
4624       return;
4625 
4626     // Copy the remainder of the byval argument with sub-word loads and shifts.
4627     if (LeftoverBytes) {
4628       SDValue Val;
4629 
4630       for (unsigned LoadSizeInBytes = RegSizeInBytes / 2, TotalBytesLoaded = 0;
4631            OffsetInBytes < ByValSizeInBytes; LoadSizeInBytes /= 2) {
4632         unsigned RemainingSizeInBytes = ByValSizeInBytes - OffsetInBytes;
4633 
4634         if (RemainingSizeInBytes < LoadSizeInBytes)
4635           continue;
4636 
4637         // Load subword.
4638         SDValue LoadPtr = DAG.getNode(ISD::ADD, DL, PtrTy, Arg,
4639                                       DAG.getConstant(OffsetInBytes, DL,
4640                                                       PtrTy));
4641         SDValue LoadVal = DAG.getExtLoad(
4642             ISD::ZEXTLOAD, DL, RegTy, Chain, LoadPtr, MachinePointerInfo(),
4643             MVT::getIntegerVT(LoadSizeInBytes * 8), Alignment);
4644         MemOpChains.push_back(LoadVal.getValue(1));
4645 
4646         // Shift the loaded value.
4647         unsigned Shamt;
4648 
4649         if (isLittle)
4650           Shamt = TotalBytesLoaded * 8;
4651         else
4652           Shamt = (RegSizeInBytes - (TotalBytesLoaded + LoadSizeInBytes)) * 8;
4653 
4654         SDValue Shift = DAG.getNode(ISD::SHL, DL, RegTy, LoadVal,
4655                                     DAG.getConstant(Shamt, DL, MVT::i32));
4656 
4657         if (Val.getNode())
4658           Val = DAG.getNode(ISD::OR, DL, RegTy, Val, Shift);
4659         else
4660           Val = Shift;
4661 
4662         OffsetInBytes += LoadSizeInBytes;
4663         TotalBytesLoaded += LoadSizeInBytes;
4664         Alignment = std::min(Alignment, Align(LoadSizeInBytes));
4665       }
4666 
4667       unsigned ArgReg = ArgRegs[FirstReg + I];
4668       RegsToPass.push_back(std::make_pair(ArgReg, Val));
4669       return;
4670     }
4671   }
4672 
4673   // Copy remainder of byval arg to it with memcpy.
4674   unsigned MemCpySize = ByValSizeInBytes - OffsetInBytes;
4675   SDValue Src = DAG.getNode(ISD::ADD, DL, PtrTy, Arg,
4676                             DAG.getConstant(OffsetInBytes, DL, PtrTy));
4677   SDValue Dst = DAG.getNode(ISD::ADD, DL, PtrTy, StackPtr,
4678                             DAG.getIntPtrConstant(VA.getLocMemOffset(), DL));
4679   Chain = DAG.getMemcpy(
4680       Chain, DL, Dst, Src, DAG.getConstant(MemCpySize, DL, PtrTy),
4681       Align(Alignment), /*isVolatile=*/false, /*AlwaysInline=*/false,
4682       /*CI=*/nullptr, std::nullopt, MachinePointerInfo(), MachinePointerInfo());
4683   MemOpChains.push_back(Chain);
4684 }
4685 
writeVarArgRegs(std::vector<SDValue> & OutChains,SDValue Chain,const SDLoc & DL,SelectionDAG & DAG,CCState & State) const4686 void MipsTargetLowering::writeVarArgRegs(std::vector<SDValue> &OutChains,
4687                                          SDValue Chain, const SDLoc &DL,
4688                                          SelectionDAG &DAG,
4689                                          CCState &State) const {
4690   ArrayRef<MCPhysReg> ArgRegs = ABI.getVarArgRegs(Subtarget.isGP64bit());
4691   unsigned Idx = State.getFirstUnallocated(ArgRegs);
4692   unsigned RegSizeInBytes = Subtarget.getGPRSizeInBytes();
4693   MVT RegTy = MVT::getIntegerVT(RegSizeInBytes * 8);
4694   const TargetRegisterClass *RC = getRegClassFor(RegTy);
4695   MachineFunction &MF = DAG.getMachineFunction();
4696   MachineFrameInfo &MFI = MF.getFrameInfo();
4697   MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
4698 
4699   // Offset of the first variable argument from stack pointer.
4700   int VaArgOffset;
4701 
4702   if (ArgRegs.size() == Idx)
4703     VaArgOffset = alignTo(State.getStackSize(), RegSizeInBytes);
4704   else {
4705     VaArgOffset =
4706         (int)ABI.GetCalleeAllocdArgSizeInBytes(State.getCallingConv()) -
4707         (int)(RegSizeInBytes * (ArgRegs.size() - Idx));
4708   }
4709 
4710   // Record the frame index of the first variable argument
4711   // which is a value necessary to VASTART.
4712   int FI = MFI.CreateFixedObject(RegSizeInBytes, VaArgOffset, true);
4713   MipsFI->setVarArgsFrameIndex(FI);
4714 
4715   // Copy the integer registers that have not been used for argument passing
4716   // to the argument register save area. For O32, the save area is allocated
4717   // in the caller's stack frame, while for N32/64, it is allocated in the
4718   // callee's stack frame.
4719   for (unsigned I = Idx; I < ArgRegs.size();
4720        ++I, VaArgOffset += RegSizeInBytes) {
4721     unsigned Reg = addLiveIn(MF, ArgRegs[I], RC);
4722     SDValue ArgValue = DAG.getCopyFromReg(Chain, DL, Reg, RegTy);
4723     FI = MFI.CreateFixedObject(RegSizeInBytes, VaArgOffset, true);
4724     SDValue PtrOff = DAG.getFrameIndex(FI, getPointerTy(DAG.getDataLayout()));
4725     SDValue Store =
4726         DAG.getStore(Chain, DL, ArgValue, PtrOff, MachinePointerInfo());
4727     cast<StoreSDNode>(Store.getNode())->getMemOperand()->setValue(
4728         (Value *)nullptr);
4729     OutChains.push_back(Store);
4730   }
4731 }
4732 
HandleByVal(CCState * State,unsigned & Size,Align Alignment) const4733 void MipsTargetLowering::HandleByVal(CCState *State, unsigned &Size,
4734                                      Align Alignment) const {
4735   const TargetFrameLowering *TFL = Subtarget.getFrameLowering();
4736 
4737   assert(Size && "Byval argument's size shouldn't be 0.");
4738 
4739   Alignment = std::min(Alignment, TFL->getStackAlign());
4740 
4741   unsigned FirstReg = 0;
4742   unsigned NumRegs = 0;
4743 
4744   if (State->getCallingConv() != CallingConv::Fast) {
4745     unsigned RegSizeInBytes = Subtarget.getGPRSizeInBytes();
4746     ArrayRef<MCPhysReg> IntArgRegs = ABI.GetByValArgRegs();
4747     // FIXME: The O32 case actually describes no shadow registers.
4748     const MCPhysReg *ShadowRegs =
4749         ABI.IsO32() ? IntArgRegs.data() : Mips64DPRegs;
4750 
4751     // We used to check the size as well but we can't do that anymore since
4752     // CCState::HandleByVal() rounds up the size after calling this function.
4753     assert(
4754         Alignment >= Align(RegSizeInBytes) &&
4755         "Byval argument's alignment should be a multiple of RegSizeInBytes.");
4756 
4757     FirstReg = State->getFirstUnallocated(IntArgRegs);
4758 
4759     // If Alignment > RegSizeInBytes, the first arg register must be even.
4760     // FIXME: This condition happens to do the right thing but it's not the
4761     //        right way to test it. We want to check that the stack frame offset
4762     //        of the register is aligned.
4763     if ((Alignment > RegSizeInBytes) && (FirstReg % 2)) {
4764       State->AllocateReg(IntArgRegs[FirstReg], ShadowRegs[FirstReg]);
4765       ++FirstReg;
4766     }
4767 
4768     // Mark the registers allocated.
4769     Size = alignTo(Size, RegSizeInBytes);
4770     for (unsigned I = FirstReg; Size > 0 && (I < IntArgRegs.size());
4771          Size -= RegSizeInBytes, ++I, ++NumRegs)
4772       State->AllocateReg(IntArgRegs[I], ShadowRegs[I]);
4773   }
4774 
4775   State->addInRegsParamInfo(FirstReg, FirstReg + NumRegs);
4776 }
4777 
emitPseudoSELECT(MachineInstr & MI,MachineBasicBlock * BB,bool isFPCmp,unsigned Opc) const4778 MachineBasicBlock *MipsTargetLowering::emitPseudoSELECT(MachineInstr &MI,
4779                                                         MachineBasicBlock *BB,
4780                                                         bool isFPCmp,
4781                                                         unsigned Opc) const {
4782   assert(!(Subtarget.hasMips4() || Subtarget.hasMips32()) &&
4783          "Subtarget already supports SELECT nodes with the use of"
4784          "conditional-move instructions.");
4785 
4786   const TargetInstrInfo *TII =
4787       Subtarget.getInstrInfo();
4788   DebugLoc DL = MI.getDebugLoc();
4789 
4790   // To "insert" a SELECT instruction, we actually have to insert the
4791   // diamond control-flow pattern.  The incoming instruction knows the
4792   // destination vreg to set, the condition code register to branch on, the
4793   // true/false values to select between, and a branch opcode to use.
4794   const BasicBlock *LLVM_BB = BB->getBasicBlock();
4795   MachineFunction::iterator It = ++BB->getIterator();
4796 
4797   //  thisMBB:
4798   //  ...
4799   //   TrueVal = ...
4800   //   setcc r1, r2, r3
4801   //   bNE   r1, r0, copy1MBB
4802   //   fallthrough --> copy0MBB
4803   MachineBasicBlock *thisMBB  = BB;
4804   MachineFunction *F = BB->getParent();
4805   MachineBasicBlock *copy0MBB = F->CreateMachineBasicBlock(LLVM_BB);
4806   MachineBasicBlock *sinkMBB  = F->CreateMachineBasicBlock(LLVM_BB);
4807   F->insert(It, copy0MBB);
4808   F->insert(It, sinkMBB);
4809 
4810   // Transfer the remainder of BB and its successor edges to sinkMBB.
4811   sinkMBB->splice(sinkMBB->begin(), BB,
4812                   std::next(MachineBasicBlock::iterator(MI)), BB->end());
4813   sinkMBB->transferSuccessorsAndUpdatePHIs(BB);
4814 
4815   // Next, add the true and fallthrough blocks as its successors.
4816   BB->addSuccessor(copy0MBB);
4817   BB->addSuccessor(sinkMBB);
4818 
4819   if (isFPCmp) {
4820     // bc1[tf] cc, sinkMBB
4821     BuildMI(BB, DL, TII->get(Opc))
4822         .addReg(MI.getOperand(1).getReg())
4823         .addMBB(sinkMBB);
4824   } else {
4825     // bne rs, $0, sinkMBB
4826     BuildMI(BB, DL, TII->get(Opc))
4827         .addReg(MI.getOperand(1).getReg())
4828         .addReg(Mips::ZERO)
4829         .addMBB(sinkMBB);
4830   }
4831 
4832   //  copy0MBB:
4833   //   %FalseValue = ...
4834   //   # fallthrough to sinkMBB
4835   BB = copy0MBB;
4836 
4837   // Update machine-CFG edges
4838   BB->addSuccessor(sinkMBB);
4839 
4840   //  sinkMBB:
4841   //   %Result = phi [ %TrueValue, thisMBB ], [ %FalseValue, copy0MBB ]
4842   //  ...
4843   BB = sinkMBB;
4844 
4845   BuildMI(*BB, BB->begin(), DL, TII->get(Mips::PHI), MI.getOperand(0).getReg())
4846       .addReg(MI.getOperand(2).getReg())
4847       .addMBB(thisMBB)
4848       .addReg(MI.getOperand(3).getReg())
4849       .addMBB(copy0MBB);
4850 
4851   MI.eraseFromParent(); // The pseudo instruction is gone now.
4852 
4853   return BB;
4854 }
4855 
4856 MachineBasicBlock *
emitPseudoD_SELECT(MachineInstr & MI,MachineBasicBlock * BB) const4857 MipsTargetLowering::emitPseudoD_SELECT(MachineInstr &MI,
4858                                        MachineBasicBlock *BB) const {
4859   assert(!(Subtarget.hasMips4() || Subtarget.hasMips32()) &&
4860          "Subtarget already supports SELECT nodes with the use of"
4861          "conditional-move instructions.");
4862 
4863   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
4864   DebugLoc DL = MI.getDebugLoc();
4865 
4866   // D_SELECT substitutes two SELECT nodes that goes one after another and
4867   // have the same condition operand. On machines which don't have
4868   // conditional-move instruction, it reduces unnecessary branch instructions
4869   // which are result of using two diamond patterns that are result of two
4870   // SELECT pseudo instructions.
4871   const BasicBlock *LLVM_BB = BB->getBasicBlock();
4872   MachineFunction::iterator It = ++BB->getIterator();
4873 
4874   //  thisMBB:
4875   //  ...
4876   //   TrueVal = ...
4877   //   setcc r1, r2, r3
4878   //   bNE   r1, r0, copy1MBB
4879   //   fallthrough --> copy0MBB
4880   MachineBasicBlock *thisMBB = BB;
4881   MachineFunction *F = BB->getParent();
4882   MachineBasicBlock *copy0MBB = F->CreateMachineBasicBlock(LLVM_BB);
4883   MachineBasicBlock *sinkMBB = F->CreateMachineBasicBlock(LLVM_BB);
4884   F->insert(It, copy0MBB);
4885   F->insert(It, sinkMBB);
4886 
4887   // Transfer the remainder of BB and its successor edges to sinkMBB.
4888   sinkMBB->splice(sinkMBB->begin(), BB,
4889                   std::next(MachineBasicBlock::iterator(MI)), BB->end());
4890   sinkMBB->transferSuccessorsAndUpdatePHIs(BB);
4891 
4892   // Next, add the true and fallthrough blocks as its successors.
4893   BB->addSuccessor(copy0MBB);
4894   BB->addSuccessor(sinkMBB);
4895 
4896   // bne rs, $0, sinkMBB
4897   BuildMI(BB, DL, TII->get(Mips::BNE))
4898       .addReg(MI.getOperand(2).getReg())
4899       .addReg(Mips::ZERO)
4900       .addMBB(sinkMBB);
4901 
4902   //  copy0MBB:
4903   //   %FalseValue = ...
4904   //   # fallthrough to sinkMBB
4905   BB = copy0MBB;
4906 
4907   // Update machine-CFG edges
4908   BB->addSuccessor(sinkMBB);
4909 
4910   //  sinkMBB:
4911   //   %Result = phi [ %TrueValue, thisMBB ], [ %FalseValue, copy0MBB ]
4912   //  ...
4913   BB = sinkMBB;
4914 
4915   // Use two PHI nodes to select two reults
4916   BuildMI(*BB, BB->begin(), DL, TII->get(Mips::PHI), MI.getOperand(0).getReg())
4917       .addReg(MI.getOperand(3).getReg())
4918       .addMBB(thisMBB)
4919       .addReg(MI.getOperand(5).getReg())
4920       .addMBB(copy0MBB);
4921   BuildMI(*BB, BB->begin(), DL, TII->get(Mips::PHI), MI.getOperand(1).getReg())
4922       .addReg(MI.getOperand(4).getReg())
4923       .addMBB(thisMBB)
4924       .addReg(MI.getOperand(6).getReg())
4925       .addMBB(copy0MBB);
4926 
4927   MI.eraseFromParent(); // The pseudo instruction is gone now.
4928 
4929   return BB;
4930 }
4931 
4932 // FIXME? Maybe this could be a TableGen attribute on some registers and
4933 // this table could be generated automatically from RegInfo.
4934 Register
getRegisterByName(const char * RegName,LLT VT,const MachineFunction & MF) const4935 MipsTargetLowering::getRegisterByName(const char *RegName, LLT VT,
4936                                       const MachineFunction &MF) const {
4937   // The Linux kernel uses $28 and sp.
4938   if (Subtarget.isGP64bit()) {
4939     Register Reg = StringSwitch<Register>(RegName)
4940                        .Case("$28", Mips::GP_64)
4941                        .Case("sp", Mips::SP_64)
4942                        .Default(Register());
4943     return Reg;
4944   }
4945 
4946   Register Reg = StringSwitch<Register>(RegName)
4947                      .Case("$28", Mips::GP)
4948                      .Case("sp", Mips::SP)
4949                      .Default(Register());
4950   return Reg;
4951 }
4952 
emitLDR_W(MachineInstr & MI,MachineBasicBlock * BB) const4953 MachineBasicBlock *MipsTargetLowering::emitLDR_W(MachineInstr &MI,
4954                                                  MachineBasicBlock *BB) const {
4955   MachineFunction *MF = BB->getParent();
4956   MachineRegisterInfo &MRI = MF->getRegInfo();
4957   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
4958   const bool IsLittle = Subtarget.isLittle();
4959   DebugLoc DL = MI.getDebugLoc();
4960 
4961   Register Dest = MI.getOperand(0).getReg();
4962   Register Address = MI.getOperand(1).getReg();
4963   unsigned Imm = MI.getOperand(2).getImm();
4964 
4965   MachineBasicBlock::iterator I(MI);
4966 
4967   if (Subtarget.hasMips32r6() || Subtarget.hasMips64r6()) {
4968     // Mips release 6 can load from adress that is not naturally-aligned.
4969     Register Temp = MRI.createVirtualRegister(&Mips::GPR32RegClass);
4970     BuildMI(*BB, I, DL, TII->get(Mips::LW))
4971         .addDef(Temp)
4972         .addUse(Address)
4973         .addImm(Imm);
4974     BuildMI(*BB, I, DL, TII->get(Mips::FILL_W)).addDef(Dest).addUse(Temp);
4975   } else {
4976     // Mips release 5 needs to use instructions that can load from an unaligned
4977     // memory address.
4978     Register LoadHalf = MRI.createVirtualRegister(&Mips::GPR32RegClass);
4979     Register LoadFull = MRI.createVirtualRegister(&Mips::GPR32RegClass);
4980     Register Undef = MRI.createVirtualRegister(&Mips::GPR32RegClass);
4981     BuildMI(*BB, I, DL, TII->get(Mips::IMPLICIT_DEF)).addDef(Undef);
4982     BuildMI(*BB, I, DL, TII->get(Mips::LWR))
4983         .addDef(LoadHalf)
4984         .addUse(Address)
4985         .addImm(Imm + (IsLittle ? 0 : 3))
4986         .addUse(Undef);
4987     BuildMI(*BB, I, DL, TII->get(Mips::LWL))
4988         .addDef(LoadFull)
4989         .addUse(Address)
4990         .addImm(Imm + (IsLittle ? 3 : 0))
4991         .addUse(LoadHalf);
4992     BuildMI(*BB, I, DL, TII->get(Mips::FILL_W)).addDef(Dest).addUse(LoadFull);
4993   }
4994 
4995   MI.eraseFromParent();
4996   return BB;
4997 }
4998 
emitLDR_D(MachineInstr & MI,MachineBasicBlock * BB) const4999 MachineBasicBlock *MipsTargetLowering::emitLDR_D(MachineInstr &MI,
5000                                                  MachineBasicBlock *BB) const {
5001   MachineFunction *MF = BB->getParent();
5002   MachineRegisterInfo &MRI = MF->getRegInfo();
5003   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
5004   const bool IsLittle = Subtarget.isLittle();
5005   DebugLoc DL = MI.getDebugLoc();
5006 
5007   Register Dest = MI.getOperand(0).getReg();
5008   Register Address = MI.getOperand(1).getReg();
5009   unsigned Imm = MI.getOperand(2).getImm();
5010 
5011   MachineBasicBlock::iterator I(MI);
5012 
5013   if (Subtarget.hasMips32r6() || Subtarget.hasMips64r6()) {
5014     // Mips release 6 can load from adress that is not naturally-aligned.
5015     if (Subtarget.isGP64bit()) {
5016       Register Temp = MRI.createVirtualRegister(&Mips::GPR64RegClass);
5017       BuildMI(*BB, I, DL, TII->get(Mips::LD))
5018           .addDef(Temp)
5019           .addUse(Address)
5020           .addImm(Imm);
5021       BuildMI(*BB, I, DL, TII->get(Mips::FILL_D)).addDef(Dest).addUse(Temp);
5022     } else {
5023       Register Wtemp = MRI.createVirtualRegister(&Mips::MSA128WRegClass);
5024       Register Lo = MRI.createVirtualRegister(&Mips::GPR32RegClass);
5025       Register Hi = MRI.createVirtualRegister(&Mips::GPR32RegClass);
5026       BuildMI(*BB, I, DL, TII->get(Mips::LW))
5027           .addDef(Lo)
5028           .addUse(Address)
5029           .addImm(Imm + (IsLittle ? 0 : 4));
5030       BuildMI(*BB, I, DL, TII->get(Mips::LW))
5031           .addDef(Hi)
5032           .addUse(Address)
5033           .addImm(Imm + (IsLittle ? 4 : 0));
5034       BuildMI(*BB, I, DL, TII->get(Mips::FILL_W)).addDef(Wtemp).addUse(Lo);
5035       BuildMI(*BB, I, DL, TII->get(Mips::INSERT_W), Dest)
5036           .addUse(Wtemp)
5037           .addUse(Hi)
5038           .addImm(1);
5039     }
5040   } else {
5041     // Mips release 5 needs to use instructions that can load from an unaligned
5042     // memory address.
5043     Register LoHalf = MRI.createVirtualRegister(&Mips::GPR32RegClass);
5044     Register LoFull = MRI.createVirtualRegister(&Mips::GPR32RegClass);
5045     Register LoUndef = MRI.createVirtualRegister(&Mips::GPR32RegClass);
5046     Register HiHalf = MRI.createVirtualRegister(&Mips::GPR32RegClass);
5047     Register HiFull = MRI.createVirtualRegister(&Mips::GPR32RegClass);
5048     Register HiUndef = MRI.createVirtualRegister(&Mips::GPR32RegClass);
5049     Register Wtemp = MRI.createVirtualRegister(&Mips::MSA128WRegClass);
5050     BuildMI(*BB, I, DL, TII->get(Mips::IMPLICIT_DEF)).addDef(LoUndef);
5051     BuildMI(*BB, I, DL, TII->get(Mips::LWR))
5052         .addDef(LoHalf)
5053         .addUse(Address)
5054         .addImm(Imm + (IsLittle ? 0 : 7))
5055         .addUse(LoUndef);
5056     BuildMI(*BB, I, DL, TII->get(Mips::LWL))
5057         .addDef(LoFull)
5058         .addUse(Address)
5059         .addImm(Imm + (IsLittle ? 3 : 4))
5060         .addUse(LoHalf);
5061     BuildMI(*BB, I, DL, TII->get(Mips::IMPLICIT_DEF)).addDef(HiUndef);
5062     BuildMI(*BB, I, DL, TII->get(Mips::LWR))
5063         .addDef(HiHalf)
5064         .addUse(Address)
5065         .addImm(Imm + (IsLittle ? 4 : 3))
5066         .addUse(HiUndef);
5067     BuildMI(*BB, I, DL, TII->get(Mips::LWL))
5068         .addDef(HiFull)
5069         .addUse(Address)
5070         .addImm(Imm + (IsLittle ? 7 : 0))
5071         .addUse(HiHalf);
5072     BuildMI(*BB, I, DL, TII->get(Mips::FILL_W)).addDef(Wtemp).addUse(LoFull);
5073     BuildMI(*BB, I, DL, TII->get(Mips::INSERT_W), Dest)
5074         .addUse(Wtemp)
5075         .addUse(HiFull)
5076         .addImm(1);
5077   }
5078 
5079   MI.eraseFromParent();
5080   return BB;
5081 }
5082 
emitSTR_W(MachineInstr & MI,MachineBasicBlock * BB) const5083 MachineBasicBlock *MipsTargetLowering::emitSTR_W(MachineInstr &MI,
5084                                                  MachineBasicBlock *BB) const {
5085   MachineFunction *MF = BB->getParent();
5086   MachineRegisterInfo &MRI = MF->getRegInfo();
5087   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
5088   const bool IsLittle = Subtarget.isLittle();
5089   DebugLoc DL = MI.getDebugLoc();
5090 
5091   Register StoreVal = MI.getOperand(0).getReg();
5092   Register Address = MI.getOperand(1).getReg();
5093   unsigned Imm = MI.getOperand(2).getImm();
5094 
5095   MachineBasicBlock::iterator I(MI);
5096 
5097   if (Subtarget.hasMips32r6() || Subtarget.hasMips64r6()) {
5098     // Mips release 6 can store to adress that is not naturally-aligned.
5099     Register BitcastW = MRI.createVirtualRegister(&Mips::MSA128WRegClass);
5100     Register Tmp = MRI.createVirtualRegister(&Mips::GPR32RegClass);
5101     BuildMI(*BB, I, DL, TII->get(Mips::COPY)).addDef(BitcastW).addUse(StoreVal);
5102     BuildMI(*BB, I, DL, TII->get(Mips::COPY_S_W))
5103         .addDef(Tmp)
5104         .addUse(BitcastW)
5105         .addImm(0);
5106     BuildMI(*BB, I, DL, TII->get(Mips::SW))
5107         .addUse(Tmp)
5108         .addUse(Address)
5109         .addImm(Imm);
5110   } else {
5111     // Mips release 5 needs to use instructions that can store to an unaligned
5112     // memory address.
5113     Register Tmp = MRI.createVirtualRegister(&Mips::GPR32RegClass);
5114     BuildMI(*BB, I, DL, TII->get(Mips::COPY_S_W))
5115         .addDef(Tmp)
5116         .addUse(StoreVal)
5117         .addImm(0);
5118     BuildMI(*BB, I, DL, TII->get(Mips::SWR))
5119         .addUse(Tmp)
5120         .addUse(Address)
5121         .addImm(Imm + (IsLittle ? 0 : 3));
5122     BuildMI(*BB, I, DL, TII->get(Mips::SWL))
5123         .addUse(Tmp)
5124         .addUse(Address)
5125         .addImm(Imm + (IsLittle ? 3 : 0));
5126   }
5127 
5128   MI.eraseFromParent();
5129 
5130   return BB;
5131 }
5132 
emitSTR_D(MachineInstr & MI,MachineBasicBlock * BB) const5133 MachineBasicBlock *MipsTargetLowering::emitSTR_D(MachineInstr &MI,
5134                                                  MachineBasicBlock *BB) const {
5135   MachineFunction *MF = BB->getParent();
5136   MachineRegisterInfo &MRI = MF->getRegInfo();
5137   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
5138   const bool IsLittle = Subtarget.isLittle();
5139   DebugLoc DL = MI.getDebugLoc();
5140 
5141   Register StoreVal = MI.getOperand(0).getReg();
5142   Register Address = MI.getOperand(1).getReg();
5143   unsigned Imm = MI.getOperand(2).getImm();
5144 
5145   MachineBasicBlock::iterator I(MI);
5146 
5147   if (Subtarget.hasMips32r6() || Subtarget.hasMips64r6()) {
5148     // Mips release 6 can store to adress that is not naturally-aligned.
5149     if (Subtarget.isGP64bit()) {
5150       Register BitcastD = MRI.createVirtualRegister(&Mips::MSA128DRegClass);
5151       Register Lo = MRI.createVirtualRegister(&Mips::GPR64RegClass);
5152       BuildMI(*BB, I, DL, TII->get(Mips::COPY))
5153           .addDef(BitcastD)
5154           .addUse(StoreVal);
5155       BuildMI(*BB, I, DL, TII->get(Mips::COPY_S_D))
5156           .addDef(Lo)
5157           .addUse(BitcastD)
5158           .addImm(0);
5159       BuildMI(*BB, I, DL, TII->get(Mips::SD))
5160           .addUse(Lo)
5161           .addUse(Address)
5162           .addImm(Imm);
5163     } else {
5164       Register BitcastW = MRI.createVirtualRegister(&Mips::MSA128WRegClass);
5165       Register Lo = MRI.createVirtualRegister(&Mips::GPR32RegClass);
5166       Register Hi = MRI.createVirtualRegister(&Mips::GPR32RegClass);
5167       BuildMI(*BB, I, DL, TII->get(Mips::COPY))
5168           .addDef(BitcastW)
5169           .addUse(StoreVal);
5170       BuildMI(*BB, I, DL, TII->get(Mips::COPY_S_W))
5171           .addDef(Lo)
5172           .addUse(BitcastW)
5173           .addImm(0);
5174       BuildMI(*BB, I, DL, TII->get(Mips::COPY_S_W))
5175           .addDef(Hi)
5176           .addUse(BitcastW)
5177           .addImm(1);
5178       BuildMI(*BB, I, DL, TII->get(Mips::SW))
5179           .addUse(Lo)
5180           .addUse(Address)
5181           .addImm(Imm + (IsLittle ? 0 : 4));
5182       BuildMI(*BB, I, DL, TII->get(Mips::SW))
5183           .addUse(Hi)
5184           .addUse(Address)
5185           .addImm(Imm + (IsLittle ? 4 : 0));
5186     }
5187   } else {
5188     // Mips release 5 needs to use instructions that can store to an unaligned
5189     // memory address.
5190     Register Bitcast = MRI.createVirtualRegister(&Mips::MSA128WRegClass);
5191     Register Lo = MRI.createVirtualRegister(&Mips::GPR32RegClass);
5192     Register Hi = MRI.createVirtualRegister(&Mips::GPR32RegClass);
5193     BuildMI(*BB, I, DL, TII->get(Mips::COPY)).addDef(Bitcast).addUse(StoreVal);
5194     BuildMI(*BB, I, DL, TII->get(Mips::COPY_S_W))
5195         .addDef(Lo)
5196         .addUse(Bitcast)
5197         .addImm(0);
5198     BuildMI(*BB, I, DL, TII->get(Mips::COPY_S_W))
5199         .addDef(Hi)
5200         .addUse(Bitcast)
5201         .addImm(1);
5202     BuildMI(*BB, I, DL, TII->get(Mips::SWR))
5203         .addUse(Lo)
5204         .addUse(Address)
5205         .addImm(Imm + (IsLittle ? 0 : 3));
5206     BuildMI(*BB, I, DL, TII->get(Mips::SWL))
5207         .addUse(Lo)
5208         .addUse(Address)
5209         .addImm(Imm + (IsLittle ? 3 : 0));
5210     BuildMI(*BB, I, DL, TII->get(Mips::SWR))
5211         .addUse(Hi)
5212         .addUse(Address)
5213         .addImm(Imm + (IsLittle ? 4 : 7));
5214     BuildMI(*BB, I, DL, TII->get(Mips::SWL))
5215         .addUse(Hi)
5216         .addUse(Address)
5217         .addImm(Imm + (IsLittle ? 7 : 4));
5218   }
5219 
5220   MI.eraseFromParent();
5221   return BB;
5222 }
5223