xref: /freebsd/contrib/llvm-project/llvm/lib/Target/Mips/MipsISelLowering.cpp (revision 0fca6ea1d4eea4c934cfff25ac9ee8ad6fe95583)
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/RuntimeLibcallUtil.h"
44 #include "llvm/CodeGen/SelectionDAG.h"
45 #include "llvm/CodeGen/SelectionDAGNodes.h"
46 #include "llvm/CodeGen/TargetFrameLowering.h"
47 #include "llvm/CodeGen/TargetInstrInfo.h"
48 #include "llvm/CodeGen/TargetRegisterInfo.h"
49 #include "llvm/CodeGen/ValueTypes.h"
50 #include "llvm/CodeGenTypes/MachineValueType.h"
51 #include "llvm/IR/CallingConv.h"
52 #include "llvm/IR/Constants.h"
53 #include "llvm/IR/DataLayout.h"
54 #include "llvm/IR/DebugLoc.h"
55 #include "llvm/IR/DerivedTypes.h"
56 #include "llvm/IR/Function.h"
57 #include "llvm/IR/GlobalValue.h"
58 #include "llvm/IR/Module.h"
59 #include "llvm/IR/Type.h"
60 #include "llvm/IR/Value.h"
61 #include "llvm/MC/MCContext.h"
62 #include "llvm/MC/MCRegisterInfo.h"
63 #include "llvm/Support/Casting.h"
64 #include "llvm/Support/CodeGen.h"
65 #include "llvm/Support/CommandLine.h"
66 #include "llvm/Support/Compiler.h"
67 #include "llvm/Support/ErrorHandling.h"
68 #include "llvm/Support/MathExtras.h"
69 #include "llvm/Target/TargetMachine.h"
70 #include "llvm/Target/TargetOptions.h"
71 #include <algorithm>
72 #include <cassert>
73 #include <cctype>
74 #include <cstdint>
75 #include <deque>
76 #include <iterator>
77 #include <utility>
78 #include <vector>
79 
80 using namespace llvm;
81 
82 #define DEBUG_TYPE "mips-lower"
83 
84 STATISTIC(NumTailCalls, "Number of tail calls");
85 
86 static cl::opt<bool>
87 NoZeroDivCheck("mno-check-zero-division", cl::Hidden,
88                cl::desc("MIPS: Don't trap on integer division by zero."),
89                cl::init(false));
90 
91 extern cl::opt<bool> EmitJalrReloc;
92 
93 static const MCPhysReg Mips64DPRegs[8] = {
94   Mips::D12_64, Mips::D13_64, Mips::D14_64, Mips::D15_64,
95   Mips::D16_64, Mips::D17_64, Mips::D18_64, Mips::D19_64
96 };
97 
98 // The MIPS MSA ABI passes vector arguments in the integer register set.
99 // The number of integer registers used is dependant on the ABI used.
getRegisterTypeForCallingConv(LLVMContext & Context,CallingConv::ID CC,EVT VT) const100 MVT MipsTargetLowering::getRegisterTypeForCallingConv(LLVMContext &Context,
101                                                       CallingConv::ID CC,
102                                                       EVT VT) const {
103   if (!VT.isVector())
104     return getRegisterType(Context, VT);
105 
106   if (VT.isPow2VectorType() && VT.getVectorElementType().isRound())
107     return Subtarget.isABI_O32() || VT.getSizeInBits() == 32 ? MVT::i32
108                                                              : MVT::i64;
109   return getRegisterType(Context, VT.getVectorElementType());
110 }
111 
getNumRegistersForCallingConv(LLVMContext & Context,CallingConv::ID CC,EVT VT) const112 unsigned MipsTargetLowering::getNumRegistersForCallingConv(LLVMContext &Context,
113                                                            CallingConv::ID CC,
114                                                            EVT VT) const {
115   if (VT.isVector()) {
116     if (VT.isPow2VectorType() && VT.getVectorElementType().isRound())
117       return divideCeil(VT.getSizeInBits(), Subtarget.isABI_O32() ? 32 : 64);
118     return VT.getVectorNumElements() *
119            getNumRegisters(Context, VT.getVectorElementType());
120   }
121   return MipsTargetLowering::getNumRegisters(Context, VT);
122 }
123 
getVectorTypeBreakdownForCallingConv(LLVMContext & Context,CallingConv::ID CC,EVT VT,EVT & IntermediateVT,unsigned & NumIntermediates,MVT & RegisterVT) const124 unsigned MipsTargetLowering::getVectorTypeBreakdownForCallingConv(
125     LLVMContext &Context, CallingConv::ID CC, EVT VT, EVT &IntermediateVT,
126     unsigned &NumIntermediates, MVT &RegisterVT) const {
127   if (VT.isPow2VectorType()) {
128     IntermediateVT = getRegisterTypeForCallingConv(Context, CC, VT);
129     RegisterVT = IntermediateVT.getSimpleVT();
130     NumIntermediates = getNumRegistersForCallingConv(Context, CC, VT);
131     return NumIntermediates;
132   }
133   IntermediateVT = VT.getVectorElementType();
134   NumIntermediates = VT.getVectorNumElements();
135   RegisterVT = getRegisterType(Context, IntermediateVT);
136   return NumIntermediates * getNumRegisters(Context, IntermediateVT);
137 }
138 
getGlobalReg(SelectionDAG & DAG,EVT Ty) const139 SDValue MipsTargetLowering::getGlobalReg(SelectionDAG &DAG, EVT Ty) const {
140   MachineFunction &MF = DAG.getMachineFunction();
141   MipsFunctionInfo *FI = MF.getInfo<MipsFunctionInfo>();
142   return DAG.getRegister(FI->getGlobalBaseReg(MF), Ty);
143 }
144 
getTargetNode(GlobalAddressSDNode * N,EVT Ty,SelectionDAG & DAG,unsigned Flag) const145 SDValue MipsTargetLowering::getTargetNode(GlobalAddressSDNode *N, EVT Ty,
146                                           SelectionDAG &DAG,
147                                           unsigned Flag) const {
148   return DAG.getTargetGlobalAddress(N->getGlobal(), SDLoc(N), Ty, 0, Flag);
149 }
150 
getTargetNode(ExternalSymbolSDNode * N,EVT Ty,SelectionDAG & DAG,unsigned Flag) const151 SDValue MipsTargetLowering::getTargetNode(ExternalSymbolSDNode *N, EVT Ty,
152                                           SelectionDAG &DAG,
153                                           unsigned Flag) const {
154   return DAG.getTargetExternalSymbol(N->getSymbol(), Ty, Flag);
155 }
156 
getTargetNode(BlockAddressSDNode * N,EVT Ty,SelectionDAG & DAG,unsigned Flag) const157 SDValue MipsTargetLowering::getTargetNode(BlockAddressSDNode *N, EVT Ty,
158                                           SelectionDAG &DAG,
159                                           unsigned Flag) const {
160   return DAG.getTargetBlockAddress(N->getBlockAddress(), Ty, 0, Flag);
161 }
162 
getTargetNode(JumpTableSDNode * N,EVT Ty,SelectionDAG & DAG,unsigned Flag) const163 SDValue MipsTargetLowering::getTargetNode(JumpTableSDNode *N, EVT Ty,
164                                           SelectionDAG &DAG,
165                                           unsigned Flag) const {
166   return DAG.getTargetJumpTable(N->getIndex(), Ty, Flag);
167 }
168 
getTargetNode(ConstantPoolSDNode * N,EVT Ty,SelectionDAG & DAG,unsigned Flag) const169 SDValue MipsTargetLowering::getTargetNode(ConstantPoolSDNode *N, EVT Ty,
170                                           SelectionDAG &DAG,
171                                           unsigned Flag) const {
172   return DAG.getTargetConstantPool(N->getConstVal(), Ty, N->getAlign(),
173                                    N->getOffset(), Flag);
174 }
175 
getTargetNodeName(unsigned Opcode) const176 const char *MipsTargetLowering::getTargetNodeName(unsigned Opcode) const {
177   switch ((MipsISD::NodeType)Opcode) {
178   case MipsISD::FIRST_NUMBER:      break;
179   case MipsISD::JmpLink:           return "MipsISD::JmpLink";
180   case MipsISD::TailCall:          return "MipsISD::TailCall";
181   case MipsISD::Highest:           return "MipsISD::Highest";
182   case MipsISD::Higher:            return "MipsISD::Higher";
183   case MipsISD::Hi:                return "MipsISD::Hi";
184   case MipsISD::Lo:                return "MipsISD::Lo";
185   case MipsISD::GotHi:             return "MipsISD::GotHi";
186   case MipsISD::TlsHi:             return "MipsISD::TlsHi";
187   case MipsISD::GPRel:             return "MipsISD::GPRel";
188   case MipsISD::ThreadPointer:     return "MipsISD::ThreadPointer";
189   case MipsISD::Ret:               return "MipsISD::Ret";
190   case MipsISD::ERet:              return "MipsISD::ERet";
191   case MipsISD::EH_RETURN:         return "MipsISD::EH_RETURN";
192   case MipsISD::FAbs:              return "MipsISD::FAbs";
193   case MipsISD::FMS:               return "MipsISD::FMS";
194   case MipsISD::FPBrcond:          return "MipsISD::FPBrcond";
195   case MipsISD::FPCmp:             return "MipsISD::FPCmp";
196   case MipsISD::FSELECT:           return "MipsISD::FSELECT";
197   case MipsISD::MTC1_D64:          return "MipsISD::MTC1_D64";
198   case MipsISD::CMovFP_T:          return "MipsISD::CMovFP_T";
199   case MipsISD::CMovFP_F:          return "MipsISD::CMovFP_F";
200   case MipsISD::TruncIntFP:        return "MipsISD::TruncIntFP";
201   case MipsISD::MFHI:              return "MipsISD::MFHI";
202   case MipsISD::MFLO:              return "MipsISD::MFLO";
203   case MipsISD::MTLOHI:            return "MipsISD::MTLOHI";
204   case MipsISD::Mult:              return "MipsISD::Mult";
205   case MipsISD::Multu:             return "MipsISD::Multu";
206   case MipsISD::MAdd:              return "MipsISD::MAdd";
207   case MipsISD::MAddu:             return "MipsISD::MAddu";
208   case MipsISD::MSub:              return "MipsISD::MSub";
209   case MipsISD::MSubu:             return "MipsISD::MSubu";
210   case MipsISD::DivRem:            return "MipsISD::DivRem";
211   case MipsISD::DivRemU:           return "MipsISD::DivRemU";
212   case MipsISD::DivRem16:          return "MipsISD::DivRem16";
213   case MipsISD::DivRemU16:         return "MipsISD::DivRemU16";
214   case MipsISD::BuildPairF64:      return "MipsISD::BuildPairF64";
215   case MipsISD::ExtractElementF64: return "MipsISD::ExtractElementF64";
216   case MipsISD::Wrapper:           return "MipsISD::Wrapper";
217   case MipsISD::DynAlloc:          return "MipsISD::DynAlloc";
218   case MipsISD::Sync:              return "MipsISD::Sync";
219   case MipsISD::Ext:               return "MipsISD::Ext";
220   case MipsISD::Ins:               return "MipsISD::Ins";
221   case MipsISD::CIns:              return "MipsISD::CIns";
222   case MipsISD::LWL:               return "MipsISD::LWL";
223   case MipsISD::LWR:               return "MipsISD::LWR";
224   case MipsISD::SWL:               return "MipsISD::SWL";
225   case MipsISD::SWR:               return "MipsISD::SWR";
226   case MipsISD::LDL:               return "MipsISD::LDL";
227   case MipsISD::LDR:               return "MipsISD::LDR";
228   case MipsISD::SDL:               return "MipsISD::SDL";
229   case MipsISD::SDR:               return "MipsISD::SDR";
230   case MipsISD::EXTP:              return "MipsISD::EXTP";
231   case MipsISD::EXTPDP:            return "MipsISD::EXTPDP";
232   case MipsISD::EXTR_S_H:          return "MipsISD::EXTR_S_H";
233   case MipsISD::EXTR_W:            return "MipsISD::EXTR_W";
234   case MipsISD::EXTR_R_W:          return "MipsISD::EXTR_R_W";
235   case MipsISD::EXTR_RS_W:         return "MipsISD::EXTR_RS_W";
236   case MipsISD::SHILO:             return "MipsISD::SHILO";
237   case MipsISD::MTHLIP:            return "MipsISD::MTHLIP";
238   case MipsISD::MULSAQ_S_W_PH:     return "MipsISD::MULSAQ_S_W_PH";
239   case MipsISD::MAQ_S_W_PHL:       return "MipsISD::MAQ_S_W_PHL";
240   case MipsISD::MAQ_S_W_PHR:       return "MipsISD::MAQ_S_W_PHR";
241   case MipsISD::MAQ_SA_W_PHL:      return "MipsISD::MAQ_SA_W_PHL";
242   case MipsISD::MAQ_SA_W_PHR:      return "MipsISD::MAQ_SA_W_PHR";
243   case MipsISD::DOUBLE_SELECT_I:   return "MipsISD::DOUBLE_SELECT_I";
244   case MipsISD::DOUBLE_SELECT_I64: return "MipsISD::DOUBLE_SELECT_I64";
245   case MipsISD::DPAU_H_QBL:        return "MipsISD::DPAU_H_QBL";
246   case MipsISD::DPAU_H_QBR:        return "MipsISD::DPAU_H_QBR";
247   case MipsISD::DPSU_H_QBL:        return "MipsISD::DPSU_H_QBL";
248   case MipsISD::DPSU_H_QBR:        return "MipsISD::DPSU_H_QBR";
249   case MipsISD::DPAQ_S_W_PH:       return "MipsISD::DPAQ_S_W_PH";
250   case MipsISD::DPSQ_S_W_PH:       return "MipsISD::DPSQ_S_W_PH";
251   case MipsISD::DPAQ_SA_L_W:       return "MipsISD::DPAQ_SA_L_W";
252   case MipsISD::DPSQ_SA_L_W:       return "MipsISD::DPSQ_SA_L_W";
253   case MipsISD::DPA_W_PH:          return "MipsISD::DPA_W_PH";
254   case MipsISD::DPS_W_PH:          return "MipsISD::DPS_W_PH";
255   case MipsISD::DPAQX_S_W_PH:      return "MipsISD::DPAQX_S_W_PH";
256   case MipsISD::DPAQX_SA_W_PH:     return "MipsISD::DPAQX_SA_W_PH";
257   case MipsISD::DPAX_W_PH:         return "MipsISD::DPAX_W_PH";
258   case MipsISD::DPSX_W_PH:         return "MipsISD::DPSX_W_PH";
259   case MipsISD::DPSQX_S_W_PH:      return "MipsISD::DPSQX_S_W_PH";
260   case MipsISD::DPSQX_SA_W_PH:     return "MipsISD::DPSQX_SA_W_PH";
261   case MipsISD::MULSA_W_PH:        return "MipsISD::MULSA_W_PH";
262   case MipsISD::MULT:              return "MipsISD::MULT";
263   case MipsISD::MULTU:             return "MipsISD::MULTU";
264   case MipsISD::MADD_DSP:          return "MipsISD::MADD_DSP";
265   case MipsISD::MADDU_DSP:         return "MipsISD::MADDU_DSP";
266   case MipsISD::MSUB_DSP:          return "MipsISD::MSUB_DSP";
267   case MipsISD::MSUBU_DSP:         return "MipsISD::MSUBU_DSP";
268   case MipsISD::SHLL_DSP:          return "MipsISD::SHLL_DSP";
269   case MipsISD::SHRA_DSP:          return "MipsISD::SHRA_DSP";
270   case MipsISD::SHRL_DSP:          return "MipsISD::SHRL_DSP";
271   case MipsISD::SETCC_DSP:         return "MipsISD::SETCC_DSP";
272   case MipsISD::SELECT_CC_DSP:     return "MipsISD::SELECT_CC_DSP";
273   case MipsISD::VALL_ZERO:         return "MipsISD::VALL_ZERO";
274   case MipsISD::VANY_ZERO:         return "MipsISD::VANY_ZERO";
275   case MipsISD::VALL_NONZERO:      return "MipsISD::VALL_NONZERO";
276   case MipsISD::VANY_NONZERO:      return "MipsISD::VANY_NONZERO";
277   case MipsISD::VCEQ:              return "MipsISD::VCEQ";
278   case MipsISD::VCLE_S:            return "MipsISD::VCLE_S";
279   case MipsISD::VCLE_U:            return "MipsISD::VCLE_U";
280   case MipsISD::VCLT_S:            return "MipsISD::VCLT_S";
281   case MipsISD::VCLT_U:            return "MipsISD::VCLT_U";
282   case MipsISD::VEXTRACT_SEXT_ELT: return "MipsISD::VEXTRACT_SEXT_ELT";
283   case MipsISD::VEXTRACT_ZEXT_ELT: return "MipsISD::VEXTRACT_ZEXT_ELT";
284   case MipsISD::VNOR:              return "MipsISD::VNOR";
285   case MipsISD::VSHF:              return "MipsISD::VSHF";
286   case MipsISD::SHF:               return "MipsISD::SHF";
287   case MipsISD::ILVEV:             return "MipsISD::ILVEV";
288   case MipsISD::ILVOD:             return "MipsISD::ILVOD";
289   case MipsISD::ILVL:              return "MipsISD::ILVL";
290   case MipsISD::ILVR:              return "MipsISD::ILVR";
291   case MipsISD::PCKEV:             return "MipsISD::PCKEV";
292   case MipsISD::PCKOD:             return "MipsISD::PCKOD";
293   case MipsISD::INSVE:             return "MipsISD::INSVE";
294   }
295   return nullptr;
296 }
297 
MipsTargetLowering(const MipsTargetMachine & TM,const MipsSubtarget & STI)298 MipsTargetLowering::MipsTargetLowering(const MipsTargetMachine &TM,
299                                        const MipsSubtarget &STI)
300     : TargetLowering(TM), Subtarget(STI), ABI(TM.getABI()) {
301   // Mips does not have i1 type, so use i32 for
302   // setcc operations results (slt, sgt, ...).
303   setBooleanContents(ZeroOrOneBooleanContent);
304   setBooleanVectorContents(ZeroOrNegativeOneBooleanContent);
305   // The cmp.cond.fmt instruction in MIPS32r6/MIPS64r6 uses 0 and -1 like MSA
306   // does. Integer booleans still use 0 and 1.
307   if (Subtarget.hasMips32r6())
308     setBooleanContents(ZeroOrOneBooleanContent,
309                        ZeroOrNegativeOneBooleanContent);
310 
311   // Load extented operations for i1 types must be promoted
312   for (MVT VT : MVT::integer_valuetypes()) {
313     setLoadExtAction(ISD::EXTLOAD,  VT, MVT::i1,  Promote);
314     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i1,  Promote);
315     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i1,  Promote);
316   }
317 
318   // MIPS doesn't have extending float->double load/store.  Set LoadExtAction
319   // for f32, f16
320   for (MVT VT : MVT::fp_valuetypes()) {
321     setLoadExtAction(ISD::EXTLOAD, VT, MVT::f32, Expand);
322     setLoadExtAction(ISD::EXTLOAD, VT, MVT::f16, Expand);
323   }
324 
325   // Set LoadExtAction for f16 vectors to Expand
326   for (MVT VT : MVT::fp_fixedlen_vector_valuetypes()) {
327     MVT F16VT = MVT::getVectorVT(MVT::f16, VT.getVectorNumElements());
328     if (F16VT.isValid())
329       setLoadExtAction(ISD::EXTLOAD, VT, F16VT, Expand);
330   }
331 
332   setTruncStoreAction(MVT::f32, MVT::f16, Expand);
333   setTruncStoreAction(MVT::f64, MVT::f16, Expand);
334 
335   setTruncStoreAction(MVT::f64, MVT::f32, Expand);
336 
337   // Used by legalize types to correctly generate the setcc result.
338   // Without this, every float setcc comes with a AND/OR with the result,
339   // we don't want this, since the fpcmp result goes to a flag register,
340   // which is used implicitly by brcond and select operations.
341   AddPromotedToType(ISD::SETCC, MVT::i1, MVT::i32);
342 
343   // Mips Custom Operations
344   setOperationAction(ISD::BR_JT,              MVT::Other, Expand);
345   setOperationAction(ISD::GlobalAddress,      MVT::i32,   Custom);
346   setOperationAction(ISD::BlockAddress,       MVT::i32,   Custom);
347   setOperationAction(ISD::GlobalTLSAddress,   MVT::i32,   Custom);
348   setOperationAction(ISD::JumpTable,          MVT::i32,   Custom);
349   setOperationAction(ISD::ConstantPool,       MVT::i32,   Custom);
350   setOperationAction(ISD::SELECT,             MVT::f32,   Custom);
351   setOperationAction(ISD::SELECT,             MVT::f64,   Custom);
352   setOperationAction(ISD::SELECT,             MVT::i32,   Custom);
353   setOperationAction(ISD::SETCC,              MVT::f32,   Custom);
354   setOperationAction(ISD::SETCC,              MVT::f64,   Custom);
355   setOperationAction(ISD::BRCOND,             MVT::Other, Custom);
356   setOperationAction(ISD::FABS,               MVT::f32,   Custom);
357   setOperationAction(ISD::FABS,               MVT::f64,   Custom);
358   setOperationAction(ISD::FCOPYSIGN,          MVT::f32,   Custom);
359   setOperationAction(ISD::FCOPYSIGN,          MVT::f64,   Custom);
360   setOperationAction(ISD::FP_TO_SINT,         MVT::i32,   Custom);
361 
362   // Lower fmin and fmax operations for MIPS R6.
363   // Instructions are defined but never used.
364   if (Subtarget.hasMips32r6()) {
365     setOperationAction(ISD::FMINNUM_IEEE, MVT::f32, Legal);
366     setOperationAction(ISD::FMAXNUM_IEEE, MVT::f32, Legal);
367     setOperationAction(ISD::FMINNUM, MVT::f32, Expand);
368     setOperationAction(ISD::FMAXNUM, MVT::f32, Expand);
369     setOperationAction(ISD::FMINNUM_IEEE, MVT::f64, Legal);
370     setOperationAction(ISD::FMAXNUM_IEEE, MVT::f64, Legal);
371     setOperationAction(ISD::FMINNUM, MVT::f64, Expand);
372     setOperationAction(ISD::FMAXNUM, MVT::f64, Expand);
373   }
374 
375   if (Subtarget.isGP64bit()) {
376     setOperationAction(ISD::GlobalAddress,      MVT::i64,   Custom);
377     setOperationAction(ISD::BlockAddress,       MVT::i64,   Custom);
378     setOperationAction(ISD::GlobalTLSAddress,   MVT::i64,   Custom);
379     setOperationAction(ISD::JumpTable,          MVT::i64,   Custom);
380     setOperationAction(ISD::ConstantPool,       MVT::i64,   Custom);
381     setOperationAction(ISD::SELECT,             MVT::i64,   Custom);
382     if (Subtarget.hasMips64r6()) {
383       setOperationAction(ISD::LOAD,               MVT::i64,   Legal);
384       setOperationAction(ISD::STORE,              MVT::i64,   Legal);
385     } else {
386       setOperationAction(ISD::LOAD,               MVT::i64,   Custom);
387       setOperationAction(ISD::STORE,              MVT::i64,   Custom);
388     }
389     setOperationAction(ISD::FP_TO_SINT,         MVT::i64,   Custom);
390     setOperationAction(ISD::SHL_PARTS,          MVT::i64,   Custom);
391     setOperationAction(ISD::SRA_PARTS,          MVT::i64,   Custom);
392     setOperationAction(ISD::SRL_PARTS,          MVT::i64,   Custom);
393   }
394 
395   if (!Subtarget.isGP64bit()) {
396     setOperationAction(ISD::SHL_PARTS,          MVT::i32,   Custom);
397     setOperationAction(ISD::SRA_PARTS,          MVT::i32,   Custom);
398     setOperationAction(ISD::SRL_PARTS,          MVT::i32,   Custom);
399   }
400 
401   setOperationAction(ISD::EH_DWARF_CFA,         MVT::i32,   Custom);
402   if (Subtarget.isGP64bit())
403     setOperationAction(ISD::EH_DWARF_CFA,       MVT::i64,   Custom);
404 
405   setOperationAction(ISD::SDIV, MVT::i32, Expand);
406   setOperationAction(ISD::SREM, MVT::i32, Expand);
407   setOperationAction(ISD::UDIV, MVT::i32, Expand);
408   setOperationAction(ISD::UREM, MVT::i32, Expand);
409   setOperationAction(ISD::SDIV, MVT::i64, Expand);
410   setOperationAction(ISD::SREM, MVT::i64, Expand);
411   setOperationAction(ISD::UDIV, MVT::i64, Expand);
412   setOperationAction(ISD::UREM, MVT::i64, Expand);
413 
414   // Operations not directly supported by Mips.
415   setOperationAction(ISD::BR_CC,             MVT::f32,   Expand);
416   setOperationAction(ISD::BR_CC,             MVT::f64,   Expand);
417   setOperationAction(ISD::BR_CC,             MVT::i32,   Expand);
418   setOperationAction(ISD::BR_CC,             MVT::i64,   Expand);
419   setOperationAction(ISD::SELECT_CC,         MVT::i32,   Expand);
420   setOperationAction(ISD::SELECT_CC,         MVT::i64,   Expand);
421   setOperationAction(ISD::SELECT_CC,         MVT::f32,   Expand);
422   setOperationAction(ISD::SELECT_CC,         MVT::f64,   Expand);
423   setOperationAction(ISD::UINT_TO_FP,        MVT::i32,   Expand);
424   setOperationAction(ISD::UINT_TO_FP,        MVT::i64,   Expand);
425   setOperationAction(ISD::FP_TO_UINT,        MVT::i32,   Expand);
426   setOperationAction(ISD::FP_TO_UINT,        MVT::i64,   Expand);
427   setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i1,    Expand);
428   if (Subtarget.hasCnMips()) {
429     setOperationAction(ISD::CTPOP,           MVT::i32,   Legal);
430     setOperationAction(ISD::CTPOP,           MVT::i64,   Legal);
431   } else {
432     setOperationAction(ISD::CTPOP,           MVT::i32,   Expand);
433     setOperationAction(ISD::CTPOP,           MVT::i64,   Expand);
434   }
435   setOperationAction(ISD::CTTZ,              MVT::i32,   Expand);
436   setOperationAction(ISD::CTTZ,              MVT::i64,   Expand);
437   setOperationAction(ISD::ROTL,              MVT::i32,   Expand);
438   setOperationAction(ISD::ROTL,              MVT::i64,   Expand);
439   setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32,  Expand);
440   setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i64,  Expand);
441 
442   if (!Subtarget.hasMips32r2())
443     setOperationAction(ISD::ROTR, MVT::i32,   Expand);
444 
445   if (!Subtarget.hasMips64r2())
446     setOperationAction(ISD::ROTR, MVT::i64,   Expand);
447 
448   setOperationAction(ISD::FSIN,              MVT::f32,   Expand);
449   setOperationAction(ISD::FSIN,              MVT::f64,   Expand);
450   setOperationAction(ISD::FCOS,              MVT::f32,   Expand);
451   setOperationAction(ISD::FCOS,              MVT::f64,   Expand);
452   setOperationAction(ISD::FSINCOS,           MVT::f32,   Expand);
453   setOperationAction(ISD::FSINCOS,           MVT::f64,   Expand);
454   setOperationAction(ISD::FPOW,              MVT::f32,   Expand);
455   setOperationAction(ISD::FPOW,              MVT::f64,   Expand);
456   setOperationAction(ISD::FLOG,              MVT::f32,   Expand);
457   setOperationAction(ISD::FLOG2,             MVT::f32,   Expand);
458   setOperationAction(ISD::FLOG10,            MVT::f32,   Expand);
459   setOperationAction(ISD::FEXP,              MVT::f32,   Expand);
460   setOperationAction(ISD::FMA,               MVT::f32,   Expand);
461   setOperationAction(ISD::FMA,               MVT::f64,   Expand);
462   setOperationAction(ISD::FREM,              MVT::f32,   Expand);
463   setOperationAction(ISD::FREM,              MVT::f64,   Expand);
464 
465   // Lower f16 conversion operations into library calls
466   setOperationAction(ISD::FP16_TO_FP,        MVT::f32,   Expand);
467   setOperationAction(ISD::FP_TO_FP16,        MVT::f32,   Expand);
468   setOperationAction(ISD::FP16_TO_FP,        MVT::f64,   Expand);
469   setOperationAction(ISD::FP_TO_FP16,        MVT::f64,   Expand);
470 
471   setOperationAction(ISD::EH_RETURN, MVT::Other, Custom);
472 
473   setOperationAction(ISD::VASTART,           MVT::Other, Custom);
474   setOperationAction(ISD::VAARG,             MVT::Other, Custom);
475   setOperationAction(ISD::VACOPY,            MVT::Other, Expand);
476   setOperationAction(ISD::VAEND,             MVT::Other, Expand);
477 
478   // Use the default for now
479   setOperationAction(ISD::STACKSAVE,         MVT::Other, Expand);
480   setOperationAction(ISD::STACKRESTORE,      MVT::Other, Expand);
481 
482   if (!Subtarget.isGP64bit()) {
483     setOperationAction(ISD::ATOMIC_LOAD,     MVT::i64,   Expand);
484     setOperationAction(ISD::ATOMIC_STORE,    MVT::i64,   Expand);
485   }
486 
487   if (!Subtarget.hasMips32r2()) {
488     setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i8,  Expand);
489     setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i16, Expand);
490   }
491 
492   // MIPS16 lacks MIPS32's clz and clo instructions.
493   if (!Subtarget.hasMips32() || Subtarget.inMips16Mode())
494     setOperationAction(ISD::CTLZ, MVT::i32, Expand);
495   if (!Subtarget.hasMips64())
496     setOperationAction(ISD::CTLZ, MVT::i64, Expand);
497 
498   if (!Subtarget.hasMips32r2())
499     setOperationAction(ISD::BSWAP, MVT::i32, Expand);
500   if (!Subtarget.hasMips64r2())
501     setOperationAction(ISD::BSWAP, MVT::i64, Expand);
502 
503   if (Subtarget.isGP64bit() && Subtarget.hasMips64r6()) {
504     setLoadExtAction(ISD::SEXTLOAD, MVT::i64, MVT::i32, Legal);
505     setLoadExtAction(ISD::ZEXTLOAD, MVT::i64, MVT::i32, Legal);
506     setLoadExtAction(ISD::EXTLOAD, MVT::i64, MVT::i32, Legal);
507     setTruncStoreAction(MVT::i64, MVT::i32, Legal);
508   } else if (Subtarget.isGP64bit()) {
509     setLoadExtAction(ISD::SEXTLOAD, MVT::i64, MVT::i32, Custom);
510     setLoadExtAction(ISD::ZEXTLOAD, MVT::i64, MVT::i32, Custom);
511     setLoadExtAction(ISD::EXTLOAD, MVT::i64, MVT::i32, Custom);
512     setTruncStoreAction(MVT::i64, MVT::i32, Custom);
513   }
514 
515   setOperationAction(ISD::TRAP, MVT::Other, Legal);
516 
517   setTargetDAGCombine({ISD::SDIVREM, ISD::UDIVREM, ISD::SELECT, ISD::AND,
518                        ISD::OR, ISD::ADD, ISD::SUB, ISD::AssertZext, ISD::SHL});
519 
520   if (Subtarget.isGP64bit())
521     setMaxAtomicSizeInBitsSupported(64);
522   else
523     setMaxAtomicSizeInBitsSupported(32);
524 
525   setMinFunctionAlignment(Subtarget.isGP64bit() ? Align(8) : Align(4));
526 
527   // The arguments on the stack are defined in terms of 4-byte slots on O32
528   // and 8-byte slots on N32/N64.
529   setMinStackArgumentAlignment((ABI.IsN32() || ABI.IsN64()) ? Align(8)
530                                                             : Align(4));
531 
532   setStackPointerRegisterToSaveRestore(ABI.IsN64() ? Mips::SP_64 : Mips::SP);
533 
534   MaxStoresPerMemcpy = 16;
535 
536   isMicroMips = Subtarget.inMicroMipsMode();
537 }
538 
539 const MipsTargetLowering *
create(const MipsTargetMachine & TM,const MipsSubtarget & STI)540 MipsTargetLowering::create(const MipsTargetMachine &TM,
541                            const MipsSubtarget &STI) {
542   if (STI.inMips16Mode())
543     return createMips16TargetLowering(TM, STI);
544 
545   return createMipsSETargetLowering(TM, STI);
546 }
547 
548 // Create a fast isel object.
549 FastISel *
createFastISel(FunctionLoweringInfo & funcInfo,const TargetLibraryInfo * libInfo) const550 MipsTargetLowering::createFastISel(FunctionLoweringInfo &funcInfo,
551                                   const TargetLibraryInfo *libInfo) const {
552   const MipsTargetMachine &TM =
553       static_cast<const MipsTargetMachine &>(funcInfo.MF->getTarget());
554 
555   // We support only the standard encoding [MIPS32,MIPS32R5] ISAs.
556   bool UseFastISel = TM.Options.EnableFastISel && Subtarget.hasMips32() &&
557                      !Subtarget.hasMips32r6() && !Subtarget.inMips16Mode() &&
558                      !Subtarget.inMicroMipsMode();
559 
560   // Disable if either of the following is true:
561   // We do not generate PIC, the ABI is not O32, XGOT is being used.
562   if (!TM.isPositionIndependent() || !TM.getABI().IsO32() ||
563       Subtarget.useXGOT())
564     UseFastISel = false;
565 
566   return UseFastISel ? Mips::createFastISel(funcInfo, libInfo) : nullptr;
567 }
568 
getSetCCResultType(const DataLayout &,LLVMContext &,EVT VT) const569 EVT MipsTargetLowering::getSetCCResultType(const DataLayout &, LLVMContext &,
570                                            EVT VT) const {
571   if (!VT.isVector())
572     return MVT::i32;
573   return VT.changeVectorElementTypeToInteger();
574 }
575 
performDivRemCombine(SDNode * N,SelectionDAG & DAG,TargetLowering::DAGCombinerInfo & DCI,const MipsSubtarget & Subtarget)576 static SDValue performDivRemCombine(SDNode *N, SelectionDAG &DAG,
577                                     TargetLowering::DAGCombinerInfo &DCI,
578                                     const MipsSubtarget &Subtarget) {
579   if (DCI.isBeforeLegalizeOps())
580     return SDValue();
581 
582   EVT Ty = N->getValueType(0);
583   unsigned LO = (Ty == MVT::i32) ? Mips::LO0 : Mips::LO0_64;
584   unsigned HI = (Ty == MVT::i32) ? Mips::HI0 : Mips::HI0_64;
585   unsigned Opc = N->getOpcode() == ISD::SDIVREM ? MipsISD::DivRem16 :
586                                                   MipsISD::DivRemU16;
587   SDLoc DL(N);
588 
589   SDValue DivRem = DAG.getNode(Opc, DL, MVT::Glue,
590                                N->getOperand(0), N->getOperand(1));
591   SDValue InChain = DAG.getEntryNode();
592   SDValue InGlue = DivRem;
593 
594   // insert MFLO
595   if (N->hasAnyUseOfValue(0)) {
596     SDValue CopyFromLo = DAG.getCopyFromReg(InChain, DL, LO, Ty,
597                                             InGlue);
598     DAG.ReplaceAllUsesOfValueWith(SDValue(N, 0), CopyFromLo);
599     InChain = CopyFromLo.getValue(1);
600     InGlue = CopyFromLo.getValue(2);
601   }
602 
603   // insert MFHI
604   if (N->hasAnyUseOfValue(1)) {
605     SDValue CopyFromHi = DAG.getCopyFromReg(InChain, DL,
606                                             HI, Ty, InGlue);
607     DAG.ReplaceAllUsesOfValueWith(SDValue(N, 1), CopyFromHi);
608   }
609 
610   return SDValue();
611 }
612 
condCodeToFCC(ISD::CondCode CC)613 static Mips::CondCode condCodeToFCC(ISD::CondCode CC) {
614   switch (CC) {
615   default: llvm_unreachable("Unknown fp condition code!");
616   case ISD::SETEQ:
617   case ISD::SETOEQ: return Mips::FCOND_OEQ;
618   case ISD::SETUNE: return Mips::FCOND_UNE;
619   case ISD::SETLT:
620   case ISD::SETOLT: return Mips::FCOND_OLT;
621   case ISD::SETGT:
622   case ISD::SETOGT: return Mips::FCOND_OGT;
623   case ISD::SETLE:
624   case ISD::SETOLE: return Mips::FCOND_OLE;
625   case ISD::SETGE:
626   case ISD::SETOGE: return Mips::FCOND_OGE;
627   case ISD::SETULT: return Mips::FCOND_ULT;
628   case ISD::SETULE: return Mips::FCOND_ULE;
629   case ISD::SETUGT: return Mips::FCOND_UGT;
630   case ISD::SETUGE: return Mips::FCOND_UGE;
631   case ISD::SETUO:  return Mips::FCOND_UN;
632   case ISD::SETO:   return Mips::FCOND_OR;
633   case ISD::SETNE:
634   case ISD::SETONE: return Mips::FCOND_ONE;
635   case ISD::SETUEQ: return Mips::FCOND_UEQ;
636   }
637 }
638 
639 /// This function returns true if the floating point conditional branches and
640 /// conditional moves which use condition code CC should be inverted.
invertFPCondCodeUser(Mips::CondCode CC)641 static bool invertFPCondCodeUser(Mips::CondCode CC) {
642   if (CC >= Mips::FCOND_F && CC <= Mips::FCOND_NGT)
643     return false;
644 
645   assert((CC >= Mips::FCOND_T && CC <= Mips::FCOND_GT) &&
646          "Illegal Condition Code");
647 
648   return true;
649 }
650 
651 // Creates and returns an FPCmp node from a setcc node.
652 // Returns Op if setcc is not a floating point comparison.
createFPCmp(SelectionDAG & DAG,const SDValue & Op)653 static SDValue createFPCmp(SelectionDAG &DAG, const SDValue &Op) {
654   // must be a SETCC node
655   if (Op.getOpcode() != ISD::SETCC)
656     return Op;
657 
658   SDValue LHS = Op.getOperand(0);
659 
660   if (!LHS.getValueType().isFloatingPoint())
661     return Op;
662 
663   SDValue RHS = Op.getOperand(1);
664   SDLoc DL(Op);
665 
666   // Assume the 3rd operand is a CondCodeSDNode. Add code to check the type of
667   // node if necessary.
668   ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(2))->get();
669 
670   return DAG.getNode(MipsISD::FPCmp, DL, MVT::Glue, LHS, RHS,
671                      DAG.getConstant(condCodeToFCC(CC), DL, MVT::i32));
672 }
673 
674 // Creates and returns a CMovFPT/F node.
createCMovFP(SelectionDAG & DAG,SDValue Cond,SDValue True,SDValue False,const SDLoc & DL)675 static SDValue createCMovFP(SelectionDAG &DAG, SDValue Cond, SDValue True,
676                             SDValue False, const SDLoc &DL) {
677   ConstantSDNode *CC = cast<ConstantSDNode>(Cond.getOperand(2));
678   bool invert = invertFPCondCodeUser((Mips::CondCode)CC->getSExtValue());
679   SDValue FCC0 = DAG.getRegister(Mips::FCC0, MVT::i32);
680 
681   return DAG.getNode((invert ? MipsISD::CMovFP_F : MipsISD::CMovFP_T), DL,
682                      True.getValueType(), True, FCC0, False, Cond);
683 }
684 
performSELECTCombine(SDNode * N,SelectionDAG & DAG,TargetLowering::DAGCombinerInfo & DCI,const MipsSubtarget & Subtarget)685 static SDValue performSELECTCombine(SDNode *N, SelectionDAG &DAG,
686                                     TargetLowering::DAGCombinerInfo &DCI,
687                                     const MipsSubtarget &Subtarget) {
688   if (DCI.isBeforeLegalizeOps())
689     return SDValue();
690 
691   SDValue SetCC = N->getOperand(0);
692 
693   if ((SetCC.getOpcode() != ISD::SETCC) ||
694       !SetCC.getOperand(0).getValueType().isInteger())
695     return SDValue();
696 
697   SDValue False = N->getOperand(2);
698   EVT FalseTy = False.getValueType();
699 
700   if (!FalseTy.isInteger())
701     return SDValue();
702 
703   ConstantSDNode *FalseC = dyn_cast<ConstantSDNode>(False);
704 
705   // If the RHS (False) is 0, we swap the order of the operands
706   // of ISD::SELECT (obviously also inverting the condition) so that we can
707   // take advantage of conditional moves using the $0 register.
708   // Example:
709   //   return (a != 0) ? x : 0;
710   //     load $reg, x
711   //     movz $reg, $0, a
712   if (!FalseC)
713     return SDValue();
714 
715   const SDLoc DL(N);
716 
717   if (!FalseC->getZExtValue()) {
718     ISD::CondCode CC = cast<CondCodeSDNode>(SetCC.getOperand(2))->get();
719     SDValue True = N->getOperand(1);
720 
721     SetCC = DAG.getSetCC(DL, SetCC.getValueType(), SetCC.getOperand(0),
722                          SetCC.getOperand(1),
723                          ISD::getSetCCInverse(CC, SetCC.getValueType()));
724 
725     return DAG.getNode(ISD::SELECT, DL, FalseTy, SetCC, False, True);
726   }
727 
728   // If both operands are integer constants there's a possibility that we
729   // can do some interesting optimizations.
730   SDValue True = N->getOperand(1);
731   ConstantSDNode *TrueC = dyn_cast<ConstantSDNode>(True);
732 
733   if (!TrueC || !True.getValueType().isInteger())
734     return SDValue();
735 
736   // We'll also ignore MVT::i64 operands as this optimizations proves
737   // to be ineffective because of the required sign extensions as the result
738   // of a SETCC operator is always MVT::i32 for non-vector types.
739   if (True.getValueType() == MVT::i64)
740     return SDValue();
741 
742   int64_t Diff = TrueC->getSExtValue() - FalseC->getSExtValue();
743 
744   // 1)  (a < x) ? y : y-1
745   //  slti $reg1, a, x
746   //  addiu $reg2, $reg1, y-1
747   if (Diff == 1)
748     return DAG.getNode(ISD::ADD, DL, SetCC.getValueType(), SetCC, False);
749 
750   // 2)  (a < x) ? y-1 : y
751   //  slti $reg1, a, x
752   //  xor $reg1, $reg1, 1
753   //  addiu $reg2, $reg1, y-1
754   if (Diff == -1) {
755     ISD::CondCode CC = cast<CondCodeSDNode>(SetCC.getOperand(2))->get();
756     SetCC = DAG.getSetCC(DL, SetCC.getValueType(), SetCC.getOperand(0),
757                          SetCC.getOperand(1),
758                          ISD::getSetCCInverse(CC, SetCC.getValueType()));
759     return DAG.getNode(ISD::ADD, DL, SetCC.getValueType(), SetCC, True);
760   }
761 
762   // Could not optimize.
763   return SDValue();
764 }
765 
performCMovFPCombine(SDNode * N,SelectionDAG & DAG,TargetLowering::DAGCombinerInfo & DCI,const MipsSubtarget & Subtarget)766 static SDValue performCMovFPCombine(SDNode *N, SelectionDAG &DAG,
767                                     TargetLowering::DAGCombinerInfo &DCI,
768                                     const MipsSubtarget &Subtarget) {
769   if (DCI.isBeforeLegalizeOps())
770     return SDValue();
771 
772   SDValue ValueIfTrue = N->getOperand(0), ValueIfFalse = N->getOperand(2);
773 
774   ConstantSDNode *FalseC = dyn_cast<ConstantSDNode>(ValueIfFalse);
775   if (!FalseC || FalseC->getZExtValue())
776     return SDValue();
777 
778   // Since RHS (False) is 0, we swap the order of the True/False operands
779   // (obviously also inverting the condition) so that we can
780   // take advantage of conditional moves using the $0 register.
781   // Example:
782   //   return (a != 0) ? x : 0;
783   //     load $reg, x
784   //     movz $reg, $0, a
785   unsigned Opc = (N->getOpcode() == MipsISD::CMovFP_T) ? MipsISD::CMovFP_F :
786                                                          MipsISD::CMovFP_T;
787 
788   SDValue FCC = N->getOperand(1), Glue = N->getOperand(3);
789   return DAG.getNode(Opc, SDLoc(N), ValueIfFalse.getValueType(),
790                      ValueIfFalse, FCC, ValueIfTrue, Glue);
791 }
792 
performANDCombine(SDNode * N,SelectionDAG & DAG,TargetLowering::DAGCombinerInfo & DCI,const MipsSubtarget & Subtarget)793 static SDValue performANDCombine(SDNode *N, SelectionDAG &DAG,
794                                  TargetLowering::DAGCombinerInfo &DCI,
795                                  const MipsSubtarget &Subtarget) {
796   if (DCI.isBeforeLegalizeOps() || !Subtarget.hasExtractInsert())
797     return SDValue();
798 
799   SDValue FirstOperand = N->getOperand(0);
800   unsigned FirstOperandOpc = FirstOperand.getOpcode();
801   SDValue Mask = N->getOperand(1);
802   EVT ValTy = N->getValueType(0);
803   SDLoc DL(N);
804 
805   uint64_t Pos = 0;
806   unsigned SMPos, SMSize;
807   ConstantSDNode *CN;
808   SDValue NewOperand;
809   unsigned Opc;
810 
811   // Op's second operand must be a shifted mask.
812   if (!(CN = dyn_cast<ConstantSDNode>(Mask)) ||
813       !isShiftedMask_64(CN->getZExtValue(), SMPos, SMSize))
814     return SDValue();
815 
816   if (FirstOperandOpc == ISD::SRA || FirstOperandOpc == ISD::SRL) {
817     // Pattern match EXT.
818     //  $dst = and ((sra or srl) $src , pos), (2**size - 1)
819     //  => ext $dst, $src, pos, size
820 
821     // The second operand of the shift must be an immediate.
822     if (!(CN = dyn_cast<ConstantSDNode>(FirstOperand.getOperand(1))))
823       return SDValue();
824 
825     Pos = CN->getZExtValue();
826 
827     // Return if the shifted mask does not start at bit 0 or the sum of its size
828     // and Pos exceeds the word's size.
829     if (SMPos != 0 || Pos + SMSize > ValTy.getSizeInBits())
830       return SDValue();
831 
832     Opc = MipsISD::Ext;
833     NewOperand = FirstOperand.getOperand(0);
834   } else if (FirstOperandOpc == ISD::SHL && Subtarget.hasCnMips()) {
835     // Pattern match CINS.
836     //  $dst = and (shl $src , pos), mask
837     //  => cins $dst, $src, pos, size
838     // mask is a shifted mask with consecutive 1's, pos = shift amount,
839     // size = population count.
840 
841     // The second operand of the shift must be an immediate.
842     if (!(CN = dyn_cast<ConstantSDNode>(FirstOperand.getOperand(1))))
843       return SDValue();
844 
845     Pos = CN->getZExtValue();
846 
847     if (SMPos != Pos || Pos >= ValTy.getSizeInBits() || SMSize >= 32 ||
848         Pos + SMSize > ValTy.getSizeInBits())
849       return SDValue();
850 
851     NewOperand = FirstOperand.getOperand(0);
852     // SMSize is 'location' (position) in this case, not size.
853     SMSize--;
854     Opc = MipsISD::CIns;
855   } else {
856     // Pattern match EXT.
857     //  $dst = and $src, (2**size - 1) , if size > 16
858     //  => ext $dst, $src, pos, size , pos = 0
859 
860     // If the mask is <= 0xffff, andi can be used instead.
861     if (CN->getZExtValue() <= 0xffff)
862       return SDValue();
863 
864     // Return if the mask doesn't start at position 0.
865     if (SMPos)
866       return SDValue();
867 
868     Opc = MipsISD::Ext;
869     NewOperand = FirstOperand;
870   }
871   return DAG.getNode(Opc, DL, ValTy, NewOperand,
872                      DAG.getConstant(Pos, DL, MVT::i32),
873                      DAG.getConstant(SMSize, DL, MVT::i32));
874 }
875 
performORCombine(SDNode * N,SelectionDAG & DAG,TargetLowering::DAGCombinerInfo & DCI,const MipsSubtarget & Subtarget)876 static SDValue performORCombine(SDNode *N, SelectionDAG &DAG,
877                                 TargetLowering::DAGCombinerInfo &DCI,
878                                 const MipsSubtarget &Subtarget) {
879   // Pattern match INS.
880   //  $dst = or (and $src1 , mask0), (and (shl $src, pos), mask1),
881   //  where mask1 = (2**size - 1) << pos, mask0 = ~mask1
882   //  => ins $dst, $src, size, pos, $src1
883   if (DCI.isBeforeLegalizeOps() || !Subtarget.hasExtractInsert())
884     return SDValue();
885 
886   SDValue And0 = N->getOperand(0), And1 = N->getOperand(1);
887   unsigned SMPos0, SMSize0, SMPos1, SMSize1;
888   ConstantSDNode *CN, *CN1;
889 
890   // See if Op's first operand matches (and $src1 , mask0).
891   if (And0.getOpcode() != ISD::AND)
892     return SDValue();
893 
894   if (!(CN = dyn_cast<ConstantSDNode>(And0.getOperand(1))) ||
895       !isShiftedMask_64(~CN->getSExtValue(), SMPos0, SMSize0))
896     return SDValue();
897 
898   // See if Op's second operand matches (and (shl $src, pos), mask1).
899   if (And1.getOpcode() == ISD::AND &&
900       And1.getOperand(0).getOpcode() == ISD::SHL) {
901 
902     if (!(CN = dyn_cast<ConstantSDNode>(And1.getOperand(1))) ||
903         !isShiftedMask_64(CN->getZExtValue(), SMPos1, SMSize1))
904       return SDValue();
905 
906     // The shift masks must have the same position and size.
907     if (SMPos0 != SMPos1 || SMSize0 != SMSize1)
908       return SDValue();
909 
910     SDValue Shl = And1.getOperand(0);
911 
912     if (!(CN = dyn_cast<ConstantSDNode>(Shl.getOperand(1))))
913       return SDValue();
914 
915     unsigned Shamt = CN->getZExtValue();
916 
917     // Return if the shift amount and the first bit position of mask are not the
918     // same.
919     EVT ValTy = N->getValueType(0);
920     if ((Shamt != SMPos0) || (SMPos0 + SMSize0 > ValTy.getSizeInBits()))
921       return SDValue();
922 
923     SDLoc DL(N);
924     return DAG.getNode(MipsISD::Ins, DL, ValTy, Shl.getOperand(0),
925                        DAG.getConstant(SMPos0, DL, MVT::i32),
926                        DAG.getConstant(SMSize0, DL, MVT::i32),
927                        And0.getOperand(0));
928   } else {
929     // Pattern match DINS.
930     //  $dst = or (and $src, mask0), mask1
931     //  where mask0 = ((1 << SMSize0) -1) << SMPos0
932     //  => dins $dst, $src, pos, size
933     if (~CN->getSExtValue() == ((((int64_t)1 << SMSize0) - 1) << SMPos0) &&
934         ((SMSize0 + SMPos0 <= 64 && Subtarget.hasMips64r2()) ||
935          (SMSize0 + SMPos0 <= 32))) {
936       // Check if AND instruction has constant as argument
937       bool isConstCase = And1.getOpcode() != ISD::AND;
938       if (And1.getOpcode() == ISD::AND) {
939         if (!(CN1 = dyn_cast<ConstantSDNode>(And1->getOperand(1))))
940           return SDValue();
941       } else {
942         if (!(CN1 = dyn_cast<ConstantSDNode>(N->getOperand(1))))
943           return SDValue();
944       }
945       // Don't generate INS if constant OR operand doesn't fit into bits
946       // cleared by constant AND operand.
947       if (CN->getSExtValue() & CN1->getSExtValue())
948         return SDValue();
949 
950       SDLoc DL(N);
951       EVT ValTy = N->getOperand(0)->getValueType(0);
952       SDValue Const1;
953       SDValue SrlX;
954       if (!isConstCase) {
955         Const1 = DAG.getConstant(SMPos0, DL, MVT::i32);
956         SrlX = DAG.getNode(ISD::SRL, DL, And1->getValueType(0), And1, Const1);
957       }
958       return DAG.getNode(
959           MipsISD::Ins, DL, N->getValueType(0),
960           isConstCase
961               ? DAG.getConstant(CN1->getSExtValue() >> SMPos0, DL, ValTy)
962               : SrlX,
963           DAG.getConstant(SMPos0, DL, MVT::i32),
964           DAG.getConstant(ValTy.getSizeInBits() / 8 < 8 ? SMSize0 & 31
965                                                         : SMSize0,
966                           DL, MVT::i32),
967           And0->getOperand(0));
968 
969     }
970     return SDValue();
971   }
972 }
973 
performMADD_MSUBCombine(SDNode * ROOTNode,SelectionDAG & CurDAG,const MipsSubtarget & Subtarget)974 static SDValue performMADD_MSUBCombine(SDNode *ROOTNode, SelectionDAG &CurDAG,
975                                        const MipsSubtarget &Subtarget) {
976   // ROOTNode must have a multiplication as an operand for the match to be
977   // successful.
978   if (ROOTNode->getOperand(0).getOpcode() != ISD::MUL &&
979       ROOTNode->getOperand(1).getOpcode() != ISD::MUL)
980     return SDValue();
981 
982   // In the case where we have a multiplication as the left operand of
983   // of a subtraction, we can't combine into a MipsISD::MSub node as the
984   // the instruction definition of msub(u) places the multiplication on
985   // on the right.
986   if (ROOTNode->getOpcode() == ISD::SUB &&
987       ROOTNode->getOperand(0).getOpcode() == ISD::MUL)
988     return SDValue();
989 
990   // We don't handle vector types here.
991   if (ROOTNode->getValueType(0).isVector())
992     return SDValue();
993 
994   // For MIPS64, madd / msub instructions are inefficent to use with 64 bit
995   // arithmetic. E.g.
996   // (add (mul a b) c) =>
997   //   let res = (madd (mthi (drotr c 32))x(mtlo c) a b) in
998   //   MIPS64:   (or (dsll (mfhi res) 32) (dsrl (dsll (mflo res) 32) 32)
999   //   or
1000   //   MIPS64R2: (dins (mflo res) (mfhi res) 32 32)
1001   //
1002   // The overhead of setting up the Hi/Lo registers and reassembling the
1003   // result makes this a dubious optimzation for MIPS64. The core of the
1004   // problem is that Hi/Lo contain the upper and lower 32 bits of the
1005   // operand and result.
1006   //
1007   // It requires a chain of 4 add/mul for MIPS64R2 to get better code
1008   // density than doing it naively, 5 for MIPS64. Additionally, using
1009   // madd/msub on MIPS64 requires the operands actually be 32 bit sign
1010   // extended operands, not true 64 bit values.
1011   //
1012   // FIXME: For the moment, disable this completely for MIPS64.
1013   if (Subtarget.hasMips64())
1014     return SDValue();
1015 
1016   SDValue Mult = ROOTNode->getOperand(0).getOpcode() == ISD::MUL
1017                      ? ROOTNode->getOperand(0)
1018                      : ROOTNode->getOperand(1);
1019 
1020   SDValue AddOperand = ROOTNode->getOperand(0).getOpcode() == ISD::MUL
1021                      ? ROOTNode->getOperand(1)
1022                      : ROOTNode->getOperand(0);
1023 
1024   // Transform this to a MADD only if the user of this node is the add.
1025   // If there are other users of the mul, this function returns here.
1026   if (!Mult.hasOneUse())
1027     return SDValue();
1028 
1029   // maddu and madd are unusual instructions in that on MIPS64 bits 63..31
1030   // must be in canonical form, i.e. sign extended. For MIPS32, the operands
1031   // of the multiply must have 32 or more sign bits, otherwise we cannot
1032   // perform this optimization. We have to check this here as we're performing
1033   // this optimization pre-legalization.
1034   SDValue MultLHS = Mult->getOperand(0);
1035   SDValue MultRHS = Mult->getOperand(1);
1036 
1037   bool IsSigned = MultLHS->getOpcode() == ISD::SIGN_EXTEND &&
1038                   MultRHS->getOpcode() == ISD::SIGN_EXTEND;
1039   bool IsUnsigned = MultLHS->getOpcode() == ISD::ZERO_EXTEND &&
1040                     MultRHS->getOpcode() == ISD::ZERO_EXTEND;
1041 
1042   if (!IsSigned && !IsUnsigned)
1043     return SDValue();
1044 
1045   // Initialize accumulator.
1046   SDLoc DL(ROOTNode);
1047   SDValue BottomHalf, TopHalf;
1048   std::tie(BottomHalf, TopHalf) =
1049       CurDAG.SplitScalar(AddOperand, DL, MVT::i32, MVT::i32);
1050   SDValue ACCIn =
1051       CurDAG.getNode(MipsISD::MTLOHI, DL, MVT::Untyped, BottomHalf, TopHalf);
1052 
1053   // Create MipsMAdd(u) / MipsMSub(u) node.
1054   bool IsAdd = ROOTNode->getOpcode() == ISD::ADD;
1055   unsigned Opcode = IsAdd ? (IsUnsigned ? MipsISD::MAddu : MipsISD::MAdd)
1056                           : (IsUnsigned ? MipsISD::MSubu : MipsISD::MSub);
1057   SDValue MAddOps[3] = {
1058       CurDAG.getNode(ISD::TRUNCATE, DL, MVT::i32, Mult->getOperand(0)),
1059       CurDAG.getNode(ISD::TRUNCATE, DL, MVT::i32, Mult->getOperand(1)), ACCIn};
1060   EVT VTs[2] = {MVT::i32, MVT::i32};
1061   SDValue MAdd = CurDAG.getNode(Opcode, DL, VTs, MAddOps);
1062 
1063   SDValue ResLo = CurDAG.getNode(MipsISD::MFLO, DL, MVT::i32, MAdd);
1064   SDValue ResHi = CurDAG.getNode(MipsISD::MFHI, DL, MVT::i32, MAdd);
1065   SDValue Combined =
1066       CurDAG.getNode(ISD::BUILD_PAIR, DL, MVT::i64, ResLo, ResHi);
1067   return Combined;
1068 }
1069 
performSUBCombine(SDNode * N,SelectionDAG & DAG,TargetLowering::DAGCombinerInfo & DCI,const MipsSubtarget & Subtarget)1070 static SDValue performSUBCombine(SDNode *N, SelectionDAG &DAG,
1071                                  TargetLowering::DAGCombinerInfo &DCI,
1072                                  const MipsSubtarget &Subtarget) {
1073   // (sub v0 (mul v1, v2)) => (msub v1, v2, v0)
1074   if (DCI.isBeforeLegalizeOps()) {
1075     if (Subtarget.hasMips32() && !Subtarget.hasMips32r6() &&
1076         !Subtarget.inMips16Mode() && N->getValueType(0) == MVT::i64)
1077       return performMADD_MSUBCombine(N, DAG, Subtarget);
1078 
1079     return SDValue();
1080   }
1081 
1082   return SDValue();
1083 }
1084 
performADDCombine(SDNode * N,SelectionDAG & DAG,TargetLowering::DAGCombinerInfo & DCI,const MipsSubtarget & Subtarget)1085 static SDValue performADDCombine(SDNode *N, SelectionDAG &DAG,
1086                                  TargetLowering::DAGCombinerInfo &DCI,
1087                                  const MipsSubtarget &Subtarget) {
1088   // (add v0 (mul v1, v2)) => (madd v1, v2, v0)
1089   if (DCI.isBeforeLegalizeOps()) {
1090     if (Subtarget.hasMips32() && !Subtarget.hasMips32r6() &&
1091         !Subtarget.inMips16Mode() && N->getValueType(0) == MVT::i64)
1092       return performMADD_MSUBCombine(N, DAG, Subtarget);
1093 
1094     return SDValue();
1095   }
1096 
1097   // (add v0, (add v1, abs_lo(tjt))) => (add (add v0, v1), abs_lo(tjt))
1098   SDValue Add = N->getOperand(1);
1099 
1100   if (Add.getOpcode() != ISD::ADD)
1101     return SDValue();
1102 
1103   SDValue Lo = Add.getOperand(1);
1104 
1105   if ((Lo.getOpcode() != MipsISD::Lo) ||
1106       (Lo.getOperand(0).getOpcode() != ISD::TargetJumpTable))
1107     return SDValue();
1108 
1109   EVT ValTy = N->getValueType(0);
1110   SDLoc DL(N);
1111 
1112   SDValue Add1 = DAG.getNode(ISD::ADD, DL, ValTy, N->getOperand(0),
1113                              Add.getOperand(0));
1114   return DAG.getNode(ISD::ADD, DL, ValTy, Add1, Lo);
1115 }
1116 
performSHLCombine(SDNode * N,SelectionDAG & DAG,TargetLowering::DAGCombinerInfo & DCI,const MipsSubtarget & Subtarget)1117 static SDValue performSHLCombine(SDNode *N, SelectionDAG &DAG,
1118                                  TargetLowering::DAGCombinerInfo &DCI,
1119                                  const MipsSubtarget &Subtarget) {
1120   // Pattern match CINS.
1121   //  $dst = shl (and $src , imm), pos
1122   //  => cins $dst, $src, pos, size
1123 
1124   if (DCI.isBeforeLegalizeOps() || !Subtarget.hasCnMips())
1125     return SDValue();
1126 
1127   SDValue FirstOperand = N->getOperand(0);
1128   unsigned FirstOperandOpc = FirstOperand.getOpcode();
1129   SDValue SecondOperand = N->getOperand(1);
1130   EVT ValTy = N->getValueType(0);
1131   SDLoc DL(N);
1132 
1133   uint64_t Pos = 0;
1134   unsigned SMPos, SMSize;
1135   ConstantSDNode *CN;
1136   SDValue NewOperand;
1137 
1138   // The second operand of the shift must be an immediate.
1139   if (!(CN = dyn_cast<ConstantSDNode>(SecondOperand)))
1140     return SDValue();
1141 
1142   Pos = CN->getZExtValue();
1143 
1144   if (Pos >= ValTy.getSizeInBits())
1145     return SDValue();
1146 
1147   if (FirstOperandOpc != ISD::AND)
1148     return SDValue();
1149 
1150   // AND's second operand must be a shifted mask.
1151   if (!(CN = dyn_cast<ConstantSDNode>(FirstOperand.getOperand(1))) ||
1152       !isShiftedMask_64(CN->getZExtValue(), SMPos, SMSize))
1153     return SDValue();
1154 
1155   // Return if the shifted mask does not start at bit 0 or the sum of its size
1156   // and Pos exceeds the word's size.
1157   if (SMPos != 0 || SMSize > 32 || Pos + SMSize > ValTy.getSizeInBits())
1158     return SDValue();
1159 
1160   NewOperand = FirstOperand.getOperand(0);
1161   // SMSize is 'location' (position) in this case, not size.
1162   SMSize--;
1163 
1164   return DAG.getNode(MipsISD::CIns, DL, ValTy, NewOperand,
1165                      DAG.getConstant(Pos, DL, MVT::i32),
1166                      DAG.getConstant(SMSize, DL, MVT::i32));
1167 }
1168 
PerformDAGCombine(SDNode * N,DAGCombinerInfo & DCI) const1169 SDValue  MipsTargetLowering::PerformDAGCombine(SDNode *N, DAGCombinerInfo &DCI)
1170   const {
1171   SelectionDAG &DAG = DCI.DAG;
1172   unsigned Opc = N->getOpcode();
1173 
1174   switch (Opc) {
1175   default: break;
1176   case ISD::SDIVREM:
1177   case ISD::UDIVREM:
1178     return performDivRemCombine(N, DAG, DCI, Subtarget);
1179   case ISD::SELECT:
1180     return performSELECTCombine(N, DAG, DCI, Subtarget);
1181   case MipsISD::CMovFP_F:
1182   case MipsISD::CMovFP_T:
1183     return performCMovFPCombine(N, DAG, DCI, Subtarget);
1184   case ISD::AND:
1185     return performANDCombine(N, DAG, DCI, Subtarget);
1186   case ISD::OR:
1187     return performORCombine(N, DAG, DCI, Subtarget);
1188   case ISD::ADD:
1189     return performADDCombine(N, DAG, DCI, Subtarget);
1190   case ISD::SHL:
1191     return performSHLCombine(N, DAG, DCI, Subtarget);
1192   case ISD::SUB:
1193     return performSUBCombine(N, DAG, DCI, Subtarget);
1194   }
1195 
1196   return SDValue();
1197 }
1198 
isCheapToSpeculateCttz(Type * Ty) const1199 bool MipsTargetLowering::isCheapToSpeculateCttz(Type *Ty) const {
1200   return Subtarget.hasMips32();
1201 }
1202 
isCheapToSpeculateCtlz(Type * Ty) const1203 bool MipsTargetLowering::isCheapToSpeculateCtlz(Type *Ty) const {
1204   return Subtarget.hasMips32();
1205 }
1206 
hasBitTest(SDValue X,SDValue Y) const1207 bool MipsTargetLowering::hasBitTest(SDValue X, SDValue Y) const {
1208   // We can use ANDI+SLTIU as a bit test. Y contains the bit position.
1209   // For MIPSR2 or later, we may be able to use the `ext` instruction or its'
1210   // double-word variants.
1211   if (auto *C = dyn_cast<ConstantSDNode>(Y))
1212     return C->getAPIntValue().ule(15);
1213 
1214   return false;
1215 }
1216 
shouldFoldConstantShiftPairToMask(const SDNode * N,CombineLevel Level) const1217 bool MipsTargetLowering::shouldFoldConstantShiftPairToMask(
1218     const SDNode *N, CombineLevel Level) const {
1219   assert(((N->getOpcode() == ISD::SHL &&
1220            N->getOperand(0).getOpcode() == ISD::SRL) ||
1221           (N->getOpcode() == ISD::SRL &&
1222            N->getOperand(0).getOpcode() == ISD::SHL)) &&
1223          "Expected shift-shift mask");
1224 
1225   if (N->getOperand(0).getValueType().isVector())
1226     return false;
1227   return true;
1228 }
1229 
1230 void
ReplaceNodeResults(SDNode * N,SmallVectorImpl<SDValue> & Results,SelectionDAG & DAG) const1231 MipsTargetLowering::ReplaceNodeResults(SDNode *N,
1232                                        SmallVectorImpl<SDValue> &Results,
1233                                        SelectionDAG &DAG) const {
1234   return LowerOperationWrapper(N, Results, DAG);
1235 }
1236 
1237 SDValue MipsTargetLowering::
LowerOperation(SDValue Op,SelectionDAG & DAG) const1238 LowerOperation(SDValue Op, SelectionDAG &DAG) const
1239 {
1240   switch (Op.getOpcode())
1241   {
1242   case ISD::BRCOND:             return lowerBRCOND(Op, DAG);
1243   case ISD::ConstantPool:       return lowerConstantPool(Op, DAG);
1244   case ISD::GlobalAddress:      return lowerGlobalAddress(Op, DAG);
1245   case ISD::BlockAddress:       return lowerBlockAddress(Op, DAG);
1246   case ISD::GlobalTLSAddress:   return lowerGlobalTLSAddress(Op, DAG);
1247   case ISD::JumpTable:          return lowerJumpTable(Op, DAG);
1248   case ISD::SELECT:             return lowerSELECT(Op, DAG);
1249   case ISD::SETCC:              return lowerSETCC(Op, DAG);
1250   case ISD::VASTART:            return lowerVASTART(Op, DAG);
1251   case ISD::VAARG:              return lowerVAARG(Op, DAG);
1252   case ISD::FCOPYSIGN:          return lowerFCOPYSIGN(Op, DAG);
1253   case ISD::FABS:               return lowerFABS(Op, DAG);
1254   case ISD::FRAMEADDR:          return lowerFRAMEADDR(Op, DAG);
1255   case ISD::RETURNADDR:         return lowerRETURNADDR(Op, DAG);
1256   case ISD::EH_RETURN:          return lowerEH_RETURN(Op, DAG);
1257   case ISD::ATOMIC_FENCE:       return lowerATOMIC_FENCE(Op, DAG);
1258   case ISD::SHL_PARTS:          return lowerShiftLeftParts(Op, DAG);
1259   case ISD::SRA_PARTS:          return lowerShiftRightParts(Op, DAG, true);
1260   case ISD::SRL_PARTS:          return lowerShiftRightParts(Op, DAG, false);
1261   case ISD::LOAD:               return lowerLOAD(Op, DAG);
1262   case ISD::STORE:              return lowerSTORE(Op, DAG);
1263   case ISD::EH_DWARF_CFA:       return lowerEH_DWARF_CFA(Op, DAG);
1264   case ISD::FP_TO_SINT:         return lowerFP_TO_SINT(Op, DAG);
1265   }
1266   return SDValue();
1267 }
1268 
1269 //===----------------------------------------------------------------------===//
1270 //  Lower helper functions
1271 //===----------------------------------------------------------------------===//
1272 
1273 // addLiveIn - This helper function adds the specified physical register to the
1274 // MachineFunction as a live in value.  It also creates a corresponding
1275 // virtual register for it.
1276 static unsigned
addLiveIn(MachineFunction & MF,unsigned PReg,const TargetRegisterClass * RC)1277 addLiveIn(MachineFunction &MF, unsigned PReg, const TargetRegisterClass *RC)
1278 {
1279   Register VReg = MF.getRegInfo().createVirtualRegister(RC);
1280   MF.getRegInfo().addLiveIn(PReg, VReg);
1281   return VReg;
1282 }
1283 
insertDivByZeroTrap(MachineInstr & MI,MachineBasicBlock & MBB,const TargetInstrInfo & TII,bool Is64Bit,bool IsMicroMips)1284 static MachineBasicBlock *insertDivByZeroTrap(MachineInstr &MI,
1285                                               MachineBasicBlock &MBB,
1286                                               const TargetInstrInfo &TII,
1287                                               bool Is64Bit, bool IsMicroMips) {
1288   if (NoZeroDivCheck)
1289     return &MBB;
1290 
1291   // Insert instruction "teq $divisor_reg, $zero, 7".
1292   MachineBasicBlock::iterator I(MI);
1293   MachineInstrBuilder MIB;
1294   MachineOperand &Divisor = MI.getOperand(2);
1295   MIB = BuildMI(MBB, std::next(I), MI.getDebugLoc(),
1296                 TII.get(IsMicroMips ? Mips::TEQ_MM : Mips::TEQ))
1297             .addReg(Divisor.getReg(), getKillRegState(Divisor.isKill()))
1298             .addReg(Mips::ZERO)
1299             .addImm(7);
1300 
1301   // Use the 32-bit sub-register if this is a 64-bit division.
1302   if (Is64Bit)
1303     MIB->getOperand(0).setSubReg(Mips::sub_32);
1304 
1305   // Clear Divisor's kill flag.
1306   Divisor.setIsKill(false);
1307 
1308   // We would normally delete the original instruction here but in this case
1309   // we only needed to inject an additional instruction rather than replace it.
1310 
1311   return &MBB;
1312 }
1313 
1314 MachineBasicBlock *
EmitInstrWithCustomInserter(MachineInstr & MI,MachineBasicBlock * BB) const1315 MipsTargetLowering::EmitInstrWithCustomInserter(MachineInstr &MI,
1316                                                 MachineBasicBlock *BB) const {
1317   switch (MI.getOpcode()) {
1318   default:
1319     llvm_unreachable("Unexpected instr type to insert");
1320   case Mips::ATOMIC_LOAD_ADD_I8:
1321     return emitAtomicBinaryPartword(MI, BB, 1);
1322   case Mips::ATOMIC_LOAD_ADD_I16:
1323     return emitAtomicBinaryPartword(MI, BB, 2);
1324   case Mips::ATOMIC_LOAD_ADD_I32:
1325     return emitAtomicBinary(MI, BB);
1326   case Mips::ATOMIC_LOAD_ADD_I64:
1327     return emitAtomicBinary(MI, BB);
1328 
1329   case Mips::ATOMIC_LOAD_AND_I8:
1330     return emitAtomicBinaryPartword(MI, BB, 1);
1331   case Mips::ATOMIC_LOAD_AND_I16:
1332     return emitAtomicBinaryPartword(MI, BB, 2);
1333   case Mips::ATOMIC_LOAD_AND_I32:
1334     return emitAtomicBinary(MI, BB);
1335   case Mips::ATOMIC_LOAD_AND_I64:
1336     return emitAtomicBinary(MI, BB);
1337 
1338   case Mips::ATOMIC_LOAD_OR_I8:
1339     return emitAtomicBinaryPartword(MI, BB, 1);
1340   case Mips::ATOMIC_LOAD_OR_I16:
1341     return emitAtomicBinaryPartword(MI, BB, 2);
1342   case Mips::ATOMIC_LOAD_OR_I32:
1343     return emitAtomicBinary(MI, BB);
1344   case Mips::ATOMIC_LOAD_OR_I64:
1345     return emitAtomicBinary(MI, BB);
1346 
1347   case Mips::ATOMIC_LOAD_XOR_I8:
1348     return emitAtomicBinaryPartword(MI, BB, 1);
1349   case Mips::ATOMIC_LOAD_XOR_I16:
1350     return emitAtomicBinaryPartword(MI, BB, 2);
1351   case Mips::ATOMIC_LOAD_XOR_I32:
1352     return emitAtomicBinary(MI, BB);
1353   case Mips::ATOMIC_LOAD_XOR_I64:
1354     return emitAtomicBinary(MI, BB);
1355 
1356   case Mips::ATOMIC_LOAD_NAND_I8:
1357     return emitAtomicBinaryPartword(MI, BB, 1);
1358   case Mips::ATOMIC_LOAD_NAND_I16:
1359     return emitAtomicBinaryPartword(MI, BB, 2);
1360   case Mips::ATOMIC_LOAD_NAND_I32:
1361     return emitAtomicBinary(MI, BB);
1362   case Mips::ATOMIC_LOAD_NAND_I64:
1363     return emitAtomicBinary(MI, BB);
1364 
1365   case Mips::ATOMIC_LOAD_SUB_I8:
1366     return emitAtomicBinaryPartword(MI, BB, 1);
1367   case Mips::ATOMIC_LOAD_SUB_I16:
1368     return emitAtomicBinaryPartword(MI, BB, 2);
1369   case Mips::ATOMIC_LOAD_SUB_I32:
1370     return emitAtomicBinary(MI, BB);
1371   case Mips::ATOMIC_LOAD_SUB_I64:
1372     return emitAtomicBinary(MI, BB);
1373 
1374   case Mips::ATOMIC_SWAP_I8:
1375     return emitAtomicBinaryPartword(MI, BB, 1);
1376   case Mips::ATOMIC_SWAP_I16:
1377     return emitAtomicBinaryPartword(MI, BB, 2);
1378   case Mips::ATOMIC_SWAP_I32:
1379     return emitAtomicBinary(MI, BB);
1380   case Mips::ATOMIC_SWAP_I64:
1381     return emitAtomicBinary(MI, BB);
1382 
1383   case Mips::ATOMIC_CMP_SWAP_I8:
1384     return emitAtomicCmpSwapPartword(MI, BB, 1);
1385   case Mips::ATOMIC_CMP_SWAP_I16:
1386     return emitAtomicCmpSwapPartword(MI, BB, 2);
1387   case Mips::ATOMIC_CMP_SWAP_I32:
1388     return emitAtomicCmpSwap(MI, BB);
1389   case Mips::ATOMIC_CMP_SWAP_I64:
1390     return emitAtomicCmpSwap(MI, BB);
1391 
1392   case Mips::ATOMIC_LOAD_MIN_I8:
1393     return emitAtomicBinaryPartword(MI, BB, 1);
1394   case Mips::ATOMIC_LOAD_MIN_I16:
1395     return emitAtomicBinaryPartword(MI, BB, 2);
1396   case Mips::ATOMIC_LOAD_MIN_I32:
1397     return emitAtomicBinary(MI, BB);
1398   case Mips::ATOMIC_LOAD_MIN_I64:
1399     return emitAtomicBinary(MI, BB);
1400 
1401   case Mips::ATOMIC_LOAD_MAX_I8:
1402     return emitAtomicBinaryPartword(MI, BB, 1);
1403   case Mips::ATOMIC_LOAD_MAX_I16:
1404     return emitAtomicBinaryPartword(MI, BB, 2);
1405   case Mips::ATOMIC_LOAD_MAX_I32:
1406     return emitAtomicBinary(MI, BB);
1407   case Mips::ATOMIC_LOAD_MAX_I64:
1408     return emitAtomicBinary(MI, BB);
1409 
1410   case Mips::ATOMIC_LOAD_UMIN_I8:
1411     return emitAtomicBinaryPartword(MI, BB, 1);
1412   case Mips::ATOMIC_LOAD_UMIN_I16:
1413     return emitAtomicBinaryPartword(MI, BB, 2);
1414   case Mips::ATOMIC_LOAD_UMIN_I32:
1415     return emitAtomicBinary(MI, BB);
1416   case Mips::ATOMIC_LOAD_UMIN_I64:
1417     return emitAtomicBinary(MI, BB);
1418 
1419   case Mips::ATOMIC_LOAD_UMAX_I8:
1420     return emitAtomicBinaryPartword(MI, BB, 1);
1421   case Mips::ATOMIC_LOAD_UMAX_I16:
1422     return emitAtomicBinaryPartword(MI, BB, 2);
1423   case Mips::ATOMIC_LOAD_UMAX_I32:
1424     return emitAtomicBinary(MI, BB);
1425   case Mips::ATOMIC_LOAD_UMAX_I64:
1426     return emitAtomicBinary(MI, BB);
1427 
1428   case Mips::PseudoSDIV:
1429   case Mips::PseudoUDIV:
1430   case Mips::DIV:
1431   case Mips::DIVU:
1432   case Mips::MOD:
1433   case Mips::MODU:
1434     return insertDivByZeroTrap(MI, *BB, *Subtarget.getInstrInfo(), false,
1435                                false);
1436   case Mips::SDIV_MM_Pseudo:
1437   case Mips::UDIV_MM_Pseudo:
1438   case Mips::SDIV_MM:
1439   case Mips::UDIV_MM:
1440   case Mips::DIV_MMR6:
1441   case Mips::DIVU_MMR6:
1442   case Mips::MOD_MMR6:
1443   case Mips::MODU_MMR6:
1444     return insertDivByZeroTrap(MI, *BB, *Subtarget.getInstrInfo(), false, true);
1445   case Mips::PseudoDSDIV:
1446   case Mips::PseudoDUDIV:
1447   case Mips::DDIV:
1448   case Mips::DDIVU:
1449   case Mips::DMOD:
1450   case Mips::DMODU:
1451     return insertDivByZeroTrap(MI, *BB, *Subtarget.getInstrInfo(), true, false);
1452 
1453   case Mips::PseudoSELECT_I:
1454   case Mips::PseudoSELECT_I64:
1455   case Mips::PseudoSELECT_S:
1456   case Mips::PseudoSELECT_D32:
1457   case Mips::PseudoSELECT_D64:
1458     return emitPseudoSELECT(MI, BB, false, Mips::BNE);
1459   case Mips::PseudoSELECTFP_F_I:
1460   case Mips::PseudoSELECTFP_F_I64:
1461   case Mips::PseudoSELECTFP_F_S:
1462   case Mips::PseudoSELECTFP_F_D32:
1463   case Mips::PseudoSELECTFP_F_D64:
1464     return emitPseudoSELECT(MI, BB, true, Mips::BC1F);
1465   case Mips::PseudoSELECTFP_T_I:
1466   case Mips::PseudoSELECTFP_T_I64:
1467   case Mips::PseudoSELECTFP_T_S:
1468   case Mips::PseudoSELECTFP_T_D32:
1469   case Mips::PseudoSELECTFP_T_D64:
1470     return emitPseudoSELECT(MI, BB, true, Mips::BC1T);
1471   case Mips::PseudoD_SELECT_I:
1472   case Mips::PseudoD_SELECT_I64:
1473     return emitPseudoD_SELECT(MI, BB);
1474   case Mips::LDR_W:
1475     return emitLDR_W(MI, BB);
1476   case Mips::LDR_D:
1477     return emitLDR_D(MI, BB);
1478   case Mips::STR_W:
1479     return emitSTR_W(MI, BB);
1480   case Mips::STR_D:
1481     return emitSTR_D(MI, BB);
1482   }
1483 }
1484 
1485 // This function also handles Mips::ATOMIC_SWAP_I32 (when BinOpcode == 0), and
1486 // Mips::ATOMIC_LOAD_NAND_I32 (when Nand == true)
1487 MachineBasicBlock *
emitAtomicBinary(MachineInstr & MI,MachineBasicBlock * BB) const1488 MipsTargetLowering::emitAtomicBinary(MachineInstr &MI,
1489                                      MachineBasicBlock *BB) const {
1490 
1491   MachineFunction *MF = BB->getParent();
1492   MachineRegisterInfo &RegInfo = MF->getRegInfo();
1493   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
1494   DebugLoc DL = MI.getDebugLoc();
1495 
1496   unsigned AtomicOp;
1497   bool NeedsAdditionalReg = false;
1498   switch (MI.getOpcode()) {
1499   case Mips::ATOMIC_LOAD_ADD_I32:
1500     AtomicOp = Mips::ATOMIC_LOAD_ADD_I32_POSTRA;
1501     break;
1502   case Mips::ATOMIC_LOAD_SUB_I32:
1503     AtomicOp = Mips::ATOMIC_LOAD_SUB_I32_POSTRA;
1504     break;
1505   case Mips::ATOMIC_LOAD_AND_I32:
1506     AtomicOp = Mips::ATOMIC_LOAD_AND_I32_POSTRA;
1507     break;
1508   case Mips::ATOMIC_LOAD_OR_I32:
1509     AtomicOp = Mips::ATOMIC_LOAD_OR_I32_POSTRA;
1510     break;
1511   case Mips::ATOMIC_LOAD_XOR_I32:
1512     AtomicOp = Mips::ATOMIC_LOAD_XOR_I32_POSTRA;
1513     break;
1514   case Mips::ATOMIC_LOAD_NAND_I32:
1515     AtomicOp = Mips::ATOMIC_LOAD_NAND_I32_POSTRA;
1516     break;
1517   case Mips::ATOMIC_SWAP_I32:
1518     AtomicOp = Mips::ATOMIC_SWAP_I32_POSTRA;
1519     break;
1520   case Mips::ATOMIC_LOAD_ADD_I64:
1521     AtomicOp = Mips::ATOMIC_LOAD_ADD_I64_POSTRA;
1522     break;
1523   case Mips::ATOMIC_LOAD_SUB_I64:
1524     AtomicOp = Mips::ATOMIC_LOAD_SUB_I64_POSTRA;
1525     break;
1526   case Mips::ATOMIC_LOAD_AND_I64:
1527     AtomicOp = Mips::ATOMIC_LOAD_AND_I64_POSTRA;
1528     break;
1529   case Mips::ATOMIC_LOAD_OR_I64:
1530     AtomicOp = Mips::ATOMIC_LOAD_OR_I64_POSTRA;
1531     break;
1532   case Mips::ATOMIC_LOAD_XOR_I64:
1533     AtomicOp = Mips::ATOMIC_LOAD_XOR_I64_POSTRA;
1534     break;
1535   case Mips::ATOMIC_LOAD_NAND_I64:
1536     AtomicOp = Mips::ATOMIC_LOAD_NAND_I64_POSTRA;
1537     break;
1538   case Mips::ATOMIC_SWAP_I64:
1539     AtomicOp = Mips::ATOMIC_SWAP_I64_POSTRA;
1540     break;
1541   case Mips::ATOMIC_LOAD_MIN_I32:
1542     AtomicOp = Mips::ATOMIC_LOAD_MIN_I32_POSTRA;
1543     NeedsAdditionalReg = true;
1544     break;
1545   case Mips::ATOMIC_LOAD_MAX_I32:
1546     AtomicOp = Mips::ATOMIC_LOAD_MAX_I32_POSTRA;
1547     NeedsAdditionalReg = true;
1548     break;
1549   case Mips::ATOMIC_LOAD_UMIN_I32:
1550     AtomicOp = Mips::ATOMIC_LOAD_UMIN_I32_POSTRA;
1551     NeedsAdditionalReg = true;
1552     break;
1553   case Mips::ATOMIC_LOAD_UMAX_I32:
1554     AtomicOp = Mips::ATOMIC_LOAD_UMAX_I32_POSTRA;
1555     NeedsAdditionalReg = true;
1556     break;
1557   case Mips::ATOMIC_LOAD_MIN_I64:
1558     AtomicOp = Mips::ATOMIC_LOAD_MIN_I64_POSTRA;
1559     NeedsAdditionalReg = true;
1560     break;
1561   case Mips::ATOMIC_LOAD_MAX_I64:
1562     AtomicOp = Mips::ATOMIC_LOAD_MAX_I64_POSTRA;
1563     NeedsAdditionalReg = true;
1564     break;
1565   case Mips::ATOMIC_LOAD_UMIN_I64:
1566     AtomicOp = Mips::ATOMIC_LOAD_UMIN_I64_POSTRA;
1567     NeedsAdditionalReg = true;
1568     break;
1569   case Mips::ATOMIC_LOAD_UMAX_I64:
1570     AtomicOp = Mips::ATOMIC_LOAD_UMAX_I64_POSTRA;
1571     NeedsAdditionalReg = true;
1572     break;
1573   default:
1574     llvm_unreachable("Unknown pseudo atomic for replacement!");
1575   }
1576 
1577   Register OldVal = MI.getOperand(0).getReg();
1578   Register Ptr = MI.getOperand(1).getReg();
1579   Register Incr = MI.getOperand(2).getReg();
1580   Register Scratch = RegInfo.createVirtualRegister(RegInfo.getRegClass(OldVal));
1581 
1582   MachineBasicBlock::iterator II(MI);
1583 
1584   // The scratch registers here with the EarlyClobber | Define | Implicit
1585   // flags is used to persuade the register allocator and the machine
1586   // verifier to accept the usage of this register. This has to be a real
1587   // register which has an UNDEF value but is dead after the instruction which
1588   // is unique among the registers chosen for the instruction.
1589 
1590   // The EarlyClobber flag has the semantic properties that the operand it is
1591   // attached to is clobbered before the rest of the inputs are read. Hence it
1592   // must be unique among the operands to the instruction.
1593   // The Define flag is needed to coerce the machine verifier that an Undef
1594   // value isn't a problem.
1595   // The Dead flag is needed as the value in scratch isn't used by any other
1596   // instruction. Kill isn't used as Dead is more precise.
1597   // The implicit flag is here due to the interaction between the other flags
1598   // and the machine verifier.
1599 
1600   // For correctness purpose, a new pseudo is introduced here. We need this
1601   // new pseudo, so that FastRegisterAllocator does not see an ll/sc sequence
1602   // that is spread over >1 basic blocks. A register allocator which
1603   // introduces (or any codegen infact) a store, can violate the expectations
1604   // of the hardware.
1605   //
1606   // An atomic read-modify-write sequence starts with a linked load
1607   // instruction and ends with a store conditional instruction. The atomic
1608   // read-modify-write sequence fails if any of the following conditions
1609   // occur between the execution of ll and sc:
1610   //   * A coherent store is completed by another process or coherent I/O
1611   //     module into the block of synchronizable physical memory containing
1612   //     the word. The size and alignment of the block is
1613   //     implementation-dependent.
1614   //   * A coherent store is executed between an LL and SC sequence on the
1615   //     same processor to the block of synchornizable physical memory
1616   //     containing the word.
1617   //
1618 
1619   Register PtrCopy = RegInfo.createVirtualRegister(RegInfo.getRegClass(Ptr));
1620   Register IncrCopy = RegInfo.createVirtualRegister(RegInfo.getRegClass(Incr));
1621 
1622   BuildMI(*BB, II, DL, TII->get(Mips::COPY), IncrCopy).addReg(Incr);
1623   BuildMI(*BB, II, DL, TII->get(Mips::COPY), PtrCopy).addReg(Ptr);
1624 
1625   MachineInstrBuilder MIB =
1626       BuildMI(*BB, II, DL, TII->get(AtomicOp))
1627           .addReg(OldVal, RegState::Define | RegState::EarlyClobber)
1628           .addReg(PtrCopy)
1629           .addReg(IncrCopy)
1630           .addReg(Scratch, RegState::Define | RegState::EarlyClobber |
1631                                RegState::Implicit | RegState::Dead);
1632   if (NeedsAdditionalReg) {
1633     Register Scratch2 =
1634         RegInfo.createVirtualRegister(RegInfo.getRegClass(OldVal));
1635     MIB.addReg(Scratch2, RegState::Define | RegState::EarlyClobber |
1636                              RegState::Implicit | RegState::Dead);
1637   }
1638 
1639   MI.eraseFromParent();
1640 
1641   return BB;
1642 }
1643 
emitSignExtendToI32InReg(MachineInstr & MI,MachineBasicBlock * BB,unsigned Size,unsigned DstReg,unsigned SrcReg) const1644 MachineBasicBlock *MipsTargetLowering::emitSignExtendToI32InReg(
1645     MachineInstr &MI, MachineBasicBlock *BB, unsigned Size, unsigned DstReg,
1646     unsigned SrcReg) const {
1647   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
1648   const DebugLoc &DL = MI.getDebugLoc();
1649 
1650   if (Subtarget.hasMips32r2() && Size == 1) {
1651     BuildMI(BB, DL, TII->get(Mips::SEB), DstReg).addReg(SrcReg);
1652     return BB;
1653   }
1654 
1655   if (Subtarget.hasMips32r2() && Size == 2) {
1656     BuildMI(BB, DL, TII->get(Mips::SEH), DstReg).addReg(SrcReg);
1657     return BB;
1658   }
1659 
1660   MachineFunction *MF = BB->getParent();
1661   MachineRegisterInfo &RegInfo = MF->getRegInfo();
1662   const TargetRegisterClass *RC = getRegClassFor(MVT::i32);
1663   Register ScrReg = RegInfo.createVirtualRegister(RC);
1664 
1665   assert(Size < 32);
1666   int64_t ShiftImm = 32 - (Size * 8);
1667 
1668   BuildMI(BB, DL, TII->get(Mips::SLL), ScrReg).addReg(SrcReg).addImm(ShiftImm);
1669   BuildMI(BB, DL, TII->get(Mips::SRA), DstReg).addReg(ScrReg).addImm(ShiftImm);
1670 
1671   return BB;
1672 }
1673 
emitAtomicBinaryPartword(MachineInstr & MI,MachineBasicBlock * BB,unsigned Size) const1674 MachineBasicBlock *MipsTargetLowering::emitAtomicBinaryPartword(
1675     MachineInstr &MI, MachineBasicBlock *BB, unsigned Size) const {
1676   assert((Size == 1 || Size == 2) &&
1677          "Unsupported size for EmitAtomicBinaryPartial.");
1678 
1679   MachineFunction *MF = BB->getParent();
1680   MachineRegisterInfo &RegInfo = MF->getRegInfo();
1681   const TargetRegisterClass *RC = getRegClassFor(MVT::i32);
1682   const bool ArePtrs64bit = ABI.ArePtrs64bit();
1683   const TargetRegisterClass *RCp =
1684     getRegClassFor(ArePtrs64bit ? MVT::i64 : MVT::i32);
1685   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
1686   DebugLoc DL = MI.getDebugLoc();
1687 
1688   Register Dest = MI.getOperand(0).getReg();
1689   Register Ptr = MI.getOperand(1).getReg();
1690   Register Incr = MI.getOperand(2).getReg();
1691 
1692   Register AlignedAddr = RegInfo.createVirtualRegister(RCp);
1693   Register ShiftAmt = RegInfo.createVirtualRegister(RC);
1694   Register Mask = RegInfo.createVirtualRegister(RC);
1695   Register Mask2 = RegInfo.createVirtualRegister(RC);
1696   Register Incr2 = RegInfo.createVirtualRegister(RC);
1697   Register MaskLSB2 = RegInfo.createVirtualRegister(RCp);
1698   Register PtrLSB2 = RegInfo.createVirtualRegister(RC);
1699   Register MaskUpper = RegInfo.createVirtualRegister(RC);
1700   Register Scratch = RegInfo.createVirtualRegister(RC);
1701   Register Scratch2 = RegInfo.createVirtualRegister(RC);
1702   Register Scratch3 = RegInfo.createVirtualRegister(RC);
1703 
1704   unsigned AtomicOp = 0;
1705   bool NeedsAdditionalReg = false;
1706   switch (MI.getOpcode()) {
1707   case Mips::ATOMIC_LOAD_NAND_I8:
1708     AtomicOp = Mips::ATOMIC_LOAD_NAND_I8_POSTRA;
1709     break;
1710   case Mips::ATOMIC_LOAD_NAND_I16:
1711     AtomicOp = Mips::ATOMIC_LOAD_NAND_I16_POSTRA;
1712     break;
1713   case Mips::ATOMIC_SWAP_I8:
1714     AtomicOp = Mips::ATOMIC_SWAP_I8_POSTRA;
1715     break;
1716   case Mips::ATOMIC_SWAP_I16:
1717     AtomicOp = Mips::ATOMIC_SWAP_I16_POSTRA;
1718     break;
1719   case Mips::ATOMIC_LOAD_ADD_I8:
1720     AtomicOp = Mips::ATOMIC_LOAD_ADD_I8_POSTRA;
1721     break;
1722   case Mips::ATOMIC_LOAD_ADD_I16:
1723     AtomicOp = Mips::ATOMIC_LOAD_ADD_I16_POSTRA;
1724     break;
1725   case Mips::ATOMIC_LOAD_SUB_I8:
1726     AtomicOp = Mips::ATOMIC_LOAD_SUB_I8_POSTRA;
1727     break;
1728   case Mips::ATOMIC_LOAD_SUB_I16:
1729     AtomicOp = Mips::ATOMIC_LOAD_SUB_I16_POSTRA;
1730     break;
1731   case Mips::ATOMIC_LOAD_AND_I8:
1732     AtomicOp = Mips::ATOMIC_LOAD_AND_I8_POSTRA;
1733     break;
1734   case Mips::ATOMIC_LOAD_AND_I16:
1735     AtomicOp = Mips::ATOMIC_LOAD_AND_I16_POSTRA;
1736     break;
1737   case Mips::ATOMIC_LOAD_OR_I8:
1738     AtomicOp = Mips::ATOMIC_LOAD_OR_I8_POSTRA;
1739     break;
1740   case Mips::ATOMIC_LOAD_OR_I16:
1741     AtomicOp = Mips::ATOMIC_LOAD_OR_I16_POSTRA;
1742     break;
1743   case Mips::ATOMIC_LOAD_XOR_I8:
1744     AtomicOp = Mips::ATOMIC_LOAD_XOR_I8_POSTRA;
1745     break;
1746   case Mips::ATOMIC_LOAD_XOR_I16:
1747     AtomicOp = Mips::ATOMIC_LOAD_XOR_I16_POSTRA;
1748     break;
1749   case Mips::ATOMIC_LOAD_MIN_I8:
1750     AtomicOp = Mips::ATOMIC_LOAD_MIN_I8_POSTRA;
1751     NeedsAdditionalReg = true;
1752     break;
1753   case Mips::ATOMIC_LOAD_MIN_I16:
1754     AtomicOp = Mips::ATOMIC_LOAD_MIN_I16_POSTRA;
1755     NeedsAdditionalReg = true;
1756     break;
1757   case Mips::ATOMIC_LOAD_MAX_I8:
1758     AtomicOp = Mips::ATOMIC_LOAD_MAX_I8_POSTRA;
1759     NeedsAdditionalReg = true;
1760     break;
1761   case Mips::ATOMIC_LOAD_MAX_I16:
1762     AtomicOp = Mips::ATOMIC_LOAD_MAX_I16_POSTRA;
1763     NeedsAdditionalReg = true;
1764     break;
1765   case Mips::ATOMIC_LOAD_UMIN_I8:
1766     AtomicOp = Mips::ATOMIC_LOAD_UMIN_I8_POSTRA;
1767     NeedsAdditionalReg = true;
1768     break;
1769   case Mips::ATOMIC_LOAD_UMIN_I16:
1770     AtomicOp = Mips::ATOMIC_LOAD_UMIN_I16_POSTRA;
1771     NeedsAdditionalReg = true;
1772     break;
1773   case Mips::ATOMIC_LOAD_UMAX_I8:
1774     AtomicOp = Mips::ATOMIC_LOAD_UMAX_I8_POSTRA;
1775     NeedsAdditionalReg = true;
1776     break;
1777   case Mips::ATOMIC_LOAD_UMAX_I16:
1778     AtomicOp = Mips::ATOMIC_LOAD_UMAX_I16_POSTRA;
1779     NeedsAdditionalReg = true;
1780     break;
1781   default:
1782     llvm_unreachable("Unknown subword atomic pseudo for expansion!");
1783   }
1784 
1785   // insert new blocks after the current block
1786   const BasicBlock *LLVM_BB = BB->getBasicBlock();
1787   MachineBasicBlock *exitMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1788   MachineFunction::iterator It = ++BB->getIterator();
1789   MF->insert(It, exitMBB);
1790 
1791   // Transfer the remainder of BB and its successor edges to exitMBB.
1792   exitMBB->splice(exitMBB->begin(), BB,
1793                   std::next(MachineBasicBlock::iterator(MI)), BB->end());
1794   exitMBB->transferSuccessorsAndUpdatePHIs(BB);
1795 
1796   BB->addSuccessor(exitMBB, BranchProbability::getOne());
1797 
1798   //  thisMBB:
1799   //    addiu   masklsb2,$0,-4                # 0xfffffffc
1800   //    and     alignedaddr,ptr,masklsb2
1801   //    andi    ptrlsb2,ptr,3
1802   //    sll     shiftamt,ptrlsb2,3
1803   //    ori     maskupper,$0,255               # 0xff
1804   //    sll     mask,maskupper,shiftamt
1805   //    nor     mask2,$0,mask
1806   //    sll     incr2,incr,shiftamt
1807 
1808   int64_t MaskImm = (Size == 1) ? 255 : 65535;
1809   BuildMI(BB, DL, TII->get(ABI.GetPtrAddiuOp()), MaskLSB2)
1810     .addReg(ABI.GetNullPtr()).addImm(-4);
1811   BuildMI(BB, DL, TII->get(ABI.GetPtrAndOp()), AlignedAddr)
1812     .addReg(Ptr).addReg(MaskLSB2);
1813   BuildMI(BB, DL, TII->get(Mips::ANDi), PtrLSB2)
1814       .addReg(Ptr, 0, ArePtrs64bit ? Mips::sub_32 : 0).addImm(3);
1815   if (Subtarget.isLittle()) {
1816     BuildMI(BB, DL, TII->get(Mips::SLL), ShiftAmt).addReg(PtrLSB2).addImm(3);
1817   } else {
1818     Register Off = RegInfo.createVirtualRegister(RC);
1819     BuildMI(BB, DL, TII->get(Mips::XORi), Off)
1820       .addReg(PtrLSB2).addImm((Size == 1) ? 3 : 2);
1821     BuildMI(BB, DL, TII->get(Mips::SLL), ShiftAmt).addReg(Off).addImm(3);
1822   }
1823   BuildMI(BB, DL, TII->get(Mips::ORi), MaskUpper)
1824     .addReg(Mips::ZERO).addImm(MaskImm);
1825   BuildMI(BB, DL, TII->get(Mips::SLLV), Mask)
1826     .addReg(MaskUpper).addReg(ShiftAmt);
1827   BuildMI(BB, DL, TII->get(Mips::NOR), Mask2).addReg(Mips::ZERO).addReg(Mask);
1828   BuildMI(BB, DL, TII->get(Mips::SLLV), Incr2).addReg(Incr).addReg(ShiftAmt);
1829 
1830 
1831   // The purposes of the flags on the scratch registers is explained in
1832   // emitAtomicBinary. In summary, we need a scratch register which is going to
1833   // be undef, that is unique among registers chosen for the instruction.
1834 
1835   MachineInstrBuilder MIB =
1836       BuildMI(BB, DL, TII->get(AtomicOp))
1837           .addReg(Dest, RegState::Define | RegState::EarlyClobber)
1838           .addReg(AlignedAddr)
1839           .addReg(Incr2)
1840           .addReg(Mask)
1841           .addReg(Mask2)
1842           .addReg(ShiftAmt)
1843           .addReg(Scratch, RegState::EarlyClobber | RegState::Define |
1844                                RegState::Dead | RegState::Implicit)
1845           .addReg(Scratch2, RegState::EarlyClobber | RegState::Define |
1846                                 RegState::Dead | RegState::Implicit)
1847           .addReg(Scratch3, RegState::EarlyClobber | RegState::Define |
1848                                 RegState::Dead | RegState::Implicit);
1849   if (NeedsAdditionalReg) {
1850     Register Scratch4 = RegInfo.createVirtualRegister(RC);
1851     MIB.addReg(Scratch4, RegState::EarlyClobber | RegState::Define |
1852                              RegState::Dead | RegState::Implicit);
1853   }
1854 
1855   MI.eraseFromParent(); // The instruction is gone now.
1856 
1857   return exitMBB;
1858 }
1859 
1860 // Lower atomic compare and swap to a pseudo instruction, taking care to
1861 // define a scratch register for the pseudo instruction's expansion. The
1862 // instruction is expanded after the register allocator as to prevent
1863 // the insertion of stores between the linked load and the store conditional.
1864 
1865 MachineBasicBlock *
emitAtomicCmpSwap(MachineInstr & MI,MachineBasicBlock * BB) const1866 MipsTargetLowering::emitAtomicCmpSwap(MachineInstr &MI,
1867                                       MachineBasicBlock *BB) const {
1868 
1869   assert((MI.getOpcode() == Mips::ATOMIC_CMP_SWAP_I32 ||
1870           MI.getOpcode() == Mips::ATOMIC_CMP_SWAP_I64) &&
1871          "Unsupported atomic pseudo for EmitAtomicCmpSwap.");
1872 
1873   const unsigned Size = MI.getOpcode() == Mips::ATOMIC_CMP_SWAP_I32 ? 4 : 8;
1874 
1875   MachineFunction *MF = BB->getParent();
1876   MachineRegisterInfo &MRI = MF->getRegInfo();
1877   const TargetRegisterClass *RC = getRegClassFor(MVT::getIntegerVT(Size * 8));
1878   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
1879   DebugLoc DL = MI.getDebugLoc();
1880 
1881   unsigned AtomicOp = MI.getOpcode() == Mips::ATOMIC_CMP_SWAP_I32
1882                           ? Mips::ATOMIC_CMP_SWAP_I32_POSTRA
1883                           : Mips::ATOMIC_CMP_SWAP_I64_POSTRA;
1884   Register Dest = MI.getOperand(0).getReg();
1885   Register Ptr = MI.getOperand(1).getReg();
1886   Register OldVal = MI.getOperand(2).getReg();
1887   Register NewVal = MI.getOperand(3).getReg();
1888 
1889   Register Scratch = MRI.createVirtualRegister(RC);
1890   MachineBasicBlock::iterator II(MI);
1891 
1892   // We need to create copies of the various registers and kill them at the
1893   // atomic pseudo. If the copies are not made, when the atomic is expanded
1894   // after fast register allocation, the spills will end up outside of the
1895   // blocks that their values are defined in, causing livein errors.
1896 
1897   Register PtrCopy = MRI.createVirtualRegister(MRI.getRegClass(Ptr));
1898   Register OldValCopy = MRI.createVirtualRegister(MRI.getRegClass(OldVal));
1899   Register NewValCopy = MRI.createVirtualRegister(MRI.getRegClass(NewVal));
1900 
1901   BuildMI(*BB, II, DL, TII->get(Mips::COPY), PtrCopy).addReg(Ptr);
1902   BuildMI(*BB, II, DL, TII->get(Mips::COPY), OldValCopy).addReg(OldVal);
1903   BuildMI(*BB, II, DL, TII->get(Mips::COPY), NewValCopy).addReg(NewVal);
1904 
1905   // The purposes of the flags on the scratch registers is explained in
1906   // emitAtomicBinary. In summary, we need a scratch register which is going to
1907   // be undef, that is unique among registers chosen for the instruction.
1908 
1909   BuildMI(*BB, II, DL, TII->get(AtomicOp))
1910       .addReg(Dest, RegState::Define | RegState::EarlyClobber)
1911       .addReg(PtrCopy, RegState::Kill)
1912       .addReg(OldValCopy, RegState::Kill)
1913       .addReg(NewValCopy, RegState::Kill)
1914       .addReg(Scratch, RegState::EarlyClobber | RegState::Define |
1915                            RegState::Dead | RegState::Implicit);
1916 
1917   MI.eraseFromParent(); // The instruction is gone now.
1918 
1919   return BB;
1920 }
1921 
emitAtomicCmpSwapPartword(MachineInstr & MI,MachineBasicBlock * BB,unsigned Size) const1922 MachineBasicBlock *MipsTargetLowering::emitAtomicCmpSwapPartword(
1923     MachineInstr &MI, MachineBasicBlock *BB, unsigned Size) const {
1924   assert((Size == 1 || Size == 2) &&
1925       "Unsupported size for EmitAtomicCmpSwapPartial.");
1926 
1927   MachineFunction *MF = BB->getParent();
1928   MachineRegisterInfo &RegInfo = MF->getRegInfo();
1929   const TargetRegisterClass *RC = getRegClassFor(MVT::i32);
1930   const bool ArePtrs64bit = ABI.ArePtrs64bit();
1931   const TargetRegisterClass *RCp =
1932     getRegClassFor(ArePtrs64bit ? MVT::i64 : MVT::i32);
1933   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
1934   DebugLoc DL = MI.getDebugLoc();
1935 
1936   Register Dest = MI.getOperand(0).getReg();
1937   Register Ptr = MI.getOperand(1).getReg();
1938   Register CmpVal = MI.getOperand(2).getReg();
1939   Register NewVal = MI.getOperand(3).getReg();
1940 
1941   Register AlignedAddr = RegInfo.createVirtualRegister(RCp);
1942   Register ShiftAmt = RegInfo.createVirtualRegister(RC);
1943   Register Mask = RegInfo.createVirtualRegister(RC);
1944   Register Mask2 = RegInfo.createVirtualRegister(RC);
1945   Register ShiftedCmpVal = RegInfo.createVirtualRegister(RC);
1946   Register ShiftedNewVal = RegInfo.createVirtualRegister(RC);
1947   Register MaskLSB2 = RegInfo.createVirtualRegister(RCp);
1948   Register PtrLSB2 = RegInfo.createVirtualRegister(RC);
1949   Register MaskUpper = RegInfo.createVirtualRegister(RC);
1950   Register MaskedCmpVal = RegInfo.createVirtualRegister(RC);
1951   Register MaskedNewVal = RegInfo.createVirtualRegister(RC);
1952   unsigned AtomicOp = MI.getOpcode() == Mips::ATOMIC_CMP_SWAP_I8
1953                           ? Mips::ATOMIC_CMP_SWAP_I8_POSTRA
1954                           : Mips::ATOMIC_CMP_SWAP_I16_POSTRA;
1955 
1956   // The scratch registers here with the EarlyClobber | Define | Dead | Implicit
1957   // flags are used to coerce the register allocator and the machine verifier to
1958   // accept the usage of these registers.
1959   // The EarlyClobber flag has the semantic properties that the operand it is
1960   // attached to is clobbered before the rest of the inputs are read. Hence it
1961   // must be unique among the operands to the instruction.
1962   // The Define flag is needed to coerce the machine verifier that an Undef
1963   // value isn't a problem.
1964   // The Dead flag is needed as the value in scratch isn't used by any other
1965   // instruction. Kill isn't used as Dead is more precise.
1966   Register Scratch = RegInfo.createVirtualRegister(RC);
1967   Register Scratch2 = RegInfo.createVirtualRegister(RC);
1968 
1969   // insert new blocks after the current block
1970   const BasicBlock *LLVM_BB = BB->getBasicBlock();
1971   MachineBasicBlock *exitMBB = MF->CreateMachineBasicBlock(LLVM_BB);
1972   MachineFunction::iterator It = ++BB->getIterator();
1973   MF->insert(It, exitMBB);
1974 
1975   // Transfer the remainder of BB and its successor edges to exitMBB.
1976   exitMBB->splice(exitMBB->begin(), BB,
1977                   std::next(MachineBasicBlock::iterator(MI)), BB->end());
1978   exitMBB->transferSuccessorsAndUpdatePHIs(BB);
1979 
1980   BB->addSuccessor(exitMBB, BranchProbability::getOne());
1981 
1982   //  thisMBB:
1983   //    addiu   masklsb2,$0,-4                # 0xfffffffc
1984   //    and     alignedaddr,ptr,masklsb2
1985   //    andi    ptrlsb2,ptr,3
1986   //    xori    ptrlsb2,ptrlsb2,3              # Only for BE
1987   //    sll     shiftamt,ptrlsb2,3
1988   //    ori     maskupper,$0,255               # 0xff
1989   //    sll     mask,maskupper,shiftamt
1990   //    nor     mask2,$0,mask
1991   //    andi    maskedcmpval,cmpval,255
1992   //    sll     shiftedcmpval,maskedcmpval,shiftamt
1993   //    andi    maskednewval,newval,255
1994   //    sll     shiftednewval,maskednewval,shiftamt
1995   int64_t MaskImm = (Size == 1) ? 255 : 65535;
1996   BuildMI(BB, DL, TII->get(ArePtrs64bit ? Mips::DADDiu : Mips::ADDiu), MaskLSB2)
1997     .addReg(ABI.GetNullPtr()).addImm(-4);
1998   BuildMI(BB, DL, TII->get(ArePtrs64bit ? Mips::AND64 : Mips::AND), AlignedAddr)
1999     .addReg(Ptr).addReg(MaskLSB2);
2000   BuildMI(BB, DL, TII->get(Mips::ANDi), PtrLSB2)
2001       .addReg(Ptr, 0, ArePtrs64bit ? Mips::sub_32 : 0).addImm(3);
2002   if (Subtarget.isLittle()) {
2003     BuildMI(BB, DL, TII->get(Mips::SLL), ShiftAmt).addReg(PtrLSB2).addImm(3);
2004   } else {
2005     Register Off = RegInfo.createVirtualRegister(RC);
2006     BuildMI(BB, DL, TII->get(Mips::XORi), Off)
2007       .addReg(PtrLSB2).addImm((Size == 1) ? 3 : 2);
2008     BuildMI(BB, DL, TII->get(Mips::SLL), ShiftAmt).addReg(Off).addImm(3);
2009   }
2010   BuildMI(BB, DL, TII->get(Mips::ORi), MaskUpper)
2011     .addReg(Mips::ZERO).addImm(MaskImm);
2012   BuildMI(BB, DL, TII->get(Mips::SLLV), Mask)
2013     .addReg(MaskUpper).addReg(ShiftAmt);
2014   BuildMI(BB, DL, TII->get(Mips::NOR), Mask2).addReg(Mips::ZERO).addReg(Mask);
2015   BuildMI(BB, DL, TII->get(Mips::ANDi), MaskedCmpVal)
2016     .addReg(CmpVal).addImm(MaskImm);
2017   BuildMI(BB, DL, TII->get(Mips::SLLV), ShiftedCmpVal)
2018     .addReg(MaskedCmpVal).addReg(ShiftAmt);
2019   BuildMI(BB, DL, TII->get(Mips::ANDi), MaskedNewVal)
2020     .addReg(NewVal).addImm(MaskImm);
2021   BuildMI(BB, DL, TII->get(Mips::SLLV), ShiftedNewVal)
2022     .addReg(MaskedNewVal).addReg(ShiftAmt);
2023 
2024   // The purposes of the flags on the scratch registers are explained in
2025   // emitAtomicBinary. In summary, we need a scratch register which is going to
2026   // be undef, that is unique among the register chosen for the instruction.
2027 
2028   BuildMI(BB, DL, TII->get(AtomicOp))
2029       .addReg(Dest, RegState::Define | RegState::EarlyClobber)
2030       .addReg(AlignedAddr)
2031       .addReg(Mask)
2032       .addReg(ShiftedCmpVal)
2033       .addReg(Mask2)
2034       .addReg(ShiftedNewVal)
2035       .addReg(ShiftAmt)
2036       .addReg(Scratch, RegState::EarlyClobber | RegState::Define |
2037                            RegState::Dead | RegState::Implicit)
2038       .addReg(Scratch2, RegState::EarlyClobber | RegState::Define |
2039                             RegState::Dead | RegState::Implicit);
2040 
2041   MI.eraseFromParent(); // The instruction is gone now.
2042 
2043   return exitMBB;
2044 }
2045 
lowerBRCOND(SDValue Op,SelectionDAG & DAG) const2046 SDValue MipsTargetLowering::lowerBRCOND(SDValue Op, SelectionDAG &DAG) const {
2047   // The first operand is the chain, the second is the condition, the third is
2048   // the block to branch to if the condition is true.
2049   SDValue Chain = Op.getOperand(0);
2050   SDValue Dest = Op.getOperand(2);
2051   SDLoc DL(Op);
2052 
2053   assert(!Subtarget.hasMips32r6() && !Subtarget.hasMips64r6());
2054   SDValue CondRes = createFPCmp(DAG, Op.getOperand(1));
2055 
2056   // Return if flag is not set by a floating point comparison.
2057   if (CondRes.getOpcode() != MipsISD::FPCmp)
2058     return Op;
2059 
2060   SDValue CCNode  = CondRes.getOperand(2);
2061   Mips::CondCode CC = (Mips::CondCode)CCNode->getAsZExtVal();
2062   unsigned Opc = invertFPCondCodeUser(CC) ? Mips::BRANCH_F : Mips::BRANCH_T;
2063   SDValue BrCode = DAG.getConstant(Opc, DL, MVT::i32);
2064   SDValue FCC0 = DAG.getRegister(Mips::FCC0, MVT::i32);
2065   return DAG.getNode(MipsISD::FPBrcond, DL, Op.getValueType(), Chain, BrCode,
2066                      FCC0, Dest, CondRes);
2067 }
2068 
2069 SDValue MipsTargetLowering::
lowerSELECT(SDValue Op,SelectionDAG & DAG) const2070 lowerSELECT(SDValue Op, SelectionDAG &DAG) const
2071 {
2072   assert(!Subtarget.hasMips32r6() && !Subtarget.hasMips64r6());
2073   SDValue Cond = createFPCmp(DAG, Op.getOperand(0));
2074 
2075   // Return if flag is not set by a floating point comparison.
2076   if (Cond.getOpcode() != MipsISD::FPCmp)
2077     return Op;
2078 
2079   return createCMovFP(DAG, Cond, Op.getOperand(1), Op.getOperand(2),
2080                       SDLoc(Op));
2081 }
2082 
lowerSETCC(SDValue Op,SelectionDAG & DAG) const2083 SDValue MipsTargetLowering::lowerSETCC(SDValue Op, SelectionDAG &DAG) const {
2084   assert(!Subtarget.hasMips32r6() && !Subtarget.hasMips64r6());
2085   SDValue Cond = createFPCmp(DAG, Op);
2086 
2087   assert(Cond.getOpcode() == MipsISD::FPCmp &&
2088          "Floating point operand expected.");
2089 
2090   SDLoc DL(Op);
2091   SDValue True  = DAG.getConstant(1, DL, MVT::i32);
2092   SDValue False = DAG.getConstant(0, DL, MVT::i32);
2093 
2094   return createCMovFP(DAG, Cond, True, False, DL);
2095 }
2096 
lowerGlobalAddress(SDValue Op,SelectionDAG & DAG) const2097 SDValue MipsTargetLowering::lowerGlobalAddress(SDValue Op,
2098                                                SelectionDAG &DAG) const {
2099   EVT Ty = Op.getValueType();
2100   GlobalAddressSDNode *N = cast<GlobalAddressSDNode>(Op);
2101   const GlobalValue *GV = N->getGlobal();
2102 
2103   if (!isPositionIndependent()) {
2104     const MipsTargetObjectFile *TLOF =
2105         static_cast<const MipsTargetObjectFile *>(
2106             getTargetMachine().getObjFileLowering());
2107     const GlobalObject *GO = GV->getAliaseeObject();
2108     if (GO && TLOF->IsGlobalInSmallSection(GO, getTargetMachine()))
2109       // %gp_rel relocation
2110       return getAddrGPRel(N, SDLoc(N), Ty, DAG, ABI.IsN64());
2111 
2112                                 // %hi/%lo relocation
2113     return Subtarget.hasSym32() ? getAddrNonPIC(N, SDLoc(N), Ty, DAG)
2114                                 // %highest/%higher/%hi/%lo relocation
2115                                 : getAddrNonPICSym64(N, SDLoc(N), Ty, DAG);
2116   }
2117 
2118   // Every other architecture would use shouldAssumeDSOLocal in here, but
2119   // mips is special.
2120   // * In PIC code mips requires got loads even for local statics!
2121   // * To save on got entries, for local statics the got entry contains the
2122   //   page and an additional add instruction takes care of the low bits.
2123   // * It is legal to access a hidden symbol with a non hidden undefined,
2124   //   so one cannot guarantee that all access to a hidden symbol will know
2125   //   it is hidden.
2126   // * Mips linkers don't support creating a page and a full got entry for
2127   //   the same symbol.
2128   // * Given all that, we have to use a full got entry for hidden symbols :-(
2129   if (GV->hasLocalLinkage())
2130     return getAddrLocal(N, SDLoc(N), Ty, DAG, ABI.IsN32() || ABI.IsN64());
2131 
2132   if (Subtarget.useXGOT())
2133     return getAddrGlobalLargeGOT(
2134         N, SDLoc(N), Ty, DAG, MipsII::MO_GOT_HI16, MipsII::MO_GOT_LO16,
2135         DAG.getEntryNode(),
2136         MachinePointerInfo::getGOT(DAG.getMachineFunction()));
2137 
2138   return getAddrGlobal(
2139       N, SDLoc(N), Ty, DAG,
2140       (ABI.IsN32() || ABI.IsN64()) ? MipsII::MO_GOT_DISP : MipsII::MO_GOT,
2141       DAG.getEntryNode(), MachinePointerInfo::getGOT(DAG.getMachineFunction()));
2142 }
2143 
lowerBlockAddress(SDValue Op,SelectionDAG & DAG) const2144 SDValue MipsTargetLowering::lowerBlockAddress(SDValue Op,
2145                                               SelectionDAG &DAG) const {
2146   BlockAddressSDNode *N = cast<BlockAddressSDNode>(Op);
2147   EVT Ty = Op.getValueType();
2148 
2149   if (!isPositionIndependent())
2150     return Subtarget.hasSym32() ? getAddrNonPIC(N, SDLoc(N), Ty, DAG)
2151                                 : getAddrNonPICSym64(N, SDLoc(N), Ty, DAG);
2152 
2153   return getAddrLocal(N, SDLoc(N), Ty, DAG, ABI.IsN32() || ABI.IsN64());
2154 }
2155 
2156 SDValue MipsTargetLowering::
lowerGlobalTLSAddress(SDValue Op,SelectionDAG & DAG) const2157 lowerGlobalTLSAddress(SDValue Op, SelectionDAG &DAG) const
2158 {
2159   // If the relocation model is PIC, use the General Dynamic TLS Model or
2160   // Local Dynamic TLS model, otherwise use the Initial Exec or
2161   // Local Exec TLS Model.
2162 
2163   GlobalAddressSDNode *GA = cast<GlobalAddressSDNode>(Op);
2164   if (DAG.getTarget().useEmulatedTLS())
2165     return LowerToTLSEmulatedModel(GA, DAG);
2166 
2167   SDLoc DL(GA);
2168   const GlobalValue *GV = GA->getGlobal();
2169   EVT PtrVT = getPointerTy(DAG.getDataLayout());
2170 
2171   TLSModel::Model model = getTargetMachine().getTLSModel(GV);
2172 
2173   if (model == TLSModel::GeneralDynamic || model == TLSModel::LocalDynamic) {
2174     // General Dynamic and Local Dynamic TLS Model.
2175     unsigned Flag = (model == TLSModel::LocalDynamic) ? MipsII::MO_TLSLDM
2176                                                       : MipsII::MO_TLSGD;
2177 
2178     SDValue TGA = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0, Flag);
2179     SDValue Argument = DAG.getNode(MipsISD::Wrapper, DL, PtrVT,
2180                                    getGlobalReg(DAG, PtrVT), TGA);
2181     unsigned PtrSize = PtrVT.getSizeInBits();
2182     IntegerType *PtrTy = Type::getIntNTy(*DAG.getContext(), PtrSize);
2183 
2184     SDValue TlsGetAddr = DAG.getExternalSymbol("__tls_get_addr", PtrVT);
2185 
2186     ArgListTy Args;
2187     ArgListEntry Entry;
2188     Entry.Node = Argument;
2189     Entry.Ty = PtrTy;
2190     Args.push_back(Entry);
2191 
2192     TargetLowering::CallLoweringInfo CLI(DAG);
2193     CLI.setDebugLoc(DL)
2194         .setChain(DAG.getEntryNode())
2195         .setLibCallee(CallingConv::C, PtrTy, TlsGetAddr, std::move(Args));
2196     std::pair<SDValue, SDValue> CallResult = LowerCallTo(CLI);
2197 
2198     SDValue Ret = CallResult.first;
2199 
2200     if (model != TLSModel::LocalDynamic)
2201       return Ret;
2202 
2203     SDValue TGAHi = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0,
2204                                                MipsII::MO_DTPREL_HI);
2205     SDValue Hi = DAG.getNode(MipsISD::TlsHi, DL, PtrVT, TGAHi);
2206     SDValue TGALo = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0,
2207                                                MipsII::MO_DTPREL_LO);
2208     SDValue Lo = DAG.getNode(MipsISD::Lo, DL, PtrVT, TGALo);
2209     SDValue Add = DAG.getNode(ISD::ADD, DL, PtrVT, Hi, Ret);
2210     return DAG.getNode(ISD::ADD, DL, PtrVT, Add, Lo);
2211   }
2212 
2213   SDValue Offset;
2214   if (model == TLSModel::InitialExec) {
2215     // Initial Exec TLS Model
2216     SDValue TGA = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0,
2217                                              MipsII::MO_GOTTPREL);
2218     TGA = DAG.getNode(MipsISD::Wrapper, DL, PtrVT, getGlobalReg(DAG, PtrVT),
2219                       TGA);
2220     Offset =
2221         DAG.getLoad(PtrVT, DL, DAG.getEntryNode(), TGA, MachinePointerInfo());
2222   } else {
2223     // Local Exec TLS Model
2224     assert(model == TLSModel::LocalExec);
2225     SDValue TGAHi = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0,
2226                                                MipsII::MO_TPREL_HI);
2227     SDValue TGALo = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0,
2228                                                MipsII::MO_TPREL_LO);
2229     SDValue Hi = DAG.getNode(MipsISD::TlsHi, DL, PtrVT, TGAHi);
2230     SDValue Lo = DAG.getNode(MipsISD::Lo, DL, PtrVT, TGALo);
2231     Offset = DAG.getNode(ISD::ADD, DL, PtrVT, Hi, Lo);
2232   }
2233 
2234   SDValue ThreadPointer = DAG.getNode(MipsISD::ThreadPointer, DL, PtrVT);
2235   return DAG.getNode(ISD::ADD, DL, PtrVT, ThreadPointer, Offset);
2236 }
2237 
2238 SDValue MipsTargetLowering::
lowerJumpTable(SDValue Op,SelectionDAG & DAG) const2239 lowerJumpTable(SDValue Op, SelectionDAG &DAG) const
2240 {
2241   JumpTableSDNode *N = cast<JumpTableSDNode>(Op);
2242   EVT Ty = Op.getValueType();
2243 
2244   if (!isPositionIndependent())
2245     return Subtarget.hasSym32() ? getAddrNonPIC(N, SDLoc(N), Ty, DAG)
2246                                 : getAddrNonPICSym64(N, SDLoc(N), Ty, DAG);
2247 
2248   return getAddrLocal(N, SDLoc(N), Ty, DAG, ABI.IsN32() || ABI.IsN64());
2249 }
2250 
2251 SDValue MipsTargetLowering::
lowerConstantPool(SDValue Op,SelectionDAG & DAG) const2252 lowerConstantPool(SDValue Op, SelectionDAG &DAG) const
2253 {
2254   ConstantPoolSDNode *N = cast<ConstantPoolSDNode>(Op);
2255   EVT Ty = Op.getValueType();
2256 
2257   if (!isPositionIndependent()) {
2258     const MipsTargetObjectFile *TLOF =
2259         static_cast<const MipsTargetObjectFile *>(
2260             getTargetMachine().getObjFileLowering());
2261 
2262     if (TLOF->IsConstantInSmallSection(DAG.getDataLayout(), N->getConstVal(),
2263                                        getTargetMachine()))
2264       // %gp_rel relocation
2265       return getAddrGPRel(N, SDLoc(N), Ty, DAG, ABI.IsN64());
2266 
2267     return Subtarget.hasSym32() ? getAddrNonPIC(N, SDLoc(N), Ty, DAG)
2268                                 : getAddrNonPICSym64(N, SDLoc(N), Ty, DAG);
2269   }
2270 
2271  return getAddrLocal(N, SDLoc(N), Ty, DAG, ABI.IsN32() || ABI.IsN64());
2272 }
2273 
lowerVASTART(SDValue Op,SelectionDAG & DAG) const2274 SDValue MipsTargetLowering::lowerVASTART(SDValue Op, SelectionDAG &DAG) const {
2275   MachineFunction &MF = DAG.getMachineFunction();
2276   MipsFunctionInfo *FuncInfo = MF.getInfo<MipsFunctionInfo>();
2277 
2278   SDLoc DL(Op);
2279   SDValue FI = DAG.getFrameIndex(FuncInfo->getVarArgsFrameIndex(),
2280                                  getPointerTy(MF.getDataLayout()));
2281 
2282   // vastart just stores the address of the VarArgsFrameIndex slot into the
2283   // memory location argument.
2284   const Value *SV = cast<SrcValueSDNode>(Op.getOperand(2))->getValue();
2285   return DAG.getStore(Op.getOperand(0), DL, FI, Op.getOperand(1),
2286                       MachinePointerInfo(SV));
2287 }
2288 
lowerVAARG(SDValue Op,SelectionDAG & DAG) const2289 SDValue MipsTargetLowering::lowerVAARG(SDValue Op, SelectionDAG &DAG) const {
2290   SDNode *Node = Op.getNode();
2291   EVT VT = Node->getValueType(0);
2292   SDValue Chain = Node->getOperand(0);
2293   SDValue VAListPtr = Node->getOperand(1);
2294   const Align Align =
2295       llvm::MaybeAlign(Node->getConstantOperandVal(3)).valueOrOne();
2296   const Value *SV = cast<SrcValueSDNode>(Node->getOperand(2))->getValue();
2297   SDLoc DL(Node);
2298   unsigned ArgSlotSizeInBytes = (ABI.IsN32() || ABI.IsN64()) ? 8 : 4;
2299 
2300   SDValue VAListLoad = DAG.getLoad(getPointerTy(DAG.getDataLayout()), DL, Chain,
2301                                    VAListPtr, MachinePointerInfo(SV));
2302   SDValue VAList = VAListLoad;
2303 
2304   // Re-align the pointer if necessary.
2305   // It should only ever be necessary for 64-bit types on O32 since the minimum
2306   // argument alignment is the same as the maximum type alignment for N32/N64.
2307   //
2308   // FIXME: We currently align too often. The code generator doesn't notice
2309   //        when the pointer is still aligned from the last va_arg (or pair of
2310   //        va_args for the i64 on O32 case).
2311   if (Align > getMinStackArgumentAlignment()) {
2312     VAList = DAG.getNode(
2313         ISD::ADD, DL, VAList.getValueType(), VAList,
2314         DAG.getConstant(Align.value() - 1, DL, VAList.getValueType()));
2315 
2316     VAList = DAG.getNode(
2317         ISD::AND, DL, VAList.getValueType(), VAList,
2318         DAG.getConstant(-(int64_t)Align.value(), DL, VAList.getValueType()));
2319   }
2320 
2321   // Increment the pointer, VAList, to the next vaarg.
2322   auto &TD = DAG.getDataLayout();
2323   unsigned ArgSizeInBytes =
2324       TD.getTypeAllocSize(VT.getTypeForEVT(*DAG.getContext()));
2325   SDValue Tmp3 =
2326       DAG.getNode(ISD::ADD, DL, VAList.getValueType(), VAList,
2327                   DAG.getConstant(alignTo(ArgSizeInBytes, ArgSlotSizeInBytes),
2328                                   DL, VAList.getValueType()));
2329   // Store the incremented VAList to the legalized pointer
2330   Chain = DAG.getStore(VAListLoad.getValue(1), DL, Tmp3, VAListPtr,
2331                        MachinePointerInfo(SV));
2332 
2333   // In big-endian mode we must adjust the pointer when the load size is smaller
2334   // than the argument slot size. We must also reduce the known alignment to
2335   // match. For example in the N64 ABI, we must add 4 bytes to the offset to get
2336   // the correct half of the slot, and reduce the alignment from 8 (slot
2337   // alignment) down to 4 (type alignment).
2338   if (!Subtarget.isLittle() && ArgSizeInBytes < ArgSlotSizeInBytes) {
2339     unsigned Adjustment = ArgSlotSizeInBytes - ArgSizeInBytes;
2340     VAList = DAG.getNode(ISD::ADD, DL, VAListPtr.getValueType(), VAList,
2341                          DAG.getIntPtrConstant(Adjustment, DL));
2342   }
2343   // Load the actual argument out of the pointer VAList
2344   return DAG.getLoad(VT, DL, Chain, VAList, MachinePointerInfo());
2345 }
2346 
lowerFCOPYSIGN32(SDValue Op,SelectionDAG & DAG,bool HasExtractInsert)2347 static SDValue lowerFCOPYSIGN32(SDValue Op, SelectionDAG &DAG,
2348                                 bool HasExtractInsert) {
2349   EVT TyX = Op.getOperand(0).getValueType();
2350   EVT TyY = Op.getOperand(1).getValueType();
2351   SDLoc DL(Op);
2352   SDValue Const1 = DAG.getConstant(1, DL, MVT::i32);
2353   SDValue Const31 = DAG.getConstant(31, DL, MVT::i32);
2354   SDValue Res;
2355 
2356   // If operand is of type f64, extract the upper 32-bit. Otherwise, bitcast it
2357   // to i32.
2358   SDValue X = (TyX == MVT::f32) ?
2359     DAG.getNode(ISD::BITCAST, DL, MVT::i32, Op.getOperand(0)) :
2360     DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32, Op.getOperand(0),
2361                 Const1);
2362   SDValue Y = (TyY == MVT::f32) ?
2363     DAG.getNode(ISD::BITCAST, DL, MVT::i32, Op.getOperand(1)) :
2364     DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32, Op.getOperand(1),
2365                 Const1);
2366 
2367   if (HasExtractInsert) {
2368     // ext  E, Y, 31, 1  ; extract bit31 of Y
2369     // ins  X, E, 31, 1  ; insert extracted bit at bit31 of X
2370     SDValue E = DAG.getNode(MipsISD::Ext, DL, MVT::i32, Y, Const31, Const1);
2371     Res = DAG.getNode(MipsISD::Ins, DL, MVT::i32, E, Const31, Const1, X);
2372   } else {
2373     // sll SllX, X, 1
2374     // srl SrlX, SllX, 1
2375     // srl SrlY, Y, 31
2376     // sll SllY, SrlX, 31
2377     // or  Or, SrlX, SllY
2378     SDValue SllX = DAG.getNode(ISD::SHL, DL, MVT::i32, X, Const1);
2379     SDValue SrlX = DAG.getNode(ISD::SRL, DL, MVT::i32, SllX, Const1);
2380     SDValue SrlY = DAG.getNode(ISD::SRL, DL, MVT::i32, Y, Const31);
2381     SDValue SllY = DAG.getNode(ISD::SHL, DL, MVT::i32, SrlY, Const31);
2382     Res = DAG.getNode(ISD::OR, DL, MVT::i32, SrlX, SllY);
2383   }
2384 
2385   if (TyX == MVT::f32)
2386     return DAG.getNode(ISD::BITCAST, DL, Op.getOperand(0).getValueType(), Res);
2387 
2388   SDValue LowX = DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32,
2389                              Op.getOperand(0),
2390                              DAG.getConstant(0, DL, MVT::i32));
2391   return DAG.getNode(MipsISD::BuildPairF64, DL, MVT::f64, LowX, Res);
2392 }
2393 
lowerFCOPYSIGN64(SDValue Op,SelectionDAG & DAG,bool HasExtractInsert)2394 static SDValue lowerFCOPYSIGN64(SDValue Op, SelectionDAG &DAG,
2395                                 bool HasExtractInsert) {
2396   unsigned WidthX = Op.getOperand(0).getValueSizeInBits();
2397   unsigned WidthY = Op.getOperand(1).getValueSizeInBits();
2398   EVT TyX = MVT::getIntegerVT(WidthX), TyY = MVT::getIntegerVT(WidthY);
2399   SDLoc DL(Op);
2400   SDValue Const1 = DAG.getConstant(1, DL, MVT::i32);
2401 
2402   // Bitcast to integer nodes.
2403   SDValue X = DAG.getNode(ISD::BITCAST, DL, TyX, Op.getOperand(0));
2404   SDValue Y = DAG.getNode(ISD::BITCAST, DL, TyY, Op.getOperand(1));
2405 
2406   if (HasExtractInsert) {
2407     // ext  E, Y, width(Y) - 1, 1  ; extract bit width(Y)-1 of Y
2408     // ins  X, E, width(X) - 1, 1  ; insert extracted bit at bit width(X)-1 of X
2409     SDValue E = DAG.getNode(MipsISD::Ext, DL, TyY, Y,
2410                             DAG.getConstant(WidthY - 1, DL, MVT::i32), Const1);
2411 
2412     if (WidthX > WidthY)
2413       E = DAG.getNode(ISD::ZERO_EXTEND, DL, TyX, E);
2414     else if (WidthY > WidthX)
2415       E = DAG.getNode(ISD::TRUNCATE, DL, TyX, E);
2416 
2417     SDValue I = DAG.getNode(MipsISD::Ins, DL, TyX, E,
2418                             DAG.getConstant(WidthX - 1, DL, MVT::i32), Const1,
2419                             X);
2420     return DAG.getNode(ISD::BITCAST, DL, Op.getOperand(0).getValueType(), I);
2421   }
2422 
2423   // (d)sll SllX, X, 1
2424   // (d)srl SrlX, SllX, 1
2425   // (d)srl SrlY, Y, width(Y)-1
2426   // (d)sll SllY, SrlX, width(Y)-1
2427   // or     Or, SrlX, SllY
2428   SDValue SllX = DAG.getNode(ISD::SHL, DL, TyX, X, Const1);
2429   SDValue SrlX = DAG.getNode(ISD::SRL, DL, TyX, SllX, Const1);
2430   SDValue SrlY = DAG.getNode(ISD::SRL, DL, TyY, Y,
2431                              DAG.getConstant(WidthY - 1, DL, MVT::i32));
2432 
2433   if (WidthX > WidthY)
2434     SrlY = DAG.getNode(ISD::ZERO_EXTEND, DL, TyX, SrlY);
2435   else if (WidthY > WidthX)
2436     SrlY = DAG.getNode(ISD::TRUNCATE, DL, TyX, SrlY);
2437 
2438   SDValue SllY = DAG.getNode(ISD::SHL, DL, TyX, SrlY,
2439                              DAG.getConstant(WidthX - 1, DL, MVT::i32));
2440   SDValue Or = DAG.getNode(ISD::OR, DL, TyX, SrlX, SllY);
2441   return DAG.getNode(ISD::BITCAST, DL, Op.getOperand(0).getValueType(), Or);
2442 }
2443 
2444 SDValue
lowerFCOPYSIGN(SDValue Op,SelectionDAG & DAG) const2445 MipsTargetLowering::lowerFCOPYSIGN(SDValue Op, SelectionDAG &DAG) const {
2446   if (Subtarget.isGP64bit())
2447     return lowerFCOPYSIGN64(Op, DAG, Subtarget.hasExtractInsert());
2448 
2449   return lowerFCOPYSIGN32(Op, DAG, Subtarget.hasExtractInsert());
2450 }
2451 
lowerFABS32(SDValue Op,SelectionDAG & DAG,bool HasExtractInsert) const2452 SDValue MipsTargetLowering::lowerFABS32(SDValue Op, SelectionDAG &DAG,
2453                                         bool HasExtractInsert) const {
2454   SDLoc DL(Op);
2455   SDValue Res, Const1 = DAG.getConstant(1, DL, MVT::i32);
2456 
2457   if (DAG.getTarget().Options.NoNaNsFPMath || Subtarget.inAbs2008Mode())
2458     return DAG.getNode(MipsISD::FAbs, DL, Op.getValueType(), Op.getOperand(0));
2459 
2460   // If operand is of type f64, extract the upper 32-bit. Otherwise, bitcast it
2461   // to i32.
2462   SDValue X = (Op.getValueType() == MVT::f32)
2463                   ? DAG.getNode(ISD::BITCAST, DL, MVT::i32, Op.getOperand(0))
2464                   : DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32,
2465                                 Op.getOperand(0), Const1);
2466 
2467   // Clear MSB.
2468   if (HasExtractInsert)
2469     Res = DAG.getNode(MipsISD::Ins, DL, MVT::i32,
2470                       DAG.getRegister(Mips::ZERO, MVT::i32),
2471                       DAG.getConstant(31, DL, MVT::i32), Const1, X);
2472   else {
2473     // TODO: Provide DAG patterns which transform (and x, cst)
2474     // back to a (shl (srl x (clz cst)) (clz cst)) sequence.
2475     SDValue SllX = DAG.getNode(ISD::SHL, DL, MVT::i32, X, Const1);
2476     Res = DAG.getNode(ISD::SRL, DL, MVT::i32, SllX, Const1);
2477   }
2478 
2479   if (Op.getValueType() == MVT::f32)
2480     return DAG.getNode(ISD::BITCAST, DL, MVT::f32, Res);
2481 
2482   // FIXME: For mips32r2, the sequence of (BuildPairF64 (ins (ExtractElementF64
2483   // Op 1), $zero, 31 1) (ExtractElementF64 Op 0)) and the Op has one use, we
2484   // should be able to drop the usage of mfc1/mtc1 and rewrite the register in
2485   // place.
2486   SDValue LowX =
2487       DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32, Op.getOperand(0),
2488                   DAG.getConstant(0, DL, MVT::i32));
2489   return DAG.getNode(MipsISD::BuildPairF64, DL, MVT::f64, LowX, Res);
2490 }
2491 
lowerFABS64(SDValue Op,SelectionDAG & DAG,bool HasExtractInsert) const2492 SDValue MipsTargetLowering::lowerFABS64(SDValue Op, SelectionDAG &DAG,
2493                                         bool HasExtractInsert) const {
2494   SDLoc DL(Op);
2495   SDValue Res, Const1 = DAG.getConstant(1, DL, MVT::i32);
2496 
2497   if (DAG.getTarget().Options.NoNaNsFPMath || Subtarget.inAbs2008Mode())
2498     return DAG.getNode(MipsISD::FAbs, DL, Op.getValueType(), Op.getOperand(0));
2499 
2500   // Bitcast to integer node.
2501   SDValue X = DAG.getNode(ISD::BITCAST, DL, MVT::i64, Op.getOperand(0));
2502 
2503   // Clear MSB.
2504   if (HasExtractInsert)
2505     Res = DAG.getNode(MipsISD::Ins, DL, MVT::i64,
2506                       DAG.getRegister(Mips::ZERO_64, MVT::i64),
2507                       DAG.getConstant(63, DL, MVT::i32), Const1, X);
2508   else {
2509     SDValue SllX = DAG.getNode(ISD::SHL, DL, MVT::i64, X, Const1);
2510     Res = DAG.getNode(ISD::SRL, DL, MVT::i64, SllX, Const1);
2511   }
2512 
2513   return DAG.getNode(ISD::BITCAST, DL, MVT::f64, Res);
2514 }
2515 
lowerFABS(SDValue Op,SelectionDAG & DAG) const2516 SDValue MipsTargetLowering::lowerFABS(SDValue Op, SelectionDAG &DAG) const {
2517   if ((ABI.IsN32() || ABI.IsN64()) && (Op.getValueType() == MVT::f64))
2518     return lowerFABS64(Op, DAG, Subtarget.hasExtractInsert());
2519 
2520   return lowerFABS32(Op, DAG, Subtarget.hasExtractInsert());
2521 }
2522 
2523 SDValue MipsTargetLowering::
lowerFRAMEADDR(SDValue Op,SelectionDAG & DAG) const2524 lowerFRAMEADDR(SDValue Op, SelectionDAG &DAG) const {
2525   // check the depth
2526   if (Op.getConstantOperandVal(0) != 0) {
2527     DAG.getContext()->emitError(
2528         "return address can be determined only for current frame");
2529     return SDValue();
2530   }
2531 
2532   MachineFrameInfo &MFI = DAG.getMachineFunction().getFrameInfo();
2533   MFI.setFrameAddressIsTaken(true);
2534   EVT VT = Op.getValueType();
2535   SDLoc DL(Op);
2536   SDValue FrameAddr = DAG.getCopyFromReg(
2537       DAG.getEntryNode(), DL, ABI.IsN64() ? Mips::FP_64 : Mips::FP, VT);
2538   return FrameAddr;
2539 }
2540 
lowerRETURNADDR(SDValue Op,SelectionDAG & DAG) const2541 SDValue MipsTargetLowering::lowerRETURNADDR(SDValue Op,
2542                                             SelectionDAG &DAG) const {
2543   if (verifyReturnAddressArgumentIsConstant(Op, DAG))
2544     return SDValue();
2545 
2546   // check the depth
2547   if (Op.getConstantOperandVal(0) != 0) {
2548     DAG.getContext()->emitError(
2549         "return address can be determined only for current frame");
2550     return SDValue();
2551   }
2552 
2553   MachineFunction &MF = DAG.getMachineFunction();
2554   MachineFrameInfo &MFI = MF.getFrameInfo();
2555   MVT VT = Op.getSimpleValueType();
2556   unsigned RA = ABI.IsN64() ? Mips::RA_64 : Mips::RA;
2557   MFI.setReturnAddressIsTaken(true);
2558 
2559   // Return RA, which contains the return address. Mark it an implicit live-in.
2560   Register Reg = MF.addLiveIn(RA, getRegClassFor(VT));
2561   return DAG.getCopyFromReg(DAG.getEntryNode(), SDLoc(Op), Reg, VT);
2562 }
2563 
2564 // An EH_RETURN is the result of lowering llvm.eh.return which in turn is
2565 // generated from __builtin_eh_return (offset, handler)
2566 // The effect of this is to adjust the stack pointer by "offset"
2567 // and then branch to "handler".
lowerEH_RETURN(SDValue Op,SelectionDAG & DAG) const2568 SDValue MipsTargetLowering::lowerEH_RETURN(SDValue Op, SelectionDAG &DAG)
2569                                                                      const {
2570   MachineFunction &MF = DAG.getMachineFunction();
2571   MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
2572 
2573   MipsFI->setCallsEhReturn();
2574   SDValue Chain     = Op.getOperand(0);
2575   SDValue Offset    = Op.getOperand(1);
2576   SDValue Handler   = Op.getOperand(2);
2577   SDLoc DL(Op);
2578   EVT Ty = ABI.IsN64() ? MVT::i64 : MVT::i32;
2579 
2580   // Store stack offset in V1, store jump target in V0. Glue CopyToReg and
2581   // EH_RETURN nodes, so that instructions are emitted back-to-back.
2582   unsigned OffsetReg = ABI.IsN64() ? Mips::V1_64 : Mips::V1;
2583   unsigned AddrReg = ABI.IsN64() ? Mips::V0_64 : Mips::V0;
2584   Chain = DAG.getCopyToReg(Chain, DL, OffsetReg, Offset, SDValue());
2585   Chain = DAG.getCopyToReg(Chain, DL, AddrReg, Handler, Chain.getValue(1));
2586   return DAG.getNode(MipsISD::EH_RETURN, DL, MVT::Other, Chain,
2587                      DAG.getRegister(OffsetReg, Ty),
2588                      DAG.getRegister(AddrReg, getPointerTy(MF.getDataLayout())),
2589                      Chain.getValue(1));
2590 }
2591 
lowerATOMIC_FENCE(SDValue Op,SelectionDAG & DAG) const2592 SDValue MipsTargetLowering::lowerATOMIC_FENCE(SDValue Op,
2593                                               SelectionDAG &DAG) const {
2594   // FIXME: Need pseudo-fence for 'singlethread' fences
2595   // FIXME: Set SType for weaker fences where supported/appropriate.
2596   unsigned SType = 0;
2597   SDLoc DL(Op);
2598   return DAG.getNode(MipsISD::Sync, DL, MVT::Other, Op.getOperand(0),
2599                      DAG.getConstant(SType, DL, MVT::i32));
2600 }
2601 
lowerShiftLeftParts(SDValue Op,SelectionDAG & DAG) const2602 SDValue MipsTargetLowering::lowerShiftLeftParts(SDValue Op,
2603                                                 SelectionDAG &DAG) const {
2604   SDLoc DL(Op);
2605   MVT VT = Subtarget.isGP64bit() ? MVT::i64 : MVT::i32;
2606 
2607   SDValue Lo = Op.getOperand(0), Hi = Op.getOperand(1);
2608   SDValue Shamt = Op.getOperand(2);
2609   // if shamt < (VT.bits):
2610   //  lo = (shl lo, shamt)
2611   //  hi = (or (shl hi, shamt) (srl (srl lo, 1), (xor shamt, (VT.bits-1))))
2612   // else:
2613   //  lo = 0
2614   //  hi = (shl lo, shamt[4:0])
2615   SDValue Not =
2616       DAG.getNode(ISD::XOR, DL, MVT::i32, Shamt,
2617                   DAG.getConstant(VT.getSizeInBits() - 1, DL, MVT::i32));
2618   SDValue ShiftRight1Lo = DAG.getNode(ISD::SRL, DL, VT, Lo,
2619                                       DAG.getConstant(1, DL, VT));
2620   SDValue ShiftRightLo = DAG.getNode(ISD::SRL, DL, VT, ShiftRight1Lo, Not);
2621   SDValue ShiftLeftHi = DAG.getNode(ISD::SHL, DL, VT, Hi, Shamt);
2622   SDValue Or = DAG.getNode(ISD::OR, DL, VT, ShiftLeftHi, ShiftRightLo);
2623   SDValue ShiftLeftLo = DAG.getNode(ISD::SHL, DL, VT, Lo, Shamt);
2624   SDValue Cond = DAG.getNode(ISD::AND, DL, MVT::i32, Shamt,
2625                              DAG.getConstant(VT.getSizeInBits(), DL, MVT::i32));
2626   Lo = DAG.getNode(ISD::SELECT, DL, VT, Cond,
2627                    DAG.getConstant(0, DL, VT), ShiftLeftLo);
2628   Hi = DAG.getNode(ISD::SELECT, DL, VT, Cond, ShiftLeftLo, Or);
2629 
2630   SDValue Ops[2] = {Lo, Hi};
2631   return DAG.getMergeValues(Ops, DL);
2632 }
2633 
lowerShiftRightParts(SDValue Op,SelectionDAG & DAG,bool IsSRA) const2634 SDValue MipsTargetLowering::lowerShiftRightParts(SDValue Op, SelectionDAG &DAG,
2635                                                  bool IsSRA) const {
2636   SDLoc DL(Op);
2637   SDValue Lo = Op.getOperand(0), Hi = Op.getOperand(1);
2638   SDValue Shamt = Op.getOperand(2);
2639   MVT VT = Subtarget.isGP64bit() ? MVT::i64 : MVT::i32;
2640 
2641   // if shamt < (VT.bits):
2642   //  lo = (or (shl (shl hi, 1), (xor shamt, (VT.bits-1))) (srl lo, shamt))
2643   //  if isSRA:
2644   //    hi = (sra hi, shamt)
2645   //  else:
2646   //    hi = (srl hi, shamt)
2647   // else:
2648   //  if isSRA:
2649   //   lo = (sra hi, shamt[4:0])
2650   //   hi = (sra hi, 31)
2651   //  else:
2652   //   lo = (srl hi, shamt[4:0])
2653   //   hi = 0
2654   SDValue Not =
2655       DAG.getNode(ISD::XOR, DL, MVT::i32, Shamt,
2656                   DAG.getConstant(VT.getSizeInBits() - 1, DL, MVT::i32));
2657   SDValue ShiftLeft1Hi = DAG.getNode(ISD::SHL, DL, VT, Hi,
2658                                      DAG.getConstant(1, DL, VT));
2659   SDValue ShiftLeftHi = DAG.getNode(ISD::SHL, DL, VT, ShiftLeft1Hi, Not);
2660   SDValue ShiftRightLo = DAG.getNode(ISD::SRL, DL, VT, Lo, Shamt);
2661   SDValue Or = DAG.getNode(ISD::OR, DL, VT, ShiftLeftHi, ShiftRightLo);
2662   SDValue ShiftRightHi = DAG.getNode(IsSRA ? ISD::SRA : ISD::SRL,
2663                                      DL, VT, Hi, Shamt);
2664   SDValue Cond = DAG.getNode(ISD::AND, DL, MVT::i32, Shamt,
2665                              DAG.getConstant(VT.getSizeInBits(), DL, MVT::i32));
2666   SDValue Ext = DAG.getNode(ISD::SRA, DL, VT, Hi,
2667                             DAG.getConstant(VT.getSizeInBits() - 1, DL, VT));
2668 
2669   if (!(Subtarget.hasMips4() || Subtarget.hasMips32())) {
2670     SDVTList VTList = DAG.getVTList(VT, VT);
2671     return DAG.getNode(Subtarget.isGP64bit() ? MipsISD::DOUBLE_SELECT_I64
2672                                              : MipsISD::DOUBLE_SELECT_I,
2673                        DL, VTList, Cond, ShiftRightHi,
2674                        IsSRA ? Ext : DAG.getConstant(0, DL, VT), Or,
2675                        ShiftRightHi);
2676   }
2677 
2678   Lo = DAG.getNode(ISD::SELECT, DL, VT, Cond, ShiftRightHi, Or);
2679   Hi = DAG.getNode(ISD::SELECT, DL, VT, Cond,
2680                    IsSRA ? Ext : DAG.getConstant(0, DL, VT), ShiftRightHi);
2681 
2682   SDValue Ops[2] = {Lo, Hi};
2683   return DAG.getMergeValues(Ops, DL);
2684 }
2685 
createLoadLR(unsigned Opc,SelectionDAG & DAG,LoadSDNode * LD,SDValue Chain,SDValue Src,unsigned Offset)2686 static SDValue createLoadLR(unsigned Opc, SelectionDAG &DAG, LoadSDNode *LD,
2687                             SDValue Chain, SDValue Src, unsigned Offset) {
2688   SDValue Ptr = LD->getBasePtr();
2689   EVT VT = LD->getValueType(0), MemVT = LD->getMemoryVT();
2690   EVT BasePtrVT = Ptr.getValueType();
2691   SDLoc DL(LD);
2692   SDVTList VTList = DAG.getVTList(VT, MVT::Other);
2693 
2694   if (Offset)
2695     Ptr = DAG.getNode(ISD::ADD, DL, BasePtrVT, Ptr,
2696                       DAG.getConstant(Offset, DL, BasePtrVT));
2697 
2698   SDValue Ops[] = { Chain, Ptr, Src };
2699   return DAG.getMemIntrinsicNode(Opc, DL, VTList, Ops, MemVT,
2700                                  LD->getMemOperand());
2701 }
2702 
2703 // Expand an unaligned 32 or 64-bit integer load node.
lowerLOAD(SDValue Op,SelectionDAG & DAG) const2704 SDValue MipsTargetLowering::lowerLOAD(SDValue Op, SelectionDAG &DAG) const {
2705   LoadSDNode *LD = cast<LoadSDNode>(Op);
2706   EVT MemVT = LD->getMemoryVT();
2707 
2708   if (Subtarget.systemSupportsUnalignedAccess())
2709     return Op;
2710 
2711   // Return if load is aligned or if MemVT is neither i32 nor i64.
2712   if ((LD->getAlign().value() >= (MemVT.getSizeInBits() / 8)) ||
2713       ((MemVT != MVT::i32) && (MemVT != MVT::i64)))
2714     return SDValue();
2715 
2716   bool IsLittle = Subtarget.isLittle();
2717   EVT VT = Op.getValueType();
2718   ISD::LoadExtType ExtType = LD->getExtensionType();
2719   SDValue Chain = LD->getChain(), Undef = DAG.getUNDEF(VT);
2720 
2721   assert((VT == MVT::i32) || (VT == MVT::i64));
2722 
2723   // Expand
2724   //  (set dst, (i64 (load baseptr)))
2725   // to
2726   //  (set tmp, (ldl (add baseptr, 7), undef))
2727   //  (set dst, (ldr baseptr, tmp))
2728   if ((VT == MVT::i64) && (ExtType == ISD::NON_EXTLOAD)) {
2729     SDValue LDL = createLoadLR(MipsISD::LDL, DAG, LD, Chain, Undef,
2730                                IsLittle ? 7 : 0);
2731     return createLoadLR(MipsISD::LDR, DAG, LD, LDL.getValue(1), LDL,
2732                         IsLittle ? 0 : 7);
2733   }
2734 
2735   SDValue LWL = createLoadLR(MipsISD::LWL, DAG, LD, Chain, Undef,
2736                              IsLittle ? 3 : 0);
2737   SDValue LWR = createLoadLR(MipsISD::LWR, DAG, LD, LWL.getValue(1), LWL,
2738                              IsLittle ? 0 : 3);
2739 
2740   // Expand
2741   //  (set dst, (i32 (load baseptr))) or
2742   //  (set dst, (i64 (sextload baseptr))) or
2743   //  (set dst, (i64 (extload baseptr)))
2744   // to
2745   //  (set tmp, (lwl (add baseptr, 3), undef))
2746   //  (set dst, (lwr baseptr, tmp))
2747   if ((VT == MVT::i32) || (ExtType == ISD::SEXTLOAD) ||
2748       (ExtType == ISD::EXTLOAD))
2749     return LWR;
2750 
2751   assert((VT == MVT::i64) && (ExtType == ISD::ZEXTLOAD));
2752 
2753   // Expand
2754   //  (set dst, (i64 (zextload baseptr)))
2755   // to
2756   //  (set tmp0, (lwl (add baseptr, 3), undef))
2757   //  (set tmp1, (lwr baseptr, tmp0))
2758   //  (set tmp2, (shl tmp1, 32))
2759   //  (set dst, (srl tmp2, 32))
2760   SDLoc DL(LD);
2761   SDValue Const32 = DAG.getConstant(32, DL, MVT::i32);
2762   SDValue SLL = DAG.getNode(ISD::SHL, DL, MVT::i64, LWR, Const32);
2763   SDValue SRL = DAG.getNode(ISD::SRL, DL, MVT::i64, SLL, Const32);
2764   SDValue Ops[] = { SRL, LWR.getValue(1) };
2765   return DAG.getMergeValues(Ops, DL);
2766 }
2767 
createStoreLR(unsigned Opc,SelectionDAG & DAG,StoreSDNode * SD,SDValue Chain,unsigned Offset)2768 static SDValue createStoreLR(unsigned Opc, SelectionDAG &DAG, StoreSDNode *SD,
2769                              SDValue Chain, unsigned Offset) {
2770   SDValue Ptr = SD->getBasePtr(), Value = SD->getValue();
2771   EVT MemVT = SD->getMemoryVT(), BasePtrVT = Ptr.getValueType();
2772   SDLoc DL(SD);
2773   SDVTList VTList = DAG.getVTList(MVT::Other);
2774 
2775   if (Offset)
2776     Ptr = DAG.getNode(ISD::ADD, DL, BasePtrVT, Ptr,
2777                       DAG.getConstant(Offset, DL, BasePtrVT));
2778 
2779   SDValue Ops[] = { Chain, Value, Ptr };
2780   return DAG.getMemIntrinsicNode(Opc, DL, VTList, Ops, MemVT,
2781                                  SD->getMemOperand());
2782 }
2783 
2784 // Expand an unaligned 32 or 64-bit integer store node.
lowerUnalignedIntStore(StoreSDNode * SD,SelectionDAG & DAG,bool IsLittle)2785 static SDValue lowerUnalignedIntStore(StoreSDNode *SD, SelectionDAG &DAG,
2786                                       bool IsLittle) {
2787   SDValue Value = SD->getValue(), Chain = SD->getChain();
2788   EVT VT = Value.getValueType();
2789 
2790   // Expand
2791   //  (store val, baseptr) or
2792   //  (truncstore val, baseptr)
2793   // to
2794   //  (swl val, (add baseptr, 3))
2795   //  (swr val, baseptr)
2796   if ((VT == MVT::i32) || SD->isTruncatingStore()) {
2797     SDValue SWL = createStoreLR(MipsISD::SWL, DAG, SD, Chain,
2798                                 IsLittle ? 3 : 0);
2799     return createStoreLR(MipsISD::SWR, DAG, SD, SWL, IsLittle ? 0 : 3);
2800   }
2801 
2802   assert(VT == MVT::i64);
2803 
2804   // Expand
2805   //  (store val, baseptr)
2806   // to
2807   //  (sdl val, (add baseptr, 7))
2808   //  (sdr val, baseptr)
2809   SDValue SDL = createStoreLR(MipsISD::SDL, DAG, SD, Chain, IsLittle ? 7 : 0);
2810   return createStoreLR(MipsISD::SDR, DAG, SD, SDL, IsLittle ? 0 : 7);
2811 }
2812 
2813 // Lower (store (fp_to_sint $fp) $ptr) to (store (TruncIntFP $fp), $ptr).
lowerFP_TO_SINT_STORE(StoreSDNode * SD,SelectionDAG & DAG,bool SingleFloat)2814 static SDValue lowerFP_TO_SINT_STORE(StoreSDNode *SD, SelectionDAG &DAG,
2815                                      bool SingleFloat) {
2816   SDValue Val = SD->getValue();
2817 
2818   if (Val.getOpcode() != ISD::FP_TO_SINT ||
2819       (Val.getValueSizeInBits() > 32 && SingleFloat))
2820     return SDValue();
2821 
2822   EVT FPTy = EVT::getFloatingPointVT(Val.getValueSizeInBits());
2823   SDValue Tr = DAG.getNode(MipsISD::TruncIntFP, SDLoc(Val), FPTy,
2824                            Val.getOperand(0));
2825   return DAG.getStore(SD->getChain(), SDLoc(SD), Tr, SD->getBasePtr(),
2826                       SD->getPointerInfo(), SD->getAlign(),
2827                       SD->getMemOperand()->getFlags());
2828 }
2829 
lowerSTORE(SDValue Op,SelectionDAG & DAG) const2830 SDValue MipsTargetLowering::lowerSTORE(SDValue Op, SelectionDAG &DAG) const {
2831   StoreSDNode *SD = cast<StoreSDNode>(Op);
2832   EVT MemVT = SD->getMemoryVT();
2833 
2834   // Lower unaligned integer stores.
2835   if (!Subtarget.systemSupportsUnalignedAccess() &&
2836       (SD->getAlign().value() < (MemVT.getSizeInBits() / 8)) &&
2837       ((MemVT == MVT::i32) || (MemVT == MVT::i64)))
2838     return lowerUnalignedIntStore(SD, DAG, Subtarget.isLittle());
2839 
2840   return lowerFP_TO_SINT_STORE(SD, DAG, Subtarget.isSingleFloat());
2841 }
2842 
lowerEH_DWARF_CFA(SDValue Op,SelectionDAG & DAG) const2843 SDValue MipsTargetLowering::lowerEH_DWARF_CFA(SDValue Op,
2844                                               SelectionDAG &DAG) const {
2845 
2846   // Return a fixed StackObject with offset 0 which points to the old stack
2847   // pointer.
2848   MachineFrameInfo &MFI = DAG.getMachineFunction().getFrameInfo();
2849   EVT ValTy = Op->getValueType(0);
2850   int FI = MFI.CreateFixedObject(Op.getValueSizeInBits() / 8, 0, false);
2851   return DAG.getFrameIndex(FI, ValTy);
2852 }
2853 
lowerFP_TO_SINT(SDValue Op,SelectionDAG & DAG) const2854 SDValue MipsTargetLowering::lowerFP_TO_SINT(SDValue Op,
2855                                             SelectionDAG &DAG) const {
2856   if (Op.getValueSizeInBits() > 32 && Subtarget.isSingleFloat())
2857     return SDValue();
2858 
2859   EVT FPTy = EVT::getFloatingPointVT(Op.getValueSizeInBits());
2860   SDValue Trunc = DAG.getNode(MipsISD::TruncIntFP, SDLoc(Op), FPTy,
2861                               Op.getOperand(0));
2862   return DAG.getNode(ISD::BITCAST, SDLoc(Op), Op.getValueType(), Trunc);
2863 }
2864 
2865 //===----------------------------------------------------------------------===//
2866 //                      Calling Convention Implementation
2867 //===----------------------------------------------------------------------===//
2868 
2869 //===----------------------------------------------------------------------===//
2870 // TODO: Implement a generic logic using tblgen that can support this.
2871 // Mips O32 ABI rules:
2872 // ---
2873 // i32 - Passed in A0, A1, A2, A3 and stack
2874 // f32 - Only passed in f32 registers if no int reg has been used yet to hold
2875 //       an argument. Otherwise, passed in A1, A2, A3 and stack.
2876 // f64 - Only passed in two aliased f32 registers if no int reg has been used
2877 //       yet to hold an argument. Otherwise, use A2, A3 and stack. If A1 is
2878 //       not used, it must be shadowed. If only A3 is available, shadow it and
2879 //       go to stack.
2880 // vXiX - Received as scalarized i32s, passed in A0 - A3 and the stack.
2881 // vXf32 - Passed in either a pair of registers {A0, A1}, {A2, A3} or {A0 - A3}
2882 //         with the remainder spilled to the stack.
2883 // vXf64 - Passed in either {A0, A1, A2, A3} or {A2, A3} and in both cases
2884 //         spilling the remainder to the stack.
2885 //
2886 //  For vararg functions, all arguments are passed in A0, A1, A2, A3 and stack.
2887 //===----------------------------------------------------------------------===//
2888 
CC_MipsO32(unsigned ValNo,MVT ValVT,MVT LocVT,CCValAssign::LocInfo LocInfo,ISD::ArgFlagsTy ArgFlags,CCState & State,ArrayRef<MCPhysReg> F64Regs)2889 static bool CC_MipsO32(unsigned ValNo, MVT ValVT, MVT LocVT,
2890                        CCValAssign::LocInfo LocInfo, ISD::ArgFlagsTy ArgFlags,
2891                        CCState &State, ArrayRef<MCPhysReg> F64Regs) {
2892   const MipsSubtarget &Subtarget = static_cast<const MipsSubtarget &>(
2893       State.getMachineFunction().getSubtarget());
2894 
2895   static const MCPhysReg IntRegs[] = { Mips::A0, Mips::A1, Mips::A2, Mips::A3 };
2896 
2897   const MipsCCState * MipsState = static_cast<MipsCCState *>(&State);
2898 
2899   static const MCPhysReg F32Regs[] = { Mips::F12, Mips::F14 };
2900 
2901   static const MCPhysReg FloatVectorIntRegs[] = { Mips::A0, Mips::A2 };
2902 
2903   // Do not process byval args here.
2904   if (ArgFlags.isByVal())
2905     return true;
2906 
2907   // Promote i8 and i16
2908   if (ArgFlags.isInReg() && !Subtarget.isLittle()) {
2909     if (LocVT == MVT::i8 || LocVT == MVT::i16 || LocVT == MVT::i32) {
2910       LocVT = MVT::i32;
2911       if (ArgFlags.isSExt())
2912         LocInfo = CCValAssign::SExtUpper;
2913       else if (ArgFlags.isZExt())
2914         LocInfo = CCValAssign::ZExtUpper;
2915       else
2916         LocInfo = CCValAssign::AExtUpper;
2917     }
2918   }
2919 
2920   // Promote i8 and i16
2921   if (LocVT == MVT::i8 || LocVT == MVT::i16) {
2922     LocVT = MVT::i32;
2923     if (ArgFlags.isSExt())
2924       LocInfo = CCValAssign::SExt;
2925     else if (ArgFlags.isZExt())
2926       LocInfo = CCValAssign::ZExt;
2927     else
2928       LocInfo = CCValAssign::AExt;
2929   }
2930 
2931   unsigned Reg;
2932 
2933   // f32 and f64 are allocated in A0, A1, A2, A3 when either of the following
2934   // is true: function is vararg, argument is 3rd or higher, there is previous
2935   // argument which is not f32 or f64.
2936   bool AllocateFloatsInIntReg = State.isVarArg() || ValNo > 1 ||
2937                                 State.getFirstUnallocated(F32Regs) != ValNo;
2938   Align OrigAlign = ArgFlags.getNonZeroOrigAlign();
2939   bool isI64 = (ValVT == MVT::i32 && OrigAlign == Align(8));
2940   bool isVectorFloat = MipsState->WasOriginalArgVectorFloat(ValNo);
2941 
2942   // The MIPS vector ABI for floats passes them in a pair of registers
2943   if (ValVT == MVT::i32 && isVectorFloat) {
2944     // This is the start of an vector that was scalarized into an unknown number
2945     // of components. It doesn't matter how many there are. Allocate one of the
2946     // notional 8 byte aligned registers which map onto the argument stack, and
2947     // shadow the register lost to alignment requirements.
2948     if (ArgFlags.isSplit()) {
2949       Reg = State.AllocateReg(FloatVectorIntRegs);
2950       if (Reg == Mips::A2)
2951         State.AllocateReg(Mips::A1);
2952       else if (Reg == 0)
2953         State.AllocateReg(Mips::A3);
2954     } else {
2955       // If we're an intermediate component of the split, we can just attempt to
2956       // allocate a register directly.
2957       Reg = State.AllocateReg(IntRegs);
2958     }
2959   } else if (ValVT == MVT::i32 ||
2960              (ValVT == MVT::f32 && AllocateFloatsInIntReg)) {
2961     Reg = State.AllocateReg(IntRegs);
2962     // If this is the first part of an i64 arg,
2963     // the allocated register must be either A0 or A2.
2964     if (isI64 && (Reg == Mips::A1 || Reg == Mips::A3))
2965       Reg = State.AllocateReg(IntRegs);
2966     LocVT = MVT::i32;
2967   } else if (ValVT == MVT::f64 && AllocateFloatsInIntReg) {
2968     // Allocate int register and shadow next int register. If first
2969     // available register is Mips::A1 or Mips::A3, shadow it too.
2970     Reg = State.AllocateReg(IntRegs);
2971     if (Reg == Mips::A1 || Reg == Mips::A3)
2972       Reg = State.AllocateReg(IntRegs);
2973 
2974     if (Reg) {
2975       LocVT = MVT::i32;
2976 
2977       State.addLoc(
2978           CCValAssign::getCustomReg(ValNo, ValVT, Reg, LocVT, LocInfo));
2979       MCRegister HiReg = State.AllocateReg(IntRegs);
2980       assert(HiReg);
2981       State.addLoc(
2982           CCValAssign::getCustomReg(ValNo, ValVT, HiReg, LocVT, LocInfo));
2983       return false;
2984     }
2985   } else if (ValVT.isFloatingPoint() && !AllocateFloatsInIntReg) {
2986     // we are guaranteed to find an available float register
2987     if (ValVT == MVT::f32) {
2988       Reg = State.AllocateReg(F32Regs);
2989       // Shadow int register
2990       State.AllocateReg(IntRegs);
2991     } else {
2992       Reg = State.AllocateReg(F64Regs);
2993       // Shadow int registers
2994       unsigned Reg2 = State.AllocateReg(IntRegs);
2995       if (Reg2 == Mips::A1 || Reg2 == Mips::A3)
2996         State.AllocateReg(IntRegs);
2997       State.AllocateReg(IntRegs);
2998     }
2999   } else
3000     llvm_unreachable("Cannot handle this ValVT.");
3001 
3002   if (!Reg) {
3003     unsigned Offset = State.AllocateStack(ValVT.getStoreSize(), OrigAlign);
3004     State.addLoc(CCValAssign::getMem(ValNo, ValVT, Offset, LocVT, LocInfo));
3005   } else
3006     State.addLoc(CCValAssign::getReg(ValNo, ValVT, Reg, LocVT, LocInfo));
3007 
3008   return false;
3009 }
3010 
CC_MipsO32_FP32(unsigned ValNo,MVT ValVT,MVT LocVT,CCValAssign::LocInfo LocInfo,ISD::ArgFlagsTy ArgFlags,CCState & State)3011 static bool CC_MipsO32_FP32(unsigned ValNo, MVT ValVT,
3012                             MVT LocVT, CCValAssign::LocInfo LocInfo,
3013                             ISD::ArgFlagsTy ArgFlags, CCState &State) {
3014   static const MCPhysReg F64Regs[] = { Mips::D6, Mips::D7 };
3015 
3016   return CC_MipsO32(ValNo, ValVT, LocVT, LocInfo, ArgFlags, State, F64Regs);
3017 }
3018 
CC_MipsO32_FP64(unsigned ValNo,MVT ValVT,MVT LocVT,CCValAssign::LocInfo LocInfo,ISD::ArgFlagsTy ArgFlags,CCState & State)3019 static bool CC_MipsO32_FP64(unsigned ValNo, MVT ValVT,
3020                             MVT LocVT, CCValAssign::LocInfo LocInfo,
3021                             ISD::ArgFlagsTy ArgFlags, CCState &State) {
3022   static const MCPhysReg F64Regs[] = { Mips::D12_64, Mips::D14_64 };
3023 
3024   return CC_MipsO32(ValNo, ValVT, LocVT, LocInfo, ArgFlags, State, F64Regs);
3025 }
3026 
3027 static bool CC_MipsO32(unsigned ValNo, MVT ValVT, MVT LocVT,
3028                        CCValAssign::LocInfo LocInfo, ISD::ArgFlagsTy ArgFlags,
3029                        CCState &State) LLVM_ATTRIBUTE_UNUSED;
3030 
3031 #include "MipsGenCallingConv.inc"
3032 
CCAssignFnForCall() const3033  CCAssignFn *MipsTargetLowering::CCAssignFnForCall() const{
3034    return CC_Mips_FixedArg;
3035  }
3036 
CCAssignFnForReturn() const3037  CCAssignFn *MipsTargetLowering::CCAssignFnForReturn() const{
3038    return RetCC_Mips;
3039  }
3040 //===----------------------------------------------------------------------===//
3041 //                  Call Calling Convention Implementation
3042 //===----------------------------------------------------------------------===//
3043 
passArgOnStack(SDValue StackPtr,unsigned Offset,SDValue Chain,SDValue Arg,const SDLoc & DL,bool IsTailCall,SelectionDAG & DAG) const3044 SDValue MipsTargetLowering::passArgOnStack(SDValue StackPtr, unsigned Offset,
3045                                            SDValue Chain, SDValue Arg,
3046                                            const SDLoc &DL, bool IsTailCall,
3047                                            SelectionDAG &DAG) const {
3048   if (!IsTailCall) {
3049     SDValue PtrOff =
3050         DAG.getNode(ISD::ADD, DL, getPointerTy(DAG.getDataLayout()), StackPtr,
3051                     DAG.getIntPtrConstant(Offset, DL));
3052     return DAG.getStore(Chain, DL, Arg, PtrOff, MachinePointerInfo());
3053   }
3054 
3055   MachineFrameInfo &MFI = DAG.getMachineFunction().getFrameInfo();
3056   int FI = MFI.CreateFixedObject(Arg.getValueSizeInBits() / 8, Offset, false);
3057   SDValue FIN = DAG.getFrameIndex(FI, getPointerTy(DAG.getDataLayout()));
3058   return DAG.getStore(Chain, DL, Arg, FIN, MachinePointerInfo(), MaybeAlign(),
3059                       MachineMemOperand::MOVolatile);
3060 }
3061 
3062 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) const3063 getOpndList(SmallVectorImpl<SDValue> &Ops,
3064             std::deque<std::pair<unsigned, SDValue>> &RegsToPass,
3065             bool IsPICCall, bool GlobalOrExternal, bool InternalLinkage,
3066             bool IsCallReloc, CallLoweringInfo &CLI, SDValue Callee,
3067             SDValue Chain) const {
3068   // Insert node "GP copy globalreg" before call to function.
3069   //
3070   // R_MIPS_CALL* operators (emitted when non-internal functions are called
3071   // in PIC mode) allow symbols to be resolved via lazy binding.
3072   // The lazy binding stub requires GP to point to the GOT.
3073   // Note that we don't need GP to point to the GOT for indirect calls
3074   // (when R_MIPS_CALL* is not used for the call) because Mips linker generates
3075   // lazy binding stub for a function only when R_MIPS_CALL* are the only relocs
3076   // used for the function (that is, Mips linker doesn't generate lazy binding
3077   // stub for a function whose address is taken in the program).
3078   if (IsPICCall && !InternalLinkage && IsCallReloc) {
3079     unsigned GPReg = ABI.IsN64() ? Mips::GP_64 : Mips::GP;
3080     EVT Ty = ABI.IsN64() ? MVT::i64 : MVT::i32;
3081     RegsToPass.push_back(std::make_pair(GPReg, getGlobalReg(CLI.DAG, Ty)));
3082   }
3083 
3084   // Build a sequence of copy-to-reg nodes chained together with token
3085   // chain and flag operands which copy the outgoing args into registers.
3086   // The InGlue in necessary since all emitted instructions must be
3087   // stuck together.
3088   SDValue InGlue;
3089 
3090   for (auto &R : RegsToPass) {
3091     Chain = CLI.DAG.getCopyToReg(Chain, CLI.DL, R.first, R.second, InGlue);
3092     InGlue = Chain.getValue(1);
3093   }
3094 
3095   // Add argument registers to the end of the list so that they are
3096   // known live into the call.
3097   for (auto &R : RegsToPass)
3098     Ops.push_back(CLI.DAG.getRegister(R.first, R.second.getValueType()));
3099 
3100   // Add a register mask operand representing the call-preserved registers.
3101   const TargetRegisterInfo *TRI = Subtarget.getRegisterInfo();
3102   const uint32_t *Mask =
3103       TRI->getCallPreservedMask(CLI.DAG.getMachineFunction(), CLI.CallConv);
3104   assert(Mask && "Missing call preserved mask for calling convention");
3105   if (Subtarget.inMips16HardFloat()) {
3106     if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(CLI.Callee)) {
3107       StringRef Sym = G->getGlobal()->getName();
3108       Function *F = G->getGlobal()->getParent()->getFunction(Sym);
3109       if (F && F->hasFnAttribute("__Mips16RetHelper")) {
3110         Mask = MipsRegisterInfo::getMips16RetHelperMask();
3111       }
3112     }
3113   }
3114   Ops.push_back(CLI.DAG.getRegisterMask(Mask));
3115 
3116   if (InGlue.getNode())
3117     Ops.push_back(InGlue);
3118 }
3119 
AdjustInstrPostInstrSelection(MachineInstr & MI,SDNode * Node) const3120 void MipsTargetLowering::AdjustInstrPostInstrSelection(MachineInstr &MI,
3121                                                        SDNode *Node) const {
3122   switch (MI.getOpcode()) {
3123     default:
3124       return;
3125     case Mips::JALR:
3126     case Mips::JALRPseudo:
3127     case Mips::JALR64:
3128     case Mips::JALR64Pseudo:
3129     case Mips::JALR16_MM:
3130     case Mips::JALRC16_MMR6:
3131     case Mips::TAILCALLREG:
3132     case Mips::TAILCALLREG64:
3133     case Mips::TAILCALLR6REG:
3134     case Mips::TAILCALL64R6REG:
3135     case Mips::TAILCALLREG_MM:
3136     case Mips::TAILCALLREG_MMR6: {
3137       if (!EmitJalrReloc ||
3138           Subtarget.inMips16Mode() ||
3139           !isPositionIndependent() ||
3140           Node->getNumOperands() < 1 ||
3141           Node->getOperand(0).getNumOperands() < 2) {
3142         return;
3143       }
3144       // We are after the callee address, set by LowerCall().
3145       // If added to MI, asm printer will emit .reloc R_MIPS_JALR for the
3146       // symbol.
3147       const SDValue TargetAddr = Node->getOperand(0).getOperand(1);
3148       StringRef Sym;
3149       if (const GlobalAddressSDNode *G =
3150               dyn_cast_or_null<const GlobalAddressSDNode>(TargetAddr)) {
3151         // We must not emit the R_MIPS_JALR relocation against data symbols
3152         // since this will cause run-time crashes if the linker replaces the
3153         // call instruction with a relative branch to the data symbol.
3154         if (!isa<Function>(G->getGlobal())) {
3155           LLVM_DEBUG(dbgs() << "Not adding R_MIPS_JALR against data symbol "
3156                             << G->getGlobal()->getName() << "\n");
3157           return;
3158         }
3159         Sym = G->getGlobal()->getName();
3160       }
3161       else if (const ExternalSymbolSDNode *ES =
3162                    dyn_cast_or_null<const ExternalSymbolSDNode>(TargetAddr)) {
3163         Sym = ES->getSymbol();
3164       }
3165 
3166       if (Sym.empty())
3167         return;
3168 
3169       MachineFunction *MF = MI.getParent()->getParent();
3170       MCSymbol *S = MF->getContext().getOrCreateSymbol(Sym);
3171       LLVM_DEBUG(dbgs() << "Adding R_MIPS_JALR against " << Sym << "\n");
3172       MI.addOperand(MachineOperand::CreateMCSymbol(S, MipsII::MO_JALR));
3173     }
3174   }
3175 }
3176 
3177 /// LowerCall - functions arguments are copied from virtual regs to
3178 /// (physical regs)/(stack frame), CALLSEQ_START and CALLSEQ_END are emitted.
3179 SDValue
LowerCall(TargetLowering::CallLoweringInfo & CLI,SmallVectorImpl<SDValue> & InVals) const3180 MipsTargetLowering::LowerCall(TargetLowering::CallLoweringInfo &CLI,
3181                               SmallVectorImpl<SDValue> &InVals) const {
3182   SelectionDAG &DAG                     = CLI.DAG;
3183   SDLoc DL                              = CLI.DL;
3184   SmallVectorImpl<ISD::OutputArg> &Outs = CLI.Outs;
3185   SmallVectorImpl<SDValue> &OutVals     = CLI.OutVals;
3186   SmallVectorImpl<ISD::InputArg> &Ins   = CLI.Ins;
3187   SDValue Chain                         = CLI.Chain;
3188   SDValue Callee                        = CLI.Callee;
3189   bool &IsTailCall                      = CLI.IsTailCall;
3190   CallingConv::ID CallConv              = CLI.CallConv;
3191   bool IsVarArg                         = CLI.IsVarArg;
3192 
3193   MachineFunction &MF = DAG.getMachineFunction();
3194   MachineFrameInfo &MFI = MF.getFrameInfo();
3195   const TargetFrameLowering *TFL = Subtarget.getFrameLowering();
3196   MipsFunctionInfo *FuncInfo = MF.getInfo<MipsFunctionInfo>();
3197   bool IsPIC = isPositionIndependent();
3198 
3199   // Analyze operands of the call, assigning locations to each operand.
3200   SmallVector<CCValAssign, 16> ArgLocs;
3201   MipsCCState CCInfo(
3202       CallConv, IsVarArg, DAG.getMachineFunction(), ArgLocs, *DAG.getContext(),
3203       MipsCCState::getSpecialCallingConvForCallee(Callee.getNode(), Subtarget));
3204 
3205   const ExternalSymbolSDNode *ES =
3206       dyn_cast_or_null<const ExternalSymbolSDNode>(Callee.getNode());
3207 
3208   // There is one case where CALLSEQ_START..CALLSEQ_END can be nested, which
3209   // is during the lowering of a call with a byval argument which produces
3210   // a call to memcpy. For the O32 case, this causes the caller to allocate
3211   // stack space for the reserved argument area for the callee, then recursively
3212   // again for the memcpy call. In the NEWABI case, this doesn't occur as those
3213   // ABIs mandate that the callee allocates the reserved argument area. We do
3214   // still produce nested CALLSEQ_START..CALLSEQ_END with zero space though.
3215   //
3216   // If the callee has a byval argument and memcpy is used, we are mandated
3217   // to already have produced a reserved argument area for the callee for O32.
3218   // Therefore, the reserved argument area can be reused for both calls.
3219   //
3220   // Other cases of calling memcpy cannot have a chain with a CALLSEQ_START
3221   // present, as we have yet to hook that node onto the chain.
3222   //
3223   // Hence, the CALLSEQ_START and CALLSEQ_END nodes can be eliminated in this
3224   // case. GCC does a similar trick, in that wherever possible, it calculates
3225   // the maximum out going argument area (including the reserved area), and
3226   // preallocates the stack space on entrance to the caller.
3227   //
3228   // FIXME: We should do the same for efficiency and space.
3229 
3230   // Note: The check on the calling convention below must match
3231   //       MipsABIInfo::GetCalleeAllocdArgSizeInBytes().
3232   bool MemcpyInByVal = ES && StringRef(ES->getSymbol()) == "memcpy" &&
3233                        CallConv != CallingConv::Fast &&
3234                        Chain.getOpcode() == ISD::CALLSEQ_START;
3235 
3236   // Allocate the reserved argument area. It seems strange to do this from the
3237   // caller side but removing it breaks the frame size calculation.
3238   unsigned ReservedArgArea =
3239       MemcpyInByVal ? 0 : ABI.GetCalleeAllocdArgSizeInBytes(CallConv);
3240   CCInfo.AllocateStack(ReservedArgArea, Align(1));
3241 
3242   CCInfo.AnalyzeCallOperands(Outs, CC_Mips, CLI.getArgs(),
3243                              ES ? ES->getSymbol() : nullptr);
3244 
3245   // Get a count of how many bytes are to be pushed on the stack.
3246   unsigned StackSize = CCInfo.getStackSize();
3247 
3248   // Call site info for function parameters tracking.
3249   MachineFunction::CallSiteInfo CSInfo;
3250 
3251   // Check if it's really possible to do a tail call. Restrict it to functions
3252   // that are part of this compilation unit.
3253   bool InternalLinkage = false;
3254   if (IsTailCall) {
3255     IsTailCall = isEligibleForTailCallOptimization(
3256         CCInfo, StackSize, *MF.getInfo<MipsFunctionInfo>());
3257     if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee)) {
3258       InternalLinkage = G->getGlobal()->hasInternalLinkage();
3259       IsTailCall &= (InternalLinkage || G->getGlobal()->hasLocalLinkage() ||
3260                      G->getGlobal()->hasPrivateLinkage() ||
3261                      G->getGlobal()->hasHiddenVisibility() ||
3262                      G->getGlobal()->hasProtectedVisibility());
3263      }
3264   }
3265   if (!IsTailCall && CLI.CB && CLI.CB->isMustTailCall())
3266     report_fatal_error("failed to perform tail call elimination on a call "
3267                        "site marked musttail");
3268 
3269   if (IsTailCall)
3270     ++NumTailCalls;
3271 
3272   // Chain is the output chain of the last Load/Store or CopyToReg node.
3273   // ByValChain is the output chain of the last Memcpy node created for copying
3274   // byval arguments to the stack.
3275   unsigned StackAlignment = TFL->getStackAlignment();
3276   StackSize = alignTo(StackSize, StackAlignment);
3277 
3278   if (!(IsTailCall || MemcpyInByVal))
3279     Chain = DAG.getCALLSEQ_START(Chain, StackSize, 0, DL);
3280 
3281   SDValue StackPtr =
3282       DAG.getCopyFromReg(Chain, DL, ABI.IsN64() ? Mips::SP_64 : Mips::SP,
3283                          getPointerTy(DAG.getDataLayout()));
3284 
3285   std::deque<std::pair<unsigned, SDValue>> RegsToPass;
3286   SmallVector<SDValue, 8> MemOpChains;
3287 
3288   CCInfo.rewindByValRegsInfo();
3289 
3290   // Walk the register/memloc assignments, inserting copies/loads.
3291   for (unsigned i = 0, e = ArgLocs.size(), OutIdx = 0; i != e; ++i, ++OutIdx) {
3292     SDValue Arg = OutVals[OutIdx];
3293     CCValAssign &VA = ArgLocs[i];
3294     MVT ValVT = VA.getValVT(), LocVT = VA.getLocVT();
3295     ISD::ArgFlagsTy Flags = Outs[OutIdx].Flags;
3296     bool UseUpperBits = false;
3297 
3298     // ByVal Arg.
3299     if (Flags.isByVal()) {
3300       unsigned FirstByValReg, LastByValReg;
3301       unsigned ByValIdx = CCInfo.getInRegsParamsProcessed();
3302       CCInfo.getInRegsParamInfo(ByValIdx, FirstByValReg, LastByValReg);
3303 
3304       assert(Flags.getByValSize() &&
3305              "ByVal args of size 0 should have been ignored by front-end.");
3306       assert(ByValIdx < CCInfo.getInRegsParamsCount());
3307       assert(!IsTailCall &&
3308              "Do not tail-call optimize if there is a byval argument.");
3309       passByValArg(Chain, DL, RegsToPass, MemOpChains, StackPtr, MFI, DAG, Arg,
3310                    FirstByValReg, LastByValReg, Flags, Subtarget.isLittle(),
3311                    VA);
3312       CCInfo.nextInRegsParam();
3313       continue;
3314     }
3315 
3316     // Promote the value if needed.
3317     switch (VA.getLocInfo()) {
3318     default:
3319       llvm_unreachable("Unknown loc info!");
3320     case CCValAssign::Full:
3321       if (VA.isRegLoc()) {
3322         if ((ValVT == MVT::f32 && LocVT == MVT::i32) ||
3323             (ValVT == MVT::f64 && LocVT == MVT::i64) ||
3324             (ValVT == MVT::i64 && LocVT == MVT::f64))
3325           Arg = DAG.getNode(ISD::BITCAST, DL, LocVT, Arg);
3326         else if (ValVT == MVT::f64 && LocVT == MVT::i32) {
3327           SDValue Lo = DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32,
3328                                    Arg, DAG.getConstant(0, DL, MVT::i32));
3329           SDValue Hi = DAG.getNode(MipsISD::ExtractElementF64, DL, MVT::i32,
3330                                    Arg, DAG.getConstant(1, DL, MVT::i32));
3331           if (!Subtarget.isLittle())
3332             std::swap(Lo, Hi);
3333 
3334           assert(VA.needsCustom());
3335 
3336           Register LocRegLo = VA.getLocReg();
3337           Register LocRegHigh = ArgLocs[++i].getLocReg();
3338           RegsToPass.push_back(std::make_pair(LocRegLo, Lo));
3339           RegsToPass.push_back(std::make_pair(LocRegHigh, Hi));
3340           continue;
3341         }
3342       }
3343       break;
3344     case CCValAssign::BCvt:
3345       Arg = DAG.getNode(ISD::BITCAST, DL, LocVT, Arg);
3346       break;
3347     case CCValAssign::SExtUpper:
3348       UseUpperBits = true;
3349       [[fallthrough]];
3350     case CCValAssign::SExt:
3351       Arg = DAG.getNode(ISD::SIGN_EXTEND, DL, LocVT, Arg);
3352       break;
3353     case CCValAssign::ZExtUpper:
3354       UseUpperBits = true;
3355       [[fallthrough]];
3356     case CCValAssign::ZExt:
3357       Arg = DAG.getNode(ISD::ZERO_EXTEND, DL, LocVT, Arg);
3358       break;
3359     case CCValAssign::AExtUpper:
3360       UseUpperBits = true;
3361       [[fallthrough]];
3362     case CCValAssign::AExt:
3363       Arg = DAG.getNode(ISD::ANY_EXTEND, DL, LocVT, Arg);
3364       break;
3365     }
3366 
3367     if (UseUpperBits) {
3368       unsigned ValSizeInBits = Outs[OutIdx].ArgVT.getSizeInBits();
3369       unsigned LocSizeInBits = VA.getLocVT().getSizeInBits();
3370       Arg = DAG.getNode(
3371           ISD::SHL, DL, VA.getLocVT(), Arg,
3372           DAG.getConstant(LocSizeInBits - ValSizeInBits, DL, VA.getLocVT()));
3373     }
3374 
3375     // Arguments that can be passed on register must be kept at
3376     // RegsToPass vector
3377     if (VA.isRegLoc()) {
3378       RegsToPass.push_back(std::make_pair(VA.getLocReg(), Arg));
3379 
3380       // If the parameter is passed through reg $D, which splits into
3381       // two physical registers, avoid creating call site info.
3382       if (Mips::AFGR64RegClass.contains(VA.getLocReg()))
3383         continue;
3384 
3385       // Collect CSInfo about which register passes which parameter.
3386       const TargetOptions &Options = DAG.getTarget().Options;
3387       if (Options.EmitCallSiteInfo)
3388         CSInfo.ArgRegPairs.emplace_back(VA.getLocReg(), i);
3389 
3390       continue;
3391     }
3392 
3393     // Register can't get to this point...
3394     assert(VA.isMemLoc());
3395 
3396     // emit ISD::STORE whichs stores the
3397     // parameter value to a stack Location
3398     MemOpChains.push_back(passArgOnStack(StackPtr, VA.getLocMemOffset(),
3399                                          Chain, Arg, DL, IsTailCall, DAG));
3400   }
3401 
3402   // Transform all store nodes into one single node because all store
3403   // nodes are independent of each other.
3404   if (!MemOpChains.empty())
3405     Chain = DAG.getNode(ISD::TokenFactor, DL, MVT::Other, MemOpChains);
3406 
3407   // If the callee is a GlobalAddress/ExternalSymbol node (quite common, every
3408   // direct call is) turn it into a TargetGlobalAddress/TargetExternalSymbol
3409   // node so that legalize doesn't hack it.
3410 
3411   EVT Ty = Callee.getValueType();
3412   bool GlobalOrExternal = false, IsCallReloc = false;
3413 
3414   // The long-calls feature is ignored in case of PIC.
3415   // While we do not support -mshared / -mno-shared properly,
3416   // ignore long-calls in case of -mabicalls too.
3417   if (!Subtarget.isABICalls() && !IsPIC) {
3418     // If the function should be called using "long call",
3419     // get its address into a register to prevent using
3420     // of the `jal` instruction for the direct call.
3421     if (auto *N = dyn_cast<ExternalSymbolSDNode>(Callee)) {
3422       if (Subtarget.useLongCalls())
3423         Callee = Subtarget.hasSym32()
3424                      ? getAddrNonPIC(N, SDLoc(N), Ty, DAG)
3425                      : getAddrNonPICSym64(N, SDLoc(N), Ty, DAG);
3426     } else if (auto *N = dyn_cast<GlobalAddressSDNode>(Callee)) {
3427       bool UseLongCalls = Subtarget.useLongCalls();
3428       // If the function has long-call/far/near attribute
3429       // it overrides command line switch pased to the backend.
3430       if (auto *F = dyn_cast<Function>(N->getGlobal())) {
3431         if (F->hasFnAttribute("long-call"))
3432           UseLongCalls = true;
3433         else if (F->hasFnAttribute("short-call"))
3434           UseLongCalls = false;
3435       }
3436       if (UseLongCalls)
3437         Callee = Subtarget.hasSym32()
3438                      ? getAddrNonPIC(N, SDLoc(N), Ty, DAG)
3439                      : getAddrNonPICSym64(N, SDLoc(N), Ty, DAG);
3440     }
3441   }
3442 
3443   if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee)) {
3444     if (IsPIC) {
3445       const GlobalValue *Val = G->getGlobal();
3446       InternalLinkage = Val->hasInternalLinkage();
3447 
3448       if (InternalLinkage)
3449         Callee = getAddrLocal(G, DL, Ty, DAG, ABI.IsN32() || ABI.IsN64());
3450       else if (Subtarget.useXGOT()) {
3451         Callee = getAddrGlobalLargeGOT(G, DL, Ty, DAG, MipsII::MO_CALL_HI16,
3452                                        MipsII::MO_CALL_LO16, Chain,
3453                                        FuncInfo->callPtrInfo(MF, Val));
3454         IsCallReloc = true;
3455       } else {
3456         Callee = getAddrGlobal(G, DL, Ty, DAG, MipsII::MO_GOT_CALL, Chain,
3457                                FuncInfo->callPtrInfo(MF, Val));
3458         IsCallReloc = true;
3459       }
3460     } else
3461       Callee = DAG.getTargetGlobalAddress(G->getGlobal(), DL,
3462                                           getPointerTy(DAG.getDataLayout()), 0,
3463                                           MipsII::MO_NO_FLAG);
3464     GlobalOrExternal = true;
3465   }
3466   else if (ExternalSymbolSDNode *S = dyn_cast<ExternalSymbolSDNode>(Callee)) {
3467     const char *Sym = S->getSymbol();
3468 
3469     if (!IsPIC) // static
3470       Callee = DAG.getTargetExternalSymbol(
3471           Sym, getPointerTy(DAG.getDataLayout()), MipsII::MO_NO_FLAG);
3472     else if (Subtarget.useXGOT()) {
3473       Callee = getAddrGlobalLargeGOT(S, DL, Ty, DAG, MipsII::MO_CALL_HI16,
3474                                      MipsII::MO_CALL_LO16, Chain,
3475                                      FuncInfo->callPtrInfo(MF, Sym));
3476       IsCallReloc = true;
3477     } else { // PIC
3478       Callee = getAddrGlobal(S, DL, Ty, DAG, MipsII::MO_GOT_CALL, Chain,
3479                              FuncInfo->callPtrInfo(MF, Sym));
3480       IsCallReloc = true;
3481     }
3482 
3483     GlobalOrExternal = true;
3484   }
3485 
3486   SmallVector<SDValue, 8> Ops(1, Chain);
3487   SDVTList NodeTys = DAG.getVTList(MVT::Other, MVT::Glue);
3488 
3489   getOpndList(Ops, RegsToPass, IsPIC, GlobalOrExternal, InternalLinkage,
3490               IsCallReloc, CLI, Callee, Chain);
3491 
3492   if (IsTailCall) {
3493     MF.getFrameInfo().setHasTailCall();
3494     SDValue Ret = DAG.getNode(MipsISD::TailCall, DL, MVT::Other, Ops);
3495     DAG.addCallSiteInfo(Ret.getNode(), std::move(CSInfo));
3496     return Ret;
3497   }
3498 
3499   Chain = DAG.getNode(MipsISD::JmpLink, DL, NodeTys, Ops);
3500   SDValue InGlue = Chain.getValue(1);
3501 
3502   DAG.addCallSiteInfo(Chain.getNode(), std::move(CSInfo));
3503 
3504   // Create the CALLSEQ_END node in the case of where it is not a call to
3505   // memcpy.
3506   if (!(MemcpyInByVal)) {
3507     Chain = DAG.getCALLSEQ_END(Chain, StackSize, 0, InGlue, DL);
3508     InGlue = Chain.getValue(1);
3509   }
3510 
3511   // Handle result values, copying them out of physregs into vregs that we
3512   // return.
3513   return LowerCallResult(Chain, InGlue, CallConv, IsVarArg, Ins, DL, DAG,
3514                          InVals, CLI);
3515 }
3516 
3517 /// LowerCallResult - Lower the result values of a call into the
3518 /// 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) const3519 SDValue MipsTargetLowering::LowerCallResult(
3520     SDValue Chain, SDValue InGlue, CallingConv::ID CallConv, bool IsVarArg,
3521     const SmallVectorImpl<ISD::InputArg> &Ins, const SDLoc &DL,
3522     SelectionDAG &DAG, SmallVectorImpl<SDValue> &InVals,
3523     TargetLowering::CallLoweringInfo &CLI) const {
3524   // Assign locations to each value returned by this call.
3525   SmallVector<CCValAssign, 16> RVLocs;
3526   MipsCCState CCInfo(CallConv, IsVarArg, DAG.getMachineFunction(), RVLocs,
3527                      *DAG.getContext());
3528 
3529   const ExternalSymbolSDNode *ES =
3530       dyn_cast_or_null<const ExternalSymbolSDNode>(CLI.Callee.getNode());
3531   CCInfo.AnalyzeCallResult(Ins, RetCC_Mips, CLI.RetTy,
3532                            ES ? ES->getSymbol() : nullptr);
3533 
3534   // Copy all of the result registers out of their specified physreg.
3535   for (unsigned i = 0; i != RVLocs.size(); ++i) {
3536     CCValAssign &VA = RVLocs[i];
3537     assert(VA.isRegLoc() && "Can only return in registers!");
3538 
3539     SDValue Val = DAG.getCopyFromReg(Chain, DL, RVLocs[i].getLocReg(),
3540                                      RVLocs[i].getLocVT(), InGlue);
3541     Chain = Val.getValue(1);
3542     InGlue = Val.getValue(2);
3543 
3544     if (VA.isUpperBitsInLoc()) {
3545       unsigned ValSizeInBits = Ins[i].ArgVT.getSizeInBits();
3546       unsigned LocSizeInBits = VA.getLocVT().getSizeInBits();
3547       unsigned Shift =
3548           VA.getLocInfo() == CCValAssign::ZExtUpper ? ISD::SRL : ISD::SRA;
3549       Val = DAG.getNode(
3550           Shift, DL, VA.getLocVT(), Val,
3551           DAG.getConstant(LocSizeInBits - ValSizeInBits, DL, VA.getLocVT()));
3552     }
3553 
3554     switch (VA.getLocInfo()) {
3555     default:
3556       llvm_unreachable("Unknown loc info!");
3557     case CCValAssign::Full:
3558       break;
3559     case CCValAssign::BCvt:
3560       Val = DAG.getNode(ISD::BITCAST, DL, VA.getValVT(), Val);
3561       break;
3562     case CCValAssign::AExt:
3563     case CCValAssign::AExtUpper:
3564       Val = DAG.getNode(ISD::TRUNCATE, DL, VA.getValVT(), Val);
3565       break;
3566     case CCValAssign::ZExt:
3567     case CCValAssign::ZExtUpper:
3568       Val = DAG.getNode(ISD::AssertZext, DL, VA.getLocVT(), Val,
3569                         DAG.getValueType(VA.getValVT()));
3570       Val = DAG.getNode(ISD::TRUNCATE, DL, VA.getValVT(), Val);
3571       break;
3572     case CCValAssign::SExt:
3573     case CCValAssign::SExtUpper:
3574       Val = DAG.getNode(ISD::AssertSext, DL, VA.getLocVT(), Val,
3575                         DAG.getValueType(VA.getValVT()));
3576       Val = DAG.getNode(ISD::TRUNCATE, DL, VA.getValVT(), Val);
3577       break;
3578     }
3579 
3580     InVals.push_back(Val);
3581   }
3582 
3583   return Chain;
3584 }
3585 
UnpackFromArgumentSlot(SDValue Val,const CCValAssign & VA,EVT ArgVT,const SDLoc & DL,SelectionDAG & DAG)3586 static SDValue UnpackFromArgumentSlot(SDValue Val, const CCValAssign &VA,
3587                                       EVT ArgVT, const SDLoc &DL,
3588                                       SelectionDAG &DAG) {
3589   MVT LocVT = VA.getLocVT();
3590   EVT ValVT = VA.getValVT();
3591 
3592   // Shift into the upper bits if necessary.
3593   switch (VA.getLocInfo()) {
3594   default:
3595     break;
3596   case CCValAssign::AExtUpper:
3597   case CCValAssign::SExtUpper:
3598   case CCValAssign::ZExtUpper: {
3599     unsigned ValSizeInBits = ArgVT.getSizeInBits();
3600     unsigned LocSizeInBits = VA.getLocVT().getSizeInBits();
3601     unsigned Opcode =
3602         VA.getLocInfo() == CCValAssign::ZExtUpper ? ISD::SRL : ISD::SRA;
3603     Val = DAG.getNode(
3604         Opcode, DL, VA.getLocVT(), Val,
3605         DAG.getConstant(LocSizeInBits - ValSizeInBits, DL, VA.getLocVT()));
3606     break;
3607   }
3608   }
3609 
3610   // If this is an value smaller than the argument slot size (32-bit for O32,
3611   // 64-bit for N32/N64), it has been promoted in some way to the argument slot
3612   // size. Extract the value and insert any appropriate assertions regarding
3613   // sign/zero extension.
3614   switch (VA.getLocInfo()) {
3615   default:
3616     llvm_unreachable("Unknown loc info!");
3617   case CCValAssign::Full:
3618     break;
3619   case CCValAssign::AExtUpper:
3620   case CCValAssign::AExt:
3621     Val = DAG.getNode(ISD::TRUNCATE, DL, ValVT, Val);
3622     break;
3623   case CCValAssign::SExtUpper:
3624   case CCValAssign::SExt:
3625     Val = DAG.getNode(ISD::AssertSext, DL, LocVT, Val, DAG.getValueType(ValVT));
3626     Val = DAG.getNode(ISD::TRUNCATE, DL, ValVT, Val);
3627     break;
3628   case CCValAssign::ZExtUpper:
3629   case CCValAssign::ZExt:
3630     Val = DAG.getNode(ISD::AssertZext, DL, LocVT, Val, DAG.getValueType(ValVT));
3631     Val = DAG.getNode(ISD::TRUNCATE, DL, ValVT, Val);
3632     break;
3633   case CCValAssign::BCvt:
3634     Val = DAG.getNode(ISD::BITCAST, DL, ValVT, Val);
3635     break;
3636   }
3637 
3638   return Val;
3639 }
3640 
3641 //===----------------------------------------------------------------------===//
3642 //             Formal Arguments Calling Convention Implementation
3643 //===----------------------------------------------------------------------===//
3644 /// LowerFormalArguments - transform physical registers into virtual registers
3645 /// 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) const3646 SDValue MipsTargetLowering::LowerFormalArguments(
3647     SDValue Chain, CallingConv::ID CallConv, bool IsVarArg,
3648     const SmallVectorImpl<ISD::InputArg> &Ins, const SDLoc &DL,
3649     SelectionDAG &DAG, SmallVectorImpl<SDValue> &InVals) const {
3650   MachineFunction &MF = DAG.getMachineFunction();
3651   MachineFrameInfo &MFI = MF.getFrameInfo();
3652   MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
3653 
3654   MipsFI->setVarArgsFrameIndex(0);
3655 
3656   // Used with vargs to acumulate store chains.
3657   std::vector<SDValue> OutChains;
3658 
3659   // Assign locations to all of the incoming arguments.
3660   SmallVector<CCValAssign, 16> ArgLocs;
3661   MipsCCState CCInfo(CallConv, IsVarArg, DAG.getMachineFunction(), ArgLocs,
3662                      *DAG.getContext());
3663   CCInfo.AllocateStack(ABI.GetCalleeAllocdArgSizeInBytes(CallConv), Align(1));
3664   const Function &Func = DAG.getMachineFunction().getFunction();
3665   Function::const_arg_iterator FuncArg = Func.arg_begin();
3666 
3667   if (Func.hasFnAttribute("interrupt") && !Func.arg_empty())
3668     report_fatal_error(
3669         "Functions with the interrupt attribute cannot have arguments!");
3670 
3671   CCInfo.AnalyzeFormalArguments(Ins, CC_Mips_FixedArg);
3672   MipsFI->setFormalArgInfo(CCInfo.getStackSize(),
3673                            CCInfo.getInRegsParamsCount() > 0);
3674 
3675   unsigned CurArgIdx = 0;
3676   CCInfo.rewindByValRegsInfo();
3677 
3678   for (unsigned i = 0, e = ArgLocs.size(), InsIdx = 0; i != e; ++i, ++InsIdx) {
3679     CCValAssign &VA = ArgLocs[i];
3680     if (Ins[InsIdx].isOrigArg()) {
3681       std::advance(FuncArg, Ins[InsIdx].getOrigArgIndex() - CurArgIdx);
3682       CurArgIdx = Ins[InsIdx].getOrigArgIndex();
3683     }
3684     EVT ValVT = VA.getValVT();
3685     ISD::ArgFlagsTy Flags = Ins[InsIdx].Flags;
3686     bool IsRegLoc = VA.isRegLoc();
3687 
3688     if (Flags.isByVal()) {
3689       assert(Ins[InsIdx].isOrigArg() && "Byval arguments cannot be implicit");
3690       unsigned FirstByValReg, LastByValReg;
3691       unsigned ByValIdx = CCInfo.getInRegsParamsProcessed();
3692       CCInfo.getInRegsParamInfo(ByValIdx, FirstByValReg, LastByValReg);
3693 
3694       assert(Flags.getByValSize() &&
3695              "ByVal args of size 0 should have been ignored by front-end.");
3696       assert(ByValIdx < CCInfo.getInRegsParamsCount());
3697       copyByValRegs(Chain, DL, OutChains, DAG, Flags, InVals, &*FuncArg,
3698                     FirstByValReg, LastByValReg, VA, CCInfo);
3699       CCInfo.nextInRegsParam();
3700       continue;
3701     }
3702 
3703     // Arguments stored on registers
3704     if (IsRegLoc) {
3705       MVT RegVT = VA.getLocVT();
3706       Register ArgReg = VA.getLocReg();
3707       const TargetRegisterClass *RC = getRegClassFor(RegVT);
3708 
3709       // Transform the arguments stored on
3710       // physical registers into virtual ones
3711       unsigned Reg = addLiveIn(DAG.getMachineFunction(), ArgReg, RC);
3712       SDValue ArgValue = DAG.getCopyFromReg(Chain, DL, Reg, RegVT);
3713 
3714       ArgValue =
3715           UnpackFromArgumentSlot(ArgValue, VA, Ins[InsIdx].ArgVT, DL, DAG);
3716 
3717       // Handle floating point arguments passed in integer registers and
3718       // long double arguments passed in floating point registers.
3719       if ((RegVT == MVT::i32 && ValVT == MVT::f32) ||
3720           (RegVT == MVT::i64 && ValVT == MVT::f64) ||
3721           (RegVT == MVT::f64 && ValVT == MVT::i64))
3722         ArgValue = DAG.getNode(ISD::BITCAST, DL, ValVT, ArgValue);
3723       else if (ABI.IsO32() && RegVT == MVT::i32 &&
3724                ValVT == MVT::f64) {
3725         assert(VA.needsCustom() && "Expected custom argument for f64 split");
3726         CCValAssign &NextVA = ArgLocs[++i];
3727         unsigned Reg2 =
3728             addLiveIn(DAG.getMachineFunction(), NextVA.getLocReg(), RC);
3729         SDValue ArgValue2 = DAG.getCopyFromReg(Chain, DL, Reg2, RegVT);
3730         if (!Subtarget.isLittle())
3731           std::swap(ArgValue, ArgValue2);
3732         ArgValue = DAG.getNode(MipsISD::BuildPairF64, DL, MVT::f64,
3733                                ArgValue, ArgValue2);
3734       }
3735 
3736       InVals.push_back(ArgValue);
3737     } else { // VA.isRegLoc()
3738       MVT LocVT = VA.getLocVT();
3739 
3740       assert(!VA.needsCustom() && "unexpected custom memory argument");
3741 
3742       // Only arguments pased on the stack should make it here.
3743       assert(VA.isMemLoc());
3744 
3745       // The stack pointer offset is relative to the caller stack frame.
3746       int FI = MFI.CreateFixedObject(LocVT.getSizeInBits() / 8,
3747                                      VA.getLocMemOffset(), true);
3748 
3749       // Create load nodes to retrieve arguments from the stack
3750       SDValue FIN = DAG.getFrameIndex(FI, getPointerTy(DAG.getDataLayout()));
3751       SDValue ArgValue = DAG.getLoad(
3752           LocVT, DL, Chain, FIN,
3753           MachinePointerInfo::getFixedStack(DAG.getMachineFunction(), FI));
3754       OutChains.push_back(ArgValue.getValue(1));
3755 
3756       ArgValue =
3757           UnpackFromArgumentSlot(ArgValue, VA, Ins[InsIdx].ArgVT, DL, DAG);
3758 
3759       InVals.push_back(ArgValue);
3760     }
3761   }
3762 
3763   for (unsigned i = 0, e = ArgLocs.size(), InsIdx = 0; i != e; ++i, ++InsIdx) {
3764 
3765     if (ArgLocs[i].needsCustom()) {
3766       ++i;
3767       continue;
3768     }
3769 
3770     // The mips ABIs for returning structs by value requires that we copy
3771     // the sret argument into $v0 for the return. Save the argument into
3772     // a virtual register so that we can access it from the return points.
3773     if (Ins[InsIdx].Flags.isSRet()) {
3774       unsigned Reg = MipsFI->getSRetReturnReg();
3775       if (!Reg) {
3776         Reg = MF.getRegInfo().createVirtualRegister(
3777             getRegClassFor(ABI.IsN64() ? MVT::i64 : MVT::i32));
3778         MipsFI->setSRetReturnReg(Reg);
3779       }
3780       SDValue Copy = DAG.getCopyToReg(DAG.getEntryNode(), DL, Reg, InVals[i]);
3781       Chain = DAG.getNode(ISD::TokenFactor, DL, MVT::Other, Copy, Chain);
3782       break;
3783     }
3784   }
3785 
3786   if (IsVarArg)
3787     writeVarArgRegs(OutChains, Chain, DL, DAG, CCInfo);
3788 
3789   // All stores are grouped in one node to allow the matching between
3790   // the size of Ins and InVals. This only happens when on varg functions
3791   if (!OutChains.empty()) {
3792     OutChains.push_back(Chain);
3793     Chain = DAG.getNode(ISD::TokenFactor, DL, MVT::Other, OutChains);
3794   }
3795 
3796   return Chain;
3797 }
3798 
3799 //===----------------------------------------------------------------------===//
3800 //               Return Value Calling Convention Implementation
3801 //===----------------------------------------------------------------------===//
3802 
3803 bool
CanLowerReturn(CallingConv::ID CallConv,MachineFunction & MF,bool IsVarArg,const SmallVectorImpl<ISD::OutputArg> & Outs,LLVMContext & Context) const3804 MipsTargetLowering::CanLowerReturn(CallingConv::ID CallConv,
3805                                    MachineFunction &MF, bool IsVarArg,
3806                                    const SmallVectorImpl<ISD::OutputArg> &Outs,
3807                                    LLVMContext &Context) const {
3808   SmallVector<CCValAssign, 16> RVLocs;
3809   MipsCCState CCInfo(CallConv, IsVarArg, MF, RVLocs, Context);
3810   return CCInfo.CheckReturn(Outs, RetCC_Mips);
3811 }
3812 
shouldSignExtendTypeInLibCall(EVT Type,bool IsSigned) const3813 bool MipsTargetLowering::shouldSignExtendTypeInLibCall(EVT Type,
3814                                                        bool IsSigned) const {
3815   if ((ABI.IsN32() || ABI.IsN64()) && Type == MVT::i32)
3816       return true;
3817 
3818   return IsSigned;
3819 }
3820 
3821 SDValue
LowerInterruptReturn(SmallVectorImpl<SDValue> & RetOps,const SDLoc & DL,SelectionDAG & DAG) const3822 MipsTargetLowering::LowerInterruptReturn(SmallVectorImpl<SDValue> &RetOps,
3823                                          const SDLoc &DL,
3824                                          SelectionDAG &DAG) const {
3825   MachineFunction &MF = DAG.getMachineFunction();
3826   MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
3827 
3828   MipsFI->setISR();
3829 
3830   return DAG.getNode(MipsISD::ERet, DL, MVT::Other, RetOps);
3831 }
3832 
3833 SDValue
LowerReturn(SDValue Chain,CallingConv::ID CallConv,bool IsVarArg,const SmallVectorImpl<ISD::OutputArg> & Outs,const SmallVectorImpl<SDValue> & OutVals,const SDLoc & DL,SelectionDAG & DAG) const3834 MipsTargetLowering::LowerReturn(SDValue Chain, CallingConv::ID CallConv,
3835                                 bool IsVarArg,
3836                                 const SmallVectorImpl<ISD::OutputArg> &Outs,
3837                                 const SmallVectorImpl<SDValue> &OutVals,
3838                                 const SDLoc &DL, SelectionDAG &DAG) const {
3839   // CCValAssign - represent the assignment of
3840   // the return value to a location
3841   SmallVector<CCValAssign, 16> RVLocs;
3842   MachineFunction &MF = DAG.getMachineFunction();
3843 
3844   // CCState - Info about the registers and stack slot.
3845   MipsCCState CCInfo(CallConv, IsVarArg, MF, RVLocs, *DAG.getContext());
3846 
3847   // Analyze return values.
3848   CCInfo.AnalyzeReturn(Outs, RetCC_Mips);
3849 
3850   SDValue Glue;
3851   SmallVector<SDValue, 4> RetOps(1, Chain);
3852 
3853   // Copy the result values into the output registers.
3854   for (unsigned i = 0; i != RVLocs.size(); ++i) {
3855     SDValue Val = OutVals[i];
3856     CCValAssign &VA = RVLocs[i];
3857     assert(VA.isRegLoc() && "Can only return in registers!");
3858     bool UseUpperBits = false;
3859 
3860     switch (VA.getLocInfo()) {
3861     default:
3862       llvm_unreachable("Unknown loc info!");
3863     case CCValAssign::Full:
3864       break;
3865     case CCValAssign::BCvt:
3866       Val = DAG.getNode(ISD::BITCAST, DL, VA.getLocVT(), Val);
3867       break;
3868     case CCValAssign::AExtUpper:
3869       UseUpperBits = true;
3870       [[fallthrough]];
3871     case CCValAssign::AExt:
3872       Val = DAG.getNode(ISD::ANY_EXTEND, DL, VA.getLocVT(), Val);
3873       break;
3874     case CCValAssign::ZExtUpper:
3875       UseUpperBits = true;
3876       [[fallthrough]];
3877     case CCValAssign::ZExt:
3878       Val = DAG.getNode(ISD::ZERO_EXTEND, DL, VA.getLocVT(), Val);
3879       break;
3880     case CCValAssign::SExtUpper:
3881       UseUpperBits = true;
3882       [[fallthrough]];
3883     case CCValAssign::SExt:
3884       Val = DAG.getNode(ISD::SIGN_EXTEND, DL, VA.getLocVT(), Val);
3885       break;
3886     }
3887 
3888     if (UseUpperBits) {
3889       unsigned ValSizeInBits = Outs[i].ArgVT.getSizeInBits();
3890       unsigned LocSizeInBits = VA.getLocVT().getSizeInBits();
3891       Val = DAG.getNode(
3892           ISD::SHL, DL, VA.getLocVT(), Val,
3893           DAG.getConstant(LocSizeInBits - ValSizeInBits, DL, VA.getLocVT()));
3894     }
3895 
3896     Chain = DAG.getCopyToReg(Chain, DL, VA.getLocReg(), Val, Glue);
3897 
3898     // Guarantee that all emitted copies are stuck together with flags.
3899     Glue = Chain.getValue(1);
3900     RetOps.push_back(DAG.getRegister(VA.getLocReg(), VA.getLocVT()));
3901   }
3902 
3903   // The mips ABIs for returning structs by value requires that we copy
3904   // the sret argument into $v0 for the return. We saved the argument into
3905   // a virtual register in the entry block, so now we copy the value out
3906   // and into $v0.
3907   if (MF.getFunction().hasStructRetAttr()) {
3908     MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
3909     unsigned Reg = MipsFI->getSRetReturnReg();
3910 
3911     if (!Reg)
3912       llvm_unreachable("sret virtual register not created in the entry block");
3913     SDValue Val =
3914         DAG.getCopyFromReg(Chain, DL, Reg, getPointerTy(DAG.getDataLayout()));
3915     unsigned V0 = ABI.IsN64() ? Mips::V0_64 : Mips::V0;
3916 
3917     Chain = DAG.getCopyToReg(Chain, DL, V0, Val, Glue);
3918     Glue = Chain.getValue(1);
3919     RetOps.push_back(DAG.getRegister(V0, getPointerTy(DAG.getDataLayout())));
3920   }
3921 
3922   RetOps[0] = Chain;  // Update chain.
3923 
3924   // Add the glue if we have it.
3925   if (Glue.getNode())
3926     RetOps.push_back(Glue);
3927 
3928   // ISRs must use "eret".
3929   if (DAG.getMachineFunction().getFunction().hasFnAttribute("interrupt"))
3930     return LowerInterruptReturn(RetOps, DL, DAG);
3931 
3932   // Standard return on Mips is a "jr $ra"
3933   return DAG.getNode(MipsISD::Ret, DL, MVT::Other, RetOps);
3934 }
3935 
3936 //===----------------------------------------------------------------------===//
3937 //                           Mips Inline Assembly Support
3938 //===----------------------------------------------------------------------===//
3939 
3940 /// getConstraintType - Given a constraint letter, return the type of
3941 /// constraint it is for this target.
3942 MipsTargetLowering::ConstraintType
getConstraintType(StringRef Constraint) const3943 MipsTargetLowering::getConstraintType(StringRef Constraint) const {
3944   // Mips specific constraints
3945   // GCC config/mips/constraints.md
3946   //
3947   // 'd' : An address register. Equivalent to r
3948   //       unless generating MIPS16 code.
3949   // 'y' : Equivalent to r; retained for
3950   //       backwards compatibility.
3951   // 'c' : A register suitable for use in an indirect
3952   //       jump. This will always be $25 for -mabicalls.
3953   // 'l' : The lo register. 1 word storage.
3954   // 'x' : The hilo register pair. Double word storage.
3955   if (Constraint.size() == 1) {
3956     switch (Constraint[0]) {
3957       default : break;
3958       case 'd':
3959       case 'y':
3960       case 'f':
3961       case 'c':
3962       case 'l':
3963       case 'x':
3964         return C_RegisterClass;
3965       case 'R':
3966         return C_Memory;
3967     }
3968   }
3969 
3970   if (Constraint == "ZC")
3971     return C_Memory;
3972 
3973   return TargetLowering::getConstraintType(Constraint);
3974 }
3975 
3976 /// Examine constraint type and operand type and determine a weight value.
3977 /// This object must already have been set up with the operand type
3978 /// and the current alternative constraint selected.
3979 TargetLowering::ConstraintWeight
getSingleConstraintMatchWeight(AsmOperandInfo & info,const char * constraint) const3980 MipsTargetLowering::getSingleConstraintMatchWeight(
3981     AsmOperandInfo &info, const char *constraint) const {
3982   ConstraintWeight weight = CW_Invalid;
3983   Value *CallOperandVal = info.CallOperandVal;
3984     // If we don't have a value, we can't do a match,
3985     // but allow it at the lowest weight.
3986   if (!CallOperandVal)
3987     return CW_Default;
3988   Type *type = CallOperandVal->getType();
3989   // Look at the constraint type.
3990   switch (*constraint) {
3991   default:
3992     weight = TargetLowering::getSingleConstraintMatchWeight(info, constraint);
3993     break;
3994   case 'd':
3995   case 'y':
3996     if (type->isIntegerTy())
3997       weight = CW_Register;
3998     break;
3999   case 'f': // FPU or MSA register
4000     if (Subtarget.hasMSA() && type->isVectorTy() &&
4001         type->getPrimitiveSizeInBits().getFixedValue() == 128)
4002       weight = CW_Register;
4003     else if (type->isFloatTy())
4004       weight = CW_Register;
4005     break;
4006   case 'c': // $25 for indirect jumps
4007   case 'l': // lo register
4008   case 'x': // hilo register pair
4009     if (type->isIntegerTy())
4010       weight = CW_SpecificReg;
4011     break;
4012   case 'I': // signed 16 bit immediate
4013   case 'J': // integer zero
4014   case 'K': // unsigned 16 bit immediate
4015   case 'L': // signed 32 bit immediate where lower 16 bits are 0
4016   case 'N': // immediate in the range of -65535 to -1 (inclusive)
4017   case 'O': // signed 15 bit immediate (+- 16383)
4018   case 'P': // immediate in the range of 65535 to 1 (inclusive)
4019     if (isa<ConstantInt>(CallOperandVal))
4020       weight = CW_Constant;
4021     break;
4022   case 'R':
4023     weight = CW_Memory;
4024     break;
4025   }
4026   return weight;
4027 }
4028 
4029 /// This is a helper function to parse a physical register string and split it
4030 /// into non-numeric and numeric parts (Prefix and Reg). The first boolean flag
4031 /// that is returned indicates whether parsing was successful. The second flag
4032 /// is true if the numeric part exists.
parsePhysicalReg(StringRef C,StringRef & Prefix,unsigned long long & Reg)4033 static std::pair<bool, bool> parsePhysicalReg(StringRef C, StringRef &Prefix,
4034                                               unsigned long long &Reg) {
4035   if (C.front() != '{' || C.back() != '}')
4036     return std::make_pair(false, false);
4037 
4038   // Search for the first numeric character.
4039   StringRef::const_iterator I, B = C.begin() + 1, E = C.end() - 1;
4040   I = std::find_if(B, E, isdigit);
4041 
4042   Prefix = StringRef(B, I - B);
4043 
4044   // The second flag is set to false if no numeric characters were found.
4045   if (I == E)
4046     return std::make_pair(true, false);
4047 
4048   // Parse the numeric characters.
4049   return std::make_pair(!getAsUnsignedInteger(StringRef(I, E - I), 10, Reg),
4050                         true);
4051 }
4052 
getTypeForExtReturn(LLVMContext & Context,EVT VT,ISD::NodeType) const4053 EVT MipsTargetLowering::getTypeForExtReturn(LLVMContext &Context, EVT VT,
4054                                             ISD::NodeType) const {
4055   bool Cond = !Subtarget.isABI_O32() && VT.getSizeInBits() == 32;
4056   EVT MinVT = getRegisterType(Cond ? MVT::i64 : MVT::i32);
4057   return VT.bitsLT(MinVT) ? MinVT : VT;
4058 }
4059 
4060 std::pair<unsigned, const TargetRegisterClass *> MipsTargetLowering::
parseRegForInlineAsmConstraint(StringRef C,MVT VT) const4061 parseRegForInlineAsmConstraint(StringRef C, MVT VT) const {
4062   const TargetRegisterInfo *TRI =
4063       Subtarget.getRegisterInfo();
4064   const TargetRegisterClass *RC;
4065   StringRef Prefix;
4066   unsigned long long Reg;
4067 
4068   std::pair<bool, bool> R = parsePhysicalReg(C, Prefix, Reg);
4069 
4070   if (!R.first)
4071     return std::make_pair(0U, nullptr);
4072 
4073   if ((Prefix == "hi" || Prefix == "lo")) { // Parse hi/lo.
4074     // No numeric characters follow "hi" or "lo".
4075     if (R.second)
4076       return std::make_pair(0U, nullptr);
4077 
4078     RC = TRI->getRegClass(Prefix == "hi" ?
4079                           Mips::HI32RegClassID : Mips::LO32RegClassID);
4080     return std::make_pair(*(RC->begin()), RC);
4081   } else if (Prefix.starts_with("$msa")) {
4082     // Parse $msa(ir|csr|access|save|modify|request|map|unmap)
4083 
4084     // No numeric characters follow the name.
4085     if (R.second)
4086       return std::make_pair(0U, nullptr);
4087 
4088     Reg = StringSwitch<unsigned long long>(Prefix)
4089               .Case("$msair", Mips::MSAIR)
4090               .Case("$msacsr", Mips::MSACSR)
4091               .Case("$msaaccess", Mips::MSAAccess)
4092               .Case("$msasave", Mips::MSASave)
4093               .Case("$msamodify", Mips::MSAModify)
4094               .Case("$msarequest", Mips::MSARequest)
4095               .Case("$msamap", Mips::MSAMap)
4096               .Case("$msaunmap", Mips::MSAUnmap)
4097               .Default(0);
4098 
4099     if (!Reg)
4100       return std::make_pair(0U, nullptr);
4101 
4102     RC = TRI->getRegClass(Mips::MSACtrlRegClassID);
4103     return std::make_pair(Reg, RC);
4104   }
4105 
4106   if (!R.second)
4107     return std::make_pair(0U, nullptr);
4108 
4109   if (Prefix == "$f") { // Parse $f0-$f31.
4110     // If the size of FP registers is 64-bit or Reg is an even number, select
4111     // the 64-bit register class. Otherwise, select the 32-bit register class.
4112     if (VT == MVT::Other)
4113       VT = (Subtarget.isFP64bit() || !(Reg % 2)) ? MVT::f64 : MVT::f32;
4114 
4115     RC = getRegClassFor(VT);
4116 
4117     if (RC == &Mips::AFGR64RegClass) {
4118       assert(Reg % 2 == 0);
4119       Reg >>= 1;
4120     }
4121   } else if (Prefix == "$fcc") // Parse $fcc0-$fcc7.
4122     RC = TRI->getRegClass(Mips::FCCRegClassID);
4123   else if (Prefix == "$w") { // Parse $w0-$w31.
4124     RC = getRegClassFor((VT == MVT::Other) ? MVT::v16i8 : VT);
4125   } else { // Parse $0-$31.
4126     assert(Prefix == "$");
4127     RC = getRegClassFor((VT == MVT::Other) ? MVT::i32 : VT);
4128   }
4129 
4130   assert(Reg < RC->getNumRegs());
4131   return std::make_pair(*(RC->begin() + Reg), RC);
4132 }
4133 
4134 /// Given a register class constraint, like 'r', if this corresponds directly
4135 /// to an LLVM register class, return a register of 0 and the register class
4136 /// pointer.
4137 std::pair<unsigned, const TargetRegisterClass *>
getRegForInlineAsmConstraint(const TargetRegisterInfo * TRI,StringRef Constraint,MVT VT) const4138 MipsTargetLowering::getRegForInlineAsmConstraint(const TargetRegisterInfo *TRI,
4139                                                  StringRef Constraint,
4140                                                  MVT VT) const {
4141   if (Constraint.size() == 1) {
4142     switch (Constraint[0]) {
4143     case 'd': // Address register. Same as 'r' unless generating MIPS16 code.
4144     case 'y': // Same as 'r'. Exists for compatibility.
4145     case 'r':
4146       if ((VT == MVT::i32 || VT == MVT::i16 || VT == MVT::i8 ||
4147            VT == MVT::i1) ||
4148           (VT == MVT::f32 && Subtarget.useSoftFloat())) {
4149         if (Subtarget.inMips16Mode())
4150           return std::make_pair(0U, &Mips::CPU16RegsRegClass);
4151         return std::make_pair(0U, &Mips::GPR32RegClass);
4152       }
4153       if ((VT == MVT::i64 || (VT == MVT::f64 && Subtarget.useSoftFloat())) &&
4154           !Subtarget.isGP64bit())
4155         return std::make_pair(0U, &Mips::GPR32RegClass);
4156       if ((VT == MVT::i64 || (VT == MVT::f64 && Subtarget.useSoftFloat())) &&
4157           Subtarget.isGP64bit())
4158         return std::make_pair(0U, &Mips::GPR64RegClass);
4159       // This will generate an error message
4160       return std::make_pair(0U, nullptr);
4161     case 'f': // FPU or MSA register
4162       if (VT == MVT::v16i8)
4163         return std::make_pair(0U, &Mips::MSA128BRegClass);
4164       else if (VT == MVT::v8i16 || VT == MVT::v8f16)
4165         return std::make_pair(0U, &Mips::MSA128HRegClass);
4166       else if (VT == MVT::v4i32 || VT == MVT::v4f32)
4167         return std::make_pair(0U, &Mips::MSA128WRegClass);
4168       else if (VT == MVT::v2i64 || VT == MVT::v2f64)
4169         return std::make_pair(0U, &Mips::MSA128DRegClass);
4170       else if (VT == MVT::f32)
4171         return std::make_pair(0U, &Mips::FGR32RegClass);
4172       else if ((VT == MVT::f64) && (!Subtarget.isSingleFloat())) {
4173         if (Subtarget.isFP64bit())
4174           return std::make_pair(0U, &Mips::FGR64RegClass);
4175         return std::make_pair(0U, &Mips::AFGR64RegClass);
4176       }
4177       break;
4178     case 'c': // register suitable for indirect jump
4179       if (VT == MVT::i32)
4180         return std::make_pair((unsigned)Mips::T9, &Mips::GPR32RegClass);
4181       if (VT == MVT::i64)
4182         return std::make_pair((unsigned)Mips::T9_64, &Mips::GPR64RegClass);
4183       // This will generate an error message
4184       return std::make_pair(0U, nullptr);
4185     case 'l': // use the `lo` register to store values
4186               // that are no bigger than a word
4187       if (VT == MVT::i32 || VT == MVT::i16 || VT == MVT::i8)
4188         return std::make_pair((unsigned)Mips::LO0, &Mips::LO32RegClass);
4189       return std::make_pair((unsigned)Mips::LO0_64, &Mips::LO64RegClass);
4190     case 'x': // use the concatenated `hi` and `lo` registers
4191               // to store doubleword values
4192       // Fixme: Not triggering the use of both hi and low
4193       // This will generate an error message
4194       return std::make_pair(0U, nullptr);
4195     }
4196   }
4197 
4198   if (!Constraint.empty()) {
4199     std::pair<unsigned, const TargetRegisterClass *> R;
4200     R = parseRegForInlineAsmConstraint(Constraint, VT);
4201 
4202     if (R.second)
4203       return R;
4204   }
4205 
4206   return TargetLowering::getRegForInlineAsmConstraint(TRI, Constraint, VT);
4207 }
4208 
4209 /// LowerAsmOperandForConstraint - Lower the specified operand into the Ops
4210 /// vector.  If it is invalid, don't add anything to Ops.
LowerAsmOperandForConstraint(SDValue Op,StringRef Constraint,std::vector<SDValue> & Ops,SelectionDAG & DAG) const4211 void MipsTargetLowering::LowerAsmOperandForConstraint(SDValue Op,
4212                                                       StringRef Constraint,
4213                                                       std::vector<SDValue> &Ops,
4214                                                       SelectionDAG &DAG) const {
4215   SDLoc DL(Op);
4216   SDValue Result;
4217 
4218   // Only support length 1 constraints for now.
4219   if (Constraint.size() > 1)
4220     return;
4221 
4222   char ConstraintLetter = Constraint[0];
4223   switch (ConstraintLetter) {
4224   default: break; // This will fall through to the generic implementation
4225   case 'I': // Signed 16 bit constant
4226     // If this fails, the parent routine will give an error
4227     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
4228       EVT Type = Op.getValueType();
4229       int64_t Val = C->getSExtValue();
4230       if (isInt<16>(Val)) {
4231         Result = DAG.getTargetConstant(Val, DL, Type);
4232         break;
4233       }
4234     }
4235     return;
4236   case 'J': // integer zero
4237     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
4238       EVT Type = Op.getValueType();
4239       int64_t Val = C->getZExtValue();
4240       if (Val == 0) {
4241         Result = DAG.getTargetConstant(0, DL, Type);
4242         break;
4243       }
4244     }
4245     return;
4246   case 'K': // unsigned 16 bit immediate
4247     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
4248       EVT Type = Op.getValueType();
4249       uint64_t Val = (uint64_t)C->getZExtValue();
4250       if (isUInt<16>(Val)) {
4251         Result = DAG.getTargetConstant(Val, DL, Type);
4252         break;
4253       }
4254     }
4255     return;
4256   case 'L': // signed 32 bit immediate where lower 16 bits are 0
4257     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
4258       EVT Type = Op.getValueType();
4259       int64_t Val = C->getSExtValue();
4260       if ((isInt<32>(Val)) && ((Val & 0xffff) == 0)){
4261         Result = DAG.getTargetConstant(Val, DL, Type);
4262         break;
4263       }
4264     }
4265     return;
4266   case 'N': // immediate in the range of -65535 to -1 (inclusive)
4267     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
4268       EVT Type = Op.getValueType();
4269       int64_t Val = C->getSExtValue();
4270       if ((Val >= -65535) && (Val <= -1)) {
4271         Result = DAG.getTargetConstant(Val, DL, Type);
4272         break;
4273       }
4274     }
4275     return;
4276   case 'O': // signed 15 bit immediate
4277     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
4278       EVT Type = Op.getValueType();
4279       int64_t Val = C->getSExtValue();
4280       if ((isInt<15>(Val))) {
4281         Result = DAG.getTargetConstant(Val, DL, Type);
4282         break;
4283       }
4284     }
4285     return;
4286   case 'P': // immediate in the range of 1 to 65535 (inclusive)
4287     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
4288       EVT Type = Op.getValueType();
4289       int64_t Val = C->getSExtValue();
4290       if ((Val <= 65535) && (Val >= 1)) {
4291         Result = DAG.getTargetConstant(Val, DL, Type);
4292         break;
4293       }
4294     }
4295     return;
4296   }
4297 
4298   if (Result.getNode()) {
4299     Ops.push_back(Result);
4300     return;
4301   }
4302 
4303   TargetLowering::LowerAsmOperandForConstraint(Op, Constraint, Ops, DAG);
4304 }
4305 
isLegalAddressingMode(const DataLayout & DL,const AddrMode & AM,Type * Ty,unsigned AS,Instruction * I) const4306 bool MipsTargetLowering::isLegalAddressingMode(const DataLayout &DL,
4307                                                const AddrMode &AM, Type *Ty,
4308                                                unsigned AS,
4309                                                Instruction *I) const {
4310   // No global is ever allowed as a base.
4311   if (AM.BaseGV)
4312     return false;
4313 
4314   switch (AM.Scale) {
4315   case 0: // "r+i" or just "i", depending on HasBaseReg.
4316     break;
4317   case 1:
4318     if (!AM.HasBaseReg) // allow "r+i".
4319       break;
4320     return false; // disallow "r+r" or "r+r+i".
4321   default:
4322     return false;
4323   }
4324 
4325   return true;
4326 }
4327 
4328 bool
isOffsetFoldingLegal(const GlobalAddressSDNode * GA) const4329 MipsTargetLowering::isOffsetFoldingLegal(const GlobalAddressSDNode *GA) const {
4330   // The Mips target isn't yet aware of offsets.
4331   return false;
4332 }
4333 
getOptimalMemOpType(const MemOp & Op,const AttributeList & FuncAttributes) const4334 EVT MipsTargetLowering::getOptimalMemOpType(
4335     const MemOp &Op, const AttributeList &FuncAttributes) const {
4336   if (Subtarget.hasMips64())
4337     return MVT::i64;
4338 
4339   return MVT::i32;
4340 }
4341 
isFPImmLegal(const APFloat & Imm,EVT VT,bool ForCodeSize) const4342 bool MipsTargetLowering::isFPImmLegal(const APFloat &Imm, EVT VT,
4343                                       bool ForCodeSize) const {
4344   if (VT != MVT::f32 && VT != MVT::f64)
4345     return false;
4346   if (Imm.isNegZero())
4347     return false;
4348   return Imm.isZero();
4349 }
4350 
getJumpTableEncoding() const4351 unsigned MipsTargetLowering::getJumpTableEncoding() const {
4352 
4353   // FIXME: For space reasons this should be: EK_GPRel32BlockAddress.
4354   if (ABI.IsN64() && isPositionIndependent())
4355     return MachineJumpTableInfo::EK_GPRel64BlockAddress;
4356 
4357   return TargetLowering::getJumpTableEncoding();
4358 }
4359 
useSoftFloat() const4360 bool MipsTargetLowering::useSoftFloat() const {
4361   return Subtarget.useSoftFloat();
4362 }
4363 
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) const4364 void MipsTargetLowering::copyByValRegs(
4365     SDValue Chain, const SDLoc &DL, std::vector<SDValue> &OutChains,
4366     SelectionDAG &DAG, const ISD::ArgFlagsTy &Flags,
4367     SmallVectorImpl<SDValue> &InVals, const Argument *FuncArg,
4368     unsigned FirstReg, unsigned LastReg, const CCValAssign &VA,
4369     MipsCCState &State) const {
4370   MachineFunction &MF = DAG.getMachineFunction();
4371   MachineFrameInfo &MFI = MF.getFrameInfo();
4372   unsigned GPRSizeInBytes = Subtarget.getGPRSizeInBytes();
4373   unsigned NumRegs = LastReg - FirstReg;
4374   unsigned RegAreaSize = NumRegs * GPRSizeInBytes;
4375   unsigned FrameObjSize = std::max(Flags.getByValSize(), RegAreaSize);
4376   int FrameObjOffset;
4377   ArrayRef<MCPhysReg> ByValArgRegs = ABI.GetByValArgRegs();
4378 
4379   if (RegAreaSize)
4380     FrameObjOffset =
4381         (int)ABI.GetCalleeAllocdArgSizeInBytes(State.getCallingConv()) -
4382         (int)((ByValArgRegs.size() - FirstReg) * GPRSizeInBytes);
4383   else
4384     FrameObjOffset = VA.getLocMemOffset();
4385 
4386   // Create frame object.
4387   EVT PtrTy = getPointerTy(DAG.getDataLayout());
4388   // Make the fixed object stored to mutable so that the load instructions
4389   // referencing it have their memory dependencies added.
4390   // Set the frame object as isAliased which clears the underlying objects
4391   // vector in ScheduleDAGInstrs::buildSchedGraph() resulting in addition of all
4392   // stores as dependencies for loads referencing this fixed object.
4393   int FI = MFI.CreateFixedObject(FrameObjSize, FrameObjOffset, false, true);
4394   SDValue FIN = DAG.getFrameIndex(FI, PtrTy);
4395   InVals.push_back(FIN);
4396 
4397   if (!NumRegs)
4398     return;
4399 
4400   // Copy arg registers.
4401   MVT RegTy = MVT::getIntegerVT(GPRSizeInBytes * 8);
4402   const TargetRegisterClass *RC = getRegClassFor(RegTy);
4403 
4404   for (unsigned I = 0; I < NumRegs; ++I) {
4405     unsigned ArgReg = ByValArgRegs[FirstReg + I];
4406     unsigned VReg = addLiveIn(MF, ArgReg, RC);
4407     unsigned Offset = I * GPRSizeInBytes;
4408     SDValue StorePtr = DAG.getNode(ISD::ADD, DL, PtrTy, FIN,
4409                                    DAG.getConstant(Offset, DL, PtrTy));
4410     SDValue Store = DAG.getStore(Chain, DL, DAG.getRegister(VReg, RegTy),
4411                                  StorePtr, MachinePointerInfo(FuncArg, Offset));
4412     OutChains.push_back(Store);
4413   }
4414 }
4415 
4416 // 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) const4417 void MipsTargetLowering::passByValArg(
4418     SDValue Chain, const SDLoc &DL,
4419     std::deque<std::pair<unsigned, SDValue>> &RegsToPass,
4420     SmallVectorImpl<SDValue> &MemOpChains, SDValue StackPtr,
4421     MachineFrameInfo &MFI, SelectionDAG &DAG, SDValue Arg, unsigned FirstReg,
4422     unsigned LastReg, const ISD::ArgFlagsTy &Flags, bool isLittle,
4423     const CCValAssign &VA) const {
4424   unsigned ByValSizeInBytes = Flags.getByValSize();
4425   unsigned OffsetInBytes = 0; // From beginning of struct
4426   unsigned RegSizeInBytes = Subtarget.getGPRSizeInBytes();
4427   Align Alignment =
4428       std::min(Flags.getNonZeroByValAlign(), Align(RegSizeInBytes));
4429   EVT PtrTy = getPointerTy(DAG.getDataLayout()),
4430       RegTy = MVT::getIntegerVT(RegSizeInBytes * 8);
4431   unsigned NumRegs = LastReg - FirstReg;
4432 
4433   if (NumRegs) {
4434     ArrayRef<MCPhysReg> ArgRegs = ABI.GetByValArgRegs();
4435     bool LeftoverBytes = (NumRegs * RegSizeInBytes > ByValSizeInBytes);
4436     unsigned I = 0;
4437 
4438     // Copy words to registers.
4439     for (; I < NumRegs - LeftoverBytes; ++I, OffsetInBytes += RegSizeInBytes) {
4440       SDValue LoadPtr = DAG.getNode(ISD::ADD, DL, PtrTy, Arg,
4441                                     DAG.getConstant(OffsetInBytes, DL, PtrTy));
4442       SDValue LoadVal = DAG.getLoad(RegTy, DL, Chain, LoadPtr,
4443                                     MachinePointerInfo(), Alignment);
4444       MemOpChains.push_back(LoadVal.getValue(1));
4445       unsigned ArgReg = ArgRegs[FirstReg + I];
4446       RegsToPass.push_back(std::make_pair(ArgReg, LoadVal));
4447     }
4448 
4449     // Return if the struct has been fully copied.
4450     if (ByValSizeInBytes == OffsetInBytes)
4451       return;
4452 
4453     // Copy the remainder of the byval argument with sub-word loads and shifts.
4454     if (LeftoverBytes) {
4455       SDValue Val;
4456 
4457       for (unsigned LoadSizeInBytes = RegSizeInBytes / 2, TotalBytesLoaded = 0;
4458            OffsetInBytes < ByValSizeInBytes; LoadSizeInBytes /= 2) {
4459         unsigned RemainingSizeInBytes = ByValSizeInBytes - OffsetInBytes;
4460 
4461         if (RemainingSizeInBytes < LoadSizeInBytes)
4462           continue;
4463 
4464         // Load subword.
4465         SDValue LoadPtr = DAG.getNode(ISD::ADD, DL, PtrTy, Arg,
4466                                       DAG.getConstant(OffsetInBytes, DL,
4467                                                       PtrTy));
4468         SDValue LoadVal = DAG.getExtLoad(
4469             ISD::ZEXTLOAD, DL, RegTy, Chain, LoadPtr, MachinePointerInfo(),
4470             MVT::getIntegerVT(LoadSizeInBytes * 8), Alignment);
4471         MemOpChains.push_back(LoadVal.getValue(1));
4472 
4473         // Shift the loaded value.
4474         unsigned Shamt;
4475 
4476         if (isLittle)
4477           Shamt = TotalBytesLoaded * 8;
4478         else
4479           Shamt = (RegSizeInBytes - (TotalBytesLoaded + LoadSizeInBytes)) * 8;
4480 
4481         SDValue Shift = DAG.getNode(ISD::SHL, DL, RegTy, LoadVal,
4482                                     DAG.getConstant(Shamt, DL, MVT::i32));
4483 
4484         if (Val.getNode())
4485           Val = DAG.getNode(ISD::OR, DL, RegTy, Val, Shift);
4486         else
4487           Val = Shift;
4488 
4489         OffsetInBytes += LoadSizeInBytes;
4490         TotalBytesLoaded += LoadSizeInBytes;
4491         Alignment = std::min(Alignment, Align(LoadSizeInBytes));
4492       }
4493 
4494       unsigned ArgReg = ArgRegs[FirstReg + I];
4495       RegsToPass.push_back(std::make_pair(ArgReg, Val));
4496       return;
4497     }
4498   }
4499 
4500   // Copy remainder of byval arg to it with memcpy.
4501   unsigned MemCpySize = ByValSizeInBytes - OffsetInBytes;
4502   SDValue Src = DAG.getNode(ISD::ADD, DL, PtrTy, Arg,
4503                             DAG.getConstant(OffsetInBytes, DL, PtrTy));
4504   SDValue Dst = DAG.getNode(ISD::ADD, DL, PtrTy, StackPtr,
4505                             DAG.getIntPtrConstant(VA.getLocMemOffset(), DL));
4506   Chain = DAG.getMemcpy(
4507       Chain, DL, Dst, Src, DAG.getConstant(MemCpySize, DL, PtrTy),
4508       Align(Alignment), /*isVolatile=*/false, /*AlwaysInline=*/false,
4509       /*CI=*/nullptr, std::nullopt, MachinePointerInfo(), MachinePointerInfo());
4510   MemOpChains.push_back(Chain);
4511 }
4512 
writeVarArgRegs(std::vector<SDValue> & OutChains,SDValue Chain,const SDLoc & DL,SelectionDAG & DAG,CCState & State) const4513 void MipsTargetLowering::writeVarArgRegs(std::vector<SDValue> &OutChains,
4514                                          SDValue Chain, const SDLoc &DL,
4515                                          SelectionDAG &DAG,
4516                                          CCState &State) const {
4517   ArrayRef<MCPhysReg> ArgRegs = ABI.GetVarArgRegs();
4518   unsigned Idx = State.getFirstUnallocated(ArgRegs);
4519   unsigned RegSizeInBytes = Subtarget.getGPRSizeInBytes();
4520   MVT RegTy = MVT::getIntegerVT(RegSizeInBytes * 8);
4521   const TargetRegisterClass *RC = getRegClassFor(RegTy);
4522   MachineFunction &MF = DAG.getMachineFunction();
4523   MachineFrameInfo &MFI = MF.getFrameInfo();
4524   MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
4525 
4526   // Offset of the first variable argument from stack pointer.
4527   int VaArgOffset;
4528 
4529   if (ArgRegs.size() == Idx)
4530     VaArgOffset = alignTo(State.getStackSize(), RegSizeInBytes);
4531   else {
4532     VaArgOffset =
4533         (int)ABI.GetCalleeAllocdArgSizeInBytes(State.getCallingConv()) -
4534         (int)(RegSizeInBytes * (ArgRegs.size() - Idx));
4535   }
4536 
4537   // Record the frame index of the first variable argument
4538   // which is a value necessary to VASTART.
4539   int FI = MFI.CreateFixedObject(RegSizeInBytes, VaArgOffset, true);
4540   MipsFI->setVarArgsFrameIndex(FI);
4541 
4542   // Copy the integer registers that have not been used for argument passing
4543   // to the argument register save area. For O32, the save area is allocated
4544   // in the caller's stack frame, while for N32/64, it is allocated in the
4545   // callee's stack frame.
4546   for (unsigned I = Idx; I < ArgRegs.size();
4547        ++I, VaArgOffset += RegSizeInBytes) {
4548     unsigned Reg = addLiveIn(MF, ArgRegs[I], RC);
4549     SDValue ArgValue = DAG.getCopyFromReg(Chain, DL, Reg, RegTy);
4550     FI = MFI.CreateFixedObject(RegSizeInBytes, VaArgOffset, true);
4551     SDValue PtrOff = DAG.getFrameIndex(FI, getPointerTy(DAG.getDataLayout()));
4552     SDValue Store =
4553         DAG.getStore(Chain, DL, ArgValue, PtrOff, MachinePointerInfo());
4554     cast<StoreSDNode>(Store.getNode())->getMemOperand()->setValue(
4555         (Value *)nullptr);
4556     OutChains.push_back(Store);
4557   }
4558 }
4559 
HandleByVal(CCState * State,unsigned & Size,Align Alignment) const4560 void MipsTargetLowering::HandleByVal(CCState *State, unsigned &Size,
4561                                      Align Alignment) const {
4562   const TargetFrameLowering *TFL = Subtarget.getFrameLowering();
4563 
4564   assert(Size && "Byval argument's size shouldn't be 0.");
4565 
4566   Alignment = std::min(Alignment, TFL->getStackAlign());
4567 
4568   unsigned FirstReg = 0;
4569   unsigned NumRegs = 0;
4570 
4571   if (State->getCallingConv() != CallingConv::Fast) {
4572     unsigned RegSizeInBytes = Subtarget.getGPRSizeInBytes();
4573     ArrayRef<MCPhysReg> IntArgRegs = ABI.GetByValArgRegs();
4574     // FIXME: The O32 case actually describes no shadow registers.
4575     const MCPhysReg *ShadowRegs =
4576         ABI.IsO32() ? IntArgRegs.data() : Mips64DPRegs;
4577 
4578     // We used to check the size as well but we can't do that anymore since
4579     // CCState::HandleByVal() rounds up the size after calling this function.
4580     assert(
4581         Alignment >= Align(RegSizeInBytes) &&
4582         "Byval argument's alignment should be a multiple of RegSizeInBytes.");
4583 
4584     FirstReg = State->getFirstUnallocated(IntArgRegs);
4585 
4586     // If Alignment > RegSizeInBytes, the first arg register must be even.
4587     // FIXME: This condition happens to do the right thing but it's not the
4588     //        right way to test it. We want to check that the stack frame offset
4589     //        of the register is aligned.
4590     if ((Alignment > RegSizeInBytes) && (FirstReg % 2)) {
4591       State->AllocateReg(IntArgRegs[FirstReg], ShadowRegs[FirstReg]);
4592       ++FirstReg;
4593     }
4594 
4595     // Mark the registers allocated.
4596     Size = alignTo(Size, RegSizeInBytes);
4597     for (unsigned I = FirstReg; Size > 0 && (I < IntArgRegs.size());
4598          Size -= RegSizeInBytes, ++I, ++NumRegs)
4599       State->AllocateReg(IntArgRegs[I], ShadowRegs[I]);
4600   }
4601 
4602   State->addInRegsParamInfo(FirstReg, FirstReg + NumRegs);
4603 }
4604 
emitPseudoSELECT(MachineInstr & MI,MachineBasicBlock * BB,bool isFPCmp,unsigned Opc) const4605 MachineBasicBlock *MipsTargetLowering::emitPseudoSELECT(MachineInstr &MI,
4606                                                         MachineBasicBlock *BB,
4607                                                         bool isFPCmp,
4608                                                         unsigned Opc) const {
4609   assert(!(Subtarget.hasMips4() || Subtarget.hasMips32()) &&
4610          "Subtarget already supports SELECT nodes with the use of"
4611          "conditional-move instructions.");
4612 
4613   const TargetInstrInfo *TII =
4614       Subtarget.getInstrInfo();
4615   DebugLoc DL = MI.getDebugLoc();
4616 
4617   // To "insert" a SELECT instruction, we actually have to insert the
4618   // diamond control-flow pattern.  The incoming instruction knows the
4619   // destination vreg to set, the condition code register to branch on, the
4620   // true/false values to select between, and a branch opcode to use.
4621   const BasicBlock *LLVM_BB = BB->getBasicBlock();
4622   MachineFunction::iterator It = ++BB->getIterator();
4623 
4624   //  thisMBB:
4625   //  ...
4626   //   TrueVal = ...
4627   //   setcc r1, r2, r3
4628   //   bNE   r1, r0, copy1MBB
4629   //   fallthrough --> copy0MBB
4630   MachineBasicBlock *thisMBB  = BB;
4631   MachineFunction *F = BB->getParent();
4632   MachineBasicBlock *copy0MBB = F->CreateMachineBasicBlock(LLVM_BB);
4633   MachineBasicBlock *sinkMBB  = F->CreateMachineBasicBlock(LLVM_BB);
4634   F->insert(It, copy0MBB);
4635   F->insert(It, sinkMBB);
4636 
4637   // Transfer the remainder of BB and its successor edges to sinkMBB.
4638   sinkMBB->splice(sinkMBB->begin(), BB,
4639                   std::next(MachineBasicBlock::iterator(MI)), BB->end());
4640   sinkMBB->transferSuccessorsAndUpdatePHIs(BB);
4641 
4642   // Next, add the true and fallthrough blocks as its successors.
4643   BB->addSuccessor(copy0MBB);
4644   BB->addSuccessor(sinkMBB);
4645 
4646   if (isFPCmp) {
4647     // bc1[tf] cc, sinkMBB
4648     BuildMI(BB, DL, TII->get(Opc))
4649         .addReg(MI.getOperand(1).getReg())
4650         .addMBB(sinkMBB);
4651   } else {
4652     // bne rs, $0, sinkMBB
4653     BuildMI(BB, DL, TII->get(Opc))
4654         .addReg(MI.getOperand(1).getReg())
4655         .addReg(Mips::ZERO)
4656         .addMBB(sinkMBB);
4657   }
4658 
4659   //  copy0MBB:
4660   //   %FalseValue = ...
4661   //   # fallthrough to sinkMBB
4662   BB = copy0MBB;
4663 
4664   // Update machine-CFG edges
4665   BB->addSuccessor(sinkMBB);
4666 
4667   //  sinkMBB:
4668   //   %Result = phi [ %TrueValue, thisMBB ], [ %FalseValue, copy0MBB ]
4669   //  ...
4670   BB = sinkMBB;
4671 
4672   BuildMI(*BB, BB->begin(), DL, TII->get(Mips::PHI), MI.getOperand(0).getReg())
4673       .addReg(MI.getOperand(2).getReg())
4674       .addMBB(thisMBB)
4675       .addReg(MI.getOperand(3).getReg())
4676       .addMBB(copy0MBB);
4677 
4678   MI.eraseFromParent(); // The pseudo instruction is gone now.
4679 
4680   return BB;
4681 }
4682 
4683 MachineBasicBlock *
emitPseudoD_SELECT(MachineInstr & MI,MachineBasicBlock * BB) const4684 MipsTargetLowering::emitPseudoD_SELECT(MachineInstr &MI,
4685                                        MachineBasicBlock *BB) const {
4686   assert(!(Subtarget.hasMips4() || Subtarget.hasMips32()) &&
4687          "Subtarget already supports SELECT nodes with the use of"
4688          "conditional-move instructions.");
4689 
4690   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
4691   DebugLoc DL = MI.getDebugLoc();
4692 
4693   // D_SELECT substitutes two SELECT nodes that goes one after another and
4694   // have the same condition operand. On machines which don't have
4695   // conditional-move instruction, it reduces unnecessary branch instructions
4696   // which are result of using two diamond patterns that are result of two
4697   // SELECT pseudo instructions.
4698   const BasicBlock *LLVM_BB = BB->getBasicBlock();
4699   MachineFunction::iterator It = ++BB->getIterator();
4700 
4701   //  thisMBB:
4702   //  ...
4703   //   TrueVal = ...
4704   //   setcc r1, r2, r3
4705   //   bNE   r1, r0, copy1MBB
4706   //   fallthrough --> copy0MBB
4707   MachineBasicBlock *thisMBB = BB;
4708   MachineFunction *F = BB->getParent();
4709   MachineBasicBlock *copy0MBB = F->CreateMachineBasicBlock(LLVM_BB);
4710   MachineBasicBlock *sinkMBB = F->CreateMachineBasicBlock(LLVM_BB);
4711   F->insert(It, copy0MBB);
4712   F->insert(It, sinkMBB);
4713 
4714   // Transfer the remainder of BB and its successor edges to sinkMBB.
4715   sinkMBB->splice(sinkMBB->begin(), BB,
4716                   std::next(MachineBasicBlock::iterator(MI)), BB->end());
4717   sinkMBB->transferSuccessorsAndUpdatePHIs(BB);
4718 
4719   // Next, add the true and fallthrough blocks as its successors.
4720   BB->addSuccessor(copy0MBB);
4721   BB->addSuccessor(sinkMBB);
4722 
4723   // bne rs, $0, sinkMBB
4724   BuildMI(BB, DL, TII->get(Mips::BNE))
4725       .addReg(MI.getOperand(2).getReg())
4726       .addReg(Mips::ZERO)
4727       .addMBB(sinkMBB);
4728 
4729   //  copy0MBB:
4730   //   %FalseValue = ...
4731   //   # fallthrough to sinkMBB
4732   BB = copy0MBB;
4733 
4734   // Update machine-CFG edges
4735   BB->addSuccessor(sinkMBB);
4736 
4737   //  sinkMBB:
4738   //   %Result = phi [ %TrueValue, thisMBB ], [ %FalseValue, copy0MBB ]
4739   //  ...
4740   BB = sinkMBB;
4741 
4742   // Use two PHI nodes to select two reults
4743   BuildMI(*BB, BB->begin(), DL, TII->get(Mips::PHI), MI.getOperand(0).getReg())
4744       .addReg(MI.getOperand(3).getReg())
4745       .addMBB(thisMBB)
4746       .addReg(MI.getOperand(5).getReg())
4747       .addMBB(copy0MBB);
4748   BuildMI(*BB, BB->begin(), DL, TII->get(Mips::PHI), MI.getOperand(1).getReg())
4749       .addReg(MI.getOperand(4).getReg())
4750       .addMBB(thisMBB)
4751       .addReg(MI.getOperand(6).getReg())
4752       .addMBB(copy0MBB);
4753 
4754   MI.eraseFromParent(); // The pseudo instruction is gone now.
4755 
4756   return BB;
4757 }
4758 
4759 // FIXME? Maybe this could be a TableGen attribute on some registers and
4760 // this table could be generated automatically from RegInfo.
4761 Register
getRegisterByName(const char * RegName,LLT VT,const MachineFunction & MF) const4762 MipsTargetLowering::getRegisterByName(const char *RegName, LLT VT,
4763                                       const MachineFunction &MF) const {
4764   // The Linux kernel uses $28 and sp.
4765   if (Subtarget.isGP64bit()) {
4766     Register Reg = StringSwitch<Register>(RegName)
4767                        .Case("$28", Mips::GP_64)
4768                        .Case("sp", Mips::SP_64)
4769                        .Default(Register());
4770     if (Reg)
4771       return Reg;
4772   } else {
4773     Register Reg = StringSwitch<Register>(RegName)
4774                        .Case("$28", Mips::GP)
4775                        .Case("sp", Mips::SP)
4776                        .Default(Register());
4777     if (Reg)
4778       return Reg;
4779   }
4780   report_fatal_error("Invalid register name global variable");
4781 }
4782 
emitLDR_W(MachineInstr & MI,MachineBasicBlock * BB) const4783 MachineBasicBlock *MipsTargetLowering::emitLDR_W(MachineInstr &MI,
4784                                                  MachineBasicBlock *BB) const {
4785   MachineFunction *MF = BB->getParent();
4786   MachineRegisterInfo &MRI = MF->getRegInfo();
4787   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
4788   const bool IsLittle = Subtarget.isLittle();
4789   DebugLoc DL = MI.getDebugLoc();
4790 
4791   Register Dest = MI.getOperand(0).getReg();
4792   Register Address = MI.getOperand(1).getReg();
4793   unsigned Imm = MI.getOperand(2).getImm();
4794 
4795   MachineBasicBlock::iterator I(MI);
4796 
4797   if (Subtarget.hasMips32r6() || Subtarget.hasMips64r6()) {
4798     // Mips release 6 can load from adress that is not naturally-aligned.
4799     Register Temp = MRI.createVirtualRegister(&Mips::GPR32RegClass);
4800     BuildMI(*BB, I, DL, TII->get(Mips::LW))
4801         .addDef(Temp)
4802         .addUse(Address)
4803         .addImm(Imm);
4804     BuildMI(*BB, I, DL, TII->get(Mips::FILL_W)).addDef(Dest).addUse(Temp);
4805   } else {
4806     // Mips release 5 needs to use instructions that can load from an unaligned
4807     // memory address.
4808     Register LoadHalf = MRI.createVirtualRegister(&Mips::GPR32RegClass);
4809     Register LoadFull = MRI.createVirtualRegister(&Mips::GPR32RegClass);
4810     Register Undef = MRI.createVirtualRegister(&Mips::GPR32RegClass);
4811     BuildMI(*BB, I, DL, TII->get(Mips::IMPLICIT_DEF)).addDef(Undef);
4812     BuildMI(*BB, I, DL, TII->get(Mips::LWR))
4813         .addDef(LoadHalf)
4814         .addUse(Address)
4815         .addImm(Imm + (IsLittle ? 0 : 3))
4816         .addUse(Undef);
4817     BuildMI(*BB, I, DL, TII->get(Mips::LWL))
4818         .addDef(LoadFull)
4819         .addUse(Address)
4820         .addImm(Imm + (IsLittle ? 3 : 0))
4821         .addUse(LoadHalf);
4822     BuildMI(*BB, I, DL, TII->get(Mips::FILL_W)).addDef(Dest).addUse(LoadFull);
4823   }
4824 
4825   MI.eraseFromParent();
4826   return BB;
4827 }
4828 
emitLDR_D(MachineInstr & MI,MachineBasicBlock * BB) const4829 MachineBasicBlock *MipsTargetLowering::emitLDR_D(MachineInstr &MI,
4830                                                  MachineBasicBlock *BB) const {
4831   MachineFunction *MF = BB->getParent();
4832   MachineRegisterInfo &MRI = MF->getRegInfo();
4833   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
4834   const bool IsLittle = Subtarget.isLittle();
4835   DebugLoc DL = MI.getDebugLoc();
4836 
4837   Register Dest = MI.getOperand(0).getReg();
4838   Register Address = MI.getOperand(1).getReg();
4839   unsigned Imm = MI.getOperand(2).getImm();
4840 
4841   MachineBasicBlock::iterator I(MI);
4842 
4843   if (Subtarget.hasMips32r6() || Subtarget.hasMips64r6()) {
4844     // Mips release 6 can load from adress that is not naturally-aligned.
4845     if (Subtarget.isGP64bit()) {
4846       Register Temp = MRI.createVirtualRegister(&Mips::GPR64RegClass);
4847       BuildMI(*BB, I, DL, TII->get(Mips::LD))
4848           .addDef(Temp)
4849           .addUse(Address)
4850           .addImm(Imm);
4851       BuildMI(*BB, I, DL, TII->get(Mips::FILL_D)).addDef(Dest).addUse(Temp);
4852     } else {
4853       Register Wtemp = MRI.createVirtualRegister(&Mips::MSA128WRegClass);
4854       Register Lo = MRI.createVirtualRegister(&Mips::GPR32RegClass);
4855       Register Hi = MRI.createVirtualRegister(&Mips::GPR32RegClass);
4856       BuildMI(*BB, I, DL, TII->get(Mips::LW))
4857           .addDef(Lo)
4858           .addUse(Address)
4859           .addImm(Imm + (IsLittle ? 0 : 4));
4860       BuildMI(*BB, I, DL, TII->get(Mips::LW))
4861           .addDef(Hi)
4862           .addUse(Address)
4863           .addImm(Imm + (IsLittle ? 4 : 0));
4864       BuildMI(*BB, I, DL, TII->get(Mips::FILL_W)).addDef(Wtemp).addUse(Lo);
4865       BuildMI(*BB, I, DL, TII->get(Mips::INSERT_W), Dest)
4866           .addUse(Wtemp)
4867           .addUse(Hi)
4868           .addImm(1);
4869     }
4870   } else {
4871     // Mips release 5 needs to use instructions that can load from an unaligned
4872     // memory address.
4873     Register LoHalf = MRI.createVirtualRegister(&Mips::GPR32RegClass);
4874     Register LoFull = MRI.createVirtualRegister(&Mips::GPR32RegClass);
4875     Register LoUndef = MRI.createVirtualRegister(&Mips::GPR32RegClass);
4876     Register HiHalf = MRI.createVirtualRegister(&Mips::GPR32RegClass);
4877     Register HiFull = MRI.createVirtualRegister(&Mips::GPR32RegClass);
4878     Register HiUndef = MRI.createVirtualRegister(&Mips::GPR32RegClass);
4879     Register Wtemp = MRI.createVirtualRegister(&Mips::MSA128WRegClass);
4880     BuildMI(*BB, I, DL, TII->get(Mips::IMPLICIT_DEF)).addDef(LoUndef);
4881     BuildMI(*BB, I, DL, TII->get(Mips::LWR))
4882         .addDef(LoHalf)
4883         .addUse(Address)
4884         .addImm(Imm + (IsLittle ? 0 : 7))
4885         .addUse(LoUndef);
4886     BuildMI(*BB, I, DL, TII->get(Mips::LWL))
4887         .addDef(LoFull)
4888         .addUse(Address)
4889         .addImm(Imm + (IsLittle ? 3 : 4))
4890         .addUse(LoHalf);
4891     BuildMI(*BB, I, DL, TII->get(Mips::IMPLICIT_DEF)).addDef(HiUndef);
4892     BuildMI(*BB, I, DL, TII->get(Mips::LWR))
4893         .addDef(HiHalf)
4894         .addUse(Address)
4895         .addImm(Imm + (IsLittle ? 4 : 3))
4896         .addUse(HiUndef);
4897     BuildMI(*BB, I, DL, TII->get(Mips::LWL))
4898         .addDef(HiFull)
4899         .addUse(Address)
4900         .addImm(Imm + (IsLittle ? 7 : 0))
4901         .addUse(HiHalf);
4902     BuildMI(*BB, I, DL, TII->get(Mips::FILL_W)).addDef(Wtemp).addUse(LoFull);
4903     BuildMI(*BB, I, DL, TII->get(Mips::INSERT_W), Dest)
4904         .addUse(Wtemp)
4905         .addUse(HiFull)
4906         .addImm(1);
4907   }
4908 
4909   MI.eraseFromParent();
4910   return BB;
4911 }
4912 
emitSTR_W(MachineInstr & MI,MachineBasicBlock * BB) const4913 MachineBasicBlock *MipsTargetLowering::emitSTR_W(MachineInstr &MI,
4914                                                  MachineBasicBlock *BB) const {
4915   MachineFunction *MF = BB->getParent();
4916   MachineRegisterInfo &MRI = MF->getRegInfo();
4917   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
4918   const bool IsLittle = Subtarget.isLittle();
4919   DebugLoc DL = MI.getDebugLoc();
4920 
4921   Register StoreVal = MI.getOperand(0).getReg();
4922   Register Address = MI.getOperand(1).getReg();
4923   unsigned Imm = MI.getOperand(2).getImm();
4924 
4925   MachineBasicBlock::iterator I(MI);
4926 
4927   if (Subtarget.hasMips32r6() || Subtarget.hasMips64r6()) {
4928     // Mips release 6 can store to adress that is not naturally-aligned.
4929     Register BitcastW = MRI.createVirtualRegister(&Mips::MSA128WRegClass);
4930     Register Tmp = MRI.createVirtualRegister(&Mips::GPR32RegClass);
4931     BuildMI(*BB, I, DL, TII->get(Mips::COPY)).addDef(BitcastW).addUse(StoreVal);
4932     BuildMI(*BB, I, DL, TII->get(Mips::COPY_S_W))
4933         .addDef(Tmp)
4934         .addUse(BitcastW)
4935         .addImm(0);
4936     BuildMI(*BB, I, DL, TII->get(Mips::SW))
4937         .addUse(Tmp)
4938         .addUse(Address)
4939         .addImm(Imm);
4940   } else {
4941     // Mips release 5 needs to use instructions that can store to an unaligned
4942     // memory address.
4943     Register Tmp = MRI.createVirtualRegister(&Mips::GPR32RegClass);
4944     BuildMI(*BB, I, DL, TII->get(Mips::COPY_S_W))
4945         .addDef(Tmp)
4946         .addUse(StoreVal)
4947         .addImm(0);
4948     BuildMI(*BB, I, DL, TII->get(Mips::SWR))
4949         .addUse(Tmp)
4950         .addUse(Address)
4951         .addImm(Imm + (IsLittle ? 0 : 3));
4952     BuildMI(*BB, I, DL, TII->get(Mips::SWL))
4953         .addUse(Tmp)
4954         .addUse(Address)
4955         .addImm(Imm + (IsLittle ? 3 : 0));
4956   }
4957 
4958   MI.eraseFromParent();
4959 
4960   return BB;
4961 }
4962 
emitSTR_D(MachineInstr & MI,MachineBasicBlock * BB) const4963 MachineBasicBlock *MipsTargetLowering::emitSTR_D(MachineInstr &MI,
4964                                                  MachineBasicBlock *BB) const {
4965   MachineFunction *MF = BB->getParent();
4966   MachineRegisterInfo &MRI = MF->getRegInfo();
4967   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
4968   const bool IsLittle = Subtarget.isLittle();
4969   DebugLoc DL = MI.getDebugLoc();
4970 
4971   Register StoreVal = MI.getOperand(0).getReg();
4972   Register Address = MI.getOperand(1).getReg();
4973   unsigned Imm = MI.getOperand(2).getImm();
4974 
4975   MachineBasicBlock::iterator I(MI);
4976 
4977   if (Subtarget.hasMips32r6() || Subtarget.hasMips64r6()) {
4978     // Mips release 6 can store to adress that is not naturally-aligned.
4979     if (Subtarget.isGP64bit()) {
4980       Register BitcastD = MRI.createVirtualRegister(&Mips::MSA128DRegClass);
4981       Register Lo = MRI.createVirtualRegister(&Mips::GPR64RegClass);
4982       BuildMI(*BB, I, DL, TII->get(Mips::COPY))
4983           .addDef(BitcastD)
4984           .addUse(StoreVal);
4985       BuildMI(*BB, I, DL, TII->get(Mips::COPY_S_D))
4986           .addDef(Lo)
4987           .addUse(BitcastD)
4988           .addImm(0);
4989       BuildMI(*BB, I, DL, TII->get(Mips::SD))
4990           .addUse(Lo)
4991           .addUse(Address)
4992           .addImm(Imm);
4993     } else {
4994       Register BitcastW = MRI.createVirtualRegister(&Mips::MSA128WRegClass);
4995       Register Lo = MRI.createVirtualRegister(&Mips::GPR32RegClass);
4996       Register Hi = MRI.createVirtualRegister(&Mips::GPR32RegClass);
4997       BuildMI(*BB, I, DL, TII->get(Mips::COPY))
4998           .addDef(BitcastW)
4999           .addUse(StoreVal);
5000       BuildMI(*BB, I, DL, TII->get(Mips::COPY_S_W))
5001           .addDef(Lo)
5002           .addUse(BitcastW)
5003           .addImm(0);
5004       BuildMI(*BB, I, DL, TII->get(Mips::COPY_S_W))
5005           .addDef(Hi)
5006           .addUse(BitcastW)
5007           .addImm(1);
5008       BuildMI(*BB, I, DL, TII->get(Mips::SW))
5009           .addUse(Lo)
5010           .addUse(Address)
5011           .addImm(Imm + (IsLittle ? 0 : 4));
5012       BuildMI(*BB, I, DL, TII->get(Mips::SW))
5013           .addUse(Hi)
5014           .addUse(Address)
5015           .addImm(Imm + (IsLittle ? 4 : 0));
5016     }
5017   } else {
5018     // Mips release 5 needs to use instructions that can store to an unaligned
5019     // memory address.
5020     Register Bitcast = MRI.createVirtualRegister(&Mips::MSA128WRegClass);
5021     Register Lo = MRI.createVirtualRegister(&Mips::GPR32RegClass);
5022     Register Hi = MRI.createVirtualRegister(&Mips::GPR32RegClass);
5023     BuildMI(*BB, I, DL, TII->get(Mips::COPY)).addDef(Bitcast).addUse(StoreVal);
5024     BuildMI(*BB, I, DL, TII->get(Mips::COPY_S_W))
5025         .addDef(Lo)
5026         .addUse(Bitcast)
5027         .addImm(0);
5028     BuildMI(*BB, I, DL, TII->get(Mips::COPY_S_W))
5029         .addDef(Hi)
5030         .addUse(Bitcast)
5031         .addImm(1);
5032     BuildMI(*BB, I, DL, TII->get(Mips::SWR))
5033         .addUse(Lo)
5034         .addUse(Address)
5035         .addImm(Imm + (IsLittle ? 0 : 3));
5036     BuildMI(*BB, I, DL, TII->get(Mips::SWL))
5037         .addUse(Lo)
5038         .addUse(Address)
5039         .addImm(Imm + (IsLittle ? 3 : 0));
5040     BuildMI(*BB, I, DL, TII->get(Mips::SWR))
5041         .addUse(Hi)
5042         .addUse(Address)
5043         .addImm(Imm + (IsLittle ? 4 : 7));
5044     BuildMI(*BB, I, DL, TII->get(Mips::SWL))
5045         .addUse(Hi)
5046         .addUse(Address)
5047         .addImm(Imm + (IsLittle ? 7 : 4));
5048   }
5049 
5050   MI.eraseFromParent();
5051   return BB;
5052 }
5053