xref: /freebsd/contrib/llvm-project/llvm/lib/Target/Mips/Mips16ISelLowering.cpp (revision e40139ff33b48b56a24c808b166b04b8ee6f5b21)
1 //===-- Mips16ISelLowering.h - Mips16 DAG Lowering Interface ----*- C++ -*-===//
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 // Subclass of MipsTargetLowering specialized for mips16.
10 //
11 //===----------------------------------------------------------------------===//
12 #include "Mips16ISelLowering.h"
13 #include "MCTargetDesc/MipsBaseInfo.h"
14 #include "Mips16HardFloatInfo.h"
15 #include "MipsMachineFunction.h"
16 #include "MipsRegisterInfo.h"
17 #include "MipsTargetMachine.h"
18 #include "llvm/CodeGen/MachineInstrBuilder.h"
19 #include "llvm/CodeGen/TargetInstrInfo.h"
20 #include "llvm/Support/CommandLine.h"
21 
22 using namespace llvm;
23 
24 #define DEBUG_TYPE "mips-lower"
25 
26 static cl::opt<bool> DontExpandCondPseudos16(
27   "mips16-dont-expand-cond-pseudo",
28   cl::init(false),
29   cl::desc("Don't expand conditional move related "
30            "pseudos for Mips 16"),
31   cl::Hidden);
32 
33 namespace {
34 struct Mips16Libcall {
35   RTLIB::Libcall Libcall;
36   const char *Name;
37 
38   bool operator<(const Mips16Libcall &RHS) const {
39     return std::strcmp(Name, RHS.Name) < 0;
40   }
41 };
42 
43 struct Mips16IntrinsicHelperType{
44   const char* Name;
45   const char* Helper;
46 
47   bool operator<(const Mips16IntrinsicHelperType &RHS) const {
48     return std::strcmp(Name, RHS.Name) < 0;
49   }
50   bool operator==(const Mips16IntrinsicHelperType &RHS) const {
51     return std::strcmp(Name, RHS.Name) == 0;
52   }
53 };
54 }
55 
56 // Libcalls for which no helper is generated. Sorted by name for binary search.
57 static const Mips16Libcall HardFloatLibCalls[] = {
58   { RTLIB::ADD_F64, "__mips16_adddf3" },
59   { RTLIB::ADD_F32, "__mips16_addsf3" },
60   { RTLIB::DIV_F64, "__mips16_divdf3" },
61   { RTLIB::DIV_F32, "__mips16_divsf3" },
62   { RTLIB::OEQ_F64, "__mips16_eqdf2" },
63   { RTLIB::OEQ_F32, "__mips16_eqsf2" },
64   { RTLIB::FPEXT_F32_F64, "__mips16_extendsfdf2" },
65   { RTLIB::FPTOSINT_F64_I32, "__mips16_fix_truncdfsi" },
66   { RTLIB::FPTOSINT_F32_I32, "__mips16_fix_truncsfsi" },
67   { RTLIB::SINTTOFP_I32_F64, "__mips16_floatsidf" },
68   { RTLIB::SINTTOFP_I32_F32, "__mips16_floatsisf" },
69   { RTLIB::UINTTOFP_I32_F64, "__mips16_floatunsidf" },
70   { RTLIB::UINTTOFP_I32_F32, "__mips16_floatunsisf" },
71   { RTLIB::OGE_F64, "__mips16_gedf2" },
72   { RTLIB::OGE_F32, "__mips16_gesf2" },
73   { RTLIB::OGT_F64, "__mips16_gtdf2" },
74   { RTLIB::OGT_F32, "__mips16_gtsf2" },
75   { RTLIB::OLE_F64, "__mips16_ledf2" },
76   { RTLIB::OLE_F32, "__mips16_lesf2" },
77   { RTLIB::OLT_F64, "__mips16_ltdf2" },
78   { RTLIB::OLT_F32, "__mips16_ltsf2" },
79   { RTLIB::MUL_F64, "__mips16_muldf3" },
80   { RTLIB::MUL_F32, "__mips16_mulsf3" },
81   { RTLIB::UNE_F64, "__mips16_nedf2" },
82   { RTLIB::UNE_F32, "__mips16_nesf2" },
83   { RTLIB::UNKNOWN_LIBCALL, "__mips16_ret_dc" }, // No associated libcall.
84   { RTLIB::UNKNOWN_LIBCALL, "__mips16_ret_df" }, // No associated libcall.
85   { RTLIB::UNKNOWN_LIBCALL, "__mips16_ret_sc" }, // No associated libcall.
86   { RTLIB::UNKNOWN_LIBCALL, "__mips16_ret_sf" }, // No associated libcall.
87   { RTLIB::SUB_F64, "__mips16_subdf3" },
88   { RTLIB::SUB_F32, "__mips16_subsf3" },
89   { RTLIB::FPROUND_F64_F32, "__mips16_truncdfsf2" },
90   { RTLIB::UO_F64, "__mips16_unorddf2" },
91   { RTLIB::UO_F32, "__mips16_unordsf2" }
92 };
93 
94 static const Mips16IntrinsicHelperType Mips16IntrinsicHelper[] = {
95   {"__fixunsdfsi", "__mips16_call_stub_2" },
96   {"ceil",  "__mips16_call_stub_df_2"},
97   {"ceilf", "__mips16_call_stub_sf_1"},
98   {"copysign",  "__mips16_call_stub_df_10"},
99   {"copysignf", "__mips16_call_stub_sf_5"},
100   {"cos",  "__mips16_call_stub_df_2"},
101   {"cosf", "__mips16_call_stub_sf_1"},
102   {"exp2",  "__mips16_call_stub_df_2"},
103   {"exp2f", "__mips16_call_stub_sf_1"},
104   {"floor",  "__mips16_call_stub_df_2"},
105   {"floorf", "__mips16_call_stub_sf_1"},
106   {"log2",  "__mips16_call_stub_df_2"},
107   {"log2f", "__mips16_call_stub_sf_1"},
108   {"nearbyint",  "__mips16_call_stub_df_2"},
109   {"nearbyintf", "__mips16_call_stub_sf_1"},
110   {"rint",  "__mips16_call_stub_df_2"},
111   {"rintf", "__mips16_call_stub_sf_1"},
112   {"sin",  "__mips16_call_stub_df_2"},
113   {"sinf", "__mips16_call_stub_sf_1"},
114   {"sqrt",  "__mips16_call_stub_df_2"},
115   {"sqrtf", "__mips16_call_stub_sf_1"},
116   {"trunc",  "__mips16_call_stub_df_2"},
117   {"truncf", "__mips16_call_stub_sf_1"},
118 };
119 
120 Mips16TargetLowering::Mips16TargetLowering(const MipsTargetMachine &TM,
121                                            const MipsSubtarget &STI)
122     : MipsTargetLowering(TM, STI) {
123 
124   // Set up the register classes
125   addRegisterClass(MVT::i32, &Mips::CPU16RegsRegClass);
126 
127   if (!Subtarget.useSoftFloat())
128     setMips16HardFloatLibCalls();
129 
130   setOperationAction(ISD::ATOMIC_FENCE,       MVT::Other, Expand);
131   setOperationAction(ISD::ATOMIC_CMP_SWAP,    MVT::i32,   Expand);
132   setOperationAction(ISD::ATOMIC_SWAP,        MVT::i32,   Expand);
133   setOperationAction(ISD::ATOMIC_LOAD_ADD,    MVT::i32,   Expand);
134   setOperationAction(ISD::ATOMIC_LOAD_SUB,    MVT::i32,   Expand);
135   setOperationAction(ISD::ATOMIC_LOAD_AND,    MVT::i32,   Expand);
136   setOperationAction(ISD::ATOMIC_LOAD_OR,     MVT::i32,   Expand);
137   setOperationAction(ISD::ATOMIC_LOAD_XOR,    MVT::i32,   Expand);
138   setOperationAction(ISD::ATOMIC_LOAD_NAND,   MVT::i32,   Expand);
139   setOperationAction(ISD::ATOMIC_LOAD_MIN,    MVT::i32,   Expand);
140   setOperationAction(ISD::ATOMIC_LOAD_MAX,    MVT::i32,   Expand);
141   setOperationAction(ISD::ATOMIC_LOAD_UMIN,   MVT::i32,   Expand);
142   setOperationAction(ISD::ATOMIC_LOAD_UMAX,   MVT::i32,   Expand);
143 
144   setOperationAction(ISD::ROTR, MVT::i32,  Expand);
145   setOperationAction(ISD::ROTR, MVT::i64,  Expand);
146   setOperationAction(ISD::BSWAP, MVT::i32, Expand);
147   setOperationAction(ISD::BSWAP, MVT::i64, Expand);
148 
149   computeRegisterProperties(STI.getRegisterInfo());
150 }
151 
152 const MipsTargetLowering *
153 llvm::createMips16TargetLowering(const MipsTargetMachine &TM,
154                                  const MipsSubtarget &STI) {
155   return new Mips16TargetLowering(TM, STI);
156 }
157 
158 bool Mips16TargetLowering::allowsMisalignedMemoryAccesses(
159     EVT VT, unsigned, unsigned, MachineMemOperand::Flags, bool *Fast) const {
160   return false;
161 }
162 
163 MachineBasicBlock *
164 Mips16TargetLowering::EmitInstrWithCustomInserter(MachineInstr &MI,
165                                                   MachineBasicBlock *BB) const {
166   switch (MI.getOpcode()) {
167   default:
168     return MipsTargetLowering::EmitInstrWithCustomInserter(MI, BB);
169   case Mips::SelBeqZ:
170     return emitSel16(Mips::BeqzRxImm16, MI, BB);
171   case Mips::SelBneZ:
172     return emitSel16(Mips::BnezRxImm16, MI, BB);
173   case Mips::SelTBteqZCmpi:
174     return emitSeliT16(Mips::Bteqz16, Mips::CmpiRxImmX16, MI, BB);
175   case Mips::SelTBteqZSlti:
176     return emitSeliT16(Mips::Bteqz16, Mips::SltiRxImmX16, MI, BB);
177   case Mips::SelTBteqZSltiu:
178     return emitSeliT16(Mips::Bteqz16, Mips::SltiuRxImmX16, MI, BB);
179   case Mips::SelTBtneZCmpi:
180     return emitSeliT16(Mips::Btnez16, Mips::CmpiRxImmX16, MI, BB);
181   case Mips::SelTBtneZSlti:
182     return emitSeliT16(Mips::Btnez16, Mips::SltiRxImmX16, MI, BB);
183   case Mips::SelTBtneZSltiu:
184     return emitSeliT16(Mips::Btnez16, Mips::SltiuRxImmX16, MI, BB);
185   case Mips::SelTBteqZCmp:
186     return emitSelT16(Mips::Bteqz16, Mips::CmpRxRy16, MI, BB);
187   case Mips::SelTBteqZSlt:
188     return emitSelT16(Mips::Bteqz16, Mips::SltRxRy16, MI, BB);
189   case Mips::SelTBteqZSltu:
190     return emitSelT16(Mips::Bteqz16, Mips::SltuRxRy16, MI, BB);
191   case Mips::SelTBtneZCmp:
192     return emitSelT16(Mips::Btnez16, Mips::CmpRxRy16, MI, BB);
193   case Mips::SelTBtneZSlt:
194     return emitSelT16(Mips::Btnez16, Mips::SltRxRy16, MI, BB);
195   case Mips::SelTBtneZSltu:
196     return emitSelT16(Mips::Btnez16, Mips::SltuRxRy16, MI, BB);
197   case Mips::BteqzT8CmpX16:
198     return emitFEXT_T8I816_ins(Mips::Bteqz16, Mips::CmpRxRy16, MI, BB);
199   case Mips::BteqzT8SltX16:
200     return emitFEXT_T8I816_ins(Mips::Bteqz16, Mips::SltRxRy16, MI, BB);
201   case Mips::BteqzT8SltuX16:
202     // TBD: figure out a way to get this or remove the instruction
203     // altogether.
204     return emitFEXT_T8I816_ins(Mips::Bteqz16, Mips::SltuRxRy16, MI, BB);
205   case Mips::BtnezT8CmpX16:
206     return emitFEXT_T8I816_ins(Mips::Btnez16, Mips::CmpRxRy16, MI, BB);
207   case Mips::BtnezT8SltX16:
208     return emitFEXT_T8I816_ins(Mips::Btnez16, Mips::SltRxRy16, MI, BB);
209   case Mips::BtnezT8SltuX16:
210     // TBD: figure out a way to get this or remove the instruction
211     // altogether.
212     return emitFEXT_T8I816_ins(Mips::Btnez16, Mips::SltuRxRy16, MI, BB);
213   case Mips::BteqzT8CmpiX16: return emitFEXT_T8I8I16_ins(
214     Mips::Bteqz16, Mips::CmpiRxImm16, Mips::CmpiRxImmX16, false, MI, BB);
215   case Mips::BteqzT8SltiX16: return emitFEXT_T8I8I16_ins(
216     Mips::Bteqz16, Mips::SltiRxImm16, Mips::SltiRxImmX16, true, MI, BB);
217   case Mips::BteqzT8SltiuX16: return emitFEXT_T8I8I16_ins(
218     Mips::Bteqz16, Mips::SltiuRxImm16, Mips::SltiuRxImmX16, false, MI, BB);
219   case Mips::BtnezT8CmpiX16: return emitFEXT_T8I8I16_ins(
220     Mips::Btnez16, Mips::CmpiRxImm16, Mips::CmpiRxImmX16, false, MI, BB);
221   case Mips::BtnezT8SltiX16: return emitFEXT_T8I8I16_ins(
222     Mips::Btnez16, Mips::SltiRxImm16, Mips::SltiRxImmX16, true, MI, BB);
223   case Mips::BtnezT8SltiuX16: return emitFEXT_T8I8I16_ins(
224     Mips::Btnez16, Mips::SltiuRxImm16, Mips::SltiuRxImmX16, false, MI, BB);
225     break;
226   case Mips::SltCCRxRy16:
227     return emitFEXT_CCRX16_ins(Mips::SltRxRy16, MI, BB);
228     break;
229   case Mips::SltiCCRxImmX16:
230     return emitFEXT_CCRXI16_ins
231       (Mips::SltiRxImm16, Mips::SltiRxImmX16, MI, BB);
232   case Mips::SltiuCCRxImmX16:
233     return emitFEXT_CCRXI16_ins
234       (Mips::SltiuRxImm16, Mips::SltiuRxImmX16, MI, BB);
235   case Mips::SltuCCRxRy16:
236     return emitFEXT_CCRX16_ins
237       (Mips::SltuRxRy16, MI, BB);
238   }
239 }
240 
241 bool Mips16TargetLowering::isEligibleForTailCallOptimization(
242     const CCState &CCInfo, unsigned NextStackOffset,
243     const MipsFunctionInfo &FI) const {
244   // No tail call optimization for mips16.
245   return false;
246 }
247 
248 void Mips16TargetLowering::setMips16HardFloatLibCalls() {
249   for (unsigned I = 0; I != array_lengthof(HardFloatLibCalls); ++I) {
250     assert((I == 0 || HardFloatLibCalls[I - 1] < HardFloatLibCalls[I]) &&
251            "Array not sorted!");
252     if (HardFloatLibCalls[I].Libcall != RTLIB::UNKNOWN_LIBCALL)
253       setLibcallName(HardFloatLibCalls[I].Libcall, HardFloatLibCalls[I].Name);
254   }
255 
256   setLibcallName(RTLIB::O_F64, "__mips16_unorddf2");
257   setLibcallName(RTLIB::O_F32, "__mips16_unordsf2");
258 }
259 
260 //
261 // The Mips16 hard float is a crazy quilt inherited from gcc. I have a much
262 // cleaner way to do all of this but it will have to wait until the traditional
263 // gcc mechanism is completed.
264 //
265 // For Pic, in order for Mips16 code to call Mips32 code which according the abi
266 // have either arguments or returned values placed in floating point registers,
267 // we use a set of helper functions. (This includes functions which return type
268 //  complex which on Mips are returned in a pair of floating point registers).
269 //
270 // This is an encoding that we inherited from gcc.
271 // In Mips traditional O32, N32 ABI, floating point numbers are passed in
272 // floating point argument registers 1,2 only when the first and optionally
273 // the second arguments are float (sf) or double (df).
274 // For Mips16 we are only concerned with the situations where floating point
275 // arguments are being passed in floating point registers by the ABI, because
276 // Mips16 mode code cannot execute floating point instructions to load those
277 // values and hence helper functions are needed.
278 // The possibilities are (), (sf), (sf, sf), (sf, df), (df), (df, sf), (df, df)
279 // the helper function suffixs for these are:
280 //                        0,  1,    5,        9,         2,   6,        10
281 // this suffix can then be calculated as follows:
282 // for a given argument Arg:
283 //     Arg1x, Arg2x = 1 :  Arg is sf
284 //                    2 :  Arg is df
285 //                    0:   Arg is neither sf or df
286 // So this stub is the string for number Arg1x + Arg2x*4.
287 // However not all numbers between 0 and 10 are possible, we check anyway and
288 // assert if the impossible exists.
289 //
290 
291 unsigned int Mips16TargetLowering::getMips16HelperFunctionStubNumber
292   (ArgListTy &Args) const {
293   unsigned int resultNum = 0;
294   if (Args.size() >= 1) {
295     Type *t = Args[0].Ty;
296     if (t->isFloatTy()) {
297       resultNum = 1;
298     }
299     else if (t->isDoubleTy()) {
300       resultNum = 2;
301     }
302   }
303   if (resultNum) {
304     if (Args.size() >=2) {
305       Type *t = Args[1].Ty;
306       if (t->isFloatTy()) {
307         resultNum += 4;
308       }
309       else if (t->isDoubleTy()) {
310         resultNum += 8;
311       }
312     }
313   }
314   return resultNum;
315 }
316 
317 //
318 // Prefixes are attached to stub numbers depending on the return type.
319 // return type: float  sf_
320 //              double df_
321 //              single complex sc_
322 //              double complext dc_
323 //              others  NO PREFIX
324 //
325 //
326 // The full name of a helper function is__mips16_call_stub +
327 //    return type dependent prefix + stub number
328 //
329 // FIXME: This is something that probably should be in a different source file
330 // and perhaps done differently but my main purpose is to not waste runtime
331 // on something that we can enumerate in the source. Another possibility is
332 // to have a python script to generate these mapping tables. This will do
333 // for now. There are a whole series of helper function mapping arrays, one
334 // for each return type class as outlined above. There there are 11 possible
335 // entries. Ones with 0 are ones which should never be selected.
336 //
337 // All the arrays are similar except for ones which return neither
338 // sf, df, sc, dc, in which we only care about ones which have sf or df as a
339 // first parameter.
340 //
341 #define P_ "__mips16_call_stub_"
342 #define MAX_STUB_NUMBER 10
343 #define T1 P "1", P "2", 0, 0, P "5", P "6", 0, 0, P "9", P "10"
344 #define T P "0" , T1
345 #define P P_
346 static char const * vMips16Helper[MAX_STUB_NUMBER+1] =
347   {nullptr, T1 };
348 #undef P
349 #define P P_ "sf_"
350 static char const * sfMips16Helper[MAX_STUB_NUMBER+1] =
351   { T };
352 #undef P
353 #define P P_ "df_"
354 static char const * dfMips16Helper[MAX_STUB_NUMBER+1] =
355   { T };
356 #undef P
357 #define P P_ "sc_"
358 static char const * scMips16Helper[MAX_STUB_NUMBER+1] =
359   { T };
360 #undef P
361 #define P P_ "dc_"
362 static char const * dcMips16Helper[MAX_STUB_NUMBER+1] =
363   { T };
364 #undef P
365 #undef P_
366 
367 
368 const char* Mips16TargetLowering::
369   getMips16HelperFunction
370     (Type* RetTy, ArgListTy &Args, bool &needHelper) const {
371   const unsigned int stubNum = getMips16HelperFunctionStubNumber(Args);
372 #ifndef NDEBUG
373   const unsigned int maxStubNum = 10;
374   assert(stubNum <= maxStubNum);
375   const bool validStubNum[maxStubNum+1] =
376     {true, true, true, false, false, true, true, false, false, true, true};
377   assert(validStubNum[stubNum]);
378 #endif
379   const char *result;
380   if (RetTy->isFloatTy()) {
381     result = sfMips16Helper[stubNum];
382   }
383   else if (RetTy ->isDoubleTy()) {
384     result = dfMips16Helper[stubNum];
385   } else if (StructType *SRetTy = dyn_cast<StructType>(RetTy)) {
386     // check if it's complex
387     if (SRetTy->getNumElements() == 2) {
388       if ((SRetTy->getElementType(0)->isFloatTy()) &&
389           (SRetTy->getElementType(1)->isFloatTy())) {
390         result = scMips16Helper[stubNum];
391       } else if ((SRetTy->getElementType(0)->isDoubleTy()) &&
392                  (SRetTy->getElementType(1)->isDoubleTy())) {
393         result = dcMips16Helper[stubNum];
394       } else {
395         llvm_unreachable("Uncovered condition");
396       }
397     } else {
398       llvm_unreachable("Uncovered condition");
399     }
400   } else {
401     if (stubNum == 0) {
402       needHelper = false;
403       return "";
404     }
405     result = vMips16Helper[stubNum];
406   }
407   needHelper = true;
408   return result;
409 }
410 
411 void Mips16TargetLowering::
412 getOpndList(SmallVectorImpl<SDValue> &Ops,
413             std::deque< std::pair<unsigned, SDValue> > &RegsToPass,
414             bool IsPICCall, bool GlobalOrExternal, bool InternalLinkage,
415             bool IsCallReloc, CallLoweringInfo &CLI, SDValue Callee,
416             SDValue Chain) const {
417   SelectionDAG &DAG = CLI.DAG;
418   MachineFunction &MF = DAG.getMachineFunction();
419   MipsFunctionInfo *FuncInfo = MF.getInfo<MipsFunctionInfo>();
420   const char* Mips16HelperFunction = nullptr;
421   bool NeedMips16Helper = false;
422 
423   if (Subtarget.inMips16HardFloat()) {
424     //
425     // currently we don't have symbols tagged with the mips16 or mips32
426     // qualifier so we will assume that we don't know what kind it is.
427     // and generate the helper
428     //
429     bool LookupHelper = true;
430     if (ExternalSymbolSDNode *S = dyn_cast<ExternalSymbolSDNode>(CLI.Callee)) {
431       Mips16Libcall Find = { RTLIB::UNKNOWN_LIBCALL, S->getSymbol() };
432 
433       if (std::binary_search(std::begin(HardFloatLibCalls),
434                              std::end(HardFloatLibCalls), Find))
435         LookupHelper = false;
436       else {
437         const char *Symbol = S->getSymbol();
438         Mips16IntrinsicHelperType IntrinsicFind = { Symbol, "" };
439         const Mips16HardFloatInfo::FuncSignature *Signature =
440             Mips16HardFloatInfo::findFuncSignature(Symbol);
441         if (!IsPICCall && (Signature && (FuncInfo->StubsNeeded.find(Symbol) ==
442                                          FuncInfo->StubsNeeded.end()))) {
443           FuncInfo->StubsNeeded[Symbol] = Signature;
444           //
445           // S2 is normally saved if the stub is for a function which
446           // returns a float or double value and is not otherwise. This is
447           // because more work is required after the function the stub
448           // is calling completes, and so the stub cannot directly return
449           // and the stub has no stack space to store the return address so
450           // S2 is used for that purpose.
451           // In order to take advantage of not saving S2, we need to also
452           // optimize the call in the stub and this requires some further
453           // functionality in MipsAsmPrinter which we don't have yet.
454           // So for now we always save S2. The optimization will be done
455           // in a follow-on patch.
456           //
457           if (1 || (Signature->RetSig != Mips16HardFloatInfo::NoFPRet))
458             FuncInfo->setSaveS2();
459         }
460         // one more look at list of intrinsics
461         const Mips16IntrinsicHelperType *Helper =
462             llvm::lower_bound(Mips16IntrinsicHelper, IntrinsicFind);
463         if (Helper != std::end(Mips16IntrinsicHelper) &&
464             *Helper == IntrinsicFind) {
465           Mips16HelperFunction = Helper->Helper;
466           NeedMips16Helper = true;
467           LookupHelper = false;
468         }
469 
470       }
471     } else if (GlobalAddressSDNode *G =
472                    dyn_cast<GlobalAddressSDNode>(CLI.Callee)) {
473       Mips16Libcall Find = { RTLIB::UNKNOWN_LIBCALL,
474                              G->getGlobal()->getName().data() };
475 
476       if (std::binary_search(std::begin(HardFloatLibCalls),
477                              std::end(HardFloatLibCalls), Find))
478         LookupHelper = false;
479     }
480     if (LookupHelper)
481       Mips16HelperFunction =
482         getMips16HelperFunction(CLI.RetTy, CLI.getArgs(), NeedMips16Helper);
483   }
484 
485   SDValue JumpTarget = Callee;
486 
487   // T9 should contain the address of the callee function if
488   // -relocation-model=pic or it is an indirect call.
489   if (IsPICCall || !GlobalOrExternal) {
490     unsigned V0Reg = Mips::V0;
491     if (NeedMips16Helper) {
492       RegsToPass.push_front(std::make_pair(V0Reg, Callee));
493       JumpTarget = DAG.getExternalSymbol(Mips16HelperFunction,
494                                          getPointerTy(DAG.getDataLayout()));
495       ExternalSymbolSDNode *S = cast<ExternalSymbolSDNode>(JumpTarget);
496       JumpTarget = getAddrGlobal(S, CLI.DL, JumpTarget.getValueType(), DAG,
497                                  MipsII::MO_GOT, Chain,
498                                  FuncInfo->callPtrInfo(S->getSymbol()));
499     } else
500       RegsToPass.push_front(std::make_pair((unsigned)Mips::T9, Callee));
501   }
502 
503   Ops.push_back(JumpTarget);
504 
505   MipsTargetLowering::getOpndList(Ops, RegsToPass, IsPICCall, GlobalOrExternal,
506                                   InternalLinkage, IsCallReloc, CLI, Callee,
507                                   Chain);
508 }
509 
510 MachineBasicBlock *
511 Mips16TargetLowering::emitSel16(unsigned Opc, MachineInstr &MI,
512                                 MachineBasicBlock *BB) const {
513   if (DontExpandCondPseudos16)
514     return BB;
515   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
516   DebugLoc DL = MI.getDebugLoc();
517   // To "insert" a SELECT_CC instruction, we actually have to insert the
518   // diamond control-flow pattern.  The incoming instruction knows the
519   // destination vreg to set, the condition code register to branch on, the
520   // true/false values to select between, and a branch opcode to use.
521   const BasicBlock *LLVM_BB = BB->getBasicBlock();
522   MachineFunction::iterator It = ++BB->getIterator();
523 
524   //  thisMBB:
525   //  ...
526   //   TrueVal = ...
527   //   setcc r1, r2, r3
528   //   bNE   r1, r0, copy1MBB
529   //   fallthrough --> copy0MBB
530   MachineBasicBlock *thisMBB  = BB;
531   MachineFunction *F = BB->getParent();
532   MachineBasicBlock *copy0MBB = F->CreateMachineBasicBlock(LLVM_BB);
533   MachineBasicBlock *sinkMBB  = F->CreateMachineBasicBlock(LLVM_BB);
534   F->insert(It, copy0MBB);
535   F->insert(It, sinkMBB);
536 
537   // Transfer the remainder of BB and its successor edges to sinkMBB.
538   sinkMBB->splice(sinkMBB->begin(), BB,
539                   std::next(MachineBasicBlock::iterator(MI)), BB->end());
540   sinkMBB->transferSuccessorsAndUpdatePHIs(BB);
541 
542   // Next, add the true and fallthrough blocks as its successors.
543   BB->addSuccessor(copy0MBB);
544   BB->addSuccessor(sinkMBB);
545 
546   BuildMI(BB, DL, TII->get(Opc))
547       .addReg(MI.getOperand(3).getReg())
548       .addMBB(sinkMBB);
549 
550   //  copy0MBB:
551   //   %FalseValue = ...
552   //   # fallthrough to sinkMBB
553   BB = copy0MBB;
554 
555   // Update machine-CFG edges
556   BB->addSuccessor(sinkMBB);
557 
558   //  sinkMBB:
559   //   %Result = phi [ %TrueValue, thisMBB ], [ %FalseValue, copy0MBB ]
560   //  ...
561   BB = sinkMBB;
562 
563   BuildMI(*BB, BB->begin(), DL, TII->get(Mips::PHI), MI.getOperand(0).getReg())
564       .addReg(MI.getOperand(1).getReg())
565       .addMBB(thisMBB)
566       .addReg(MI.getOperand(2).getReg())
567       .addMBB(copy0MBB);
568 
569   MI.eraseFromParent(); // The pseudo instruction is gone now.
570   return BB;
571 }
572 
573 MachineBasicBlock *
574 Mips16TargetLowering::emitSelT16(unsigned Opc1, unsigned Opc2, MachineInstr &MI,
575                                  MachineBasicBlock *BB) const {
576   if (DontExpandCondPseudos16)
577     return BB;
578   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
579   DebugLoc DL = MI.getDebugLoc();
580   // To "insert" a SELECT_CC instruction, we actually have to insert the
581   // diamond control-flow pattern.  The incoming instruction knows the
582   // destination vreg to set, the condition code register to branch on, the
583   // true/false values to select between, and a branch opcode to use.
584   const BasicBlock *LLVM_BB = BB->getBasicBlock();
585   MachineFunction::iterator It = ++BB->getIterator();
586 
587   //  thisMBB:
588   //  ...
589   //   TrueVal = ...
590   //   setcc r1, r2, r3
591   //   bNE   r1, r0, copy1MBB
592   //   fallthrough --> copy0MBB
593   MachineBasicBlock *thisMBB  = BB;
594   MachineFunction *F = BB->getParent();
595   MachineBasicBlock *copy0MBB = F->CreateMachineBasicBlock(LLVM_BB);
596   MachineBasicBlock *sinkMBB  = F->CreateMachineBasicBlock(LLVM_BB);
597   F->insert(It, copy0MBB);
598   F->insert(It, sinkMBB);
599 
600   // Transfer the remainder of BB and its successor edges to sinkMBB.
601   sinkMBB->splice(sinkMBB->begin(), BB,
602                   std::next(MachineBasicBlock::iterator(MI)), BB->end());
603   sinkMBB->transferSuccessorsAndUpdatePHIs(BB);
604 
605   // Next, add the true and fallthrough blocks as its successors.
606   BB->addSuccessor(copy0MBB);
607   BB->addSuccessor(sinkMBB);
608 
609   BuildMI(BB, DL, TII->get(Opc2))
610       .addReg(MI.getOperand(3).getReg())
611       .addReg(MI.getOperand(4).getReg());
612   BuildMI(BB, DL, TII->get(Opc1)).addMBB(sinkMBB);
613 
614   //  copy0MBB:
615   //   %FalseValue = ...
616   //   # fallthrough to sinkMBB
617   BB = copy0MBB;
618 
619   // Update machine-CFG edges
620   BB->addSuccessor(sinkMBB);
621 
622   //  sinkMBB:
623   //   %Result = phi [ %TrueValue, thisMBB ], [ %FalseValue, copy0MBB ]
624   //  ...
625   BB = sinkMBB;
626 
627   BuildMI(*BB, BB->begin(), DL, TII->get(Mips::PHI), MI.getOperand(0).getReg())
628       .addReg(MI.getOperand(1).getReg())
629       .addMBB(thisMBB)
630       .addReg(MI.getOperand(2).getReg())
631       .addMBB(copy0MBB);
632 
633   MI.eraseFromParent(); // The pseudo instruction is gone now.
634   return BB;
635 
636 }
637 
638 MachineBasicBlock *
639 Mips16TargetLowering::emitSeliT16(unsigned Opc1, unsigned Opc2,
640                                   MachineInstr &MI,
641                                   MachineBasicBlock *BB) const {
642   if (DontExpandCondPseudos16)
643     return BB;
644   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
645   DebugLoc DL = MI.getDebugLoc();
646   // To "insert" a SELECT_CC instruction, we actually have to insert the
647   // diamond control-flow pattern.  The incoming instruction knows the
648   // destination vreg to set, the condition code register to branch on, the
649   // true/false values to select between, and a branch opcode to use.
650   const BasicBlock *LLVM_BB = BB->getBasicBlock();
651   MachineFunction::iterator It = ++BB->getIterator();
652 
653   //  thisMBB:
654   //  ...
655   //   TrueVal = ...
656   //   setcc r1, r2, r3
657   //   bNE   r1, r0, copy1MBB
658   //   fallthrough --> copy0MBB
659   MachineBasicBlock *thisMBB  = BB;
660   MachineFunction *F = BB->getParent();
661   MachineBasicBlock *copy0MBB = F->CreateMachineBasicBlock(LLVM_BB);
662   MachineBasicBlock *sinkMBB  = F->CreateMachineBasicBlock(LLVM_BB);
663   F->insert(It, copy0MBB);
664   F->insert(It, sinkMBB);
665 
666   // Transfer the remainder of BB and its successor edges to sinkMBB.
667   sinkMBB->splice(sinkMBB->begin(), BB,
668                   std::next(MachineBasicBlock::iterator(MI)), BB->end());
669   sinkMBB->transferSuccessorsAndUpdatePHIs(BB);
670 
671   // Next, add the true and fallthrough blocks as its successors.
672   BB->addSuccessor(copy0MBB);
673   BB->addSuccessor(sinkMBB);
674 
675   BuildMI(BB, DL, TII->get(Opc2))
676       .addReg(MI.getOperand(3).getReg())
677       .addImm(MI.getOperand(4).getImm());
678   BuildMI(BB, DL, TII->get(Opc1)).addMBB(sinkMBB);
679 
680   //  copy0MBB:
681   //   %FalseValue = ...
682   //   # fallthrough to sinkMBB
683   BB = copy0MBB;
684 
685   // Update machine-CFG edges
686   BB->addSuccessor(sinkMBB);
687 
688   //  sinkMBB:
689   //   %Result = phi [ %TrueValue, thisMBB ], [ %FalseValue, copy0MBB ]
690   //  ...
691   BB = sinkMBB;
692 
693   BuildMI(*BB, BB->begin(), DL, TII->get(Mips::PHI), MI.getOperand(0).getReg())
694       .addReg(MI.getOperand(1).getReg())
695       .addMBB(thisMBB)
696       .addReg(MI.getOperand(2).getReg())
697       .addMBB(copy0MBB);
698 
699   MI.eraseFromParent(); // The pseudo instruction is gone now.
700   return BB;
701 
702 }
703 
704 MachineBasicBlock *
705 Mips16TargetLowering::emitFEXT_T8I816_ins(unsigned BtOpc, unsigned CmpOpc,
706                                           MachineInstr &MI,
707                                           MachineBasicBlock *BB) const {
708   if (DontExpandCondPseudos16)
709     return BB;
710   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
711   Register regX = MI.getOperand(0).getReg();
712   Register regY = MI.getOperand(1).getReg();
713   MachineBasicBlock *target = MI.getOperand(2).getMBB();
714   BuildMI(*BB, MI, MI.getDebugLoc(), TII->get(CmpOpc))
715       .addReg(regX)
716       .addReg(regY);
717   BuildMI(*BB, MI, MI.getDebugLoc(), TII->get(BtOpc)).addMBB(target);
718   MI.eraseFromParent(); // The pseudo instruction is gone now.
719   return BB;
720 }
721 
722 MachineBasicBlock *Mips16TargetLowering::emitFEXT_T8I8I16_ins(
723     unsigned BtOpc, unsigned CmpiOpc, unsigned CmpiXOpc, bool ImmSigned,
724     MachineInstr &MI, MachineBasicBlock *BB) const {
725   if (DontExpandCondPseudos16)
726     return BB;
727   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
728   Register regX = MI.getOperand(0).getReg();
729   int64_t imm = MI.getOperand(1).getImm();
730   MachineBasicBlock *target = MI.getOperand(2).getMBB();
731   unsigned CmpOpc;
732   if (isUInt<8>(imm))
733     CmpOpc = CmpiOpc;
734   else if ((!ImmSigned && isUInt<16>(imm)) ||
735            (ImmSigned && isInt<16>(imm)))
736     CmpOpc = CmpiXOpc;
737   else
738     llvm_unreachable("immediate field not usable");
739   BuildMI(*BB, MI, MI.getDebugLoc(), TII->get(CmpOpc)).addReg(regX).addImm(imm);
740   BuildMI(*BB, MI, MI.getDebugLoc(), TII->get(BtOpc)).addMBB(target);
741   MI.eraseFromParent(); // The pseudo instruction is gone now.
742   return BB;
743 }
744 
745 static unsigned Mips16WhichOp8uOr16simm
746   (unsigned shortOp, unsigned longOp, int64_t Imm) {
747   if (isUInt<8>(Imm))
748     return shortOp;
749   else if (isInt<16>(Imm))
750     return longOp;
751   else
752     llvm_unreachable("immediate field not usable");
753 }
754 
755 MachineBasicBlock *
756 Mips16TargetLowering::emitFEXT_CCRX16_ins(unsigned SltOpc, MachineInstr &MI,
757                                           MachineBasicBlock *BB) const {
758   if (DontExpandCondPseudos16)
759     return BB;
760   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
761   Register CC = MI.getOperand(0).getReg();
762   Register regX = MI.getOperand(1).getReg();
763   Register regY = MI.getOperand(2).getReg();
764   BuildMI(*BB, MI, MI.getDebugLoc(), TII->get(SltOpc))
765       .addReg(regX)
766       .addReg(regY);
767   BuildMI(*BB, MI, MI.getDebugLoc(), TII->get(Mips::MoveR3216), CC)
768       .addReg(Mips::T8);
769   MI.eraseFromParent(); // The pseudo instruction is gone now.
770   return BB;
771 }
772 
773 MachineBasicBlock *
774 Mips16TargetLowering::emitFEXT_CCRXI16_ins(unsigned SltiOpc, unsigned SltiXOpc,
775                                            MachineInstr &MI,
776                                            MachineBasicBlock *BB) const {
777   if (DontExpandCondPseudos16)
778     return BB;
779   const TargetInstrInfo *TII = Subtarget.getInstrInfo();
780   Register CC = MI.getOperand(0).getReg();
781   Register regX = MI.getOperand(1).getReg();
782   int64_t Imm = MI.getOperand(2).getImm();
783   unsigned SltOpc = Mips16WhichOp8uOr16simm(SltiOpc, SltiXOpc, Imm);
784   BuildMI(*BB, MI, MI.getDebugLoc(), TII->get(SltOpc)).addReg(regX).addImm(Imm);
785   BuildMI(*BB, MI, MI.getDebugLoc(), TII->get(Mips::MoveR3216), CC)
786       .addReg(Mips::T8);
787   MI.eraseFromParent(); // The pseudo instruction is gone now.
788   return BB;
789 
790 }
791