1//===- AMDGPULibCalls.cpp -------------------------------------------------===//
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/// \file
10/// This file does AMD library function optimizations.
11//
12//===----------------------------------------------------------------------===//
13
14#include "AMDGPU.h"
15#include "AMDGPULibFunc.h"
16#include "GCNSubtarget.h"
17#include "llvm/Analysis/AssumptionCache.h"
18#include "llvm/Analysis/TargetLibraryInfo.h"
19#include "llvm/Analysis/ValueTracking.h"
20#include "llvm/IR/AttributeMask.h"
21#include "llvm/IR/Dominators.h"
22#include "llvm/IR/IRBuilder.h"
23#include "llvm/IR/IntrinsicInst.h"
24#include "llvm/IR/IntrinsicsAMDGPU.h"
25#include "llvm/IR/PatternMatch.h"
26#include "llvm/InitializePasses.h"
27#include <cmath>
28
29#define DEBUG_TYPE "amdgpu-simplifylib"
30
31using namespace llvm;
32using namespace llvm::PatternMatch;
33
34static cl::opt<bool> EnablePreLink("amdgpu-prelink",
35  cl::desc("Enable pre-link mode optimizations"),
36  cl::init(false),
37  cl::Hidden);
38
39static cl::list<std::string> UseNative("amdgpu-use-native",
40  cl::desc("Comma separated list of functions to replace with native, or all"),
41  cl::CommaSeparated, cl::ValueOptional,
42  cl::Hidden);
43
44#define MATH_PI      numbers::pi
45#define MATH_E       numbers::e
46#define MATH_SQRT2   numbers::sqrt2
47#define MATH_SQRT1_2 numbers::inv_sqrt2
48
49namespace llvm {
50
51class AMDGPULibCalls {
52private:
53  const TargetLibraryInfo *TLInfo = nullptr;
54  AssumptionCache *AC = nullptr;
55  DominatorTree *DT = nullptr;
56
57  typedef llvm::AMDGPULibFunc FuncInfo;
58
59  bool UnsafeFPMath = false;
60
61  // -fuse-native.
62  bool AllNative = false;
63
64  bool useNativeFunc(const StringRef F) const;
65
66  // Return a pointer (pointer expr) to the function if function definition with
67  // "FuncName" exists. It may create a new function prototype in pre-link mode.
68  FunctionCallee getFunction(Module *M, const FuncInfo &fInfo);
69
70  bool parseFunctionName(const StringRef &FMangledName, FuncInfo &FInfo);
71
72  bool TDOFold(CallInst *CI, const FuncInfo &FInfo);
73
74  /* Specialized optimizations */
75
76  // pow/powr/pown
77  bool fold_pow(FPMathOperator *FPOp, IRBuilder<> &B, const FuncInfo &FInfo);
78
79  // rootn
80  bool fold_rootn(FPMathOperator *FPOp, IRBuilder<> &B, const FuncInfo &FInfo);
81
82  // -fuse-native for sincos
83  bool sincosUseNative(CallInst *aCI, const FuncInfo &FInfo);
84
85  // evaluate calls if calls' arguments are constants.
86  bool evaluateScalarMathFunc(const FuncInfo &FInfo, double &Res0, double &Res1,
87                              Constant *copr0, Constant *copr1);
88  bool evaluateCall(CallInst *aCI, const FuncInfo &FInfo);
89
90  /// Insert a value to sincos function \p Fsincos. Returns (value of sin, value
91  /// of cos, sincos call).
92  std::tuple<Value *, Value *, Value *> insertSinCos(Value *Arg,
93                                                     FastMathFlags FMF,
94                                                     IRBuilder<> &B,
95                                                     FunctionCallee Fsincos);
96
97  // sin/cos
98  bool fold_sincos(FPMathOperator *FPOp, IRBuilder<> &B, const FuncInfo &FInfo);
99
100  // __read_pipe/__write_pipe
101  bool fold_read_write_pipe(CallInst *CI, IRBuilder<> &B,
102                            const FuncInfo &FInfo);
103
104  // Get a scalar native builtin single argument FP function
105  FunctionCallee getNativeFunction(Module *M, const FuncInfo &FInfo);
106
107  /// Substitute a call to a known libcall with an intrinsic call. If \p
108  /// AllowMinSize is true, allow the replacement in a minsize function.
109  bool shouldReplaceLibcallWithIntrinsic(const CallInst *CI,
110                                         bool AllowMinSizeF32 = false,
111                                         bool AllowF64 = false,
112                                         bool AllowStrictFP = false);
113  void replaceLibCallWithSimpleIntrinsic(IRBuilder<> &B, CallInst *CI,
114                                         Intrinsic::ID IntrID);
115
116  bool tryReplaceLibcallWithSimpleIntrinsic(IRBuilder<> &B, CallInst *CI,
117                                            Intrinsic::ID IntrID,
118                                            bool AllowMinSizeF32 = false,
119                                            bool AllowF64 = false,
120                                            bool AllowStrictFP = false);
121
122protected:
123  bool isUnsafeMath(const FPMathOperator *FPOp) const;
124  bool isUnsafeFiniteOnlyMath(const FPMathOperator *FPOp) const;
125
126  bool canIncreasePrecisionOfConstantFold(const FPMathOperator *FPOp) const;
127
128  static void replaceCall(Instruction *I, Value *With) {
129    I->replaceAllUsesWith(With);
130    I->eraseFromParent();
131  }
132
133  static void replaceCall(FPMathOperator *I, Value *With) {
134    replaceCall(cast<Instruction>(I), With);
135  }
136
137public:
138  AMDGPULibCalls() {}
139
140  bool fold(CallInst *CI);
141
142  void initFunction(Function &F, FunctionAnalysisManager &FAM);
143  void initNativeFuncs();
144
145  // Replace a normal math function call with that native version
146  bool useNative(CallInst *CI);
147};
148
149} // end llvm namespace
150
151template <typename IRB>
152static CallInst *CreateCallEx(IRB &B, FunctionCallee Callee, Value *Arg,
153                              const Twine &Name = "") {
154  CallInst *R = B.CreateCall(Callee, Arg, Name);
155  if (Function *F = dyn_cast<Function>(Callee.getCallee()))
156    R->setCallingConv(F->getCallingConv());
157  return R;
158}
159
160template <typename IRB>
161static CallInst *CreateCallEx2(IRB &B, FunctionCallee Callee, Value *Arg1,
162                               Value *Arg2, const Twine &Name = "") {
163  CallInst *R = B.CreateCall(Callee, {Arg1, Arg2}, Name);
164  if (Function *F = dyn_cast<Function>(Callee.getCallee()))
165    R->setCallingConv(F->getCallingConv());
166  return R;
167}
168
169static FunctionType *getPownType(FunctionType *FT) {
170  Type *PowNExpTy = Type::getInt32Ty(FT->getContext());
171  if (VectorType *VecTy = dyn_cast<VectorType>(FT->getReturnType()))
172    PowNExpTy = VectorType::get(PowNExpTy, VecTy->getElementCount());
173
174  return FunctionType::get(FT->getReturnType(),
175                           {FT->getParamType(0), PowNExpTy}, false);
176}
177
178//  Data structures for table-driven optimizations.
179//  FuncTbl works for both f32 and f64 functions with 1 input argument
180
181struct TableEntry {
182  double   result;
183  double   input;
184};
185
186/* a list of {result, input} */
187static const TableEntry tbl_acos[] = {
188  {MATH_PI / 2.0, 0.0},
189  {MATH_PI / 2.0, -0.0},
190  {0.0, 1.0},
191  {MATH_PI, -1.0}
192};
193static const TableEntry tbl_acosh[] = {
194  {0.0, 1.0}
195};
196static const TableEntry tbl_acospi[] = {
197  {0.5, 0.0},
198  {0.5, -0.0},
199  {0.0, 1.0},
200  {1.0, -1.0}
201};
202static const TableEntry tbl_asin[] = {
203  {0.0, 0.0},
204  {-0.0, -0.0},
205  {MATH_PI / 2.0, 1.0},
206  {-MATH_PI / 2.0, -1.0}
207};
208static const TableEntry tbl_asinh[] = {
209  {0.0, 0.0},
210  {-0.0, -0.0}
211};
212static const TableEntry tbl_asinpi[] = {
213  {0.0, 0.0},
214  {-0.0, -0.0},
215  {0.5, 1.0},
216  {-0.5, -1.0}
217};
218static const TableEntry tbl_atan[] = {
219  {0.0, 0.0},
220  {-0.0, -0.0},
221  {MATH_PI / 4.0, 1.0},
222  {-MATH_PI / 4.0, -1.0}
223};
224static const TableEntry tbl_atanh[] = {
225  {0.0, 0.0},
226  {-0.0, -0.0}
227};
228static const TableEntry tbl_atanpi[] = {
229  {0.0, 0.0},
230  {-0.0, -0.0},
231  {0.25, 1.0},
232  {-0.25, -1.0}
233};
234static const TableEntry tbl_cbrt[] = {
235  {0.0, 0.0},
236  {-0.0, -0.0},
237  {1.0, 1.0},
238  {-1.0, -1.0},
239};
240static const TableEntry tbl_cos[] = {
241  {1.0, 0.0},
242  {1.0, -0.0}
243};
244static const TableEntry tbl_cosh[] = {
245  {1.0, 0.0},
246  {1.0, -0.0}
247};
248static const TableEntry tbl_cospi[] = {
249  {1.0, 0.0},
250  {1.0, -0.0}
251};
252static const TableEntry tbl_erfc[] = {
253  {1.0, 0.0},
254  {1.0, -0.0}
255};
256static const TableEntry tbl_erf[] = {
257  {0.0, 0.0},
258  {-0.0, -0.0}
259};
260static const TableEntry tbl_exp[] = {
261  {1.0, 0.0},
262  {1.0, -0.0},
263  {MATH_E, 1.0}
264};
265static const TableEntry tbl_exp2[] = {
266  {1.0, 0.0},
267  {1.0, -0.0},
268  {2.0, 1.0}
269};
270static const TableEntry tbl_exp10[] = {
271  {1.0, 0.0},
272  {1.0, -0.0},
273  {10.0, 1.0}
274};
275static const TableEntry tbl_expm1[] = {
276  {0.0, 0.0},
277  {-0.0, -0.0}
278};
279static const TableEntry tbl_log[] = {
280  {0.0, 1.0},
281  {1.0, MATH_E}
282};
283static const TableEntry tbl_log2[] = {
284  {0.0, 1.0},
285  {1.0, 2.0}
286};
287static const TableEntry tbl_log10[] = {
288  {0.0, 1.0},
289  {1.0, 10.0}
290};
291static const TableEntry tbl_rsqrt[] = {
292  {1.0, 1.0},
293  {MATH_SQRT1_2, 2.0}
294};
295static const TableEntry tbl_sin[] = {
296  {0.0, 0.0},
297  {-0.0, -0.0}
298};
299static const TableEntry tbl_sinh[] = {
300  {0.0, 0.0},
301  {-0.0, -0.0}
302};
303static const TableEntry tbl_sinpi[] = {
304  {0.0, 0.0},
305  {-0.0, -0.0}
306};
307static const TableEntry tbl_sqrt[] = {
308  {0.0, 0.0},
309  {1.0, 1.0},
310  {MATH_SQRT2, 2.0}
311};
312static const TableEntry tbl_tan[] = {
313  {0.0, 0.0},
314  {-0.0, -0.0}
315};
316static const TableEntry tbl_tanh[] = {
317  {0.0, 0.0},
318  {-0.0, -0.0}
319};
320static const TableEntry tbl_tanpi[] = {
321  {0.0, 0.0},
322  {-0.0, -0.0}
323};
324static const TableEntry tbl_tgamma[] = {
325  {1.0, 1.0},
326  {1.0, 2.0},
327  {2.0, 3.0},
328  {6.0, 4.0}
329};
330
331static bool HasNative(AMDGPULibFunc::EFuncId id) {
332  switch(id) {
333  case AMDGPULibFunc::EI_DIVIDE:
334  case AMDGPULibFunc::EI_COS:
335  case AMDGPULibFunc::EI_EXP:
336  case AMDGPULibFunc::EI_EXP2:
337  case AMDGPULibFunc::EI_EXP10:
338  case AMDGPULibFunc::EI_LOG:
339  case AMDGPULibFunc::EI_LOG2:
340  case AMDGPULibFunc::EI_LOG10:
341  case AMDGPULibFunc::EI_POWR:
342  case AMDGPULibFunc::EI_RECIP:
343  case AMDGPULibFunc::EI_RSQRT:
344  case AMDGPULibFunc::EI_SIN:
345  case AMDGPULibFunc::EI_SINCOS:
346  case AMDGPULibFunc::EI_SQRT:
347  case AMDGPULibFunc::EI_TAN:
348    return true;
349  default:;
350  }
351  return false;
352}
353
354using TableRef = ArrayRef<TableEntry>;
355
356static TableRef getOptTable(AMDGPULibFunc::EFuncId id) {
357  switch(id) {
358  case AMDGPULibFunc::EI_ACOS:    return TableRef(tbl_acos);
359  case AMDGPULibFunc::EI_ACOSH:   return TableRef(tbl_acosh);
360  case AMDGPULibFunc::EI_ACOSPI:  return TableRef(tbl_acospi);
361  case AMDGPULibFunc::EI_ASIN:    return TableRef(tbl_asin);
362  case AMDGPULibFunc::EI_ASINH:   return TableRef(tbl_asinh);
363  case AMDGPULibFunc::EI_ASINPI:  return TableRef(tbl_asinpi);
364  case AMDGPULibFunc::EI_ATAN:    return TableRef(tbl_atan);
365  case AMDGPULibFunc::EI_ATANH:   return TableRef(tbl_atanh);
366  case AMDGPULibFunc::EI_ATANPI:  return TableRef(tbl_atanpi);
367  case AMDGPULibFunc::EI_CBRT:    return TableRef(tbl_cbrt);
368  case AMDGPULibFunc::EI_NCOS:
369  case AMDGPULibFunc::EI_COS:     return TableRef(tbl_cos);
370  case AMDGPULibFunc::EI_COSH:    return TableRef(tbl_cosh);
371  case AMDGPULibFunc::EI_COSPI:   return TableRef(tbl_cospi);
372  case AMDGPULibFunc::EI_ERFC:    return TableRef(tbl_erfc);
373  case AMDGPULibFunc::EI_ERF:     return TableRef(tbl_erf);
374  case AMDGPULibFunc::EI_EXP:     return TableRef(tbl_exp);
375  case AMDGPULibFunc::EI_NEXP2:
376  case AMDGPULibFunc::EI_EXP2:    return TableRef(tbl_exp2);
377  case AMDGPULibFunc::EI_EXP10:   return TableRef(tbl_exp10);
378  case AMDGPULibFunc::EI_EXPM1:   return TableRef(tbl_expm1);
379  case AMDGPULibFunc::EI_LOG:     return TableRef(tbl_log);
380  case AMDGPULibFunc::EI_NLOG2:
381  case AMDGPULibFunc::EI_LOG2:    return TableRef(tbl_log2);
382  case AMDGPULibFunc::EI_LOG10:   return TableRef(tbl_log10);
383  case AMDGPULibFunc::EI_NRSQRT:
384  case AMDGPULibFunc::EI_RSQRT:   return TableRef(tbl_rsqrt);
385  case AMDGPULibFunc::EI_NSIN:
386  case AMDGPULibFunc::EI_SIN:     return TableRef(tbl_sin);
387  case AMDGPULibFunc::EI_SINH:    return TableRef(tbl_sinh);
388  case AMDGPULibFunc::EI_SINPI:   return TableRef(tbl_sinpi);
389  case AMDGPULibFunc::EI_NSQRT:
390  case AMDGPULibFunc::EI_SQRT:    return TableRef(tbl_sqrt);
391  case AMDGPULibFunc::EI_TAN:     return TableRef(tbl_tan);
392  case AMDGPULibFunc::EI_TANH:    return TableRef(tbl_tanh);
393  case AMDGPULibFunc::EI_TANPI:   return TableRef(tbl_tanpi);
394  case AMDGPULibFunc::EI_TGAMMA:  return TableRef(tbl_tgamma);
395  default:;
396  }
397  return TableRef();
398}
399
400static inline int getVecSize(const AMDGPULibFunc& FInfo) {
401  return FInfo.getLeads()[0].VectorSize;
402}
403
404static inline AMDGPULibFunc::EType getArgType(const AMDGPULibFunc& FInfo) {
405  return (AMDGPULibFunc::EType)FInfo.getLeads()[0].ArgType;
406}
407
408FunctionCallee AMDGPULibCalls::getFunction(Module *M, const FuncInfo &fInfo) {
409  // If we are doing PreLinkOpt, the function is external. So it is safe to
410  // use getOrInsertFunction() at this stage.
411
412  return EnablePreLink ? AMDGPULibFunc::getOrInsertFunction(M, fInfo)
413                       : AMDGPULibFunc::getFunction(M, fInfo);
414}
415
416bool AMDGPULibCalls::parseFunctionName(const StringRef &FMangledName,
417                                       FuncInfo &FInfo) {
418  return AMDGPULibFunc::parse(FMangledName, FInfo);
419}
420
421bool AMDGPULibCalls::isUnsafeMath(const FPMathOperator *FPOp) const {
422  return UnsafeFPMath || FPOp->isFast();
423}
424
425bool AMDGPULibCalls::isUnsafeFiniteOnlyMath(const FPMathOperator *FPOp) const {
426  return UnsafeFPMath ||
427         (FPOp->hasApproxFunc() && FPOp->hasNoNaNs() && FPOp->hasNoInfs());
428}
429
430bool AMDGPULibCalls::canIncreasePrecisionOfConstantFold(
431    const FPMathOperator *FPOp) const {
432  // TODO: Refine to approxFunc or contract
433  return isUnsafeMath(FPOp);
434}
435
436void AMDGPULibCalls::initFunction(Function &F, FunctionAnalysisManager &FAM) {
437  UnsafeFPMath = F.getFnAttribute("unsafe-fp-math").getValueAsBool();
438  AC = &FAM.getResult<AssumptionAnalysis>(F);
439  TLInfo = &FAM.getResult<TargetLibraryAnalysis>(F);
440  DT = FAM.getCachedResult<DominatorTreeAnalysis>(F);
441}
442
443bool AMDGPULibCalls::useNativeFunc(const StringRef F) const {
444  return AllNative || llvm::is_contained(UseNative, F);
445}
446
447void AMDGPULibCalls::initNativeFuncs() {
448  AllNative = useNativeFunc("all") ||
449              (UseNative.getNumOccurrences() && UseNative.size() == 1 &&
450               UseNative.begin()->empty());
451}
452
453bool AMDGPULibCalls::sincosUseNative(CallInst *aCI, const FuncInfo &FInfo) {
454  bool native_sin = useNativeFunc("sin");
455  bool native_cos = useNativeFunc("cos");
456
457  if (native_sin && native_cos) {
458    Module *M = aCI->getModule();
459    Value *opr0 = aCI->getArgOperand(0);
460
461    AMDGPULibFunc nf;
462    nf.getLeads()[0].ArgType = FInfo.getLeads()[0].ArgType;
463    nf.getLeads()[0].VectorSize = FInfo.getLeads()[0].VectorSize;
464
465    nf.setPrefix(AMDGPULibFunc::NATIVE);
466    nf.setId(AMDGPULibFunc::EI_SIN);
467    FunctionCallee sinExpr = getFunction(M, nf);
468
469    nf.setPrefix(AMDGPULibFunc::NATIVE);
470    nf.setId(AMDGPULibFunc::EI_COS);
471    FunctionCallee cosExpr = getFunction(M, nf);
472    if (sinExpr && cosExpr) {
473      Value *sinval = CallInst::Create(sinExpr, opr0, "splitsin", aCI);
474      Value *cosval = CallInst::Create(cosExpr, opr0, "splitcos", aCI);
475      new StoreInst(cosval, aCI->getArgOperand(1), aCI);
476
477      DEBUG_WITH_TYPE("usenative", dbgs() << "<useNative> replace " << *aCI
478                                          << " with native version of sin/cos");
479
480      replaceCall(aCI, sinval);
481      return true;
482    }
483  }
484  return false;
485}
486
487bool AMDGPULibCalls::useNative(CallInst *aCI) {
488  Function *Callee = aCI->getCalledFunction();
489  if (!Callee || aCI->isNoBuiltin())
490    return false;
491
492  FuncInfo FInfo;
493  if (!parseFunctionName(Callee->getName(), FInfo) || !FInfo.isMangled() ||
494      FInfo.getPrefix() != AMDGPULibFunc::NOPFX ||
495      getArgType(FInfo) == AMDGPULibFunc::F64 || !HasNative(FInfo.getId()) ||
496      !(AllNative || useNativeFunc(FInfo.getName()))) {
497    return false;
498  }
499
500  if (FInfo.getId() == AMDGPULibFunc::EI_SINCOS)
501    return sincosUseNative(aCI, FInfo);
502
503  FInfo.setPrefix(AMDGPULibFunc::NATIVE);
504  FunctionCallee F = getFunction(aCI->getModule(), FInfo);
505  if (!F)
506    return false;
507
508  aCI->setCalledFunction(F);
509  DEBUG_WITH_TYPE("usenative", dbgs() << "<useNative> replace " << *aCI
510                                      << " with native version");
511  return true;
512}
513
514// Clang emits call of __read_pipe_2 or __read_pipe_4 for OpenCL read_pipe
515// builtin, with appended type size and alignment arguments, where 2 or 4
516// indicates the original number of arguments. The library has optimized version
517// of __read_pipe_2/__read_pipe_4 when the type size and alignment has the same
518// power of 2 value. This function transforms __read_pipe_2 to __read_pipe_2_N
519// for such cases where N is the size in bytes of the type (N = 1, 2, 4, 8, ...,
520// 128). The same for __read_pipe_4, write_pipe_2, and write_pipe_4.
521bool AMDGPULibCalls::fold_read_write_pipe(CallInst *CI, IRBuilder<> &B,
522                                          const FuncInfo &FInfo) {
523  auto *Callee = CI->getCalledFunction();
524  if (!Callee->isDeclaration())
525    return false;
526
527  assert(Callee->hasName() && "Invalid read_pipe/write_pipe function");
528  auto *M = Callee->getParent();
529  std::string Name = std::string(Callee->getName());
530  auto NumArg = CI->arg_size();
531  if (NumArg != 4 && NumArg != 6)
532    return false;
533  ConstantInt *PacketSize =
534      dyn_cast<ConstantInt>(CI->getArgOperand(NumArg - 2));
535  ConstantInt *PacketAlign =
536      dyn_cast<ConstantInt>(CI->getArgOperand(NumArg - 1));
537  if (!PacketSize || !PacketAlign)
538    return false;
539
540  unsigned Size = PacketSize->getZExtValue();
541  Align Alignment = PacketAlign->getAlignValue();
542  if (Alignment != Size)
543    return false;
544
545  unsigned PtrArgLoc = CI->arg_size() - 3;
546  Value *PtrArg = CI->getArgOperand(PtrArgLoc);
547  Type *PtrTy = PtrArg->getType();
548
549  SmallVector<llvm::Type *, 6> ArgTys;
550  for (unsigned I = 0; I != PtrArgLoc; ++I)
551    ArgTys.push_back(CI->getArgOperand(I)->getType());
552  ArgTys.push_back(PtrTy);
553
554  Name = Name + "_" + std::to_string(Size);
555  auto *FTy = FunctionType::get(Callee->getReturnType(),
556                                ArrayRef<Type *>(ArgTys), false);
557  AMDGPULibFunc NewLibFunc(Name, FTy);
558  FunctionCallee F = AMDGPULibFunc::getOrInsertFunction(M, NewLibFunc);
559  if (!F)
560    return false;
561
562  SmallVector<Value *, 6> Args;
563  for (unsigned I = 0; I != PtrArgLoc; ++I)
564    Args.push_back(CI->getArgOperand(I));
565  Args.push_back(PtrArg);
566
567  auto *NCI = B.CreateCall(F, Args);
568  NCI->setAttributes(CI->getAttributes());
569  CI->replaceAllUsesWith(NCI);
570  CI->dropAllReferences();
571  CI->eraseFromParent();
572
573  return true;
574}
575
576static bool isKnownIntegral(const Value *V, const DataLayout &DL,
577                            FastMathFlags FMF) {
578  if (isa<UndefValue>(V))
579    return true;
580
581  if (const ConstantFP *CF = dyn_cast<ConstantFP>(V))
582    return CF->getValueAPF().isInteger();
583
584  if (const ConstantDataVector *CDV = dyn_cast<ConstantDataVector>(V)) {
585    for (unsigned i = 0, e = CDV->getNumElements(); i != e; ++i) {
586      Constant *ConstElt = CDV->getElementAsConstant(i);
587      if (isa<UndefValue>(ConstElt))
588        continue;
589      const ConstantFP *CFP = dyn_cast<ConstantFP>(ConstElt);
590      if (!CFP || !CFP->getValue().isInteger())
591        return false;
592    }
593
594    return true;
595  }
596
597  const Instruction *I = dyn_cast<Instruction>(V);
598  if (!I)
599    return false;
600
601  switch (I->getOpcode()) {
602  case Instruction::SIToFP:
603  case Instruction::UIToFP:
604    // TODO: Could check nofpclass(inf) on incoming argument
605    if (FMF.noInfs())
606      return true;
607
608    // Need to check int size cannot produce infinity, which computeKnownFPClass
609    // knows how to do already.
610    return isKnownNeverInfinity(I, DL);
611  case Instruction::Call: {
612    const CallInst *CI = cast<CallInst>(I);
613    switch (CI->getIntrinsicID()) {
614    case Intrinsic::trunc:
615    case Intrinsic::floor:
616    case Intrinsic::ceil:
617    case Intrinsic::rint:
618    case Intrinsic::nearbyint:
619    case Intrinsic::round:
620    case Intrinsic::roundeven:
621      return (FMF.noInfs() && FMF.noNaNs()) ||
622             isKnownNeverInfOrNaN(I, DL, nullptr);
623    default:
624      break;
625    }
626
627    break;
628  }
629  default:
630    break;
631  }
632
633  return false;
634}
635
636// This function returns false if no change; return true otherwise.
637bool AMDGPULibCalls::fold(CallInst *CI) {
638  Function *Callee = CI->getCalledFunction();
639  // Ignore indirect calls.
640  if (!Callee || Callee->isIntrinsic() || CI->isNoBuiltin())
641    return false;
642
643  FuncInfo FInfo;
644  if (!parseFunctionName(Callee->getName(), FInfo))
645    return false;
646
647  // Further check the number of arguments to see if they match.
648  // TODO: Check calling convention matches too
649  if (!FInfo.isCompatibleSignature(CI->getFunctionType()))
650    return false;
651
652  LLVM_DEBUG(dbgs() << "AMDIC: try folding " << *CI << '\n');
653
654  if (TDOFold(CI, FInfo))
655    return true;
656
657  IRBuilder<> B(CI);
658
659  if (FPMathOperator *FPOp = dyn_cast<FPMathOperator>(CI)) {
660    // Under unsafe-math, evaluate calls if possible.
661    // According to Brian Sumner, we can do this for all f32 function calls
662    // using host's double function calls.
663    if (canIncreasePrecisionOfConstantFold(FPOp) && evaluateCall(CI, FInfo))
664      return true;
665
666    // Copy fast flags from the original call.
667    FastMathFlags FMF = FPOp->getFastMathFlags();
668    B.setFastMathFlags(FMF);
669
670    // Specialized optimizations for each function call.
671    //
672    // TODO: Handle native functions
673    switch (FInfo.getId()) {
674    case AMDGPULibFunc::EI_EXP:
675      if (FMF.none())
676        return false;
677      return tryReplaceLibcallWithSimpleIntrinsic(B, CI, Intrinsic::exp,
678                                                  FMF.approxFunc());
679    case AMDGPULibFunc::EI_EXP2:
680      if (FMF.none())
681        return false;
682      return tryReplaceLibcallWithSimpleIntrinsic(B, CI, Intrinsic::exp2,
683                                                  FMF.approxFunc());
684    case AMDGPULibFunc::EI_LOG:
685      if (FMF.none())
686        return false;
687      return tryReplaceLibcallWithSimpleIntrinsic(B, CI, Intrinsic::log,
688                                                  FMF.approxFunc());
689    case AMDGPULibFunc::EI_LOG2:
690      if (FMF.none())
691        return false;
692      return tryReplaceLibcallWithSimpleIntrinsic(B, CI, Intrinsic::log2,
693                                                  FMF.approxFunc());
694    case AMDGPULibFunc::EI_LOG10:
695      if (FMF.none())
696        return false;
697      return tryReplaceLibcallWithSimpleIntrinsic(B, CI, Intrinsic::log10,
698                                                  FMF.approxFunc());
699    case AMDGPULibFunc::EI_FMIN:
700      return tryReplaceLibcallWithSimpleIntrinsic(B, CI, Intrinsic::minnum,
701                                                  true, true);
702    case AMDGPULibFunc::EI_FMAX:
703      return tryReplaceLibcallWithSimpleIntrinsic(B, CI, Intrinsic::maxnum,
704                                                  true, true);
705    case AMDGPULibFunc::EI_FMA:
706      return tryReplaceLibcallWithSimpleIntrinsic(B, CI, Intrinsic::fma, true,
707                                                  true);
708    case AMDGPULibFunc::EI_MAD:
709      return tryReplaceLibcallWithSimpleIntrinsic(B, CI, Intrinsic::fmuladd,
710                                                  true, true);
711    case AMDGPULibFunc::EI_FABS:
712      return tryReplaceLibcallWithSimpleIntrinsic(B, CI, Intrinsic::fabs, true,
713                                                  true, true);
714    case AMDGPULibFunc::EI_COPYSIGN:
715      return tryReplaceLibcallWithSimpleIntrinsic(B, CI, Intrinsic::copysign,
716                                                  true, true, true);
717    case AMDGPULibFunc::EI_FLOOR:
718      return tryReplaceLibcallWithSimpleIntrinsic(B, CI, Intrinsic::floor, true,
719                                                  true);
720    case AMDGPULibFunc::EI_CEIL:
721      return tryReplaceLibcallWithSimpleIntrinsic(B, CI, Intrinsic::ceil, true,
722                                                  true);
723    case AMDGPULibFunc::EI_TRUNC:
724      return tryReplaceLibcallWithSimpleIntrinsic(B, CI, Intrinsic::trunc, true,
725                                                  true);
726    case AMDGPULibFunc::EI_RINT:
727      return tryReplaceLibcallWithSimpleIntrinsic(B, CI, Intrinsic::rint, true,
728                                                  true);
729    case AMDGPULibFunc::EI_ROUND:
730      return tryReplaceLibcallWithSimpleIntrinsic(B, CI, Intrinsic::round, true,
731                                                  true);
732    case AMDGPULibFunc::EI_LDEXP: {
733      if (!shouldReplaceLibcallWithIntrinsic(CI, true, true))
734        return false;
735
736      Value *Arg1 = CI->getArgOperand(1);
737      if (VectorType *VecTy = dyn_cast<VectorType>(CI->getType());
738          VecTy && !isa<VectorType>(Arg1->getType())) {
739        Value *SplatArg1 = B.CreateVectorSplat(VecTy->getElementCount(), Arg1);
740        CI->setArgOperand(1, SplatArg1);
741      }
742
743      CI->setCalledFunction(Intrinsic::getDeclaration(
744          CI->getModule(), Intrinsic::ldexp,
745          {CI->getType(), CI->getArgOperand(1)->getType()}));
746      return true;
747    }
748    case AMDGPULibFunc::EI_POW: {
749      Module *M = Callee->getParent();
750      AMDGPULibFunc PowrInfo(AMDGPULibFunc::EI_POWR, FInfo);
751      FunctionCallee PowrFunc = getFunction(M, PowrInfo);
752      CallInst *Call = cast<CallInst>(FPOp);
753
754      // pow(x, y) -> powr(x, y) for x >= -0.0
755      // TODO: Account for flags on current call
756      if (PowrFunc &&
757          cannotBeOrderedLessThanZero(FPOp->getOperand(0), M->getDataLayout(),
758                                      TLInfo, 0, AC, Call, DT)) {
759        Call->setCalledFunction(PowrFunc);
760        return fold_pow(FPOp, B, PowrInfo) || true;
761      }
762
763      // pow(x, y) -> pown(x, y) for known integral y
764      if (isKnownIntegral(FPOp->getOperand(1), M->getDataLayout(),
765                          FPOp->getFastMathFlags())) {
766        FunctionType *PownType = getPownType(CI->getFunctionType());
767        AMDGPULibFunc PownInfo(AMDGPULibFunc::EI_POWN, PownType, true);
768        FunctionCallee PownFunc = getFunction(M, PownInfo);
769        if (PownFunc) {
770          // TODO: If the incoming integral value is an sitofp/uitofp, it won't
771          // fold out without a known range. We can probably take the source
772          // value directly.
773          Value *CastedArg =
774              B.CreateFPToSI(FPOp->getOperand(1), PownType->getParamType(1));
775          // Have to drop any nofpclass attributes on the original call site.
776          Call->removeParamAttrs(
777              1, AttributeFuncs::typeIncompatible(CastedArg->getType()));
778          Call->setCalledFunction(PownFunc);
779          Call->setArgOperand(1, CastedArg);
780          return fold_pow(FPOp, B, PownInfo) || true;
781        }
782      }
783
784      return fold_pow(FPOp, B, FInfo);
785    }
786    case AMDGPULibFunc::EI_POWR:
787    case AMDGPULibFunc::EI_POWN:
788      return fold_pow(FPOp, B, FInfo);
789    case AMDGPULibFunc::EI_ROOTN:
790      return fold_rootn(FPOp, B, FInfo);
791    case AMDGPULibFunc::EI_SQRT:
792      // TODO: Allow with strictfp + constrained intrinsic
793      return tryReplaceLibcallWithSimpleIntrinsic(
794          B, CI, Intrinsic::sqrt, true, true, /*AllowStrictFP=*/false);
795    case AMDGPULibFunc::EI_COS:
796    case AMDGPULibFunc::EI_SIN:
797      return fold_sincos(FPOp, B, FInfo);
798    default:
799      break;
800    }
801  } else {
802    // Specialized optimizations for each function call
803    switch (FInfo.getId()) {
804    case AMDGPULibFunc::EI_READ_PIPE_2:
805    case AMDGPULibFunc::EI_READ_PIPE_4:
806    case AMDGPULibFunc::EI_WRITE_PIPE_2:
807    case AMDGPULibFunc::EI_WRITE_PIPE_4:
808      return fold_read_write_pipe(CI, B, FInfo);
809    default:
810      break;
811    }
812  }
813
814  return false;
815}
816
817bool AMDGPULibCalls::TDOFold(CallInst *CI, const FuncInfo &FInfo) {
818  // Table-Driven optimization
819  const TableRef tr = getOptTable(FInfo.getId());
820  if (tr.empty())
821    return false;
822
823  int const sz = (int)tr.size();
824  Value *opr0 = CI->getArgOperand(0);
825
826  if (getVecSize(FInfo) > 1) {
827    if (ConstantDataVector *CV = dyn_cast<ConstantDataVector>(opr0)) {
828      SmallVector<double, 0> DVal;
829      for (int eltNo = 0; eltNo < getVecSize(FInfo); ++eltNo) {
830        ConstantFP *eltval = dyn_cast<ConstantFP>(
831                               CV->getElementAsConstant((unsigned)eltNo));
832        assert(eltval && "Non-FP arguments in math function!");
833        bool found = false;
834        for (int i=0; i < sz; ++i) {
835          if (eltval->isExactlyValue(tr[i].input)) {
836            DVal.push_back(tr[i].result);
837            found = true;
838            break;
839          }
840        }
841        if (!found) {
842          // This vector constants not handled yet.
843          return false;
844        }
845      }
846      LLVMContext &context = CI->getParent()->getParent()->getContext();
847      Constant *nval;
848      if (getArgType(FInfo) == AMDGPULibFunc::F32) {
849        SmallVector<float, 0> FVal;
850        for (unsigned i = 0; i < DVal.size(); ++i) {
851          FVal.push_back((float)DVal[i]);
852        }
853        ArrayRef<float> tmp(FVal);
854        nval = ConstantDataVector::get(context, tmp);
855      } else { // F64
856        ArrayRef<double> tmp(DVal);
857        nval = ConstantDataVector::get(context, tmp);
858      }
859      LLVM_DEBUG(errs() << "AMDIC: " << *CI << " ---> " << *nval << "\n");
860      replaceCall(CI, nval);
861      return true;
862    }
863  } else {
864    // Scalar version
865    if (ConstantFP *CF = dyn_cast<ConstantFP>(opr0)) {
866      for (int i = 0; i < sz; ++i) {
867        if (CF->isExactlyValue(tr[i].input)) {
868          Value *nval = ConstantFP::get(CF->getType(), tr[i].result);
869          LLVM_DEBUG(errs() << "AMDIC: " << *CI << " ---> " << *nval << "\n");
870          replaceCall(CI, nval);
871          return true;
872        }
873      }
874    }
875  }
876
877  return false;
878}
879
880namespace llvm {
881static double log2(double V) {
882#if _XOPEN_SOURCE >= 600 || defined(_ISOC99_SOURCE) || _POSIX_C_SOURCE >= 200112L
883  return ::log2(V);
884#else
885  return log(V) / numbers::ln2;
886#endif
887}
888}
889
890bool AMDGPULibCalls::fold_pow(FPMathOperator *FPOp, IRBuilder<> &B,
891                              const FuncInfo &FInfo) {
892  assert((FInfo.getId() == AMDGPULibFunc::EI_POW ||
893          FInfo.getId() == AMDGPULibFunc::EI_POWR ||
894          FInfo.getId() == AMDGPULibFunc::EI_POWN) &&
895         "fold_pow: encounter a wrong function call");
896
897  Module *M = B.GetInsertBlock()->getModule();
898  Type *eltType = FPOp->getType()->getScalarType();
899  Value *opr0 = FPOp->getOperand(0);
900  Value *opr1 = FPOp->getOperand(1);
901
902  const APFloat *CF = nullptr;
903  const APInt *CINT = nullptr;
904  if (!match(opr1, m_APFloatAllowUndef(CF)))
905    match(opr1, m_APIntAllowUndef(CINT));
906
907  // 0x1111111 means that we don't do anything for this call.
908  int ci_opr1 = (CINT ? (int)CINT->getSExtValue() : 0x1111111);
909
910  if ((CF && CF->isZero()) || (CINT && ci_opr1 == 0)) {
911    //  pow/powr/pown(x, 0) == 1
912    LLVM_DEBUG(errs() << "AMDIC: " << *FPOp << " ---> 1\n");
913    Constant *cnval = ConstantFP::get(eltType, 1.0);
914    if (getVecSize(FInfo) > 1) {
915      cnval = ConstantDataVector::getSplat(getVecSize(FInfo), cnval);
916    }
917    replaceCall(FPOp, cnval);
918    return true;
919  }
920  if ((CF && CF->isExactlyValue(1.0)) || (CINT && ci_opr1 == 1)) {
921    // pow/powr/pown(x, 1.0) = x
922    LLVM_DEBUG(errs() << "AMDIC: " << *FPOp << " ---> " << *opr0 << "\n");
923    replaceCall(FPOp, opr0);
924    return true;
925  }
926  if ((CF && CF->isExactlyValue(2.0)) || (CINT && ci_opr1 == 2)) {
927    // pow/powr/pown(x, 2.0) = x*x
928    LLVM_DEBUG(errs() << "AMDIC: " << *FPOp << " ---> " << *opr0 << " * "
929                      << *opr0 << "\n");
930    Value *nval = B.CreateFMul(opr0, opr0, "__pow2");
931    replaceCall(FPOp, nval);
932    return true;
933  }
934  if ((CF && CF->isExactlyValue(-1.0)) || (CINT && ci_opr1 == -1)) {
935    // pow/powr/pown(x, -1.0) = 1.0/x
936    LLVM_DEBUG(errs() << "AMDIC: " << *FPOp << " ---> 1 / " << *opr0 << "\n");
937    Constant *cnval = ConstantFP::get(eltType, 1.0);
938    if (getVecSize(FInfo) > 1) {
939      cnval = ConstantDataVector::getSplat(getVecSize(FInfo), cnval);
940    }
941    Value *nval = B.CreateFDiv(cnval, opr0, "__powrecip");
942    replaceCall(FPOp, nval);
943    return true;
944  }
945
946  if (CF && (CF->isExactlyValue(0.5) || CF->isExactlyValue(-0.5))) {
947    // pow[r](x, [-]0.5) = sqrt(x)
948    bool issqrt = CF->isExactlyValue(0.5);
949    if (FunctionCallee FPExpr =
950            getFunction(M, AMDGPULibFunc(issqrt ? AMDGPULibFunc::EI_SQRT
951                                                : AMDGPULibFunc::EI_RSQRT,
952                                         FInfo))) {
953      LLVM_DEBUG(errs() << "AMDIC: " << *FPOp << " ---> " << FInfo.getName()
954                        << '(' << *opr0 << ")\n");
955      Value *nval = CreateCallEx(B,FPExpr, opr0, issqrt ? "__pow2sqrt"
956                                                        : "__pow2rsqrt");
957      replaceCall(FPOp, nval);
958      return true;
959    }
960  }
961
962  if (!isUnsafeFiniteOnlyMath(FPOp))
963    return false;
964
965  // Unsafe Math optimization
966
967  // Remember that ci_opr1 is set if opr1 is integral
968  if (CF) {
969    double dval = (getArgType(FInfo) == AMDGPULibFunc::F32)
970                      ? (double)CF->convertToFloat()
971                      : CF->convertToDouble();
972    int ival = (int)dval;
973    if ((double)ival == dval) {
974      ci_opr1 = ival;
975    } else
976      ci_opr1 = 0x11111111;
977  }
978
979  // pow/powr/pown(x, c) = [1/](x*x*..x); where
980  //   trunc(c) == c && the number of x == c && |c| <= 12
981  unsigned abs_opr1 = (ci_opr1 < 0) ? -ci_opr1 : ci_opr1;
982  if (abs_opr1 <= 12) {
983    Constant *cnval;
984    Value *nval;
985    if (abs_opr1 == 0) {
986      cnval = ConstantFP::get(eltType, 1.0);
987      if (getVecSize(FInfo) > 1) {
988        cnval = ConstantDataVector::getSplat(getVecSize(FInfo), cnval);
989      }
990      nval = cnval;
991    } else {
992      Value *valx2 = nullptr;
993      nval = nullptr;
994      while (abs_opr1 > 0) {
995        valx2 = valx2 ? B.CreateFMul(valx2, valx2, "__powx2") : opr0;
996        if (abs_opr1 & 1) {
997          nval = nval ? B.CreateFMul(nval, valx2, "__powprod") : valx2;
998        }
999        abs_opr1 >>= 1;
1000      }
1001    }
1002
1003    if (ci_opr1 < 0) {
1004      cnval = ConstantFP::get(eltType, 1.0);
1005      if (getVecSize(FInfo) > 1) {
1006        cnval = ConstantDataVector::getSplat(getVecSize(FInfo), cnval);
1007      }
1008      nval = B.CreateFDiv(cnval, nval, "__1powprod");
1009    }
1010    LLVM_DEBUG(errs() << "AMDIC: " << *FPOp << " ---> "
1011                      << ((ci_opr1 < 0) ? "1/prod(" : "prod(") << *opr0
1012                      << ")\n");
1013    replaceCall(FPOp, nval);
1014    return true;
1015  }
1016
1017  // If we should use the generic intrinsic instead of emitting a libcall
1018  const bool ShouldUseIntrinsic = eltType->isFloatTy() || eltType->isHalfTy();
1019
1020  // powr ---> exp2(y * log2(x))
1021  // pown/pow ---> powr(fabs(x), y) | (x & ((int)y << 31))
1022  FunctionCallee ExpExpr;
1023  if (ShouldUseIntrinsic)
1024    ExpExpr = Intrinsic::getDeclaration(M, Intrinsic::exp2, {FPOp->getType()});
1025  else {
1026    ExpExpr = getFunction(M, AMDGPULibFunc(AMDGPULibFunc::EI_EXP2, FInfo));
1027    if (!ExpExpr)
1028      return false;
1029  }
1030
1031  bool needlog = false;
1032  bool needabs = false;
1033  bool needcopysign = false;
1034  Constant *cnval = nullptr;
1035  if (getVecSize(FInfo) == 1) {
1036    CF = nullptr;
1037    match(opr0, m_APFloatAllowUndef(CF));
1038
1039    if (CF) {
1040      double V = (getArgType(FInfo) == AMDGPULibFunc::F32)
1041                     ? (double)CF->convertToFloat()
1042                     : CF->convertToDouble();
1043
1044      V = log2(std::abs(V));
1045      cnval = ConstantFP::get(eltType, V);
1046      needcopysign = (FInfo.getId() != AMDGPULibFunc::EI_POWR) &&
1047                     CF->isNegative();
1048    } else {
1049      needlog = true;
1050      needcopysign = needabs = FInfo.getId() != AMDGPULibFunc::EI_POWR;
1051    }
1052  } else {
1053    ConstantDataVector *CDV = dyn_cast<ConstantDataVector>(opr0);
1054
1055    if (!CDV) {
1056      needlog = true;
1057      needcopysign = needabs = FInfo.getId() != AMDGPULibFunc::EI_POWR;
1058    } else {
1059      assert ((int)CDV->getNumElements() == getVecSize(FInfo) &&
1060              "Wrong vector size detected");
1061
1062      SmallVector<double, 0> DVal;
1063      for (int i=0; i < getVecSize(FInfo); ++i) {
1064        double V = CDV->getElementAsAPFloat(i).convertToDouble();
1065        if (V < 0.0) needcopysign = true;
1066        V = log2(std::abs(V));
1067        DVal.push_back(V);
1068      }
1069      if (getArgType(FInfo) == AMDGPULibFunc::F32) {
1070        SmallVector<float, 0> FVal;
1071        for (unsigned i=0; i < DVal.size(); ++i) {
1072          FVal.push_back((float)DVal[i]);
1073        }
1074        ArrayRef<float> tmp(FVal);
1075        cnval = ConstantDataVector::get(M->getContext(), tmp);
1076      } else {
1077        ArrayRef<double> tmp(DVal);
1078        cnval = ConstantDataVector::get(M->getContext(), tmp);
1079      }
1080    }
1081  }
1082
1083  if (needcopysign && (FInfo.getId() == AMDGPULibFunc::EI_POW)) {
1084    // We cannot handle corner cases for a general pow() function, give up
1085    // unless y is a constant integral value. Then proceed as if it were pown.
1086    if (!isKnownIntegral(opr1, M->getDataLayout(), FPOp->getFastMathFlags()))
1087      return false;
1088  }
1089
1090  Value *nval;
1091  if (needabs) {
1092    nval = B.CreateUnaryIntrinsic(Intrinsic::fabs, opr0, nullptr, "__fabs");
1093  } else {
1094    nval = cnval ? cnval : opr0;
1095  }
1096  if (needlog) {
1097    FunctionCallee LogExpr;
1098    if (ShouldUseIntrinsic) {
1099      LogExpr =
1100          Intrinsic::getDeclaration(M, Intrinsic::log2, {FPOp->getType()});
1101    } else {
1102      LogExpr = getFunction(M, AMDGPULibFunc(AMDGPULibFunc::EI_LOG2, FInfo));
1103      if (!LogExpr)
1104        return false;
1105    }
1106
1107    nval = CreateCallEx(B,LogExpr, nval, "__log2");
1108  }
1109
1110  if (FInfo.getId() == AMDGPULibFunc::EI_POWN) {
1111    // convert int(32) to fp(f32 or f64)
1112    opr1 = B.CreateSIToFP(opr1, nval->getType(), "pownI2F");
1113  }
1114  nval = B.CreateFMul(opr1, nval, "__ylogx");
1115  nval = CreateCallEx(B,ExpExpr, nval, "__exp2");
1116
1117  if (needcopysign) {
1118    Value *opr_n;
1119    Type* rTy = opr0->getType();
1120    Type* nTyS = B.getIntNTy(eltType->getPrimitiveSizeInBits());
1121    Type *nTy = nTyS;
1122    if (const auto *vTy = dyn_cast<FixedVectorType>(rTy))
1123      nTy = FixedVectorType::get(nTyS, vTy);
1124    unsigned size = nTy->getScalarSizeInBits();
1125    opr_n = FPOp->getOperand(1);
1126    if (opr_n->getType()->isIntegerTy())
1127      opr_n = B.CreateZExtOrTrunc(opr_n, nTy, "__ytou");
1128    else
1129      opr_n = B.CreateFPToSI(opr1, nTy, "__ytou");
1130
1131    Value *sign = B.CreateShl(opr_n, size-1, "__yeven");
1132    sign = B.CreateAnd(B.CreateBitCast(opr0, nTy), sign, "__pow_sign");
1133    nval = B.CreateOr(B.CreateBitCast(nval, nTy), sign);
1134    nval = B.CreateBitCast(nval, opr0->getType());
1135  }
1136
1137  LLVM_DEBUG(errs() << "AMDIC: " << *FPOp << " ---> "
1138                    << "exp2(" << *opr1 << " * log2(" << *opr0 << "))\n");
1139  replaceCall(FPOp, nval);
1140
1141  return true;
1142}
1143
1144bool AMDGPULibCalls::fold_rootn(FPMathOperator *FPOp, IRBuilder<> &B,
1145                                const FuncInfo &FInfo) {
1146  // skip vector function
1147  if (getVecSize(FInfo) != 1)
1148    return false;
1149
1150  Value *opr0 = FPOp->getOperand(0);
1151  Value *opr1 = FPOp->getOperand(1);
1152
1153  ConstantInt *CINT = dyn_cast<ConstantInt>(opr1);
1154  if (!CINT) {
1155    return false;
1156  }
1157  int ci_opr1 = (int)CINT->getSExtValue();
1158  if (ci_opr1 == 1) {  // rootn(x, 1) = x
1159    LLVM_DEBUG(errs() << "AMDIC: " << *FPOp << " ---> " << *opr0 << "\n");
1160    replaceCall(FPOp, opr0);
1161    return true;
1162  }
1163
1164  Module *M = B.GetInsertBlock()->getModule();
1165  if (ci_opr1 == 2) { // rootn(x, 2) = sqrt(x)
1166    if (FunctionCallee FPExpr =
1167            getFunction(M, AMDGPULibFunc(AMDGPULibFunc::EI_SQRT, FInfo))) {
1168      LLVM_DEBUG(errs() << "AMDIC: " << *FPOp << " ---> sqrt(" << *opr0
1169                        << ")\n");
1170      Value *nval = CreateCallEx(B,FPExpr, opr0, "__rootn2sqrt");
1171      replaceCall(FPOp, nval);
1172      return true;
1173    }
1174  } else if (ci_opr1 == 3) { // rootn(x, 3) = cbrt(x)
1175    if (FunctionCallee FPExpr =
1176            getFunction(M, AMDGPULibFunc(AMDGPULibFunc::EI_CBRT, FInfo))) {
1177      LLVM_DEBUG(errs() << "AMDIC: " << *FPOp << " ---> cbrt(" << *opr0
1178                        << ")\n");
1179      Value *nval = CreateCallEx(B,FPExpr, opr0, "__rootn2cbrt");
1180      replaceCall(FPOp, nval);
1181      return true;
1182    }
1183  } else if (ci_opr1 == -1) { // rootn(x, -1) = 1.0/x
1184    LLVM_DEBUG(errs() << "AMDIC: " << *FPOp << " ---> 1.0 / " << *opr0 << "\n");
1185    Value *nval = B.CreateFDiv(ConstantFP::get(opr0->getType(), 1.0),
1186                               opr0,
1187                               "__rootn2div");
1188    replaceCall(FPOp, nval);
1189    return true;
1190  } else if (ci_opr1 == -2) { // rootn(x, -2) = rsqrt(x)
1191    if (FunctionCallee FPExpr =
1192            getFunction(M, AMDGPULibFunc(AMDGPULibFunc::EI_RSQRT, FInfo))) {
1193      LLVM_DEBUG(errs() << "AMDIC: " << *FPOp << " ---> rsqrt(" << *opr0
1194                        << ")\n");
1195      Value *nval = CreateCallEx(B,FPExpr, opr0, "__rootn2rsqrt");
1196      replaceCall(FPOp, nval);
1197      return true;
1198    }
1199  }
1200  return false;
1201}
1202
1203// Get a scalar native builtin single argument FP function
1204FunctionCallee AMDGPULibCalls::getNativeFunction(Module *M,
1205                                                 const FuncInfo &FInfo) {
1206  if (getArgType(FInfo) == AMDGPULibFunc::F64 || !HasNative(FInfo.getId()))
1207    return nullptr;
1208  FuncInfo nf = FInfo;
1209  nf.setPrefix(AMDGPULibFunc::NATIVE);
1210  return getFunction(M, nf);
1211}
1212
1213// Some library calls are just wrappers around llvm intrinsics, but compiled
1214// conservatively. Preserve the flags from the original call site by
1215// substituting them with direct calls with all the flags.
1216bool AMDGPULibCalls::shouldReplaceLibcallWithIntrinsic(const CallInst *CI,
1217                                                       bool AllowMinSizeF32,
1218                                                       bool AllowF64,
1219                                                       bool AllowStrictFP) {
1220  Type *FltTy = CI->getType()->getScalarType();
1221  const bool IsF32 = FltTy->isFloatTy();
1222
1223  // f64 intrinsics aren't implemented for most operations.
1224  if (!IsF32 && !FltTy->isHalfTy() && (!AllowF64 || !FltTy->isDoubleTy()))
1225    return false;
1226
1227  // We're implicitly inlining by replacing the libcall with the intrinsic, so
1228  // don't do it for noinline call sites.
1229  if (CI->isNoInline())
1230    return false;
1231
1232  const Function *ParentF = CI->getFunction();
1233  // TODO: Handle strictfp
1234  if (!AllowStrictFP && ParentF->hasFnAttribute(Attribute::StrictFP))
1235    return false;
1236
1237  if (IsF32 && !AllowMinSizeF32 && ParentF->hasMinSize())
1238    return false;
1239  return true;
1240}
1241
1242void AMDGPULibCalls::replaceLibCallWithSimpleIntrinsic(IRBuilder<> &B,
1243                                                       CallInst *CI,
1244                                                       Intrinsic::ID IntrID) {
1245  if (CI->arg_size() == 2) {
1246    Value *Arg0 = CI->getArgOperand(0);
1247    Value *Arg1 = CI->getArgOperand(1);
1248    VectorType *Arg0VecTy = dyn_cast<VectorType>(Arg0->getType());
1249    VectorType *Arg1VecTy = dyn_cast<VectorType>(Arg1->getType());
1250    if (Arg0VecTy && !Arg1VecTy) {
1251      Value *SplatRHS = B.CreateVectorSplat(Arg0VecTy->getElementCount(), Arg1);
1252      CI->setArgOperand(1, SplatRHS);
1253    } else if (!Arg0VecTy && Arg1VecTy) {
1254      Value *SplatLHS = B.CreateVectorSplat(Arg1VecTy->getElementCount(), Arg0);
1255      CI->setArgOperand(0, SplatLHS);
1256    }
1257  }
1258
1259  CI->setCalledFunction(
1260      Intrinsic::getDeclaration(CI->getModule(), IntrID, {CI->getType()}));
1261}
1262
1263bool AMDGPULibCalls::tryReplaceLibcallWithSimpleIntrinsic(
1264    IRBuilder<> &B, CallInst *CI, Intrinsic::ID IntrID, bool AllowMinSizeF32,
1265    bool AllowF64, bool AllowStrictFP) {
1266  if (!shouldReplaceLibcallWithIntrinsic(CI, AllowMinSizeF32, AllowF64,
1267                                         AllowStrictFP))
1268    return false;
1269  replaceLibCallWithSimpleIntrinsic(B, CI, IntrID);
1270  return true;
1271}
1272
1273std::tuple<Value *, Value *, Value *>
1274AMDGPULibCalls::insertSinCos(Value *Arg, FastMathFlags FMF, IRBuilder<> &B,
1275                             FunctionCallee Fsincos) {
1276  DebugLoc DL = B.getCurrentDebugLocation();
1277  Function *F = B.GetInsertBlock()->getParent();
1278  B.SetInsertPointPastAllocas(F);
1279
1280  AllocaInst *Alloc = B.CreateAlloca(Arg->getType(), nullptr, "__sincos_");
1281
1282  if (Instruction *ArgInst = dyn_cast<Instruction>(Arg)) {
1283    // If the argument is an instruction, it must dominate all uses so put our
1284    // sincos call there. Otherwise, right after the allocas works well enough
1285    // if it's an argument or constant.
1286
1287    B.SetInsertPoint(ArgInst->getParent(), ++ArgInst->getIterator());
1288
1289    // SetInsertPoint unwelcomely always tries to set the debug loc.
1290    B.SetCurrentDebugLocation(DL);
1291  }
1292
1293  Type *CosPtrTy = Fsincos.getFunctionType()->getParamType(1);
1294
1295  // The allocaInst allocates the memory in private address space. This need
1296  // to be addrspacecasted to point to the address space of cos pointer type.
1297  // In OpenCL 2.0 this is generic, while in 1.2 that is private.
1298  Value *CastAlloc = B.CreateAddrSpaceCast(Alloc, CosPtrTy);
1299
1300  CallInst *SinCos = CreateCallEx2(B, Fsincos, Arg, CastAlloc);
1301
1302  // TODO: Is it worth trying to preserve the location for the cos calls for the
1303  // load?
1304
1305  LoadInst *LoadCos = B.CreateLoad(Alloc->getAllocatedType(), Alloc);
1306  return {SinCos, LoadCos, SinCos};
1307}
1308
1309// fold sin, cos -> sincos.
1310bool AMDGPULibCalls::fold_sincos(FPMathOperator *FPOp, IRBuilder<> &B,
1311                                 const FuncInfo &fInfo) {
1312  assert(fInfo.getId() == AMDGPULibFunc::EI_SIN ||
1313         fInfo.getId() == AMDGPULibFunc::EI_COS);
1314
1315  if ((getArgType(fInfo) != AMDGPULibFunc::F32 &&
1316       getArgType(fInfo) != AMDGPULibFunc::F64) ||
1317      fInfo.getPrefix() != AMDGPULibFunc::NOPFX)
1318    return false;
1319
1320  bool const isSin = fInfo.getId() == AMDGPULibFunc::EI_SIN;
1321
1322  Value *CArgVal = FPOp->getOperand(0);
1323  CallInst *CI = cast<CallInst>(FPOp);
1324
1325  Function *F = B.GetInsertBlock()->getParent();
1326  Module *M = F->getParent();
1327
1328  // Merge the sin and cos. For OpenCL 2.0, there may only be a generic pointer
1329  // implementation. Prefer the private form if available.
1330  AMDGPULibFunc SinCosLibFuncPrivate(AMDGPULibFunc::EI_SINCOS, fInfo);
1331  SinCosLibFuncPrivate.getLeads()[0].PtrKind =
1332      AMDGPULibFunc::getEPtrKindFromAddrSpace(AMDGPUAS::PRIVATE_ADDRESS);
1333
1334  AMDGPULibFunc SinCosLibFuncGeneric(AMDGPULibFunc::EI_SINCOS, fInfo);
1335  SinCosLibFuncGeneric.getLeads()[0].PtrKind =
1336      AMDGPULibFunc::getEPtrKindFromAddrSpace(AMDGPUAS::FLAT_ADDRESS);
1337
1338  FunctionCallee FSinCosPrivate = getFunction(M, SinCosLibFuncPrivate);
1339  FunctionCallee FSinCosGeneric = getFunction(M, SinCosLibFuncGeneric);
1340  FunctionCallee FSinCos = FSinCosPrivate ? FSinCosPrivate : FSinCosGeneric;
1341  if (!FSinCos)
1342    return false;
1343
1344  SmallVector<CallInst *> SinCalls;
1345  SmallVector<CallInst *> CosCalls;
1346  SmallVector<CallInst *> SinCosCalls;
1347  FuncInfo PartnerInfo(isSin ? AMDGPULibFunc::EI_COS : AMDGPULibFunc::EI_SIN,
1348                       fInfo);
1349  const std::string PairName = PartnerInfo.mangle();
1350
1351  StringRef SinName = isSin ? CI->getCalledFunction()->getName() : PairName;
1352  StringRef CosName = isSin ? PairName : CI->getCalledFunction()->getName();
1353  const std::string SinCosPrivateName = SinCosLibFuncPrivate.mangle();
1354  const std::string SinCosGenericName = SinCosLibFuncGeneric.mangle();
1355
1356  // Intersect the two sets of flags.
1357  FastMathFlags FMF = FPOp->getFastMathFlags();
1358  MDNode *FPMath = CI->getMetadata(LLVMContext::MD_fpmath);
1359
1360  SmallVector<DILocation *> MergeDbgLocs = {CI->getDebugLoc()};
1361
1362  for (User* U : CArgVal->users()) {
1363    CallInst *XI = dyn_cast<CallInst>(U);
1364    if (!XI || XI->getFunction() != F || XI->isNoBuiltin())
1365      continue;
1366
1367    Function *UCallee = XI->getCalledFunction();
1368    if (!UCallee)
1369      continue;
1370
1371    bool Handled = true;
1372
1373    if (UCallee->getName() == SinName)
1374      SinCalls.push_back(XI);
1375    else if (UCallee->getName() == CosName)
1376      CosCalls.push_back(XI);
1377    else if (UCallee->getName() == SinCosPrivateName ||
1378             UCallee->getName() == SinCosGenericName)
1379      SinCosCalls.push_back(XI);
1380    else
1381      Handled = false;
1382
1383    if (Handled) {
1384      MergeDbgLocs.push_back(XI->getDebugLoc());
1385      auto *OtherOp = cast<FPMathOperator>(XI);
1386      FMF &= OtherOp->getFastMathFlags();
1387      FPMath = MDNode::getMostGenericFPMath(
1388          FPMath, XI->getMetadata(LLVMContext::MD_fpmath));
1389    }
1390  }
1391
1392  if (SinCalls.empty() || CosCalls.empty())
1393    return false;
1394
1395  B.setFastMathFlags(FMF);
1396  B.setDefaultFPMathTag(FPMath);
1397  DILocation *DbgLoc = DILocation::getMergedLocations(MergeDbgLocs);
1398  B.SetCurrentDebugLocation(DbgLoc);
1399
1400  auto [Sin, Cos, SinCos] = insertSinCos(CArgVal, FMF, B, FSinCos);
1401
1402  auto replaceTrigInsts = [](ArrayRef<CallInst *> Calls, Value *Res) {
1403    for (CallInst *C : Calls)
1404      C->replaceAllUsesWith(Res);
1405
1406    // Leave the other dead instructions to avoid clobbering iterators.
1407  };
1408
1409  replaceTrigInsts(SinCalls, Sin);
1410  replaceTrigInsts(CosCalls, Cos);
1411  replaceTrigInsts(SinCosCalls, SinCos);
1412
1413  // It's safe to delete the original now.
1414  CI->eraseFromParent();
1415  return true;
1416}
1417
1418bool AMDGPULibCalls::evaluateScalarMathFunc(const FuncInfo &FInfo, double &Res0,
1419                                            double &Res1, Constant *copr0,
1420                                            Constant *copr1) {
1421  // By default, opr0/opr1/opr3 holds values of float/double type.
1422  // If they are not float/double, each function has to its
1423  // operand separately.
1424  double opr0 = 0.0, opr1 = 0.0;
1425  ConstantFP *fpopr0 = dyn_cast_or_null<ConstantFP>(copr0);
1426  ConstantFP *fpopr1 = dyn_cast_or_null<ConstantFP>(copr1);
1427  if (fpopr0) {
1428    opr0 = (getArgType(FInfo) == AMDGPULibFunc::F64)
1429             ? fpopr0->getValueAPF().convertToDouble()
1430             : (double)fpopr0->getValueAPF().convertToFloat();
1431  }
1432
1433  if (fpopr1) {
1434    opr1 = (getArgType(FInfo) == AMDGPULibFunc::F64)
1435             ? fpopr1->getValueAPF().convertToDouble()
1436             : (double)fpopr1->getValueAPF().convertToFloat();
1437  }
1438
1439  switch (FInfo.getId()) {
1440  default : return false;
1441
1442  case AMDGPULibFunc::EI_ACOS:
1443    Res0 = acos(opr0);
1444    return true;
1445
1446  case AMDGPULibFunc::EI_ACOSH:
1447    // acosh(x) == log(x + sqrt(x*x - 1))
1448    Res0 = log(opr0 + sqrt(opr0*opr0 - 1.0));
1449    return true;
1450
1451  case AMDGPULibFunc::EI_ACOSPI:
1452    Res0 = acos(opr0) / MATH_PI;
1453    return true;
1454
1455  case AMDGPULibFunc::EI_ASIN:
1456    Res0 = asin(opr0);
1457    return true;
1458
1459  case AMDGPULibFunc::EI_ASINH:
1460    // asinh(x) == log(x + sqrt(x*x + 1))
1461    Res0 = log(opr0 + sqrt(opr0*opr0 + 1.0));
1462    return true;
1463
1464  case AMDGPULibFunc::EI_ASINPI:
1465    Res0 = asin(opr0) / MATH_PI;
1466    return true;
1467
1468  case AMDGPULibFunc::EI_ATAN:
1469    Res0 = atan(opr0);
1470    return true;
1471
1472  case AMDGPULibFunc::EI_ATANH:
1473    // atanh(x) == (log(x+1) - log(x-1))/2;
1474    Res0 = (log(opr0 + 1.0) - log(opr0 - 1.0))/2.0;
1475    return true;
1476
1477  case AMDGPULibFunc::EI_ATANPI:
1478    Res0 = atan(opr0) / MATH_PI;
1479    return true;
1480
1481  case AMDGPULibFunc::EI_CBRT:
1482    Res0 = (opr0 < 0.0) ? -pow(-opr0, 1.0/3.0) : pow(opr0, 1.0/3.0);
1483    return true;
1484
1485  case AMDGPULibFunc::EI_COS:
1486    Res0 = cos(opr0);
1487    return true;
1488
1489  case AMDGPULibFunc::EI_COSH:
1490    Res0 = cosh(opr0);
1491    return true;
1492
1493  case AMDGPULibFunc::EI_COSPI:
1494    Res0 = cos(MATH_PI * opr0);
1495    return true;
1496
1497  case AMDGPULibFunc::EI_EXP:
1498    Res0 = exp(opr0);
1499    return true;
1500
1501  case AMDGPULibFunc::EI_EXP2:
1502    Res0 = pow(2.0, opr0);
1503    return true;
1504
1505  case AMDGPULibFunc::EI_EXP10:
1506    Res0 = pow(10.0, opr0);
1507    return true;
1508
1509  case AMDGPULibFunc::EI_LOG:
1510    Res0 = log(opr0);
1511    return true;
1512
1513  case AMDGPULibFunc::EI_LOG2:
1514    Res0 = log(opr0) / log(2.0);
1515    return true;
1516
1517  case AMDGPULibFunc::EI_LOG10:
1518    Res0 = log(opr0) / log(10.0);
1519    return true;
1520
1521  case AMDGPULibFunc::EI_RSQRT:
1522    Res0 = 1.0 / sqrt(opr0);
1523    return true;
1524
1525  case AMDGPULibFunc::EI_SIN:
1526    Res0 = sin(opr0);
1527    return true;
1528
1529  case AMDGPULibFunc::EI_SINH:
1530    Res0 = sinh(opr0);
1531    return true;
1532
1533  case AMDGPULibFunc::EI_SINPI:
1534    Res0 = sin(MATH_PI * opr0);
1535    return true;
1536
1537  case AMDGPULibFunc::EI_TAN:
1538    Res0 = tan(opr0);
1539    return true;
1540
1541  case AMDGPULibFunc::EI_TANH:
1542    Res0 = tanh(opr0);
1543    return true;
1544
1545  case AMDGPULibFunc::EI_TANPI:
1546    Res0 = tan(MATH_PI * opr0);
1547    return true;
1548
1549  // two-arg functions
1550  case AMDGPULibFunc::EI_POW:
1551  case AMDGPULibFunc::EI_POWR:
1552    Res0 = pow(opr0, opr1);
1553    return true;
1554
1555  case AMDGPULibFunc::EI_POWN: {
1556    if (ConstantInt *iopr1 = dyn_cast_or_null<ConstantInt>(copr1)) {
1557      double val = (double)iopr1->getSExtValue();
1558      Res0 = pow(opr0, val);
1559      return true;
1560    }
1561    return false;
1562  }
1563
1564  case AMDGPULibFunc::EI_ROOTN: {
1565    if (ConstantInt *iopr1 = dyn_cast_or_null<ConstantInt>(copr1)) {
1566      double val = (double)iopr1->getSExtValue();
1567      Res0 = pow(opr0, 1.0 / val);
1568      return true;
1569    }
1570    return false;
1571  }
1572
1573  // with ptr arg
1574  case AMDGPULibFunc::EI_SINCOS:
1575    Res0 = sin(opr0);
1576    Res1 = cos(opr0);
1577    return true;
1578  }
1579
1580  return false;
1581}
1582
1583bool AMDGPULibCalls::evaluateCall(CallInst *aCI, const FuncInfo &FInfo) {
1584  int numArgs = (int)aCI->arg_size();
1585  if (numArgs > 3)
1586    return false;
1587
1588  Constant *copr0 = nullptr;
1589  Constant *copr1 = nullptr;
1590  if (numArgs > 0) {
1591    if ((copr0 = dyn_cast<Constant>(aCI->getArgOperand(0))) == nullptr)
1592      return false;
1593  }
1594
1595  if (numArgs > 1) {
1596    if ((copr1 = dyn_cast<Constant>(aCI->getArgOperand(1))) == nullptr) {
1597      if (FInfo.getId() != AMDGPULibFunc::EI_SINCOS)
1598        return false;
1599    }
1600  }
1601
1602  // At this point, all arguments to aCI are constants.
1603
1604  // max vector size is 16, and sincos will generate two results.
1605  double DVal0[16], DVal1[16];
1606  int FuncVecSize = getVecSize(FInfo);
1607  bool hasTwoResults = (FInfo.getId() == AMDGPULibFunc::EI_SINCOS);
1608  if (FuncVecSize == 1) {
1609    if (!evaluateScalarMathFunc(FInfo, DVal0[0], DVal1[0], copr0, copr1)) {
1610      return false;
1611    }
1612  } else {
1613    ConstantDataVector *CDV0 = dyn_cast_or_null<ConstantDataVector>(copr0);
1614    ConstantDataVector *CDV1 = dyn_cast_or_null<ConstantDataVector>(copr1);
1615    for (int i = 0; i < FuncVecSize; ++i) {
1616      Constant *celt0 = CDV0 ? CDV0->getElementAsConstant(i) : nullptr;
1617      Constant *celt1 = CDV1 ? CDV1->getElementAsConstant(i) : nullptr;
1618      if (!evaluateScalarMathFunc(FInfo, DVal0[i], DVal1[i], celt0, celt1)) {
1619        return false;
1620      }
1621    }
1622  }
1623
1624  LLVMContext &context = aCI->getContext();
1625  Constant *nval0, *nval1;
1626  if (FuncVecSize == 1) {
1627    nval0 = ConstantFP::get(aCI->getType(), DVal0[0]);
1628    if (hasTwoResults)
1629      nval1 = ConstantFP::get(aCI->getType(), DVal1[0]);
1630  } else {
1631    if (getArgType(FInfo) == AMDGPULibFunc::F32) {
1632      SmallVector <float, 0> FVal0, FVal1;
1633      for (int i = 0; i < FuncVecSize; ++i)
1634        FVal0.push_back((float)DVal0[i]);
1635      ArrayRef<float> tmp0(FVal0);
1636      nval0 = ConstantDataVector::get(context, tmp0);
1637      if (hasTwoResults) {
1638        for (int i = 0; i < FuncVecSize; ++i)
1639          FVal1.push_back((float)DVal1[i]);
1640        ArrayRef<float> tmp1(FVal1);
1641        nval1 = ConstantDataVector::get(context, tmp1);
1642      }
1643    } else {
1644      ArrayRef<double> tmp0(DVal0);
1645      nval0 = ConstantDataVector::get(context, tmp0);
1646      if (hasTwoResults) {
1647        ArrayRef<double> tmp1(DVal1);
1648        nval1 = ConstantDataVector::get(context, tmp1);
1649      }
1650    }
1651  }
1652
1653  if (hasTwoResults) {
1654    // sincos
1655    assert(FInfo.getId() == AMDGPULibFunc::EI_SINCOS &&
1656           "math function with ptr arg not supported yet");
1657    new StoreInst(nval1, aCI->getArgOperand(1), aCI);
1658  }
1659
1660  replaceCall(aCI, nval0);
1661  return true;
1662}
1663
1664PreservedAnalyses AMDGPUSimplifyLibCallsPass::run(Function &F,
1665                                                  FunctionAnalysisManager &AM) {
1666  AMDGPULibCalls Simplifier;
1667  Simplifier.initNativeFuncs();
1668  Simplifier.initFunction(F, AM);
1669
1670  bool Changed = false;
1671
1672  LLVM_DEBUG(dbgs() << "AMDIC: process function ";
1673             F.printAsOperand(dbgs(), false, F.getParent()); dbgs() << '\n';);
1674
1675  for (auto &BB : F) {
1676    for (BasicBlock::iterator I = BB.begin(), E = BB.end(); I != E;) {
1677      // Ignore non-calls.
1678      CallInst *CI = dyn_cast<CallInst>(I);
1679      ++I;
1680
1681      if (CI) {
1682        if (Simplifier.fold(CI))
1683          Changed = true;
1684      }
1685    }
1686  }
1687  return Changed ? PreservedAnalyses::none() : PreservedAnalyses::all();
1688}
1689
1690PreservedAnalyses AMDGPUUseNativeCallsPass::run(Function &F,
1691                                                FunctionAnalysisManager &AM) {
1692  if (UseNative.empty())
1693    return PreservedAnalyses::all();
1694
1695  AMDGPULibCalls Simplifier;
1696  Simplifier.initNativeFuncs();
1697  Simplifier.initFunction(F, AM);
1698
1699  bool Changed = false;
1700  for (auto &BB : F) {
1701    for (BasicBlock::iterator I = BB.begin(), E = BB.end(); I != E;) {
1702      // Ignore non-calls.
1703      CallInst *CI = dyn_cast<CallInst>(I);
1704      ++I;
1705      if (CI && Simplifier.useNative(CI))
1706        Changed = true;
1707    }
1708  }
1709  return Changed ? PreservedAnalyses::none() : PreservedAnalyses::all();
1710}
1711