//===- AMDGPULibCalls.cpp -------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
/// \file
/// This file does AMD library function optimizations.
//
//===----------------------------------------------------------------------===//
#include "AMDGPU.h"
#include "AMDGPULibFunc.h"
#include "GCNSubtarget.h"
#include "llvm/Analysis/AssumptionCache.h"
#include "llvm/Analysis/TargetLibraryInfo.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/IR/AttributeMask.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/IntrinsicsAMDGPU.h"
#include "llvm/IR/MDBuilder.h"
#include "llvm/IR/PatternMatch.h"
#include "llvm/InitializePasses.h"
#include <cmath>
#define DEBUG_TYPE "amdgpu-simplifylib"
using namespace llvm;
using namespace llvm::PatternMatch;
static cl::opt<bool> EnablePreLink("amdgpu-prelink",
cl::desc("Enable pre-link mode optimizations"),
cl::init(false),
cl::Hidden);
static cl::list<std::string> UseNative("amdgpu-use-native",
cl::desc("Comma separated list of functions to replace with native, or all"),
cl::CommaSeparated, cl::ValueOptional,
cl::Hidden);
#define MATH_PI numbers::pi
#define MATH_E numbers::e
#define MATH_SQRT2 numbers::sqrt2
#define MATH_SQRT1_2 numbers::inv_sqrt2
namespace llvm {
class AMDGPULibCalls {
private:
const TargetLibraryInfo *TLInfo = nullptr;
AssumptionCache *AC = nullptr;
DominatorTree *DT = nullptr;
using FuncInfo = llvm::AMDGPULibFunc;
bool UnsafeFPMath = false;
// -fuse-native.
bool AllNative = false;
bool useNativeFunc(const StringRef F) const;
// Return a pointer (pointer expr) to the function if function definition with
// "FuncName" exists. It may create a new function prototype in pre-link mode.
FunctionCallee getFunction(Module *M, const FuncInfo &fInfo);
bool parseFunctionName(const StringRef &FMangledName, FuncInfo &FInfo);
bool TDOFold(CallInst *CI, const FuncInfo &FInfo);
/* Specialized optimizations */
// pow/powr/pown
bool fold_pow(FPMathOperator *FPOp, IRBuilder<> &B, const FuncInfo &FInfo);
// rootn
bool fold_rootn(FPMathOperator *FPOp, IRBuilder<> &B, const FuncInfo &FInfo);
// -fuse-native for sincos
bool sincosUseNative(CallInst *aCI, const FuncInfo &FInfo);
// evaluate calls if calls' arguments are constants.
bool evaluateScalarMathFunc(const FuncInfo &FInfo, double &Res0, double &Res1,
Constant *copr0, Constant *copr1);
bool evaluateCall(CallInst *aCI, const FuncInfo &FInfo);
/// Insert a value to sincos function \p Fsincos. Returns (value of sin, value
/// of cos, sincos call).
std::tuple<Value *, Value *, Value *> insertSinCos(Value *Arg,
FastMathFlags FMF,
IRBuilder<> &B,
FunctionCallee Fsincos);
// sin/cos
bool fold_sincos(FPMathOperator *FPOp, IRBuilder<> &B, const FuncInfo &FInfo);
// __read_pipe/__write_pipe
bool fold_read_write_pipe(CallInst *CI, IRBuilder<> &B,
const FuncInfo &FInfo);
// Get a scalar native builtin single argument FP function
FunctionCallee getNativeFunction(Module *M, const FuncInfo &FInfo);
/// Substitute a call to a known libcall with an intrinsic call. If \p
/// AllowMinSize is true, allow the replacement in a minsize function.
bool shouldReplaceLibcallWithIntrinsic(const CallInst *CI,
bool AllowMinSizeF32 = false,
bool AllowF64 = false,
bool AllowStrictFP = false);
void replaceLibCallWithSimpleIntrinsic(IRBuilder<> &B, CallInst *CI,
Intrinsic::ID IntrID);
bool tryReplaceLibcallWithSimpleIntrinsic(IRBuilder<> &B, CallInst *CI,
Intrinsic::ID IntrID,
bool AllowMinSizeF32 = false,
bool AllowF64 = false,
bool AllowStrictFP = false);
protected:
bool isUnsafeMath(const FPMathOperator *FPOp) const;
bool isUnsafeFiniteOnlyMath(const FPMathOperator *FPOp) const;
bool canIncreasePrecisionOfConstantFold(const FPMathOperator *FPOp) const;
static void replaceCall(Instruction *I, Value *With) {
I->replaceAllUsesWith(With);
I->eraseFromParent();
}
static void replaceCall(FPMathOperator *I, Value *With) {
replaceCall(cast<Instruction>(I), With);
}
public:
AMDGPULibCalls() = default;
bool fold(CallInst *CI);
void initFunction(Function &F, FunctionAnalysisManager &FAM);
void initNativeFuncs();
// Replace a normal math function call with that native version
bool useNative(CallInst *CI);
};
} // end namespace llvm
template <typename IRB>
static CallInst *CreateCallEx(IRB &B, FunctionCallee Callee, Value *Arg,
const Twine &Name = "") {
CallInst *R = B.CreateCall(Callee, Arg, Name);
if (Function *F = dyn_cast<Function>(Callee.getCallee()))
R->setCallingConv(F->getCallingConv());
return R;
}
template <typename IRB>
static CallInst *CreateCallEx2(IRB &B, FunctionCallee Callee, Value *Arg1,
Value *Arg2, const Twine &Name = "") {
CallInst *R = B.CreateCall(Callee, {Arg1, Arg2}, Name);
if (Function *F = dyn_cast<Function>(Callee.getCallee()))
R->setCallingConv(F->getCallingConv());
return R;
}
static FunctionType *getPownType(FunctionType *FT) {
Type *PowNExpTy = Type::getInt32Ty(FT->getContext());
if (VectorType *VecTy = dyn_cast<VectorType>(FT->getReturnType()))
PowNExpTy = VectorType::get(PowNExpTy, VecTy->getElementCount());
return FunctionType::get(FT->getReturnType(),
{FT->getParamType(0), PowNExpTy}, false);
}
// Data structures for table-driven optimizations.
// FuncTbl works for both f32 and f64 functions with 1 input argument
struct TableEntry {
double result;
double input;
};
/* a list of {result, input} */
static const TableEntry tbl_acos[] = {
{MATH_PI / 2.0, 0.0},
{MATH_PI / 2.0, -0.0},
{0.0, 1.0},
{MATH_PI, -1.0}
};
static const TableEntry tbl_acosh[] = {
{0.0, 1.0}
};
static const TableEntry tbl_acospi[] = {
{0.5, 0.0},
{0.5, -0.0},
{0.0, 1.0},
{1.0, -1.0}
};
static const TableEntry tbl_asin[] = {
{0.0, 0.0},
{-0.0, -0.0},
{MATH_PI / 2.0, 1.0},
{-MATH_PI / 2.0, -1.0}
};
static const TableEntry tbl_asinh[] = {
{0.0, 0.0},
{-0.0, -0.0}
};
static const TableEntry tbl_asinpi[] = {
{0.0, 0.0},
{-0.0, -0.0},
{0.5, 1.0},
{-0.5, -1.0}
};
static const TableEntry tbl_atan[] = {
{0.0, 0.0},
{-0.0, -0.0},
{MATH_PI / 4.0, 1.0},
{-MATH_PI / 4.0, -1.0}
};
static const TableEntry tbl_atanh[] = {
{0.0, 0.0},
{-0.0, -0.0}
};
static const TableEntry tbl_atanpi[] = {
{0.0, 0.0},
{-0.0, -0.0},
{0.25, 1.0},
{-0.25, -1.0}
};
static const TableEntry tbl_cbrt[] = {
{0.0, 0.0},
{-0.0, -0.0},
{1.0, 1.0},
{-1.0, -1.0},
};
static const TableEntry tbl_cos[] = {
{1.0, 0.0},
{1.0, -0.0}
};
static const TableEntry tbl_cosh[] = {
{1.0, 0.0},
{1.0, -0.0}
};
static const TableEntry tbl_cospi[] = {
{1.0, 0.0},
{1.0, -0.0}
};
static const TableEntry tbl_erfc[] = {
{1.0, 0.0},
{1.0, -0.0}
};
static const TableEntry tbl_erf[] = {
{0.0, 0.0},
{-0.0, -0.0}
};
static const TableEntry tbl_exp[] = {
{1.0, 0.0},
{1.0, -0.0},
{MATH_E, 1.0}
};
static const TableEntry tbl_exp2[] = {
{1.0, 0.0},
{1.0, -0.0},
{2.0, 1.0}
};
static const TableEntry tbl_exp10[] = {
{1.0, 0.0},
{1.0, -0.0},
{10.0, 1.0}
};
static const TableEntry tbl_expm1[] = {
{0.0, 0.0},
{-0.0, -0.0}
};
static const TableEntry tbl_log[] = {
{0.0, 1.0},
{1.0, MATH_E}
};
static const TableEntry tbl_log2[] = {
{0.0, 1.0},
{1.0, 2.0}
};
static const TableEntry tbl_log10[] = {
{0.0, 1.0},
{1.0, 10.0}
};
static const TableEntry tbl_rsqrt[] = {
{1.0, 1.0},
{MATH_SQRT1_2, 2.0}
};
static const TableEntry tbl_sin[] = {
{0.0, 0.0},
{-0.0, -0.0}
};
static const TableEntry tbl_sinh[] = {
{0.0, 0.0},
{-0.0, -0.0}
};
static const TableEntry tbl_sinpi[] = {
{0.0, 0.0},
{-0.0, -0.0}
};
static const TableEntry tbl_sqrt[] = {
{0.0, 0.0},
{1.0, 1.0},
{MATH_SQRT2, 2.0}
};
static const TableEntry tbl_tan[] = {
{0.0, 0.0},
{-0.0, -0.0}
};
static const TableEntry tbl_tanh[] = {
{0.0, 0.0},
{-0.0, -0.0}
};
static const TableEntry tbl_tanpi[] = {
{0.0, 0.0},
{-0.0, -0.0}
};
static const TableEntry tbl_tgamma[] = {
{1.0, 1.0},
{1.0, 2.0},
{2.0, 3.0},
{6.0, 4.0}
};
static bool HasNative(AMDGPULibFunc::EFuncId id) {
switch(id) {
case AMDGPULibFunc::EI_DIVIDE:
case AMDGPULibFunc::EI_COS:
case AMDGPULibFunc::EI_EXP:
case AMDGPULibFunc::EI_EXP2:
case AMDGPULibFunc::EI_EXP10:
case AMDGPULibFunc::EI_LOG:
case AMDGPULibFunc::EI_LOG2:
case AMDGPULibFunc::EI_LOG10:
case AMDGPULibFunc::EI_POWR:
case AMDGPULibFunc::EI_RECIP:
case AMDGPULibFunc::EI_RSQRT:
case AMDGPULibFunc::EI_SIN:
case AMDGPULibFunc::EI_SINCOS:
case AMDGPULibFunc::EI_SQRT:
case AMDGPULibFunc::EI_TAN:
return true;
default:;
}
return false;
}
using TableRef = ArrayRef<TableEntry>;
static TableRef getOptTable(AMDGPULibFunc::EFuncId id) {
switch(id) {
case AMDGPULibFunc::EI_ACOS: return TableRef(tbl_acos);
case AMDGPULibFunc::EI_ACOSH: return TableRef(tbl_acosh);
case AMDGPULibFunc::EI_ACOSPI: return TableRef(tbl_acospi);
case AMDGPULibFunc::EI_ASIN: return TableRef(tbl_asin);
case AMDGPULibFunc::EI_ASINH: return TableRef(tbl_asinh);
case AMDGPULibFunc::EI_ASINPI: return TableRef(tbl_asinpi);
case AMDGPULibFunc::EI_ATAN: return TableRef(tbl_atan);
case AMDGPULibFunc::EI_ATANH: return TableRef(tbl_atanh);
case AMDGPULibFunc::EI_ATANPI: return TableRef(tbl_atanpi);
case AMDGPULibFunc::EI_CBRT: return TableRef(tbl_cbrt);
case AMDGPULibFunc::EI_NCOS:
case AMDGPULibFunc::EI_COS: return TableRef(tbl_cos);
case AMDGPULibFunc::EI_COSH: return TableRef(tbl_cosh);
case AMDGPULibFunc::EI_COSPI: return TableRef(tbl_cospi);
case AMDGPULibFunc::EI_ERFC: return TableRef(tbl_erfc);
case AMDGPULibFunc::EI_ERF: return TableRef(tbl_erf);
case AMDGPULibFunc::EI_EXP: return TableRef(tbl_exp);
case AMDGPULibFunc::EI_NEXP2:
case AMDGPULibFunc::EI_EXP2: return TableRef(tbl_exp2);
case AMDGPULibFunc::EI_EXP10: return TableRef(tbl_exp10);
case AMDGPULibFunc::EI_EXPM1: return TableRef(tbl_expm1);
case AMDGPULibFunc::EI_LOG: return TableRef(tbl_log);
case AMDGPULibFunc::EI_NLOG2:
case AMDGPULibFunc::EI_LOG2: return TableRef(tbl_log2);
case AMDGPULibFunc::EI_LOG10: return TableRef(tbl_log10);
case AMDGPULibFunc::EI_NRSQRT:
case AMDGPULibFunc::EI_RSQRT: return TableRef(tbl_rsqrt);
case AMDGPULibFunc::EI_NSIN:
case AMDGPULibFunc::EI_SIN: return TableRef(tbl_sin);
case AMDGPULibFunc::EI_SINH: return TableRef(tbl_sinh);
case AMDGPULibFunc::EI_SINPI: return TableRef(tbl_sinpi);
case AMDGPULibFunc::EI_NSQRT:
case AMDGPULibFunc::EI_SQRT: return TableRef(tbl_sqrt);
case AMDGPULibFunc::EI_TAN: return TableRef(tbl_tan);
case AMDGPULibFunc::EI_TANH: return TableRef(tbl_tanh);
case AMDGPULibFunc::EI_TANPI: return TableRef(tbl_tanpi);
case AMDGPULibFunc::EI_TGAMMA: return TableRef(tbl_tgamma);
default:;
}
return TableRef();
}
static inline int getVecSize(const AMDGPULibFunc& FInfo) {
return FInfo.getLeads()[0].VectorSize;
}
static inline AMDGPULibFunc::EType getArgType(const AMDGPULibFunc& FInfo) {
return (AMDGPULibFunc::EType)FInfo.getLeads()[0].ArgType;
}
FunctionCallee AMDGPULibCalls::getFunction(Module *M, const FuncInfo &fInfo) {
// If we are doing PreLinkOpt, the function is external. So it is safe to
// use getOrInsertFunction() at this stage.
return EnablePreLink ? AMDGPULibFunc::getOrInsertFunction(M, fInfo)
: AMDGPULibFunc::getFunction(M, fInfo);
}
bool AMDGPULibCalls::parseFunctionName(const StringRef &FMangledName,
FuncInfo &FInfo) {
return AMDGPULibFunc::parse(FMangledName, FInfo);
}
bool AMDGPULibCalls::isUnsafeMath(const FPMathOperator *FPOp) const {
return UnsafeFPMath || FPOp->isFast();
}
bool AMDGPULibCalls::isUnsafeFiniteOnlyMath(const FPMathOperator *FPOp) const {
return UnsafeFPMath ||
(FPOp->hasApproxFunc() && FPOp->hasNoNaNs() && FPOp->hasNoInfs());
}
bool AMDGPULibCalls::canIncreasePrecisionOfConstantFold(
const FPMathOperator *FPOp) const {
// TODO: Refine to approxFunc or contract
return isUnsafeMath(FPOp);
}
void AMDGPULibCalls::initFunction(Function &F, FunctionAnalysisManager &FAM) {
UnsafeFPMath = F.getFnAttribute("unsafe-fp-math").getValueAsBool();
AC = &FAM.getResult<AssumptionAnalysis>(F);
TLInfo = &FAM.getResult<TargetLibraryAnalysis>(F);
DT = FAM.getCachedResult<DominatorTreeAnalysis>(F);
}
bool AMDGPULibCalls::useNativeFunc(const StringRef F) const {
return AllNative || llvm::is_contained(UseNative, F);
}
void AMDGPULibCalls::initNativeFuncs() {
AllNative = useNativeFunc("all") ||
(UseNative.getNumOccurrences() && UseNative.size() == 1 &&
UseNative.begin()->empty());
}
bool AMDGPULibCalls::sincosUseNative(CallInst *aCI, const FuncInfo &FInfo) {
bool native_sin = useNativeFunc("sin");
bool native_cos = useNativeFunc("cos");
if (native_sin && native_cos) {
Module *M = aCI->getModule();
Value *opr0 = aCI->getArgOperand(0);
AMDGPULibFunc nf;
nf.getLeads()[0].ArgType = FInfo.getLeads()[0].ArgType;
nf.getLeads()[0].VectorSize = FInfo.getLeads()[0].VectorSize;
nf.setPrefix(AMDGPULibFunc::NATIVE);
nf.setId(AMDGPULibFunc::EI_SIN);
FunctionCallee sinExpr = getFunction(M, nf);
nf.setPrefix(AMDGPULibFunc::NATIVE);
nf.setId(AMDGPULibFunc::EI_COS);
FunctionCallee cosExpr = getFunction(M, nf);
if (sinExpr && cosExpr) {
Value *sinval =
CallInst::Create(sinExpr, opr0, "splitsin", aCI->getIterator());
Value *cosval =
CallInst::Create(cosExpr, opr0, "splitcos", aCI->getIterator());
new StoreInst(cosval, aCI->getArgOperand(1), aCI->getIterator());
DEBUG_WITH_TYPE("usenative", dbgs() << "<useNative> replace " << *aCI
<< " with native version of sin/cos");
replaceCall(aCI, sinval);
return true;
}
}
return false;
}
bool AMDGPULibCalls::useNative(CallInst *aCI) {
Function *Callee = aCI->getCalledFunction();
if (!Callee || aCI->isNoBuiltin())
return false;
FuncInfo FInfo;
if (!parseFunctionName(Callee->getName(), FInfo) || !FInfo.isMangled() ||
FInfo.getPrefix() != AMDGPULibFunc::NOPFX ||
getArgType(FInfo) == AMDGPULibFunc::F64 || !HasNative(FInfo.getId()) ||
!(AllNative || useNativeFunc(FInfo.getName()))) {
return false;
}
if (FInfo.getId() == AMDGPULibFunc::EI_SINCOS)
return sincosUseNative(aCI, FInfo);
FInfo.setPrefix(AMDGPULibFunc::NATIVE);
FunctionCallee F = getFunction(aCI->getModule(), FInfo);
if (!F)
return false;
aCI->setCalledFunction(F);
DEBUG_WITH_TYPE("usenative", dbgs() << "<useNative> replace " << *aCI
<< " with native version");
return true;
}
// Clang emits call of __read_pipe_2 or __read_pipe_4 for OpenCL read_pipe
// builtin, with appended type size and alignment arguments, where 2 or 4
// indicates the original number of arguments. The library has optimized version
// of __read_pipe_2/__read_pipe_4 when the type size and alignment has the same
// power of 2 value. This function transforms __read_pipe_2 to __read_pipe_2_N
// for such cases where N is the size in bytes of the type (N = 1, 2, 4, 8, ...,
// 128). The same for __read_pipe_4, write_pipe_2, and write_pipe_4.
bool AMDGPULibCalls::fold_read_write_pipe(CallInst *CI, IRBuilder<> &B,
const FuncInfo &FInfo) {
auto *Callee = CI->getCalledFunction();
if (!Callee->isDeclaration())
return false;
assert(Callee->hasName() && "Invalid read_pipe/write_pipe function");
auto *M = Callee->getParent();
std::string Name = std::string(Callee->getName());
auto NumArg = CI->arg_size();
if (NumArg != 4 && NumArg != 6)
return false;
ConstantInt *PacketSize =
dyn_cast<ConstantInt>(CI->getArgOperand(NumArg - 2));
ConstantInt *PacketAlign =
dyn_cast<ConstantInt>(CI->getArgOperand(NumArg - 1));
if (!PacketSize || !PacketAlign)
return false;
unsigned Size = PacketSize->getZExtValue();
Align Alignment = PacketAlign->getAlignValue();
if (Alignment != Size)
return false;
unsigned PtrArgLoc = CI->arg_size() - 3;
Value *PtrArg = CI->getArgOperand(PtrArgLoc);
Type *PtrTy = PtrArg->getType();
SmallVector<llvm::Type *, 6> ArgTys;
for (unsigned I = 0; I != PtrArgLoc; ++I)
ArgTys.push_back(CI->getArgOperand(I)->getType());
ArgTys.push_back(PtrTy);
Name = Name + "_" + std::to_string(Size);
auto *FTy = FunctionType::get(Callee->getReturnType(),
ArrayRef<Type *>(ArgTys), false);
AMDGPULibFunc NewLibFunc(Name, FTy);
FunctionCallee F = AMDGPULibFunc::getOrInsertFunction(M, NewLibFunc);
if (!F)
return false;
SmallVector<Value *, 6> Args;
for (unsigned I = 0; I != PtrArgLoc; ++I)
Args.push_back(CI->getArgOperand(I));
Args.push_back(PtrArg);
auto *NCI = B.CreateCall(F, Args);
NCI->setAttributes(CI->getAttributes());
CI->replaceAllUsesWith(NCI);
CI->dropAllReferences();
CI->eraseFromParent();
return true;
}
static bool isKnownIntegral(const Value *V, const DataLayout &DL,
FastMathFlags FMF) {
if (isa<PoisonValue>(V))
return true;
if (isa<UndefValue>(V))
return false;
if (const ConstantFP *CF = dyn_cast<ConstantFP>(V))
return CF->getValueAPF().isInteger();
auto *VFVTy = dyn_cast<FixedVectorType>(V->getType());
const Constant *CV = dyn_cast<Constant>(V);
if (VFVTy && CV) {
unsigned NumElts = VFVTy->getNumElements();
for (unsigned i = 0; i != NumElts; ++i) {
Constant *Elt = CV->getAggregateElement(i);
if (!Elt)
return false;
if (isa<PoisonValue>(Elt))
continue;
const ConstantFP *CFP = dyn_cast<ConstantFP>(Elt);
if (!CFP || !CFP->getValue().isInteger())
return false;
}
return true;
}
const Instruction *I = dyn_cast<Instruction>(V);
if (!I)
return false;
switch (I->getOpcode()) {
case Instruction::SIToFP:
case Instruction::UIToFP:
// TODO: Could check nofpclass(inf) on incoming argument
if (FMF.noInfs())
return true;
// Need to check int size cannot produce infinity, which computeKnownFPClass
// knows how to do already.
return isKnownNeverInfinity(I, /*Depth=*/0, SimplifyQuery(DL));
case Instruction::Call: {
const CallInst *CI = cast<CallInst>(I);
switch (CI->getIntrinsicID()) {
case Intrinsic::trunc:
case Intrinsic::floor:
case Intrinsic::ceil:
case Intrinsic::rint:
case Intrinsic::nearbyint:
case Intrinsic::round:
case Intrinsic::roundeven:
return (FMF.noInfs() && FMF.noNaNs()) ||
isKnownNeverInfOrNaN(I, /*Depth=*/0, SimplifyQuery(DL));
default:
break;
}
break;
}
default:
break;
}
return false;
}
// This function returns false if no change; return true otherwise.
bool AMDGPULibCalls::fold(CallInst *CI) {
Function *Callee = CI->getCalledFunction();
// Ignore indirect calls.
if (!Callee || Callee->isIntrinsic() || CI->isNoBuiltin())
return false;
FuncInfo FInfo;
if (!parseFunctionName(Callee->getName(), FInfo))
return false;
// Further check the number of arguments to see if they match.
// TODO: Check calling convention matches too
if (!FInfo.isCompatibleSignature(CI->getFunctionType()))
return false;
LLVM_DEBUG(dbgs() << "AMDIC: try folding " << *CI << '\n');
if (TDOFold(CI, FInfo))
return true;
IRBuilder<> B(CI);
if (CI->isStrictFP())
B.setIsFPConstrained(true);
if (FPMathOperator *FPOp = dyn_cast<FPMathOperator>(CI)) {
// Under unsafe-math, evaluate calls if possible.
// According to Brian Sumner, we can do this for all f32 function calls
// using host's double function calls.
if (canIncreasePrecisionOfConstantFold(FPOp) && evaluateCall(CI, FInfo))
return true;
// Copy fast flags from the original call.
FastMathFlags FMF = FPOp->getFastMathFlags();
B.setFastMathFlags(FMF);
// Specialized optimizations for each function call.
//
// TODO: Handle native functions
switch (FInfo.getId()) {
case AMDGPULibFunc::EI_EXP:
if (FMF.none())
return false;
return tryReplaceLibcallWithSimpleIntrinsic(B, CI, Intrinsic::exp,
FMF.approxFunc());
case AMDGPULibFunc::EI_EXP2:
if (FMF.none())
return false;
return tryReplaceLibcallWithSimpleIntrinsic(B, CI, Intrinsic::exp2,
FMF.approxFunc());
case AMDGPULibFunc::EI_LOG:
if (FMF.none())
return false;
return tryReplaceLibcallWithSimpleIntrinsic(B, CI, Intrinsic::log,
FMF.approxFunc());
case AMDGPULibFunc::EI_LOG2:
if (FMF.none())
return false;
return tryReplaceLibcallWithSimpleIntrinsic(B, CI, Intrinsic::log2,
FMF.approxFunc());
case AMDGPULibFunc::EI_LOG10:
if (FMF.none())
return false;
return tryReplaceLibcallWithSimpleIntrinsic(B, CI, Intrinsic::log10,
FMF.approxFunc());
case AMDGPULibFunc::EI_FMIN:
return tryReplaceLibcallWithSimpleIntrinsic(B, CI, Intrinsic::minnum,
true, true);
case AMDGPULibFunc::EI_FMAX:
return tryReplaceLibcallWithSimpleIntrinsic(B, CI, Intrinsic::maxnum,
true, true);
case AMDGPULibFunc::EI_FMA:
return tryReplaceLibcallWithSimpleIntrinsic(B, CI, Intrinsic::fma, true,
true);
case AMDGPULibFunc::EI_MAD:
return tryReplaceLibcallWithSimpleIntrinsic(B, CI, Intrinsic::fmuladd,
true, true);
case AMDGPULibFunc::EI_FABS:
return tryReplaceLibcallWithSimpleIntrinsic(B, CI, Intrinsic::fabs, true,
true, true);
case AMDGPULibFunc::EI_COPYSIGN:
return tryReplaceLibcallWithSimpleIntrinsic(B, CI, Intrinsic::copysign,
true, true, true);
case AMDGPULibFunc::EI_FLOOR:
return tryReplaceLibcallWithSimpleIntrinsic(B, CI, Intrinsic::floor, true,
true);
case AMDGPULibFunc::EI_CEIL:
return tryReplaceLibcallWithSimpleIntrinsic(B, CI, Intrinsic::ceil, true,
true);
case AMDGPULibFunc::EI_TRUNC:
return tryReplaceLibcallWithSimpleIntrinsic(B, CI, Intrinsic::trunc, true,
true);
case AMDGPULibFunc::EI_RINT:
return tryReplaceLibcallWithSimpleIntrinsic(B, CI, Intrinsic::rint, true,
true);
case AMDGPULibFunc::EI_ROUND:
return tryReplaceLibcallWithSimpleIntrinsic(B, CI, Intrinsic::round, true,
true);
case AMDGPULibFunc::EI_LDEXP: {
if (!shouldReplaceLibcallWithIntrinsic(CI, true, true))
return false;
Value *Arg1 = CI->getArgOperand(1);
if (VectorType *VecTy = dyn_cast<VectorType>(CI->getType());
VecTy && !isa<VectorType>(Arg1->getType())) {
Value *SplatArg1 = B.CreateVectorSplat(VecTy->getElementCount(), Arg1);
CI->setArgOperand(1, SplatArg1);
}
CI->setCalledFunction(Intrinsic::getDeclaration(
CI->getModule(), Intrinsic::ldexp,
{CI->getType(), CI->getArgOperand(1)->getType()}));
return true;
}
case AMDGPULibFunc::EI_POW: {
Module *M = Callee->getParent();
AMDGPULibFunc PowrInfo(AMDGPULibFunc::EI_POWR, FInfo);
FunctionCallee PowrFunc = getFunction(M, PowrInfo);
CallInst *Call = cast<CallInst>(FPOp);
// pow(x, y) -> powr(x, y) for x >= -0.0
// TODO: Account for flags on current call
if (PowrFunc &&
cannotBeOrderedLessThanZero(
FPOp->getOperand(0), /*Depth=*/0,
SimplifyQuery(M->getDataLayout(), TLInfo, DT, AC, Call))) {
Call->setCalledFunction(PowrFunc);
return fold_pow(FPOp, B, PowrInfo) || true;
}
// pow(x, y) -> pown(x, y) for known integral y
if (isKnownIntegral(FPOp->getOperand(1), M->getDataLayout(),
FPOp->getFastMathFlags())) {
FunctionType *PownType = getPownType(CI->getFunctionType());
AMDGPULibFunc PownInfo(AMDGPULibFunc::EI_POWN, PownType, true);
FunctionCallee PownFunc = getFunction(M, PownInfo);
if (PownFunc) {
// TODO: If the incoming integral value is an sitofp/uitofp, it won't
// fold out without a known range. We can probably take the source
// value directly.
Value *CastedArg =
B.CreateFPToSI(FPOp->getOperand(1), PownType->getParamType(1));
// Have to drop any nofpclass attributes on the original call site.
Call->removeParamAttrs(
1, AttributeFuncs::typeIncompatible(CastedArg->getType()));
Call->setCalledFunction(PownFunc);
Call->setArgOperand(1, CastedArg);
return fold_pow(FPOp, B, PownInfo) || true;
}
}
return fold_pow(FPOp, B, FInfo);
}
case AMDGPULibFunc::EI_POWR:
case AMDGPULibFunc::EI_POWN:
return fold_pow(FPOp, B, FInfo);
case AMDGPULibFunc::EI_ROOTN:
return fold_rootn(FPOp, B, FInfo);
case AMDGPULibFunc::EI_SQRT:
// TODO: Allow with strictfp + constrained intrinsic
return tryReplaceLibcallWithSimpleIntrinsic(
B, CI, Intrinsic::sqrt, true, true, /*AllowStrictFP=*/false);
case AMDGPULibFunc::EI_COS:
case AMDGPULibFunc::EI_SIN:
return fold_sincos(FPOp, B, FInfo);
default:
break;
}
} else {
// Specialized optimizations for each function call
switch (FInfo.getId()) {
case AMDGPULibFunc::EI_READ_PIPE_2:
case AMDGPULibFunc::EI_READ_PIPE_4:
case AMDGPULibFunc::EI_WRITE_PIPE_2:
case AMDGPULibFunc::EI_WRITE_PIPE_4:
return fold_read_write_pipe(CI, B, FInfo);
default:
break;
}
}
return false;
}
bool AMDGPULibCalls::TDOFold(CallInst *CI, const FuncInfo &FInfo) {
// Table-Driven optimization
const TableRef tr = getOptTable(FInfo.getId());
if (tr.empty())
return false;
int const sz = (int)tr.size();
Value *opr0 = CI->getArgOperand(0);
if (getVecSize(FInfo) > 1) {
if (ConstantDataVector *CV = dyn_cast<ConstantDataVector>(opr0)) {
SmallVector<double, 0> DVal;
for (int eltNo = 0; eltNo < getVecSize(FInfo); ++eltNo) {
ConstantFP *eltval = dyn_cast<ConstantFP>(
CV->getElementAsConstant((unsigned)eltNo));
assert(eltval && "Non-FP arguments in math function!");
bool found = false;
for (int i=0; i < sz; ++i) {
if (eltval->isExactlyValue(tr[i].input)) {
DVal.push_back(tr[i].result);
found = true;
break;
}
}
if (!found) {
// This vector constants not handled yet.
return false;
}
}
LLVMContext &context = CI->getParent()->getParent()->getContext();
Constant *nval;
if (getArgType(FInfo) == AMDGPULibFunc::F32) {
SmallVector<float, 0> FVal;
for (double D : DVal)
FVal.push_back((float)D);
ArrayRef<float> tmp(FVal);
nval = ConstantDataVector::get(context, tmp);
} else { // F64
ArrayRef<double> tmp(DVal);
nval = ConstantDataVector::get(context, tmp);
}
LLVM_DEBUG(errs() << "AMDIC: " << *CI << " ---> " << *nval << "\n");
replaceCall(CI, nval);
return true;
}
} else {
// Scalar version
if (ConstantFP *CF = dyn_cast<ConstantFP>(opr0)) {
for (int i = 0; i < sz; ++i) {
if (CF->isExactlyValue(tr[i].input)) {
Value *nval = ConstantFP::get(CF->getType(), tr[i].result);
LLVM_DEBUG(errs() << "AMDIC: " << *CI << " ---> " << *nval << "\n");
replaceCall(CI, nval);
return true;
}
}
}
}
return false;
}
namespace llvm {
static double log2(double V) {
#if _XOPEN_SOURCE >= 600 || defined(_ISOC99_SOURCE) || _POSIX_C_SOURCE >= 200112L
return ::log2(V);
#else
return log(V) / numbers::ln2;
#endif
}
} // namespace llvm
bool AMDGPULibCalls::fold_pow(FPMathOperator *FPOp, IRBuilder<> &B,
const FuncInfo &FInfo) {
assert((FInfo.getId() == AMDGPULibFunc::EI_POW ||
FInfo.getId() == AMDGPULibFunc::EI_POWR ||
FInfo.getId() == AMDGPULibFunc::EI_POWN) &&
"fold_pow: encounter a wrong function call");
Module *M = B.GetInsertBlock()->getModule();
Type *eltType = FPOp->getType()->getScalarType();
Value *opr0 = FPOp->getOperand(0);
Value *opr1 = FPOp->getOperand(1);
const APFloat *CF = nullptr;
const APInt *CINT = nullptr;
if (!match(opr1, m_APFloatAllowPoison(CF)))
match(opr1, m_APIntAllowPoison(CINT));
// 0x1111111 means that we don't do anything for this call.
int ci_opr1 = (CINT ? (int)CINT->getSExtValue() : 0x1111111);
if ((CF && CF->isZero()) || (CINT && ci_opr1 == 0)) {
// pow/powr/pown(x, 0) == 1
LLVM_DEBUG(errs() << "AMDIC: " << *FPOp << " ---> 1\n");
Constant *cnval = ConstantFP::get(eltType, 1.0);
if (getVecSize(FInfo) > 1) {
cnval = ConstantDataVector::getSplat(getVecSize(FInfo), cnval);
}
replaceCall(FPOp, cnval);
return true;
}
if ((CF && CF->isExactlyValue(1.0)) || (CINT && ci_opr1 == 1)) {
// pow/powr/pown(x, 1.0) = x
LLVM_DEBUG(errs() << "AMDIC: " << *FPOp << " ---> " << *opr0 << "\n");
replaceCall(FPOp, opr0);
return true;
}
if ((CF && CF->isExactlyValue(2.0)) || (CINT && ci_opr1 == 2)) {
// pow/powr/pown(x, 2.0) = x*x
LLVM_DEBUG(errs() << "AMDIC: " << *FPOp << " ---> " << *opr0 << " * "
<< *opr0 << "\n");
Value *nval = B.CreateFMul(opr0, opr0, "__pow2");
replaceCall(FPOp, nval);
return true;
}
if ((CF && CF->isExactlyValue(-1.0)) || (CINT && ci_opr1 == -1)) {
// pow/powr/pown(x, -1.0) = 1.0/x
LLVM_DEBUG(errs() << "AMDIC: " << *FPOp << " ---> 1 / " << *opr0 << "\n");
Constant *cnval = ConstantFP::get(eltType, 1.0);
if (getVecSize(FInfo) > 1) {
cnval = ConstantDataVector::getSplat(getVecSize(FInfo), cnval);
}
Value *nval = B.CreateFDiv(cnval, opr0, "__powrecip");
replaceCall(FPOp, nval);
return true;
}
if (CF && (CF->isExactlyValue(0.5) || CF->isExactlyValue(-0.5))) {
// pow[r](x, [-]0.5) = sqrt(x)
bool issqrt = CF->isExactlyValue(0.5);
if (FunctionCallee FPExpr =
getFunction(M, AMDGPULibFunc(issqrt ? AMDGPULibFunc::EI_SQRT
: AMDGPULibFunc::EI_RSQRT,
FInfo))) {
LLVM_DEBUG(errs() << "AMDIC: " << *FPOp << " ---> " << FInfo.getName()
<< '(' << *opr0 << ")\n");
Value *nval = CreateCallEx(B,FPExpr, opr0, issqrt ? "__pow2sqrt"
: "__pow2rsqrt");
replaceCall(FPOp, nval);
return true;
}
}
if (!isUnsafeFiniteOnlyMath(FPOp))
return false;
// Unsafe Math optimization
// Remember that ci_opr1 is set if opr1 is integral
if (CF) {
double dval = (getArgType(FInfo) == AMDGPULibFunc::F32)
? (double)CF->convertToFloat()
: CF->convertToDouble();
int ival = (int)dval;
if ((double)ival == dval) {
ci_opr1 = ival;
} else
ci_opr1 = 0x11111111;
}
// pow/powr/pown(x, c) = [1/](x*x*..x); where
// trunc(c) == c && the number of x == c && |c| <= 12
unsigned abs_opr1 = (ci_opr1 < 0) ? -ci_opr1 : ci_opr1;
if (abs_opr1 <= 12) {
Constant *cnval;
Value *nval;
if (abs_opr1 == 0) {
cnval = ConstantFP::get(eltType, 1.0);
if (getVecSize(FInfo) > 1) {
cnval = ConstantDataVector::getSplat(getVecSize(FInfo), cnval);
}
nval = cnval;
} else {
Value *valx2 = nullptr;
nval = nullptr;
while (abs_opr1 > 0) {
valx2 = valx2 ? B.CreateFMul(valx2, valx2, "__powx2") : opr0;
if (abs_opr1 & 1) {
nval = nval ? B.CreateFMul(nval, valx2, "__powprod") : valx2;
}
abs_opr1 >>= 1;
}
}
if (ci_opr1 < 0) {
cnval = ConstantFP::get(eltType, 1.0);
if (getVecSize(FInfo) > 1) {
cnval = ConstantDataVector::getSplat(getVecSize(FInfo), cnval);
}
nval = B.CreateFDiv(cnval, nval, "__1powprod");
}
LLVM_DEBUG(errs() << "AMDIC: " << *FPOp << " ---> "
<< ((ci_opr1 < 0) ? "1/prod(" : "prod(") << *opr0
<< ")\n");
replaceCall(FPOp, nval);
return true;
}
// If we should use the generic intrinsic instead of emitting a libcall
const bool ShouldUseIntrinsic = eltType->isFloatTy() || eltType->isHalfTy();
// powr ---> exp2(y * log2(x))
// pown/pow ---> powr(fabs(x), y) | (x & ((int)y << 31))
FunctionCallee ExpExpr;
if (ShouldUseIntrinsic)
ExpExpr = Intrinsic::getDeclaration(M, Intrinsic::exp2, {FPOp->getType()});
else {
ExpExpr = getFunction(M, AMDGPULibFunc(AMDGPULibFunc::EI_EXP2, FInfo));
if (!ExpExpr)
return false;
}
bool needlog = false;
bool needabs = false;
bool needcopysign = false;
Constant *cnval = nullptr;
if (getVecSize(FInfo) == 1) {
CF = nullptr;
match(opr0, m_APFloatAllowPoison(CF));
if (CF) {
double V = (getArgType(FInfo) == AMDGPULibFunc::F32)
? (double)CF->convertToFloat()
: CF->convertToDouble();
V = log2(std::abs(V));
cnval = ConstantFP::get(eltType, V);
needcopysign = (FInfo.getId() != AMDGPULibFunc::EI_POWR) &&
CF->isNegative();
} else {
needlog = true;
needcopysign = needabs = FInfo.getId() != AMDGPULibFunc::EI_POWR;
}
} else {
ConstantDataVector *CDV = dyn_cast<ConstantDataVector>(opr0);
if (!CDV) {
needlog = true;
needcopysign = needabs = FInfo.getId() != AMDGPULibFunc::EI_POWR;
} else {
assert ((int)CDV->getNumElements() == getVecSize(FInfo) &&
"Wrong vector size detected");
SmallVector<double, 0> DVal;
for (int i=0; i < getVecSize(FInfo); ++i) {
double V = CDV->getElementAsAPFloat(i).convertToDouble();
if (V < 0.0) needcopysign = true;
V = log2(std::abs(V));
DVal.push_back(V);
}
if (getArgType(FInfo) == AMDGPULibFunc::F32) {
SmallVector<float, 0> FVal;
for (double D : DVal)
FVal.push_back((float)D);
ArrayRef<float> tmp(FVal);
cnval = ConstantDataVector::get(M->getContext(), tmp);
} else {
ArrayRef<double> tmp(DVal);
cnval = ConstantDataVector::get(M->getContext(), tmp);
}
}
}
if (needcopysign && (FInfo.getId() == AMDGPULibFunc::EI_POW)) {
// We cannot handle corner cases for a general pow() function, give up
// unless y is a constant integral value. Then proceed as if it were pown.
if (!isKnownIntegral(opr1, M->getDataLayout(), FPOp->getFastMathFlags()))
return false;
}
Value *nval;
if (needabs) {
nval = B.CreateUnaryIntrinsic(Intrinsic::fabs, opr0, nullptr, "__fabs");
} else {
nval = cnval ? cnval : opr0;
}
if (needlog) {
FunctionCallee LogExpr;
if (ShouldUseIntrinsic) {
LogExpr =
Intrinsic::getDeclaration(M, Intrinsic::log2, {FPOp->getType()});
} else {
LogExpr = getFunction(M, AMDGPULibFunc(AMDGPULibFunc::EI_LOG2, FInfo));
if (!LogExpr)
return false;
}
nval = CreateCallEx(B,LogExpr, nval, "__log2");
}
if (FInfo.getId() == AMDGPULibFunc::EI_POWN) {
// convert int(32) to fp(f32 or f64)
opr1 = B.CreateSIToFP(opr1, nval->getType(), "pownI2F");
}
nval = B.CreateFMul(opr1, nval, "__ylogx");
nval = CreateCallEx(B,ExpExpr, nval, "__exp2");
if (needcopysign) {
Type* nTyS = B.getIntNTy(eltType->getPrimitiveSizeInBits());
Type *nTy = FPOp->getType()->getWithNewType(nTyS);
unsigned size = nTy->getScalarSizeInBits();
Value *opr_n = FPOp->getOperand(1);
if (opr_n->getType()->getScalarType()->isIntegerTy())
opr_n = B.CreateZExtOrTrunc(opr_n, nTy, "__ytou");
else
opr_n = B.CreateFPToSI(opr1, nTy, "__ytou");
Value *sign = B.CreateShl(opr_n, size-1, "__yeven");
sign = B.CreateAnd(B.CreateBitCast(opr0, nTy), sign, "__pow_sign");
nval = B.CreateOr(B.CreateBitCast(nval, nTy), sign);
nval = B.CreateBitCast(nval, opr0->getType());
}
LLVM_DEBUG(errs() << "AMDIC: " << *FPOp << " ---> "
<< "exp2(" << *opr1 << " * log2(" << *opr0 << "))\n");
replaceCall(FPOp, nval);
return true;
}
bool AMDGPULibCalls::fold_rootn(FPMathOperator *FPOp, IRBuilder<> &B,
const FuncInfo &FInfo) {
Value *opr0 = FPOp->getOperand(0);
Value *opr1 = FPOp->getOperand(1);
const APInt *CINT = nullptr;
if (!match(opr1, m_APIntAllowPoison(CINT)))
return false;
Function *Parent = B.GetInsertBlock()->getParent();
int ci_opr1 = (int)CINT->getSExtValue();
if (ci_opr1 == 1 && !Parent->hasFnAttribute(Attribute::StrictFP)) {
// rootn(x, 1) = x
//
// TODO: Insert constrained canonicalize for strictfp case.
LLVM_DEBUG(errs() << "AMDIC: " << *FPOp << " ---> " << *opr0 << '\n');
replaceCall(FPOp, opr0);
return true;
}
Module *M = B.GetInsertBlock()->getModule();
CallInst *CI = cast<CallInst>(FPOp);
if (ci_opr1 == 2 &&
shouldReplaceLibcallWithIntrinsic(CI,
/*AllowMinSizeF32=*/true,
/*AllowF64=*/true)) {
// rootn(x, 2) = sqrt(x)
LLVM_DEBUG(errs() << "AMDIC: " << *FPOp << " ---> sqrt(" << *opr0 << ")\n");
CallInst *NewCall = B.CreateUnaryIntrinsic(Intrinsic::sqrt, opr0, CI);
NewCall->takeName(CI);
// OpenCL rootn has a looser ulp of 2 requirement than sqrt, so add some
// metadata.
MDBuilder MDHelper(M->getContext());
MDNode *FPMD = MDHelper.createFPMath(std::max(FPOp->getFPAccuracy(), 2.0f));
NewCall->setMetadata(LLVMContext::MD_fpmath, FPMD);
replaceCall(CI, NewCall);
return true;
}
if (ci_opr1 == 3) { // rootn(x, 3) = cbrt(x)
if (FunctionCallee FPExpr =
getFunction(M, AMDGPULibFunc(AMDGPULibFunc::EI_CBRT, FInfo))) {
LLVM_DEBUG(errs() << "AMDIC: " << *FPOp << " ---> cbrt(" << *opr0
<< ")\n");
Value *nval = CreateCallEx(B,FPExpr, opr0, "__rootn2cbrt");
replaceCall(FPOp, nval);
return true;
}
} else if (ci_opr1 == -1) { // rootn(x, -1) = 1.0/x
LLVM_DEBUG(errs() << "AMDIC: " << *FPOp << " ---> 1.0 / " << *opr0 << "\n");
Value *nval = B.CreateFDiv(ConstantFP::get(opr0->getType(), 1.0),
opr0,
"__rootn2div");
replaceCall(FPOp, nval);
return true;
}
if (ci_opr1 == -2 &&
shouldReplaceLibcallWithIntrinsic(CI,
/*AllowMinSizeF32=*/true,
/*AllowF64=*/true)) {
// rootn(x, -2) = rsqrt(x)
// The original rootn had looser ulp requirements than the resultant sqrt
// and fdiv.
MDBuilder MDHelper(M->getContext());
MDNode *FPMD = MDHelper.createFPMath(std::max(FPOp->getFPAccuracy(), 2.0f));
// TODO: Could handle strictfp but need to fix strict sqrt emission
FastMathFlags FMF = FPOp->getFastMathFlags();
FMF.setAllowContract(true);
CallInst *Sqrt = B.CreateUnaryIntrinsic(Intrinsic::sqrt, opr0, CI);
Instruction *RSqrt = cast<Instruction>(
B.CreateFDiv(ConstantFP::get(opr0->getType(), 1.0), Sqrt));
Sqrt->setFastMathFlags(FMF);
RSqrt->setFastMathFlags(FMF);
RSqrt->setMetadata(LLVMContext::MD_fpmath, FPMD);
LLVM_DEBUG(errs() << "AMDIC: " << *FPOp << " ---> rsqrt(" << *opr0
<< ")\n");
replaceCall(CI, RSqrt);
return true;
}
return false;
}
// Get a scalar native builtin single argument FP function
FunctionCallee AMDGPULibCalls::getNativeFunction(Module *M,
const FuncInfo &FInfo) {
if (getArgType(FInfo) == AMDGPULibFunc::F64 || !HasNative(FInfo.getId()))
return nullptr;
FuncInfo nf = FInfo;
nf.setPrefix(AMDGPULibFunc::NATIVE);
return getFunction(M, nf);
}
// Some library calls are just wrappers around llvm intrinsics, but compiled
// conservatively. Preserve the flags from the original call site by
// substituting them with direct calls with all the flags.
bool AMDGPULibCalls::shouldReplaceLibcallWithIntrinsic(const CallInst *CI,
bool AllowMinSizeF32,
bool AllowF64,
bool AllowStrictFP) {
Type *FltTy = CI->getType()->getScalarType();
const bool IsF32 = FltTy->isFloatTy();
// f64 intrinsics aren't implemented for most operations.
if (!IsF32 && !FltTy->isHalfTy() && (!AllowF64 || !FltTy->isDoubleTy()))
return false;
// We're implicitly inlining by replacing the libcall with the intrinsic, so
// don't do it for noinline call sites.
if (CI->isNoInline())
return false;
const Function *ParentF = CI->getFunction();
// TODO: Handle strictfp
if (!AllowStrictFP && ParentF->hasFnAttribute(Attribute::StrictFP))
return false;
if (IsF32 && !AllowMinSizeF32 && ParentF->hasMinSize())
return false;
return true;
}
void AMDGPULibCalls::replaceLibCallWithSimpleIntrinsic(IRBuilder<> &B,
CallInst *CI,
Intrinsic::ID IntrID) {
if (CI->arg_size() == 2) {
Value *Arg0 = CI->getArgOperand(0);
Value *Arg1 = CI->getArgOperand(1);
VectorType *Arg0VecTy = dyn_cast<VectorType>(Arg0->getType());
VectorType *Arg1VecTy = dyn_cast<VectorType>(Arg1->getType());
if (Arg0VecTy && !Arg1VecTy) {
Value *SplatRHS = B.CreateVectorSplat(Arg0VecTy->getElementCount(), Arg1);
CI->setArgOperand(1, SplatRHS);
} else if (!Arg0VecTy && Arg1VecTy) {
Value *SplatLHS = B.CreateVectorSplat(Arg1VecTy->getElementCount(), Arg0);
CI->setArgOperand(0, SplatLHS);
}
}
CI->setCalledFunction(
Intrinsic::getDeclaration(CI->getModule(), IntrID, {CI->getType()}));
}
bool AMDGPULibCalls::tryReplaceLibcallWithSimpleIntrinsic(
IRBuilder<> &B, CallInst *CI, Intrinsic::ID IntrID, bool AllowMinSizeF32,
bool AllowF64, bool AllowStrictFP) {
if (!shouldReplaceLibcallWithIntrinsic(CI, AllowMinSizeF32, AllowF64,
AllowStrictFP))
return false;
replaceLibCallWithSimpleIntrinsic(B, CI, IntrID);
return true;
}
std::tuple<Value *, Value *, Value *>
AMDGPULibCalls::insertSinCos(Value *Arg, FastMathFlags FMF, IRBuilder<> &B,
FunctionCallee Fsincos) {
DebugLoc DL = B.getCurrentDebugLocation();
Function *F = B.GetInsertBlock()->getParent();
B.SetInsertPointPastAllocas(F);
AllocaInst *Alloc = B.CreateAlloca(Arg->getType(), nullptr, "__sincos_");
if (Instruction *ArgInst = dyn_cast<Instruction>(Arg)) {
// If the argument is an instruction, it must dominate all uses so put our
// sincos call there. Otherwise, right after the allocas works well enough
// if it's an argument or constant.
B.SetInsertPoint(ArgInst->getParent(), ++ArgInst->getIterator());
// SetInsertPoint unwelcomely always tries to set the debug loc.
B.SetCurrentDebugLocation(DL);
}
Type *CosPtrTy = Fsincos.getFunctionType()->getParamType(1);
// The allocaInst allocates the memory in private address space. This need
// to be addrspacecasted to point to the address space of cos pointer type.
// In OpenCL 2.0 this is generic, while in 1.2 that is private.
Value *CastAlloc = B.CreateAddrSpaceCast(Alloc, CosPtrTy);
CallInst *SinCos = CreateCallEx2(B, Fsincos, Arg, CastAlloc);
// TODO: Is it worth trying to preserve the location for the cos calls for the
// load?
LoadInst *LoadCos = B.CreateLoad(Alloc->getAllocatedType(), Alloc);
return {SinCos, LoadCos, SinCos};
}
// fold sin, cos -> sincos.
bool AMDGPULibCalls::fold_sincos(FPMathOperator *FPOp, IRBuilder<> &B,
const FuncInfo &fInfo) {
assert(fInfo.getId() == AMDGPULibFunc::EI_SIN ||
fInfo.getId() == AMDGPULibFunc::EI_COS);
if ((getArgType(fInfo) != AMDGPULibFunc::F32 &&
getArgType(fInfo) != AMDGPULibFunc::F64) ||
fInfo.getPrefix() != AMDGPULibFunc::NOPFX)
return false;
bool const isSin = fInfo.getId() == AMDGPULibFunc::EI_SIN;
Value *CArgVal = FPOp->getOperand(0);
CallInst *CI = cast<CallInst>(FPOp);
Function *F = B.GetInsertBlock()->getParent();
Module *M = F->getParent();
// Merge the sin and cos. For OpenCL 2.0, there may only be a generic pointer
// implementation. Prefer the private form if available.
AMDGPULibFunc SinCosLibFuncPrivate(AMDGPULibFunc::EI_SINCOS, fInfo);
SinCosLibFuncPrivate.getLeads()[0].PtrKind =
AMDGPULibFunc::getEPtrKindFromAddrSpace(AMDGPUAS::PRIVATE_ADDRESS);
AMDGPULibFunc SinCosLibFuncGeneric(AMDGPULibFunc::EI_SINCOS, fInfo);
SinCosLibFuncGeneric.getLeads()[0].PtrKind =
AMDGPULibFunc::getEPtrKindFromAddrSpace(AMDGPUAS::FLAT_ADDRESS);
FunctionCallee FSinCosPrivate = getFunction(M, SinCosLibFuncPrivate);
FunctionCallee FSinCosGeneric = getFunction(M, SinCosLibFuncGeneric);
FunctionCallee FSinCos = FSinCosPrivate ? FSinCosPrivate : FSinCosGeneric;
if (!FSinCos)
return false;
SmallVector<CallInst *> SinCalls;
SmallVector<CallInst *> CosCalls;
SmallVector<CallInst *> SinCosCalls;
FuncInfo PartnerInfo(isSin ? AMDGPULibFunc::EI_COS : AMDGPULibFunc::EI_SIN,
fInfo);
const std::string PairName = PartnerInfo.mangle();
StringRef SinName = isSin ? CI->getCalledFunction()->getName() : PairName;
StringRef CosName = isSin ? PairName : CI->getCalledFunction()->getName();
const std::string SinCosPrivateName = SinCosLibFuncPrivate.mangle();
const std::string SinCosGenericName = SinCosLibFuncGeneric.mangle();
// Intersect the two sets of flags.
FastMathFlags FMF = FPOp->getFastMathFlags();
MDNode *FPMath = CI->getMetadata(LLVMContext::MD_fpmath);
SmallVector<DILocation *> MergeDbgLocs = {CI->getDebugLoc()};
for (User* U : CArgVal->users()) {
CallInst *XI = dyn_cast<CallInst>(U);
if (!XI || XI->getFunction() != F || XI->isNoBuiltin())
continue;
Function *UCallee = XI->getCalledFunction();
if (!UCallee)
continue;
bool Handled = true;
if (UCallee->getName() == SinName)
SinCalls.push_back(XI);
else if (UCallee->getName() == CosName)
CosCalls.push_back(XI);
else if (UCallee->getName() == SinCosPrivateName ||
UCallee->getName() == SinCosGenericName)
SinCosCalls.push_back(XI);
else
Handled = false;
if (Handled) {
MergeDbgLocs.push_back(XI->getDebugLoc());
auto *OtherOp = cast<FPMathOperator>(XI);
FMF &= OtherOp->getFastMathFlags();
FPMath = MDNode::getMostGenericFPMath(
FPMath, XI->getMetadata(LLVMContext::MD_fpmath));
}
}
if (SinCalls.empty() || CosCalls.empty())
return false;
B.setFastMathFlags(FMF);
B.setDefaultFPMathTag(FPMath);
DILocation *DbgLoc = DILocation::getMergedLocations(MergeDbgLocs);
B.SetCurrentDebugLocation(DbgLoc);
auto [Sin, Cos, SinCos] = insertSinCos(CArgVal, FMF, B, FSinCos);
auto replaceTrigInsts = [](ArrayRef<CallInst *> Calls, Value *Res) {
for (CallInst *C : Calls)
C->replaceAllUsesWith(Res);
// Leave the other dead instructions to avoid clobbering iterators.
};
replaceTrigInsts(SinCalls, Sin);
replaceTrigInsts(CosCalls, Cos);
replaceTrigInsts(SinCosCalls, SinCos);
// It's safe to delete the original now.
CI->eraseFromParent();
return true;
}
bool AMDGPULibCalls::evaluateScalarMathFunc(const FuncInfo &FInfo, double &Res0,
double &Res1, Constant *copr0,
Constant *copr1) {
// By default, opr0/opr1/opr3 holds values of float/double type.
// If they are not float/double, each function has to its
// operand separately.
double opr0 = 0.0, opr1 = 0.0;
ConstantFP *fpopr0 = dyn_cast_or_null<ConstantFP>(copr0);
ConstantFP *fpopr1 = dyn_cast_or_null<ConstantFP>(copr1);
if (fpopr0) {
opr0 = (getArgType(FInfo) == AMDGPULibFunc::F64)
? fpopr0->getValueAPF().convertToDouble()
: (double)fpopr0->getValueAPF().convertToFloat();
}
if (fpopr1) {
opr1 = (getArgType(FInfo) == AMDGPULibFunc::F64)
? fpopr1->getValueAPF().convertToDouble()
: (double)fpopr1->getValueAPF().convertToFloat();
}
switch (FInfo.getId()) {
default : return false;
case AMDGPULibFunc::EI_ACOS:
Res0 = acos(opr0);
return true;
case AMDGPULibFunc::EI_ACOSH:
// acosh(x) == log(x + sqrt(x*x - 1))
Res0 = log(opr0 + sqrt(opr0*opr0 - 1.0));
return true;
case AMDGPULibFunc::EI_ACOSPI:
Res0 = acos(opr0) / MATH_PI;
return true;
case AMDGPULibFunc::EI_ASIN:
Res0 = asin(opr0);
return true;
case AMDGPULibFunc::EI_ASINH:
// asinh(x) == log(x + sqrt(x*x + 1))
Res0 = log(opr0 + sqrt(opr0*opr0 + 1.0));
return true;
case AMDGPULibFunc::EI_ASINPI:
Res0 = asin(opr0) / MATH_PI;
return true;
case AMDGPULibFunc::EI_ATAN:
Res0 = atan(opr0);
return true;
case AMDGPULibFunc::EI_ATANH:
// atanh(x) == (log(x+1) - log(x-1))/2;
Res0 = (log(opr0 + 1.0) - log(opr0 - 1.0))/2.0;
return true;
case AMDGPULibFunc::EI_ATANPI:
Res0 = atan(opr0) / MATH_PI;
return true;
case AMDGPULibFunc::EI_CBRT:
Res0 = (opr0 < 0.0) ? -pow(-opr0, 1.0/3.0) : pow(opr0, 1.0/3.0);
return true;
case AMDGPULibFunc::EI_COS:
Res0 = cos(opr0);
return true;
case AMDGPULibFunc::EI_COSH:
Res0 = cosh(opr0);
return true;
case AMDGPULibFunc::EI_COSPI:
Res0 = cos(MATH_PI * opr0);
return true;
case AMDGPULibFunc::EI_EXP:
Res0 = exp(opr0);
return true;
case AMDGPULibFunc::EI_EXP2:
Res0 = pow(2.0, opr0);
return true;
case AMDGPULibFunc::EI_EXP10:
Res0 = pow(10.0, opr0);
return true;
case AMDGPULibFunc::EI_LOG:
Res0 = log(opr0);
return true;
case AMDGPULibFunc::EI_LOG2:
Res0 = log(opr0) / log(2.0);
return true;
case AMDGPULibFunc::EI_LOG10:
Res0 = log(opr0) / log(10.0);
return true;
case AMDGPULibFunc::EI_RSQRT:
Res0 = 1.0 / sqrt(opr0);
return true;
case AMDGPULibFunc::EI_SIN:
Res0 = sin(opr0);
return true;
case AMDGPULibFunc::EI_SINH:
Res0 = sinh(opr0);
return true;
case AMDGPULibFunc::EI_SINPI:
Res0 = sin(MATH_PI * opr0);
return true;
case AMDGPULibFunc::EI_TAN:
Res0 = tan(opr0);
return true;
case AMDGPULibFunc::EI_TANH:
Res0 = tanh(opr0);
return true;
case AMDGPULibFunc::EI_TANPI:
Res0 = tan(MATH_PI * opr0);
return true;
// two-arg functions
case AMDGPULibFunc::EI_POW:
case AMDGPULibFunc::EI_POWR:
Res0 = pow(opr0, opr1);
return true;
case AMDGPULibFunc::EI_POWN: {
if (ConstantInt *iopr1 = dyn_cast_or_null<ConstantInt>(copr1)) {
double val = (double)iopr1->getSExtValue();
Res0 = pow(opr0, val);
return true;
}
return false;
}
case AMDGPULibFunc::EI_ROOTN: {
if (ConstantInt *iopr1 = dyn_cast_or_null<ConstantInt>(copr1)) {
double val = (double)iopr1->getSExtValue();
Res0 = pow(opr0, 1.0 / val);
return true;
}
return false;
}
// with ptr arg
case AMDGPULibFunc::EI_SINCOS:
Res0 = sin(opr0);
Res1 = cos(opr0);
return true;
}
return false;
}
bool AMDGPULibCalls::evaluateCall(CallInst *aCI, const FuncInfo &FInfo) {
int numArgs = (int)aCI->arg_size();
if (numArgs > 3)
return false;
Constant *copr0 = nullptr;
Constant *copr1 = nullptr;
if (numArgs > 0) {
if ((copr0 = dyn_cast<Constant>(aCI->getArgOperand(0))) == nullptr)
return false;
}
if (numArgs > 1) {
if ((copr1 = dyn_cast<Constant>(aCI->getArgOperand(1))) == nullptr) {
if (FInfo.getId() != AMDGPULibFunc::EI_SINCOS)
return false;
}
}
// At this point, all arguments to aCI are constants.
// max vector size is 16, and sincos will generate two results.
double DVal0[16], DVal1[16];
int FuncVecSize = getVecSize(FInfo);
bool hasTwoResults = (FInfo.getId() == AMDGPULibFunc::EI_SINCOS);
if (FuncVecSize == 1) {
if (!evaluateScalarMathFunc(FInfo, DVal0[0], DVal1[0], copr0, copr1)) {
return false;
}
} else {
ConstantDataVector *CDV0 = dyn_cast_or_null<ConstantDataVector>(copr0);
ConstantDataVector *CDV1 = dyn_cast_or_null<ConstantDataVector>(copr1);
for (int i = 0; i < FuncVecSize; ++i) {
Constant *celt0 = CDV0 ? CDV0->getElementAsConstant(i) : nullptr;
Constant *celt1 = CDV1 ? CDV1->getElementAsConstant(i) : nullptr;
if (!evaluateScalarMathFunc(FInfo, DVal0[i], DVal1[i], celt0, celt1)) {
return false;
}
}
}
LLVMContext &context = aCI->getContext();
Constant *nval0, *nval1;
if (FuncVecSize == 1) {
nval0 = ConstantFP::get(aCI->getType(), DVal0[0]);
if (hasTwoResults)
nval1 = ConstantFP::get(aCI->getType(), DVal1[0]);
} else {
if (getArgType(FInfo) == AMDGPULibFunc::F32) {
SmallVector <float, 0> FVal0, FVal1;
for (int i = 0; i < FuncVecSize; ++i)
FVal0.push_back((float)DVal0[i]);
ArrayRef<float> tmp0(FVal0);
nval0 = ConstantDataVector::get(context, tmp0);
if (hasTwoResults) {
for (int i = 0; i < FuncVecSize; ++i)
FVal1.push_back((float)DVal1[i]);
ArrayRef<float> tmp1(FVal1);
nval1 = ConstantDataVector::get(context, tmp1);
}
} else {
ArrayRef<double> tmp0(DVal0);
nval0 = ConstantDataVector::get(context, tmp0);
if (hasTwoResults) {
ArrayRef<double> tmp1(DVal1);
nval1 = ConstantDataVector::get(context, tmp1);
}
}
}
if (hasTwoResults) {
// sincos
assert(FInfo.getId() == AMDGPULibFunc::EI_SINCOS &&
"math function with ptr arg not supported yet");
new StoreInst(nval1, aCI->getArgOperand(1), aCI->getIterator());
}
replaceCall(aCI, nval0);
return true;
}
PreservedAnalyses AMDGPUSimplifyLibCallsPass::run(Function &F,
FunctionAnalysisManager &AM) {
AMDGPULibCalls Simplifier;
Simplifier.initNativeFuncs();
Simplifier.initFunction(F, AM);
bool Changed = false;
LLVM_DEBUG(dbgs() << "AMDIC: process function ";
F.printAsOperand(dbgs(), false, F.getParent()); dbgs() << '\n';);
for (auto &BB : F) {
for (BasicBlock::iterator I = BB.begin(), E = BB.end(); I != E;) {
// Ignore non-calls.
CallInst *CI = dyn_cast<CallInst>(I);
++I;
if (CI) {
if (Simplifier.fold(CI))
Changed = true;
}
}
}
return Changed ? PreservedAnalyses::none() : PreservedAnalyses::all();
}
PreservedAnalyses AMDGPUUseNativeCallsPass::run(Function &F,
FunctionAnalysisManager &AM) {
if (UseNative.empty())
return PreservedAnalyses::all();
AMDGPULibCalls Simplifier;
Simplifier.initNativeFuncs();
Simplifier.initFunction(F, AM);
bool Changed = false;
for (auto &BB : F) {
for (BasicBlock::iterator I = BB.begin(), E = BB.end(); I != E;) {
// Ignore non-calls.
CallInst *CI = dyn_cast<CallInst>(I);
++I;
if (CI && Simplifier.useNative(CI))
Changed = true;
}
}
return Changed ? PreservedAnalyses::none() : PreservedAnalyses::all();
}