3564 lines
126 KiB
C++
3564 lines
126 KiB
C++
//===------ SimplifyLibCalls.cpp - Library calls simplifier ---------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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//
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// This file implements the library calls simplifier. It does not implement
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// any pass, but can't be used by other passes to do simplifications.
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//
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//===----------------------------------------------------------------------===//
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#include "llvm/Transforms/Utils/SimplifyLibCalls.h"
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#include "llvm/ADT/APSInt.h"
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#include "llvm/ADT/SmallString.h"
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#include "llvm/ADT/StringMap.h"
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#include "llvm/ADT/Triple.h"
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#include "llvm/Analysis/BlockFrequencyInfo.h"
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#include "llvm/Analysis/ConstantFolding.h"
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#include "llvm/Analysis/OptimizationRemarkEmitter.h"
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#include "llvm/Analysis/ProfileSummaryInfo.h"
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#include "llvm/Transforms/Utils/Local.h"
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#include "llvm/Analysis/ValueTracking.h"
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#include "llvm/Analysis/CaptureTracking.h"
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#include "llvm/Analysis/Loads.h"
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#include "llvm/IR/DataLayout.h"
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#include "llvm/IR/Function.h"
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#include "llvm/IR/IRBuilder.h"
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#include "llvm/IR/IntrinsicInst.h"
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#include "llvm/IR/Intrinsics.h"
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#include "llvm/IR/LLVMContext.h"
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#include "llvm/IR/Module.h"
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#include "llvm/IR/PatternMatch.h"
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#include "llvm/Support/CommandLine.h"
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#include "llvm/Support/KnownBits.h"
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#include "llvm/Support/MathExtras.h"
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#include "llvm/Transforms/Utils/BuildLibCalls.h"
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#include "llvm/Transforms/Utils/SizeOpts.h"
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using namespace llvm;
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using namespace PatternMatch;
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static cl::opt<bool>
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EnableUnsafeFPShrink("enable-double-float-shrink", cl::Hidden,
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cl::init(false),
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cl::desc("Enable unsafe double to float "
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"shrinking for math lib calls"));
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//===----------------------------------------------------------------------===//
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// Helper Functions
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//===----------------------------------------------------------------------===//
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static bool ignoreCallingConv(LibFunc Func) {
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return Func == LibFunc_abs || Func == LibFunc_labs ||
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Func == LibFunc_llabs || Func == LibFunc_strlen;
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}
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static bool isCallingConvCCompatible(CallInst *CI) {
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switch(CI->getCallingConv()) {
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default:
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return false;
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case llvm::CallingConv::C:
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return true;
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case llvm::CallingConv::ARM_APCS:
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case llvm::CallingConv::ARM_AAPCS:
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case llvm::CallingConv::ARM_AAPCS_VFP: {
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// The iOS ABI diverges from the standard in some cases, so for now don't
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// try to simplify those calls.
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if (Triple(CI->getModule()->getTargetTriple()).isiOS())
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return false;
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auto *FuncTy = CI->getFunctionType();
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if (!FuncTy->getReturnType()->isPointerTy() &&
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!FuncTy->getReturnType()->isIntegerTy() &&
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!FuncTy->getReturnType()->isVoidTy())
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return false;
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for (auto Param : FuncTy->params()) {
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if (!Param->isPointerTy() && !Param->isIntegerTy())
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return false;
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}
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return true;
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}
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}
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return false;
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}
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/// Return true if it is only used in equality comparisons with With.
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static bool isOnlyUsedInEqualityComparison(Value *V, Value *With) {
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for (User *U : V->users()) {
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if (ICmpInst *IC = dyn_cast<ICmpInst>(U))
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if (IC->isEquality() && IC->getOperand(1) == With)
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continue;
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// Unknown instruction.
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return false;
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}
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return true;
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}
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static bool callHasFloatingPointArgument(const CallInst *CI) {
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return any_of(CI->operands(), [](const Use &OI) {
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return OI->getType()->isFloatingPointTy();
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});
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}
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static bool callHasFP128Argument(const CallInst *CI) {
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return any_of(CI->operands(), [](const Use &OI) {
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return OI->getType()->isFP128Ty();
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});
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}
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static Value *convertStrToNumber(CallInst *CI, StringRef &Str, int64_t Base) {
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if (Base < 2 || Base > 36)
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// handle special zero base
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if (Base != 0)
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return nullptr;
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char *End;
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std::string nptr = Str.str();
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errno = 0;
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long long int Result = strtoll(nptr.c_str(), &End, Base);
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if (errno)
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return nullptr;
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// if we assume all possible target locales are ASCII supersets,
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// then if strtoll successfully parses a number on the host,
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// it will also successfully parse the same way on the target
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if (*End != '\0')
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return nullptr;
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if (!isIntN(CI->getType()->getPrimitiveSizeInBits(), Result))
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return nullptr;
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return ConstantInt::get(CI->getType(), Result);
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}
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static bool isOnlyUsedInComparisonWithZero(Value *V) {
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for (User *U : V->users()) {
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if (ICmpInst *IC = dyn_cast<ICmpInst>(U))
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if (Constant *C = dyn_cast<Constant>(IC->getOperand(1)))
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if (C->isNullValue())
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continue;
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// Unknown instruction.
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return false;
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}
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return true;
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}
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static bool canTransformToMemCmp(CallInst *CI, Value *Str, uint64_t Len,
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const DataLayout &DL) {
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if (!isOnlyUsedInComparisonWithZero(CI))
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return false;
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if (!isDereferenceableAndAlignedPointer(Str, Align(1), APInt(64, Len), DL))
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return false;
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if (CI->getFunction()->hasFnAttribute(Attribute::SanitizeMemory))
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return false;
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return true;
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}
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static void annotateDereferenceableBytes(CallInst *CI,
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ArrayRef<unsigned> ArgNos,
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uint64_t DereferenceableBytes) {
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const Function *F = CI->getCaller();
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if (!F)
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return;
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for (unsigned ArgNo : ArgNos) {
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uint64_t DerefBytes = DereferenceableBytes;
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unsigned AS = CI->getArgOperand(ArgNo)->getType()->getPointerAddressSpace();
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if (!llvm::NullPointerIsDefined(F, AS) ||
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CI->paramHasAttr(ArgNo, Attribute::NonNull))
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DerefBytes = std::max(CI->getDereferenceableOrNullBytes(
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ArgNo + AttributeList::FirstArgIndex),
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DereferenceableBytes);
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if (CI->getDereferenceableBytes(ArgNo + AttributeList::FirstArgIndex) <
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DerefBytes) {
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CI->removeParamAttr(ArgNo, Attribute::Dereferenceable);
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if (!llvm::NullPointerIsDefined(F, AS) ||
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CI->paramHasAttr(ArgNo, Attribute::NonNull))
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CI->removeParamAttr(ArgNo, Attribute::DereferenceableOrNull);
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CI->addParamAttr(ArgNo, Attribute::getWithDereferenceableBytes(
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CI->getContext(), DerefBytes));
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}
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}
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}
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static void annotateNonNullBasedOnAccess(CallInst *CI,
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ArrayRef<unsigned> ArgNos) {
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Function *F = CI->getCaller();
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if (!F)
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return;
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for (unsigned ArgNo : ArgNos) {
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if (CI->paramHasAttr(ArgNo, Attribute::NonNull))
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continue;
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unsigned AS = CI->getArgOperand(ArgNo)->getType()->getPointerAddressSpace();
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if (llvm::NullPointerIsDefined(F, AS))
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continue;
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CI->addParamAttr(ArgNo, Attribute::NonNull);
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annotateDereferenceableBytes(CI, ArgNo, 1);
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}
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}
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static void annotateNonNullAndDereferenceable(CallInst *CI, ArrayRef<unsigned> ArgNos,
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Value *Size, const DataLayout &DL) {
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if (ConstantInt *LenC = dyn_cast<ConstantInt>(Size)) {
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annotateNonNullBasedOnAccess(CI, ArgNos);
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annotateDereferenceableBytes(CI, ArgNos, LenC->getZExtValue());
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} else if (isKnownNonZero(Size, DL)) {
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annotateNonNullBasedOnAccess(CI, ArgNos);
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const APInt *X, *Y;
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uint64_t DerefMin = 1;
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if (match(Size, m_Select(m_Value(), m_APInt(X), m_APInt(Y)))) {
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DerefMin = std::min(X->getZExtValue(), Y->getZExtValue());
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annotateDereferenceableBytes(CI, ArgNos, DerefMin);
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}
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}
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}
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//===----------------------------------------------------------------------===//
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// String and Memory Library Call Optimizations
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//===----------------------------------------------------------------------===//
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Value *LibCallSimplifier::optimizeStrCat(CallInst *CI, IRBuilderBase &B) {
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// Extract some information from the instruction
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Value *Dst = CI->getArgOperand(0);
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Value *Src = CI->getArgOperand(1);
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annotateNonNullBasedOnAccess(CI, {0, 1});
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// See if we can get the length of the input string.
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uint64_t Len = GetStringLength(Src);
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if (Len)
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annotateDereferenceableBytes(CI, 1, Len);
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else
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return nullptr;
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--Len; // Unbias length.
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// Handle the simple, do-nothing case: strcat(x, "") -> x
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if (Len == 0)
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return Dst;
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return emitStrLenMemCpy(Src, Dst, Len, B);
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}
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Value *LibCallSimplifier::emitStrLenMemCpy(Value *Src, Value *Dst, uint64_t Len,
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IRBuilderBase &B) {
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// We need to find the end of the destination string. That's where the
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// memory is to be moved to. We just generate a call to strlen.
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Value *DstLen = emitStrLen(Dst, B, DL, TLI);
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if (!DstLen)
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return nullptr;
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// Now that we have the destination's length, we must index into the
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// destination's pointer to get the actual memcpy destination (end of
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// the string .. we're concatenating).
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Value *CpyDst = B.CreateGEP(B.getInt8Ty(), Dst, DstLen, "endptr");
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// We have enough information to now generate the memcpy call to do the
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// concatenation for us. Make a memcpy to copy the nul byte with align = 1.
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B.CreateMemCpy(
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CpyDst, Align(1), Src, Align(1),
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ConstantInt::get(DL.getIntPtrType(Src->getContext()), Len + 1));
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return Dst;
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}
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Value *LibCallSimplifier::optimizeStrNCat(CallInst *CI, IRBuilderBase &B) {
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// Extract some information from the instruction.
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Value *Dst = CI->getArgOperand(0);
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Value *Src = CI->getArgOperand(1);
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Value *Size = CI->getArgOperand(2);
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uint64_t Len;
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annotateNonNullBasedOnAccess(CI, 0);
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if (isKnownNonZero(Size, DL))
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annotateNonNullBasedOnAccess(CI, 1);
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// We don't do anything if length is not constant.
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ConstantInt *LengthArg = dyn_cast<ConstantInt>(Size);
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if (LengthArg) {
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Len = LengthArg->getZExtValue();
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// strncat(x, c, 0) -> x
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if (!Len)
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return Dst;
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} else {
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return nullptr;
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}
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// See if we can get the length of the input string.
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uint64_t SrcLen = GetStringLength(Src);
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if (SrcLen) {
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annotateDereferenceableBytes(CI, 1, SrcLen);
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--SrcLen; // Unbias length.
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} else {
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return nullptr;
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}
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// strncat(x, "", c) -> x
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if (SrcLen == 0)
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return Dst;
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// We don't optimize this case.
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if (Len < SrcLen)
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return nullptr;
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// strncat(x, s, c) -> strcat(x, s)
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// s is constant so the strcat can be optimized further.
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return emitStrLenMemCpy(Src, Dst, SrcLen, B);
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}
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Value *LibCallSimplifier::optimizeStrChr(CallInst *CI, IRBuilderBase &B) {
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Function *Callee = CI->getCalledFunction();
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FunctionType *FT = Callee->getFunctionType();
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Value *SrcStr = CI->getArgOperand(0);
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annotateNonNullBasedOnAccess(CI, 0);
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// If the second operand is non-constant, see if we can compute the length
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// of the input string and turn this into memchr.
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ConstantInt *CharC = dyn_cast<ConstantInt>(CI->getArgOperand(1));
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if (!CharC) {
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uint64_t Len = GetStringLength(SrcStr);
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if (Len)
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annotateDereferenceableBytes(CI, 0, Len);
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else
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return nullptr;
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if (!FT->getParamType(1)->isIntegerTy(32)) // memchr needs i32.
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return nullptr;
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return emitMemChr(SrcStr, CI->getArgOperand(1), // include nul.
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ConstantInt::get(DL.getIntPtrType(CI->getContext()), Len),
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B, DL, TLI);
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}
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// Otherwise, the character is a constant, see if the first argument is
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// a string literal. If so, we can constant fold.
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StringRef Str;
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if (!getConstantStringInfo(SrcStr, Str)) {
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if (CharC->isZero()) // strchr(p, 0) -> p + strlen(p)
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if (Value *StrLen = emitStrLen(SrcStr, B, DL, TLI))
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return B.CreateGEP(B.getInt8Ty(), SrcStr, StrLen, "strchr");
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return nullptr;
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}
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// Compute the offset, make sure to handle the case when we're searching for
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// zero (a weird way to spell strlen).
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size_t I = (0xFF & CharC->getSExtValue()) == 0
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? Str.size()
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: Str.find(CharC->getSExtValue());
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if (I == StringRef::npos) // Didn't find the char. strchr returns null.
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return Constant::getNullValue(CI->getType());
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// strchr(s+n,c) -> gep(s+n+i,c)
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return B.CreateGEP(B.getInt8Ty(), SrcStr, B.getInt64(I), "strchr");
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}
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Value *LibCallSimplifier::optimizeStrRChr(CallInst *CI, IRBuilderBase &B) {
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Value *SrcStr = CI->getArgOperand(0);
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ConstantInt *CharC = dyn_cast<ConstantInt>(CI->getArgOperand(1));
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annotateNonNullBasedOnAccess(CI, 0);
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// Cannot fold anything if we're not looking for a constant.
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if (!CharC)
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return nullptr;
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StringRef Str;
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if (!getConstantStringInfo(SrcStr, Str)) {
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// strrchr(s, 0) -> strchr(s, 0)
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if (CharC->isZero())
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return emitStrChr(SrcStr, '\0', B, TLI);
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return nullptr;
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}
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// Compute the offset.
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size_t I = (0xFF & CharC->getSExtValue()) == 0
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? Str.size()
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: Str.rfind(CharC->getSExtValue());
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if (I == StringRef::npos) // Didn't find the char. Return null.
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return Constant::getNullValue(CI->getType());
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// strrchr(s+n,c) -> gep(s+n+i,c)
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return B.CreateGEP(B.getInt8Ty(), SrcStr, B.getInt64(I), "strrchr");
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}
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Value *LibCallSimplifier::optimizeStrCmp(CallInst *CI, IRBuilderBase &B) {
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Value *Str1P = CI->getArgOperand(0), *Str2P = CI->getArgOperand(1);
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if (Str1P == Str2P) // strcmp(x,x) -> 0
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return ConstantInt::get(CI->getType(), 0);
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StringRef Str1, Str2;
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bool HasStr1 = getConstantStringInfo(Str1P, Str1);
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bool HasStr2 = getConstantStringInfo(Str2P, Str2);
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// strcmp(x, y) -> cnst (if both x and y are constant strings)
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if (HasStr1 && HasStr2)
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return ConstantInt::get(CI->getType(), Str1.compare(Str2));
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if (HasStr1 && Str1.empty()) // strcmp("", x) -> -*x
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return B.CreateNeg(B.CreateZExt(
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B.CreateLoad(B.getInt8Ty(), Str2P, "strcmpload"), CI->getType()));
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if (HasStr2 && Str2.empty()) // strcmp(x,"") -> *x
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return B.CreateZExt(B.CreateLoad(B.getInt8Ty(), Str1P, "strcmpload"),
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CI->getType());
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// strcmp(P, "x") -> memcmp(P, "x", 2)
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uint64_t Len1 = GetStringLength(Str1P);
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if (Len1)
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annotateDereferenceableBytes(CI, 0, Len1);
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uint64_t Len2 = GetStringLength(Str2P);
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if (Len2)
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annotateDereferenceableBytes(CI, 1, Len2);
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if (Len1 && Len2) {
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return emitMemCmp(Str1P, Str2P,
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ConstantInt::get(DL.getIntPtrType(CI->getContext()),
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std::min(Len1, Len2)),
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B, DL, TLI);
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}
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// strcmp to memcmp
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if (!HasStr1 && HasStr2) {
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if (canTransformToMemCmp(CI, Str1P, Len2, DL))
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return emitMemCmp(
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Str1P, Str2P,
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ConstantInt::get(DL.getIntPtrType(CI->getContext()), Len2), B, DL,
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TLI);
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} else if (HasStr1 && !HasStr2) {
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if (canTransformToMemCmp(CI, Str2P, Len1, DL))
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return emitMemCmp(
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Str1P, Str2P,
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ConstantInt::get(DL.getIntPtrType(CI->getContext()), Len1), B, DL,
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TLI);
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}
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annotateNonNullBasedOnAccess(CI, {0, 1});
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return nullptr;
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}
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Value *LibCallSimplifier::optimizeStrNCmp(CallInst *CI, IRBuilderBase &B) {
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Value *Str1P = CI->getArgOperand(0);
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Value *Str2P = CI->getArgOperand(1);
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Value *Size = CI->getArgOperand(2);
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if (Str1P == Str2P) // strncmp(x,x,n) -> 0
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return ConstantInt::get(CI->getType(), 0);
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if (isKnownNonZero(Size, DL))
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annotateNonNullBasedOnAccess(CI, {0, 1});
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// Get the length argument if it is constant.
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uint64_t Length;
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if (ConstantInt *LengthArg = dyn_cast<ConstantInt>(Size))
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Length = LengthArg->getZExtValue();
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else
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return nullptr;
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if (Length == 0) // strncmp(x,y,0) -> 0
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return ConstantInt::get(CI->getType(), 0);
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if (Length == 1) // strncmp(x,y,1) -> memcmp(x,y,1)
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return emitMemCmp(Str1P, Str2P, Size, B, DL, TLI);
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StringRef Str1, Str2;
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bool HasStr1 = getConstantStringInfo(Str1P, Str1);
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bool HasStr2 = getConstantStringInfo(Str2P, Str2);
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// strncmp(x, y) -> cnst (if both x and y are constant strings)
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if (HasStr1 && HasStr2) {
|
|
StringRef SubStr1 = Str1.substr(0, Length);
|
|
StringRef SubStr2 = Str2.substr(0, Length);
|
|
return ConstantInt::get(CI->getType(), SubStr1.compare(SubStr2));
|
|
}
|
|
|
|
if (HasStr1 && Str1.empty()) // strncmp("", x, n) -> -*x
|
|
return B.CreateNeg(B.CreateZExt(
|
|
B.CreateLoad(B.getInt8Ty(), Str2P, "strcmpload"), CI->getType()));
|
|
|
|
if (HasStr2 && Str2.empty()) // strncmp(x, "", n) -> *x
|
|
return B.CreateZExt(B.CreateLoad(B.getInt8Ty(), Str1P, "strcmpload"),
|
|
CI->getType());
|
|
|
|
uint64_t Len1 = GetStringLength(Str1P);
|
|
if (Len1)
|
|
annotateDereferenceableBytes(CI, 0, Len1);
|
|
uint64_t Len2 = GetStringLength(Str2P);
|
|
if (Len2)
|
|
annotateDereferenceableBytes(CI, 1, Len2);
|
|
|
|
// strncmp to memcmp
|
|
if (!HasStr1 && HasStr2) {
|
|
Len2 = std::min(Len2, Length);
|
|
if (canTransformToMemCmp(CI, Str1P, Len2, DL))
|
|
return emitMemCmp(
|
|
Str1P, Str2P,
|
|
ConstantInt::get(DL.getIntPtrType(CI->getContext()), Len2), B, DL,
|
|
TLI);
|
|
} else if (HasStr1 && !HasStr2) {
|
|
Len1 = std::min(Len1, Length);
|
|
if (canTransformToMemCmp(CI, Str2P, Len1, DL))
|
|
return emitMemCmp(
|
|
Str1P, Str2P,
|
|
ConstantInt::get(DL.getIntPtrType(CI->getContext()), Len1), B, DL,
|
|
TLI);
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeStrNDup(CallInst *CI, IRBuilderBase &B) {
|
|
Value *Src = CI->getArgOperand(0);
|
|
ConstantInt *Size = dyn_cast<ConstantInt>(CI->getArgOperand(1));
|
|
uint64_t SrcLen = GetStringLength(Src);
|
|
if (SrcLen && Size) {
|
|
annotateDereferenceableBytes(CI, 0, SrcLen);
|
|
if (SrcLen <= Size->getZExtValue() + 1)
|
|
return emitStrDup(Src, B, TLI);
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeStrCpy(CallInst *CI, IRBuilderBase &B) {
|
|
Value *Dst = CI->getArgOperand(0), *Src = CI->getArgOperand(1);
|
|
if (Dst == Src) // strcpy(x,x) -> x
|
|
return Src;
|
|
|
|
annotateNonNullBasedOnAccess(CI, {0, 1});
|
|
// See if we can get the length of the input string.
|
|
uint64_t Len = GetStringLength(Src);
|
|
if (Len)
|
|
annotateDereferenceableBytes(CI, 1, Len);
|
|
else
|
|
return nullptr;
|
|
|
|
// We have enough information to now generate the memcpy call to do the
|
|
// copy for us. Make a memcpy to copy the nul byte with align = 1.
|
|
CallInst *NewCI =
|
|
B.CreateMemCpy(Dst, Align(1), Src, Align(1),
|
|
ConstantInt::get(DL.getIntPtrType(CI->getContext()), Len));
|
|
NewCI->setAttributes(CI->getAttributes());
|
|
NewCI->removeAttributes(AttributeList::ReturnIndex,
|
|
AttributeFuncs::typeIncompatible(NewCI->getType()));
|
|
return Dst;
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeStpCpy(CallInst *CI, IRBuilderBase &B) {
|
|
Function *Callee = CI->getCalledFunction();
|
|
Value *Dst = CI->getArgOperand(0), *Src = CI->getArgOperand(1);
|
|
if (Dst == Src) { // stpcpy(x,x) -> x+strlen(x)
|
|
Value *StrLen = emitStrLen(Src, B, DL, TLI);
|
|
return StrLen ? B.CreateInBoundsGEP(B.getInt8Ty(), Dst, StrLen) : nullptr;
|
|
}
|
|
|
|
// See if we can get the length of the input string.
|
|
uint64_t Len = GetStringLength(Src);
|
|
if (Len)
|
|
annotateDereferenceableBytes(CI, 1, Len);
|
|
else
|
|
return nullptr;
|
|
|
|
Type *PT = Callee->getFunctionType()->getParamType(0);
|
|
Value *LenV = ConstantInt::get(DL.getIntPtrType(PT), Len);
|
|
Value *DstEnd = B.CreateGEP(B.getInt8Ty(), Dst,
|
|
ConstantInt::get(DL.getIntPtrType(PT), Len - 1));
|
|
|
|
// We have enough information to now generate the memcpy call to do the
|
|
// copy for us. Make a memcpy to copy the nul byte with align = 1.
|
|
CallInst *NewCI = B.CreateMemCpy(Dst, Align(1), Src, Align(1), LenV);
|
|
NewCI->setAttributes(CI->getAttributes());
|
|
NewCI->removeAttributes(AttributeList::ReturnIndex,
|
|
AttributeFuncs::typeIncompatible(NewCI->getType()));
|
|
return DstEnd;
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeStrNCpy(CallInst *CI, IRBuilderBase &B) {
|
|
Function *Callee = CI->getCalledFunction();
|
|
Value *Dst = CI->getArgOperand(0);
|
|
Value *Src = CI->getArgOperand(1);
|
|
Value *Size = CI->getArgOperand(2);
|
|
annotateNonNullBasedOnAccess(CI, 0);
|
|
if (isKnownNonZero(Size, DL))
|
|
annotateNonNullBasedOnAccess(CI, 1);
|
|
|
|
uint64_t Len;
|
|
if (ConstantInt *LengthArg = dyn_cast<ConstantInt>(Size))
|
|
Len = LengthArg->getZExtValue();
|
|
else
|
|
return nullptr;
|
|
|
|
// strncpy(x, y, 0) -> x
|
|
if (Len == 0)
|
|
return Dst;
|
|
|
|
// See if we can get the length of the input string.
|
|
uint64_t SrcLen = GetStringLength(Src);
|
|
if (SrcLen) {
|
|
annotateDereferenceableBytes(CI, 1, SrcLen);
|
|
--SrcLen; // Unbias length.
|
|
} else {
|
|
return nullptr;
|
|
}
|
|
|
|
if (SrcLen == 0) {
|
|
// strncpy(x, "", y) -> memset(align 1 x, '\0', y)
|
|
CallInst *NewCI = B.CreateMemSet(Dst, B.getInt8('\0'), Size, Align(1));
|
|
AttrBuilder ArgAttrs(CI->getAttributes().getParamAttributes(0));
|
|
NewCI->setAttributes(NewCI->getAttributes().addParamAttributes(
|
|
CI->getContext(), 0, ArgAttrs));
|
|
return Dst;
|
|
}
|
|
|
|
// strncpy(a, "a", 4) - > memcpy(a, "a\0\0\0", 4)
|
|
if (Len > SrcLen + 1) {
|
|
if (Len <= 128) {
|
|
StringRef Str;
|
|
if (!getConstantStringInfo(Src, Str))
|
|
return nullptr;
|
|
std::string SrcStr = Str.str();
|
|
SrcStr.resize(Len, '\0');
|
|
Src = B.CreateGlobalString(SrcStr, "str");
|
|
} else {
|
|
return nullptr;
|
|
}
|
|
}
|
|
|
|
Type *PT = Callee->getFunctionType()->getParamType(0);
|
|
// strncpy(x, s, c) -> memcpy(align 1 x, align 1 s, c) [s and c are constant]
|
|
CallInst *NewCI = B.CreateMemCpy(Dst, Align(1), Src, Align(1),
|
|
ConstantInt::get(DL.getIntPtrType(PT), Len));
|
|
NewCI->setAttributes(CI->getAttributes());
|
|
NewCI->removeAttributes(AttributeList::ReturnIndex,
|
|
AttributeFuncs::typeIncompatible(NewCI->getType()));
|
|
return Dst;
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeStringLength(CallInst *CI, IRBuilderBase &B,
|
|
unsigned CharSize) {
|
|
Value *Src = CI->getArgOperand(0);
|
|
|
|
// Constant folding: strlen("xyz") -> 3
|
|
if (uint64_t Len = GetStringLength(Src, CharSize))
|
|
return ConstantInt::get(CI->getType(), Len - 1);
|
|
|
|
// If s is a constant pointer pointing to a string literal, we can fold
|
|
// strlen(s + x) to strlen(s) - x, when x is known to be in the range
|
|
// [0, strlen(s)] or the string has a single null terminator '\0' at the end.
|
|
// We only try to simplify strlen when the pointer s points to an array
|
|
// of i8. Otherwise, we would need to scale the offset x before doing the
|
|
// subtraction. This will make the optimization more complex, and it's not
|
|
// very useful because calling strlen for a pointer of other types is
|
|
// very uncommon.
|
|
if (GEPOperator *GEP = dyn_cast<GEPOperator>(Src)) {
|
|
if (!isGEPBasedOnPointerToString(GEP, CharSize))
|
|
return nullptr;
|
|
|
|
ConstantDataArraySlice Slice;
|
|
if (getConstantDataArrayInfo(GEP->getOperand(0), Slice, CharSize)) {
|
|
uint64_t NullTermIdx;
|
|
if (Slice.Array == nullptr) {
|
|
NullTermIdx = 0;
|
|
} else {
|
|
NullTermIdx = ~((uint64_t)0);
|
|
for (uint64_t I = 0, E = Slice.Length; I < E; ++I) {
|
|
if (Slice.Array->getElementAsInteger(I + Slice.Offset) == 0) {
|
|
NullTermIdx = I;
|
|
break;
|
|
}
|
|
}
|
|
// If the string does not have '\0', leave it to strlen to compute
|
|
// its length.
|
|
if (NullTermIdx == ~((uint64_t)0))
|
|
return nullptr;
|
|
}
|
|
|
|
Value *Offset = GEP->getOperand(2);
|
|
KnownBits Known = computeKnownBits(Offset, DL, 0, nullptr, CI, nullptr);
|
|
Known.Zero.flipAllBits();
|
|
uint64_t ArrSize =
|
|
cast<ArrayType>(GEP->getSourceElementType())->getNumElements();
|
|
|
|
// KnownZero's bits are flipped, so zeros in KnownZero now represent
|
|
// bits known to be zeros in Offset, and ones in KnowZero represent
|
|
// bits unknown in Offset. Therefore, Offset is known to be in range
|
|
// [0, NullTermIdx] when the flipped KnownZero is non-negative and
|
|
// unsigned-less-than NullTermIdx.
|
|
//
|
|
// If Offset is not provably in the range [0, NullTermIdx], we can still
|
|
// optimize if we can prove that the program has undefined behavior when
|
|
// Offset is outside that range. That is the case when GEP->getOperand(0)
|
|
// is a pointer to an object whose memory extent is NullTermIdx+1.
|
|
if ((Known.Zero.isNonNegative() && Known.Zero.ule(NullTermIdx)) ||
|
|
(GEP->isInBounds() && isa<GlobalVariable>(GEP->getOperand(0)) &&
|
|
NullTermIdx == ArrSize - 1)) {
|
|
Offset = B.CreateSExtOrTrunc(Offset, CI->getType());
|
|
return B.CreateSub(ConstantInt::get(CI->getType(), NullTermIdx),
|
|
Offset);
|
|
}
|
|
}
|
|
}
|
|
|
|
// strlen(x?"foo":"bars") --> x ? 3 : 4
|
|
if (SelectInst *SI = dyn_cast<SelectInst>(Src)) {
|
|
uint64_t LenTrue = GetStringLength(SI->getTrueValue(), CharSize);
|
|
uint64_t LenFalse = GetStringLength(SI->getFalseValue(), CharSize);
|
|
if (LenTrue && LenFalse) {
|
|
ORE.emit([&]() {
|
|
return OptimizationRemark("instcombine", "simplify-libcalls", CI)
|
|
<< "folded strlen(select) to select of constants";
|
|
});
|
|
return B.CreateSelect(SI->getCondition(),
|
|
ConstantInt::get(CI->getType(), LenTrue - 1),
|
|
ConstantInt::get(CI->getType(), LenFalse - 1));
|
|
}
|
|
}
|
|
|
|
// strlen(x) != 0 --> *x != 0
|
|
// strlen(x) == 0 --> *x == 0
|
|
if (isOnlyUsedInZeroEqualityComparison(CI))
|
|
return B.CreateZExt(B.CreateLoad(B.getIntNTy(CharSize), Src, "strlenfirst"),
|
|
CI->getType());
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeStrLen(CallInst *CI, IRBuilderBase &B) {
|
|
if (Value *V = optimizeStringLength(CI, B, 8))
|
|
return V;
|
|
annotateNonNullBasedOnAccess(CI, 0);
|
|
return nullptr;
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeWcslen(CallInst *CI, IRBuilderBase &B) {
|
|
Module &M = *CI->getModule();
|
|
unsigned WCharSize = TLI->getWCharSize(M) * 8;
|
|
// We cannot perform this optimization without wchar_size metadata.
|
|
if (WCharSize == 0)
|
|
return nullptr;
|
|
|
|
return optimizeStringLength(CI, B, WCharSize);
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeStrPBrk(CallInst *CI, IRBuilderBase &B) {
|
|
StringRef S1, S2;
|
|
bool HasS1 = getConstantStringInfo(CI->getArgOperand(0), S1);
|
|
bool HasS2 = getConstantStringInfo(CI->getArgOperand(1), S2);
|
|
|
|
// strpbrk(s, "") -> nullptr
|
|
// strpbrk("", s) -> nullptr
|
|
if ((HasS1 && S1.empty()) || (HasS2 && S2.empty()))
|
|
return Constant::getNullValue(CI->getType());
|
|
|
|
// Constant folding.
|
|
if (HasS1 && HasS2) {
|
|
size_t I = S1.find_first_of(S2);
|
|
if (I == StringRef::npos) // No match.
|
|
return Constant::getNullValue(CI->getType());
|
|
|
|
return B.CreateGEP(B.getInt8Ty(), CI->getArgOperand(0), B.getInt64(I),
|
|
"strpbrk");
|
|
}
|
|
|
|
// strpbrk(s, "a") -> strchr(s, 'a')
|
|
if (HasS2 && S2.size() == 1)
|
|
return emitStrChr(CI->getArgOperand(0), S2[0], B, TLI);
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeStrTo(CallInst *CI, IRBuilderBase &B) {
|
|
Value *EndPtr = CI->getArgOperand(1);
|
|
if (isa<ConstantPointerNull>(EndPtr)) {
|
|
// With a null EndPtr, this function won't capture the main argument.
|
|
// It would be readonly too, except that it still may write to errno.
|
|
CI->addParamAttr(0, Attribute::NoCapture);
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeStrSpn(CallInst *CI, IRBuilderBase &B) {
|
|
StringRef S1, S2;
|
|
bool HasS1 = getConstantStringInfo(CI->getArgOperand(0), S1);
|
|
bool HasS2 = getConstantStringInfo(CI->getArgOperand(1), S2);
|
|
|
|
// strspn(s, "") -> 0
|
|
// strspn("", s) -> 0
|
|
if ((HasS1 && S1.empty()) || (HasS2 && S2.empty()))
|
|
return Constant::getNullValue(CI->getType());
|
|
|
|
// Constant folding.
|
|
if (HasS1 && HasS2) {
|
|
size_t Pos = S1.find_first_not_of(S2);
|
|
if (Pos == StringRef::npos)
|
|
Pos = S1.size();
|
|
return ConstantInt::get(CI->getType(), Pos);
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeStrCSpn(CallInst *CI, IRBuilderBase &B) {
|
|
StringRef S1, S2;
|
|
bool HasS1 = getConstantStringInfo(CI->getArgOperand(0), S1);
|
|
bool HasS2 = getConstantStringInfo(CI->getArgOperand(1), S2);
|
|
|
|
// strcspn("", s) -> 0
|
|
if (HasS1 && S1.empty())
|
|
return Constant::getNullValue(CI->getType());
|
|
|
|
// Constant folding.
|
|
if (HasS1 && HasS2) {
|
|
size_t Pos = S1.find_first_of(S2);
|
|
if (Pos == StringRef::npos)
|
|
Pos = S1.size();
|
|
return ConstantInt::get(CI->getType(), Pos);
|
|
}
|
|
|
|
// strcspn(s, "") -> strlen(s)
|
|
if (HasS2 && S2.empty())
|
|
return emitStrLen(CI->getArgOperand(0), B, DL, TLI);
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeStrStr(CallInst *CI, IRBuilderBase &B) {
|
|
// fold strstr(x, x) -> x.
|
|
if (CI->getArgOperand(0) == CI->getArgOperand(1))
|
|
return B.CreateBitCast(CI->getArgOperand(0), CI->getType());
|
|
|
|
// fold strstr(a, b) == a -> strncmp(a, b, strlen(b)) == 0
|
|
if (isOnlyUsedInEqualityComparison(CI, CI->getArgOperand(0))) {
|
|
Value *StrLen = emitStrLen(CI->getArgOperand(1), B, DL, TLI);
|
|
if (!StrLen)
|
|
return nullptr;
|
|
Value *StrNCmp = emitStrNCmp(CI->getArgOperand(0), CI->getArgOperand(1),
|
|
StrLen, B, DL, TLI);
|
|
if (!StrNCmp)
|
|
return nullptr;
|
|
for (auto UI = CI->user_begin(), UE = CI->user_end(); UI != UE;) {
|
|
ICmpInst *Old = cast<ICmpInst>(*UI++);
|
|
Value *Cmp =
|
|
B.CreateICmp(Old->getPredicate(), StrNCmp,
|
|
ConstantInt::getNullValue(StrNCmp->getType()), "cmp");
|
|
replaceAllUsesWith(Old, Cmp);
|
|
}
|
|
return CI;
|
|
}
|
|
|
|
// See if either input string is a constant string.
|
|
StringRef SearchStr, ToFindStr;
|
|
bool HasStr1 = getConstantStringInfo(CI->getArgOperand(0), SearchStr);
|
|
bool HasStr2 = getConstantStringInfo(CI->getArgOperand(1), ToFindStr);
|
|
|
|
// fold strstr(x, "") -> x.
|
|
if (HasStr2 && ToFindStr.empty())
|
|
return B.CreateBitCast(CI->getArgOperand(0), CI->getType());
|
|
|
|
// If both strings are known, constant fold it.
|
|
if (HasStr1 && HasStr2) {
|
|
size_t Offset = SearchStr.find(ToFindStr);
|
|
|
|
if (Offset == StringRef::npos) // strstr("foo", "bar") -> null
|
|
return Constant::getNullValue(CI->getType());
|
|
|
|
// strstr("abcd", "bc") -> gep((char*)"abcd", 1)
|
|
Value *Result = castToCStr(CI->getArgOperand(0), B);
|
|
Result =
|
|
B.CreateConstInBoundsGEP1_64(B.getInt8Ty(), Result, Offset, "strstr");
|
|
return B.CreateBitCast(Result, CI->getType());
|
|
}
|
|
|
|
// fold strstr(x, "y") -> strchr(x, 'y').
|
|
if (HasStr2 && ToFindStr.size() == 1) {
|
|
Value *StrChr = emitStrChr(CI->getArgOperand(0), ToFindStr[0], B, TLI);
|
|
return StrChr ? B.CreateBitCast(StrChr, CI->getType()) : nullptr;
|
|
}
|
|
|
|
annotateNonNullBasedOnAccess(CI, {0, 1});
|
|
return nullptr;
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeMemRChr(CallInst *CI, IRBuilderBase &B) {
|
|
if (isKnownNonZero(CI->getOperand(2), DL))
|
|
annotateNonNullBasedOnAccess(CI, 0);
|
|
return nullptr;
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeMemChr(CallInst *CI, IRBuilderBase &B) {
|
|
Value *SrcStr = CI->getArgOperand(0);
|
|
Value *Size = CI->getArgOperand(2);
|
|
annotateNonNullAndDereferenceable(CI, 0, Size, DL);
|
|
ConstantInt *CharC = dyn_cast<ConstantInt>(CI->getArgOperand(1));
|
|
ConstantInt *LenC = dyn_cast<ConstantInt>(Size);
|
|
|
|
// memchr(x, y, 0) -> null
|
|
if (LenC) {
|
|
if (LenC->isZero())
|
|
return Constant::getNullValue(CI->getType());
|
|
} else {
|
|
// From now on we need at least constant length and string.
|
|
return nullptr;
|
|
}
|
|
|
|
StringRef Str;
|
|
if (!getConstantStringInfo(SrcStr, Str, 0, /*TrimAtNul=*/false))
|
|
return nullptr;
|
|
|
|
// Truncate the string to LenC. If Str is smaller than LenC we will still only
|
|
// scan the string, as reading past the end of it is undefined and we can just
|
|
// return null if we don't find the char.
|
|
Str = Str.substr(0, LenC->getZExtValue());
|
|
|
|
// If the char is variable but the input str and length are not we can turn
|
|
// this memchr call into a simple bit field test. Of course this only works
|
|
// when the return value is only checked against null.
|
|
//
|
|
// It would be really nice to reuse switch lowering here but we can't change
|
|
// the CFG at this point.
|
|
//
|
|
// memchr("\r\n", C, 2) != nullptr -> (1 << C & ((1 << '\r') | (1 << '\n')))
|
|
// != 0
|
|
// after bounds check.
|
|
if (!CharC && !Str.empty() && isOnlyUsedInZeroEqualityComparison(CI)) {
|
|
unsigned char Max =
|
|
*std::max_element(reinterpret_cast<const unsigned char *>(Str.begin()),
|
|
reinterpret_cast<const unsigned char *>(Str.end()));
|
|
|
|
// Make sure the bit field we're about to create fits in a register on the
|
|
// target.
|
|
// FIXME: On a 64 bit architecture this prevents us from using the
|
|
// interesting range of alpha ascii chars. We could do better by emitting
|
|
// two bitfields or shifting the range by 64 if no lower chars are used.
|
|
if (!DL.fitsInLegalInteger(Max + 1))
|
|
return nullptr;
|
|
|
|
// For the bit field use a power-of-2 type with at least 8 bits to avoid
|
|
// creating unnecessary illegal types.
|
|
unsigned char Width = NextPowerOf2(std::max((unsigned char)7, Max));
|
|
|
|
// Now build the bit field.
|
|
APInt Bitfield(Width, 0);
|
|
for (char C : Str)
|
|
Bitfield.setBit((unsigned char)C);
|
|
Value *BitfieldC = B.getInt(Bitfield);
|
|
|
|
// Adjust width of "C" to the bitfield width, then mask off the high bits.
|
|
Value *C = B.CreateZExtOrTrunc(CI->getArgOperand(1), BitfieldC->getType());
|
|
C = B.CreateAnd(C, B.getIntN(Width, 0xFF));
|
|
|
|
// First check that the bit field access is within bounds.
|
|
Value *Bounds = B.CreateICmp(ICmpInst::ICMP_ULT, C, B.getIntN(Width, Width),
|
|
"memchr.bounds");
|
|
|
|
// Create code that checks if the given bit is set in the field.
|
|
Value *Shl = B.CreateShl(B.getIntN(Width, 1ULL), C);
|
|
Value *Bits = B.CreateIsNotNull(B.CreateAnd(Shl, BitfieldC), "memchr.bits");
|
|
|
|
// Finally merge both checks and cast to pointer type. The inttoptr
|
|
// implicitly zexts the i1 to intptr type.
|
|
return B.CreateIntToPtr(B.CreateAnd(Bounds, Bits, "memchr"), CI->getType());
|
|
}
|
|
|
|
// Check if all arguments are constants. If so, we can constant fold.
|
|
if (!CharC)
|
|
return nullptr;
|
|
|
|
// Compute the offset.
|
|
size_t I = Str.find(CharC->getSExtValue() & 0xFF);
|
|
if (I == StringRef::npos) // Didn't find the char. memchr returns null.
|
|
return Constant::getNullValue(CI->getType());
|
|
|
|
// memchr(s+n,c,l) -> gep(s+n+i,c)
|
|
return B.CreateGEP(B.getInt8Ty(), SrcStr, B.getInt64(I), "memchr");
|
|
}
|
|
|
|
static Value *optimizeMemCmpConstantSize(CallInst *CI, Value *LHS, Value *RHS,
|
|
uint64_t Len, IRBuilderBase &B,
|
|
const DataLayout &DL) {
|
|
if (Len == 0) // memcmp(s1,s2,0) -> 0
|
|
return Constant::getNullValue(CI->getType());
|
|
|
|
// memcmp(S1,S2,1) -> *(unsigned char*)LHS - *(unsigned char*)RHS
|
|
if (Len == 1) {
|
|
Value *LHSV =
|
|
B.CreateZExt(B.CreateLoad(B.getInt8Ty(), castToCStr(LHS, B), "lhsc"),
|
|
CI->getType(), "lhsv");
|
|
Value *RHSV =
|
|
B.CreateZExt(B.CreateLoad(B.getInt8Ty(), castToCStr(RHS, B), "rhsc"),
|
|
CI->getType(), "rhsv");
|
|
return B.CreateSub(LHSV, RHSV, "chardiff");
|
|
}
|
|
|
|
// memcmp(S1,S2,N/8)==0 -> (*(intN_t*)S1 != *(intN_t*)S2)==0
|
|
// TODO: The case where both inputs are constants does not need to be limited
|
|
// to legal integers or equality comparison. See block below this.
|
|
if (DL.isLegalInteger(Len * 8) && isOnlyUsedInZeroEqualityComparison(CI)) {
|
|
IntegerType *IntType = IntegerType::get(CI->getContext(), Len * 8);
|
|
unsigned PrefAlignment = DL.getPrefTypeAlignment(IntType);
|
|
|
|
// First, see if we can fold either argument to a constant.
|
|
Value *LHSV = nullptr;
|
|
if (auto *LHSC = dyn_cast<Constant>(LHS)) {
|
|
LHSC = ConstantExpr::getBitCast(LHSC, IntType->getPointerTo());
|
|
LHSV = ConstantFoldLoadFromConstPtr(LHSC, IntType, DL);
|
|
}
|
|
Value *RHSV = nullptr;
|
|
if (auto *RHSC = dyn_cast<Constant>(RHS)) {
|
|
RHSC = ConstantExpr::getBitCast(RHSC, IntType->getPointerTo());
|
|
RHSV = ConstantFoldLoadFromConstPtr(RHSC, IntType, DL);
|
|
}
|
|
|
|
// Don't generate unaligned loads. If either source is constant data,
|
|
// alignment doesn't matter for that source because there is no load.
|
|
if ((LHSV || getKnownAlignment(LHS, DL, CI) >= PrefAlignment) &&
|
|
(RHSV || getKnownAlignment(RHS, DL, CI) >= PrefAlignment)) {
|
|
if (!LHSV) {
|
|
Type *LHSPtrTy =
|
|
IntType->getPointerTo(LHS->getType()->getPointerAddressSpace());
|
|
LHSV = B.CreateLoad(IntType, B.CreateBitCast(LHS, LHSPtrTy), "lhsv");
|
|
}
|
|
if (!RHSV) {
|
|
Type *RHSPtrTy =
|
|
IntType->getPointerTo(RHS->getType()->getPointerAddressSpace());
|
|
RHSV = B.CreateLoad(IntType, B.CreateBitCast(RHS, RHSPtrTy), "rhsv");
|
|
}
|
|
return B.CreateZExt(B.CreateICmpNE(LHSV, RHSV), CI->getType(), "memcmp");
|
|
}
|
|
}
|
|
|
|
// Constant folding: memcmp(x, y, Len) -> constant (all arguments are const).
|
|
// TODO: This is limited to i8 arrays.
|
|
StringRef LHSStr, RHSStr;
|
|
if (getConstantStringInfo(LHS, LHSStr) &&
|
|
getConstantStringInfo(RHS, RHSStr)) {
|
|
// Make sure we're not reading out-of-bounds memory.
|
|
if (Len > LHSStr.size() || Len > RHSStr.size())
|
|
return nullptr;
|
|
// Fold the memcmp and normalize the result. This way we get consistent
|
|
// results across multiple platforms.
|
|
uint64_t Ret = 0;
|
|
int Cmp = memcmp(LHSStr.data(), RHSStr.data(), Len);
|
|
if (Cmp < 0)
|
|
Ret = -1;
|
|
else if (Cmp > 0)
|
|
Ret = 1;
|
|
return ConstantInt::get(CI->getType(), Ret);
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
// Most simplifications for memcmp also apply to bcmp.
|
|
Value *LibCallSimplifier::optimizeMemCmpBCmpCommon(CallInst *CI,
|
|
IRBuilderBase &B) {
|
|
Value *LHS = CI->getArgOperand(0), *RHS = CI->getArgOperand(1);
|
|
Value *Size = CI->getArgOperand(2);
|
|
|
|
if (LHS == RHS) // memcmp(s,s,x) -> 0
|
|
return Constant::getNullValue(CI->getType());
|
|
|
|
annotateNonNullAndDereferenceable(CI, {0, 1}, Size, DL);
|
|
// Handle constant lengths.
|
|
ConstantInt *LenC = dyn_cast<ConstantInt>(Size);
|
|
if (!LenC)
|
|
return nullptr;
|
|
|
|
// memcmp(d,s,0) -> 0
|
|
if (LenC->getZExtValue() == 0)
|
|
return Constant::getNullValue(CI->getType());
|
|
|
|
if (Value *Res =
|
|
optimizeMemCmpConstantSize(CI, LHS, RHS, LenC->getZExtValue(), B, DL))
|
|
return Res;
|
|
return nullptr;
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeMemCmp(CallInst *CI, IRBuilderBase &B) {
|
|
if (Value *V = optimizeMemCmpBCmpCommon(CI, B))
|
|
return V;
|
|
|
|
// memcmp(x, y, Len) == 0 -> bcmp(x, y, Len) == 0
|
|
// bcmp can be more efficient than memcmp because it only has to know that
|
|
// there is a difference, not how different one is to the other.
|
|
if (TLI->has(LibFunc_bcmp) && isOnlyUsedInZeroEqualityComparison(CI)) {
|
|
Value *LHS = CI->getArgOperand(0);
|
|
Value *RHS = CI->getArgOperand(1);
|
|
Value *Size = CI->getArgOperand(2);
|
|
return emitBCmp(LHS, RHS, Size, B, DL, TLI);
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeBCmp(CallInst *CI, IRBuilderBase &B) {
|
|
return optimizeMemCmpBCmpCommon(CI, B);
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeMemCpy(CallInst *CI, IRBuilderBase &B) {
|
|
Value *Size = CI->getArgOperand(2);
|
|
annotateNonNullAndDereferenceable(CI, {0, 1}, Size, DL);
|
|
if (isa<IntrinsicInst>(CI))
|
|
return nullptr;
|
|
|
|
// memcpy(x, y, n) -> llvm.memcpy(align 1 x, align 1 y, n)
|
|
CallInst *NewCI = B.CreateMemCpy(CI->getArgOperand(0), Align(1),
|
|
CI->getArgOperand(1), Align(1), Size);
|
|
NewCI->setAttributes(CI->getAttributes());
|
|
NewCI->removeAttributes(AttributeList::ReturnIndex,
|
|
AttributeFuncs::typeIncompatible(NewCI->getType()));
|
|
return CI->getArgOperand(0);
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeMemCCpy(CallInst *CI, IRBuilderBase &B) {
|
|
Value *Dst = CI->getArgOperand(0);
|
|
Value *Src = CI->getArgOperand(1);
|
|
ConstantInt *StopChar = dyn_cast<ConstantInt>(CI->getArgOperand(2));
|
|
ConstantInt *N = dyn_cast<ConstantInt>(CI->getArgOperand(3));
|
|
StringRef SrcStr;
|
|
if (CI->use_empty() && Dst == Src)
|
|
return Dst;
|
|
// memccpy(d, s, c, 0) -> nullptr
|
|
if (N) {
|
|
if (N->isNullValue())
|
|
return Constant::getNullValue(CI->getType());
|
|
if (!getConstantStringInfo(Src, SrcStr, /*Offset=*/0,
|
|
/*TrimAtNul=*/false) ||
|
|
!StopChar)
|
|
return nullptr;
|
|
} else {
|
|
return nullptr;
|
|
}
|
|
|
|
// Wrap arg 'c' of type int to char
|
|
size_t Pos = SrcStr.find(StopChar->getSExtValue() & 0xFF);
|
|
if (Pos == StringRef::npos) {
|
|
if (N->getZExtValue() <= SrcStr.size()) {
|
|
B.CreateMemCpy(Dst, Align(1), Src, Align(1), CI->getArgOperand(3));
|
|
return Constant::getNullValue(CI->getType());
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
Value *NewN =
|
|
ConstantInt::get(N->getType(), std::min(uint64_t(Pos + 1), N->getZExtValue()));
|
|
// memccpy -> llvm.memcpy
|
|
B.CreateMemCpy(Dst, Align(1), Src, Align(1), NewN);
|
|
return Pos + 1 <= N->getZExtValue()
|
|
? B.CreateInBoundsGEP(B.getInt8Ty(), Dst, NewN)
|
|
: Constant::getNullValue(CI->getType());
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeMemPCpy(CallInst *CI, IRBuilderBase &B) {
|
|
Value *Dst = CI->getArgOperand(0);
|
|
Value *N = CI->getArgOperand(2);
|
|
// mempcpy(x, y, n) -> llvm.memcpy(align 1 x, align 1 y, n), x + n
|
|
CallInst *NewCI =
|
|
B.CreateMemCpy(Dst, Align(1), CI->getArgOperand(1), Align(1), N);
|
|
// Propagate attributes, but memcpy has no return value, so make sure that
|
|
// any return attributes are compliant.
|
|
// TODO: Attach return value attributes to the 1st operand to preserve them?
|
|
NewCI->setAttributes(CI->getAttributes());
|
|
NewCI->removeAttributes(AttributeList::ReturnIndex,
|
|
AttributeFuncs::typeIncompatible(NewCI->getType()));
|
|
return B.CreateInBoundsGEP(B.getInt8Ty(), Dst, N);
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeMemMove(CallInst *CI, IRBuilderBase &B) {
|
|
Value *Size = CI->getArgOperand(2);
|
|
annotateNonNullAndDereferenceable(CI, {0, 1}, Size, DL);
|
|
if (isa<IntrinsicInst>(CI))
|
|
return nullptr;
|
|
|
|
// memmove(x, y, n) -> llvm.memmove(align 1 x, align 1 y, n)
|
|
CallInst *NewCI = B.CreateMemMove(CI->getArgOperand(0), Align(1),
|
|
CI->getArgOperand(1), Align(1), Size);
|
|
NewCI->setAttributes(CI->getAttributes());
|
|
NewCI->removeAttributes(AttributeList::ReturnIndex,
|
|
AttributeFuncs::typeIncompatible(NewCI->getType()));
|
|
return CI->getArgOperand(0);
|
|
}
|
|
|
|
/// Fold memset[_chk](malloc(n), 0, n) --> calloc(1, n).
|
|
Value *LibCallSimplifier::foldMallocMemset(CallInst *Memset, IRBuilderBase &B) {
|
|
// This has to be a memset of zeros (bzero).
|
|
auto *FillValue = dyn_cast<ConstantInt>(Memset->getArgOperand(1));
|
|
if (!FillValue || FillValue->getZExtValue() != 0)
|
|
return nullptr;
|
|
|
|
// TODO: We should handle the case where the malloc has more than one use.
|
|
// This is necessary to optimize common patterns such as when the result of
|
|
// the malloc is checked against null or when a memset intrinsic is used in
|
|
// place of a memset library call.
|
|
auto *Malloc = dyn_cast<CallInst>(Memset->getArgOperand(0));
|
|
if (!Malloc || !Malloc->hasOneUse())
|
|
return nullptr;
|
|
|
|
// Is the inner call really malloc()?
|
|
Function *InnerCallee = Malloc->getCalledFunction();
|
|
if (!InnerCallee)
|
|
return nullptr;
|
|
|
|
LibFunc Func;
|
|
if (!TLI->getLibFunc(*InnerCallee, Func) || !TLI->has(Func) ||
|
|
Func != LibFunc_malloc)
|
|
return nullptr;
|
|
|
|
// The memset must cover the same number of bytes that are malloc'd.
|
|
if (Memset->getArgOperand(2) != Malloc->getArgOperand(0))
|
|
return nullptr;
|
|
|
|
// Replace the malloc with a calloc. We need the data layout to know what the
|
|
// actual size of a 'size_t' parameter is.
|
|
B.SetInsertPoint(Malloc->getParent(), ++Malloc->getIterator());
|
|
const DataLayout &DL = Malloc->getModule()->getDataLayout();
|
|
IntegerType *SizeType = DL.getIntPtrType(B.GetInsertBlock()->getContext());
|
|
if (Value *Calloc = emitCalloc(ConstantInt::get(SizeType, 1),
|
|
Malloc->getArgOperand(0),
|
|
Malloc->getAttributes(), B, *TLI)) {
|
|
substituteInParent(Malloc, Calloc);
|
|
return Calloc;
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeMemSet(CallInst *CI, IRBuilderBase &B) {
|
|
Value *Size = CI->getArgOperand(2);
|
|
annotateNonNullAndDereferenceable(CI, 0, Size, DL);
|
|
if (isa<IntrinsicInst>(CI))
|
|
return nullptr;
|
|
|
|
if (auto *Calloc = foldMallocMemset(CI, B))
|
|
return Calloc;
|
|
|
|
// memset(p, v, n) -> llvm.memset(align 1 p, v, n)
|
|
Value *Val = B.CreateIntCast(CI->getArgOperand(1), B.getInt8Ty(), false);
|
|
CallInst *NewCI = B.CreateMemSet(CI->getArgOperand(0), Val, Size, Align(1));
|
|
NewCI->setAttributes(CI->getAttributes());
|
|
NewCI->removeAttributes(AttributeList::ReturnIndex,
|
|
AttributeFuncs::typeIncompatible(NewCI->getType()));
|
|
return CI->getArgOperand(0);
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeRealloc(CallInst *CI, IRBuilderBase &B) {
|
|
if (isa<ConstantPointerNull>(CI->getArgOperand(0)))
|
|
return emitMalloc(CI->getArgOperand(1), B, DL, TLI);
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Math Library Optimizations
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
// Replace a libcall \p CI with a call to intrinsic \p IID
|
|
static Value *replaceUnaryCall(CallInst *CI, IRBuilderBase &B,
|
|
Intrinsic::ID IID) {
|
|
// Propagate fast-math flags from the existing call to the new call.
|
|
IRBuilderBase::FastMathFlagGuard Guard(B);
|
|
B.setFastMathFlags(CI->getFastMathFlags());
|
|
|
|
Module *M = CI->getModule();
|
|
Value *V = CI->getArgOperand(0);
|
|
Function *F = Intrinsic::getDeclaration(M, IID, CI->getType());
|
|
CallInst *NewCall = B.CreateCall(F, V);
|
|
NewCall->takeName(CI);
|
|
return NewCall;
|
|
}
|
|
|
|
/// Return a variant of Val with float type.
|
|
/// Currently this works in two cases: If Val is an FPExtension of a float
|
|
/// value to something bigger, simply return the operand.
|
|
/// If Val is a ConstantFP but can be converted to a float ConstantFP without
|
|
/// loss of precision do so.
|
|
static Value *valueHasFloatPrecision(Value *Val) {
|
|
if (FPExtInst *Cast = dyn_cast<FPExtInst>(Val)) {
|
|
Value *Op = Cast->getOperand(0);
|
|
if (Op->getType()->isFloatTy())
|
|
return Op;
|
|
}
|
|
if (ConstantFP *Const = dyn_cast<ConstantFP>(Val)) {
|
|
APFloat F = Const->getValueAPF();
|
|
bool losesInfo;
|
|
(void)F.convert(APFloat::IEEEsingle(), APFloat::rmNearestTiesToEven,
|
|
&losesInfo);
|
|
if (!losesInfo)
|
|
return ConstantFP::get(Const->getContext(), F);
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
/// Shrink double -> float functions.
|
|
static Value *optimizeDoubleFP(CallInst *CI, IRBuilderBase &B,
|
|
bool isBinary, bool isPrecise = false) {
|
|
Function *CalleeFn = CI->getCalledFunction();
|
|
if (!CI->getType()->isDoubleTy() || !CalleeFn)
|
|
return nullptr;
|
|
|
|
// If not all the uses of the function are converted to float, then bail out.
|
|
// This matters if the precision of the result is more important than the
|
|
// precision of the arguments.
|
|
if (isPrecise)
|
|
for (User *U : CI->users()) {
|
|
FPTruncInst *Cast = dyn_cast<FPTruncInst>(U);
|
|
if (!Cast || !Cast->getType()->isFloatTy())
|
|
return nullptr;
|
|
}
|
|
|
|
// If this is something like 'g((double) float)', convert to 'gf(float)'.
|
|
Value *V[2];
|
|
V[0] = valueHasFloatPrecision(CI->getArgOperand(0));
|
|
V[1] = isBinary ? valueHasFloatPrecision(CI->getArgOperand(1)) : nullptr;
|
|
if (!V[0] || (isBinary && !V[1]))
|
|
return nullptr;
|
|
|
|
// If call isn't an intrinsic, check that it isn't within a function with the
|
|
// same name as the float version of this call, otherwise the result is an
|
|
// infinite loop. For example, from MinGW-w64:
|
|
//
|
|
// float expf(float val) { return (float) exp((double) val); }
|
|
StringRef CalleeName = CalleeFn->getName();
|
|
bool IsIntrinsic = CalleeFn->isIntrinsic();
|
|
if (!IsIntrinsic) {
|
|
StringRef CallerName = CI->getFunction()->getName();
|
|
if (!CallerName.empty() && CallerName.back() == 'f' &&
|
|
CallerName.size() == (CalleeName.size() + 1) &&
|
|
CallerName.startswith(CalleeName))
|
|
return nullptr;
|
|
}
|
|
|
|
// Propagate the math semantics from the current function to the new function.
|
|
IRBuilderBase::FastMathFlagGuard Guard(B);
|
|
B.setFastMathFlags(CI->getFastMathFlags());
|
|
|
|
// g((double) float) -> (double) gf(float)
|
|
Value *R;
|
|
if (IsIntrinsic) {
|
|
Module *M = CI->getModule();
|
|
Intrinsic::ID IID = CalleeFn->getIntrinsicID();
|
|
Function *Fn = Intrinsic::getDeclaration(M, IID, B.getFloatTy());
|
|
R = isBinary ? B.CreateCall(Fn, V) : B.CreateCall(Fn, V[0]);
|
|
} else {
|
|
AttributeList CalleeAttrs = CalleeFn->getAttributes();
|
|
R = isBinary ? emitBinaryFloatFnCall(V[0], V[1], CalleeName, B, CalleeAttrs)
|
|
: emitUnaryFloatFnCall(V[0], CalleeName, B, CalleeAttrs);
|
|
}
|
|
return B.CreateFPExt(R, B.getDoubleTy());
|
|
}
|
|
|
|
/// Shrink double -> float for unary functions.
|
|
static Value *optimizeUnaryDoubleFP(CallInst *CI, IRBuilderBase &B,
|
|
bool isPrecise = false) {
|
|
return optimizeDoubleFP(CI, B, false, isPrecise);
|
|
}
|
|
|
|
/// Shrink double -> float for binary functions.
|
|
static Value *optimizeBinaryDoubleFP(CallInst *CI, IRBuilderBase &B,
|
|
bool isPrecise = false) {
|
|
return optimizeDoubleFP(CI, B, true, isPrecise);
|
|
}
|
|
|
|
// cabs(z) -> sqrt((creal(z)*creal(z)) + (cimag(z)*cimag(z)))
|
|
Value *LibCallSimplifier::optimizeCAbs(CallInst *CI, IRBuilderBase &B) {
|
|
if (!CI->isFast())
|
|
return nullptr;
|
|
|
|
// Propagate fast-math flags from the existing call to new instructions.
|
|
IRBuilderBase::FastMathFlagGuard Guard(B);
|
|
B.setFastMathFlags(CI->getFastMathFlags());
|
|
|
|
Value *Real, *Imag;
|
|
if (CI->getNumArgOperands() == 1) {
|
|
Value *Op = CI->getArgOperand(0);
|
|
assert(Op->getType()->isArrayTy() && "Unexpected signature for cabs!");
|
|
Real = B.CreateExtractValue(Op, 0, "real");
|
|
Imag = B.CreateExtractValue(Op, 1, "imag");
|
|
} else {
|
|
assert(CI->getNumArgOperands() == 2 && "Unexpected signature for cabs!");
|
|
Real = CI->getArgOperand(0);
|
|
Imag = CI->getArgOperand(1);
|
|
}
|
|
|
|
Value *RealReal = B.CreateFMul(Real, Real);
|
|
Value *ImagImag = B.CreateFMul(Imag, Imag);
|
|
|
|
Function *FSqrt = Intrinsic::getDeclaration(CI->getModule(), Intrinsic::sqrt,
|
|
CI->getType());
|
|
return B.CreateCall(FSqrt, B.CreateFAdd(RealReal, ImagImag), "cabs");
|
|
}
|
|
|
|
static Value *optimizeTrigReflections(CallInst *Call, LibFunc Func,
|
|
IRBuilderBase &B) {
|
|
if (!isa<FPMathOperator>(Call))
|
|
return nullptr;
|
|
|
|
IRBuilderBase::FastMathFlagGuard Guard(B);
|
|
B.setFastMathFlags(Call->getFastMathFlags());
|
|
|
|
// TODO: Can this be shared to also handle LLVM intrinsics?
|
|
Value *X;
|
|
switch (Func) {
|
|
case LibFunc_sin:
|
|
case LibFunc_sinf:
|
|
case LibFunc_sinl:
|
|
case LibFunc_tan:
|
|
case LibFunc_tanf:
|
|
case LibFunc_tanl:
|
|
// sin(-X) --> -sin(X)
|
|
// tan(-X) --> -tan(X)
|
|
if (match(Call->getArgOperand(0), m_OneUse(m_FNeg(m_Value(X)))))
|
|
return B.CreateFNeg(B.CreateCall(Call->getCalledFunction(), X));
|
|
break;
|
|
case LibFunc_cos:
|
|
case LibFunc_cosf:
|
|
case LibFunc_cosl:
|
|
// cos(-X) --> cos(X)
|
|
if (match(Call->getArgOperand(0), m_FNeg(m_Value(X))))
|
|
return B.CreateCall(Call->getCalledFunction(), X, "cos");
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
static Value *getPow(Value *InnerChain[33], unsigned Exp, IRBuilderBase &B) {
|
|
// Multiplications calculated using Addition Chains.
|
|
// Refer: http://wwwhomes.uni-bielefeld.de/achim/addition_chain.html
|
|
|
|
assert(Exp != 0 && "Incorrect exponent 0 not handled");
|
|
|
|
if (InnerChain[Exp])
|
|
return InnerChain[Exp];
|
|
|
|
static const unsigned AddChain[33][2] = {
|
|
{0, 0}, // Unused.
|
|
{0, 0}, // Unused (base case = pow1).
|
|
{1, 1}, // Unused (pre-computed).
|
|
{1, 2}, {2, 2}, {2, 3}, {3, 3}, {2, 5}, {4, 4},
|
|
{1, 8}, {5, 5}, {1, 10}, {6, 6}, {4, 9}, {7, 7},
|
|
{3, 12}, {8, 8}, {8, 9}, {2, 16}, {1, 18}, {10, 10},
|
|
{6, 15}, {11, 11}, {3, 20}, {12, 12}, {8, 17}, {13, 13},
|
|
{3, 24}, {14, 14}, {4, 25}, {15, 15}, {3, 28}, {16, 16},
|
|
};
|
|
|
|
InnerChain[Exp] = B.CreateFMul(getPow(InnerChain, AddChain[Exp][0], B),
|
|
getPow(InnerChain, AddChain[Exp][1], B));
|
|
return InnerChain[Exp];
|
|
}
|
|
|
|
// Return a properly extended 32-bit integer if the operation is an itofp.
|
|
static Value *getIntToFPVal(Value *I2F, IRBuilderBase &B) {
|
|
if (isa<SIToFPInst>(I2F) || isa<UIToFPInst>(I2F)) {
|
|
Value *Op = cast<Instruction>(I2F)->getOperand(0);
|
|
// Make sure that the exponent fits inside an int32_t,
|
|
// thus avoiding any range issues that FP has not.
|
|
unsigned BitWidth = Op->getType()->getPrimitiveSizeInBits();
|
|
if (BitWidth < 32 ||
|
|
(BitWidth == 32 && isa<SIToFPInst>(I2F)))
|
|
return isa<SIToFPInst>(I2F) ? B.CreateSExt(Op, B.getInt32Ty())
|
|
: B.CreateZExt(Op, B.getInt32Ty());
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
/// Use exp{,2}(x * y) for pow(exp{,2}(x), y);
|
|
/// ldexp(1.0, x) for pow(2.0, itofp(x)); exp2(n * x) for pow(2.0 ** n, x);
|
|
/// exp10(x) for pow(10.0, x); exp2(log2(n) * x) for pow(n, x).
|
|
Value *LibCallSimplifier::replacePowWithExp(CallInst *Pow, IRBuilderBase &B) {
|
|
Value *Base = Pow->getArgOperand(0), *Expo = Pow->getArgOperand(1);
|
|
AttributeList Attrs; // Attributes are only meaningful on the original call
|
|
Module *Mod = Pow->getModule();
|
|
Type *Ty = Pow->getType();
|
|
bool Ignored;
|
|
|
|
// Evaluate special cases related to a nested function as the base.
|
|
|
|
// pow(exp(x), y) -> exp(x * y)
|
|
// pow(exp2(x), y) -> exp2(x * y)
|
|
// If exp{,2}() is used only once, it is better to fold two transcendental
|
|
// math functions into one. If used again, exp{,2}() would still have to be
|
|
// called with the original argument, then keep both original transcendental
|
|
// functions. However, this transformation is only safe with fully relaxed
|
|
// math semantics, since, besides rounding differences, it changes overflow
|
|
// and underflow behavior quite dramatically. For example:
|
|
// pow(exp(1000), 0.001) = pow(inf, 0.001) = inf
|
|
// Whereas:
|
|
// exp(1000 * 0.001) = exp(1)
|
|
// TODO: Loosen the requirement for fully relaxed math semantics.
|
|
// TODO: Handle exp10() when more targets have it available.
|
|
CallInst *BaseFn = dyn_cast<CallInst>(Base);
|
|
if (BaseFn && BaseFn->hasOneUse() && BaseFn->isFast() && Pow->isFast()) {
|
|
LibFunc LibFn;
|
|
|
|
Function *CalleeFn = BaseFn->getCalledFunction();
|
|
if (CalleeFn &&
|
|
TLI->getLibFunc(CalleeFn->getName(), LibFn) && TLI->has(LibFn)) {
|
|
StringRef ExpName;
|
|
Intrinsic::ID ID;
|
|
Value *ExpFn;
|
|
LibFunc LibFnFloat, LibFnDouble, LibFnLongDouble;
|
|
|
|
switch (LibFn) {
|
|
default:
|
|
return nullptr;
|
|
case LibFunc_expf: case LibFunc_exp: case LibFunc_expl:
|
|
ExpName = TLI->getName(LibFunc_exp);
|
|
ID = Intrinsic::exp;
|
|
LibFnFloat = LibFunc_expf;
|
|
LibFnDouble = LibFunc_exp;
|
|
LibFnLongDouble = LibFunc_expl;
|
|
break;
|
|
case LibFunc_exp2f: case LibFunc_exp2: case LibFunc_exp2l:
|
|
ExpName = TLI->getName(LibFunc_exp2);
|
|
ID = Intrinsic::exp2;
|
|
LibFnFloat = LibFunc_exp2f;
|
|
LibFnDouble = LibFunc_exp2;
|
|
LibFnLongDouble = LibFunc_exp2l;
|
|
break;
|
|
}
|
|
|
|
// Create new exp{,2}() with the product as its argument.
|
|
Value *FMul = B.CreateFMul(BaseFn->getArgOperand(0), Expo, "mul");
|
|
ExpFn = BaseFn->doesNotAccessMemory()
|
|
? B.CreateCall(Intrinsic::getDeclaration(Mod, ID, Ty),
|
|
FMul, ExpName)
|
|
: emitUnaryFloatFnCall(FMul, TLI, LibFnDouble, LibFnFloat,
|
|
LibFnLongDouble, B,
|
|
BaseFn->getAttributes());
|
|
|
|
// Since the new exp{,2}() is different from the original one, dead code
|
|
// elimination cannot be trusted to remove it, since it may have side
|
|
// effects (e.g., errno). When the only consumer for the original
|
|
// exp{,2}() is pow(), then it has to be explicitly erased.
|
|
substituteInParent(BaseFn, ExpFn);
|
|
return ExpFn;
|
|
}
|
|
}
|
|
|
|
// Evaluate special cases related to a constant base.
|
|
|
|
const APFloat *BaseF;
|
|
if (!match(Pow->getArgOperand(0), m_APFloat(BaseF)))
|
|
return nullptr;
|
|
|
|
// pow(2.0, itofp(x)) -> ldexp(1.0, x)
|
|
if (match(Base, m_SpecificFP(2.0)) &&
|
|
(isa<SIToFPInst>(Expo) || isa<UIToFPInst>(Expo)) &&
|
|
hasFloatFn(TLI, Ty, LibFunc_ldexp, LibFunc_ldexpf, LibFunc_ldexpl)) {
|
|
if (Value *ExpoI = getIntToFPVal(Expo, B))
|
|
return emitBinaryFloatFnCall(ConstantFP::get(Ty, 1.0), ExpoI, TLI,
|
|
LibFunc_ldexp, LibFunc_ldexpf, LibFunc_ldexpl,
|
|
B, Attrs);
|
|
}
|
|
|
|
// pow(2.0 ** n, x) -> exp2(n * x)
|
|
if (hasFloatFn(TLI, Ty, LibFunc_exp2, LibFunc_exp2f, LibFunc_exp2l)) {
|
|
APFloat BaseR = APFloat(1.0);
|
|
BaseR.convert(BaseF->getSemantics(), APFloat::rmTowardZero, &Ignored);
|
|
BaseR = BaseR / *BaseF;
|
|
bool IsInteger = BaseF->isInteger(), IsReciprocal = BaseR.isInteger();
|
|
const APFloat *NF = IsReciprocal ? &BaseR : BaseF;
|
|
APSInt NI(64, false);
|
|
if ((IsInteger || IsReciprocal) &&
|
|
NF->convertToInteger(NI, APFloat::rmTowardZero, &Ignored) ==
|
|
APFloat::opOK &&
|
|
NI > 1 && NI.isPowerOf2()) {
|
|
double N = NI.logBase2() * (IsReciprocal ? -1.0 : 1.0);
|
|
Value *FMul = B.CreateFMul(Expo, ConstantFP::get(Ty, N), "mul");
|
|
if (Pow->doesNotAccessMemory())
|
|
return B.CreateCall(Intrinsic::getDeclaration(Mod, Intrinsic::exp2, Ty),
|
|
FMul, "exp2");
|
|
else
|
|
return emitUnaryFloatFnCall(FMul, TLI, LibFunc_exp2, LibFunc_exp2f,
|
|
LibFunc_exp2l, B, Attrs);
|
|
}
|
|
}
|
|
|
|
// pow(10.0, x) -> exp10(x)
|
|
// TODO: There is no exp10() intrinsic yet, but some day there shall be one.
|
|
if (match(Base, m_SpecificFP(10.0)) &&
|
|
hasFloatFn(TLI, Ty, LibFunc_exp10, LibFunc_exp10f, LibFunc_exp10l))
|
|
return emitUnaryFloatFnCall(Expo, TLI, LibFunc_exp10, LibFunc_exp10f,
|
|
LibFunc_exp10l, B, Attrs);
|
|
|
|
// pow(x, y) -> exp2(log2(x) * y)
|
|
if (Pow->hasApproxFunc() && Pow->hasNoNaNs() && BaseF->isFiniteNonZero() &&
|
|
!BaseF->isNegative()) {
|
|
// pow(1, inf) is defined to be 1 but exp2(log2(1) * inf) evaluates to NaN.
|
|
// Luckily optimizePow has already handled the x == 1 case.
|
|
assert(!match(Base, m_FPOne()) &&
|
|
"pow(1.0, y) should have been simplified earlier!");
|
|
|
|
Value *Log = nullptr;
|
|
if (Ty->isFloatTy())
|
|
Log = ConstantFP::get(Ty, std::log2(BaseF->convertToFloat()));
|
|
else if (Ty->isDoubleTy())
|
|
Log = ConstantFP::get(Ty, std::log2(BaseF->convertToDouble()));
|
|
|
|
if (Log) {
|
|
Value *FMul = B.CreateFMul(Log, Expo, "mul");
|
|
if (Pow->doesNotAccessMemory())
|
|
return B.CreateCall(Intrinsic::getDeclaration(Mod, Intrinsic::exp2, Ty),
|
|
FMul, "exp2");
|
|
else if (hasFloatFn(TLI, Ty, LibFunc_exp2, LibFunc_exp2f, LibFunc_exp2l))
|
|
return emitUnaryFloatFnCall(FMul, TLI, LibFunc_exp2, LibFunc_exp2f,
|
|
LibFunc_exp2l, B, Attrs);
|
|
}
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
static Value *getSqrtCall(Value *V, AttributeList Attrs, bool NoErrno,
|
|
Module *M, IRBuilderBase &B,
|
|
const TargetLibraryInfo *TLI) {
|
|
// If errno is never set, then use the intrinsic for sqrt().
|
|
if (NoErrno) {
|
|
Function *SqrtFn =
|
|
Intrinsic::getDeclaration(M, Intrinsic::sqrt, V->getType());
|
|
return B.CreateCall(SqrtFn, V, "sqrt");
|
|
}
|
|
|
|
// Otherwise, use the libcall for sqrt().
|
|
if (hasFloatFn(TLI, V->getType(), LibFunc_sqrt, LibFunc_sqrtf, LibFunc_sqrtl))
|
|
// TODO: We also should check that the target can in fact lower the sqrt()
|
|
// libcall. We currently have no way to ask this question, so we ask if
|
|
// the target has a sqrt() libcall, which is not exactly the same.
|
|
return emitUnaryFloatFnCall(V, TLI, LibFunc_sqrt, LibFunc_sqrtf,
|
|
LibFunc_sqrtl, B, Attrs);
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
/// Use square root in place of pow(x, +/-0.5).
|
|
Value *LibCallSimplifier::replacePowWithSqrt(CallInst *Pow, IRBuilderBase &B) {
|
|
Value *Sqrt, *Base = Pow->getArgOperand(0), *Expo = Pow->getArgOperand(1);
|
|
AttributeList Attrs; // Attributes are only meaningful on the original call
|
|
Module *Mod = Pow->getModule();
|
|
Type *Ty = Pow->getType();
|
|
|
|
const APFloat *ExpoF;
|
|
if (!match(Expo, m_APFloat(ExpoF)) ||
|
|
(!ExpoF->isExactlyValue(0.5) && !ExpoF->isExactlyValue(-0.5)))
|
|
return nullptr;
|
|
|
|
// Converting pow(X, -0.5) to 1/sqrt(X) may introduce an extra rounding step,
|
|
// so that requires fast-math-flags (afn or reassoc).
|
|
if (ExpoF->isNegative() && (!Pow->hasApproxFunc() && !Pow->hasAllowReassoc()))
|
|
return nullptr;
|
|
|
|
// If we have a pow() library call (accesses memory) and we can't guarantee
|
|
// that the base is not an infinity, give up:
|
|
// pow(-Inf, 0.5) is optionally required to have a result of +Inf (not setting
|
|
// errno), but sqrt(-Inf) is required by various standards to set errno.
|
|
if (!Pow->doesNotAccessMemory() && !Pow->hasNoInfs() &&
|
|
!isKnownNeverInfinity(Base, TLI))
|
|
return nullptr;
|
|
|
|
Sqrt = getSqrtCall(Base, Attrs, Pow->doesNotAccessMemory(), Mod, B, TLI);
|
|
if (!Sqrt)
|
|
return nullptr;
|
|
|
|
// Handle signed zero base by expanding to fabs(sqrt(x)).
|
|
if (!Pow->hasNoSignedZeros()) {
|
|
Function *FAbsFn = Intrinsic::getDeclaration(Mod, Intrinsic::fabs, Ty);
|
|
Sqrt = B.CreateCall(FAbsFn, Sqrt, "abs");
|
|
}
|
|
|
|
// Handle non finite base by expanding to
|
|
// (x == -infinity ? +infinity : sqrt(x)).
|
|
if (!Pow->hasNoInfs()) {
|
|
Value *PosInf = ConstantFP::getInfinity(Ty),
|
|
*NegInf = ConstantFP::getInfinity(Ty, true);
|
|
Value *FCmp = B.CreateFCmpOEQ(Base, NegInf, "isinf");
|
|
Sqrt = B.CreateSelect(FCmp, PosInf, Sqrt);
|
|
}
|
|
|
|
// If the exponent is negative, then get the reciprocal.
|
|
if (ExpoF->isNegative())
|
|
Sqrt = B.CreateFDiv(ConstantFP::get(Ty, 1.0), Sqrt, "reciprocal");
|
|
|
|
return Sqrt;
|
|
}
|
|
|
|
static Value *createPowWithIntegerExponent(Value *Base, Value *Expo, Module *M,
|
|
IRBuilderBase &B) {
|
|
Value *Args[] = {Base, Expo};
|
|
Function *F = Intrinsic::getDeclaration(M, Intrinsic::powi, Base->getType());
|
|
return B.CreateCall(F, Args);
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizePow(CallInst *Pow, IRBuilderBase &B) {
|
|
Value *Base = Pow->getArgOperand(0);
|
|
Value *Expo = Pow->getArgOperand(1);
|
|
Function *Callee = Pow->getCalledFunction();
|
|
StringRef Name = Callee->getName();
|
|
Type *Ty = Pow->getType();
|
|
Module *M = Pow->getModule();
|
|
Value *Shrunk = nullptr;
|
|
bool AllowApprox = Pow->hasApproxFunc();
|
|
bool Ignored;
|
|
|
|
// Propagate the math semantics from the call to any created instructions.
|
|
IRBuilderBase::FastMathFlagGuard Guard(B);
|
|
B.setFastMathFlags(Pow->getFastMathFlags());
|
|
|
|
// Shrink pow() to powf() if the arguments are single precision,
|
|
// unless the result is expected to be double precision.
|
|
if (UnsafeFPShrink && Name == TLI->getName(LibFunc_pow) &&
|
|
hasFloatVersion(Name))
|
|
Shrunk = optimizeBinaryDoubleFP(Pow, B, true);
|
|
|
|
// Evaluate special cases related to the base.
|
|
|
|
// pow(1.0, x) -> 1.0
|
|
if (match(Base, m_FPOne()))
|
|
return Base;
|
|
|
|
if (Value *Exp = replacePowWithExp(Pow, B))
|
|
return Exp;
|
|
|
|
// Evaluate special cases related to the exponent.
|
|
|
|
// pow(x, -1.0) -> 1.0 / x
|
|
if (match(Expo, m_SpecificFP(-1.0)))
|
|
return B.CreateFDiv(ConstantFP::get(Ty, 1.0), Base, "reciprocal");
|
|
|
|
// pow(x, +/-0.0) -> 1.0
|
|
if (match(Expo, m_AnyZeroFP()))
|
|
return ConstantFP::get(Ty, 1.0);
|
|
|
|
// pow(x, 1.0) -> x
|
|
if (match(Expo, m_FPOne()))
|
|
return Base;
|
|
|
|
// pow(x, 2.0) -> x * x
|
|
if (match(Expo, m_SpecificFP(2.0)))
|
|
return B.CreateFMul(Base, Base, "square");
|
|
|
|
if (Value *Sqrt = replacePowWithSqrt(Pow, B))
|
|
return Sqrt;
|
|
|
|
// pow(x, n) -> x * x * x * ...
|
|
const APFloat *ExpoF;
|
|
if (AllowApprox && match(Expo, m_APFloat(ExpoF)) &&
|
|
!ExpoF->isExactlyValue(0.5) && !ExpoF->isExactlyValue(-0.5)) {
|
|
// We limit to a max of 7 multiplications, thus the maximum exponent is 32.
|
|
// If the exponent is an integer+0.5 we generate a call to sqrt and an
|
|
// additional fmul.
|
|
// TODO: This whole transformation should be backend specific (e.g. some
|
|
// backends might prefer libcalls or the limit for the exponent might
|
|
// be different) and it should also consider optimizing for size.
|
|
APFloat LimF(ExpoF->getSemantics(), 33),
|
|
ExpoA(abs(*ExpoF));
|
|
if (ExpoA < LimF) {
|
|
// This transformation applies to integer or integer+0.5 exponents only.
|
|
// For integer+0.5, we create a sqrt(Base) call.
|
|
Value *Sqrt = nullptr;
|
|
if (!ExpoA.isInteger()) {
|
|
APFloat Expo2 = ExpoA;
|
|
// To check if ExpoA is an integer + 0.5, we add it to itself. If there
|
|
// is no floating point exception and the result is an integer, then
|
|
// ExpoA == integer + 0.5
|
|
if (Expo2.add(ExpoA, APFloat::rmNearestTiesToEven) != APFloat::opOK)
|
|
return nullptr;
|
|
|
|
if (!Expo2.isInteger())
|
|
return nullptr;
|
|
|
|
Sqrt = getSqrtCall(Base, Pow->getCalledFunction()->getAttributes(),
|
|
Pow->doesNotAccessMemory(), M, B, TLI);
|
|
if (!Sqrt)
|
|
return nullptr;
|
|
}
|
|
|
|
// We will memoize intermediate products of the Addition Chain.
|
|
Value *InnerChain[33] = {nullptr};
|
|
InnerChain[1] = Base;
|
|
InnerChain[2] = B.CreateFMul(Base, Base, "square");
|
|
|
|
// We cannot readily convert a non-double type (like float) to a double.
|
|
// So we first convert it to something which could be converted to double.
|
|
ExpoA.convert(APFloat::IEEEdouble(), APFloat::rmTowardZero, &Ignored);
|
|
Value *FMul = getPow(InnerChain, ExpoA.convertToDouble(), B);
|
|
|
|
// Expand pow(x, y+0.5) to pow(x, y) * sqrt(x).
|
|
if (Sqrt)
|
|
FMul = B.CreateFMul(FMul, Sqrt);
|
|
|
|
// If the exponent is negative, then get the reciprocal.
|
|
if (ExpoF->isNegative())
|
|
FMul = B.CreateFDiv(ConstantFP::get(Ty, 1.0), FMul, "reciprocal");
|
|
|
|
return FMul;
|
|
}
|
|
|
|
APSInt IntExpo(32, /*isUnsigned=*/false);
|
|
// powf(x, n) -> powi(x, n) if n is a constant signed integer value
|
|
if (ExpoF->isInteger() &&
|
|
ExpoF->convertToInteger(IntExpo, APFloat::rmTowardZero, &Ignored) ==
|
|
APFloat::opOK) {
|
|
return createPowWithIntegerExponent(
|
|
Base, ConstantInt::get(B.getInt32Ty(), IntExpo), M, B);
|
|
}
|
|
}
|
|
|
|
// powf(x, itofp(y)) -> powi(x, y)
|
|
if (AllowApprox && (isa<SIToFPInst>(Expo) || isa<UIToFPInst>(Expo))) {
|
|
if (Value *ExpoI = getIntToFPVal(Expo, B))
|
|
return createPowWithIntegerExponent(Base, ExpoI, M, B);
|
|
}
|
|
|
|
return Shrunk;
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeExp2(CallInst *CI, IRBuilderBase &B) {
|
|
Function *Callee = CI->getCalledFunction();
|
|
AttributeList Attrs; // Attributes are only meaningful on the original call
|
|
StringRef Name = Callee->getName();
|
|
Value *Ret = nullptr;
|
|
if (UnsafeFPShrink && Name == TLI->getName(LibFunc_exp2) &&
|
|
hasFloatVersion(Name))
|
|
Ret = optimizeUnaryDoubleFP(CI, B, true);
|
|
|
|
Type *Ty = CI->getType();
|
|
Value *Op = CI->getArgOperand(0);
|
|
|
|
// Turn exp2(sitofp(x)) -> ldexp(1.0, sext(x)) if sizeof(x) <= 32
|
|
// Turn exp2(uitofp(x)) -> ldexp(1.0, zext(x)) if sizeof(x) < 32
|
|
if ((isa<SIToFPInst>(Op) || isa<UIToFPInst>(Op)) &&
|
|
hasFloatFn(TLI, Ty, LibFunc_ldexp, LibFunc_ldexpf, LibFunc_ldexpl)) {
|
|
if (Value *Exp = getIntToFPVal(Op, B))
|
|
return emitBinaryFloatFnCall(ConstantFP::get(Ty, 1.0), Exp, TLI,
|
|
LibFunc_ldexp, LibFunc_ldexpf, LibFunc_ldexpl,
|
|
B, Attrs);
|
|
}
|
|
|
|
return Ret;
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeFMinFMax(CallInst *CI, IRBuilderBase &B) {
|
|
// If we can shrink the call to a float function rather than a double
|
|
// function, do that first.
|
|
Function *Callee = CI->getCalledFunction();
|
|
StringRef Name = Callee->getName();
|
|
if ((Name == "fmin" || Name == "fmax") && hasFloatVersion(Name))
|
|
if (Value *Ret = optimizeBinaryDoubleFP(CI, B))
|
|
return Ret;
|
|
|
|
// The LLVM intrinsics minnum/maxnum correspond to fmin/fmax. Canonicalize to
|
|
// the intrinsics for improved optimization (for example, vectorization).
|
|
// No-signed-zeros is implied by the definitions of fmax/fmin themselves.
|
|
// From the C standard draft WG14/N1256:
|
|
// "Ideally, fmax would be sensitive to the sign of zero, for example
|
|
// fmax(-0.0, +0.0) would return +0; however, implementation in software
|
|
// might be impractical."
|
|
IRBuilderBase::FastMathFlagGuard Guard(B);
|
|
FastMathFlags FMF = CI->getFastMathFlags();
|
|
FMF.setNoSignedZeros();
|
|
B.setFastMathFlags(FMF);
|
|
|
|
Intrinsic::ID IID = Callee->getName().startswith("fmin") ? Intrinsic::minnum
|
|
: Intrinsic::maxnum;
|
|
Function *F = Intrinsic::getDeclaration(CI->getModule(), IID, CI->getType());
|
|
return B.CreateCall(F, { CI->getArgOperand(0), CI->getArgOperand(1) });
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeLog(CallInst *Log, IRBuilderBase &B) {
|
|
Function *LogFn = Log->getCalledFunction();
|
|
AttributeList Attrs; // Attributes are only meaningful on the original call
|
|
StringRef LogNm = LogFn->getName();
|
|
Intrinsic::ID LogID = LogFn->getIntrinsicID();
|
|
Module *Mod = Log->getModule();
|
|
Type *Ty = Log->getType();
|
|
Value *Ret = nullptr;
|
|
|
|
if (UnsafeFPShrink && hasFloatVersion(LogNm))
|
|
Ret = optimizeUnaryDoubleFP(Log, B, true);
|
|
|
|
// The earlier call must also be 'fast' in order to do these transforms.
|
|
CallInst *Arg = dyn_cast<CallInst>(Log->getArgOperand(0));
|
|
if (!Log->isFast() || !Arg || !Arg->isFast() || !Arg->hasOneUse())
|
|
return Ret;
|
|
|
|
LibFunc LogLb, ExpLb, Exp2Lb, Exp10Lb, PowLb;
|
|
|
|
// This is only applicable to log(), log2(), log10().
|
|
if (TLI->getLibFunc(LogNm, LogLb))
|
|
switch (LogLb) {
|
|
case LibFunc_logf:
|
|
LogID = Intrinsic::log;
|
|
ExpLb = LibFunc_expf;
|
|
Exp2Lb = LibFunc_exp2f;
|
|
Exp10Lb = LibFunc_exp10f;
|
|
PowLb = LibFunc_powf;
|
|
break;
|
|
case LibFunc_log:
|
|
LogID = Intrinsic::log;
|
|
ExpLb = LibFunc_exp;
|
|
Exp2Lb = LibFunc_exp2;
|
|
Exp10Lb = LibFunc_exp10;
|
|
PowLb = LibFunc_pow;
|
|
break;
|
|
case LibFunc_logl:
|
|
LogID = Intrinsic::log;
|
|
ExpLb = LibFunc_expl;
|
|
Exp2Lb = LibFunc_exp2l;
|
|
Exp10Lb = LibFunc_exp10l;
|
|
PowLb = LibFunc_powl;
|
|
break;
|
|
case LibFunc_log2f:
|
|
LogID = Intrinsic::log2;
|
|
ExpLb = LibFunc_expf;
|
|
Exp2Lb = LibFunc_exp2f;
|
|
Exp10Lb = LibFunc_exp10f;
|
|
PowLb = LibFunc_powf;
|
|
break;
|
|
case LibFunc_log2:
|
|
LogID = Intrinsic::log2;
|
|
ExpLb = LibFunc_exp;
|
|
Exp2Lb = LibFunc_exp2;
|
|
Exp10Lb = LibFunc_exp10;
|
|
PowLb = LibFunc_pow;
|
|
break;
|
|
case LibFunc_log2l:
|
|
LogID = Intrinsic::log2;
|
|
ExpLb = LibFunc_expl;
|
|
Exp2Lb = LibFunc_exp2l;
|
|
Exp10Lb = LibFunc_exp10l;
|
|
PowLb = LibFunc_powl;
|
|
break;
|
|
case LibFunc_log10f:
|
|
LogID = Intrinsic::log10;
|
|
ExpLb = LibFunc_expf;
|
|
Exp2Lb = LibFunc_exp2f;
|
|
Exp10Lb = LibFunc_exp10f;
|
|
PowLb = LibFunc_powf;
|
|
break;
|
|
case LibFunc_log10:
|
|
LogID = Intrinsic::log10;
|
|
ExpLb = LibFunc_exp;
|
|
Exp2Lb = LibFunc_exp2;
|
|
Exp10Lb = LibFunc_exp10;
|
|
PowLb = LibFunc_pow;
|
|
break;
|
|
case LibFunc_log10l:
|
|
LogID = Intrinsic::log10;
|
|
ExpLb = LibFunc_expl;
|
|
Exp2Lb = LibFunc_exp2l;
|
|
Exp10Lb = LibFunc_exp10l;
|
|
PowLb = LibFunc_powl;
|
|
break;
|
|
default:
|
|
return Ret;
|
|
}
|
|
else if (LogID == Intrinsic::log || LogID == Intrinsic::log2 ||
|
|
LogID == Intrinsic::log10) {
|
|
if (Ty->getScalarType()->isFloatTy()) {
|
|
ExpLb = LibFunc_expf;
|
|
Exp2Lb = LibFunc_exp2f;
|
|
Exp10Lb = LibFunc_exp10f;
|
|
PowLb = LibFunc_powf;
|
|
} else if (Ty->getScalarType()->isDoubleTy()) {
|
|
ExpLb = LibFunc_exp;
|
|
Exp2Lb = LibFunc_exp2;
|
|
Exp10Lb = LibFunc_exp10;
|
|
PowLb = LibFunc_pow;
|
|
} else
|
|
return Ret;
|
|
} else
|
|
return Ret;
|
|
|
|
IRBuilderBase::FastMathFlagGuard Guard(B);
|
|
B.setFastMathFlags(FastMathFlags::getFast());
|
|
|
|
Intrinsic::ID ArgID = Arg->getIntrinsicID();
|
|
LibFunc ArgLb = NotLibFunc;
|
|
TLI->getLibFunc(*Arg, ArgLb);
|
|
|
|
// log(pow(x,y)) -> y*log(x)
|
|
if (ArgLb == PowLb || ArgID == Intrinsic::pow) {
|
|
Value *LogX =
|
|
Log->doesNotAccessMemory()
|
|
? B.CreateCall(Intrinsic::getDeclaration(Mod, LogID, Ty),
|
|
Arg->getOperand(0), "log")
|
|
: emitUnaryFloatFnCall(Arg->getOperand(0), LogNm, B, Attrs);
|
|
Value *MulY = B.CreateFMul(Arg->getArgOperand(1), LogX, "mul");
|
|
// Since pow() may have side effects, e.g. errno,
|
|
// dead code elimination may not be trusted to remove it.
|
|
substituteInParent(Arg, MulY);
|
|
return MulY;
|
|
}
|
|
|
|
// log(exp{,2,10}(y)) -> y*log({e,2,10})
|
|
// TODO: There is no exp10() intrinsic yet.
|
|
if (ArgLb == ExpLb || ArgLb == Exp2Lb || ArgLb == Exp10Lb ||
|
|
ArgID == Intrinsic::exp || ArgID == Intrinsic::exp2) {
|
|
Constant *Eul;
|
|
if (ArgLb == ExpLb || ArgID == Intrinsic::exp)
|
|
// FIXME: Add more precise value of e for long double.
|
|
Eul = ConstantFP::get(Log->getType(), numbers::e);
|
|
else if (ArgLb == Exp2Lb || ArgID == Intrinsic::exp2)
|
|
Eul = ConstantFP::get(Log->getType(), 2.0);
|
|
else
|
|
Eul = ConstantFP::get(Log->getType(), 10.0);
|
|
Value *LogE = Log->doesNotAccessMemory()
|
|
? B.CreateCall(Intrinsic::getDeclaration(Mod, LogID, Ty),
|
|
Eul, "log")
|
|
: emitUnaryFloatFnCall(Eul, LogNm, B, Attrs);
|
|
Value *MulY = B.CreateFMul(Arg->getArgOperand(0), LogE, "mul");
|
|
// Since exp() may have side effects, e.g. errno,
|
|
// dead code elimination may not be trusted to remove it.
|
|
substituteInParent(Arg, MulY);
|
|
return MulY;
|
|
}
|
|
|
|
return Ret;
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeSqrt(CallInst *CI, IRBuilderBase &B) {
|
|
Function *Callee = CI->getCalledFunction();
|
|
Value *Ret = nullptr;
|
|
// TODO: Once we have a way (other than checking for the existince of the
|
|
// libcall) to tell whether our target can lower @llvm.sqrt, relax the
|
|
// condition below.
|
|
if (TLI->has(LibFunc_sqrtf) && (Callee->getName() == "sqrt" ||
|
|
Callee->getIntrinsicID() == Intrinsic::sqrt))
|
|
Ret = optimizeUnaryDoubleFP(CI, B, true);
|
|
|
|
if (!CI->isFast())
|
|
return Ret;
|
|
|
|
Instruction *I = dyn_cast<Instruction>(CI->getArgOperand(0));
|
|
if (!I || I->getOpcode() != Instruction::FMul || !I->isFast())
|
|
return Ret;
|
|
|
|
// We're looking for a repeated factor in a multiplication tree,
|
|
// so we can do this fold: sqrt(x * x) -> fabs(x);
|
|
// or this fold: sqrt((x * x) * y) -> fabs(x) * sqrt(y).
|
|
Value *Op0 = I->getOperand(0);
|
|
Value *Op1 = I->getOperand(1);
|
|
Value *RepeatOp = nullptr;
|
|
Value *OtherOp = nullptr;
|
|
if (Op0 == Op1) {
|
|
// Simple match: the operands of the multiply are identical.
|
|
RepeatOp = Op0;
|
|
} else {
|
|
// Look for a more complicated pattern: one of the operands is itself
|
|
// a multiply, so search for a common factor in that multiply.
|
|
// Note: We don't bother looking any deeper than this first level or for
|
|
// variations of this pattern because instcombine's visitFMUL and/or the
|
|
// reassociation pass should give us this form.
|
|
Value *OtherMul0, *OtherMul1;
|
|
if (match(Op0, m_FMul(m_Value(OtherMul0), m_Value(OtherMul1)))) {
|
|
// Pattern: sqrt((x * y) * z)
|
|
if (OtherMul0 == OtherMul1 && cast<Instruction>(Op0)->isFast()) {
|
|
// Matched: sqrt((x * x) * z)
|
|
RepeatOp = OtherMul0;
|
|
OtherOp = Op1;
|
|
}
|
|
}
|
|
}
|
|
if (!RepeatOp)
|
|
return Ret;
|
|
|
|
// Fast math flags for any created instructions should match the sqrt
|
|
// and multiply.
|
|
IRBuilderBase::FastMathFlagGuard Guard(B);
|
|
B.setFastMathFlags(I->getFastMathFlags());
|
|
|
|
// If we found a repeated factor, hoist it out of the square root and
|
|
// replace it with the fabs of that factor.
|
|
Module *M = Callee->getParent();
|
|
Type *ArgType = I->getType();
|
|
Function *Fabs = Intrinsic::getDeclaration(M, Intrinsic::fabs, ArgType);
|
|
Value *FabsCall = B.CreateCall(Fabs, RepeatOp, "fabs");
|
|
if (OtherOp) {
|
|
// If we found a non-repeated factor, we still need to get its square
|
|
// root. We then multiply that by the value that was simplified out
|
|
// of the square root calculation.
|
|
Function *Sqrt = Intrinsic::getDeclaration(M, Intrinsic::sqrt, ArgType);
|
|
Value *SqrtCall = B.CreateCall(Sqrt, OtherOp, "sqrt");
|
|
return B.CreateFMul(FabsCall, SqrtCall);
|
|
}
|
|
return FabsCall;
|
|
}
|
|
|
|
// TODO: Generalize to handle any trig function and its inverse.
|
|
Value *LibCallSimplifier::optimizeTan(CallInst *CI, IRBuilderBase &B) {
|
|
Function *Callee = CI->getCalledFunction();
|
|
Value *Ret = nullptr;
|
|
StringRef Name = Callee->getName();
|
|
if (UnsafeFPShrink && Name == "tan" && hasFloatVersion(Name))
|
|
Ret = optimizeUnaryDoubleFP(CI, B, true);
|
|
|
|
Value *Op1 = CI->getArgOperand(0);
|
|
auto *OpC = dyn_cast<CallInst>(Op1);
|
|
if (!OpC)
|
|
return Ret;
|
|
|
|
// Both calls must be 'fast' in order to remove them.
|
|
if (!CI->isFast() || !OpC->isFast())
|
|
return Ret;
|
|
|
|
// tan(atan(x)) -> x
|
|
// tanf(atanf(x)) -> x
|
|
// tanl(atanl(x)) -> x
|
|
LibFunc Func;
|
|
Function *F = OpC->getCalledFunction();
|
|
if (F && TLI->getLibFunc(F->getName(), Func) && TLI->has(Func) &&
|
|
((Func == LibFunc_atan && Callee->getName() == "tan") ||
|
|
(Func == LibFunc_atanf && Callee->getName() == "tanf") ||
|
|
(Func == LibFunc_atanl && Callee->getName() == "tanl")))
|
|
Ret = OpC->getArgOperand(0);
|
|
return Ret;
|
|
}
|
|
|
|
static bool isTrigLibCall(CallInst *CI) {
|
|
// We can only hope to do anything useful if we can ignore things like errno
|
|
// and floating-point exceptions.
|
|
// We already checked the prototype.
|
|
return CI->hasFnAttr(Attribute::NoUnwind) &&
|
|
CI->hasFnAttr(Attribute::ReadNone);
|
|
}
|
|
|
|
static void insertSinCosCall(IRBuilderBase &B, Function *OrigCallee, Value *Arg,
|
|
bool UseFloat, Value *&Sin, Value *&Cos,
|
|
Value *&SinCos) {
|
|
Type *ArgTy = Arg->getType();
|
|
Type *ResTy;
|
|
StringRef Name;
|
|
|
|
Triple T(OrigCallee->getParent()->getTargetTriple());
|
|
if (UseFloat) {
|
|
Name = "__sincospif_stret";
|
|
|
|
assert(T.getArch() != Triple::x86 && "x86 messy and unsupported for now");
|
|
// x86_64 can't use {float, float} since that would be returned in both
|
|
// xmm0 and xmm1, which isn't what a real struct would do.
|
|
ResTy = T.getArch() == Triple::x86_64
|
|
? static_cast<Type *>(FixedVectorType::get(ArgTy, 2))
|
|
: static_cast<Type *>(StructType::get(ArgTy, ArgTy));
|
|
} else {
|
|
Name = "__sincospi_stret";
|
|
ResTy = StructType::get(ArgTy, ArgTy);
|
|
}
|
|
|
|
Module *M = OrigCallee->getParent();
|
|
FunctionCallee Callee =
|
|
M->getOrInsertFunction(Name, OrigCallee->getAttributes(), ResTy, ArgTy);
|
|
|
|
if (Instruction *ArgInst = dyn_cast<Instruction>(Arg)) {
|
|
// If the argument is an instruction, it must dominate all uses so put our
|
|
// sincos call there.
|
|
B.SetInsertPoint(ArgInst->getParent(), ++ArgInst->getIterator());
|
|
} else {
|
|
// Otherwise (e.g. for a constant) the beginning of the function is as
|
|
// good a place as any.
|
|
BasicBlock &EntryBB = B.GetInsertBlock()->getParent()->getEntryBlock();
|
|
B.SetInsertPoint(&EntryBB, EntryBB.begin());
|
|
}
|
|
|
|
SinCos = B.CreateCall(Callee, Arg, "sincospi");
|
|
|
|
if (SinCos->getType()->isStructTy()) {
|
|
Sin = B.CreateExtractValue(SinCos, 0, "sinpi");
|
|
Cos = B.CreateExtractValue(SinCos, 1, "cospi");
|
|
} else {
|
|
Sin = B.CreateExtractElement(SinCos, ConstantInt::get(B.getInt32Ty(), 0),
|
|
"sinpi");
|
|
Cos = B.CreateExtractElement(SinCos, ConstantInt::get(B.getInt32Ty(), 1),
|
|
"cospi");
|
|
}
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeSinCosPi(CallInst *CI, IRBuilderBase &B) {
|
|
// Make sure the prototype is as expected, otherwise the rest of the
|
|
// function is probably invalid and likely to abort.
|
|
if (!isTrigLibCall(CI))
|
|
return nullptr;
|
|
|
|
Value *Arg = CI->getArgOperand(0);
|
|
SmallVector<CallInst *, 1> SinCalls;
|
|
SmallVector<CallInst *, 1> CosCalls;
|
|
SmallVector<CallInst *, 1> SinCosCalls;
|
|
|
|
bool IsFloat = Arg->getType()->isFloatTy();
|
|
|
|
// Look for all compatible sinpi, cospi and sincospi calls with the same
|
|
// argument. If there are enough (in some sense) we can make the
|
|
// substitution.
|
|
Function *F = CI->getFunction();
|
|
for (User *U : Arg->users())
|
|
classifyArgUse(U, F, IsFloat, SinCalls, CosCalls, SinCosCalls);
|
|
|
|
// It's only worthwhile if both sinpi and cospi are actually used.
|
|
if (SinCalls.empty() || CosCalls.empty())
|
|
return nullptr;
|
|
|
|
Value *Sin, *Cos, *SinCos;
|
|
insertSinCosCall(B, CI->getCalledFunction(), Arg, IsFloat, Sin, Cos, SinCos);
|
|
|
|
auto replaceTrigInsts = [this](SmallVectorImpl<CallInst *> &Calls,
|
|
Value *Res) {
|
|
for (CallInst *C : Calls)
|
|
replaceAllUsesWith(C, Res);
|
|
};
|
|
|
|
replaceTrigInsts(SinCalls, Sin);
|
|
replaceTrigInsts(CosCalls, Cos);
|
|
replaceTrigInsts(SinCosCalls, SinCos);
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
void LibCallSimplifier::classifyArgUse(
|
|
Value *Val, Function *F, bool IsFloat,
|
|
SmallVectorImpl<CallInst *> &SinCalls,
|
|
SmallVectorImpl<CallInst *> &CosCalls,
|
|
SmallVectorImpl<CallInst *> &SinCosCalls) {
|
|
CallInst *CI = dyn_cast<CallInst>(Val);
|
|
|
|
if (!CI || CI->use_empty())
|
|
return;
|
|
|
|
// Don't consider calls in other functions.
|
|
if (CI->getFunction() != F)
|
|
return;
|
|
|
|
Function *Callee = CI->getCalledFunction();
|
|
LibFunc Func;
|
|
if (!Callee || !TLI->getLibFunc(*Callee, Func) || !TLI->has(Func) ||
|
|
!isTrigLibCall(CI))
|
|
return;
|
|
|
|
if (IsFloat) {
|
|
if (Func == LibFunc_sinpif)
|
|
SinCalls.push_back(CI);
|
|
else if (Func == LibFunc_cospif)
|
|
CosCalls.push_back(CI);
|
|
else if (Func == LibFunc_sincospif_stret)
|
|
SinCosCalls.push_back(CI);
|
|
} else {
|
|
if (Func == LibFunc_sinpi)
|
|
SinCalls.push_back(CI);
|
|
else if (Func == LibFunc_cospi)
|
|
CosCalls.push_back(CI);
|
|
else if (Func == LibFunc_sincospi_stret)
|
|
SinCosCalls.push_back(CI);
|
|
}
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Integer Library Call Optimizations
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
Value *LibCallSimplifier::optimizeFFS(CallInst *CI, IRBuilderBase &B) {
|
|
// ffs(x) -> x != 0 ? (i32)llvm.cttz(x)+1 : 0
|
|
Value *Op = CI->getArgOperand(0);
|
|
Type *ArgType = Op->getType();
|
|
Function *F = Intrinsic::getDeclaration(CI->getCalledFunction()->getParent(),
|
|
Intrinsic::cttz, ArgType);
|
|
Value *V = B.CreateCall(F, {Op, B.getTrue()}, "cttz");
|
|
V = B.CreateAdd(V, ConstantInt::get(V->getType(), 1));
|
|
V = B.CreateIntCast(V, B.getInt32Ty(), false);
|
|
|
|
Value *Cond = B.CreateICmpNE(Op, Constant::getNullValue(ArgType));
|
|
return B.CreateSelect(Cond, V, B.getInt32(0));
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeFls(CallInst *CI, IRBuilderBase &B) {
|
|
// fls(x) -> (i32)(sizeInBits(x) - llvm.ctlz(x, false))
|
|
Value *Op = CI->getArgOperand(0);
|
|
Type *ArgType = Op->getType();
|
|
Function *F = Intrinsic::getDeclaration(CI->getCalledFunction()->getParent(),
|
|
Intrinsic::ctlz, ArgType);
|
|
Value *V = B.CreateCall(F, {Op, B.getFalse()}, "ctlz");
|
|
V = B.CreateSub(ConstantInt::get(V->getType(), ArgType->getIntegerBitWidth()),
|
|
V);
|
|
return B.CreateIntCast(V, CI->getType(), false);
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeAbs(CallInst *CI, IRBuilderBase &B) {
|
|
// abs(x) -> x <s 0 ? -x : x
|
|
// The negation has 'nsw' because abs of INT_MIN is undefined.
|
|
Value *X = CI->getArgOperand(0);
|
|
Value *IsNeg = B.CreateICmpSLT(X, Constant::getNullValue(X->getType()));
|
|
Value *NegX = B.CreateNSWNeg(X, "neg");
|
|
return B.CreateSelect(IsNeg, NegX, X);
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeIsDigit(CallInst *CI, IRBuilderBase &B) {
|
|
// isdigit(c) -> (c-'0') <u 10
|
|
Value *Op = CI->getArgOperand(0);
|
|
Op = B.CreateSub(Op, B.getInt32('0'), "isdigittmp");
|
|
Op = B.CreateICmpULT(Op, B.getInt32(10), "isdigit");
|
|
return B.CreateZExt(Op, CI->getType());
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeIsAscii(CallInst *CI, IRBuilderBase &B) {
|
|
// isascii(c) -> c <u 128
|
|
Value *Op = CI->getArgOperand(0);
|
|
Op = B.CreateICmpULT(Op, B.getInt32(128), "isascii");
|
|
return B.CreateZExt(Op, CI->getType());
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeToAscii(CallInst *CI, IRBuilderBase &B) {
|
|
// toascii(c) -> c & 0x7f
|
|
return B.CreateAnd(CI->getArgOperand(0),
|
|
ConstantInt::get(CI->getType(), 0x7F));
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeAtoi(CallInst *CI, IRBuilderBase &B) {
|
|
StringRef Str;
|
|
if (!getConstantStringInfo(CI->getArgOperand(0), Str))
|
|
return nullptr;
|
|
|
|
return convertStrToNumber(CI, Str, 10);
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeStrtol(CallInst *CI, IRBuilderBase &B) {
|
|
StringRef Str;
|
|
if (!getConstantStringInfo(CI->getArgOperand(0), Str))
|
|
return nullptr;
|
|
|
|
if (!isa<ConstantPointerNull>(CI->getArgOperand(1)))
|
|
return nullptr;
|
|
|
|
if (ConstantInt *CInt = dyn_cast<ConstantInt>(CI->getArgOperand(2))) {
|
|
return convertStrToNumber(CI, Str, CInt->getSExtValue());
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Formatting and IO Library Call Optimizations
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
static bool isReportingError(Function *Callee, CallInst *CI, int StreamArg);
|
|
|
|
Value *LibCallSimplifier::optimizeErrorReporting(CallInst *CI, IRBuilderBase &B,
|
|
int StreamArg) {
|
|
Function *Callee = CI->getCalledFunction();
|
|
// Error reporting calls should be cold, mark them as such.
|
|
// This applies even to non-builtin calls: it is only a hint and applies to
|
|
// functions that the frontend might not understand as builtins.
|
|
|
|
// This heuristic was suggested in:
|
|
// Improving Static Branch Prediction in a Compiler
|
|
// Brian L. Deitrich, Ben-Chung Cheng, Wen-mei W. Hwu
|
|
// Proceedings of PACT'98, Oct. 1998, IEEE
|
|
if (!CI->hasFnAttr(Attribute::Cold) &&
|
|
isReportingError(Callee, CI, StreamArg)) {
|
|
CI->addAttribute(AttributeList::FunctionIndex, Attribute::Cold);
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
static bool isReportingError(Function *Callee, CallInst *CI, int StreamArg) {
|
|
if (!Callee || !Callee->isDeclaration())
|
|
return false;
|
|
|
|
if (StreamArg < 0)
|
|
return true;
|
|
|
|
// These functions might be considered cold, but only if their stream
|
|
// argument is stderr.
|
|
|
|
if (StreamArg >= (int)CI->getNumArgOperands())
|
|
return false;
|
|
LoadInst *LI = dyn_cast<LoadInst>(CI->getArgOperand(StreamArg));
|
|
if (!LI)
|
|
return false;
|
|
GlobalVariable *GV = dyn_cast<GlobalVariable>(LI->getPointerOperand());
|
|
if (!GV || !GV->isDeclaration())
|
|
return false;
|
|
return GV->getName() == "stderr";
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizePrintFString(CallInst *CI, IRBuilderBase &B) {
|
|
// Check for a fixed format string.
|
|
StringRef FormatStr;
|
|
if (!getConstantStringInfo(CI->getArgOperand(0), FormatStr))
|
|
return nullptr;
|
|
|
|
// Empty format string -> noop.
|
|
if (FormatStr.empty()) // Tolerate printf's declared void.
|
|
return CI->use_empty() ? (Value *)CI : ConstantInt::get(CI->getType(), 0);
|
|
|
|
// Do not do any of the following transformations if the printf return value
|
|
// is used, in general the printf return value is not compatible with either
|
|
// putchar() or puts().
|
|
if (!CI->use_empty())
|
|
return nullptr;
|
|
|
|
// printf("x") -> putchar('x'), even for "%" and "%%".
|
|
if (FormatStr.size() == 1 || FormatStr == "%%")
|
|
return emitPutChar(B.getInt32(FormatStr[0]), B, TLI);
|
|
|
|
// printf("%s", "a") --> putchar('a')
|
|
if (FormatStr == "%s" && CI->getNumArgOperands() > 1) {
|
|
StringRef ChrStr;
|
|
if (!getConstantStringInfo(CI->getOperand(1), ChrStr))
|
|
return nullptr;
|
|
if (ChrStr.size() != 1)
|
|
return nullptr;
|
|
return emitPutChar(B.getInt32(ChrStr[0]), B, TLI);
|
|
}
|
|
|
|
// printf("foo\n") --> puts("foo")
|
|
if (FormatStr[FormatStr.size() - 1] == '\n' &&
|
|
FormatStr.find('%') == StringRef::npos) { // No format characters.
|
|
// Create a string literal with no \n on it. We expect the constant merge
|
|
// pass to be run after this pass, to merge duplicate strings.
|
|
FormatStr = FormatStr.drop_back();
|
|
Value *GV = B.CreateGlobalString(FormatStr, "str");
|
|
return emitPutS(GV, B, TLI);
|
|
}
|
|
|
|
// Optimize specific format strings.
|
|
// printf("%c", chr) --> putchar(chr)
|
|
if (FormatStr == "%c" && CI->getNumArgOperands() > 1 &&
|
|
CI->getArgOperand(1)->getType()->isIntegerTy())
|
|
return emitPutChar(CI->getArgOperand(1), B, TLI);
|
|
|
|
// printf("%s\n", str) --> puts(str)
|
|
if (FormatStr == "%s\n" && CI->getNumArgOperands() > 1 &&
|
|
CI->getArgOperand(1)->getType()->isPointerTy())
|
|
return emitPutS(CI->getArgOperand(1), B, TLI);
|
|
return nullptr;
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizePrintF(CallInst *CI, IRBuilderBase &B) {
|
|
|
|
Function *Callee = CI->getCalledFunction();
|
|
FunctionType *FT = Callee->getFunctionType();
|
|
if (Value *V = optimizePrintFString(CI, B)) {
|
|
return V;
|
|
}
|
|
|
|
// printf(format, ...) -> iprintf(format, ...) if no floating point
|
|
// arguments.
|
|
if (TLI->has(LibFunc_iprintf) && !callHasFloatingPointArgument(CI)) {
|
|
Module *M = B.GetInsertBlock()->getParent()->getParent();
|
|
FunctionCallee IPrintFFn =
|
|
M->getOrInsertFunction("iprintf", FT, Callee->getAttributes());
|
|
CallInst *New = cast<CallInst>(CI->clone());
|
|
New->setCalledFunction(IPrintFFn);
|
|
B.Insert(New);
|
|
return New;
|
|
}
|
|
|
|
// printf(format, ...) -> __small_printf(format, ...) if no 128-bit floating point
|
|
// arguments.
|
|
if (TLI->has(LibFunc_small_printf) && !callHasFP128Argument(CI)) {
|
|
Module *M = B.GetInsertBlock()->getParent()->getParent();
|
|
auto SmallPrintFFn =
|
|
M->getOrInsertFunction(TLI->getName(LibFunc_small_printf),
|
|
FT, Callee->getAttributes());
|
|
CallInst *New = cast<CallInst>(CI->clone());
|
|
New->setCalledFunction(SmallPrintFFn);
|
|
B.Insert(New);
|
|
return New;
|
|
}
|
|
|
|
annotateNonNullBasedOnAccess(CI, 0);
|
|
return nullptr;
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeSPrintFString(CallInst *CI,
|
|
IRBuilderBase &B) {
|
|
// Check for a fixed format string.
|
|
StringRef FormatStr;
|
|
if (!getConstantStringInfo(CI->getArgOperand(1), FormatStr))
|
|
return nullptr;
|
|
|
|
// If we just have a format string (nothing else crazy) transform it.
|
|
if (CI->getNumArgOperands() == 2) {
|
|
// Make sure there's no % in the constant array. We could try to handle
|
|
// %% -> % in the future if we cared.
|
|
if (FormatStr.find('%') != StringRef::npos)
|
|
return nullptr; // we found a format specifier, bail out.
|
|
|
|
// sprintf(str, fmt) -> llvm.memcpy(align 1 str, align 1 fmt, strlen(fmt)+1)
|
|
B.CreateMemCpy(
|
|
CI->getArgOperand(0), Align(1), CI->getArgOperand(1), Align(1),
|
|
ConstantInt::get(DL.getIntPtrType(CI->getContext()),
|
|
FormatStr.size() + 1)); // Copy the null byte.
|
|
return ConstantInt::get(CI->getType(), FormatStr.size());
|
|
}
|
|
|
|
// The remaining optimizations require the format string to be "%s" or "%c"
|
|
// and have an extra operand.
|
|
if (FormatStr.size() != 2 || FormatStr[0] != '%' ||
|
|
CI->getNumArgOperands() < 3)
|
|
return nullptr;
|
|
|
|
// Decode the second character of the format string.
|
|
if (FormatStr[1] == 'c') {
|
|
// sprintf(dst, "%c", chr) --> *(i8*)dst = chr; *((i8*)dst+1) = 0
|
|
if (!CI->getArgOperand(2)->getType()->isIntegerTy())
|
|
return nullptr;
|
|
Value *V = B.CreateTrunc(CI->getArgOperand(2), B.getInt8Ty(), "char");
|
|
Value *Ptr = castToCStr(CI->getArgOperand(0), B);
|
|
B.CreateStore(V, Ptr);
|
|
Ptr = B.CreateGEP(B.getInt8Ty(), Ptr, B.getInt32(1), "nul");
|
|
B.CreateStore(B.getInt8(0), Ptr);
|
|
|
|
return ConstantInt::get(CI->getType(), 1);
|
|
}
|
|
|
|
if (FormatStr[1] == 's') {
|
|
// sprintf(dest, "%s", str) -> llvm.memcpy(align 1 dest, align 1 str,
|
|
// strlen(str)+1)
|
|
if (!CI->getArgOperand(2)->getType()->isPointerTy())
|
|
return nullptr;
|
|
|
|
if (CI->use_empty())
|
|
// sprintf(dest, "%s", str) -> strcpy(dest, str)
|
|
return emitStrCpy(CI->getArgOperand(0), CI->getArgOperand(2), B, TLI);
|
|
|
|
uint64_t SrcLen = GetStringLength(CI->getArgOperand(2));
|
|
if (SrcLen) {
|
|
B.CreateMemCpy(
|
|
CI->getArgOperand(0), Align(1), CI->getArgOperand(2), Align(1),
|
|
ConstantInt::get(DL.getIntPtrType(CI->getContext()), SrcLen));
|
|
// Returns total number of characters written without null-character.
|
|
return ConstantInt::get(CI->getType(), SrcLen - 1);
|
|
} else if (Value *V = emitStpCpy(CI->getArgOperand(0), CI->getArgOperand(2),
|
|
B, TLI)) {
|
|
// sprintf(dest, "%s", str) -> stpcpy(dest, str) - dest
|
|
Value *PtrDiff = B.CreatePtrDiff(V, CI->getArgOperand(0));
|
|
return B.CreateIntCast(PtrDiff, CI->getType(), false);
|
|
}
|
|
|
|
bool OptForSize = CI->getFunction()->hasOptSize() ||
|
|
llvm::shouldOptimizeForSize(CI->getParent(), PSI, BFI,
|
|
PGSOQueryType::IRPass);
|
|
if (OptForSize)
|
|
return nullptr;
|
|
|
|
Value *Len = emitStrLen(CI->getArgOperand(2), B, DL, TLI);
|
|
if (!Len)
|
|
return nullptr;
|
|
Value *IncLen =
|
|
B.CreateAdd(Len, ConstantInt::get(Len->getType(), 1), "leninc");
|
|
B.CreateMemCpy(CI->getArgOperand(0), Align(1), CI->getArgOperand(2),
|
|
Align(1), IncLen);
|
|
|
|
// The sprintf result is the unincremented number of bytes in the string.
|
|
return B.CreateIntCast(Len, CI->getType(), false);
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeSPrintF(CallInst *CI, IRBuilderBase &B) {
|
|
Function *Callee = CI->getCalledFunction();
|
|
FunctionType *FT = Callee->getFunctionType();
|
|
if (Value *V = optimizeSPrintFString(CI, B)) {
|
|
return V;
|
|
}
|
|
|
|
// sprintf(str, format, ...) -> siprintf(str, format, ...) if no floating
|
|
// point arguments.
|
|
if (TLI->has(LibFunc_siprintf) && !callHasFloatingPointArgument(CI)) {
|
|
Module *M = B.GetInsertBlock()->getParent()->getParent();
|
|
FunctionCallee SIPrintFFn =
|
|
M->getOrInsertFunction("siprintf", FT, Callee->getAttributes());
|
|
CallInst *New = cast<CallInst>(CI->clone());
|
|
New->setCalledFunction(SIPrintFFn);
|
|
B.Insert(New);
|
|
return New;
|
|
}
|
|
|
|
// sprintf(str, format, ...) -> __small_sprintf(str, format, ...) if no 128-bit
|
|
// floating point arguments.
|
|
if (TLI->has(LibFunc_small_sprintf) && !callHasFP128Argument(CI)) {
|
|
Module *M = B.GetInsertBlock()->getParent()->getParent();
|
|
auto SmallSPrintFFn =
|
|
M->getOrInsertFunction(TLI->getName(LibFunc_small_sprintf),
|
|
FT, Callee->getAttributes());
|
|
CallInst *New = cast<CallInst>(CI->clone());
|
|
New->setCalledFunction(SmallSPrintFFn);
|
|
B.Insert(New);
|
|
return New;
|
|
}
|
|
|
|
annotateNonNullBasedOnAccess(CI, {0, 1});
|
|
return nullptr;
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeSnPrintFString(CallInst *CI,
|
|
IRBuilderBase &B) {
|
|
// Check for size
|
|
ConstantInt *Size = dyn_cast<ConstantInt>(CI->getArgOperand(1));
|
|
if (!Size)
|
|
return nullptr;
|
|
|
|
uint64_t N = Size->getZExtValue();
|
|
// Check for a fixed format string.
|
|
StringRef FormatStr;
|
|
if (!getConstantStringInfo(CI->getArgOperand(2), FormatStr))
|
|
return nullptr;
|
|
|
|
// If we just have a format string (nothing else crazy) transform it.
|
|
if (CI->getNumArgOperands() == 3) {
|
|
// Make sure there's no % in the constant array. We could try to handle
|
|
// %% -> % in the future if we cared.
|
|
if (FormatStr.find('%') != StringRef::npos)
|
|
return nullptr; // we found a format specifier, bail out.
|
|
|
|
if (N == 0)
|
|
return ConstantInt::get(CI->getType(), FormatStr.size());
|
|
else if (N < FormatStr.size() + 1)
|
|
return nullptr;
|
|
|
|
// snprintf(dst, size, fmt) -> llvm.memcpy(align 1 dst, align 1 fmt,
|
|
// strlen(fmt)+1)
|
|
B.CreateMemCpy(
|
|
CI->getArgOperand(0), Align(1), CI->getArgOperand(2), Align(1),
|
|
ConstantInt::get(DL.getIntPtrType(CI->getContext()),
|
|
FormatStr.size() + 1)); // Copy the null byte.
|
|
return ConstantInt::get(CI->getType(), FormatStr.size());
|
|
}
|
|
|
|
// The remaining optimizations require the format string to be "%s" or "%c"
|
|
// and have an extra operand.
|
|
if (FormatStr.size() == 2 && FormatStr[0] == '%' &&
|
|
CI->getNumArgOperands() == 4) {
|
|
|
|
// Decode the second character of the format string.
|
|
if (FormatStr[1] == 'c') {
|
|
if (N == 0)
|
|
return ConstantInt::get(CI->getType(), 1);
|
|
else if (N == 1)
|
|
return nullptr;
|
|
|
|
// snprintf(dst, size, "%c", chr) --> *(i8*)dst = chr; *((i8*)dst+1) = 0
|
|
if (!CI->getArgOperand(3)->getType()->isIntegerTy())
|
|
return nullptr;
|
|
Value *V = B.CreateTrunc(CI->getArgOperand(3), B.getInt8Ty(), "char");
|
|
Value *Ptr = castToCStr(CI->getArgOperand(0), B);
|
|
B.CreateStore(V, Ptr);
|
|
Ptr = B.CreateGEP(B.getInt8Ty(), Ptr, B.getInt32(1), "nul");
|
|
B.CreateStore(B.getInt8(0), Ptr);
|
|
|
|
return ConstantInt::get(CI->getType(), 1);
|
|
}
|
|
|
|
if (FormatStr[1] == 's') {
|
|
// snprintf(dest, size, "%s", str) to llvm.memcpy(dest, str, len+1, 1)
|
|
StringRef Str;
|
|
if (!getConstantStringInfo(CI->getArgOperand(3), Str))
|
|
return nullptr;
|
|
|
|
if (N == 0)
|
|
return ConstantInt::get(CI->getType(), Str.size());
|
|
else if (N < Str.size() + 1)
|
|
return nullptr;
|
|
|
|
B.CreateMemCpy(CI->getArgOperand(0), Align(1), CI->getArgOperand(3),
|
|
Align(1), ConstantInt::get(CI->getType(), Str.size() + 1));
|
|
|
|
// The snprintf result is the unincremented number of bytes in the string.
|
|
return ConstantInt::get(CI->getType(), Str.size());
|
|
}
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeSnPrintF(CallInst *CI, IRBuilderBase &B) {
|
|
if (Value *V = optimizeSnPrintFString(CI, B)) {
|
|
return V;
|
|
}
|
|
|
|
if (isKnownNonZero(CI->getOperand(1), DL))
|
|
annotateNonNullBasedOnAccess(CI, 0);
|
|
return nullptr;
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeFPrintFString(CallInst *CI,
|
|
IRBuilderBase &B) {
|
|
optimizeErrorReporting(CI, B, 0);
|
|
|
|
// All the optimizations depend on the format string.
|
|
StringRef FormatStr;
|
|
if (!getConstantStringInfo(CI->getArgOperand(1), FormatStr))
|
|
return nullptr;
|
|
|
|
// Do not do any of the following transformations if the fprintf return
|
|
// value is used, in general the fprintf return value is not compatible
|
|
// with fwrite(), fputc() or fputs().
|
|
if (!CI->use_empty())
|
|
return nullptr;
|
|
|
|
// fprintf(F, "foo") --> fwrite("foo", 3, 1, F)
|
|
if (CI->getNumArgOperands() == 2) {
|
|
// Could handle %% -> % if we cared.
|
|
if (FormatStr.find('%') != StringRef::npos)
|
|
return nullptr; // We found a format specifier.
|
|
|
|
return emitFWrite(
|
|
CI->getArgOperand(1),
|
|
ConstantInt::get(DL.getIntPtrType(CI->getContext()), FormatStr.size()),
|
|
CI->getArgOperand(0), B, DL, TLI);
|
|
}
|
|
|
|
// The remaining optimizations require the format string to be "%s" or "%c"
|
|
// and have an extra operand.
|
|
if (FormatStr.size() != 2 || FormatStr[0] != '%' ||
|
|
CI->getNumArgOperands() < 3)
|
|
return nullptr;
|
|
|
|
// Decode the second character of the format string.
|
|
if (FormatStr[1] == 'c') {
|
|
// fprintf(F, "%c", chr) --> fputc(chr, F)
|
|
if (!CI->getArgOperand(2)->getType()->isIntegerTy())
|
|
return nullptr;
|
|
return emitFPutC(CI->getArgOperand(2), CI->getArgOperand(0), B, TLI);
|
|
}
|
|
|
|
if (FormatStr[1] == 's') {
|
|
// fprintf(F, "%s", str) --> fputs(str, F)
|
|
if (!CI->getArgOperand(2)->getType()->isPointerTy())
|
|
return nullptr;
|
|
return emitFPutS(CI->getArgOperand(2), CI->getArgOperand(0), B, TLI);
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeFPrintF(CallInst *CI, IRBuilderBase &B) {
|
|
Function *Callee = CI->getCalledFunction();
|
|
FunctionType *FT = Callee->getFunctionType();
|
|
if (Value *V = optimizeFPrintFString(CI, B)) {
|
|
return V;
|
|
}
|
|
|
|
// fprintf(stream, format, ...) -> fiprintf(stream, format, ...) if no
|
|
// floating point arguments.
|
|
if (TLI->has(LibFunc_fiprintf) && !callHasFloatingPointArgument(CI)) {
|
|
Module *M = B.GetInsertBlock()->getParent()->getParent();
|
|
FunctionCallee FIPrintFFn =
|
|
M->getOrInsertFunction("fiprintf", FT, Callee->getAttributes());
|
|
CallInst *New = cast<CallInst>(CI->clone());
|
|
New->setCalledFunction(FIPrintFFn);
|
|
B.Insert(New);
|
|
return New;
|
|
}
|
|
|
|
// fprintf(stream, format, ...) -> __small_fprintf(stream, format, ...) if no
|
|
// 128-bit floating point arguments.
|
|
if (TLI->has(LibFunc_small_fprintf) && !callHasFP128Argument(CI)) {
|
|
Module *M = B.GetInsertBlock()->getParent()->getParent();
|
|
auto SmallFPrintFFn =
|
|
M->getOrInsertFunction(TLI->getName(LibFunc_small_fprintf),
|
|
FT, Callee->getAttributes());
|
|
CallInst *New = cast<CallInst>(CI->clone());
|
|
New->setCalledFunction(SmallFPrintFFn);
|
|
B.Insert(New);
|
|
return New;
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeFWrite(CallInst *CI, IRBuilderBase &B) {
|
|
optimizeErrorReporting(CI, B, 3);
|
|
|
|
// Get the element size and count.
|
|
ConstantInt *SizeC = dyn_cast<ConstantInt>(CI->getArgOperand(1));
|
|
ConstantInt *CountC = dyn_cast<ConstantInt>(CI->getArgOperand(2));
|
|
if (SizeC && CountC) {
|
|
uint64_t Bytes = SizeC->getZExtValue() * CountC->getZExtValue();
|
|
|
|
// If this is writing zero records, remove the call (it's a noop).
|
|
if (Bytes == 0)
|
|
return ConstantInt::get(CI->getType(), 0);
|
|
|
|
// If this is writing one byte, turn it into fputc.
|
|
// This optimisation is only valid, if the return value is unused.
|
|
if (Bytes == 1 && CI->use_empty()) { // fwrite(S,1,1,F) -> fputc(S[0],F)
|
|
Value *Char = B.CreateLoad(B.getInt8Ty(),
|
|
castToCStr(CI->getArgOperand(0), B), "char");
|
|
Value *NewCI = emitFPutC(Char, CI->getArgOperand(3), B, TLI);
|
|
return NewCI ? ConstantInt::get(CI->getType(), 1) : nullptr;
|
|
}
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeFPuts(CallInst *CI, IRBuilderBase &B) {
|
|
optimizeErrorReporting(CI, B, 1);
|
|
|
|
// Don't rewrite fputs to fwrite when optimising for size because fwrite
|
|
// requires more arguments and thus extra MOVs are required.
|
|
bool OptForSize = CI->getFunction()->hasOptSize() ||
|
|
llvm::shouldOptimizeForSize(CI->getParent(), PSI, BFI,
|
|
PGSOQueryType::IRPass);
|
|
if (OptForSize)
|
|
return nullptr;
|
|
|
|
// We can't optimize if return value is used.
|
|
if (!CI->use_empty())
|
|
return nullptr;
|
|
|
|
// fputs(s,F) --> fwrite(s,strlen(s),1,F)
|
|
uint64_t Len = GetStringLength(CI->getArgOperand(0));
|
|
if (!Len)
|
|
return nullptr;
|
|
|
|
// Known to have no uses (see above).
|
|
return emitFWrite(
|
|
CI->getArgOperand(0),
|
|
ConstantInt::get(DL.getIntPtrType(CI->getContext()), Len - 1),
|
|
CI->getArgOperand(1), B, DL, TLI);
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizePuts(CallInst *CI, IRBuilderBase &B) {
|
|
annotateNonNullBasedOnAccess(CI, 0);
|
|
if (!CI->use_empty())
|
|
return nullptr;
|
|
|
|
// Check for a constant string.
|
|
// puts("") -> putchar('\n')
|
|
StringRef Str;
|
|
if (getConstantStringInfo(CI->getArgOperand(0), Str) && Str.empty())
|
|
return emitPutChar(B.getInt32('\n'), B, TLI);
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeBCopy(CallInst *CI, IRBuilderBase &B) {
|
|
// bcopy(src, dst, n) -> llvm.memmove(dst, src, n)
|
|
return B.CreateMemMove(CI->getArgOperand(1), Align(1), CI->getArgOperand(0),
|
|
Align(1), CI->getArgOperand(2));
|
|
}
|
|
|
|
bool LibCallSimplifier::hasFloatVersion(StringRef FuncName) {
|
|
LibFunc Func;
|
|
SmallString<20> FloatFuncName = FuncName;
|
|
FloatFuncName += 'f';
|
|
if (TLI->getLibFunc(FloatFuncName, Func))
|
|
return TLI->has(Func);
|
|
return false;
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeStringMemoryLibCall(CallInst *CI,
|
|
IRBuilderBase &Builder) {
|
|
LibFunc Func;
|
|
Function *Callee = CI->getCalledFunction();
|
|
// Check for string/memory library functions.
|
|
if (TLI->getLibFunc(*Callee, Func) && TLI->has(Func)) {
|
|
// Make sure we never change the calling convention.
|
|
assert((ignoreCallingConv(Func) ||
|
|
isCallingConvCCompatible(CI)) &&
|
|
"Optimizing string/memory libcall would change the calling convention");
|
|
switch (Func) {
|
|
case LibFunc_strcat:
|
|
return optimizeStrCat(CI, Builder);
|
|
case LibFunc_strncat:
|
|
return optimizeStrNCat(CI, Builder);
|
|
case LibFunc_strchr:
|
|
return optimizeStrChr(CI, Builder);
|
|
case LibFunc_strrchr:
|
|
return optimizeStrRChr(CI, Builder);
|
|
case LibFunc_strcmp:
|
|
return optimizeStrCmp(CI, Builder);
|
|
case LibFunc_strncmp:
|
|
return optimizeStrNCmp(CI, Builder);
|
|
case LibFunc_strcpy:
|
|
return optimizeStrCpy(CI, Builder);
|
|
case LibFunc_stpcpy:
|
|
return optimizeStpCpy(CI, Builder);
|
|
case LibFunc_strncpy:
|
|
return optimizeStrNCpy(CI, Builder);
|
|
case LibFunc_strlen:
|
|
return optimizeStrLen(CI, Builder);
|
|
case LibFunc_strpbrk:
|
|
return optimizeStrPBrk(CI, Builder);
|
|
case LibFunc_strndup:
|
|
return optimizeStrNDup(CI, Builder);
|
|
case LibFunc_strtol:
|
|
case LibFunc_strtod:
|
|
case LibFunc_strtof:
|
|
case LibFunc_strtoul:
|
|
case LibFunc_strtoll:
|
|
case LibFunc_strtold:
|
|
case LibFunc_strtoull:
|
|
return optimizeStrTo(CI, Builder);
|
|
case LibFunc_strspn:
|
|
return optimizeStrSpn(CI, Builder);
|
|
case LibFunc_strcspn:
|
|
return optimizeStrCSpn(CI, Builder);
|
|
case LibFunc_strstr:
|
|
return optimizeStrStr(CI, Builder);
|
|
case LibFunc_memchr:
|
|
return optimizeMemChr(CI, Builder);
|
|
case LibFunc_memrchr:
|
|
return optimizeMemRChr(CI, Builder);
|
|
case LibFunc_bcmp:
|
|
return optimizeBCmp(CI, Builder);
|
|
case LibFunc_memcmp:
|
|
return optimizeMemCmp(CI, Builder);
|
|
case LibFunc_memcpy:
|
|
return optimizeMemCpy(CI, Builder);
|
|
case LibFunc_memccpy:
|
|
return optimizeMemCCpy(CI, Builder);
|
|
case LibFunc_mempcpy:
|
|
return optimizeMemPCpy(CI, Builder);
|
|
case LibFunc_memmove:
|
|
return optimizeMemMove(CI, Builder);
|
|
case LibFunc_memset:
|
|
return optimizeMemSet(CI, Builder);
|
|
case LibFunc_realloc:
|
|
return optimizeRealloc(CI, Builder);
|
|
case LibFunc_wcslen:
|
|
return optimizeWcslen(CI, Builder);
|
|
case LibFunc_bcopy:
|
|
return optimizeBCopy(CI, Builder);
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeFloatingPointLibCall(CallInst *CI,
|
|
LibFunc Func,
|
|
IRBuilderBase &Builder) {
|
|
// Don't optimize calls that require strict floating point semantics.
|
|
if (CI->isStrictFP())
|
|
return nullptr;
|
|
|
|
if (Value *V = optimizeTrigReflections(CI, Func, Builder))
|
|
return V;
|
|
|
|
switch (Func) {
|
|
case LibFunc_sinpif:
|
|
case LibFunc_sinpi:
|
|
case LibFunc_cospif:
|
|
case LibFunc_cospi:
|
|
return optimizeSinCosPi(CI, Builder);
|
|
case LibFunc_powf:
|
|
case LibFunc_pow:
|
|
case LibFunc_powl:
|
|
return optimizePow(CI, Builder);
|
|
case LibFunc_exp2l:
|
|
case LibFunc_exp2:
|
|
case LibFunc_exp2f:
|
|
return optimizeExp2(CI, Builder);
|
|
case LibFunc_fabsf:
|
|
case LibFunc_fabs:
|
|
case LibFunc_fabsl:
|
|
return replaceUnaryCall(CI, Builder, Intrinsic::fabs);
|
|
case LibFunc_sqrtf:
|
|
case LibFunc_sqrt:
|
|
case LibFunc_sqrtl:
|
|
return optimizeSqrt(CI, Builder);
|
|
case LibFunc_logf:
|
|
case LibFunc_log:
|
|
case LibFunc_logl:
|
|
case LibFunc_log10f:
|
|
case LibFunc_log10:
|
|
case LibFunc_log10l:
|
|
case LibFunc_log1pf:
|
|
case LibFunc_log1p:
|
|
case LibFunc_log1pl:
|
|
case LibFunc_log2f:
|
|
case LibFunc_log2:
|
|
case LibFunc_log2l:
|
|
case LibFunc_logbf:
|
|
case LibFunc_logb:
|
|
case LibFunc_logbl:
|
|
return optimizeLog(CI, Builder);
|
|
case LibFunc_tan:
|
|
case LibFunc_tanf:
|
|
case LibFunc_tanl:
|
|
return optimizeTan(CI, Builder);
|
|
case LibFunc_ceil:
|
|
return replaceUnaryCall(CI, Builder, Intrinsic::ceil);
|
|
case LibFunc_floor:
|
|
return replaceUnaryCall(CI, Builder, Intrinsic::floor);
|
|
case LibFunc_round:
|
|
return replaceUnaryCall(CI, Builder, Intrinsic::round);
|
|
case LibFunc_roundeven:
|
|
return replaceUnaryCall(CI, Builder, Intrinsic::roundeven);
|
|
case LibFunc_nearbyint:
|
|
return replaceUnaryCall(CI, Builder, Intrinsic::nearbyint);
|
|
case LibFunc_rint:
|
|
return replaceUnaryCall(CI, Builder, Intrinsic::rint);
|
|
case LibFunc_trunc:
|
|
return replaceUnaryCall(CI, Builder, Intrinsic::trunc);
|
|
case LibFunc_acos:
|
|
case LibFunc_acosh:
|
|
case LibFunc_asin:
|
|
case LibFunc_asinh:
|
|
case LibFunc_atan:
|
|
case LibFunc_atanh:
|
|
case LibFunc_cbrt:
|
|
case LibFunc_cosh:
|
|
case LibFunc_exp:
|
|
case LibFunc_exp10:
|
|
case LibFunc_expm1:
|
|
case LibFunc_cos:
|
|
case LibFunc_sin:
|
|
case LibFunc_sinh:
|
|
case LibFunc_tanh:
|
|
if (UnsafeFPShrink && hasFloatVersion(CI->getCalledFunction()->getName()))
|
|
return optimizeUnaryDoubleFP(CI, Builder, true);
|
|
return nullptr;
|
|
case LibFunc_copysign:
|
|
if (hasFloatVersion(CI->getCalledFunction()->getName()))
|
|
return optimizeBinaryDoubleFP(CI, Builder);
|
|
return nullptr;
|
|
case LibFunc_fminf:
|
|
case LibFunc_fmin:
|
|
case LibFunc_fminl:
|
|
case LibFunc_fmaxf:
|
|
case LibFunc_fmax:
|
|
case LibFunc_fmaxl:
|
|
return optimizeFMinFMax(CI, Builder);
|
|
case LibFunc_cabs:
|
|
case LibFunc_cabsf:
|
|
case LibFunc_cabsl:
|
|
return optimizeCAbs(CI, Builder);
|
|
default:
|
|
return nullptr;
|
|
}
|
|
}
|
|
|
|
Value *LibCallSimplifier::optimizeCall(CallInst *CI, IRBuilderBase &Builder) {
|
|
// TODO: Split out the code below that operates on FP calls so that
|
|
// we can all non-FP calls with the StrictFP attribute to be
|
|
// optimized.
|
|
if (CI->isNoBuiltin())
|
|
return nullptr;
|
|
|
|
LibFunc Func;
|
|
Function *Callee = CI->getCalledFunction();
|
|
bool isCallingConvC = isCallingConvCCompatible(CI);
|
|
|
|
SmallVector<OperandBundleDef, 2> OpBundles;
|
|
CI->getOperandBundlesAsDefs(OpBundles);
|
|
|
|
IRBuilderBase::OperandBundlesGuard Guard(Builder);
|
|
Builder.setDefaultOperandBundles(OpBundles);
|
|
|
|
// Command-line parameter overrides instruction attribute.
|
|
// This can't be moved to optimizeFloatingPointLibCall() because it may be
|
|
// used by the intrinsic optimizations.
|
|
if (EnableUnsafeFPShrink.getNumOccurrences() > 0)
|
|
UnsafeFPShrink = EnableUnsafeFPShrink;
|
|
else if (isa<FPMathOperator>(CI) && CI->isFast())
|
|
UnsafeFPShrink = true;
|
|
|
|
// First, check for intrinsics.
|
|
if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(CI)) {
|
|
if (!isCallingConvC)
|
|
return nullptr;
|
|
// The FP intrinsics have corresponding constrained versions so we don't
|
|
// need to check for the StrictFP attribute here.
|
|
switch (II->getIntrinsicID()) {
|
|
case Intrinsic::pow:
|
|
return optimizePow(CI, Builder);
|
|
case Intrinsic::exp2:
|
|
return optimizeExp2(CI, Builder);
|
|
case Intrinsic::log:
|
|
case Intrinsic::log2:
|
|
case Intrinsic::log10:
|
|
return optimizeLog(CI, Builder);
|
|
case Intrinsic::sqrt:
|
|
return optimizeSqrt(CI, Builder);
|
|
// TODO: Use foldMallocMemset() with memset intrinsic.
|
|
case Intrinsic::memset:
|
|
return optimizeMemSet(CI, Builder);
|
|
case Intrinsic::memcpy:
|
|
return optimizeMemCpy(CI, Builder);
|
|
case Intrinsic::memmove:
|
|
return optimizeMemMove(CI, Builder);
|
|
default:
|
|
return nullptr;
|
|
}
|
|
}
|
|
|
|
// Also try to simplify calls to fortified library functions.
|
|
if (Value *SimplifiedFortifiedCI =
|
|
FortifiedSimplifier.optimizeCall(CI, Builder)) {
|
|
// Try to further simplify the result.
|
|
CallInst *SimplifiedCI = dyn_cast<CallInst>(SimplifiedFortifiedCI);
|
|
if (SimplifiedCI && SimplifiedCI->getCalledFunction()) {
|
|
// Ensure that SimplifiedCI's uses are complete, since some calls have
|
|
// their uses analyzed.
|
|
replaceAllUsesWith(CI, SimplifiedCI);
|
|
|
|
// Set insertion point to SimplifiedCI to guarantee we reach all uses
|
|
// we might replace later on.
|
|
IRBuilderBase::InsertPointGuard Guard(Builder);
|
|
Builder.SetInsertPoint(SimplifiedCI);
|
|
if (Value *V = optimizeStringMemoryLibCall(SimplifiedCI, Builder)) {
|
|
// If we were able to further simplify, remove the now redundant call.
|
|
substituteInParent(SimplifiedCI, V);
|
|
return V;
|
|
}
|
|
}
|
|
return SimplifiedFortifiedCI;
|
|
}
|
|
|
|
// Then check for known library functions.
|
|
if (TLI->getLibFunc(*Callee, Func) && TLI->has(Func)) {
|
|
// We never change the calling convention.
|
|
if (!ignoreCallingConv(Func) && !isCallingConvC)
|
|
return nullptr;
|
|
if (Value *V = optimizeStringMemoryLibCall(CI, Builder))
|
|
return V;
|
|
if (Value *V = optimizeFloatingPointLibCall(CI, Func, Builder))
|
|
return V;
|
|
switch (Func) {
|
|
case LibFunc_ffs:
|
|
case LibFunc_ffsl:
|
|
case LibFunc_ffsll:
|
|
return optimizeFFS(CI, Builder);
|
|
case LibFunc_fls:
|
|
case LibFunc_flsl:
|
|
case LibFunc_flsll:
|
|
return optimizeFls(CI, Builder);
|
|
case LibFunc_abs:
|
|
case LibFunc_labs:
|
|
case LibFunc_llabs:
|
|
return optimizeAbs(CI, Builder);
|
|
case LibFunc_isdigit:
|
|
return optimizeIsDigit(CI, Builder);
|
|
case LibFunc_isascii:
|
|
return optimizeIsAscii(CI, Builder);
|
|
case LibFunc_toascii:
|
|
return optimizeToAscii(CI, Builder);
|
|
case LibFunc_atoi:
|
|
case LibFunc_atol:
|
|
case LibFunc_atoll:
|
|
return optimizeAtoi(CI, Builder);
|
|
case LibFunc_strtol:
|
|
case LibFunc_strtoll:
|
|
return optimizeStrtol(CI, Builder);
|
|
case LibFunc_printf:
|
|
return optimizePrintF(CI, Builder);
|
|
case LibFunc_sprintf:
|
|
return optimizeSPrintF(CI, Builder);
|
|
case LibFunc_snprintf:
|
|
return optimizeSnPrintF(CI, Builder);
|
|
case LibFunc_fprintf:
|
|
return optimizeFPrintF(CI, Builder);
|
|
case LibFunc_fwrite:
|
|
return optimizeFWrite(CI, Builder);
|
|
case LibFunc_fputs:
|
|
return optimizeFPuts(CI, Builder);
|
|
case LibFunc_puts:
|
|
return optimizePuts(CI, Builder);
|
|
case LibFunc_perror:
|
|
return optimizeErrorReporting(CI, Builder);
|
|
case LibFunc_vfprintf:
|
|
case LibFunc_fiprintf:
|
|
return optimizeErrorReporting(CI, Builder, 0);
|
|
default:
|
|
return nullptr;
|
|
}
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
LibCallSimplifier::LibCallSimplifier(
|
|
const DataLayout &DL, const TargetLibraryInfo *TLI,
|
|
OptimizationRemarkEmitter &ORE,
|
|
BlockFrequencyInfo *BFI, ProfileSummaryInfo *PSI,
|
|
function_ref<void(Instruction *, Value *)> Replacer,
|
|
function_ref<void(Instruction *)> Eraser)
|
|
: FortifiedSimplifier(TLI), DL(DL), TLI(TLI), ORE(ORE), BFI(BFI), PSI(PSI),
|
|
UnsafeFPShrink(false), Replacer(Replacer), Eraser(Eraser) {}
|
|
|
|
void LibCallSimplifier::replaceAllUsesWith(Instruction *I, Value *With) {
|
|
// Indirect through the replacer used in this instance.
|
|
Replacer(I, With);
|
|
}
|
|
|
|
void LibCallSimplifier::eraseFromParent(Instruction *I) {
|
|
Eraser(I);
|
|
}
|
|
|
|
// TODO:
|
|
// Additional cases that we need to add to this file:
|
|
//
|
|
// cbrt:
|
|
// * cbrt(expN(X)) -> expN(x/3)
|
|
// * cbrt(sqrt(x)) -> pow(x,1/6)
|
|
// * cbrt(cbrt(x)) -> pow(x,1/9)
|
|
//
|
|
// exp, expf, expl:
|
|
// * exp(log(x)) -> x
|
|
//
|
|
// log, logf, logl:
|
|
// * log(exp(x)) -> x
|
|
// * log(exp(y)) -> y*log(e)
|
|
// * log(exp10(y)) -> y*log(10)
|
|
// * log(sqrt(x)) -> 0.5*log(x)
|
|
//
|
|
// pow, powf, powl:
|
|
// * pow(sqrt(x),y) -> pow(x,y*0.5)
|
|
// * pow(pow(x,y),z)-> pow(x,y*z)
|
|
//
|
|
// signbit:
|
|
// * signbit(cnst) -> cnst'
|
|
// * signbit(nncst) -> 0 (if pstv is a non-negative constant)
|
|
//
|
|
// sqrt, sqrtf, sqrtl:
|
|
// * sqrt(expN(x)) -> expN(x*0.5)
|
|
// * sqrt(Nroot(x)) -> pow(x,1/(2*N))
|
|
// * sqrt(pow(x,y)) -> pow(|x|,y*0.5)
|
|
//
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Fortified Library Call Optimizations
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
bool
|
|
FortifiedLibCallSimplifier::isFortifiedCallFoldable(CallInst *CI,
|
|
unsigned ObjSizeOp,
|
|
Optional<unsigned> SizeOp,
|
|
Optional<unsigned> StrOp,
|
|
Optional<unsigned> FlagOp) {
|
|
// If this function takes a flag argument, the implementation may use it to
|
|
// perform extra checks. Don't fold into the non-checking variant.
|
|
if (FlagOp) {
|
|
ConstantInt *Flag = dyn_cast<ConstantInt>(CI->getArgOperand(*FlagOp));
|
|
if (!Flag || !Flag->isZero())
|
|
return false;
|
|
}
|
|
|
|
if (SizeOp && CI->getArgOperand(ObjSizeOp) == CI->getArgOperand(*SizeOp))
|
|
return true;
|
|
|
|
if (ConstantInt *ObjSizeCI =
|
|
dyn_cast<ConstantInt>(CI->getArgOperand(ObjSizeOp))) {
|
|
if (ObjSizeCI->isMinusOne())
|
|
return true;
|
|
// If the object size wasn't -1 (unknown), bail out if we were asked to.
|
|
if (OnlyLowerUnknownSize)
|
|
return false;
|
|
if (StrOp) {
|
|
uint64_t Len = GetStringLength(CI->getArgOperand(*StrOp));
|
|
// If the length is 0 we don't know how long it is and so we can't
|
|
// remove the check.
|
|
if (Len)
|
|
annotateDereferenceableBytes(CI, *StrOp, Len);
|
|
else
|
|
return false;
|
|
return ObjSizeCI->getZExtValue() >= Len;
|
|
}
|
|
|
|
if (SizeOp) {
|
|
if (ConstantInt *SizeCI =
|
|
dyn_cast<ConstantInt>(CI->getArgOperand(*SizeOp)))
|
|
return ObjSizeCI->getZExtValue() >= SizeCI->getZExtValue();
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
|
|
Value *FortifiedLibCallSimplifier::optimizeMemCpyChk(CallInst *CI,
|
|
IRBuilderBase &B) {
|
|
if (isFortifiedCallFoldable(CI, 3, 2)) {
|
|
CallInst *NewCI =
|
|
B.CreateMemCpy(CI->getArgOperand(0), Align(1), CI->getArgOperand(1),
|
|
Align(1), CI->getArgOperand(2));
|
|
NewCI->setAttributes(CI->getAttributes());
|
|
NewCI->removeAttributes(AttributeList::ReturnIndex,
|
|
AttributeFuncs::typeIncompatible(NewCI->getType()));
|
|
return CI->getArgOperand(0);
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
Value *FortifiedLibCallSimplifier::optimizeMemMoveChk(CallInst *CI,
|
|
IRBuilderBase &B) {
|
|
if (isFortifiedCallFoldable(CI, 3, 2)) {
|
|
CallInst *NewCI =
|
|
B.CreateMemMove(CI->getArgOperand(0), Align(1), CI->getArgOperand(1),
|
|
Align(1), CI->getArgOperand(2));
|
|
NewCI->setAttributes(CI->getAttributes());
|
|
NewCI->removeAttributes(AttributeList::ReturnIndex,
|
|
AttributeFuncs::typeIncompatible(NewCI->getType()));
|
|
return CI->getArgOperand(0);
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
Value *FortifiedLibCallSimplifier::optimizeMemSetChk(CallInst *CI,
|
|
IRBuilderBase &B) {
|
|
// TODO: Try foldMallocMemset() here.
|
|
|
|
if (isFortifiedCallFoldable(CI, 3, 2)) {
|
|
Value *Val = B.CreateIntCast(CI->getArgOperand(1), B.getInt8Ty(), false);
|
|
CallInst *NewCI = B.CreateMemSet(CI->getArgOperand(0), Val,
|
|
CI->getArgOperand(2), Align(1));
|
|
NewCI->setAttributes(CI->getAttributes());
|
|
NewCI->removeAttributes(AttributeList::ReturnIndex,
|
|
AttributeFuncs::typeIncompatible(NewCI->getType()));
|
|
return CI->getArgOperand(0);
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
Value *FortifiedLibCallSimplifier::optimizeMemPCpyChk(CallInst *CI,
|
|
IRBuilderBase &B) {
|
|
const DataLayout &DL = CI->getModule()->getDataLayout();
|
|
if (isFortifiedCallFoldable(CI, 3, 2))
|
|
if (Value *Call = emitMemPCpy(CI->getArgOperand(0), CI->getArgOperand(1),
|
|
CI->getArgOperand(2), B, DL, TLI)) {
|
|
CallInst *NewCI = cast<CallInst>(Call);
|
|
NewCI->setAttributes(CI->getAttributes());
|
|
NewCI->removeAttributes(
|
|
AttributeList::ReturnIndex,
|
|
AttributeFuncs::typeIncompatible(NewCI->getType()));
|
|
return NewCI;
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
Value *FortifiedLibCallSimplifier::optimizeStrpCpyChk(CallInst *CI,
|
|
IRBuilderBase &B,
|
|
LibFunc Func) {
|
|
const DataLayout &DL = CI->getModule()->getDataLayout();
|
|
Value *Dst = CI->getArgOperand(0), *Src = CI->getArgOperand(1),
|
|
*ObjSize = CI->getArgOperand(2);
|
|
|
|
// __stpcpy_chk(x,x,...) -> x+strlen(x)
|
|
if (Func == LibFunc_stpcpy_chk && !OnlyLowerUnknownSize && Dst == Src) {
|
|
Value *StrLen = emitStrLen(Src, B, DL, TLI);
|
|
return StrLen ? B.CreateInBoundsGEP(B.getInt8Ty(), Dst, StrLen) : nullptr;
|
|
}
|
|
|
|
// If a) we don't have any length information, or b) we know this will
|
|
// fit then just lower to a plain st[rp]cpy. Otherwise we'll keep our
|
|
// st[rp]cpy_chk call which may fail at runtime if the size is too long.
|
|
// TODO: It might be nice to get a maximum length out of the possible
|
|
// string lengths for varying.
|
|
if (isFortifiedCallFoldable(CI, 2, None, 1)) {
|
|
if (Func == LibFunc_strcpy_chk)
|
|
return emitStrCpy(Dst, Src, B, TLI);
|
|
else
|
|
return emitStpCpy(Dst, Src, B, TLI);
|
|
}
|
|
|
|
if (OnlyLowerUnknownSize)
|
|
return nullptr;
|
|
|
|
// Maybe we can stil fold __st[rp]cpy_chk to __memcpy_chk.
|
|
uint64_t Len = GetStringLength(Src);
|
|
if (Len)
|
|
annotateDereferenceableBytes(CI, 1, Len);
|
|
else
|
|
return nullptr;
|
|
|
|
Type *SizeTTy = DL.getIntPtrType(CI->getContext());
|
|
Value *LenV = ConstantInt::get(SizeTTy, Len);
|
|
Value *Ret = emitMemCpyChk(Dst, Src, LenV, ObjSize, B, DL, TLI);
|
|
// If the function was an __stpcpy_chk, and we were able to fold it into
|
|
// a __memcpy_chk, we still need to return the correct end pointer.
|
|
if (Ret && Func == LibFunc_stpcpy_chk)
|
|
return B.CreateGEP(B.getInt8Ty(), Dst, ConstantInt::get(SizeTTy, Len - 1));
|
|
return Ret;
|
|
}
|
|
|
|
Value *FortifiedLibCallSimplifier::optimizeStrLenChk(CallInst *CI,
|
|
IRBuilderBase &B) {
|
|
if (isFortifiedCallFoldable(CI, 1, None, 0))
|
|
return emitStrLen(CI->getArgOperand(0), B, CI->getModule()->getDataLayout(),
|
|
TLI);
|
|
return nullptr;
|
|
}
|
|
|
|
Value *FortifiedLibCallSimplifier::optimizeStrpNCpyChk(CallInst *CI,
|
|
IRBuilderBase &B,
|
|
LibFunc Func) {
|
|
if (isFortifiedCallFoldable(CI, 3, 2)) {
|
|
if (Func == LibFunc_strncpy_chk)
|
|
return emitStrNCpy(CI->getArgOperand(0), CI->getArgOperand(1),
|
|
CI->getArgOperand(2), B, TLI);
|
|
else
|
|
return emitStpNCpy(CI->getArgOperand(0), CI->getArgOperand(1),
|
|
CI->getArgOperand(2), B, TLI);
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
Value *FortifiedLibCallSimplifier::optimizeMemCCpyChk(CallInst *CI,
|
|
IRBuilderBase &B) {
|
|
if (isFortifiedCallFoldable(CI, 4, 3))
|
|
return emitMemCCpy(CI->getArgOperand(0), CI->getArgOperand(1),
|
|
CI->getArgOperand(2), CI->getArgOperand(3), B, TLI);
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
Value *FortifiedLibCallSimplifier::optimizeSNPrintfChk(CallInst *CI,
|
|
IRBuilderBase &B) {
|
|
if (isFortifiedCallFoldable(CI, 3, 1, None, 2)) {
|
|
SmallVector<Value *, 8> VariadicArgs(drop_begin(CI->args(), 5));
|
|
return emitSNPrintf(CI->getArgOperand(0), CI->getArgOperand(1),
|
|
CI->getArgOperand(4), VariadicArgs, B, TLI);
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
Value *FortifiedLibCallSimplifier::optimizeSPrintfChk(CallInst *CI,
|
|
IRBuilderBase &B) {
|
|
if (isFortifiedCallFoldable(CI, 2, None, None, 1)) {
|
|
SmallVector<Value *, 8> VariadicArgs(drop_begin(CI->args(), 4));
|
|
return emitSPrintf(CI->getArgOperand(0), CI->getArgOperand(3), VariadicArgs,
|
|
B, TLI);
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
Value *FortifiedLibCallSimplifier::optimizeStrCatChk(CallInst *CI,
|
|
IRBuilderBase &B) {
|
|
if (isFortifiedCallFoldable(CI, 2))
|
|
return emitStrCat(CI->getArgOperand(0), CI->getArgOperand(1), B, TLI);
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
Value *FortifiedLibCallSimplifier::optimizeStrLCat(CallInst *CI,
|
|
IRBuilderBase &B) {
|
|
if (isFortifiedCallFoldable(CI, 3))
|
|
return emitStrLCat(CI->getArgOperand(0), CI->getArgOperand(1),
|
|
CI->getArgOperand(2), B, TLI);
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
Value *FortifiedLibCallSimplifier::optimizeStrNCatChk(CallInst *CI,
|
|
IRBuilderBase &B) {
|
|
if (isFortifiedCallFoldable(CI, 3))
|
|
return emitStrNCat(CI->getArgOperand(0), CI->getArgOperand(1),
|
|
CI->getArgOperand(2), B, TLI);
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
Value *FortifiedLibCallSimplifier::optimizeStrLCpyChk(CallInst *CI,
|
|
IRBuilderBase &B) {
|
|
if (isFortifiedCallFoldable(CI, 3))
|
|
return emitStrLCpy(CI->getArgOperand(0), CI->getArgOperand(1),
|
|
CI->getArgOperand(2), B, TLI);
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
Value *FortifiedLibCallSimplifier::optimizeVSNPrintfChk(CallInst *CI,
|
|
IRBuilderBase &B) {
|
|
if (isFortifiedCallFoldable(CI, 3, 1, None, 2))
|
|
return emitVSNPrintf(CI->getArgOperand(0), CI->getArgOperand(1),
|
|
CI->getArgOperand(4), CI->getArgOperand(5), B, TLI);
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
Value *FortifiedLibCallSimplifier::optimizeVSPrintfChk(CallInst *CI,
|
|
IRBuilderBase &B) {
|
|
if (isFortifiedCallFoldable(CI, 2, None, None, 1))
|
|
return emitVSPrintf(CI->getArgOperand(0), CI->getArgOperand(3),
|
|
CI->getArgOperand(4), B, TLI);
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
Value *FortifiedLibCallSimplifier::optimizeCall(CallInst *CI,
|
|
IRBuilderBase &Builder) {
|
|
// FIXME: We shouldn't be changing "nobuiltin" or TLI unavailable calls here.
|
|
// Some clang users checked for _chk libcall availability using:
|
|
// __has_builtin(__builtin___memcpy_chk)
|
|
// When compiling with -fno-builtin, this is always true.
|
|
// When passing -ffreestanding/-mkernel, which both imply -fno-builtin, we
|
|
// end up with fortified libcalls, which isn't acceptable in a freestanding
|
|
// environment which only provides their non-fortified counterparts.
|
|
//
|
|
// Until we change clang and/or teach external users to check for availability
|
|
// differently, disregard the "nobuiltin" attribute and TLI::has.
|
|
//
|
|
// PR23093.
|
|
|
|
LibFunc Func;
|
|
Function *Callee = CI->getCalledFunction();
|
|
bool isCallingConvC = isCallingConvCCompatible(CI);
|
|
|
|
SmallVector<OperandBundleDef, 2> OpBundles;
|
|
CI->getOperandBundlesAsDefs(OpBundles);
|
|
|
|
IRBuilderBase::OperandBundlesGuard Guard(Builder);
|
|
Builder.setDefaultOperandBundles(OpBundles);
|
|
|
|
// First, check that this is a known library functions and that the prototype
|
|
// is correct.
|
|
if (!TLI->getLibFunc(*Callee, Func))
|
|
return nullptr;
|
|
|
|
// We never change the calling convention.
|
|
if (!ignoreCallingConv(Func) && !isCallingConvC)
|
|
return nullptr;
|
|
|
|
switch (Func) {
|
|
case LibFunc_memcpy_chk:
|
|
return optimizeMemCpyChk(CI, Builder);
|
|
case LibFunc_mempcpy_chk:
|
|
return optimizeMemPCpyChk(CI, Builder);
|
|
case LibFunc_memmove_chk:
|
|
return optimizeMemMoveChk(CI, Builder);
|
|
case LibFunc_memset_chk:
|
|
return optimizeMemSetChk(CI, Builder);
|
|
case LibFunc_stpcpy_chk:
|
|
case LibFunc_strcpy_chk:
|
|
return optimizeStrpCpyChk(CI, Builder, Func);
|
|
case LibFunc_strlen_chk:
|
|
return optimizeStrLenChk(CI, Builder);
|
|
case LibFunc_stpncpy_chk:
|
|
case LibFunc_strncpy_chk:
|
|
return optimizeStrpNCpyChk(CI, Builder, Func);
|
|
case LibFunc_memccpy_chk:
|
|
return optimizeMemCCpyChk(CI, Builder);
|
|
case LibFunc_snprintf_chk:
|
|
return optimizeSNPrintfChk(CI, Builder);
|
|
case LibFunc_sprintf_chk:
|
|
return optimizeSPrintfChk(CI, Builder);
|
|
case LibFunc_strcat_chk:
|
|
return optimizeStrCatChk(CI, Builder);
|
|
case LibFunc_strlcat_chk:
|
|
return optimizeStrLCat(CI, Builder);
|
|
case LibFunc_strncat_chk:
|
|
return optimizeStrNCatChk(CI, Builder);
|
|
case LibFunc_strlcpy_chk:
|
|
return optimizeStrLCpyChk(CI, Builder);
|
|
case LibFunc_vsnprintf_chk:
|
|
return optimizeVSNPrintfChk(CI, Builder);
|
|
case LibFunc_vsprintf_chk:
|
|
return optimizeVSPrintfChk(CI, Builder);
|
|
default:
|
|
break;
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
FortifiedLibCallSimplifier::FortifiedLibCallSimplifier(
|
|
const TargetLibraryInfo *TLI, bool OnlyLowerUnknownSize)
|
|
: TLI(TLI), OnlyLowerUnknownSize(OnlyLowerUnknownSize) {}
|