#include "llvm/Transforms/Utils/SimplifyLibCalls.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/StringMap.h"
+#include "llvm/ADT/Triple.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/IR/DataLayout.h"
+#include "llvm/IR/DiagnosticInfo.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Intrinsics.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/Module.h"
+#include "llvm/IR/PatternMatch.h"
#include "llvm/Support/Allocator.h"
-#include "llvm/Target/TargetLibraryInfo.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Analysis/TargetLibraryInfo.h"
#include "llvm/Transforms/Utils/BuildLibCalls.h"
+#include "llvm/Transforms/Utils/Local.h"
using namespace llvm;
+using namespace PatternMatch;
-/// This class is the abstract base class for the set of optimizations that
-/// corresponds to one library call.
-namespace {
-class LibCallOptimization {
-protected:
- Function *Caller;
- const DataLayout *TD;
- const TargetLibraryInfo *TLI;
- const LibCallSimplifier *LCS;
- LLVMContext* Context;
-public:
- LibCallOptimization() { }
- virtual ~LibCallOptimization() {}
-
- /// callOptimizer - This pure virtual method is implemented by base classes to
- /// do various optimizations. If this returns null then no transformation was
- /// performed. If it returns CI, then it transformed the call and CI is to be
- /// deleted. If it returns something else, replace CI with the new value and
- /// delete CI.
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B)
- =0;
-
- /// ignoreCallingConv - Returns false if this transformation could possibly
- /// change the calling convention.
- virtual bool ignoreCallingConv() { return false; }
-
- Value *optimizeCall(CallInst *CI, const DataLayout *TD,
- const TargetLibraryInfo *TLI,
- const LibCallSimplifier *LCS, IRBuilder<> &B) {
- Caller = CI->getParent()->getParent();
- this->TD = TD;
- this->TLI = TLI;
- this->LCS = LCS;
- if (CI->getCalledFunction())
- Context = &CI->getCalledFunction()->getContext();
+static cl::opt<bool>
+ ColdErrorCalls("error-reporting-is-cold", cl::init(true), cl::Hidden,
+ cl::desc("Treat error-reporting calls as cold"));
- // We never change the calling convention.
- if (!ignoreCallingConv() && CI->getCallingConv() != llvm::CallingConv::C)
- return NULL;
+static cl::opt<bool>
+ EnableUnsafeFPShrink("enable-double-float-shrink", cl::Hidden,
+ cl::init(false),
+ cl::desc("Enable unsafe double to float "
+ "shrinking for math lib calls"));
- return callOptimizer(CI->getCalledFunction(), CI, B);
- }
-};
//===----------------------------------------------------------------------===//
// Helper Functions
//===----------------------------------------------------------------------===//
+static bool ignoreCallingConv(LibFunc::Func Func) {
+ switch (Func) {
+ case LibFunc::abs:
+ case LibFunc::labs:
+ case LibFunc::llabs:
+ case LibFunc::strlen:
+ return true;
+ default:
+ return false;
+ }
+ llvm_unreachable("All cases should be covered in the switch.");
+}
+
/// isOnlyUsedInZeroEqualityComparison - Return true if it only matters that the
/// value is equal or not-equal to zero.
static bool isOnlyUsedInZeroEqualityComparison(Value *V) {
- for (Value::use_iterator UI = V->use_begin(), E = V->use_end();
- UI != E; ++UI) {
- if (ICmpInst *IC = dyn_cast<ICmpInst>(*UI))
+ for (User *U : V->users()) {
+ if (ICmpInst *IC = dyn_cast<ICmpInst>(U))
if (IC->isEquality())
if (Constant *C = dyn_cast<Constant>(IC->getOperand(1)))
if (C->isNullValue())
/// isOnlyUsedInEqualityComparison - Return true if it is only used in equality
/// comparisons with With.
static bool isOnlyUsedInEqualityComparison(Value *V, Value *With) {
- for (Value::use_iterator UI = V->use_begin(), E = V->use_end();
- UI != E; ++UI) {
- if (ICmpInst *IC = dyn_cast<ICmpInst>(*UI))
+ for (User *U : V->users()) {
+ if (ICmpInst *IC = dyn_cast<ICmpInst>(U))
if (IC->isEquality() && IC->getOperand(1) == With)
continue;
// Unknown instruction.
return false;
}
-//===----------------------------------------------------------------------===//
-// Fortified Library Call Optimizations
-//===----------------------------------------------------------------------===//
-
-struct FortifiedLibCallOptimization : public LibCallOptimization {
-protected:
- virtual bool isFoldable(unsigned SizeCIOp, unsigned SizeArgOp,
- bool isString) const = 0;
-};
-
-struct InstFortifiedLibCallOptimization : public FortifiedLibCallOptimization {
- CallInst *CI;
+/// \brief Check whether the overloaded unary floating point function
+/// corresponding to \a Ty is available.
+static bool hasUnaryFloatFn(const TargetLibraryInfo *TLI, Type *Ty,
+ LibFunc::Func DoubleFn, LibFunc::Func FloatFn,
+ LibFunc::Func LongDoubleFn) {
+ switch (Ty->getTypeID()) {
+ case Type::FloatTyID:
+ return TLI->has(FloatFn);
+ case Type::DoubleTyID:
+ return TLI->has(DoubleFn);
+ default:
+ return TLI->has(LongDoubleFn);
+ }
+}
- bool isFoldable(unsigned SizeCIOp, unsigned SizeArgOp, bool isString) const {
- if (CI->getArgOperand(SizeCIOp) == CI->getArgOperand(SizeArgOp))
+/// \brief Check whether we can use unsafe floating point math for
+/// the function passed as input.
+static bool canUseUnsafeFPMath(Function *F) {
+
+ // FIXME: For finer-grain optimization, we need intrinsics to have the same
+ // fast-math flag decorations that are applied to FP instructions. For now,
+ // we have to rely on the function-level unsafe-fp-math attribute to do this
+ // optimization because there's no other way to express that the sqrt can be
+ // reassociated.
+ if (F->hasFnAttribute("unsafe-fp-math")) {
+ Attribute Attr = F->getFnAttribute("unsafe-fp-math");
+ if (Attr.getValueAsString() == "true")
return true;
- if (ConstantInt *SizeCI =
- dyn_cast<ConstantInt>(CI->getArgOperand(SizeCIOp))) {
- if (SizeCI->isAllOnesValue())
- return true;
- if (isString) {
- uint64_t Len = GetStringLength(CI->getArgOperand(SizeArgOp));
- // If the length is 0 we don't know how long it is and so we can't
- // remove the check.
- if (Len == 0) return false;
- return SizeCI->getZExtValue() >= Len;
- }
- if (ConstantInt *Arg = dyn_cast<ConstantInt>(
- CI->getArgOperand(SizeArgOp)))
- return SizeCI->getZExtValue() >= Arg->getZExtValue();
- }
- return false;
}
-};
-
-struct MemCpyChkOpt : public InstFortifiedLibCallOptimization {
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- this->CI = CI;
- FunctionType *FT = Callee->getFunctionType();
- LLVMContext &Context = CI->getParent()->getContext();
-
- // Check if this has the right signature.
- if (FT->getNumParams() != 4 || FT->getReturnType() != FT->getParamType(0) ||
- !FT->getParamType(0)->isPointerTy() ||
- !FT->getParamType(1)->isPointerTy() ||
- FT->getParamType(2) != TD->getIntPtrType(Context) ||
- FT->getParamType(3) != TD->getIntPtrType(Context))
- return 0;
-
- if (isFoldable(3, 2, false)) {
- B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(1),
- CI->getArgOperand(2), 1);
- return CI->getArgOperand(0);
- }
- return 0;
- }
-};
-
-struct MemMoveChkOpt : public InstFortifiedLibCallOptimization {
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- this->CI = CI;
- FunctionType *FT = Callee->getFunctionType();
- LLVMContext &Context = CI->getParent()->getContext();
-
- // Check if this has the right signature.
- if (FT->getNumParams() != 4 || FT->getReturnType() != FT->getParamType(0) ||
- !FT->getParamType(0)->isPointerTy() ||
- !FT->getParamType(1)->isPointerTy() ||
- FT->getParamType(2) != TD->getIntPtrType(Context) ||
- FT->getParamType(3) != TD->getIntPtrType(Context))
- return 0;
-
- if (isFoldable(3, 2, false)) {
- B.CreateMemMove(CI->getArgOperand(0), CI->getArgOperand(1),
- CI->getArgOperand(2), 1);
- return CI->getArgOperand(0);
- }
- return 0;
- }
-};
-
-struct MemSetChkOpt : public InstFortifiedLibCallOptimization {
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- this->CI = CI;
- FunctionType *FT = Callee->getFunctionType();
- LLVMContext &Context = CI->getParent()->getContext();
-
- // Check if this has the right signature.
- if (FT->getNumParams() != 4 || FT->getReturnType() != FT->getParamType(0) ||
- !FT->getParamType(0)->isPointerTy() ||
- !FT->getParamType(1)->isIntegerTy() ||
- FT->getParamType(2) != TD->getIntPtrType(Context) ||
- FT->getParamType(3) != TD->getIntPtrType(Context))
- return 0;
-
- if (isFoldable(3, 2, false)) {
- Value *Val = B.CreateIntCast(CI->getArgOperand(1), B.getInt8Ty(),
- false);
- B.CreateMemSet(CI->getArgOperand(0), Val, CI->getArgOperand(2), 1);
- return CI->getArgOperand(0);
- }
- return 0;
- }
-};
-
-struct StrCpyChkOpt : public InstFortifiedLibCallOptimization {
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- this->CI = CI;
- StringRef Name = Callee->getName();
- FunctionType *FT = Callee->getFunctionType();
- LLVMContext &Context = CI->getParent()->getContext();
-
- // Check if this has the right signature.
- if (FT->getNumParams() != 3 ||
- FT->getReturnType() != FT->getParamType(0) ||
- FT->getParamType(0) != FT->getParamType(1) ||
- FT->getParamType(0) != Type::getInt8PtrTy(Context) ||
- FT->getParamType(2) != TD->getIntPtrType(Context))
- return 0;
-
- Value *Dst = CI->getArgOperand(0), *Src = CI->getArgOperand(1);
- if (Dst == Src) // __strcpy_chk(x,x) -> x
- return Src;
-
- // If a) we don't have any length information, or b) we know this will
- // fit then just lower to a plain strcpy. Otherwise we'll keep our
- // strcpy_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 (isFoldable(2, 1, true)) {
- Value *Ret = EmitStrCpy(Dst, Src, B, TD, TLI, Name.substr(2, 6));
- return Ret;
- } else {
- // Maybe we can stil fold __strcpy_chk to __memcpy_chk.
- uint64_t Len = GetStringLength(Src);
- if (Len == 0) return 0;
-
- // This optimization require DataLayout.
- if (!TD) return 0;
-
- Value *Ret =
- EmitMemCpyChk(Dst, Src,
- ConstantInt::get(TD->getIntPtrType(Context), Len),
- CI->getArgOperand(2), B, TD, TLI);
- return Ret;
- }
- return 0;
- }
-};
-
-struct StpCpyChkOpt : public InstFortifiedLibCallOptimization {
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- this->CI = CI;
- StringRef Name = Callee->getName();
- FunctionType *FT = Callee->getFunctionType();
- LLVMContext &Context = CI->getParent()->getContext();
-
- // Check if this has the right signature.
- if (FT->getNumParams() != 3 ||
- FT->getReturnType() != FT->getParamType(0) ||
- FT->getParamType(0) != FT->getParamType(1) ||
- FT->getParamType(0) != Type::getInt8PtrTy(Context) ||
- FT->getParamType(2) != TD->getIntPtrType(FT->getParamType(0)))
- return 0;
-
- Value *Dst = CI->getArgOperand(0), *Src = CI->getArgOperand(1);
- if (Dst == Src) { // stpcpy(x,x) -> x+strlen(x)
- Value *StrLen = EmitStrLen(Src, B, TD, TLI);
- return StrLen ? B.CreateInBoundsGEP(Dst, StrLen) : 0;
- }
+ return false;
+}
- // If a) we don't have any length information, or b) we know this will
- // fit then just lower to a plain stpcpy. Otherwise we'll keep our
- // stpcpy_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 (isFoldable(2, 1, true)) {
- Value *Ret = EmitStrCpy(Dst, Src, B, TD, TLI, Name.substr(2, 6));
- return Ret;
- } else {
- // Maybe we can stil fold __stpcpy_chk to __memcpy_chk.
- uint64_t Len = GetStringLength(Src);
- if (Len == 0) return 0;
-
- // This optimization require DataLayout.
- if (!TD) return 0;
-
- Type *PT = FT->getParamType(0);
- Value *LenV = ConstantInt::get(TD->getIntPtrType(PT), Len);
- Value *DstEnd = B.CreateGEP(Dst,
- ConstantInt::get(TD->getIntPtrType(PT),
- Len - 1));
- if (!EmitMemCpyChk(Dst, Src, LenV, CI->getArgOperand(2), B, TD, TLI))
- return 0;
- return DstEnd;
- }
- return 0;
- }
-};
-
-struct StrNCpyChkOpt : public InstFortifiedLibCallOptimization {
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- this->CI = CI;
- StringRef Name = Callee->getName();
- FunctionType *FT = Callee->getFunctionType();
- LLVMContext &Context = CI->getParent()->getContext();
-
- // Check if this has the right signature.
- if (FT->getNumParams() != 4 || FT->getReturnType() != FT->getParamType(0) ||
- FT->getParamType(0) != FT->getParamType(1) ||
- FT->getParamType(0) != Type::getInt8PtrTy(Context) ||
- !FT->getParamType(2)->isIntegerTy() ||
- FT->getParamType(3) != TD->getIntPtrType(Context))
- return 0;
-
- if (isFoldable(3, 2, false)) {
- Value *Ret = EmitStrNCpy(CI->getArgOperand(0), CI->getArgOperand(1),
- CI->getArgOperand(2), B, TD, TLI,
- Name.substr(2, 7));
- return Ret;
- }
- return 0;
+/// \brief Returns whether \p F matches the signature expected for the
+/// string/memory copying library function \p Func.
+/// Acceptable functions are st[rp][n]?cpy, memove, memcpy, and memset.
+/// Their fortified (_chk) counterparts are also accepted.
+static bool checkStringCopyLibFuncSignature(Function *F, LibFunc::Func Func) {
+ const DataLayout &DL = F->getParent()->getDataLayout();
+ FunctionType *FT = F->getFunctionType();
+ LLVMContext &Context = F->getContext();
+ Type *PCharTy = Type::getInt8PtrTy(Context);
+ Type *SizeTTy = DL.getIntPtrType(Context);
+ unsigned NumParams = FT->getNumParams();
+
+ // All string libfuncs return the same type as the first parameter.
+ if (FT->getReturnType() != FT->getParamType(0))
+ return false;
+
+ switch (Func) {
+ default:
+ llvm_unreachable("Can't check signature for non-string-copy libfunc.");
+ case LibFunc::stpncpy_chk:
+ case LibFunc::strncpy_chk:
+ --NumParams; // fallthrough
+ case LibFunc::stpncpy:
+ case LibFunc::strncpy: {
+ if (NumParams != 3 || FT->getParamType(0) != FT->getParamType(1) ||
+ FT->getParamType(0) != PCharTy || !FT->getParamType(2)->isIntegerTy())
+ return false;
+ break;
+ }
+ case LibFunc::strcpy_chk:
+ case LibFunc::stpcpy_chk:
+ --NumParams; // fallthrough
+ case LibFunc::stpcpy:
+ case LibFunc::strcpy: {
+ if (NumParams != 2 || FT->getParamType(0) != FT->getParamType(1) ||
+ FT->getParamType(0) != PCharTy)
+ return false;
+ break;
+ }
+ case LibFunc::memmove_chk:
+ case LibFunc::memcpy_chk:
+ --NumParams; // fallthrough
+ case LibFunc::memmove:
+ case LibFunc::memcpy: {
+ if (NumParams != 3 || !FT->getParamType(0)->isPointerTy() ||
+ !FT->getParamType(1)->isPointerTy() || FT->getParamType(2) != SizeTTy)
+ return false;
+ break;
+ }
+ case LibFunc::memset_chk:
+ --NumParams; // fallthrough
+ case LibFunc::memset: {
+ if (NumParams != 3 || !FT->getParamType(0)->isPointerTy() ||
+ !FT->getParamType(1)->isIntegerTy() || FT->getParamType(2) != SizeTTy)
+ return false;
+ break;
}
-};
+ }
+ // If this is a fortified libcall, the last parameter is a size_t.
+ if (NumParams == FT->getNumParams() - 1)
+ return FT->getParamType(FT->getNumParams() - 1) == SizeTTy;
+ return true;
+}
//===----------------------------------------------------------------------===//
// String and Memory Library Call Optimizations
//===----------------------------------------------------------------------===//
-struct StrCatOpt : public LibCallOptimization {
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- // Verify the "strcat" function prototype.
- FunctionType *FT = Callee->getFunctionType();
- if (FT->getNumParams() != 2 ||
- FT->getReturnType() != B.getInt8PtrTy() ||
- FT->getParamType(0) != FT->getReturnType() ||
- FT->getParamType(1) != FT->getReturnType())
- return 0;
-
- // Extract some information from the instruction
- Value *Dst = CI->getArgOperand(0);
- Value *Src = CI->getArgOperand(1);
-
- // See if we can get the length of the input string.
- uint64_t Len = GetStringLength(Src);
- if (Len == 0) return 0;
- --Len; // Unbias length.
-
- // Handle the simple, do-nothing case: strcat(x, "") -> x
- if (Len == 0)
- return Dst;
-
- // These optimizations require DataLayout.
- if (!TD) return 0;
-
- return emitStrLenMemCpy(Src, Dst, Len, B);
- }
-
- Value *emitStrLenMemCpy(Value *Src, Value *Dst, uint64_t Len,
- IRBuilder<> &B) {
- // We need to find the end of the destination string. That's where the
- // memory is to be moved to. We just generate a call to strlen.
- Value *DstLen = EmitStrLen(Dst, B, TD, TLI);
- if (!DstLen)
- return 0;
-
- // Now that we have the destination's length, we must index into the
- // destination's pointer to get the actual memcpy destination (end of
- // the string .. we're concatenating).
- Value *CpyDst = B.CreateGEP(Dst, DstLen, "endptr");
-
- // We have enough information to now generate the memcpy call to do the
- // concatenation for us. Make a memcpy to copy the nul byte with align = 1.
- B.CreateMemCpy(CpyDst, Src,
- ConstantInt::get(TD->getIntPtrType(*Context), Len + 1), 1);
+Value *LibCallSimplifier::optimizeStrCat(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
+ // Verify the "strcat" function prototype.
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 2||
+ FT->getReturnType() != B.getInt8PtrTy() ||
+ FT->getParamType(0) != FT->getReturnType() ||
+ FT->getParamType(1) != FT->getReturnType())
+ return nullptr;
+
+ // Extract some information from the instruction
+ Value *Dst = CI->getArgOperand(0);
+ Value *Src = CI->getArgOperand(1);
+
+ // See if we can get the length of the input string.
+ uint64_t Len = GetStringLength(Src);
+ if (Len == 0)
+ return nullptr;
+ --Len; // Unbias length.
+
+ // Handle the simple, do-nothing case: strcat(x, "") -> x
+ if (Len == 0)
return Dst;
- }
-};
-
-struct StrNCatOpt : public StrCatOpt {
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- // Verify the "strncat" function prototype.
- FunctionType *FT = Callee->getFunctionType();
- if (FT->getNumParams() != 3 ||
- FT->getReturnType() != B.getInt8PtrTy() ||
- FT->getParamType(0) != FT->getReturnType() ||
- FT->getParamType(1) != FT->getReturnType() ||
- !FT->getParamType(2)->isIntegerTy())
- return 0;
-
- // Extract some information from the instruction
- Value *Dst = CI->getArgOperand(0);
- Value *Src = CI->getArgOperand(1);
- uint64_t Len;
-
- // We don't do anything if length is not constant
- if (ConstantInt *LengthArg = dyn_cast<ConstantInt>(CI->getArgOperand(2)))
- Len = LengthArg->getZExtValue();
- else
- return 0;
-
- // See if we can get the length of the input string.
- uint64_t SrcLen = GetStringLength(Src);
- if (SrcLen == 0) return 0;
- --SrcLen; // Unbias length.
-
- // Handle the simple, do-nothing cases:
- // strncat(x, "", c) -> x
- // strncat(x, c, 0) -> x
- if (SrcLen == 0 || Len == 0) return Dst;
-
- // These optimizations require DataLayout.
- if (!TD) return 0;
-
- // We don't optimize this case
- if (Len < SrcLen) return 0;
-
- // strncat(x, s, c) -> strcat(x, s)
- // s is constant so the strcat can be optimized further
- return emitStrLenMemCpy(Src, Dst, SrcLen, B);
- }
-};
-
-struct StrChrOpt : public LibCallOptimization {
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- // Verify the "strchr" function prototype.
- FunctionType *FT = Callee->getFunctionType();
- if (FT->getNumParams() != 2 ||
- FT->getReturnType() != B.getInt8PtrTy() ||
- FT->getParamType(0) != FT->getReturnType() ||
- !FT->getParamType(1)->isIntegerTy(32))
- return 0;
-
- Value *SrcStr = CI->getArgOperand(0);
-
- // If the second operand is non-constant, see if we can compute the length
- // of the input string and turn this into memchr.
- ConstantInt *CharC = dyn_cast<ConstantInt>(CI->getArgOperand(1));
- if (CharC == 0) {
- // These optimizations require DataLayout.
- if (!TD) return 0;
-
- uint64_t Len = GetStringLength(SrcStr);
- if (Len == 0 || !FT->getParamType(1)->isIntegerTy(32))// memchr needs i32.
- return 0;
-
- return EmitMemChr(SrcStr, CI->getArgOperand(1), // include nul.
- ConstantInt::get(TD->getIntPtrType(*Context), Len),
- B, TD, TLI);
- }
- // Otherwise, the character is a constant, see if the first argument is
- // a string literal. If so, we can constant fold.
- StringRef Str;
- if (!getConstantStringInfo(SrcStr, Str))
- return 0;
-
- // Compute the offset, make sure to handle the case when we're searching for
- // zero (a weird way to spell strlen).
- size_t I = CharC->getSExtValue() == 0 ?
- Str.size() : Str.find(CharC->getSExtValue());
- if (I == StringRef::npos) // Didn't find the char. strchr returns null.
- return Constant::getNullValue(CI->getType());
+ return emitStrLenMemCpy(Src, Dst, Len, B);
+}
- // strchr(s+n,c) -> gep(s+n+i,c)
- return B.CreateGEP(SrcStr, B.getInt64(I), "strchr");
- }
-};
-
-struct StrRChrOpt : public LibCallOptimization {
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- // Verify the "strrchr" function prototype.
- FunctionType *FT = Callee->getFunctionType();
- if (FT->getNumParams() != 2 ||
- FT->getReturnType() != B.getInt8PtrTy() ||
- FT->getParamType(0) != FT->getReturnType() ||
- !FT->getParamType(1)->isIntegerTy(32))
- return 0;
-
- Value *SrcStr = CI->getArgOperand(0);
- ConstantInt *CharC = dyn_cast<ConstantInt>(CI->getArgOperand(1));
-
- // Cannot fold anything if we're not looking for a constant.
- if (!CharC)
- return 0;
-
- StringRef Str;
- if (!getConstantStringInfo(SrcStr, Str)) {
- // strrchr(s, 0) -> strchr(s, 0)
- if (TD && CharC->isZero())
- return EmitStrChr(SrcStr, '\0', B, TD, TLI);
- return 0;
- }
+Value *LibCallSimplifier::emitStrLenMemCpy(Value *Src, Value *Dst, uint64_t Len,
+ IRBuilder<> &B) {
+ // We need to find the end of the destination string. That's where the
+ // memory is to be moved to. We just generate a call to strlen.
+ Value *DstLen = EmitStrLen(Dst, B, DL, TLI);
+ if (!DstLen)
+ return nullptr;
+
+ // Now that we have the destination's length, we must index into the
+ // destination's pointer to get the actual memcpy destination (end of
+ // the string .. we're concatenating).
+ Value *CpyDst = B.CreateGEP(B.getInt8Ty(), Dst, DstLen, "endptr");
+
+ // We have enough information to now generate the memcpy call to do the
+ // concatenation for us. Make a memcpy to copy the nul byte with align = 1.
+ B.CreateMemCpy(CpyDst, Src,
+ ConstantInt::get(DL.getIntPtrType(Src->getContext()), Len + 1),
+ 1);
+ return Dst;
+}
- // Compute the offset.
- size_t I = CharC->getSExtValue() == 0 ?
- Str.size() : Str.rfind(CharC->getSExtValue());
- if (I == StringRef::npos) // Didn't find the char. Return null.
- return Constant::getNullValue(CI->getType());
+Value *LibCallSimplifier::optimizeStrNCat(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
+ // Verify the "strncat" function prototype.
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 3 || FT->getReturnType() != B.getInt8PtrTy() ||
+ FT->getParamType(0) != FT->getReturnType() ||
+ FT->getParamType(1) != FT->getReturnType() ||
+ !FT->getParamType(2)->isIntegerTy())
+ return nullptr;
+
+ // Extract some information from the instruction
+ Value *Dst = CI->getArgOperand(0);
+ Value *Src = CI->getArgOperand(1);
+ uint64_t Len;
+
+ // We don't do anything if length is not constant
+ if (ConstantInt *LengthArg = dyn_cast<ConstantInt>(CI->getArgOperand(2)))
+ Len = LengthArg->getZExtValue();
+ else
+ return nullptr;
+
+ // See if we can get the length of the input string.
+ uint64_t SrcLen = GetStringLength(Src);
+ if (SrcLen == 0)
+ return nullptr;
+ --SrcLen; // Unbias length.
+
+ // Handle the simple, do-nothing cases:
+ // strncat(x, "", c) -> x
+ // strncat(x, c, 0) -> x
+ if (SrcLen == 0 || Len == 0)
+ return Dst;
- // strrchr(s+n,c) -> gep(s+n+i,c)
- return B.CreateGEP(SrcStr, B.getInt64(I), "strrchr");
- }
-};
-
-struct StrCmpOpt : public LibCallOptimization {
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- // Verify the "strcmp" function prototype.
- FunctionType *FT = Callee->getFunctionType();
- if (FT->getNumParams() != 2 ||
- !FT->getReturnType()->isIntegerTy(32) ||
- FT->getParamType(0) != FT->getParamType(1) ||
- FT->getParamType(0) != B.getInt8PtrTy())
- return 0;
-
- Value *Str1P = CI->getArgOperand(0), *Str2P = CI->getArgOperand(1);
- if (Str1P == Str2P) // strcmp(x,x) -> 0
- return ConstantInt::get(CI->getType(), 0);
-
- StringRef Str1, Str2;
- bool HasStr1 = getConstantStringInfo(Str1P, Str1);
- bool HasStr2 = getConstantStringInfo(Str2P, Str2);
-
- // strcmp(x, y) -> cnst (if both x and y are constant strings)
- if (HasStr1 && HasStr2)
- return ConstantInt::get(CI->getType(), Str1.compare(Str2));
-
- if (HasStr1 && Str1.empty()) // strcmp("", x) -> -*x
- return B.CreateNeg(B.CreateZExt(B.CreateLoad(Str2P, "strcmpload"),
- CI->getType()));
-
- if (HasStr2 && Str2.empty()) // strcmp(x,"") -> *x
- return B.CreateZExt(B.CreateLoad(Str1P, "strcmpload"), CI->getType());
-
- // strcmp(P, "x") -> memcmp(P, "x", 2)
- uint64_t Len1 = GetStringLength(Str1P);
- uint64_t Len2 = GetStringLength(Str2P);
- if (Len1 && Len2) {
- // These optimizations require DataLayout.
- if (!TD) return 0;
-
- return EmitMemCmp(Str1P, Str2P,
- ConstantInt::get(TD->getIntPtrType(*Context),
- std::min(Len1, Len2)), B, TD, TLI);
- }
+ // We don't optimize this case
+ if (Len < SrcLen)
+ return nullptr;
- return 0;
- }
-};
-
-struct StrNCmpOpt : public LibCallOptimization {
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- // Verify the "strncmp" function prototype.
- FunctionType *FT = Callee->getFunctionType();
- if (FT->getNumParams() != 3 ||
- !FT->getReturnType()->isIntegerTy(32) ||
- FT->getParamType(0) != FT->getParamType(1) ||
- FT->getParamType(0) != B.getInt8PtrTy() ||
- !FT->getParamType(2)->isIntegerTy())
- return 0;
-
- Value *Str1P = CI->getArgOperand(0), *Str2P = CI->getArgOperand(1);
- if (Str1P == Str2P) // strncmp(x,x,n) -> 0
- return ConstantInt::get(CI->getType(), 0);
-
- // Get the length argument if it is constant.
- uint64_t Length;
- if (ConstantInt *LengthArg = dyn_cast<ConstantInt>(CI->getArgOperand(2)))
- Length = LengthArg->getZExtValue();
- else
- return 0;
-
- if (Length == 0) // strncmp(x,y,0) -> 0
- return ConstantInt::get(CI->getType(), 0);
-
- if (TD && Length == 1) // strncmp(x,y,1) -> memcmp(x,y,1)
- return EmitMemCmp(Str1P, Str2P, CI->getArgOperand(2), B, TD, TLI);
-
- StringRef Str1, Str2;
- bool HasStr1 = getConstantStringInfo(Str1P, Str1);
- bool HasStr2 = getConstantStringInfo(Str2P, Str2);
-
- // strncmp(x, y) -> cnst (if both x and y are constant strings)
- if (HasStr1 && HasStr2) {
- StringRef SubStr1 = Str1.substr(0, Length);
- StringRef SubStr2 = Str2.substr(0, Length);
- return ConstantInt::get(CI->getType(), SubStr1.compare(SubStr2));
- }
+ // strncat(x, s, c) -> strcat(x, s)
+ // s is constant so the strcat can be optimized further
+ return emitStrLenMemCpy(Src, Dst, SrcLen, B);
+}
+
+Value *LibCallSimplifier::optimizeStrChr(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
+ // Verify the "strchr" function prototype.
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 2 || FT->getReturnType() != B.getInt8PtrTy() ||
+ FT->getParamType(0) != FT->getReturnType() ||
+ !FT->getParamType(1)->isIntegerTy(32))
+ return nullptr;
+
+ Value *SrcStr = CI->getArgOperand(0);
+
+ // If the second operand is non-constant, see if we can compute the length
+ // of the input string and turn this into memchr.
+ ConstantInt *CharC = dyn_cast<ConstantInt>(CI->getArgOperand(1));
+ if (!CharC) {
+ uint64_t Len = GetStringLength(SrcStr);
+ if (Len == 0 || !FT->getParamType(1)->isIntegerTy(32)) // memchr needs i32.
+ return nullptr;
+
+ return EmitMemChr(SrcStr, CI->getArgOperand(1), // include nul.
+ ConstantInt::get(DL.getIntPtrType(CI->getContext()), Len),
+ B, DL, TLI);
+ }
- if (HasStr1 && Str1.empty()) // strncmp("", x, n) -> -*x
- return B.CreateNeg(B.CreateZExt(B.CreateLoad(Str2P, "strcmpload"),
- CI->getType()));
+ // Otherwise, the character is a constant, see if the first argument is
+ // a string literal. If so, we can constant fold.
+ StringRef Str;
+ if (!getConstantStringInfo(SrcStr, Str)) {
+ if (CharC->isZero()) // strchr(p, 0) -> p + strlen(p)
+ return B.CreateGEP(B.getInt8Ty(), SrcStr, EmitStrLen(SrcStr, B, DL, TLI), "strchr");
+ return nullptr;
+ }
- if (HasStr2 && Str2.empty()) // strncmp(x, "", n) -> *x
- return B.CreateZExt(B.CreateLoad(Str1P, "strcmpload"), CI->getType());
+ // Compute the offset, make sure to handle the case when we're searching for
+ // zero (a weird way to spell strlen).
+ size_t I = (0xFF & CharC->getSExtValue()) == 0
+ ? Str.size()
+ : Str.find(CharC->getSExtValue());
+ if (I == StringRef::npos) // Didn't find the char. strchr returns null.
+ return Constant::getNullValue(CI->getType());
- return 0;
+ // strchr(s+n,c) -> gep(s+n+i,c)
+ return B.CreateGEP(B.getInt8Ty(), SrcStr, B.getInt64(I), "strchr");
+}
+
+Value *LibCallSimplifier::optimizeStrRChr(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
+ // Verify the "strrchr" function prototype.
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 2 || FT->getReturnType() != B.getInt8PtrTy() ||
+ FT->getParamType(0) != FT->getReturnType() ||
+ !FT->getParamType(1)->isIntegerTy(32))
+ return nullptr;
+
+ Value *SrcStr = CI->getArgOperand(0);
+ ConstantInt *CharC = dyn_cast<ConstantInt>(CI->getArgOperand(1));
+
+ // Cannot fold anything if we're not looking for a constant.
+ if (!CharC)
+ return nullptr;
+
+ StringRef Str;
+ if (!getConstantStringInfo(SrcStr, Str)) {
+ // strrchr(s, 0) -> strchr(s, 0)
+ if (CharC->isZero())
+ return EmitStrChr(SrcStr, '\0', B, TLI);
+ return nullptr;
}
-};
-struct StrCpyOpt : public LibCallOptimization {
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- // Verify the "strcpy" function prototype.
- FunctionType *FT = Callee->getFunctionType();
- if (FT->getNumParams() != 2 ||
- FT->getReturnType() != FT->getParamType(0) ||
- FT->getParamType(0) != FT->getParamType(1) ||
- FT->getParamType(0) != B.getInt8PtrTy())
- return 0;
+ // Compute the offset.
+ size_t I = (0xFF & CharC->getSExtValue()) == 0
+ ? Str.size()
+ : Str.rfind(CharC->getSExtValue());
+ if (I == StringRef::npos) // Didn't find the char. Return null.
+ return Constant::getNullValue(CI->getType());
- Value *Dst = CI->getArgOperand(0), *Src = CI->getArgOperand(1);
- if (Dst == Src) // strcpy(x,x) -> x
- return Src;
+ // strrchr(s+n,c) -> gep(s+n+i,c)
+ return B.CreateGEP(B.getInt8Ty(), SrcStr, B.getInt64(I), "strrchr");
+}
- // These optimizations require DataLayout.
- if (!TD) return 0;
+Value *LibCallSimplifier::optimizeStrCmp(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
+ // Verify the "strcmp" function prototype.
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 2 || !FT->getReturnType()->isIntegerTy(32) ||
+ FT->getParamType(0) != FT->getParamType(1) ||
+ FT->getParamType(0) != B.getInt8PtrTy())
+ return nullptr;
+
+ Value *Str1P = CI->getArgOperand(0), *Str2P = CI->getArgOperand(1);
+ if (Str1P == Str2P) // strcmp(x,x) -> 0
+ return ConstantInt::get(CI->getType(), 0);
+
+ StringRef Str1, Str2;
+ bool HasStr1 = getConstantStringInfo(Str1P, Str1);
+ bool HasStr2 = getConstantStringInfo(Str2P, Str2);
+
+ // strcmp(x, y) -> cnst (if both x and y are constant strings)
+ if (HasStr1 && HasStr2)
+ return ConstantInt::get(CI->getType(), Str1.compare(Str2));
+
+ if (HasStr1 && Str1.empty()) // strcmp("", x) -> -*x
+ return B.CreateNeg(
+ B.CreateZExt(B.CreateLoad(Str2P, "strcmpload"), CI->getType()));
+
+ if (HasStr2 && Str2.empty()) // strcmp(x,"") -> *x
+ return B.CreateZExt(B.CreateLoad(Str1P, "strcmpload"), CI->getType());
+
+ // strcmp(P, "x") -> memcmp(P, "x", 2)
+ uint64_t Len1 = GetStringLength(Str1P);
+ uint64_t Len2 = GetStringLength(Str2P);
+ if (Len1 && Len2) {
+ return EmitMemCmp(Str1P, Str2P,
+ ConstantInt::get(DL.getIntPtrType(CI->getContext()),
+ std::min(Len1, Len2)),
+ B, DL, TLI);
+ }
- // See if we can get the length of the input string.
- uint64_t Len = GetStringLength(Src);
- if (Len == 0) return 0;
+ 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.
- B.CreateMemCpy(Dst, Src,
- ConstantInt::get(TD->getIntPtrType(*Context), Len), 1);
- return Dst;
+Value *LibCallSimplifier::optimizeStrNCmp(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
+ // Verify the "strncmp" function prototype.
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 3 || !FT->getReturnType()->isIntegerTy(32) ||
+ FT->getParamType(0) != FT->getParamType(1) ||
+ FT->getParamType(0) != B.getInt8PtrTy() ||
+ !FT->getParamType(2)->isIntegerTy())
+ return nullptr;
+
+ Value *Str1P = CI->getArgOperand(0), *Str2P = CI->getArgOperand(1);
+ if (Str1P == Str2P) // strncmp(x,x,n) -> 0
+ return ConstantInt::get(CI->getType(), 0);
+
+ // Get the length argument if it is constant.
+ uint64_t Length;
+ if (ConstantInt *LengthArg = dyn_cast<ConstantInt>(CI->getArgOperand(2)))
+ Length = LengthArg->getZExtValue();
+ else
+ return nullptr;
+
+ if (Length == 0) // strncmp(x,y,0) -> 0
+ return ConstantInt::get(CI->getType(), 0);
+
+ if (Length == 1) // strncmp(x,y,1) -> memcmp(x,y,1)
+ return EmitMemCmp(Str1P, Str2P, CI->getArgOperand(2), B, DL, TLI);
+
+ StringRef Str1, Str2;
+ bool HasStr1 = getConstantStringInfo(Str1P, Str1);
+ bool HasStr2 = getConstantStringInfo(Str2P, Str2);
+
+ // strncmp(x, y) -> cnst (if both x and y are constant strings)
+ if (HasStr1 && HasStr2) {
+ StringRef SubStr1 = Str1.substr(0, Length);
+ StringRef SubStr2 = Str2.substr(0, Length);
+ return ConstantInt::get(CI->getType(), SubStr1.compare(SubStr2));
}
-};
-
-struct StpCpyOpt: public LibCallOptimization {
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- // Verify the "stpcpy" function prototype.
- FunctionType *FT = Callee->getFunctionType();
- if (FT->getNumParams() != 2 ||
- FT->getReturnType() != FT->getParamType(0) ||
- FT->getParamType(0) != FT->getParamType(1) ||
- FT->getParamType(0) != B.getInt8PtrTy())
- return 0;
-
- // These optimizations require DataLayout.
- if (!TD) return 0;
-
- Value *Dst = CI->getArgOperand(0), *Src = CI->getArgOperand(1);
- if (Dst == Src) { // stpcpy(x,x) -> x+strlen(x)
- Value *StrLen = EmitStrLen(Src, B, TD, TLI);
- return StrLen ? B.CreateInBoundsGEP(Dst, StrLen) : 0;
- }
- // See if we can get the length of the input string.
- uint64_t Len = GetStringLength(Src);
- if (Len == 0) return 0;
-
- Type *PT = FT->getParamType(0);
- Value *LenV = ConstantInt::get(TD->getIntPtrType(PT), Len);
- Value *DstEnd = B.CreateGEP(Dst,
- ConstantInt::get(TD->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.
- B.CreateMemCpy(Dst, Src, LenV, 1);
- return DstEnd;
- }
-};
-
-struct StrNCpyOpt : public LibCallOptimization {
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- FunctionType *FT = Callee->getFunctionType();
- if (FT->getNumParams() != 3 || FT->getReturnType() != FT->getParamType(0) ||
- FT->getParamType(0) != FT->getParamType(1) ||
- FT->getParamType(0) != B.getInt8PtrTy() ||
- !FT->getParamType(2)->isIntegerTy())
- return 0;
-
- Value *Dst = CI->getArgOperand(0);
- Value *Src = CI->getArgOperand(1);
- Value *LenOp = CI->getArgOperand(2);
-
- // See if we can get the length of the input string.
- uint64_t SrcLen = GetStringLength(Src);
- if (SrcLen == 0) return 0;
- --SrcLen;
-
- if (SrcLen == 0) {
- // strncpy(x, "", y) -> memset(x, '\0', y, 1)
- B.CreateMemSet(Dst, B.getInt8('\0'), LenOp, 1);
- return Dst;
- }
+ if (HasStr1 && Str1.empty()) // strncmp("", x, n) -> -*x
+ return B.CreateNeg(
+ B.CreateZExt(B.CreateLoad(Str2P, "strcmpload"), CI->getType()));
- uint64_t Len;
- if (ConstantInt *LengthArg = dyn_cast<ConstantInt>(LenOp))
- Len = LengthArg->getZExtValue();
- else
- return 0;
+ if (HasStr2 && Str2.empty()) // strncmp(x, "", n) -> *x
+ return B.CreateZExt(B.CreateLoad(Str1P, "strcmpload"), CI->getType());
- if (Len == 0) return Dst; // strncpy(x, y, 0) -> x
+ return nullptr;
+}
- // These optimizations require DataLayout.
- if (!TD) return 0;
+Value *LibCallSimplifier::optimizeStrCpy(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
- // Let strncpy handle the zero padding
- if (Len > SrcLen+1) return 0;
+ if (!checkStringCopyLibFuncSignature(Callee, LibFunc::strcpy))
+ return nullptr;
- Type *PT = FT->getParamType(0);
- // strncpy(x, s, c) -> memcpy(x, s, c, 1) [s and c are constant]
- B.CreateMemCpy(Dst, Src,
- ConstantInt::get(TD->getIntPtrType(PT), Len), 1);
+ Value *Dst = CI->getArgOperand(0), *Src = CI->getArgOperand(1);
+ if (Dst == Src) // strcpy(x,x) -> x
+ return Src;
- return Dst;
+ // See if we can get the length of the input string.
+ uint64_t Len = GetStringLength(Src);
+ if (Len == 0)
+ 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.
+ B.CreateMemCpy(Dst, Src,
+ ConstantInt::get(DL.getIntPtrType(CI->getContext()), Len), 1);
+ return Dst;
+}
+
+Value *LibCallSimplifier::optimizeStpCpy(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
+ if (!checkStringCopyLibFuncSignature(Callee, LibFunc::stpcpy))
+ return nullptr;
+
+ 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;
}
-};
-
-struct StrLenOpt : public LibCallOptimization {
- virtual bool ignoreCallingConv() { return true; }
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- FunctionType *FT = Callee->getFunctionType();
- if (FT->getNumParams() != 1 ||
- FT->getParamType(0) != B.getInt8PtrTy() ||
- !FT->getReturnType()->isIntegerTy())
- return 0;
-
- Value *Src = CI->getArgOperand(0);
-
- // Constant folding: strlen("xyz") -> 3
- if (uint64_t Len = GetStringLength(Src))
- return ConstantInt::get(CI->getType(), Len-1);
-
- // strlen(x) != 0 --> *x != 0
- // strlen(x) == 0 --> *x == 0
- if (isOnlyUsedInZeroEqualityComparison(CI))
- return B.CreateZExt(B.CreateLoad(Src, "strlenfirst"), CI->getType());
- return 0;
- }
-};
-
-struct StrPBrkOpt : public LibCallOptimization {
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- FunctionType *FT = Callee->getFunctionType();
- if (FT->getNumParams() != 2 ||
- FT->getParamType(0) != B.getInt8PtrTy() ||
- FT->getParamType(1) != FT->getParamType(0) ||
- FT->getReturnType() != FT->getParamType(0))
- return 0;
-
- StringRef S1, S2;
- bool HasS1 = getConstantStringInfo(CI->getArgOperand(0), S1);
- bool HasS2 = getConstantStringInfo(CI->getArgOperand(1), S2);
-
- // strpbrk(s, "") -> NULL
- // strpbrk("", s) -> NULL
- 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 == std::string::npos) // No match.
- return Constant::getNullValue(CI->getType());
+ // See if we can get the length of the input string.
+ uint64_t Len = GetStringLength(Src);
+ if (Len == 0)
+ return nullptr;
- return B.CreateGEP(CI->getArgOperand(0), B.getInt64(I), "strpbrk");
- }
+ 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));
- // strpbrk(s, "a") -> strchr(s, 'a')
- if (TD && HasS2 && S2.size() == 1)
- return EmitStrChr(CI->getArgOperand(0), S2[0], B, TD, TLI);
+ // 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.
+ B.CreateMemCpy(Dst, Src, LenV, 1);
+ return DstEnd;
+}
- return 0;
+Value *LibCallSimplifier::optimizeStrNCpy(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
+ if (!checkStringCopyLibFuncSignature(Callee, LibFunc::strncpy))
+ return nullptr;
+
+ Value *Dst = CI->getArgOperand(0);
+ Value *Src = CI->getArgOperand(1);
+ Value *LenOp = CI->getArgOperand(2);
+
+ // See if we can get the length of the input string.
+ uint64_t SrcLen = GetStringLength(Src);
+ if (SrcLen == 0)
+ return nullptr;
+ --SrcLen;
+
+ if (SrcLen == 0) {
+ // strncpy(x, "", y) -> memset(x, '\0', y, 1)
+ B.CreateMemSet(Dst, B.getInt8('\0'), LenOp, 1);
+ return Dst;
}
-};
-struct StrToOpt : public LibCallOptimization {
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- FunctionType *FT = Callee->getFunctionType();
- if ((FT->getNumParams() != 2 && FT->getNumParams() != 3) ||
- !FT->getParamType(0)->isPointerTy() ||
- !FT->getParamType(1)->isPointerTy())
- return 0;
+ uint64_t Len;
+ if (ConstantInt *LengthArg = dyn_cast<ConstantInt>(LenOp))
+ Len = LengthArg->getZExtValue();
+ else
+ return nullptr;
- 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->addAttribute(1, Attribute::NoCapture);
- }
+ if (Len == 0)
+ return Dst; // strncpy(x, y, 0) -> x
+
+ // Let strncpy handle the zero padding
+ if (Len > SrcLen + 1)
+ return nullptr;
+
+ Type *PT = Callee->getFunctionType()->getParamType(0);
+ // strncpy(x, s, c) -> memcpy(x, s, c, 1) [s and c are constant]
+ B.CreateMemCpy(Dst, Src, ConstantInt::get(DL.getIntPtrType(PT), Len), 1);
- return 0;
+ return Dst;
+}
+
+Value *LibCallSimplifier::optimizeStrLen(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 1 || FT->getParamType(0) != B.getInt8PtrTy() ||
+ !FT->getReturnType()->isIntegerTy())
+ return nullptr;
+
+ Value *Src = CI->getArgOperand(0);
+
+ // Constant folding: strlen("xyz") -> 3
+ if (uint64_t Len = GetStringLength(Src))
+ return ConstantInt::get(CI->getType(), Len - 1);
+
+ // strlen(x?"foo":"bars") --> x ? 3 : 4
+ if (SelectInst *SI = dyn_cast<SelectInst>(Src)) {
+ uint64_t LenTrue = GetStringLength(SI->getTrueValue());
+ uint64_t LenFalse = GetStringLength(SI->getFalseValue());
+ if (LenTrue && LenFalse) {
+ Function *Caller = CI->getParent()->getParent();
+ emitOptimizationRemark(CI->getContext(), "simplify-libcalls", *Caller,
+ SI->getDebugLoc(),
+ "folded strlen(select) to select of constants");
+ return B.CreateSelect(SI->getCondition(),
+ ConstantInt::get(CI->getType(), LenTrue - 1),
+ ConstantInt::get(CI->getType(), LenFalse - 1));
+ }
}
-};
-struct StrSpnOpt : public LibCallOptimization {
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- FunctionType *FT = Callee->getFunctionType();
- if (FT->getNumParams() != 2 ||
- FT->getParamType(0) != B.getInt8PtrTy() ||
- FT->getParamType(1) != FT->getParamType(0) ||
- !FT->getReturnType()->isIntegerTy())
- return 0;
+ // strlen(x) != 0 --> *x != 0
+ // strlen(x) == 0 --> *x == 0
+ if (isOnlyUsedInZeroEqualityComparison(CI))
+ return B.CreateZExt(B.CreateLoad(Src, "strlenfirst"), CI->getType());
- StringRef S1, S2;
- bool HasS1 = getConstantStringInfo(CI->getArgOperand(0), S1);
- bool HasS2 = getConstantStringInfo(CI->getArgOperand(1), S2);
+ return nullptr;
+}
- // strspn(s, "") -> 0
- // strspn("", s) -> 0
- if ((HasS1 && S1.empty()) || (HasS2 && S2.empty()))
+Value *LibCallSimplifier::optimizeStrPBrk(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 2 || FT->getParamType(0) != B.getInt8PtrTy() ||
+ FT->getParamType(1) != FT->getParamType(0) ||
+ FT->getReturnType() != FT->getParamType(0))
+ return nullptr;
+
+ 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());
- // 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 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, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
+ FunctionType *FT = Callee->getFunctionType();
+ if ((FT->getNumParams() != 2 && FT->getNumParams() != 3) ||
+ !FT->getParamType(0)->isPointerTy() ||
+ !FT->getParamType(1)->isPointerTy())
+ return nullptr;
+
+ 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->addAttribute(1, Attribute::NoCapture);
+ }
+
+ return nullptr;
+}
- return 0;
+Value *LibCallSimplifier::optimizeStrSpn(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 2 || FT->getParamType(0) != B.getInt8PtrTy() ||
+ FT->getParamType(1) != FT->getParamType(0) ||
+ !FT->getReturnType()->isIntegerTy())
+ return nullptr;
+
+ 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);
}
-};
-struct StrCSpnOpt : public LibCallOptimization {
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- FunctionType *FT = Callee->getFunctionType();
- if (FT->getNumParams() != 2 ||
- FT->getParamType(0) != B.getInt8PtrTy() ||
- FT->getParamType(1) != FT->getParamType(0) ||
- !FT->getReturnType()->isIntegerTy())
- return 0;
+ return nullptr;
+}
- StringRef S1, S2;
- bool HasS1 = getConstantStringInfo(CI->getArgOperand(0), S1);
- bool HasS2 = getConstantStringInfo(CI->getArgOperand(1), S2);
+Value *LibCallSimplifier::optimizeStrCSpn(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 2 || FT->getParamType(0) != B.getInt8PtrTy() ||
+ FT->getParamType(1) != FT->getParamType(0) ||
+ !FT->getReturnType()->isIntegerTy())
+ return nullptr;
+
+ 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) -> 0
- if (HasS1 && S1.empty())
- return Constant::getNullValue(CI->getType());
+ // strcspn(s, "") -> strlen(s)
+ if (HasS2 && S2.empty())
+ return EmitStrLen(CI->getArgOperand(0), B, DL, TLI);
- // 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);
- }
+ return nullptr;
+}
- // strcspn(s, "") -> strlen(s)
- if (TD && HasS2 && S2.empty())
- return EmitStrLen(CI->getArgOperand(0), B, TD, TLI);
-
- return 0;
- }
-};
-
-struct StrStrOpt : public LibCallOptimization {
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- FunctionType *FT = Callee->getFunctionType();
- if (FT->getNumParams() != 2 ||
- !FT->getParamType(0)->isPointerTy() ||
- !FT->getParamType(1)->isPointerTy() ||
- !FT->getReturnType()->isPointerTy())
- return 0;
-
- // 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 (TD && isOnlyUsedInEqualityComparison(CI, CI->getArgOperand(0))) {
- Value *StrLen = EmitStrLen(CI->getArgOperand(1), B, TD, TLI);
- if (!StrLen)
- return 0;
- Value *StrNCmp = EmitStrNCmp(CI->getArgOperand(0), CI->getArgOperand(1),
- StrLen, B, TD, TLI);
- if (!StrNCmp)
- return 0;
- for (Value::use_iterator UI = CI->use_begin(), UE = CI->use_end();
- UI != UE; ) {
- ICmpInst *Old = cast<ICmpInst>(*UI++);
- Value *Cmp = B.CreateICmp(Old->getPredicate(), StrNCmp,
- ConstantInt::getNullValue(StrNCmp->getType()),
- "cmp");
- LCS->replaceAllUsesWith(Old, Cmp);
- }
- return CI;
+Value *LibCallSimplifier::optimizeStrStr(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 2 || !FT->getParamType(0)->isPointerTy() ||
+ !FT->getParamType(1)->isPointerTy() ||
+ !FT->getReturnType()->isPointerTy())
+ return nullptr;
+
+ // 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);
+ // 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());
+ // 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) {
- std::string::size_type Offset = SearchStr.find(ToFindStr);
+ // 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());
+ 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(Result, Offset, "strstr");
- return B.CreateBitCast(Result, CI->getType());
- }
+ // strstr("abcd", "bc") -> gep((char*)"abcd", 1)
+ Value *Result = CastToCStr(CI->getArgOperand(0), B);
+ Result = B.CreateConstInBoundsGEP1_64(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, TD, TLI);
- return StrChr ? B.CreateBitCast(StrChr, CI->getType()) : 0;
- }
- return 0;
+ // 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;
}
-};
+ return nullptr;
+}
-struct MemCmpOpt : public LibCallOptimization {
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- FunctionType *FT = Callee->getFunctionType();
- if (FT->getNumParams() != 3 || !FT->getParamType(0)->isPointerTy() ||
- !FT->getParamType(1)->isPointerTy() ||
- !FT->getReturnType()->isIntegerTy(32))
- return 0;
+Value *LibCallSimplifier::optimizeMemChr(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 3 || !FT->getParamType(0)->isPointerTy() ||
+ !FT->getParamType(1)->isIntegerTy(32) ||
+ !FT->getParamType(2)->isIntegerTy() ||
+ !FT->getReturnType()->isPointerTy())
+ return nullptr;
+
+ Value *SrcStr = CI->getArgOperand(0);
+ ConstantInt *CharC = dyn_cast<ConstantInt>(CI->getArgOperand(1));
+ ConstantInt *LenC = dyn_cast<ConstantInt>(CI->getArgOperand(2));
+
+ // memchr(x, y, 0) -> null
+ if (LenC && LenC->isNullValue())
+ return Constant::getNullValue(CI->getType());
+
+ // From now on we need at least constant length and string.
+ StringRef Str;
+ if (!LenC || !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 -> (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);
+
+ // First check that the bit field access is within bounds.
+ Value *C = B.CreateZExtOrTrunc(CI->getArgOperand(1), BitfieldC->getType());
+ 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());
+ }
- Value *LHS = CI->getArgOperand(0), *RHS = CI->getArgOperand(1);
+ // Check if all arguments are constants. If so, we can constant fold.
+ if (!CharC)
+ return nullptr;
- if (LHS == RHS) // memcmp(s,s,x) -> 0
- return Constant::getNullValue(CI->getType());
+ // 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());
- // Make sure we have a constant length.
- ConstantInt *LenC = dyn_cast<ConstantInt>(CI->getArgOperand(2));
- if (!LenC) return 0;
- uint64_t Len = LenC->getZExtValue();
+ // memchr(s+n,c,l) -> gep(s+n+i,c)
+ return B.CreateGEP(B.getInt8Ty(), SrcStr, B.getInt64(I), "memchr");
+}
- if (Len == 0) // memcmp(s1,s2,0) -> 0
- return Constant::getNullValue(CI->getType());
+Value *LibCallSimplifier::optimizeMemCmp(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 3 || !FT->getParamType(0)->isPointerTy() ||
+ !FT->getParamType(1)->isPointerTy() ||
+ !FT->getReturnType()->isIntegerTy(32))
+ return nullptr;
+
+ Value *LHS = CI->getArgOperand(0), *RHS = CI->getArgOperand(1);
+
+ if (LHS == RHS) // memcmp(s,s,x) -> 0
+ return Constant::getNullValue(CI->getType());
+
+ // Make sure we have a constant length.
+ ConstantInt *LenC = dyn_cast<ConstantInt>(CI->getArgOperand(2));
+ if (!LenC)
+ return nullptr;
+ uint64_t Len = LenC->getZExtValue();
+
+ 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(CastToCStr(LHS, B), "lhsc"),
+ CI->getType(), "lhsv");
+ Value *RHSV = B.CreateZExt(B.CreateLoad(CastToCStr(RHS, B), "rhsc"),
+ CI->getType(), "rhsv");
+ return B.CreateSub(LHSV, RHSV, "chardiff");
+ }
- // memcmp(S1,S2,1) -> *(unsigned char*)LHS - *(unsigned char*)RHS
- if (Len == 1) {
- Value *LHSV = B.CreateZExt(B.CreateLoad(CastToCStr(LHS, B), "lhsc"),
- CI->getType(), "lhsv");
- Value *RHSV = B.CreateZExt(B.CreateLoad(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
+ if (DL.isLegalInteger(Len * 8) && isOnlyUsedInZeroEqualityComparison(CI)) {
- // Constant folding: memcmp(x, y, l) -> cnst (all arguments are constant)
- 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 0;
- // 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);
+ IntegerType *IntType = IntegerType::get(CI->getContext(), Len * 8);
+ unsigned PrefAlignment = DL.getPrefTypeAlignment(IntType);
+
+ if (getKnownAlignment(LHS, DL, CI) >= PrefAlignment &&
+ getKnownAlignment(RHS, DL, CI) >= PrefAlignment) {
+
+ Type *LHSPtrTy =
+ IntType->getPointerTo(LHS->getType()->getPointerAddressSpace());
+ Type *RHSPtrTy =
+ IntType->getPointerTo(RHS->getType()->getPointerAddressSpace());
+
+ Value *LHSV = B.CreateLoad(B.CreateBitCast(LHS, LHSPtrTy, "lhsc"), "lhsv");
+ Value *RHSV = B.CreateLoad(B.CreateBitCast(RHS, RHSPtrTy, "rhsc"), "rhsv");
+
+ return B.CreateZExt(B.CreateICmpNE(LHSV, RHSV), CI->getType(), "memcmp");
}
+ }
- return 0;
+ // Constant folding: memcmp(x, y, l) -> cnst (all arguments are constant)
+ 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);
}
-};
-struct MemCpyOpt : public LibCallOptimization {
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- // These optimizations require DataLayout.
- if (!TD) return 0;
+ return nullptr;
+}
- FunctionType *FT = Callee->getFunctionType();
- if (FT->getNumParams() != 3 || FT->getReturnType() != FT->getParamType(0) ||
- !FT->getParamType(0)->isPointerTy() ||
- !FT->getParamType(1)->isPointerTy() ||
- FT->getParamType(2) != TD->getIntPtrType(*Context))
- return 0;
+Value *LibCallSimplifier::optimizeMemCpy(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
- // memcpy(x, y, n) -> llvm.memcpy(x, y, n, 1)
- B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(1),
- CI->getArgOperand(2), 1);
- return CI->getArgOperand(0);
- }
-};
+ if (!checkStringCopyLibFuncSignature(Callee, LibFunc::memcpy))
+ return nullptr;
+
+ // memcpy(x, y, n) -> llvm.memcpy(x, y, n, 1)
+ B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(1),
+ CI->getArgOperand(2), 1);
+ return CI->getArgOperand(0);
+}
-struct MemMoveOpt : public LibCallOptimization {
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- // These optimizations require DataLayout.
- if (!TD) return 0;
+Value *LibCallSimplifier::optimizeMemMove(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
- FunctionType *FT = Callee->getFunctionType();
- if (FT->getNumParams() != 3 || FT->getReturnType() != FT->getParamType(0) ||
- !FT->getParamType(0)->isPointerTy() ||
- !FT->getParamType(1)->isPointerTy() ||
- FT->getParamType(2) != TD->getIntPtrType(*Context))
- return 0;
+ if (!checkStringCopyLibFuncSignature(Callee, LibFunc::memmove))
+ return nullptr;
- // memmove(x, y, n) -> llvm.memmove(x, y, n, 1)
- B.CreateMemMove(CI->getArgOperand(0), CI->getArgOperand(1),
- CI->getArgOperand(2), 1);
- return CI->getArgOperand(0);
- }
-};
+ // memmove(x, y, n) -> llvm.memmove(x, y, n, 1)
+ B.CreateMemMove(CI->getArgOperand(0), CI->getArgOperand(1),
+ CI->getArgOperand(2), 1);
+ return CI->getArgOperand(0);
+}
-struct MemSetOpt : public LibCallOptimization {
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- // These optimizations require DataLayout.
- if (!TD) return 0;
+Value *LibCallSimplifier::optimizeMemSet(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
- FunctionType *FT = Callee->getFunctionType();
- if (FT->getNumParams() != 3 || FT->getReturnType() != FT->getParamType(0) ||
- !FT->getParamType(0)->isPointerTy() ||
- !FT->getParamType(1)->isIntegerTy() ||
- FT->getParamType(2) != TD->getIntPtrType(*Context))
- return 0;
+ if (!checkStringCopyLibFuncSignature(Callee, LibFunc::memset))
+ return nullptr;
- // memset(p, v, n) -> llvm.memset(p, v, n, 1)
- Value *Val = B.CreateIntCast(CI->getArgOperand(1), B.getInt8Ty(), false);
- B.CreateMemSet(CI->getArgOperand(0), Val, CI->getArgOperand(2), 1);
- return CI->getArgOperand(0);
- }
-};
+ // memset(p, v, n) -> llvm.memset(p, v, n, 1)
+ Value *Val = B.CreateIntCast(CI->getArgOperand(1), B.getInt8Ty(), false);
+ B.CreateMemSet(CI->getArgOperand(0), Val, CI->getArgOperand(2), 1);
+ return CI->getArgOperand(0);
+}
//===----------------------------------------------------------------------===//
// Math Library Optimizations
//===----------------------------------------------------------------------===//
+/// 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;
+}
+
//===----------------------------------------------------------------------===//
// Double -> Float Shrinking Optimizations for Unary Functions like 'floor'
-struct UnaryDoubleFPOpt : public LibCallOptimization {
- bool CheckRetType;
- UnaryDoubleFPOpt(bool CheckReturnType): CheckRetType(CheckReturnType) {}
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- FunctionType *FT = Callee->getFunctionType();
- if (FT->getNumParams() != 1 || !FT->getReturnType()->isDoubleTy() ||
- !FT->getParamType(0)->isDoubleTy())
- return 0;
-
- if (CheckRetType) {
- // Check if all the uses for function like 'sin' are converted to float.
- for (Value::use_iterator UseI = CI->use_begin(); UseI != CI->use_end();
- ++UseI) {
- FPTruncInst *Cast = dyn_cast<FPTruncInst>(*UseI);
- if (Cast == 0 || !Cast->getType()->isFloatTy())
- return 0;
- }
+Value *LibCallSimplifier::optimizeUnaryDoubleFP(CallInst *CI, IRBuilder<> &B,
+ bool CheckRetType) {
+ Function *Callee = CI->getCalledFunction();
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 1 || !FT->getReturnType()->isDoubleTy() ||
+ !FT->getParamType(0)->isDoubleTy())
+ return nullptr;
+
+ if (CheckRetType) {
+ // Check if all the uses for function like 'sin' are converted to float.
+ for (User *U : CI->users()) {
+ FPTruncInst *Cast = dyn_cast<FPTruncInst>(U);
+ if (!Cast || !Cast->getType()->isFloatTy())
+ return nullptr;
}
-
- // If this is something like 'floor((double)floatval)', convert to floorf.
- FPExtInst *Cast = dyn_cast<FPExtInst>(CI->getArgOperand(0));
- if (Cast == 0 || !Cast->getOperand(0)->getType()->isFloatTy())
- return 0;
-
- // floor((double)floatval) -> (double)floorf(floatval)
- Value *V = Cast->getOperand(0);
- V = EmitUnaryFloatFnCall(V, Callee->getName(), B, Callee->getAttributes());
- return B.CreateFPExt(V, B.getDoubleTy());
}
-};
-struct UnsafeFPLibCallOptimization : public LibCallOptimization {
- bool UnsafeFPShrink;
- UnsafeFPLibCallOptimization(bool UnsafeFPShrink) {
- this->UnsafeFPShrink = UnsafeFPShrink;
+ // If this is something like 'floor((double)floatval)', convert to floorf.
+ Value *V = valueHasFloatPrecision(CI->getArgOperand(0));
+ if (V == nullptr)
+ return nullptr;
+
+ // floor((double)floatval) -> (double)floorf(floatval)
+ if (Callee->isIntrinsic()) {
+ Module *M = CI->getParent()->getParent()->getParent();
+ Intrinsic::ID IID = Callee->getIntrinsicID();
+ Function *F = Intrinsic::getDeclaration(M, IID, B.getFloatTy());
+ V = B.CreateCall(F, V);
+ } else {
+ // The call is a library call rather than an intrinsic.
+ V = EmitUnaryFloatFnCall(V, Callee->getName(), B, Callee->getAttributes());
}
-};
-struct CosOpt : public UnsafeFPLibCallOptimization {
- CosOpt(bool UnsafeFPShrink) : UnsafeFPLibCallOptimization(UnsafeFPShrink) {}
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- Value *Ret = NULL;
- if (UnsafeFPShrink && Callee->getName() == "cos" &&
- TLI->has(LibFunc::cosf)) {
- UnaryDoubleFPOpt UnsafeUnaryDoubleFP(true);
- Ret = UnsafeUnaryDoubleFP.callOptimizer(Callee, CI, B);
- }
+ return B.CreateFPExt(V, B.getDoubleTy());
+}
- FunctionType *FT = Callee->getFunctionType();
- // Just make sure this has 1 argument of FP type, which matches the
- // result type.
- if (FT->getNumParams() != 1 || FT->getReturnType() != FT->getParamType(0) ||
- !FT->getParamType(0)->isFloatingPointTy())
- return Ret;
+// Double -> Float Shrinking Optimizations for Binary Functions like 'fmin/fmax'
+Value *LibCallSimplifier::optimizeBinaryDoubleFP(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
+ FunctionType *FT = Callee->getFunctionType();
+ // Just make sure this has 2 arguments of the same FP type, which match the
+ // result type.
+ if (FT->getNumParams() != 2 || FT->getReturnType() != FT->getParamType(0) ||
+ FT->getParamType(0) != FT->getParamType(1) ||
+ !FT->getParamType(0)->isFloatingPointTy())
+ return nullptr;
+
+ // If this is something like 'fmin((double)floatval1, (double)floatval2)',
+ // or fmin(1.0, (double)floatval), then we convert it to fminf.
+ Value *V1 = valueHasFloatPrecision(CI->getArgOperand(0));
+ if (V1 == nullptr)
+ return nullptr;
+ Value *V2 = valueHasFloatPrecision(CI->getArgOperand(1));
+ if (V2 == nullptr)
+ return nullptr;
+
+ // fmin((double)floatval1, (double)floatval2)
+ // -> (double)fminf(floatval1, floatval2)
+ // TODO: Handle intrinsics in the same way as in optimizeUnaryDoubleFP().
+ Value *V = EmitBinaryFloatFnCall(V1, V2, Callee->getName(), B,
+ Callee->getAttributes());
+ return B.CreateFPExt(V, B.getDoubleTy());
+}
- // cos(-x) -> cos(x)
- Value *Op1 = CI->getArgOperand(0);
- if (BinaryOperator::isFNeg(Op1)) {
- BinaryOperator *BinExpr = cast<BinaryOperator>(Op1);
- return B.CreateCall(Callee, BinExpr->getOperand(1), "cos");
- }
+Value *LibCallSimplifier::optimizeCos(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
+ Value *Ret = nullptr;
+ StringRef Name = Callee->getName();
+ if (UnsafeFPShrink && Name == "cos" && hasFloatVersion(Name))
+ Ret = optimizeUnaryDoubleFP(CI, B, true);
+
+ FunctionType *FT = Callee->getFunctionType();
+ // Just make sure this has 1 argument of FP type, which matches the
+ // result type.
+ if (FT->getNumParams() != 1 || FT->getReturnType() != FT->getParamType(0) ||
+ !FT->getParamType(0)->isFloatingPointTy())
return Ret;
+
+ // cos(-x) -> cos(x)
+ Value *Op1 = CI->getArgOperand(0);
+ if (BinaryOperator::isFNeg(Op1)) {
+ BinaryOperator *BinExpr = cast<BinaryOperator>(Op1);
+ return B.CreateCall(Callee, BinExpr->getOperand(1), "cos");
}
-};
+ return Ret;
+}
-struct PowOpt : public UnsafeFPLibCallOptimization {
- PowOpt(bool UnsafeFPShrink) : UnsafeFPLibCallOptimization(UnsafeFPShrink) {}
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- Value *Ret = NULL;
- if (UnsafeFPShrink && Callee->getName() == "pow" &&
- TLI->has(LibFunc::powf)) {
- UnaryDoubleFPOpt UnsafeUnaryDoubleFP(true);
- Ret = UnsafeUnaryDoubleFP.callOptimizer(Callee, CI, B);
- }
+Value *LibCallSimplifier::optimizePow(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
+ Value *Ret = nullptr;
+ StringRef Name = Callee->getName();
+ if (UnsafeFPShrink && Name == "pow" && hasFloatVersion(Name))
+ Ret = optimizeUnaryDoubleFP(CI, B, true);
+
+ FunctionType *FT = Callee->getFunctionType();
+ // Just make sure this has 2 arguments of the same FP type, which match the
+ // result type.
+ if (FT->getNumParams() != 2 || FT->getReturnType() != FT->getParamType(0) ||
+ FT->getParamType(0) != FT->getParamType(1) ||
+ !FT->getParamType(0)->isFloatingPointTy())
+ return Ret;
- FunctionType *FT = Callee->getFunctionType();
- // Just make sure this has 2 arguments of the same FP type, which match the
- // result type.
- if (FT->getNumParams() != 2 || FT->getReturnType() != FT->getParamType(0) ||
- FT->getParamType(0) != FT->getParamType(1) ||
- !FT->getParamType(0)->isFloatingPointTy())
- return Ret;
+ Value *Op1 = CI->getArgOperand(0), *Op2 = CI->getArgOperand(1);
+ if (ConstantFP *Op1C = dyn_cast<ConstantFP>(Op1)) {
+ // pow(1.0, x) -> 1.0
+ if (Op1C->isExactlyValue(1.0))
+ return Op1C;
+ // pow(2.0, x) -> exp2(x)
+ if (Op1C->isExactlyValue(2.0) &&
+ hasUnaryFloatFn(TLI, Op1->getType(), LibFunc::exp2, LibFunc::exp2f,
+ LibFunc::exp2l))
+ return EmitUnaryFloatFnCall(Op2, "exp2", B, Callee->getAttributes());
+ // pow(10.0, x) -> exp10(x)
+ if (Op1C->isExactlyValue(10.0) &&
+ hasUnaryFloatFn(TLI, Op1->getType(), LibFunc::exp10, LibFunc::exp10f,
+ LibFunc::exp10l))
+ return EmitUnaryFloatFnCall(Op2, TLI->getName(LibFunc::exp10), B,
+ Callee->getAttributes());
+ }
- Value *Op1 = CI->getArgOperand(0), *Op2 = CI->getArgOperand(1);
- if (ConstantFP *Op1C = dyn_cast<ConstantFP>(Op1)) {
- if (Op1C->isExactlyValue(1.0)) // pow(1.0, x) -> 1.0
- return Op1C;
- if (Op1C->isExactlyValue(2.0)) // pow(2.0, x) -> exp2(x)
- return EmitUnaryFloatFnCall(Op2, "exp2", B, Callee->getAttributes());
+ // pow(exp(x), y) -> exp(x*y)
+ // pow(exp2(x), y) -> exp2(x * y)
+ // We enable these only under fast-math. Besides rounding
+ // differences the transformation changes overflow and
+ // underflow behavior quite dramatically.
+ // Example: x = 1000, y = 0.001.
+ // pow(exp(x), y) = pow(inf, 0.001) = inf, whereas exp(x*y) = exp(1).
+ if (canUseUnsafeFPMath(CI->getParent()->getParent())) {
+ if (auto *OpC = dyn_cast<CallInst>(Op1)) {
+ IRBuilder<>::FastMathFlagGuard Guard(B);
+ FastMathFlags FMF;
+ FMF.setUnsafeAlgebra();
+ B.SetFastMathFlags(FMF);
+
+ LibFunc::Func Func;
+ Function *Callee = OpC->getCalledFunction();
+ StringRef FuncName = Callee->getName();
+
+ if (TLI->getLibFunc(FuncName, Func) && TLI->has(Func) &&
+ (Func == LibFunc::exp || Func == LibFunc::exp2))
+ return EmitUnaryFloatFnCall(
+ B.CreateFMul(OpC->getArgOperand(0), Op2, "mul"), FuncName, B,
+ Callee->getAttributes());
}
+ }
- ConstantFP *Op2C = dyn_cast<ConstantFP>(Op2);
- if (Op2C == 0) return Ret;
-
- if (Op2C->getValueAPF().isZero()) // pow(x, 0.0) -> 1.0
- return ConstantFP::get(CI->getType(), 1.0);
-
- if (Op2C->isExactlyValue(0.5)) {
- // Expand pow(x, 0.5) to (x == -infinity ? +infinity : fabs(sqrt(x))).
- // This is faster than calling pow, and still handles negative zero
- // and negative infinity correctly.
- // TODO: In fast-math mode, this could be just sqrt(x).
- // TODO: In finite-only mode, this could be just fabs(sqrt(x)).
- Value *Inf = ConstantFP::getInfinity(CI->getType());
- Value *NegInf = ConstantFP::getInfinity(CI->getType(), true);
- Value *Sqrt = EmitUnaryFloatFnCall(Op1, "sqrt", B,
- Callee->getAttributes());
- Value *FAbs = EmitUnaryFloatFnCall(Sqrt, "fabs", B,
- Callee->getAttributes());
- Value *FCmp = B.CreateFCmpOEQ(Op1, NegInf);
- Value *Sel = B.CreateSelect(FCmp, Inf, FAbs);
- return Sel;
- }
+ ConstantFP *Op2C = dyn_cast<ConstantFP>(Op2);
+ if (!Op2C)
+ return Ret;
- if (Op2C->isExactlyValue(1.0)) // pow(x, 1.0) -> x
- return Op1;
- if (Op2C->isExactlyValue(2.0)) // pow(x, 2.0) -> x*x
- return B.CreateFMul(Op1, Op1, "pow2");
- if (Op2C->isExactlyValue(-1.0)) // pow(x, -1.0) -> 1.0/x
- return B.CreateFDiv(ConstantFP::get(CI->getType(), 1.0),
- Op1, "powrecip");
- return 0;
- }
-};
-
-struct Exp2Opt : public UnsafeFPLibCallOptimization {
- Exp2Opt(bool UnsafeFPShrink) : UnsafeFPLibCallOptimization(UnsafeFPShrink) {}
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- Value *Ret = NULL;
- if (UnsafeFPShrink && Callee->getName() == "exp2" &&
- TLI->has(LibFunc::exp2)) {
- UnaryDoubleFPOpt UnsafeUnaryDoubleFP(true);
- Ret = UnsafeUnaryDoubleFP.callOptimizer(Callee, CI, B);
- }
+ if (Op2C->getValueAPF().isZero()) // pow(x, 0.0) -> 1.0
+ return ConstantFP::get(CI->getType(), 1.0);
+
+ if (Op2C->isExactlyValue(0.5) &&
+ hasUnaryFloatFn(TLI, Op2->getType(), LibFunc::sqrt, LibFunc::sqrtf,
+ LibFunc::sqrtl) &&
+ hasUnaryFloatFn(TLI, Op2->getType(), LibFunc::fabs, LibFunc::fabsf,
+ LibFunc::fabsl)) {
+ // Expand pow(x, 0.5) to (x == -infinity ? +infinity : fabs(sqrt(x))).
+ // This is faster than calling pow, and still handles negative zero
+ // and negative infinity correctly.
+ // TODO: In fast-math mode, this could be just sqrt(x).
+ // TODO: In finite-only mode, this could be just fabs(sqrt(x)).
+ Value *Inf = ConstantFP::getInfinity(CI->getType());
+ Value *NegInf = ConstantFP::getInfinity(CI->getType(), true);
+ Value *Sqrt = EmitUnaryFloatFnCall(Op1, "sqrt", B, Callee->getAttributes());
+ Value *FAbs =
+ EmitUnaryFloatFnCall(Sqrt, "fabs", B, Callee->getAttributes());
+ Value *FCmp = B.CreateFCmpOEQ(Op1, NegInf);
+ Value *Sel = B.CreateSelect(FCmp, Inf, FAbs);
+ return Sel;
+ }
- FunctionType *FT = Callee->getFunctionType();
- // Just make sure this has 1 argument of FP type, which matches the
- // result type.
- if (FT->getNumParams() != 1 || FT->getReturnType() != FT->getParamType(0) ||
- !FT->getParamType(0)->isFloatingPointTy())
- return Ret;
+ if (Op2C->isExactlyValue(1.0)) // pow(x, 1.0) -> x
+ return Op1;
+ if (Op2C->isExactlyValue(2.0)) // pow(x, 2.0) -> x*x
+ return B.CreateFMul(Op1, Op1, "pow2");
+ if (Op2C->isExactlyValue(-1.0)) // pow(x, -1.0) -> 1.0/x
+ return B.CreateFDiv(ConstantFP::get(CI->getType(), 1.0), Op1, "powrecip");
+ return nullptr;
+}
- 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
- Value *LdExpArg = 0;
+Value *LibCallSimplifier::optimizeExp2(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
+ Function *Caller = CI->getParent()->getParent();
+ Value *Ret = nullptr;
+ StringRef Name = Callee->getName();
+ if (UnsafeFPShrink && Name == "exp2" && hasFloatVersion(Name))
+ Ret = optimizeUnaryDoubleFP(CI, B, true);
+
+ FunctionType *FT = Callee->getFunctionType();
+ // Just make sure this has 1 argument of FP type, which matches the
+ // result type.
+ if (FT->getNumParams() != 1 || FT->getReturnType() != FT->getParamType(0) ||
+ !FT->getParamType(0)->isFloatingPointTy())
+ return Ret;
+
+ 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
+ LibFunc::Func LdExp = LibFunc::ldexpl;
+ if (Op->getType()->isFloatTy())
+ LdExp = LibFunc::ldexpf;
+ else if (Op->getType()->isDoubleTy())
+ LdExp = LibFunc::ldexp;
+
+ if (TLI->has(LdExp)) {
+ Value *LdExpArg = nullptr;
if (SIToFPInst *OpC = dyn_cast<SIToFPInst>(Op)) {
if (OpC->getOperand(0)->getType()->getPrimitiveSizeInBits() <= 32)
LdExpArg = B.CreateSExt(OpC->getOperand(0), B.getInt32Ty());
}
if (LdExpArg) {
- const char *Name;
- if (Op->getType()->isFloatTy())
- Name = "ldexpf";
- else if (Op->getType()->isDoubleTy())
- Name = "ldexp";
- else
- Name = "ldexpl";
-
- Constant *One = ConstantFP::get(*Context, APFloat(1.0f));
+ Constant *One = ConstantFP::get(CI->getContext(), APFloat(1.0f));
if (!Op->getType()->isFloatTy())
One = ConstantExpr::getFPExtend(One, Op->getType());
Module *M = Caller->getParent();
- Value *Callee = M->getOrInsertFunction(Name, Op->getType(),
- Op->getType(),
- B.getInt32Ty(), NULL);
- CallInst *CI = B.CreateCall2(Callee, One, LdExpArg);
+ Value *Callee =
+ M->getOrInsertFunction(TLI->getName(LdExp), Op->getType(),
+ Op->getType(), B.getInt32Ty(), nullptr);
+ CallInst *CI = B.CreateCall(Callee, {One, LdExpArg});
if (const Function *F = dyn_cast<Function>(Callee->stripPointerCasts()))
CI->setCallingConv(F->getCallingConv());
return CI;
}
+ }
+ return Ret;
+}
+
+Value *LibCallSimplifier::optimizeFabs(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
+ Value *Ret = nullptr;
+ StringRef Name = Callee->getName();
+ if (Name == "fabs" && hasFloatVersion(Name))
+ Ret = optimizeUnaryDoubleFP(CI, B, false);
+
+ FunctionType *FT = Callee->getFunctionType();
+ // Make sure this has 1 argument of FP type which matches the result type.
+ if (FT->getNumParams() != 1 || FT->getReturnType() != FT->getParamType(0) ||
+ !FT->getParamType(0)->isFloatingPointTy())
return Ret;
+
+ Value *Op = CI->getArgOperand(0);
+ if (Instruction *I = dyn_cast<Instruction>(Op)) {
+ // Fold fabs(x * x) -> x * x; any squared FP value must already be positive.
+ if (I->getOpcode() == Instruction::FMul)
+ if (I->getOperand(0) == I->getOperand(1))
+ return Op;
+ }
+ return Ret;
+}
+
+Value *LibCallSimplifier::optimizeFMinFMax(CallInst *CI, IRBuilder<> &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" && hasFloatVersion(Name)) ||
+ (Name == "fmax" && hasFloatVersion(Name))) {
+ Value *Ret = optimizeBinaryDoubleFP(CI, B);
+ if (Ret)
+ return Ret;
+ }
+
+ // Make sure this has 2 arguments of FP type which match the result type.
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 2 || FT->getReturnType() != FT->getParamType(0) ||
+ FT->getParamType(0) != FT->getParamType(1) ||
+ !FT->getParamType(0)->isFloatingPointTy())
+ return nullptr;
+
+ IRBuilder<>::FastMathFlagGuard Guard(B);
+ FastMathFlags FMF;
+ Function *F = CI->getParent()->getParent();
+ if (canUseUnsafeFPMath(F)) {
+ // Unsafe algebra sets all fast-math-flags to true.
+ FMF.setUnsafeAlgebra();
+ } else {
+ // At a minimum, no-nans-fp-math must be true.
+ Attribute Attr = F->getFnAttribute("no-nans-fp-math");
+ if (Attr.getValueAsString() != "true")
+ return nullptr;
+ // No-signed-zeros is implied by the definitions of fmax/fmin themselves:
+ // "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."
+ FMF.setNoSignedZeros();
+ FMF.setNoNaNs();
+ }
+ B.SetFastMathFlags(FMF);
+
+ // We have a relaxed floating-point environment. We can ignore NaN-handling
+ // and transform to a compare and select. We do not have to consider errno or
+ // exceptions, because fmin/fmax do not have those.
+ Value *Op0 = CI->getArgOperand(0);
+ Value *Op1 = CI->getArgOperand(1);
+ Value *Cmp = Callee->getName().startswith("fmin") ?
+ B.CreateFCmpOLT(Op0, Op1) : B.CreateFCmpOGT(Op0, Op1);
+ return B.CreateSelect(Cmp, Op0, Op1);
+}
+
+Value *LibCallSimplifier::optimizeSqrt(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
+
+ Value *Ret = nullptr;
+ if (TLI->has(LibFunc::sqrtf) && (Callee->getName() == "sqrt" ||
+ Callee->getIntrinsicID() == Intrinsic::sqrt))
+ Ret = optimizeUnaryDoubleFP(CI, B, true);
+ if (!canUseUnsafeFPMath(CI->getParent()->getParent()))
+ return Ret;
+
+ Value *Op = CI->getArgOperand(0);
+ if (Instruction *I = dyn_cast<Instruction>(Op)) {
+ if (I->getOpcode() == Instruction::FMul && I->hasUnsafeAlgebra()) {
+ // 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) {
+ // Matched: sqrt((x * x) * z)
+ RepeatOp = OtherMul0;
+ OtherOp = Op1;
+ }
+ }
+ }
+ if (RepeatOp) {
+ // Fast math flags for any created instructions should match the sqrt
+ // and multiply.
+ // FIXME: We're not checking the sqrt because it doesn't have
+ // fast-math-flags (see earlier comment).
+ IRBuilder<>::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 = Op->getType();
+ Value *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.
+ Value *Sqrt = Intrinsic::getDeclaration(M, Intrinsic::sqrt, ArgType);
+ Value *SqrtCall = B.CreateCall(Sqrt, OtherOp, "sqrt");
+ return B.CreateFMul(FabsCall, SqrtCall);
+ }
+ return FabsCall;
+ }
+ }
+ }
+ return Ret;
+}
+
+Value *LibCallSimplifier::optimizeTan(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
+ Value *Ret = nullptr;
+ StringRef Name = Callee->getName();
+ if (UnsafeFPShrink && Name == "tan" && hasFloatVersion(Name))
+ Ret = optimizeUnaryDoubleFP(CI, B, true);
+ FunctionType *FT = Callee->getFunctionType();
+
+ // Just make sure this has 1 argument of FP type, which matches the
+ // result type.
+ if (FT->getNumParams() != 1 || FT->getReturnType() != FT->getParamType(0) ||
+ !FT->getParamType(0)->isFloatingPointTy())
+ return Ret;
+
+ if (!canUseUnsafeFPMath(CI->getParent()->getParent()))
+ return Ret;
+ Value *Op1 = CI->getArgOperand(0);
+ auto *OpC = dyn_cast<CallInst>(Op1);
+ if (!OpC)
+ return Ret;
+
+ // tan(atan(x)) -> x
+ // tanf(atanf(x)) -> x
+ // tanl(atanl(x)) -> x
+ LibFunc::Func Func;
+ Function *F = OpC->getCalledFunction();
+ StringRef FuncName = F->getName();
+ if (TLI->getLibFunc(FuncName, 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);
+static void insertSinCosCall(IRBuilder<> &B, Function *OrigCallee, Value *Arg,
+ bool UseFloat, Value *&Sin, Value *&Cos,
+ Value *&SinCos);
+
+Value *LibCallSimplifier::optimizeSinCosPi(CallInst *CI, IRBuilder<> &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.
+ for (User *U : Arg->users())
+ classifyArgUse(U, CI->getParent(), IsFloat, SinCalls, CosCalls,
+ SinCosCalls);
+
+ // It's only worthwhile if both sinpi and cospi are actually used.
+ if (SinCosCalls.empty() && (SinCalls.empty() || CosCalls.empty()))
+ return nullptr;
+
+ Value *Sin, *Cos, *SinCos;
+ insertSinCosCall(B, CI->getCalledFunction(), Arg, IsFloat, Sin, Cos, SinCos);
+
+ replaceTrigInsts(SinCalls, Sin);
+ replaceTrigInsts(CosCalls, Cos);
+ replaceTrigInsts(SinCosCalls, SinCos);
+
+ return nullptr;
+}
+
+static bool isTrigLibCall(CallInst *CI) {
+ Function *Callee = CI->getCalledFunction();
+ FunctionType *FT = Callee->getFunctionType();
+
+ // We can only hope to do anything useful if we can ignore things like errno
+ // and floating-point exceptions.
+ bool AttributesSafe =
+ CI->hasFnAttr(Attribute::NoUnwind) && CI->hasFnAttr(Attribute::ReadNone);
+
+ // Other than that we need float(float) or double(double)
+ return AttributesSafe && FT->getNumParams() == 1 &&
+ FT->getReturnType() == FT->getParamType(0) &&
+ (FT->getParamType(0)->isFloatTy() ||
+ FT->getParamType(0)->isDoubleTy());
+}
+
+void
+LibCallSimplifier::classifyArgUse(Value *Val, BasicBlock *BB, bool IsFloat,
+ SmallVectorImpl<CallInst *> &SinCalls,
+ SmallVectorImpl<CallInst *> &CosCalls,
+ SmallVectorImpl<CallInst *> &SinCosCalls) {
+ CallInst *CI = dyn_cast<CallInst>(Val);
+
+ if (!CI)
+ return;
+
+ Function *Callee = CI->getCalledFunction();
+ StringRef FuncName = Callee->getName();
+ LibFunc::Func Func;
+ if (!TLI->getLibFunc(FuncName, 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);
+ }
+}
+
+void LibCallSimplifier::replaceTrigInsts(SmallVectorImpl<CallInst *> &Calls,
+ Value *Res) {
+ for (CallInst *C : Calls)
+ replaceAllUsesWith(C, Res);
+}
+
+void insertSinCosCall(IRBuilder<> &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 *>(VectorType::get(ArgTy, 2))
+ : static_cast<Type *>(StructType::get(ArgTy, ArgTy, nullptr));
+ } else {
+ Name = "__sincospi_stret";
+ ResTy = StructType::get(ArgTy, ArgTy, nullptr);
+ }
+
+ Module *M = OrigCallee->getParent();
+ Value *Callee = M->getOrInsertFunction(Name, OrigCallee->getAttributes(),
+ ResTy, ArgTy, nullptr);
+
+ 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");
}
-};
+}
//===----------------------------------------------------------------------===//
// Integer Library Call Optimizations
//===----------------------------------------------------------------------===//
-struct FFSOpt : public LibCallOptimization {
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- FunctionType *FT = Callee->getFunctionType();
- // Just make sure this has 2 arguments of the same FP type, which match the
- // result type.
- if (FT->getNumParams() != 1 ||
- !FT->getReturnType()->isIntegerTy(32) ||
- !FT->getParamType(0)->isIntegerTy())
- return 0;
-
- Value *Op = CI->getArgOperand(0);
-
- // Constant fold.
- if (ConstantInt *CI = dyn_cast<ConstantInt>(Op)) {
- if (CI->isZero()) // ffs(0) -> 0.
- return B.getInt32(0);
- // ffs(c) -> cttz(c)+1
- return B.getInt32(CI->getValue().countTrailingZeros() + 1);
- }
+static bool checkIntUnaryReturnAndParam(Function *Callee) {
+ FunctionType *FT = Callee->getFunctionType();
+ return FT->getNumParams() == 1 && FT->getReturnType()->isIntegerTy(32) &&
+ FT->getParamType(0)->isIntegerTy();
+}
+
+Value *LibCallSimplifier::optimizeFFS(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
+ if (!checkIntUnaryReturnAndParam(Callee))
+ return nullptr;
+ Value *Op = CI->getArgOperand(0);
+
+ // Constant fold.
+ if (ConstantInt *CI = dyn_cast<ConstantInt>(Op)) {
+ if (CI->isZero()) // ffs(0) -> 0.
+ return B.getInt32(0);
+ // ffs(c) -> cttz(c)+1
+ return B.getInt32(CI->getValue().countTrailingZeros() + 1);
+ }
- // ffs(x) -> x != 0 ? (i32)llvm.cttz(x)+1 : 0
- Type *ArgType = Op->getType();
- Value *F = Intrinsic::getDeclaration(Callee->getParent(),
- Intrinsic::cttz, ArgType);
- Value *V = B.CreateCall2(F, Op, B.getFalse(), "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));
- }
-};
-
-struct AbsOpt : public LibCallOptimization {
- virtual bool ignoreCallingConv() { return true; }
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- FunctionType *FT = Callee->getFunctionType();
- // We require integer(integer) where the types agree.
- if (FT->getNumParams() != 1 || !FT->getReturnType()->isIntegerTy() ||
- FT->getParamType(0) != FT->getReturnType())
- return 0;
-
- // abs(x) -> x >s -1 ? x : -x
- Value *Op = CI->getArgOperand(0);
- Value *Pos = B.CreateICmpSGT(Op, Constant::getAllOnesValue(Op->getType()),
- "ispos");
- Value *Neg = B.CreateNeg(Op, "neg");
- return B.CreateSelect(Pos, Op, Neg);
- }
-};
-
-struct IsDigitOpt : public LibCallOptimization {
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- FunctionType *FT = Callee->getFunctionType();
- // We require integer(i32)
- if (FT->getNumParams() != 1 || !FT->getReturnType()->isIntegerTy() ||
- !FT->getParamType(0)->isIntegerTy(32))
- return 0;
-
- // 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());
- }
-};
-
-struct IsAsciiOpt : public LibCallOptimization {
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- FunctionType *FT = Callee->getFunctionType();
- // We require integer(i32)
- if (FT->getNumParams() != 1 || !FT->getReturnType()->isIntegerTy() ||
- !FT->getParamType(0)->isIntegerTy(32))
- return 0;
-
- // isascii(c) -> c <u 128
- Value *Op = CI->getArgOperand(0);
- Op = B.CreateICmpULT(Op, B.getInt32(128), "isascii");
- return B.CreateZExt(Op, CI->getType());
- }
-};
-
-struct ToAsciiOpt : public LibCallOptimization {
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- FunctionType *FT = Callee->getFunctionType();
- // We require i32(i32)
- if (FT->getNumParams() != 1 || FT->getReturnType() != FT->getParamType(0) ||
- !FT->getParamType(0)->isIntegerTy(32))
- return 0;
-
- // toascii(c) -> c & 0x7f
- return B.CreateAnd(CI->getArgOperand(0),
- ConstantInt::get(CI->getType(),0x7F));
- }
-};
+ // ffs(x) -> x != 0 ? (i32)llvm.cttz(x)+1 : 0
+ Type *ArgType = Op->getType();
+ Value *F =
+ Intrinsic::getDeclaration(Callee->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::optimizeAbs(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
+ FunctionType *FT = Callee->getFunctionType();
+ // We require integer(integer) where the types agree.
+ if (FT->getNumParams() != 1 || !FT->getReturnType()->isIntegerTy() ||
+ FT->getParamType(0) != FT->getReturnType())
+ return nullptr;
+
+ // abs(x) -> x >s -1 ? x : -x
+ Value *Op = CI->getArgOperand(0);
+ Value *Pos =
+ B.CreateICmpSGT(Op, Constant::getAllOnesValue(Op->getType()), "ispos");
+ Value *Neg = B.CreateNeg(Op, "neg");
+ return B.CreateSelect(Pos, Op, Neg);
+}
+
+Value *LibCallSimplifier::optimizeIsDigit(CallInst *CI, IRBuilder<> &B) {
+ if (!checkIntUnaryReturnAndParam(CI->getCalledFunction()))
+ return nullptr;
+
+ // 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, IRBuilder<> &B) {
+ if (!checkIntUnaryReturnAndParam(CI->getCalledFunction()))
+ return nullptr;
+
+ // 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, IRBuilder<> &B) {
+ if (!checkIntUnaryReturnAndParam(CI->getCalledFunction()))
+ return nullptr;
+
+ // toascii(c) -> c & 0x7f
+ return B.CreateAnd(CI->getArgOperand(0),
+ ConstantInt::get(CI->getType(), 0x7F));
+}
//===----------------------------------------------------------------------===//
// Formatting and IO Library Call Optimizations
//===----------------------------------------------------------------------===//
-struct PrintFOpt : public LibCallOptimization {
- Value *optimizeFixedFormatString(Function *Callee, CallInst *CI,
- IRBuilder<> &B) {
- // Check for a fixed format string.
- StringRef FormatStr;
- if (!getConstantStringInfo(CI->getArgOperand(0), FormatStr))
- return 0;
-
- // 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 0;
-
- // printf("x") -> putchar('x'), even for '%'.
- if (FormatStr.size() == 1) {
- Value *Res = EmitPutChar(B.getInt32(FormatStr[0]), B, TD, TLI);
- if (CI->use_empty() || !Res) return Res;
- return B.CreateIntCast(Res, CI->getType(), true);
- }
+static bool isReportingError(Function *Callee, CallInst *CI, int StreamArg);
- // printf("foo\n") --> puts("foo")
- if (FormatStr[FormatStr.size()-1] == '\n' &&
- FormatStr.find('%') == std::string::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");
- Value *NewCI = EmitPutS(GV, B, TD, TLI);
- return (CI->use_empty() || !NewCI) ?
- NewCI :
- ConstantInt::get(CI->getType(), FormatStr.size()+1);
- }
+Value *LibCallSimplifier::optimizeErrorReporting(CallInst *CI, IRBuilder<> &B,
+ int StreamArg) {
+ // 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.
- // Optimize specific format strings.
- // printf("%c", chr) --> putchar(chr)
- if (FormatStr == "%c" && CI->getNumArgOperands() > 1 &&
- CI->getArgOperand(1)->getType()->isIntegerTy()) {
- Value *Res = EmitPutChar(CI->getArgOperand(1), B, TD, TLI);
+ // 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
+ Function *Callee = CI->getCalledFunction();
- if (CI->use_empty() || !Res) return Res;
- return B.CreateIntCast(Res, CI->getType(), true);
- }
+ if (!CI->hasFnAttr(Attribute::Cold) &&
+ isReportingError(Callee, CI, StreamArg)) {
+ CI->addAttribute(AttributeSet::FunctionIndex, Attribute::Cold);
+ }
- // printf("%s\n", str) --> puts(str)
- if (FormatStr == "%s\n" && CI->getNumArgOperands() > 1 &&
- CI->getArgOperand(1)->getType()->isPointerTy()) {
- return EmitPutS(CI->getArgOperand(1), B, TD, TLI);
- }
- return 0;
+ return nullptr;
+}
+
+static bool isReportingError(Function *Callee, CallInst *CI, int StreamArg) {
+ if (!ColdErrorCalls || !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, IRBuilder<> &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 '%'.
+ if (FormatStr.size() == 1) {
+ Value *Res = EmitPutChar(B.getInt32(FormatStr[0]), B, TLI);
+ if (CI->use_empty() || !Res)
+ return Res;
+ return B.CreateIntCast(Res, CI->getType(), true);
}
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- // Require one fixed pointer argument and an integer/void result.
- FunctionType *FT = Callee->getFunctionType();
- if (FT->getNumParams() < 1 || !FT->getParamType(0)->isPointerTy() ||
- !(FT->getReturnType()->isIntegerTy() ||
- FT->getReturnType()->isVoidTy()))
- return 0;
+ // 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");
+ Value *NewCI = EmitPutS(GV, B, TLI);
+ return (CI->use_empty() || !NewCI)
+ ? NewCI
+ : ConstantInt::get(CI->getType(), FormatStr.size() + 1);
+ }
- if (Value *V = optimizeFixedFormatString(Callee, CI, B)) {
- return V;
- }
+ // Optimize specific format strings.
+ // printf("%c", chr) --> putchar(chr)
+ if (FormatStr == "%c" && CI->getNumArgOperands() > 1 &&
+ CI->getArgOperand(1)->getType()->isIntegerTy()) {
+ Value *Res = EmitPutChar(CI->getArgOperand(1), B, TLI);
- // printf(format, ...) -> iprintf(format, ...) if no floating point
- // arguments.
- if (TLI->has(LibFunc::iprintf) && !callHasFloatingPointArgument(CI)) {
- Module *M = B.GetInsertBlock()->getParent()->getParent();
- Constant *IPrintFFn =
- M->getOrInsertFunction("iprintf", FT, Callee->getAttributes());
- CallInst *New = cast<CallInst>(CI->clone());
- New->setCalledFunction(IPrintFFn);
- B.Insert(New);
- return New;
- }
- return 0;
- }
-};
-
-struct SPrintFOpt : public LibCallOptimization {
- Value *OptimizeFixedFormatString(Function *Callee, CallInst *CI,
- IRBuilder<> &B) {
- // Check for a fixed format string.
- StringRef FormatStr;
- if (!getConstantStringInfo(CI->getArgOperand(1), FormatStr))
- return 0;
-
- // 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.
- for (unsigned i = 0, e = FormatStr.size(); i != e; ++i)
- if (FormatStr[i] == '%')
- return 0; // we found a format specifier, bail out.
-
- // These optimizations require DataLayout.
- if (!TD) return 0;
-
- // sprintf(str, fmt) -> llvm.memcpy(str, fmt, strlen(fmt)+1, 1)
- B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(1),
- ConstantInt::get(TD->getIntPtrType(*Context), // Copy the
- FormatStr.size() + 1), 1); // nul byte.
- return ConstantInt::get(CI->getType(), FormatStr.size());
- }
+ if (CI->use_empty() || !Res)
+ return Res;
+ return B.CreateIntCast(Res, CI->getType(), true);
+ }
- // 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 0;
-
- // 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 0;
- Value *V = B.CreateTrunc(CI->getArgOperand(2), B.getInt8Ty(), "char");
- Value *Ptr = CastToCStr(CI->getArgOperand(0), B);
- B.CreateStore(V, Ptr);
- Ptr = B.CreateGEP(Ptr, B.getInt32(1), "nul");
- B.CreateStore(B.getInt8(0), Ptr);
-
- return ConstantInt::get(CI->getType(), 1);
- }
+ // 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;
+}
- if (FormatStr[1] == 's') {
- // These optimizations require DataLayout.
- if (!TD) return 0;
+Value *LibCallSimplifier::optimizePrintF(CallInst *CI, IRBuilder<> &B) {
- // sprintf(dest, "%s", str) -> llvm.memcpy(dest, str, strlen(str)+1, 1)
- if (!CI->getArgOperand(2)->getType()->isPointerTy()) return 0;
+ Function *Callee = CI->getCalledFunction();
+ // Require one fixed pointer argument and an integer/void result.
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() < 1 || !FT->getParamType(0)->isPointerTy() ||
+ !(FT->getReturnType()->isIntegerTy() || FT->getReturnType()->isVoidTy()))
+ return nullptr;
+
+ if (Value *V = optimizePrintFString(CI, B)) {
+ return V;
+ }
- Value *Len = EmitStrLen(CI->getArgOperand(2), B, TD, TLI);
- if (!Len)
- return 0;
- Value *IncLen = B.CreateAdd(Len,
- ConstantInt::get(Len->getType(), 1),
- "leninc");
- B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(2), IncLen, 1);
+ // printf(format, ...) -> iprintf(format, ...) if no floating point
+ // arguments.
+ if (TLI->has(LibFunc::iprintf) && !callHasFloatingPointArgument(CI)) {
+ Module *M = B.GetInsertBlock()->getParent()->getParent();
+ Constant *IPrintFFn =
+ M->getOrInsertFunction("iprintf", FT, Callee->getAttributes());
+ CallInst *New = cast<CallInst>(CI->clone());
+ New->setCalledFunction(IPrintFFn);
+ B.Insert(New);
+ return New;
+ }
+ return nullptr;
+}
- // The sprintf result is the unincremented number of bytes in the string.
- return B.CreateIntCast(Len, CI->getType(), false);
- }
- return 0;
+Value *LibCallSimplifier::optimizeSPrintFString(CallInst *CI, IRBuilder<> &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.
+ for (unsigned i = 0, e = FormatStr.size(); i != e; ++i)
+ if (FormatStr[i] == '%')
+ return nullptr; // we found a format specifier, bail out.
+
+ // sprintf(str, fmt) -> llvm.memcpy(str, fmt, strlen(fmt)+1, 1)
+ B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(1),
+ ConstantInt::get(DL.getIntPtrType(CI->getContext()),
+ FormatStr.size() + 1),
+ 1); // Copy the null byte.
+ return ConstantInt::get(CI->getType(), FormatStr.size());
}
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- // Require two fixed pointer arguments and an integer result.
- FunctionType *FT = Callee->getFunctionType();
- if (FT->getNumParams() != 2 || !FT->getParamType(0)->isPointerTy() ||
- !FT->getParamType(1)->isPointerTy() ||
- !FT->getReturnType()->isIntegerTy())
- return 0;
+ // 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 (Value *V = OptimizeFixedFormatString(Callee, CI, B)) {
- return V;
- }
+ if (FormatStr[1] == 's') {
+ // sprintf(dest, "%s", str) -> llvm.memcpy(dest, str, strlen(str)+1, 1)
+ if (!CI->getArgOperand(2)->getType()->isPointerTy())
+ return nullptr;
- // sprintf(str, format, ...) -> siprintf(str, format, ...) if no floating
- // point arguments.
- if (TLI->has(LibFunc::siprintf) && !callHasFloatingPointArgument(CI)) {
- Module *M = B.GetInsertBlock()->getParent()->getParent();
- Constant *SIPrintFFn =
+ 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), CI->getArgOperand(2), IncLen, 1);
+
+ // 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, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
+ // Require two fixed pointer arguments and an integer result.
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 2 || !FT->getParamType(0)->isPointerTy() ||
+ !FT->getParamType(1)->isPointerTy() ||
+ !FT->getReturnType()->isIntegerTy())
+ return nullptr;
+
+ 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();
+ Constant *SIPrintFFn =
M->getOrInsertFunction("siprintf", FT, Callee->getAttributes());
- CallInst *New = cast<CallInst>(CI->clone());
- New->setCalledFunction(SIPrintFFn);
- B.Insert(New);
- return New;
- }
- return 0;
- }
-};
-
-struct FPrintFOpt : public LibCallOptimization {
- Value *optimizeFixedFormatString(Function *Callee, CallInst *CI,
- IRBuilder<> &B) {
- // All the optimizations depend on the format string.
- StringRef FormatStr;
- if (!getConstantStringInfo(CI->getArgOperand(1), FormatStr))
- return 0;
-
- // 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 0;
-
- // fprintf(F, "foo") --> fwrite("foo", 3, 1, F)
- if (CI->getNumArgOperands() == 2) {
- for (unsigned i = 0, e = FormatStr.size(); i != e; ++i)
- if (FormatStr[i] == '%') // Could handle %% -> % if we cared.
- return 0; // We found a format specifier.
-
- // These optimizations require DataLayout.
- if (!TD) return 0;
-
- return EmitFWrite(CI->getArgOperand(1),
- ConstantInt::get(TD->getIntPtrType(*Context),
- FormatStr.size()),
- CI->getArgOperand(0), B, TD, TLI);
- }
+ CallInst *New = cast<CallInst>(CI->clone());
+ New->setCalledFunction(SIPrintFFn);
+ B.Insert(New);
+ return New;
+ }
+ return nullptr;
+}
- // 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 0;
-
- // 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 0;
- return EmitFPutC(CI->getArgOperand(2), CI->getArgOperand(0), B, TD, TLI);
- }
+Value *LibCallSimplifier::optimizeFPrintFString(CallInst *CI, IRBuilder<> &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) {
+ for (unsigned i = 0, e = FormatStr.size(); i != e; ++i)
+ if (FormatStr[i] == '%') // Could handle %% -> % if we cared.
+ 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);
+ }
- if (FormatStr[1] == 's') {
- // fprintf(F, "%s", str) --> fputs(str, F)
- if (!CI->getArgOperand(2)->getType()->isPointerTy())
- return 0;
- return EmitFPutS(CI->getArgOperand(2), CI->getArgOperand(0), B, TD, TLI);
- }
- return 0;
+ // 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);
}
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- // Require two fixed paramters as pointers and integer result.
- FunctionType *FT = Callee->getFunctionType();
- if (FT->getNumParams() != 2 || !FT->getParamType(0)->isPointerTy() ||
- !FT->getParamType(1)->isPointerTy() ||
- !FT->getReturnType()->isIntegerTy())
- return 0;
+ 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;
+}
- if (Value *V = optimizeFixedFormatString(Callee, CI, B)) {
- return V;
- }
+Value *LibCallSimplifier::optimizeFPrintF(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
+ // Require two fixed paramters as pointers and integer result.
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 2 || !FT->getParamType(0)->isPointerTy() ||
+ !FT->getParamType(1)->isPointerTy() ||
+ !FT->getReturnType()->isIntegerTy())
+ return nullptr;
+
+ 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();
- Constant *FIPrintFFn =
+ // fprintf(stream, format, ...) -> fiprintf(stream, format, ...) if no
+ // floating point arguments.
+ if (TLI->has(LibFunc::fiprintf) && !callHasFloatingPointArgument(CI)) {
+ Module *M = B.GetInsertBlock()->getParent()->getParent();
+ Constant *FIPrintFFn =
M->getOrInsertFunction("fiprintf", FT, Callee->getAttributes());
- CallInst *New = cast<CallInst>(CI->clone());
- New->setCalledFunction(FIPrintFFn);
- B.Insert(New);
- return New;
- }
- return 0;
- }
-};
-
-struct FWriteOpt : public LibCallOptimization {
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- // Require a pointer, an integer, an integer, a pointer, returning integer.
- FunctionType *FT = Callee->getFunctionType();
- if (FT->getNumParams() != 4 || !FT->getParamType(0)->isPointerTy() ||
- !FT->getParamType(1)->isIntegerTy() ||
- !FT->getParamType(2)->isIntegerTy() ||
- !FT->getParamType(3)->isPointerTy() ||
- !FT->getReturnType()->isIntegerTy())
- return 0;
-
- // 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) return 0;
- 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(CastToCStr(CI->getArgOperand(0), B), "char");
- Value *NewCI = EmitFPutC(Char, CI->getArgOperand(3), B, TD, TLI);
- return NewCI ? ConstantInt::get(CI->getType(), 1) : 0;
- }
+ CallInst *New = cast<CallInst>(CI->clone());
+ New->setCalledFunction(FIPrintFFn);
+ B.Insert(New);
+ return New;
+ }
+ return nullptr;
+}
- return 0;
- }
-};
-
-struct FPutsOpt : public LibCallOptimization {
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- // These optimizations require DataLayout.
- if (!TD) return 0;
-
- // Require two pointers. Also, we can't optimize if return value is used.
- FunctionType *FT = Callee->getFunctionType();
- if (FT->getNumParams() != 2 || !FT->getParamType(0)->isPointerTy() ||
- !FT->getParamType(1)->isPointerTy() ||
- !CI->use_empty())
- return 0;
-
- // fputs(s,F) --> fwrite(s,1,strlen(s),F)
- uint64_t Len = GetStringLength(CI->getArgOperand(0));
- if (!Len) return 0;
- // Known to have no uses (see above).
- return EmitFWrite(CI->getArgOperand(0),
- ConstantInt::get(TD->getIntPtrType(*Context), Len-1),
- CI->getArgOperand(1), B, TD, TLI);
- }
-};
-
-struct PutsOpt : public LibCallOptimization {
- virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- // Require one fixed pointer argument and an integer/void result.
- FunctionType *FT = Callee->getFunctionType();
- if (FT->getNumParams() < 1 || !FT->getParamType(0)->isPointerTy() ||
- !(FT->getReturnType()->isIntegerTy() ||
- FT->getReturnType()->isVoidTy()))
- return 0;
-
- // Check for a constant string.
- StringRef Str;
- if (!getConstantStringInfo(CI->getArgOperand(0), Str))
- return 0;
-
- if (Str.empty() && CI->use_empty()) {
- // puts("") -> putchar('\n')
- Value *Res = EmitPutChar(B.getInt32('\n'), B, TD, TLI);
- if (CI->use_empty() || !Res) return Res;
- return B.CreateIntCast(Res, CI->getType(), true);
- }
+Value *LibCallSimplifier::optimizeFWrite(CallInst *CI, IRBuilder<> &B) {
+ optimizeErrorReporting(CI, B, 3);
- return 0;
+ Function *Callee = CI->getCalledFunction();
+ // Require a pointer, an integer, an integer, a pointer, returning integer.
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 4 || !FT->getParamType(0)->isPointerTy() ||
+ !FT->getParamType(1)->isIntegerTy() ||
+ !FT->getParamType(2)->isIntegerTy() ||
+ !FT->getParamType(3)->isPointerTy() ||
+ !FT->getReturnType()->isIntegerTy())
+ return nullptr;
+
+ // 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)
+ return nullptr;
+ 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(CastToCStr(CI->getArgOperand(0), B), "char");
+ Value *NewCI = EmitFPutC(Char, CI->getArgOperand(3), B, TLI);
+ return NewCI ? ConstantInt::get(CI->getType(), 1) : nullptr;
}
-};
-} // End anonymous namespace.
+ return nullptr;
+}
+
+Value *LibCallSimplifier::optimizeFPuts(CallInst *CI, IRBuilder<> &B) {
+ optimizeErrorReporting(CI, B, 1);
-namespace llvm {
+ Function *Callee = CI->getCalledFunction();
-class LibCallSimplifierImpl {
- const DataLayout *TD;
- const TargetLibraryInfo *TLI;
- const LibCallSimplifier *LCS;
- bool UnsafeFPShrink;
+ // Require two pointers. Also, we can't optimize if return value is used.
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 2 || !FT->getParamType(0)->isPointerTy() ||
+ !FT->getParamType(1)->isPointerTy() || !CI->use_empty())
+ return nullptr;
+
+ // fputs(s,F) --> fwrite(s,1,strlen(s),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);
+}
- // Math library call optimizations.
- CosOpt Cos;
- PowOpt Pow;
- Exp2Opt Exp2;
-public:
- LibCallSimplifierImpl(const DataLayout *TD, const TargetLibraryInfo *TLI,
- const LibCallSimplifier *LCS,
- bool UnsafeFPShrink = false)
- : Cos(UnsafeFPShrink), Pow(UnsafeFPShrink), Exp2(UnsafeFPShrink) {
- this->TD = TD;
- this->TLI = TLI;
- this->LCS = LCS;
- this->UnsafeFPShrink = UnsafeFPShrink;
+Value *LibCallSimplifier::optimizePuts(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
+ // Require one fixed pointer argument and an integer/void result.
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() < 1 || !FT->getParamType(0)->isPointerTy() ||
+ !(FT->getReturnType()->isIntegerTy() || FT->getReturnType()->isVoidTy()))
+ return nullptr;
+
+ // Check for a constant string.
+ StringRef Str;
+ if (!getConstantStringInfo(CI->getArgOperand(0), Str))
+ return nullptr;
+
+ if (Str.empty() && CI->use_empty()) {
+ // puts("") -> putchar('\n')
+ Value *Res = EmitPutChar(B.getInt32('\n'), B, TLI);
+ if (CI->use_empty() || !Res)
+ return Res;
+ return B.CreateIntCast(Res, CI->getType(), true);
}
- Value *optimizeCall(CallInst *CI);
- LibCallOptimization *lookupOptimization(CallInst *CI);
- bool hasFloatVersion(StringRef FuncName);
-};
+ return nullptr;
+}
-bool LibCallSimplifierImpl::hasFloatVersion(StringRef FuncName) {
+bool LibCallSimplifier::hasFloatVersion(StringRef FuncName) {
LibFunc::Func Func;
SmallString<20> FloatFuncName = FuncName;
FloatFuncName += 'f';
return false;
}
-// Fortified library call optimizations.
-static MemCpyChkOpt MemCpyChk;
-static MemMoveChkOpt MemMoveChk;
-static MemSetChkOpt MemSetChk;
-static StrCpyChkOpt StrCpyChk;
-static StpCpyChkOpt StpCpyChk;
-static StrNCpyChkOpt StrNCpyChk;
-
-// String library call optimizations.
-static StrCatOpt StrCat;
-static StrNCatOpt StrNCat;
-static StrChrOpt StrChr;
-static StrRChrOpt StrRChr;
-static StrCmpOpt StrCmp;
-static StrNCmpOpt StrNCmp;
-static StrCpyOpt StrCpy;
-static StpCpyOpt StpCpy;
-static StrNCpyOpt StrNCpy;
-static StrLenOpt StrLen;
-static StrPBrkOpt StrPBrk;
-static StrToOpt StrTo;
-static StrSpnOpt StrSpn;
-static StrCSpnOpt StrCSpn;
-static StrStrOpt StrStr;
-
-// Memory library call optimizations.
-static MemCmpOpt MemCmp;
-static MemCpyOpt MemCpy;
-static MemMoveOpt MemMove;
-static MemSetOpt MemSet;
-
-// Math library call optimizations.
-static UnaryDoubleFPOpt UnaryDoubleFP(false);
-static UnaryDoubleFPOpt UnsafeUnaryDoubleFP(true);
-
- // Integer library call optimizations.
-static FFSOpt FFS;
-static AbsOpt Abs;
-static IsDigitOpt IsDigit;
-static IsAsciiOpt IsAscii;
-static ToAsciiOpt ToAscii;
-
-// Formatting and IO library call optimizations.
-static PrintFOpt PrintF;
-static SPrintFOpt SPrintF;
-static FPrintFOpt FPrintF;
-static FWriteOpt FWrite;
-static FPutsOpt FPuts;
-static PutsOpt Puts;
-
-LibCallOptimization *LibCallSimplifierImpl::lookupOptimization(CallInst *CI) {
+Value *LibCallSimplifier::optimizeStringMemoryLibCall(CallInst *CI,
+ IRBuilder<> &Builder) {
LibFunc::Func Func;
Function *Callee = CI->getCalledFunction();
StringRef FuncName = Callee->getName();
- // Next check for intrinsics.
+ // Check for string/memory library functions.
+ if (TLI->getLibFunc(FuncName, Func) && TLI->has(Func)) {
+ // Make sure we never change the calling convention.
+ assert((ignoreCallingConv(Func) ||
+ CI->getCallingConv() == llvm::CallingConv::C) &&
+ "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::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::memcmp:
+ return optimizeMemCmp(CI, Builder);
+ case LibFunc::memcpy:
+ return optimizeMemCpy(CI, Builder);
+ case LibFunc::memmove:
+ return optimizeMemMove(CI, Builder);
+ case LibFunc::memset:
+ return optimizeMemSet(CI, Builder);
+ default:
+ break;
+ }
+ }
+ return nullptr;
+}
+
+Value *LibCallSimplifier::optimizeCall(CallInst *CI) {
+ if (CI->isNoBuiltin())
+ return nullptr;
+
+ LibFunc::Func Func;
+ Function *Callee = CI->getCalledFunction();
+ StringRef FuncName = Callee->getName();
+ IRBuilder<> Builder(CI);
+ bool isCallingConvC = CI->getCallingConv() == llvm::CallingConv::C;
+
+ // Command-line parameter overrides function attribute.
+ if (EnableUnsafeFPShrink.getNumOccurrences() > 0)
+ UnsafeFPShrink = EnableUnsafeFPShrink;
+ else if (canUseUnsafeFPMath(Callee))
+ UnsafeFPShrink = true;
+
+ // First, check for intrinsics.
if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(CI)) {
+ if (!isCallingConvC)
+ return nullptr;
switch (II->getIntrinsicID()) {
case Intrinsic::pow:
- return &Pow;
+ return optimizePow(CI, Builder);
case Intrinsic::exp2:
- return &Exp2;
+ return optimizeExp2(CI, Builder);
+ case Intrinsic::fabs:
+ return optimizeFabs(CI, Builder);
+ case Intrinsic::sqrt:
+ return optimizeSqrt(CI, Builder);
default:
- return 0;
+ return nullptr;
}
}
- // Then check for known library functions.
- if (TLI->getLibFunc(FuncName, Func) && TLI->has(Func)) {
- switch (Func) {
- case LibFunc::strcat:
- return &StrCat;
- case LibFunc::strncat:
- return &StrNCat;
- case LibFunc::strchr:
- return &StrChr;
- case LibFunc::strrchr:
- return &StrRChr;
- case LibFunc::strcmp:
- return &StrCmp;
- case LibFunc::strncmp:
- return &StrNCmp;
- case LibFunc::strcpy:
- return &StrCpy;
- case LibFunc::stpcpy:
- return &StpCpy;
- case LibFunc::strncpy:
- return &StrNCpy;
- case LibFunc::strlen:
- return &StrLen;
- case LibFunc::strpbrk:
- return &StrPBrk;
- case LibFunc::strtol:
- case LibFunc::strtod:
- case LibFunc::strtof:
- case LibFunc::strtoul:
- case LibFunc::strtoll:
- case LibFunc::strtold:
- case LibFunc::strtoull:
- return &StrTo;
- case LibFunc::strspn:
- return &StrSpn;
- case LibFunc::strcspn:
- return &StrCSpn;
- case LibFunc::strstr:
- return &StrStr;
- case LibFunc::memcmp:
- return &MemCmp;
- case LibFunc::memcpy:
- return &MemCpy;
- case LibFunc::memmove:
- return &MemMove;
- case LibFunc::memset:
- return &MemSet;
- case LibFunc::cosf:
- case LibFunc::cos:
- case LibFunc::cosl:
- return &Cos;
- case LibFunc::powf:
- case LibFunc::pow:
- case LibFunc::powl:
- return &Pow;
- case LibFunc::exp2l:
- case LibFunc::exp2:
- case LibFunc::exp2f:
- return &Exp2;
- case LibFunc::ffs:
- case LibFunc::ffsl:
- case LibFunc::ffsll:
- return &FFS;
- case LibFunc::abs:
- case LibFunc::labs:
- case LibFunc::llabs:
- return &Abs;
- case LibFunc::isdigit:
- return &IsDigit;
- case LibFunc::isascii:
- return &IsAscii;
- case LibFunc::toascii:
- return &ToAscii;
- case LibFunc::printf:
- return &PrintF;
- case LibFunc::sprintf:
- return &SPrintF;
- case LibFunc::fprintf:
- return &FPrintF;
- case LibFunc::fwrite:
- return &FWrite;
- case LibFunc::fputs:
- return &FPuts;
- case LibFunc::puts:
- return &Puts;
- case LibFunc::ceil:
- case LibFunc::fabs:
- case LibFunc::floor:
- case LibFunc::rint:
- case LibFunc::round:
- case LibFunc::nearbyint:
- case LibFunc::trunc:
- if (hasFloatVersion(FuncName))
- return &UnaryDoubleFP;
- return 0;
- 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::log:
- case LibFunc::log10:
- case LibFunc::log1p:
- case LibFunc::log2:
- case LibFunc::logb:
- case LibFunc::sin:
- case LibFunc::sinh:
- case LibFunc::sqrt:
- case LibFunc::tan:
- case LibFunc::tanh:
- if (UnsafeFPShrink && hasFloatVersion(FuncName))
- return &UnsafeUnaryDoubleFP;
- return 0;
- case LibFunc::memcpy_chk:
- return &MemCpyChk;
- default:
- return 0;
+ // Also try to simplify calls to fortified library functions.
+ if (Value *SimplifiedFortifiedCI = FortifiedSimplifier.optimizeCall(CI)) {
+ // Try to further simplify the result.
+ CallInst *SimplifiedCI = dyn_cast<CallInst>(SimplifiedFortifiedCI);
+ if (SimplifiedCI && SimplifiedCI->getCalledFunction()) {
+ // Use an IR Builder from SimplifiedCI if available instead of CI
+ // to guarantee we reach all uses we might replace later on.
+ IRBuilder<> TmpBuilder(SimplifiedCI);
+ if (Value *V = optimizeStringMemoryLibCall(SimplifiedCI, TmpBuilder)) {
+ // If we were able to further simplify, remove the now redundant call.
+ SimplifiedCI->replaceAllUsesWith(V);
+ SimplifiedCI->eraseFromParent();
+ return V;
}
+ }
+ return SimplifiedFortifiedCI;
}
- // Finally check for fortified library calls.
- if (FuncName.endswith("_chk")) {
- if (FuncName == "__memmove_chk")
- return &MemMoveChk;
- else if (FuncName == "__memset_chk")
- return &MemSetChk;
- else if (FuncName == "__strcpy_chk")
- return &StrCpyChk;
- else if (FuncName == "__stpcpy_chk")
- return &StpCpyChk;
- else if (FuncName == "__strncpy_chk")
- return &StrNCpyChk;
- else if (FuncName == "__stpncpy_chk")
- return &StrNCpyChk;
- }
-
- return 0;
-
-}
-
-Value *LibCallSimplifierImpl::optimizeCall(CallInst *CI) {
- LibCallOptimization *LCO = lookupOptimization(CI);
- if (LCO) {
- IRBuilder<> Builder(CI);
- return LCO->optimizeCall(CI, TD, TLI, LCS, Builder);
+ // Then check for known library functions.
+ if (TLI->getLibFunc(FuncName, Func) && TLI->has(Func)) {
+ // We never change the calling convention.
+ if (!ignoreCallingConv(Func) && !isCallingConvC)
+ return nullptr;
+ if (Value *V = optimizeStringMemoryLibCall(CI, Builder))
+ return V;
+ switch (Func) {
+ case LibFunc::cosf:
+ case LibFunc::cos:
+ case LibFunc::cosl:
+ return optimizeCos(CI, Builder);
+ 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 optimizeFabs(CI, Builder);
+ case LibFunc::sqrtf:
+ case LibFunc::sqrt:
+ case LibFunc::sqrtl:
+ return optimizeSqrt(CI, Builder);
+ case LibFunc::ffs:
+ case LibFunc::ffsl:
+ case LibFunc::ffsll:
+ return optimizeFFS(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::printf:
+ return optimizePrintF(CI, Builder);
+ case LibFunc::sprintf:
+ return optimizeSPrintF(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::tan:
+ case LibFunc::tanf:
+ case LibFunc::tanl:
+ return optimizeTan(CI, Builder);
+ case LibFunc::perror:
+ return optimizeErrorReporting(CI, Builder);
+ case LibFunc::vfprintf:
+ case LibFunc::fiprintf:
+ return optimizeErrorReporting(CI, Builder, 0);
+ case LibFunc::fputc:
+ return optimizeErrorReporting(CI, Builder, 1);
+ case LibFunc::ceil:
+ case LibFunc::floor:
+ case LibFunc::rint:
+ case LibFunc::round:
+ case LibFunc::nearbyint:
+ case LibFunc::trunc:
+ if (hasFloatVersion(FuncName))
+ return optimizeUnaryDoubleFP(CI, Builder, false);
+ return nullptr;
+ 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::log:
+ case LibFunc::log10:
+ case LibFunc::log1p:
+ case LibFunc::log2:
+ case LibFunc::logb:
+ case LibFunc::sin:
+ case LibFunc::sinh:
+ case LibFunc::tanh:
+ if (UnsafeFPShrink && hasFloatVersion(FuncName))
+ return optimizeUnaryDoubleFP(CI, Builder, true);
+ return nullptr;
+ case LibFunc::copysign:
+ if (hasFloatVersion(FuncName))
+ 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);
+ default:
+ return nullptr;
+ }
}
- return 0;
+ return nullptr;
}
-LibCallSimplifier::LibCallSimplifier(const DataLayout *TD,
- const TargetLibraryInfo *TLI,
- bool UnsafeFPShrink) {
- Impl = new LibCallSimplifierImpl(TD, TLI, this, UnsafeFPShrink);
-}
-
-LibCallSimplifier::~LibCallSimplifier() {
- delete Impl;
-}
-
-Value *LibCallSimplifier::optimizeCall(CallInst *CI) {
- if (CI->hasFnAttr(Attribute::NoBuiltin)) return 0;
- return Impl->optimizeCall(CI);
-}
-
-void LibCallSimplifier::replaceAllUsesWith(Instruction *I, Value *With) const {
- I->replaceAllUsesWith(With);
- I->eraseFromParent();
-}
+LibCallSimplifier::LibCallSimplifier(
+ const DataLayout &DL, const TargetLibraryInfo *TLI,
+ function_ref<void(Instruction *, Value *)> Replacer)
+ : FortifiedSimplifier(TLI), DL(DL), TLI(TLI), UnsafeFPShrink(false),
+ Replacer(Replacer) {}
+void LibCallSimplifier::replaceAllUsesWith(Instruction *I, Value *With) {
+ // Indirect through the replacer used in this instance.
+ Replacer(I, With);
}
// TODO:
// cbrt:
// * cbrt(expN(X)) -> expN(x/3)
// * cbrt(sqrt(x)) -> pow(x,1/6)
-// * cbrt(sqrt(x)) -> pow(x,1/9)
+// * cbrt(cbrt(x)) -> pow(x,1/9)
//
// exp, expf, expl:
// * exp(log(x)) -> x
// * sqrt(Nroot(x)) -> pow(x,1/(2*N))
// * sqrt(pow(x,y)) -> pow(|x|,y*0.5)
//
-// strchr:
-// * strchr(p, 0) -> strlen(p)
// tan, tanf, tanl:
// * tan(atan(x)) -> x
//
// * trunc(cnst) -> cnst'
//
//
+
+//===----------------------------------------------------------------------===//
+// Fortified Library Call Optimizations
+//===----------------------------------------------------------------------===//
+
+bool FortifiedLibCallSimplifier::isFortifiedCallFoldable(CallInst *CI,
+ unsigned ObjSizeOp,
+ unsigned SizeOp,
+ bool isString) {
+ if (CI->getArgOperand(ObjSizeOp) == CI->getArgOperand(SizeOp))
+ return true;
+ if (ConstantInt *ObjSizeCI =
+ dyn_cast<ConstantInt>(CI->getArgOperand(ObjSizeOp))) {
+ if (ObjSizeCI->isAllOnesValue())
+ return true;
+ // If the object size wasn't -1 (unknown), bail out if we were asked to.
+ if (OnlyLowerUnknownSize)
+ return false;
+ if (isString) {
+ uint64_t Len = GetStringLength(CI->getArgOperand(SizeOp));
+ // If the length is 0 we don't know how long it is and so we can't
+ // remove the check.
+ if (Len == 0)
+ return false;
+ return ObjSizeCI->getZExtValue() >= Len;
+ }
+ if (ConstantInt *SizeCI = dyn_cast<ConstantInt>(CI->getArgOperand(SizeOp)))
+ return ObjSizeCI->getZExtValue() >= SizeCI->getZExtValue();
+ }
+ return false;
+}
+
+Value *FortifiedLibCallSimplifier::optimizeMemCpyChk(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
+
+ if (!checkStringCopyLibFuncSignature(Callee, LibFunc::memcpy_chk))
+ return nullptr;
+
+ if (isFortifiedCallFoldable(CI, 3, 2, false)) {
+ B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(1),
+ CI->getArgOperand(2), 1);
+ return CI->getArgOperand(0);
+ }
+ return nullptr;
+}
+
+Value *FortifiedLibCallSimplifier::optimizeMemMoveChk(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
+
+ if (!checkStringCopyLibFuncSignature(Callee, LibFunc::memmove_chk))
+ return nullptr;
+
+ if (isFortifiedCallFoldable(CI, 3, 2, false)) {
+ B.CreateMemMove(CI->getArgOperand(0), CI->getArgOperand(1),
+ CI->getArgOperand(2), 1);
+ return CI->getArgOperand(0);
+ }
+ return nullptr;
+}
+
+Value *FortifiedLibCallSimplifier::optimizeMemSetChk(CallInst *CI, IRBuilder<> &B) {
+ Function *Callee = CI->getCalledFunction();
+
+ if (!checkStringCopyLibFuncSignature(Callee, LibFunc::memset_chk))
+ return nullptr;
+
+ if (isFortifiedCallFoldable(CI, 3, 2, false)) {
+ Value *Val = B.CreateIntCast(CI->getArgOperand(1), B.getInt8Ty(), false);
+ B.CreateMemSet(CI->getArgOperand(0), Val, CI->getArgOperand(2), 1);
+ return CI->getArgOperand(0);
+ }
+ return nullptr;
+}
+
+Value *FortifiedLibCallSimplifier::optimizeStrpCpyChk(CallInst *CI,
+ IRBuilder<> &B,
+ LibFunc::Func Func) {
+ Function *Callee = CI->getCalledFunction();
+ StringRef Name = Callee->getName();
+ const DataLayout &DL = CI->getModule()->getDataLayout();
+
+ if (!checkStringCopyLibFuncSignature(Callee, Func))
+ return nullptr;
+
+ 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, 1, true))
+ return EmitStrCpy(Dst, Src, B, TLI, Name.substr(2, 6));
+
+ if (OnlyLowerUnknownSize)
+ return nullptr;
+
+ // Maybe we can stil fold __st[rp]cpy_chk to __memcpy_chk.
+ uint64_t Len = GetStringLength(Src);
+ if (Len == 0)
+ 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::optimizeStrpNCpyChk(CallInst *CI,
+ IRBuilder<> &B,
+ LibFunc::Func Func) {
+ Function *Callee = CI->getCalledFunction();
+ StringRef Name = Callee->getName();
+
+ if (!checkStringCopyLibFuncSignature(Callee, Func))
+ return nullptr;
+ if (isFortifiedCallFoldable(CI, 3, 2, false)) {
+ Value *Ret = EmitStrNCpy(CI->getArgOperand(0), CI->getArgOperand(1),
+ CI->getArgOperand(2), B, TLI, Name.substr(2, 7));
+ return Ret;
+ }
+ return nullptr;
+}
+
+Value *FortifiedLibCallSimplifier::optimizeCall(CallInst *CI) {
+ // 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 Func;
+ Function *Callee = CI->getCalledFunction();
+ StringRef FuncName = Callee->getName();
+ IRBuilder<> Builder(CI);
+ bool isCallingConvC = CI->getCallingConv() == llvm::CallingConv::C;
+
+ // First, check that this is a known library functions.
+ if (!TLI->getLibFunc(FuncName, 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::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::stpncpy_chk:
+ case LibFunc::strncpy_chk:
+ return optimizeStrpNCpyChk(CI, Builder, Func);
+ default:
+ break;
+ }
+ return nullptr;
+}
+
+FortifiedLibCallSimplifier::FortifiedLibCallSimplifier(
+ const TargetLibraryInfo *TLI, bool OnlyLowerUnknownSize)
+ : TLI(TLI), OnlyLowerUnknownSize(OnlyLowerUnknownSize) {}
projects / oota-llvm.git / blobdiff