diff options
Diffstat (limited to 'contrib/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp')
-rw-r--r-- | contrib/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp | 988 |
1 files changed, 894 insertions, 94 deletions
diff --git a/contrib/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp b/contrib/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp index c3ea638..c231704 100644 --- a/contrib/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp +++ b/contrib/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp @@ -15,12 +15,17 @@ //===----------------------------------------------------------------------===// #include "llvm/Transforms/Utils/SimplifyLibCalls.h" -#include "llvm/DataLayout.h" +#include "llvm/ADT/SmallString.h" #include "llvm/ADT/StringMap.h" #include "llvm/Analysis/ValueTracking.h" -#include "llvm/Function.h" -#include "llvm/IRBuilder.h" -#include "llvm/LLVMContext.h" +#include "llvm/IR/DataLayout.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/Support/Allocator.h" #include "llvm/Target/TargetLibraryInfo.h" #include "llvm/Transforms/Utils/BuildLibCalls.h" @@ -48,6 +53,10 @@ public: 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) { @@ -59,7 +68,7 @@ public: Context = &CI->getCalledFunction()->getContext(); // We never change the calling convention. - if (CI->getCallingConv() != llvm::CallingConv::C) + if (!ignoreCallingConv() && CI->getCallingConv() != llvm::CallingConv::C) return NULL; return callOptimizer(CI->getCalledFunction(), CI, B); @@ -100,6 +109,15 @@ static bool isOnlyUsedInEqualityComparison(Value *V, Value *With) { return true; } +static bool callHasFloatingPointArgument(const CallInst *CI) { + for (CallInst::const_op_iterator it = CI->op_begin(), e = CI->op_end(); + it != e; ++it) { + if ((*it)->getType()->isFloatingPointTy()) + return true; + } + return false; +} + //===----------------------------------------------------------------------===// // Fortified Library Call Optimizations //===----------------------------------------------------------------------===// @@ -713,6 +731,7 @@ struct StrNCpyOpt : public LibCallOptimization { }; 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 || @@ -781,8 +800,7 @@ struct StrToOpt : public LibCallOptimization { 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, Attributes::get(Callee->getContext(), - Attributes::NoCapture)); + CI->addAttribute(1, Attribute::NoCapture); } return 0; @@ -951,7 +969,14 @@ struct MemCmpOpt : public LibCallOptimization { // Make sure we're not reading out-of-bounds memory. if (Len > LHSStr.size() || Len > RHSStr.size()) return 0; - uint64_t Ret = memcmp(LHSStr.data(), RHSStr.data(), Len); + // 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); } @@ -1016,6 +1041,630 @@ struct MemSetOpt : public LibCallOptimization { } }; +//===----------------------------------------------------------------------===// +// Math Library Optimizations +//===----------------------------------------------------------------------===// + +//===----------------------------------------------------------------------===// +// 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; + } + } + + // 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; + } +}; + +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); + } + + 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); + } + + 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)) { + 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()); + } + + 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; + } + + 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); + } + + 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 + Value *LdExpArg = 0; + if (SIToFPInst *OpC = dyn_cast<SIToFPInst>(Op)) { + if (OpC->getOperand(0)->getType()->getPrimitiveSizeInBits() <= 32) + LdExpArg = B.CreateSExt(OpC->getOperand(0), B.getInt32Ty()); + } else if (UIToFPInst *OpC = dyn_cast<UIToFPInst>(Op)) { + if (OpC->getOperand(0)->getType()->getPrimitiveSizeInBits() < 32) + LdExpArg = B.CreateZExt(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)); + 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); + if (const Function *F = dyn_cast<Function>(Callee->stripPointerCasts())) + CI->setCallingConv(F->getCallingConv()); + + return CI; + } + return Ret; + } +}; + +//===----------------------------------------------------------------------===// +// 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); + } + + // 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)); + } +}; + +//===----------------------------------------------------------------------===// +// 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); + } + + // 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); + } + + // 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); + + if (CI->use_empty() || !Res) return Res; + return B.CreateIntCast(Res, CI->getType(), true); + } + + // 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; + } + + 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; + + if (Value *V = optimizeFixedFormatString(Callee, CI, B)) { + return V; + } + + // printf(format, ...) -> iprintf(format, ...) if no floating point + // arguments. + if (TLI->has(LibFunc::iprintf) && !callHasFloatingPointArgument(CI)) { + Module *M = B.GetInsertBlock()->getParent()->getParent(); + 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()); + } + + // 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); + } + + if (FormatStr[1] == 's') { + // These optimizations require DataLayout. + if (!TD) return 0; + + // sprintf(dest, "%s", str) -> llvm.memcpy(dest, str, strlen(str)+1, 1) + if (!CI->getArgOperand(2)->getType()->isPointerTy()) return 0; + + 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); + + // The sprintf result is the unincremented number of bytes in the string. + return B.CreateIntCast(Len, CI->getType(), false); + } + return 0; + } + + 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; + + if (Value *V = OptimizeFixedFormatString(Callee, 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; + + // 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; + + Value *NewCI = EmitFWrite(CI->getArgOperand(1), + ConstantInt::get(TD->getIntPtrType(*Context), + FormatStr.size()), + CI->getArgOperand(0), B, TD, TLI); + return NewCI ? ConstantInt::get(CI->getType(), FormatStr.size()) : 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 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; + Value *NewCI = EmitFPutC(CI->getArgOperand(2), CI->getArgOperand(0), B, + TD, TLI); + return NewCI ? ConstantInt::get(CI->getType(), 1) : 0; + } + + if (FormatStr[1] == 's') { + // fprintf(F, "%s", str) --> fputs(str, F) + if (!CI->getArgOperand(2)->getType()->isPointerTy() || !CI->use_empty()) + return 0; + return EmitFPutS(CI->getArgOperand(2), CI->getArgOperand(0), B, TD, TLI); + } + return 0; + } + + 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 (Value *V = optimizeFixedFormatString(Callee, 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 = + 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; + } + + 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); + } + + return 0; + } +}; + } // End anonymous namespace. namespace llvm { @@ -1024,98 +1673,252 @@ class LibCallSimplifierImpl { const DataLayout *TD; const TargetLibraryInfo *TLI; const LibCallSimplifier *LCS; - StringMap<LibCallOptimization*> Optimizations; - - // Fortified library call optimizations. - MemCpyChkOpt MemCpyChk; - MemMoveChkOpt MemMoveChk; - MemSetChkOpt MemSetChk; - StrCpyChkOpt StrCpyChk; - StpCpyChkOpt StpCpyChk; - StrNCpyChkOpt StrNCpyChk; - - // String library call optimizations. - StrCatOpt StrCat; - StrNCatOpt StrNCat; - StrChrOpt StrChr; - StrRChrOpt StrRChr; - StrCmpOpt StrCmp; - StrNCmpOpt StrNCmp; - StrCpyOpt StrCpy; - StpCpyOpt StpCpy; - StrNCpyOpt StrNCpy; - StrLenOpt StrLen; - StrPBrkOpt StrPBrk; - StrToOpt StrTo; - StrSpnOpt StrSpn; - StrCSpnOpt StrCSpn; - StrStrOpt StrStr; - - // Memory library call optimizations. - MemCmpOpt MemCmp; - MemCpyOpt MemCpy; - MemMoveOpt MemMove; - MemSetOpt MemSet; - - void initOptimizations(); - void addOpt(LibFunc::Func F, LibCallOptimization* Opt); + bool UnsafeFPShrink; + + // Math library call optimizations. + CosOpt Cos; + PowOpt Pow; + Exp2Opt Exp2; public: LibCallSimplifierImpl(const DataLayout *TD, const TargetLibraryInfo *TLI, - const LibCallSimplifier *LCS) { + 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 *optimizeCall(CallInst *CI); + LibCallOptimization *lookupOptimization(CallInst *CI); + bool hasFloatVersion(StringRef FuncName); }; -void LibCallSimplifierImpl::initOptimizations() { - // Fortified library call optimizations. - Optimizations["__memcpy_chk"] = &MemCpyChk; - Optimizations["__memmove_chk"] = &MemMoveChk; - Optimizations["__memset_chk"] = &MemSetChk; - Optimizations["__strcpy_chk"] = &StrCpyChk; - Optimizations["__stpcpy_chk"] = &StpCpyChk; - Optimizations["__strncpy_chk"] = &StrNCpyChk; - Optimizations["__stpncpy_chk"] = &StrNCpyChk; - - // String library call optimizations. - addOpt(LibFunc::strcat, &StrCat); - addOpt(LibFunc::strncat, &StrNCat); - addOpt(LibFunc::strchr, &StrChr); - addOpt(LibFunc::strrchr, &StrRChr); - addOpt(LibFunc::strcmp, &StrCmp); - addOpt(LibFunc::strncmp, &StrNCmp); - addOpt(LibFunc::strcpy, &StrCpy); - addOpt(LibFunc::stpcpy, &StpCpy); - addOpt(LibFunc::strncpy, &StrNCpy); - addOpt(LibFunc::strlen, &StrLen); - addOpt(LibFunc::strpbrk, &StrPBrk); - addOpt(LibFunc::strtol, &StrTo); - addOpt(LibFunc::strtod, &StrTo); - addOpt(LibFunc::strtof, &StrTo); - addOpt(LibFunc::strtoul, &StrTo); - addOpt(LibFunc::strtoll, &StrTo); - addOpt(LibFunc::strtold, &StrTo); - addOpt(LibFunc::strtoull, &StrTo); - addOpt(LibFunc::strspn, &StrSpn); - addOpt(LibFunc::strcspn, &StrCSpn); - addOpt(LibFunc::strstr, &StrStr); - - // Memory library call optimizations. - addOpt(LibFunc::memcmp, &MemCmp); - addOpt(LibFunc::memcpy, &MemCpy); - addOpt(LibFunc::memmove, &MemMove); - addOpt(LibFunc::memset, &MemSet); +bool LibCallSimplifierImpl::hasFloatVersion(StringRef FuncName) { + LibFunc::Func Func; + SmallString<20> FloatFuncName = FuncName; + FloatFuncName += 'f'; + if (TLI->getLibFunc(FloatFuncName, Func)) + return TLI->has(Func); + return false; } -Value *LibCallSimplifierImpl::optimizeCall(CallInst *CI) { - if (Optimizations.empty()) - initOptimizations(); - +// 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) { + LibFunc::Func Func; Function *Callee = CI->getCalledFunction(); - LibCallOptimization *LCO = Optimizations.lookup(Callee->getName()); + StringRef FuncName = Callee->getName(); + + // Next check for intrinsics. + if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(CI)) { + switch (II->getIntrinsicID()) { + case Intrinsic::pow: + return &Pow; + case Intrinsic::exp2: + return &Exp2; + default: + return 0; + } + } + + // 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; + } + } + + // 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); @@ -1123,14 +1926,10 @@ Value *LibCallSimplifierImpl::optimizeCall(CallInst *CI) { return 0; } -void LibCallSimplifierImpl::addOpt(LibFunc::Func F, LibCallOptimization* Opt) { - if (TLI->has(F)) - Optimizations[TLI->getName(F)] = Opt; -} - LibCallSimplifier::LibCallSimplifier(const DataLayout *TD, - const TargetLibraryInfo *TLI) { - Impl = new LibCallSimplifierImpl(TD, TLI, this); + const TargetLibraryInfo *TLI, + bool UnsafeFPShrink) { + Impl = new LibCallSimplifierImpl(TD, TLI, this, UnsafeFPShrink); } LibCallSimplifier::~LibCallSimplifier() { @@ -1138,6 +1937,7 @@ LibCallSimplifier::~LibCallSimplifier() { } Value *LibCallSimplifier::optimizeCall(CallInst *CI) { + if (CI->hasFnAttr(Attribute::NoBuiltin)) return 0; return Impl->optimizeCall(CI); } |