maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity

Optimize memmove and memset into the LLVM builtins. Note that these 

only show up in code from front-ends besides llvm-gcc, like clang.

llvm-svn: 60287
This commit is contained in:
Eli Friedman 2008-11-30 08:32:11 +00:00
parent e9ef170d4a
commit 09bc610945
3 changed files with 81 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

61
llvm/lib/Transforms/Scalar/SimplifyLibCalls.cpp
View File

@ -707,6 +707,60 @@ struct VISIBILITY_HIDDEN MemCpyOpt : public LibCallOptimization {
}
};
//===---------------------------------------===//
// 'memmove' Optimizations
struct VISIBILITY_HIDDEN MemMoveOpt : public LibCallOptimization {
virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
const FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() != 3 || FT->getReturnType() != FT->getParamType(0) ||
!isa<PointerType>(FT->getParamType(0)) ||
!isa<PointerType>(FT->getParamType(1)) ||
FT->getParamType(2) != TD->getIntPtrType())
return 0;
// memmove(x, y, n) -> llvm.memmove(x, y, n, 1)
Module *M = Caller->getParent();
Intrinsic::ID IID = Intrinsic::memmove;
const Type *Tys[1];
Tys[0] = TD->getIntPtrType();
Value *MemMove = Intrinsic::getDeclaration(M, IID, Tys, 1);
Value *Dst = CastToCStr(CI->getOperand(1), B);
Value *Src = CastToCStr(CI->getOperand(2), B);
Value *Size = CI->getOperand(3);
Value *Align = ConstantInt::get(Type::Int32Ty, 1);
B.CreateCall4(MemMove, Dst, Src, Size, Align);
return CI->getOperand(1);
}
};
//===---------------------------------------===//
// 'memset' Optimizations
struct VISIBILITY_HIDDEN MemSetOpt : public LibCallOptimization {
virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
const FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() != 3 || FT->getReturnType() != FT->getParamType(0) ||
!isa<PointerType>(FT->getParamType(0)) ||
FT->getParamType(1) != TD->getIntPtrType() ||
FT->getParamType(2) != TD->getIntPtrType())
return 0;
// memset(p, v, n) -> llvm.memset(p, v, n, 1)
Module *M = Caller->getParent();
Intrinsic::ID IID = Intrinsic::memset;
const Type *Tys[1];
Tys[0] = TD->getIntPtrType();
Value *MemSet = Intrinsic::getDeclaration(M, IID, Tys, 1);
Value *Dst = CastToCStr(CI->getOperand(1), B);
Value *Val = B.CreateTrunc(CI->getOperand(2), Type::Int8Ty);
Value *Size = CI->getOperand(3);
Value *Align = ConstantInt::get(Type::Int32Ty, 1);
B.CreateCall4(MemSet, Dst, Val, Size, Align);
return CI->getOperand(1);
}
};
//===----------------------------------------------------------------------===//
// Math Library Optimizations
//===----------------------------------------------------------------------===//
@ -1197,6 +1251,7 @@ namespace {
// String and Memory LibCall Optimizations
StrCatOpt StrCat; StrChrOpt StrChr; StrCmpOpt StrCmp; StrNCmpOpt StrNCmp;
StrCpyOpt StrCpy; StrLenOpt StrLen; MemCmpOpt MemCmp; MemCpyOpt MemCpy;
MemMoveOpt MemMove; MemSetOpt MemSet;
// Math Library Optimizations
PowOpt Pow; Exp2Opt Exp2; UnaryDoubleFPOpt UnaryDoubleFP;
// Integer Optimizations
@ -1242,6 +1297,8 @@ void SimplifyLibCalls::InitOptimizations() {
Optimizations["strlen"] = &StrLen;
Optimizations["memcmp"] = &MemCmp;
Optimizations["memcpy"] = &MemCpy;
Optimizations["memmove"] = &MemMove;
Optimizations["memset"] = &MemSet;
// Math Library Optimizations
Optimizations["powf"] = &Pow;
@ -1386,10 +1443,6 @@ bool SimplifyLibCalls::runOnFunction(Function &F) {
// * memcmp(x,y,l) -> cnst
// (if all arguments are constant and strlen(x) <= l and strlen(y) <= l)
//
// memmove:
// * memmove(d,s,l,a) -> memcpy(d,s,l,a)
// (if s is a global constant array)
//
// pow, powf, powl:
// * pow(exp(x),y) -> exp(x*y)
// * pow(sqrt(x),y) -> pow(x,y*0.5)

12
llvm/test/Transforms/SimplifyLibCalls/memmove.ll Normal file
View File

@ -0,0 +1,12 @@
; RUN: llvm-as < %s | opt -simplify-libcalls | llvm-dis | grep {llvm.memmove}
target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:32:32"
target triple = "i686-pc-linux-gnu"
define i8* @test(i8* %a, i8* %b, i32 %x) {
entry:
%call = call i8* @memmove(i8* %a, i8* %b, i32 %x )
ret i8* %call
}
declare i8* @memmove(i8*,i8*,i32)

12
llvm/test/Transforms/SimplifyLibCalls/memset.ll Normal file
View File

@ -0,0 +1,12 @@
; RUN: llvm-as < %s | opt -simplify-libcalls | llvm-dis | grep {llvm.memset}
target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:32:32"
target triple = "i686-pc-linux-gnu"
define i8* @test(i8* %a, i32 %b, i32 %x) {
entry:
%call = call i8* @memset(i8* %a, i32 %b, i32 %x )
ret i8* %call
}
declare i8* @memset(i8*,i32,i32)