Commit d4825780 authored by Meador Inge's avatar Meador Inge
Browse files

instcombine: Migrate memset optimizations 

This patch migrates the memset optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.

llvm-svn: 167689
parent 91380570

llvm/lib/Transforms/Scalar/SimplifyLibCalls.cpp

+0 −27
Original line number Diff line number Diff line
@@ -104,28 +104,6 @@ static bool CallHasFloatingPointArgument(const CallInst *CI) { 
//===----------------------------------------------------------------------===//



namespace {

//===---------------------------------------===//

// 'memset' Optimizations



struct MemSetOpt : public LibCallOptimization {

  virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {

    // These optimizations require DataLayout.

    if (!TD) return 0;



    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;



    // 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

//===----------------------------------------------------------------------===//
@@ -794,8 +772,6 @@ namespace { 
    TargetLibraryInfo *TLI;



    StringMap<LibCallOptimization*> Optimizations;

    // Memory LibCall Optimizations

    MemSetOpt MemSet;

    // Math Library Optimizations

    CosOpt Cos; PowOpt Pow; Exp2Opt Exp2;

    UnaryDoubleFPOpt UnaryDoubleFP, UnsafeUnaryDoubleFP;
@@ -861,9 +837,6 @@ void SimplifyLibCalls::AddOpt(LibFunc::Func F1, LibFunc::Func F2, 
/// Optimizations - Populate the Optimizations map with all the optimizations

/// we know.

void SimplifyLibCalls::InitOptimizations() {

  // Memory LibCall Optimizations

  AddOpt(LibFunc::memset, &MemSet);



  // Math Library Optimizations

  Optimizations["cosf"] = &Cos;

  Optimizations["cos"] = &Cos;

llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp

+21 −0
Original line number Diff line number Diff line
@@ -997,6 +997,25 @@ struct MemMoveOpt : public LibCallOptimization { 
  }

};



struct MemSetOpt : public LibCallOptimization {

  virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {

    // These optimizations require DataLayout.

    if (!TD) return 0;



    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;



    // 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);

  }

};



} // End anonymous namespace.



namespace llvm {
@@ -1036,6 +1055,7 @@ class LibCallSimplifierImpl { 
  MemCmpOpt MemCmp;

  MemCpyOpt MemCpy;

  MemMoveOpt MemMove;

  MemSetOpt MemSet;



  void initOptimizations();

  void addOpt(LibFunc::Func F, LibCallOptimization* Opt);
@@ -1087,6 +1107,7 @@ void LibCallSimplifierImpl::initOptimizations() { 
  addOpt(LibFunc::memcmp, &MemCmp);

  addOpt(LibFunc::memcpy, &MemCpy);

  addOpt(LibFunc::memmove, &MemMove);

  addOpt(LibFunc::memset, &MemSet);

}



Value *LibCallSimplifierImpl::optimizeCall(CallInst *CI) {

llvm/test/Transforms/InstCombine/memset-1.ll

0 → 100644
+17 −0
Original line number Diff line number Diff line 
; Test that the memset library call simplifier works correctly.

;

; RUN: opt < %s -instcombine -S | FileCheck %s



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-f80:128:128"



declare i8* @memset(i8*, i32, i32)



; Check memset(mem1, val, size) -> llvm.memset(mem1, val, size, 1).



define i8* @test_simplify1(i8* %mem, i32 %val, i32 %size) {

; CHECK: @test_simplify1

  %ret = call i8* @memset(i8* %mem, i32 %val, i32 %size)

; CHECK: call void @llvm.memset

  ret i8* %ret

; CHECK: ret i8* %mem

}

llvm/test/Transforms/InstCombine/memset-2.ll

0 → 100644
+17 −0
Original line number Diff line number Diff line 
; Test that the memset library call simplifier works correctly.

;

; RUN: opt < %s -instcombine -S | FileCheck %s



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-f80:128:128"



declare i8 @memset(i8*, i32, i32)



; Check that memset functions with the wrong prototype aren't simplified.



define i8 @test_no_simplify1(i8* %mem, i32 %val, i32 %size) {

; CHECK: @test_no_simplify1

  %ret = call i8 @memset(i8* %mem, i32 %val, i32 %size)

; CHECK: call i8 @memset

  ret i8 %ret

; CHECK: ret i8 %ret

}

llvm/test/Transforms/SimplifyLibCalls/memset-64.ll

deleted100644 → 0
+0 −12
Original line number Diff line number Diff line 
; RUN: opt < %s -simplify-libcalls -S | grep "llvm.memset"

target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128"

target triple = "x86_64-pc-linux-gnu"



define void @a(i8* %x) nounwind {

entry:

	%call = call i8* @memset(i8* %x, i32 1, i64 100)		; <i8*> [#uses=0]

	ret void

}



declare i8* @memset(i8*, i32, i64)