Commit dd9234a1 authored by Meador Inge's avatar Meador Inge
Browse files

instcombine: Migrate memcpy optimizations 

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

llvm-svn: 167686
parent 3b99dc62

llvm/lib/Transforms/Scalar/SimplifyLibCalls.cpp

+1 −24
Original line number Diff line number Diff line
@@ -104,28 +104,6 @@ static bool CallHasFloatingPointArgument(const CallInst *CI) { 
//===----------------------------------------------------------------------===//



namespace {

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

// 'memcpy' Optimizations



struct MemCpyOpt : 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)->isPointerTy() ||

        FT->getParamType(2) != TD->getIntPtrType(*Context))

      return 0;



    // 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);

  }

};



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

// 'memmove' Optimizations
@@ -839,7 +817,7 @@ namespace { 


    StringMap<LibCallOptimization*> Optimizations;

    // Memory LibCall Optimizations

    MemCpyOpt MemCpy; MemMoveOpt MemMove; MemSetOpt MemSet;

    MemMoveOpt MemMove; MemSetOpt MemSet;

    // Math Library Optimizations

    CosOpt Cos; PowOpt Pow; Exp2Opt Exp2;

    UnaryDoubleFPOpt UnaryDoubleFP, UnsafeUnaryDoubleFP;
@@ -906,7 +884,6 @@ void SimplifyLibCalls::AddOpt(LibFunc::Func F1, LibFunc::Func F2, 
/// we know.

void SimplifyLibCalls::InitOptimizations() {

  // Memory LibCall Optimizations

  AddOpt(LibFunc::memcpy, &MemCpy);

  Optimizations["memmove"] = &MemMove;

  AddOpt(LibFunc::memset, &MemSet);

llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp

+21 −0
Original line number Diff line number Diff line
@@ -959,6 +959,25 @@ struct MemCmpOpt : public LibCallOptimization { 
  }

};



struct MemCpyOpt : 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)->isPointerTy() ||

        FT->getParamType(2) != TD->getIntPtrType(*Context))

      return 0;



    // 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);

  }

};



} // End anonymous namespace.



namespace llvm {
@@ -996,6 +1015,7 @@ class LibCallSimplifierImpl { 


  // Memory library call optimizations.

  MemCmpOpt MemCmp;

  MemCpyOpt MemCpy;



  void initOptimizations();

  void addOpt(LibFunc::Func F, LibCallOptimization* Opt);
@@ -1045,6 +1065,7 @@ void LibCallSimplifierImpl::initOptimizations() { 


  // Memory library call optimizations.

  addOpt(LibFunc::memcmp, &MemCmp);

  addOpt(LibFunc::memcpy, &MemCpy);

}



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

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

0 → 100644
+17 −0
Original line number Diff line number Diff line 
; Test that the memcpy 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* @memcpy(i8*, i8*, i32)



; Check memcpy(mem1, mem2, size) -> llvm.memcpy(mem1, mem2, size, 1).



define i8* @test_simplify1(i8* %mem1, i8* %mem2, i32 %size) {

; CHECK: @test_simplify1

  %ret = call i8* @memcpy(i8* %mem1, i8* %mem2, i32 %size)

; CHECK: call void @llvm.memcpy

  ret i8* %ret

; CHECK: ret i8* %mem1

}

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

0 → 100644
+17 −0
Original line number Diff line number Diff line 
; Test that the memcpy 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 @memcpy(i8*, i8*, i32)



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



define i8 @test_no_simplify1(i8* %mem1, i8* %mem2, i32 %size) {

; CHECK: @test_no_simplify1

  %ret = call i8 @memcpy(i8* %mem1, i8* %mem2, i32 %size)

; CHECK: call i8 @memcpy

  ret i8 %ret

; CHECK: ret i8 %ret

}