pull byval processing out to its own helper function.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122235 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2010-12-20 07:57:41 +00:00
parent 018fb767b9
commit e7ae705c32
2 changed files with 76 additions and 59 deletions

View File

@ -229,6 +229,71 @@ static void UpdateCallGraphAfterInlining(CallSite CS,
CallerNode->removeCallEdgeFor(CS);
}
static Value *HandleByValArgument(Value *Arg, Instruction *TheCall,
const Function *CalledFunc,
InlineFunctionInfo &IFI,
unsigned ByValAlignment) {
if (CalledFunc->onlyReadsMemory())
return Arg;
LLVMContext &Context = Arg->getContext();
const Type *AggTy = cast<PointerType>(Arg->getType())->getElementType();
const Type *VoidPtrTy = Type::getInt8PtrTy(Context);
// Create the alloca. If we have TargetData, use nice alignment.
unsigned Align = 1;
if (IFI.TD)
Align = IFI.TD->getPrefTypeAlignment(AggTy);
// If the byval had an alignment specified, we *must* use at least that
// alignment, as it is required by the byval argument (and uses of the
// pointer inside the callee).
Align = std::max(Align, ByValAlignment);
Function *Caller = TheCall->getParent()->getParent();
Value *NewAlloca = new AllocaInst(AggTy, 0, Align, Arg->getName(),
&*Caller->begin()->begin());
// Emit a memcpy.
const Type *Tys[3] = {VoidPtrTy, VoidPtrTy, Type::getInt64Ty(Context)};
Function *MemCpyFn = Intrinsic::getDeclaration(Caller->getParent(),
Intrinsic::memcpy,
Tys, 3);
Value *DestCast = new BitCastInst(NewAlloca, VoidPtrTy, "tmp", TheCall);
Value *SrcCast = new BitCastInst(Arg, VoidPtrTy, "tmp", TheCall);
Value *Size;
if (IFI.TD == 0)
Size = ConstantExpr::getSizeOf(AggTy);
else
Size = ConstantInt::get(Type::getInt64Ty(Context),
IFI.TD->getTypeStoreSize(AggTy));
// Always generate a memcpy of alignment 1 here because we don't know
// the alignment of the src pointer. Other optimizations can infer
// better alignment.
Value *CallArgs[] = {
DestCast, SrcCast, Size,
ConstantInt::get(Type::getInt32Ty(Context), 1),
ConstantInt::getFalse(Context) // isVolatile
};
CallInst *TheMemCpy =
CallInst::Create(MemCpyFn, CallArgs, CallArgs+5, "", TheCall);
// If we have a call graph, update it.
if (CallGraph *CG = IFI.CG) {
CallGraphNode *MemCpyCGN = CG->getOrInsertFunction(MemCpyFn);
CallGraphNode *CallerNode = (*CG)[Caller];
CallerNode->addCalledFunction(TheMemCpy, MemCpyCGN);
}
// Uses of the argument in the function should use our new alloca
// instead.
return NewAlloca;
}
// InlineFunction - This function inlines the called function into the basic
// block of the caller. This returns false if it is not possible to inline this
// call. The program is still in a well defined state if this occurs though.
@ -304,63 +369,14 @@ bool llvm::InlineFunction(CallSite CS, InlineFunctionInfo &IFI) {
// by them explicit. However, we don't do this if the callee is readonly
// or readnone, because the copy would be unneeded: the callee doesn't
// modify the struct.
if (CalledFunc->paramHasAttr(ArgNo+1, Attribute::ByVal) &&
!CalledFunc->onlyReadsMemory()) {
const Type *AggTy = cast<PointerType>(I->getType())->getElementType();
const Type *VoidPtrTy = Type::getInt8PtrTy(Context);
// Create the alloca. If we have TargetData, use nice alignment.
unsigned Align = 1;
if (IFI.TD)
Align = IFI.TD->getPrefTypeAlignment(AggTy);
// If the byval had an alignment specified, we *must* use at least that
// alignment, as it is required by the byval argument (and uses of the
// pointer inside the callee).
Align = std::max(Align, CalledFunc->getParamAlignment(ArgNo+1));
Value *NewAlloca = new AllocaInst(AggTy, 0, Align, I->getName(),
&*Caller->begin()->begin());
// Emit a memcpy.
const Type *Tys[3] = {VoidPtrTy, VoidPtrTy, Type::getInt64Ty(Context)};
Function *MemCpyFn = Intrinsic::getDeclaration(Caller->getParent(),
Intrinsic::memcpy,
Tys, 3);
Value *DestCast = new BitCastInst(NewAlloca, VoidPtrTy, "tmp", TheCall);
Value *SrcCast = new BitCastInst(*AI, VoidPtrTy, "tmp", TheCall);
Value *Size;
if (IFI.TD == 0)
Size = ConstantExpr::getSizeOf(AggTy);
else
Size = ConstantInt::get(Type::getInt64Ty(Context),
IFI.TD->getTypeStoreSize(AggTy));
// Always generate a memcpy of alignment 1 here because we don't know
// the alignment of the src pointer. Other optimizations can infer
// better alignment.
Value *CallArgs[] = {
DestCast, SrcCast, Size,
ConstantInt::get(Type::getInt32Ty(Context), 1),
ConstantInt::getFalse(Context) // isVolatile
};
CallInst *TheMemCpy =
CallInst::Create(MemCpyFn, CallArgs, CallArgs+5, "", TheCall);
// If we have a call graph, update it.
if (CallGraph *CG = IFI.CG) {
CallGraphNode *MemCpyCGN = CG->getOrInsertFunction(MemCpyFn);
CallGraphNode *CallerNode = (*CG)[Caller];
CallerNode->addCalledFunction(TheMemCpy, MemCpyCGN);
}
// Uses of the argument in the function should use our new alloca
// instead.
ActualArg = NewAlloca;
if (CalledFunc->paramHasAttr(ArgNo+1, Attribute::ByVal)) {
ActualArg = HandleByValArgument(ActualArg, TheCall, CalledFunc, IFI,
CalledFunc->getParamAlignment(ArgNo+1));
// Calls that we inline may use the new alloca, so we need to clear
// their 'tail' flags.
MustClearTailCallFlags = true;
// their 'tail' flags if HandleByValArgument introduced a new alloca and
// the callee has calls.
MustClearTailCallFlags |= ActualArg != *AI;
}
VMap[I] = ActualArg;

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@ -26,7 +26,8 @@ entry:
call void @f( %struct.ss* byval %S ) nounwind
ret i32 0
; CHECK: @test1()
; CHECK: %b = alloca %struct.ss
; CHECK: %S1 = alloca %struct.ss
; CHECK: %S = alloca %struct.ss
; CHECK: call void @llvm.memcpy
; CHECK: ret i32 0
}
@ -74,9 +75,9 @@ entry:
call void @f3( %struct.ss* byval align 64 %S) nounwind
ret void
; CHECK: @test3()
; CHECK: %b = alloca %struct.ss, align 64
; CHECK: %S1 = alloca %struct.ss, align 64
; CHECK: %S = alloca %struct.ss
; CHECK: call void @llvm.memcpy
; CHECK: call void @g3(%struct.ss* %b)
; CHECK: call void @g3(%struct.ss* %S1)
; CHECK: ret void
}