Commit 59fb1a05 authored by Bill Wendling's avatar Bill Wendling
Browse files

Fix Win64 va_arg. 

--- Merging r127328 into '.':
U    test/CodeGen/X86/win64_vararg.ll
U    lib/Target/X86/X86ISelLowering.cpp

llvm-svn: 128044
parent 265fa123

llvm/lib/Target/X86/X86ISelLowering.cpp

+5 −3
Original line number Diff line number Diff line
@@ -1750,8 +1750,8 @@ X86TargetLowering::LowerFormalArguments(SDValue Chain, 
  // If the function takes variable number of arguments, make a frame index for

  // the start of the first vararg value... for expansion of llvm.va_start.

  if (isVarArg) {

    if (!IsWin64 && (Is64Bit || (CallConv != CallingConv::X86_FastCall &&

                    CallConv != CallingConv::X86_ThisCall))) {

    if (Is64Bit || (CallConv != CallingConv::X86_FastCall &&

                    CallConv != CallingConv::X86_ThisCall)) {

      FuncInfo->setVarArgsFrameIndex(MFI->CreateFixedObject(1, StackSize,true));

    }

    if (Is64Bit) {
@@ -1803,6 +1803,8 @@ X86TargetLowering::LowerFormalArguments(SDValue Chain, 
        int HomeOffset = TFI.getOffsetOfLocalArea() + 8;

        FuncInfo->setRegSaveFrameIndex(

          MFI->CreateFixedObject(1, NumIntRegs * 8 + HomeOffset, false));

        // Fixup to set vararg frame on shadow area (4 x i64).

        if (NumIntRegs < 4)

          FuncInfo->setVarArgsFrameIndex(FuncInfo->getRegSaveFrameIndex());

      } else {

        // For X86-64, if there are vararg parameters that are passed via

llvm/test/CodeGen/X86/win64_vararg.ll

+33 −0
Original line number Diff line number Diff line
@@ -18,3 +18,36 @@ entry: 
}



declare void @llvm.va_start(i8*) nounwind



; CHECK: f5:

; CHECK: pushq

; CHECK: leaq 56(%rsp),

define i8* @f5(i64 %a0, i64 %a1, i64 %a2, i64 %a3, i64 %a4, ...) nounwind {

entry:

  %ap = alloca i8*, align 8

  %ap1 = bitcast i8** %ap to i8*

  call void @llvm.va_start(i8* %ap1)

  ret i8* %ap1

}



; CHECK: f4:

; CHECK: pushq

; CHECK: leaq 48(%rsp),

define i8* @f4(i64 %a0, i64 %a1, i64 %a2, i64 %a3, ...) nounwind {

entry:

  %ap = alloca i8*, align 8

  %ap1 = bitcast i8** %ap to i8*

  call void @llvm.va_start(i8* %ap1)

  ret i8* %ap1

}



; CHECK: f3:

; CHECK: pushq

; CHECK: leaq 40(%rsp),

define i8* @f3(i64 %a0, i64 %a1, i64 %a2, ...) nounwind {

entry:

  %ap = alloca i8*, align 8

  %ap1 = bitcast i8** %ap to i8*

  call void @llvm.va_start(i8* %ap1)

  ret i8* %ap1

}