X86: correct tail return address calculation

Due to the weird and wondeful usual arithmetic conversions, some
calculations involving negative values were getting performed in
uint32_t and then promoted to int64_t, which is really not a good
idea.

Patch by Katsuhiro Ueno.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187703 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Tim Northover 2013-08-04 09:35:57 +00:00
parent a2b0c335d8
commit a54b66277e
3 changed files with 25 additions and 4 deletions

View File

@ -1323,7 +1323,7 @@ X86FrameLowering::processFunctionBeforeCalleeSavedScan(MachineFunction &MF,
unsigned SlotSize = RegInfo->getSlotSize();
X86MachineFunctionInfo *X86FI = MF.getInfo<X86MachineFunctionInfo>();
int32_t TailCallReturnAddrDelta = X86FI->getTCReturnAddrDelta();
int64_t TailCallReturnAddrDelta = X86FI->getTCReturnAddrDelta();
if (TailCallReturnAddrDelta < 0) {
// create RETURNADDR area
@ -1336,7 +1336,7 @@ X86FrameLowering::processFunctionBeforeCalleeSavedScan(MachineFunction &MF,
// }
// [EBP]
MFI->CreateFixedObject(-TailCallReturnAddrDelta,
(-1U*SlotSize)+TailCallReturnAddrDelta, true);
TailCallReturnAddrDelta - SlotSize, true);
}
if (hasFP(MF)) {

View File

@ -2456,7 +2456,8 @@ EmitTailCallStoreRetAddr(SelectionDAG & DAG, MachineFunction &MF,
if (!FPDiff) return Chain;
// Calculate the new stack slot for the return address.
int NewReturnAddrFI =
MF.getFrameInfo()->CreateFixedObject(SlotSize, FPDiff-SlotSize, false);
MF.getFrameInfo()->CreateFixedObject(SlotSize, (int64_t)FPDiff - SlotSize,
false);
SDValue NewRetAddrFrIdx = DAG.getFrameIndex(NewReturnAddrFI, PtrVT);
Chain = DAG.getStore(Chain, dl, RetAddrFrIdx, NewRetAddrFrIdx,
MachinePointerInfo::getFixedStack(NewReturnAddrFI),
@ -3323,7 +3324,8 @@ SDValue X86TargetLowering::getReturnAddressFrameIndex(SelectionDAG &DAG) const {
if (ReturnAddrIndex == 0) {
// Set up a frame object for the return address.
unsigned SlotSize = RegInfo->getSlotSize();
ReturnAddrIndex = MF.getFrameInfo()->CreateFixedObject(SlotSize, -SlotSize,
ReturnAddrIndex = MF.getFrameInfo()->CreateFixedObject(SlotSize,
-(int64_t)SlotSize,
false);
FuncInfo->setRAIndex(ReturnAddrIndex);
}

View File

@ -0,0 +1,19 @@
; RUN: llc -march=x86 -tailcallopt < %s | FileCheck %s
target triple = "i686-apple-darwin"
declare fastcc void @foo(i32, i32, i32, i32, i32, i32)
declare i32* @bar(i32*)
define fastcc void @hoge(i32 %b) nounwind {
; Do not overwrite pushed callee-save registers
; CHECK: pushl
; CHECK: subl $[[SIZE:[0-9]+]], %esp
; CHECK-NOT: [[SIZE]](%esp)
%a = alloca i32
store i32 0, i32* %a
%d = tail call i32* @bar(i32* %a) nounwind
store i32 %b, i32* %d
tail call fastcc void @foo(i32 1, i32 2, i32 3, i32 4, i32 5, i32 6) nounwind
ret void
}