Correctly restore stack pointer after realignment in main() on Cygwin/Mingw32
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@42332 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86RegisterInfo.cpp b/lib/Target/X86/X86RegisterInfo.cpp
index f7cd84f..1fdee67 100644
--- a/lib/Target/X86/X86RegisterInfo.cpp
+++ b/lib/Target/X86/X86RegisterInfo.cpp
@@ -1545,7 +1545,9 @@
void X86RegisterInfo::emitEpilogue(MachineFunction &MF,
MachineBasicBlock &MBB) const {
const MachineFrameInfo *MFI = MF.getFrameInfo();
+ const Function* Fn = MF.getFunction();
X86MachineFunctionInfo *X86FI = MF.getInfo<X86MachineFunctionInfo>();
+ const X86Subtarget* Subtarget = &MF.getTarget().getSubtarget<X86Subtarget>();
MachineBasicBlock::iterator MBBI = prior(MBB.end());
unsigned RetOpcode = MBBI->getOpcode();
@@ -1602,7 +1604,12 @@
// If dynamic alloca is used, then reset esp to point to the last
// callee-saved slot before popping them off!
- if (MFI->hasVarSizedObjects()) {
+ // Also, if it's main() on Cygwin/Mingw32 we aligned stack in the prologue, - revert
+ // stack changes back. Note: we're assuming, that frame pointer was forced
+ // for main()
+ if (MFI->hasVarSizedObjects() ||
+ (Fn->hasExternalLinkage() && Fn->getName() == "main" &&
+ Subtarget->isTargetCygMing())) {
unsigned Opc = Is64Bit ? X86::LEA64r : X86::LEA32r;
if (CSSize) {
MachineInstr *MI = addRegOffset(BuildMI(TII.get(Opc), StackPtr),