diff options
Diffstat (limited to 'llvm/lib/Target/X86/X86FrameLowering.cpp')
-rw-r--r-- | llvm/lib/Target/X86/X86FrameLowering.cpp | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/llvm/lib/Target/X86/X86FrameLowering.cpp b/llvm/lib/Target/X86/X86FrameLowering.cpp index 8c029a8c22d..b1aa35048c9 100644 --- a/llvm/lib/Target/X86/X86FrameLowering.cpp +++ b/llvm/lib/Target/X86/X86FrameLowering.cpp @@ -849,6 +849,11 @@ void X86FrameLowering::emitEpilogue(MachineFunction &MF, unsigned FramePtr = RegInfo->getFrameRegister(MF); unsigned StackPtr = RegInfo->getStackRegister(); + bool IsWinEH = + MF.getTarget().getMCAsmInfo()->getExceptionHandlingType() == + ExceptionHandling::WinEH; + bool NeedsWinEH = IsWinEH && MF.getFunction()->needsUnwindTableEntry(); + switch (RetOpcode) { default: llvm_unreachable("Can only insert epilog into returning blocks"); @@ -933,17 +938,29 @@ void X86FrameLowering::emitEpilogue(MachineFunction &MF, unsigned Opc = getLEArOpcode(IsLP64); addRegOffset(BuildMI(MBB, MBBI, DL, TII.get(Opc), StackPtr), FramePtr, false, -CSSize); + --MBBI; } else { unsigned Opc = (Is64Bit ? X86::MOV64rr : X86::MOV32rr); BuildMI(MBB, MBBI, DL, TII.get(Opc), StackPtr) .addReg(FramePtr); + --MBBI; } } else if (NumBytes) { // Adjust stack pointer back: ESP += numbytes. emitSPUpdate(MBB, MBBI, StackPtr, NumBytes, Is64Bit, IsLP64, UseLEA, TII, *RegInfo); + --MBBI; } + // Windows unwinder will not invoke function's exception handler if IP is + // either in prologue or in epilogue. This behavior causes a problem when a + // call immediately precedes an epilogue, because the return address points + // into the epilogue. To cope with that, we insert an epilogue marker here, + // then replace it with a 'nop' if it ends up immediately after a CALL in the + // final emitted code. + if (NeedsWinEH) + BuildMI(MBB, MBBI, DL, TII.get(X86::SEH_Epilogue)); + // We're returning from function via eh_return. if (RetOpcode == X86::EH_RETURN || RetOpcode == X86::EH_RETURN64) { MBBI = MBB.getLastNonDebugInstr(); |