From d15f45f53e2d5f89b777b1c2d36de0b40f303a01 Mon Sep 17 00:00:00 2001 From: Bill Wendling Date: Thu, 9 Jul 2009 22:30:02 +0000 Subject: [PATCH] If -fomit-frame-pointer is used, we still need to record when the %esp register is modified. Otherwise, the unwinder will get confused. The old code (before I started my hacking) did this. It dropped on the floor, because I wasn't aware of this requirement. On the plus side, if we use "alloca" in a function, we create frame pointers even with -fomit-frame-pointer is enabled! This is a Good Thing(tm)!!! git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75183 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Target/X86/X86RegisterInfo.cpp | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-) diff --git a/lib/Target/X86/X86RegisterInfo.cpp b/lib/Target/X86/X86RegisterInfo.cpp index be4764e2768..c9d3950217b 100644 --- a/lib/Target/X86/X86RegisterInfo.cpp +++ b/lib/Target/X86/X86RegisterInfo.cpp @@ -873,7 +873,7 @@ void X86RegisterInfo::emitPrologue(MachineFunction &MF) const { BuildMI(MBB, MBBI, DL, TII.get(X86::DBG_LABEL)).addImm(LabelId); // Emit DWARF info specifying the offsets of the callee-saved registers. - emitCalleeSavedFrameMoves(MF, LabelId, FramePtr); + emitCalleeSavedFrameMoves(MF, LabelId, HasFP ? FramePtr : StackPtr); } if (MBBI != MBB.end()) @@ -931,6 +931,25 @@ void X86RegisterInfo::emitPrologue(MachineFunction &MF) const { if (NumBytes) emitSPUpdate(MBB, MBBI, StackPtr, -(int64_t)NumBytes, Is64Bit, TII); } + + if (!HasFP && needsFrameMoves && NumBytes) { + // Mark end of stack pointer adjustment. + unsigned LabelId = MMI->NextLabelID(); + BuildMI(MBB, MBBI, DL, TII.get(X86::DBG_LABEL)).addImm(LabelId); + + // Define the current CFA rule to use the provided offset. + if (StackSize) { + MachineLocation SPDst(MachineLocation::VirtualFP); + MachineLocation SPSrc(MachineLocation::VirtualFP, + -StackSize + stackGrowth); + Moves.push_back(MachineMove(LabelId, SPDst, SPSrc)); + } else { + // FIXME: Verify & implement for FP + MachineLocation SPDst(StackPtr); + MachineLocation SPSrc(StackPtr, stackGrowth); + Moves.push_back(MachineMove(LabelId, SPDst, SPSrc)); + } + } } void X86RegisterInfo::emitEpilogue(MachineFunction &MF,