[COFF, ARM64] Implement support for SEH extensions __try/__except/__finally
Summary:
This patch supports MS SEH extensions __try/__except/__finally. The intrinsics localescape and localrecover are responsible for communicating escaped static allocas from the try block to the handler.
We need to preserve frame pointers for SEH. So we create a new function/property HasLocalEscape.
Reviewers: rnk, compnerd, mstorsjo, TomTan, efriedma, ssijaric
Reviewed By: rnk, efriedma
Subscribers: smeenai, jrmuizel, alex, majnemer, ssijaric, ehsan, dmajor, kristina, javed.absar, kristof.beyls, chrib, llvm-commits
Differential Revision: https://reviews.llvm.org/D53540
llvm-svn: 351370
diff --git a/llvm/lib/CodeGen/AsmPrinter/WinException.cpp b/llvm/lib/CodeGen/AsmPrinter/WinException.cpp
index cf8e8c6..92df09b 100644
--- a/llvm/lib/CodeGen/AsmPrinter/WinException.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/WinException.cpp
@@ -545,15 +545,17 @@
OS.AddComment(Comment);
};
- // Emit a label assignment with the SEH frame offset so we can use it for
- // llvm.eh.recoverfp.
- StringRef FLinkageName =
- GlobalValue::dropLLVMManglingEscape(MF->getFunction().getName());
- MCSymbol *ParentFrameOffset =
- Ctx.getOrCreateParentFrameOffsetSymbol(FLinkageName);
- const MCExpr *MCOffset =
- MCConstantExpr::create(FuncInfo.SEHSetFrameOffset, Ctx);
- Asm->OutStreamer->EmitAssignment(ParentFrameOffset, MCOffset);
+ if (!isAArch64) {
+ // Emit a label assignment with the SEH frame offset so we can use it for
+ // llvm.eh.recoverfp.
+ StringRef FLinkageName =
+ GlobalValue::dropLLVMManglingEscape(MF->getFunction().getName());
+ MCSymbol *ParentFrameOffset =
+ Ctx.getOrCreateParentFrameOffsetSymbol(FLinkageName);
+ const MCExpr *MCOffset =
+ MCConstantExpr::create(FuncInfo.SEHSetFrameOffset, Ctx);
+ Asm->OutStreamer->EmitAssignment(ParentFrameOffset, MCOffset);
+ }
// Use the assembler to compute the number of table entries through label
// difference and division.
@@ -937,6 +939,9 @@
if (FI != INT_MAX) {
const TargetFrameLowering *TFI = Asm->MF->getSubtarget().getFrameLowering();
unsigned UnusedReg;
+ // FIXME: getFrameIndexReference needs to match the behavior of
+ // AArch64RegisterInfo::hasBasePointer in which one of the scenarios where
+ // SP is used is if frame size >= 256.
Offset = TFI->getFrameIndexReference(*Asm->MF, FI, UnusedReg);
}