llvm-project/llvm/lib/CodeGen/AsmPrinter/Win64Exception.cpp

116 lines
3.9 KiB
C++

//===-- CodeGen/AsmPrinter/Win64Exception.cpp - Dwarf Exception Impl ------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains support for writing Win64 exception info into asm files.
//
//===----------------------------------------------------------------------===//
#include "DwarfException.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/Twine.h"
#include "llvm/CodeGen/AsmPrinter.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/Module.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCSection.h"
#include "llvm/MC/MCStreamer.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/Support/Dwarf.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/FormattedStream.h"
#include "llvm/Target/Mangler.h"
#include "llvm/Target/TargetFrameLowering.h"
#include "llvm/Target/TargetLoweringObjectFile.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetOptions.h"
#include "llvm/Target/TargetRegisterInfo.h"
using namespace llvm;
Win64Exception::Win64Exception(AsmPrinter *A)
: DwarfException(A),
shouldEmitPersonality(false), shouldEmitLSDA(false), shouldEmitMoves(false)
{}
Win64Exception::~Win64Exception() {}
/// EndModule - Emit all exception information that should come after the
/// content.
void Win64Exception::EndModule() {
}
/// BeginFunction - Gather pre-function exception information. Assumes it's
/// being emitted immediately after the function entry point.
void Win64Exception::BeginFunction(const MachineFunction *MF) {
shouldEmitMoves = shouldEmitPersonality = shouldEmitLSDA = false;
// If any landing pads survive, we need an EH table.
bool hasLandingPads = !MMI->getLandingPads().empty();
shouldEmitMoves = Asm->needsSEHMoves();
const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
unsigned PerEncoding = TLOF.getPersonalityEncoding();
const Function *Per = MMI->getPersonalities()[MMI->getPersonalityIndex()];
shouldEmitPersonality = hasLandingPads &&
PerEncoding != dwarf::DW_EH_PE_omit && Per;
unsigned LSDAEncoding = TLOF.getLSDAEncoding();
shouldEmitLSDA = shouldEmitPersonality &&
LSDAEncoding != dwarf::DW_EH_PE_omit;
if (!shouldEmitPersonality && !shouldEmitMoves)
return;
Asm->OutStreamer.EmitWin64EHStartProc(Asm->CurrentFnSym);
if (!shouldEmitPersonality)
return;
MCSymbol *GCCHandlerSym =
Asm->GetExternalSymbolSymbol("_GCC_specific_handler");
Asm->OutStreamer.EmitWin64EHHandler(GCCHandlerSym, true, true);
Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("eh_func_begin",
Asm->getFunctionNumber()));
}
/// EndFunction - Gather and emit post-function exception information.
///
void Win64Exception::EndFunction() {
if (!shouldEmitPersonality && !shouldEmitMoves)
return;
Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("eh_func_end",
Asm->getFunctionNumber()));
// Map all labels and get rid of any dead landing pads.
MMI->TidyLandingPads();
if (shouldEmitPersonality) {
const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
const Function *Per = MMI->getPersonalities()[MMI->getPersonalityIndex()];
const MCSymbol *Sym = TLOF.getCFIPersonalitySymbol(Per, Asm->Mang, MMI);
Asm->OutStreamer.PushSection();
Asm->OutStreamer.EmitWin64EHHandlerData();
Asm->OutStreamer.EmitValue(MCSymbolRefExpr::Create(Sym, Asm->OutContext),
4);
EmitExceptionTable();
Asm->OutStreamer.PopSection();
}
Asm->OutStreamer.EmitWin64EHEndProc();
}