llvm-6502/lib/Target/X86/X86TargetObjectFile.cpp
Rafael Espindola 965e3bc5ff Use a consistent argument order in TargetLoweringObjectFile.
These methods normally call each other and it is really annoying if the
arguments are in different order. The more common rule was that the arguments
specific to call are first (GV, Encoding, Suffix) and the auxiliary objects
(Mang, TM) come after. This patch changes the exceptions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@201044 91177308-0d34-0410-b5e6-96231b3b80d8
2014-02-09 14:50:44 +00:00

107 lines
3.7 KiB
C++

//===-- X86TargetObjectFile.cpp - X86 Object Info -------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "X86TargetObjectFile.h"
#include "llvm/IR/Mangler.h"
#include "llvm/IR/Operator.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCSectionELF.h"
#include "llvm/Support/Dwarf.h"
using namespace llvm;
using namespace dwarf;
const MCExpr *X86_64MachoTargetObjectFile::getTTypeGlobalReference(
const GlobalValue *GV, unsigned Encoding, Mangler &Mang,
MachineModuleInfo *MMI, MCStreamer &Streamer) const {
// On Darwin/X86-64, we can reference dwarf symbols with foo@GOTPCREL+4, which
// is an indirect pc-relative reference.
if (Encoding & (DW_EH_PE_indirect | DW_EH_PE_pcrel)) {
const MCSymbol *Sym = getSymbol(GV, Mang);
const MCExpr *Res =
MCSymbolRefExpr::Create(Sym, MCSymbolRefExpr::VK_GOTPCREL, getContext());
const MCExpr *Four = MCConstantExpr::Create(4, getContext());
return MCBinaryExpr::CreateAdd(Res, Four, getContext());
}
return TargetLoweringObjectFileMachO::getTTypeGlobalReference(
GV, Encoding, Mang, MMI, Streamer);
}
MCSymbol *X86_64MachoTargetObjectFile::
getCFIPersonalitySymbol(const GlobalValue *GV, Mangler &Mang,
MachineModuleInfo *MMI) const {
return getSymbol(GV, Mang);
}
void
X86LinuxTargetObjectFile::Initialize(MCContext &Ctx, const TargetMachine &TM) {
TargetLoweringObjectFileELF::Initialize(Ctx, TM);
InitializeELF(TM.Options.UseInitArray);
}
const MCExpr *
X86LinuxTargetObjectFile::getDebugThreadLocalSymbol(
const MCSymbol *Sym) const {
return MCSymbolRefExpr::Create(Sym, MCSymbolRefExpr::VK_DTPOFF, getContext());
}
const MCExpr *
X86WindowsTargetObjectFile::getExecutableRelativeSymbol(const ConstantExpr *CE,
Mangler &Mang) const {
// We are looking for the difference of two symbols, need a subtraction
// operation.
const SubOperator *Sub = dyn_cast<SubOperator>(CE);
if (!Sub)
return 0;
// Symbols must first be numbers before we can subtract them, we need to see a
// ptrtoint on both subtraction operands.
const PtrToIntOperator *SubLHS =
dyn_cast<PtrToIntOperator>(Sub->getOperand(0));
const PtrToIntOperator *SubRHS =
dyn_cast<PtrToIntOperator>(Sub->getOperand(1));
if (!SubLHS || !SubRHS)
return 0;
// Our symbols should exist in address space zero, cowardly no-op if
// otherwise.
if (SubLHS->getPointerAddressSpace() != 0 ||
SubRHS->getPointerAddressSpace() != 0)
return 0;
// Both ptrtoint instructions must wrap global variables:
// - Only global variables are eligible for image relative relocations.
// - The subtrahend refers to the special symbol __ImageBase, a global.
const GlobalVariable *GVLHS =
dyn_cast<GlobalVariable>(SubLHS->getPointerOperand());
const GlobalVariable *GVRHS =
dyn_cast<GlobalVariable>(SubRHS->getPointerOperand());
if (!GVLHS || !GVRHS)
return 0;
// We expect __ImageBase to be a global variable without a section, externally
// defined.
//
// It should look something like this: @__ImageBase = external constant i8
if (GVRHS->isThreadLocal() || GVRHS->getName() != "__ImageBase" ||
!GVRHS->hasExternalLinkage() || GVRHS->hasInitializer() ||
GVRHS->hasSection())
return 0;
// An image-relative, thread-local, symbol makes no sense.
if (GVLHS->isThreadLocal())
return 0;
return MCSymbolRefExpr::Create(
getSymbol(GVLHS, Mang), MCSymbolRefExpr::VK_COFF_IMGREL32, getContext());
}