llvm-6502/lib/Target/ARM/MCTargetDesc/ARMWinCOFFObjectWriter.cpp
Saleem Abdulrasool 3f6dea4864 ARM: fail less catastrophically on invalid Windows input
Windows supports a restricted set of relocations (compared to ARM ELF).  In some
cases, we may end up generating an unsupported relocation.  This can occur with
bad input to the assembler in particular (the frontend should never generate
code that cannot be compiled).  Generate an error rather than just aborting.

The change in the API is driven by the desire to provide a slightly more helpful
message for debugging purposes.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226779 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-22 04:03:32 +00:00

91 lines
3.0 KiB
C++

//===-- ARMWinCOFFObjectWriter.cpp - ARM Windows COFF Object Writer -- C++ -==//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "MCTargetDesc/ARMFixupKinds.h"
#include "llvm/MC/MCAsmBackend.h"
#include "llvm/MC/MCFixup.h"
#include "llvm/MC/MCFixupKindInfo.h"
#include "llvm/MC/MCValue.h"
#include "llvm/MC/MCWinCOFFObjectWriter.h"
#include "llvm/ADT/Twine.h"
#include "llvm/Support/COFF.h"
#include "llvm/Support/Debug.h"
using namespace llvm;
namespace {
class ARMWinCOFFObjectWriter : public MCWinCOFFObjectTargetWriter {
public:
ARMWinCOFFObjectWriter(bool Is64Bit)
: MCWinCOFFObjectTargetWriter(COFF::IMAGE_FILE_MACHINE_ARMNT) {
assert(!Is64Bit && "AArch64 support not yet implemented");
}
virtual ~ARMWinCOFFObjectWriter() { }
unsigned getRelocType(const MCValue &Target, const MCFixup &Fixup,
bool IsCrossSection,
const MCAsmBackend &MAB) const override;
bool recordRelocation(const MCFixup &) const override;
};
unsigned ARMWinCOFFObjectWriter::getRelocType(const MCValue &Target,
const MCFixup &Fixup,
bool IsCrossSection,
const MCAsmBackend &MAB) const {
assert(getMachine() == COFF::IMAGE_FILE_MACHINE_ARMNT &&
"AArch64 support not yet implemented");
MCSymbolRefExpr::VariantKind Modifier =
Target.isAbsolute() ? MCSymbolRefExpr::VK_None : Target.getSymA()->getKind();
switch (static_cast<unsigned>(Fixup.getKind())) {
default: {
const MCFixupKindInfo &Info = MAB.getFixupKindInfo(Fixup.getKind());
report_fatal_error(Twine("unsupported relocation type: ") + Info.Name);
}
case FK_Data_4:
switch (Modifier) {
case MCSymbolRefExpr::VK_COFF_IMGREL32:
return COFF::IMAGE_REL_ARM_ADDR32NB;
case MCSymbolRefExpr::VK_SECREL:
return COFF::IMAGE_REL_ARM_SECREL;
default:
return COFF::IMAGE_REL_ARM_ADDR32;
}
case FK_SecRel_2:
return COFF::IMAGE_REL_ARM_SECTION;
case FK_SecRel_4:
return COFF::IMAGE_REL_ARM_SECREL;
case ARM::fixup_t2_condbranch:
return COFF::IMAGE_REL_ARM_BRANCH20T;
case ARM::fixup_t2_uncondbranch:
return COFF::IMAGE_REL_ARM_BRANCH24T;
case ARM::fixup_arm_thumb_bl:
case ARM::fixup_arm_thumb_blx:
return COFF::IMAGE_REL_ARM_BLX23T;
case ARM::fixup_t2_movw_lo16:
case ARM::fixup_t2_movt_hi16:
return COFF::IMAGE_REL_ARM_MOV32T;
}
}
bool ARMWinCOFFObjectWriter::recordRelocation(const MCFixup &Fixup) const {
return static_cast<unsigned>(Fixup.getKind()) != ARM::fixup_t2_movt_hi16;
}
}
namespace llvm {
MCObjectWriter *createARMWinCOFFObjectWriter(raw_ostream &OS, bool Is64Bit) {
MCWinCOFFObjectTargetWriter *MOTW = new ARMWinCOFFObjectWriter(Is64Bit);
return createWinCOFFObjectWriter(MOTW, OS);
}
}