mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-09-06 09:54:49 +00:00
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@149961 91177308-0d34-0410-b5e6-96231b3b80d8
171 lines
4.9 KiB
C++
171 lines
4.9 KiB
C++
//===-- MBlazeAsmBackend.cpp - MBlaze Assembler Backend -------------------===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "MCTargetDesc/MBlazeMCTargetDesc.h"
|
|
#include "llvm/MC/MCAsmBackend.h"
|
|
#include "llvm/MC/MCAssembler.h"
|
|
#include "llvm/MC/MCAsmLayout.h"
|
|
#include "llvm/MC/MCELFObjectWriter.h"
|
|
#include "llvm/MC/MCELFSymbolFlags.h"
|
|
#include "llvm/MC/MCExpr.h"
|
|
#include "llvm/MC/MCObjectWriter.h"
|
|
#include "llvm/MC/MCSectionELF.h"
|
|
#include "llvm/MC/MCSectionMachO.h"
|
|
#include "llvm/MC/MCValue.h"
|
|
#include "llvm/ADT/Twine.h"
|
|
#include "llvm/Support/ELF.h"
|
|
#include "llvm/Support/ErrorHandling.h"
|
|
#include "llvm/Support/TargetRegistry.h"
|
|
#include "llvm/Support/raw_ostream.h"
|
|
using namespace llvm;
|
|
|
|
static unsigned getFixupKindSize(unsigned Kind) {
|
|
switch (Kind) {
|
|
default: llvm_unreachable("invalid fixup kind!");
|
|
case FK_Data_1: return 1;
|
|
case FK_PCRel_2:
|
|
case FK_Data_2: return 2;
|
|
case FK_PCRel_4:
|
|
case FK_Data_4: return 4;
|
|
case FK_Data_8: return 8;
|
|
}
|
|
}
|
|
|
|
|
|
namespace {
|
|
|
|
class MBlazeAsmBackend : public MCAsmBackend {
|
|
public:
|
|
MBlazeAsmBackend(const Target &T)
|
|
: MCAsmBackend() {
|
|
}
|
|
|
|
unsigned getNumFixupKinds() const {
|
|
return 2;
|
|
}
|
|
|
|
bool mayNeedRelaxation(const MCInst &Inst) const;
|
|
|
|
bool fixupNeedsRelaxation(const MCFixup &Fixup,
|
|
uint64_t Value,
|
|
const MCInstFragment *DF,
|
|
const MCAsmLayout &Layout) const;
|
|
|
|
void relaxInstruction(const MCInst &Inst, MCInst &Res) const;
|
|
|
|
bool writeNopData(uint64_t Count, MCObjectWriter *OW) const;
|
|
|
|
unsigned getPointerSize() const {
|
|
return 4;
|
|
}
|
|
};
|
|
|
|
static unsigned getRelaxedOpcode(unsigned Op) {
|
|
switch (Op) {
|
|
default: return Op;
|
|
case MBlaze::ADDIK: return MBlaze::ADDIK32;
|
|
case MBlaze::ORI: return MBlaze::ORI32;
|
|
case MBlaze::BRLID: return MBlaze::BRLID32;
|
|
}
|
|
}
|
|
|
|
bool MBlazeAsmBackend::mayNeedRelaxation(const MCInst &Inst) const {
|
|
if (getRelaxedOpcode(Inst.getOpcode()) == Inst.getOpcode())
|
|
return false;
|
|
|
|
bool hasExprOrImm = false;
|
|
for (unsigned i = 0; i < Inst.getNumOperands(); ++i)
|
|
hasExprOrImm |= Inst.getOperand(i).isExpr();
|
|
|
|
return hasExprOrImm;
|
|
}
|
|
|
|
bool MBlazeAsmBackend::fixupNeedsRelaxation(const MCFixup &Fixup,
|
|
uint64_t Value,
|
|
const MCInstFragment *DF,
|
|
const MCAsmLayout &Layout) const {
|
|
// FIXME: Is this right? It's what the "generic" code was doing before,
|
|
// but is X86 specific. Is it actually true for MBlaze also, or was it
|
|
// just close enough to not be a big deal?
|
|
//
|
|
// Relax if the value is too big for a (signed) i8.
|
|
return int64_t(Value) != int64_t(int8_t(Value));
|
|
}
|
|
|
|
void MBlazeAsmBackend::relaxInstruction(const MCInst &Inst, MCInst &Res) const {
|
|
Res = Inst;
|
|
Res.setOpcode(getRelaxedOpcode(Inst.getOpcode()));
|
|
}
|
|
|
|
bool MBlazeAsmBackend::writeNopData(uint64_t Count, MCObjectWriter *OW) const {
|
|
if ((Count % 4) != 0)
|
|
return false;
|
|
|
|
for (uint64_t i = 0; i < Count; i += 4)
|
|
OW->Write32(0x00000000);
|
|
|
|
return true;
|
|
}
|
|
} // end anonymous namespace
|
|
|
|
namespace {
|
|
class ELFMBlazeAsmBackend : public MBlazeAsmBackend {
|
|
public:
|
|
uint8_t OSABI;
|
|
ELFMBlazeAsmBackend(const Target &T, uint8_t _OSABI)
|
|
: MBlazeAsmBackend(T), OSABI(_OSABI) { }
|
|
|
|
void applyFixup(const MCFixup &Fixup, char *Data, unsigned DataSize,
|
|
uint64_t Value) const;
|
|
|
|
MCObjectWriter *createObjectWriter(raw_ostream &OS) const {
|
|
return createMBlazeELFObjectWriter(OS, OSABI);
|
|
}
|
|
};
|
|
|
|
void ELFMBlazeAsmBackend::applyFixup(const MCFixup &Fixup, char *Data,
|
|
unsigned DataSize, uint64_t Value) const {
|
|
unsigned Size = getFixupKindSize(Fixup.getKind());
|
|
|
|
assert(Fixup.getOffset() + Size <= DataSize &&
|
|
"Invalid fixup offset!");
|
|
|
|
char *data = Data + Fixup.getOffset();
|
|
switch (Size) {
|
|
default: llvm_unreachable("Cannot fixup unknown value.");
|
|
case 1: llvm_unreachable("Cannot fixup 1 byte value.");
|
|
case 8: llvm_unreachable("Cannot fixup 8 byte value.");
|
|
|
|
case 4:
|
|
*(data+7) = uint8_t(Value);
|
|
*(data+6) = uint8_t(Value >> 8);
|
|
*(data+3) = uint8_t(Value >> 16);
|
|
*(data+2) = uint8_t(Value >> 24);
|
|
break;
|
|
|
|
case 2:
|
|
*(data+3) = uint8_t(Value >> 0);
|
|
*(data+2) = uint8_t(Value >> 8);
|
|
}
|
|
}
|
|
} // end anonymous namespace
|
|
|
|
MCAsmBackend *llvm::createMBlazeAsmBackend(const Target &T, StringRef TT) {
|
|
Triple TheTriple(TT);
|
|
|
|
if (TheTriple.isOSDarwin())
|
|
assert(0 && "Mac not supported on MBlaze");
|
|
|
|
if (TheTriple.isOSWindows())
|
|
assert(0 && "Windows not supported on MBlaze");
|
|
|
|
uint8_t OSABI = MCELFObjectTargetWriter::getOSABI(TheTriple.getOS());
|
|
return new ELFMBlazeAsmBackend(T, OSABI);
|
|
}
|