You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
119 lines
4.0 KiB
119 lines
4.0 KiB
//===-- SystemZMCAsmBackend.cpp - SystemZ 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/SystemZMCTargetDesc.h"
|
|
#include "MCTargetDesc/SystemZMCFixups.h"
|
|
#include "llvm/MC/MCAsmBackend.h"
|
|
#include "llvm/MC/MCELFObjectWriter.h"
|
|
#include "llvm/MC/MCFixupKindInfo.h"
|
|
#include "llvm/MC/MCInst.h"
|
|
#include "llvm/MC/MCObjectWriter.h"
|
|
|
|
using namespace llvm;
|
|
|
|
// Value is a fully-resolved relocation value: Symbol + Addend [- Pivot].
|
|
// Return the bits that should be installed in a relocation field for
|
|
// fixup kind Kind.
|
|
static uint64_t extractBitsForFixup(MCFixupKind Kind, uint64_t Value) {
|
|
if (Kind < FirstTargetFixupKind)
|
|
return Value;
|
|
|
|
switch (unsigned(Kind)) {
|
|
case SystemZ::FK_390_PC16DBL:
|
|
case SystemZ::FK_390_PC32DBL:
|
|
return (int64_t)Value / 2;
|
|
|
|
case SystemZ::FK_390_TLS_CALL:
|
|
return 0;
|
|
}
|
|
|
|
llvm_unreachable("Unknown fixup kind!");
|
|
}
|
|
|
|
namespace {
|
|
class SystemZMCAsmBackend : public MCAsmBackend {
|
|
uint8_t OSABI;
|
|
public:
|
|
SystemZMCAsmBackend(uint8_t osABI)
|
|
: OSABI(osABI) {}
|
|
|
|
// Override MCAsmBackend
|
|
unsigned getNumFixupKinds() const override {
|
|
return SystemZ::NumTargetFixupKinds;
|
|
}
|
|
const MCFixupKindInfo &getFixupKindInfo(MCFixupKind Kind) const override;
|
|
void applyFixup(const MCFixup &Fixup, char *Data, unsigned DataSize,
|
|
uint64_t Value, bool IsPCRel) const override;
|
|
bool mayNeedRelaxation(const MCInst &Inst) const override {
|
|
return false;
|
|
}
|
|
bool fixupNeedsRelaxation(const MCFixup &Fixup, uint64_t Value,
|
|
const MCRelaxableFragment *Fragment,
|
|
const MCAsmLayout &Layout) const override {
|
|
return false;
|
|
}
|
|
void relaxInstruction(const MCInst &Inst, const MCSubtargetInfo &STI,
|
|
MCInst &Res) const override {
|
|
llvm_unreachable("SystemZ does do not have assembler relaxation");
|
|
}
|
|
bool writeNopData(uint64_t Count, MCObjectWriter *OW) const override;
|
|
MCObjectWriter *createObjectWriter(raw_pwrite_stream &OS) const override {
|
|
return createSystemZObjectWriter(OS, OSABI);
|
|
}
|
|
};
|
|
} // end anonymous namespace
|
|
|
|
const MCFixupKindInfo &
|
|
SystemZMCAsmBackend::getFixupKindInfo(MCFixupKind Kind) const {
|
|
const static MCFixupKindInfo Infos[SystemZ::NumTargetFixupKinds] = {
|
|
{ "FK_390_PC16DBL", 0, 16, MCFixupKindInfo::FKF_IsPCRel },
|
|
{ "FK_390_PC32DBL", 0, 32, MCFixupKindInfo::FKF_IsPCRel },
|
|
{ "FK_390_TLS_CALL", 0, 0, 0 }
|
|
};
|
|
|
|
if (Kind < FirstTargetFixupKind)
|
|
return MCAsmBackend::getFixupKindInfo(Kind);
|
|
|
|
assert(unsigned(Kind - FirstTargetFixupKind) < getNumFixupKinds() &&
|
|
"Invalid kind!");
|
|
return Infos[Kind - FirstTargetFixupKind];
|
|
}
|
|
|
|
void SystemZMCAsmBackend::applyFixup(const MCFixup &Fixup, char *Data,
|
|
unsigned DataSize, uint64_t Value,
|
|
bool IsPCRel) const {
|
|
MCFixupKind Kind = Fixup.getKind();
|
|
unsigned Offset = Fixup.getOffset();
|
|
unsigned Size = (getFixupKindInfo(Kind).TargetSize + 7) / 8;
|
|
|
|
assert(Offset + Size <= DataSize && "Invalid fixup offset!");
|
|
|
|
// Big-endian insertion of Size bytes.
|
|
Value = extractBitsForFixup(Kind, Value);
|
|
unsigned ShiftValue = (Size * 8) - 8;
|
|
for (unsigned I = 0; I != Size; ++I) {
|
|
Data[Offset + I] |= uint8_t(Value >> ShiftValue);
|
|
ShiftValue -= 8;
|
|
}
|
|
}
|
|
|
|
bool SystemZMCAsmBackend::writeNopData(uint64_t Count,
|
|
MCObjectWriter *OW) const {
|
|
for (uint64_t I = 0; I != Count; ++I)
|
|
OW->write8(7);
|
|
return true;
|
|
}
|
|
|
|
MCAsmBackend *llvm::createSystemZMCAsmBackend(const Target &T,
|
|
const MCRegisterInfo &MRI,
|
|
const Triple &TT, StringRef CPU) {
|
|
uint8_t OSABI = MCELFObjectTargetWriter::getOSABI(TT.getOS());
|
|
return new SystemZMCAsmBackend(OSABI);
|
|
}
|