RPCS3/llvm-mirror
1
0
Fork 0
mirror of https://github.com/RPCS3/llvm-mirror.git synced 2024-12-28 14:36:34 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity
fa5c3ec6b4
llvm-mirror/lib/MC/MCAssembler.cpp

870 lines
27 KiB
C++
Raw Blame History

//===- lib/MC/MCAssembler.cpp - Assembler Backend Implementation ----------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "assembler"
#include "llvm/MC/MCAssembler.h"
#include "llvm/MC/MCAsmLayout.h"
#include "llvm/MC/MCCodeEmitter.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCObjectWriter.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/MC/MCValue.h"
#include "llvm/ADT/OwningPtr.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/Twine.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Support/Debug.h"
#include "llvm/Target/TargetRegistry.h"
#include "llvm/Target/TargetAsmBackend.h"
// FIXME: Gross.
#include "../Target/X86/X86FixupKinds.h"
#include <vector>
using namespace llvm;
STATISTIC(EmittedFragments, "Number of emitted assembler fragments");
// FIXME FIXME FIXME: There are number of places in this file where we convert
// what is a 64-bit assembler value used for computation into a value in the
// object file, which may truncate it. We should detect that truncation where
// invalid and report errors back.
/* *** */
MCFragment::MCFragment() : Kind(FragmentType(~0)) {
}
MCFragment::MCFragment(FragmentType _Kind, MCSectionData *_Parent)
: Kind(_Kind),
Parent(_Parent),
FileSize(~UINT64_C(0))
{
if (Parent)
Parent->getFragmentList().push_back(this);
}
MCFragment::~MCFragment() {
}
uint64_t MCFragment::getAddress() const {
assert(getParent() && "Missing Section!");
return getParent()->getAddress() + Offset;
}
/* *** */
MCSectionData::MCSectionData() : Section(0) {}
MCSectionData::MCSectionData(const MCSection &_Section, MCAssembler *A)
: Section(&_Section),
Alignment(1),
Address(~UINT64_C(0)),
Size(~UINT64_C(0)),
FileSize(~UINT64_C(0)),
HasInstructions(false)
{
if (A)
A->getSectionList().push_back(this);
}
/* *** */
MCSymbolData::MCSymbolData() : Symbol(0) {}
MCSymbolData::MCSymbolData(const MCSymbol &_Symbol, MCFragment *_Fragment,
uint64_t _Offset, MCAssembler *A)
: Symbol(&_Symbol), Fragment(_Fragment), Offset(_Offset),
IsExternal(false), IsPrivateExtern(false),
CommonSize(0), CommonAlign(0), Flags(0), Index(0)
{
if (A)
A->getSymbolList().push_back(this);
}
/* *** */
MCAssembler::MCAssembler(MCContext &_Context, TargetAsmBackend &_Backend,
MCCodeEmitter &_Emitter, raw_ostream &_OS)
: Context(_Context), Backend(_Backend), Emitter(_Emitter),
OS(_OS), SubsectionsViaSymbols(false)
{
}
MCAssembler::~MCAssembler() {
}
static bool isScatteredFixupFullyResolvedSimple(const MCAssembler &Asm,
const MCAsmFixup &Fixup,
const MCDataFragment *DF,
const MCValue Target,
const MCSection *BaseSection) {
// The effective fixup address is
// addr(atom(A)) + offset(A)
// - addr(atom(B)) - offset(B)
// - addr(<base symbol>) + <fixup offset from base symbol>
// and the offsets are not relocatable, so the fixup is fully resolved when
// addr(atom(A)) - addr(atom(B)) - addr(<base symbol>)) == 0.
//
// The simple (Darwin, except on x86_64) way of dealing with this was to
// assume that any reference to a temporary symbol *must* be a temporary
// symbol in the same atom, unless the sections differ. Therefore, any PCrel
// relocation to a temporary symbol (in the same section) is fully
// resolved. This also works in conjunction with absolutized .set, which
// requires the compiler to use .set to absolutize the differences between
// symbols which the compiler knows to be assembly time constants, so we don't
// need to worry about consider symbol differences fully resolved.
// Non-relative fixups are only resolved if constant.
if (!BaseSection)
return Target.isAbsolute();
// Otherwise, relative fixups are only resolved if not a difference and the
// target is a temporary in the same section.
if (Target.isAbsolute() || Target.getSymB())
return false;
const MCSymbol *A = &Target.getSymA()->getSymbol();
if (!A->isTemporary() || !A->isInSection() ||
&A->getSection() != BaseSection)
return false;
return true;
}
static bool isScatteredFixupFullyResolved(const MCAssembler &Asm,
const MCAsmFixup &Fixup,
const MCDataFragment *DF,
const MCValue Target,
const MCSymbolData *BaseSymbol) {
// The effective fixup address is
// addr(atom(A)) + offset(A)
// - addr(atom(B)) - offset(B)
// - addr(BaseSymbol) + <fixup offset from base symbol>
// and the offsets are not relocatable, so the fixup is fully resolved when
// addr(atom(A)) - addr(atom(B)) - addr(BaseSymbol) == 0.
//
// Note that "false" is almost always conservatively correct (it means we emit
// a relocation which is unnecessary), except when it would force us to emit a
// relocation which the target cannot encode.
const MCSymbolData *A_Base = 0, *B_Base = 0;
if (const MCSymbolRefExpr *A = Target.getSymA()) {
// Modified symbol references cannot be resolved.
if (A->getKind() != MCSymbolRefExpr::VK_None)
return false;
A_Base = Asm.getAtom(&Asm.getSymbolData(A->getSymbol()));
if (!A_Base)
return false;
}
if (const MCSymbolRefExpr *B = Target.getSymB()) {
// Modified symbol references cannot be resolved.
if (B->getKind() != MCSymbolRefExpr::VK_None)
return false;
B_Base = Asm.getAtom(&Asm.getSymbolData(B->getSymbol()));
if (!B_Base)
return false;
}
// If there is no base, A and B have to be the same atom for this fixup to be
// fully resolved.
if (!BaseSymbol)
return A_Base == B_Base;
// Otherwise, B must be missing and A must be the base.
return !B_Base && BaseSymbol == A_Base;
}
bool MCAssembler::isSymbolLinkerVisible(const MCSymbolData *SD) const {
// Non-temporary labels should always be visible to the linker.
if (!SD->getSymbol().isTemporary())
return true;
// Absolute temporary labels are never visible.
if (!SD->getFragment())
return false;
// Otherwise, check if the section requires symbols even for temporary labels.
return getBackend().doesSectionRequireSymbols(
SD->getFragment()->getParent()->getSection());
}
const MCSymbolData *MCAssembler::getAtomForAddress(const MCSectionData *Section,
uint64_t Address) const {
const MCSymbolData *Best = 0;
for (MCAssembler::const_symbol_iterator it = symbol_begin(),
ie = symbol_end(); it != ie; ++it) {
// Ignore non-linker visible symbols.
if (!isSymbolLinkerVisible(it))
continue;
// Ignore symbols not in the same section.
if (!it->getFragment() || it->getFragment()->getParent() != Section)
continue;
// Otherwise, find the closest symbol preceding this address (ties are
// resolved in favor of the last defined symbol).
if (it->getAddress() <= Address &&
(!Best || it->getAddress() >= Best->getAddress()))
Best = it;
}
return Best;
}
const MCSymbolData *MCAssembler::getAtom(const MCSymbolData *SD) const {
// Linker visible symbols define atoms.
if (isSymbolLinkerVisible(SD))
return SD;
// Absolute and undefined symbols have no defining atom.
if (!SD->getFragment())
return 0;
// Otherwise, search by address.
return getAtomForAddress(SD->getFragment()->getParent(), SD->getAddress());
}
bool MCAssembler::EvaluateFixup(const MCAsmLayout &Layout, MCAsmFixup &Fixup,
MCDataFragment *DF,
MCValue &Target, uint64_t &Value) const {
if (!Fixup.Value->EvaluateAsRelocatable(Target, &Layout))
llvm_report_error("expected relocatable expression");
// FIXME: How do non-scattered symbols work in ELF? I presume the linker
// doesn't support small relocations, but then under what criteria does the
// assembler allow symbol differences?
Value = Target.getConstant();
bool IsPCRel =
Emitter.getFixupKindInfo(Fixup.Kind).Flags & MCFixupKindInfo::FKF_IsPCRel;
bool IsResolved = true;
if (const MCSymbolRefExpr *A = Target.getSymA()) {
if (A->getSymbol().isDefined())
Value += getSymbolData(A->getSymbol()).getAddress();
else
IsResolved = false;
}
if (const MCSymbolRefExpr *B = Target.getSymB()) {
if (B->getSymbol().isDefined())
Value -= getSymbolData(B->getSymbol()).getAddress();
else
IsResolved = false;
}
// If we are using scattered symbols, determine whether this value is actually
// resolved; scattering may cause atoms to move.
if (IsResolved && getBackend().hasScatteredSymbols()) {
if (getBackend().hasReliableSymbolDifference()) {
// If this is a PCrel relocation, find the base atom (identified by its
// symbol) that the fixup value is relative to.
const MCSymbolData *BaseSymbol = 0;
if (IsPCRel) {
BaseSymbol = getAtomForAddress(
DF->getParent(), DF->getAddress() + Fixup.Offset);
if (!BaseSymbol)
IsResolved = false;
}
if (IsResolved)
IsResolved = isScatteredFixupFullyResolved(*this, Fixup, DF, Target,
BaseSymbol);
} else {
const MCSection *BaseSection = 0;
if (IsPCRel)
BaseSection = &DF->getParent()->getSection();
IsResolved = isScatteredFixupFullyResolvedSimple(*this, Fixup, DF, Target,
BaseSection);
}
}
if (IsPCRel)
Value -= DF->getAddress() + Fixup.Offset;
return IsResolved;
}
void MCAssembler::LayoutSection(MCSectionData &SD,
MCAsmLayout &Layout) {
uint64_t Address = SD.getAddress();
for (MCSectionData::iterator it = SD.begin(), ie = SD.end(); it != ie; ++it) {
MCFragment &F = *it;
F.setOffset(Address - SD.getAddress());
// Evaluate fragment size.
switch (F.getKind()) {
case MCFragment::FT_Align: {
MCAlignFragment &AF = cast<MCAlignFragment>(F);
uint64_t Size = OffsetToAlignment(Address, AF.getAlignment());
if (Size > AF.getMaxBytesToEmit())
AF.setFileSize(0);
else
AF.setFileSize(Size);
break;
}
case MCFragment::FT_Data:
F.setFileSize(cast<MCDataFragment>(F).getContents().size());
break;
case MCFragment::FT_Fill: {
MCFillFragment &FF = cast<MCFillFragment>(F);
F.setFileSize(FF.getValueSize() * FF.getCount());
break;
}
case MCFragment::FT_Org: {
MCOrgFragment &OF = cast<MCOrgFragment>(F);
int64_t TargetLocation;
if (!OF.getOffset().EvaluateAsAbsolute(TargetLocation, &Layout))
llvm_report_error("expected assembly-time absolute expression");
// FIXME: We need a way to communicate this error.
int64_t Offset = TargetLocation - F.getOffset();
if (Offset < 0)
llvm_report_error("invalid .org offset '" + Twine(TargetLocation) +
"' (at offset '" + Twine(F.getOffset()) + "'");
F.setFileSize(Offset);
break;
}
case MCFragment::FT_ZeroFill: {
MCZeroFillFragment &ZFF = cast<MCZeroFillFragment>(F);
// Align the fragment offset; it is safe to adjust the offset freely since
// this is only in virtual sections.
Address = RoundUpToAlignment(Address, ZFF.getAlignment());
F.setOffset(Address - SD.getAddress());
// FIXME: This is misnamed.
F.setFileSize(ZFF.getSize());
break;
}
}
Address += F.getFileSize();
}
// Set the section sizes.
SD.setSize(Address - SD.getAddress());
if (getBackend().isVirtualSection(SD.getSection()))
SD.setFileSize(0);
else
SD.setFileSize(Address - SD.getAddress());
}
/// WriteNopData - Write optimal nops to the output file for the \arg Count
/// bytes. This returns the number of bytes written. It may return 0 if
/// the \arg Count is more than the maximum optimal nops.
///
/// FIXME this is X86 32-bit specific and should move to a better place.
static uint64_t WriteNopData(uint64_t Count, MCObjectWriter *OW) {
static const uint8_t Nops[16][16] = {
// nop
{0x90},
// xchg %ax,%ax
{0x66, 0x90},
// nopl (%[re]ax)
{0x0f, 0x1f, 0x00},
// nopl 0(%[re]ax)
{0x0f, 0x1f, 0x40, 0x00},
// nopl 0(%[re]ax,%[re]ax,1)
{0x0f, 0x1f, 0x44, 0x00, 0x00},
// nopw 0(%[re]ax,%[re]ax,1)
{0x66, 0x0f, 0x1f, 0x44, 0x00, 0x00},
// nopl 0L(%[re]ax)
{0x0f, 0x1f, 0x80, 0x00, 0x00, 0x00, 0x00},
// nopl 0L(%[re]ax,%[re]ax,1)
{0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00},
// nopw 0L(%[re]ax,%[re]ax,1)
{0x66, 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00},
// nopw %cs:0L(%[re]ax,%[re]ax,1)
{0x66, 0x2e, 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00},
// nopl 0(%[re]ax,%[re]ax,1)
// nopw 0(%[re]ax,%[re]ax,1)
{0x0f, 0x1f, 0x44, 0x00, 0x00,
0x66, 0x0f, 0x1f, 0x44, 0x00, 0x00},
// nopw 0(%[re]ax,%[re]ax,1)
// nopw 0(%[re]ax,%[re]ax,1)
{0x66, 0x0f, 0x1f, 0x44, 0x00, 0x00,
0x66, 0x0f, 0x1f, 0x44, 0x00, 0x00},
// nopw 0(%[re]ax,%[re]ax,1)
// nopl 0L(%[re]ax) */
{0x66, 0x0f, 0x1f, 0x44, 0x00, 0x00,
0x0f, 0x1f, 0x80, 0x00, 0x00, 0x00, 0x00},
// nopl 0L(%[re]ax)
// nopl 0L(%[re]ax)
{0x0f, 0x1f, 0x80, 0x00, 0x00, 0x00, 0x00,
0x0f, 0x1f, 0x80, 0x00, 0x00, 0x00, 0x00},
// nopl 0L(%[re]ax)
// nopl 0L(%[re]ax,%[re]ax,1)
{0x0f, 0x1f, 0x80, 0x00, 0x00, 0x00, 0x00,
0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00}
};
if (Count > 15)
return 0;
for (uint64_t i = 0; i < Count; i++)
OW->Write8(uint8_t(Nops[Count - 1][i]));
return Count;
}
/// WriteFragmentData - Write the \arg F data to the output file.
static void WriteFragmentData(const MCFragment &F, MCObjectWriter *OW) {
uint64_t Start = OW->getStream().tell();
(void) Start;
++EmittedFragments;
// FIXME: Embed in fragments instead?
switch (F.getKind()) {
case MCFragment::FT_Align: {
MCAlignFragment &AF = cast<MCAlignFragment>(F);
uint64_t Count = AF.getFileSize() / AF.getValueSize();
// FIXME: This error shouldn't actually occur (the front end should emit
// multiple .align directives to enforce the semantics it wants), but is
// severe enough that we want to report it. How to handle this?
if (Count * AF.getValueSize() != AF.getFileSize())
llvm_report_error("undefined .align directive, value size '" +
Twine(AF.getValueSize()) +
"' is not a divisor of padding size '" +
Twine(AF.getFileSize()) + "'");
// See if we are aligning with nops, and if so do that first to try to fill
// the Count bytes. Then if that did not fill any bytes or there are any
// bytes left to fill use the the Value and ValueSize to fill the rest.
if (AF.getEmitNops()) {
uint64_t NopByteCount = WriteNopData(Count, OW);
Count -= NopByteCount;
}
for (uint64_t i = 0; i != Count; ++i) {
switch (AF.getValueSize()) {
default:
assert(0 && "Invalid size!");
case 1: OW->Write8 (uint8_t (AF.getValue())); break;
case 2: OW->Write16(uint16_t(AF.getValue())); break;
case 4: OW->Write32(uint32_t(AF.getValue())); break;
case 8: OW->Write64(uint64_t(AF.getValue())); break;
}
}
break;
}
case MCFragment::FT_Data: {
OW->WriteBytes(cast<MCDataFragment>(F).getContents().str());
break;
}
case MCFragment::FT_Fill: {
MCFillFragment &FF = cast<MCFillFragment>(F);
for (uint64_t i = 0, e = FF.getCount(); i != e; ++i) {
switch (FF.getValueSize()) {
default:
assert(0 && "Invalid size!");
case 1: OW->Write8 (uint8_t (FF.getValue())); break;
case 2: OW->Write16(uint16_t(FF.getValue())); break;
case 4: OW->Write32(uint32_t(FF.getValue())); break;
case 8: OW->Write64(uint64_t(FF.getValue())); break;
}
}
break;
}
case MCFragment::FT_Org: {
MCOrgFragment &OF = cast<MCOrgFragment>(F);
for (uint64_t i = 0, e = OF.getFileSize(); i != e; ++i)
OW->Write8(uint8_t(OF.getValue()));
break;
}
case MCFragment::FT_ZeroFill: {
assert(0 && "Invalid zero fill fragment in concrete section!");
break;
}
}
assert(OW->getStream().tell() - Start == F.getFileSize());
}
void MCAssembler::WriteSectionData(const MCSectionData *SD,
MCObjectWriter *OW) const {
// Ignore virtual sections.
if (getBackend().isVirtualSection(SD->getSection())) {
assert(SD->getFileSize() == 0);
return;
}
uint64_t Start = OW->getStream().tell();
(void) Start;
for (MCSectionData::const_iterator it = SD->begin(),
ie = SD->end(); it != ie; ++it)
WriteFragmentData(*it, OW);
// Add section padding.
assert(SD->getFileSize() >= SD->getSize() && "Invalid section sizes!");
OW->WriteZeros(SD->getFileSize() - SD->getSize());
assert(OW->getStream().tell() - Start == SD->getFileSize());
}
void MCAssembler::Finish() {
DEBUG_WITH_TYPE("mc-dump", {
llvm::errs() << "assembler backend - pre-layout\n--\n";
dump(); });
// Layout until everything fits.
MCAsmLayout Layout(*this);
while (LayoutOnce(Layout))
continue;
DEBUG_WITH_TYPE("mc-dump", {
llvm::errs() << "assembler backend - post-layout\n--\n";
dump(); });
llvm::OwningPtr<MCObjectWriter> Writer(getBackend().createObjectWriter(OS));
if (!Writer)
llvm_report_error("unable to create object writer!");
// Allow the object writer a chance to perform post-layout binding (for
// example, to set the index fields in the symbol data).
Writer->ExecutePostLayoutBinding(*this);
// Evaluate and apply the fixups, generating relocation entries as necessary.
for (MCAssembler::iterator it = begin(), ie = end(); it != ie; ++it) {
for (MCSectionData::iterator it2 = it->begin(),
ie2 = it->end(); it2 != ie2; ++it2) {
MCDataFragment *DF = dyn_cast<MCDataFragment>(it2);
if (!DF)
continue;
for (MCDataFragment::fixup_iterator it3 = DF->fixup_begin(),
ie3 = DF->fixup_end(); it3 != ie3; ++it3) {
MCAsmFixup &Fixup = *it3;
// Evaluate the fixup.
MCValue Target;
uint64_t FixedValue;
if (!EvaluateFixup(Layout, Fixup, DF, Target, FixedValue)) {
// The fixup was unresolved, we need a relocation. Inform the object
// writer of the relocation, and give it an opportunity to adjust the
// fixup value if need be.
Writer->RecordRelocation(*this, DF, Fixup, Target, FixedValue);
}
getBackend().ApplyFixup(Fixup, *DF, FixedValue);
}
}
}
// Write the object file.
Writer->WriteObject(*this);
OS.flush();
}
bool MCAssembler::FixupNeedsRelaxation(MCAsmFixup &Fixup, MCDataFragment *DF,
const MCAsmLayout &Layout) const {
// Currently we only need to relax X86::reloc_pcrel_1byte.
if (unsigned(Fixup.Kind) != X86::reloc_pcrel_1byte)
return false;
// If we cannot resolve the fixup value, it requires relaxation.
MCValue Target;
uint64_t Value;
if (!EvaluateFixup(Layout, Fixup, DF, Target, Value))
return true;
// Otherwise, relax if the value is too big for a (signed) i8.
return int64_t(Value) != int64_t(int8_t(Value));
}
bool MCAssembler::LayoutOnce(MCAsmLayout &Layout) {
// Layout the concrete sections and fragments.
uint64_t Address = 0;
MCSectionData *Prev = 0;
for (iterator it = begin(), ie = end(); it != ie; ++it) {
MCSectionData &SD = *it;
// Skip virtual sections.
if (getBackend().isVirtualSection(SD.getSection()))
continue;
// Align this section if necessary by adding padding bytes to the previous
// section.
if (uint64_t Pad = OffsetToAlignment(Address, it->getAlignment())) {
assert(Prev && "Missing prev section!");
Prev->setFileSize(Prev->getFileSize() + Pad);
Address += Pad;
}
// Layout the section fragments and its size.
SD.setAddress(Address);
LayoutSection(SD, Layout);
Address += SD.getFileSize();
Prev = &SD;
}
// Layout the virtual sections.
for (iterator it = begin(), ie = end(); it != ie; ++it) {
MCSectionData &SD = *it;
if (!getBackend().isVirtualSection(SD.getSection()))
continue;
// Align this section if necessary by adding padding bytes to the previous
// section.
if (uint64_t Pad = OffsetToAlignment(Address, it->getAlignment()))
Address += Pad;
SD.setAddress(Address);
LayoutSection(SD, Layout);
Address += SD.getSize();
}
// Scan the fixups in order and relax any that don't fit.
for (iterator it = begin(), ie = end(); it != ie; ++it) {
MCSectionData &SD = *it;
for (MCSectionData::iterator it2 = SD.begin(),
ie2 = SD.end(); it2 != ie2; ++it2) {
MCDataFragment *DF = dyn_cast<MCDataFragment>(it2);
if (!DF)
continue;
for (MCDataFragment::fixup_iterator it3 = DF->fixup_begin(),
ie3 = DF->fixup_end(); it3 != ie3; ++it3) {
MCAsmFixup &Fixup = *it3;
// Check whether we need to relax this fixup.
if (!FixupNeedsRelaxation(Fixup, DF, Layout))
continue;
// Relax the instruction.
//
// FIXME: This is a huge temporary hack which just looks for x86
// branches; the only thing we need to relax on x86 is
// 'X86::reloc_pcrel_1byte'. Once we have MCInst fragments, this will be
// replaced by a TargetAsmBackend hook (most likely tblgen'd) to relax
// an individual MCInst.
SmallVectorImpl<char> &C = DF->getContents();
uint64_t PrevOffset = Fixup.Offset;
unsigned Amt = 0;
// jcc instructions
if (unsigned(C[Fixup.Offset-1]) >= 0x70 &&
unsigned(C[Fixup.Offset-1]) <= 0x7f) {
C[Fixup.Offset] = C[Fixup.Offset-1] + 0x10;
C[Fixup.Offset-1] = char(0x0f);
++Fixup.Offset;
Amt = 4;
// jmp rel8
} else if (C[Fixup.Offset-1] == char(0xeb)) {
C[Fixup.Offset-1] = char(0xe9);
Amt = 3;
} else
llvm_unreachable("unknown 1 byte pcrel instruction!");
Fixup.Value = MCBinaryExpr::Create(
MCBinaryExpr::Sub, Fixup.Value,
MCConstantExpr::Create(3, getContext()),
getContext());
C.insert(C.begin() + Fixup.Offset, Amt, char(0));
Fixup.Kind = MCFixupKind(X86::reloc_pcrel_4byte);
// Update the remaining fixups, which have slid.
//
// FIXME: This is bad for performance, but will be eliminated by the
// move to MCInst specific fragments.
++it3;
for (; it3 != ie3; ++it3)
it3->Offset += Amt;
// Update all the symbols for this fragment, which may have slid.
//
// FIXME: This is really really bad for performance, but will be
// eliminated by the move to MCInst specific fragments.
for (MCAssembler::symbol_iterator it = symbol_begin(),
ie = symbol_end(); it != ie; ++it) {
MCSymbolData &SD = *it;
if (it->getFragment() != DF)
continue;
if (SD.getOffset() > PrevOffset)
SD.setOffset(SD.getOffset() + Amt);
}
// Restart layout.
//
// FIXME: This is O(N^2), but will be eliminated once we have a smart
// MCAsmLayout object.
return true;
}
}
}
return false;
}
// Debugging methods
namespace llvm {
raw_ostream &operator<<(raw_ostream &OS, const MCAsmFixup &AF) {
OS << "<MCAsmFixup" << " Offset:" << AF.Offset << " Value:" << *AF.Value
<< " Kind:" << AF.Kind << ">";
return OS;
}
}
void MCFragment::dump() {
raw_ostream &OS = llvm::errs();
OS << "<MCFragment " << (void*) this << " Offset:" << Offset
<< " FileSize:" << FileSize;
OS << ">";
}
void MCAlignFragment::dump() {
raw_ostream &OS = llvm::errs();
OS << "<MCAlignFragment ";
this->MCFragment::dump();
OS << "\n ";
OS << " Alignment:" << getAlignment()
<< " Value:" << getValue() << " ValueSize:" << getValueSize()
<< " MaxBytesToEmit:" << getMaxBytesToEmit() << ">";
}
void MCDataFragment::dump() {
raw_ostream &OS = llvm::errs();
OS << "<MCDataFragment ";
this->MCFragment::dump();
OS << "\n ";
OS << " Contents:[";
for (unsigned i = 0, e = getContents().size(); i != e; ++i) {
if (i) OS << ",";
OS << hexdigit((Contents[i] >> 4) & 0xF) << hexdigit(Contents[i] & 0xF);
}
OS << "] (" << getContents().size() << " bytes)";
if (!getFixups().empty()) {
OS << ",\n ";
OS << " Fixups:[";
for (fixup_iterator it = fixup_begin(), ie = fixup_end(); it != ie; ++it) {
if (it != fixup_begin()) OS << ",\n ";
OS << *it;
}
OS << "]";
}
OS << ">";
}
void MCFillFragment::dump() {
raw_ostream &OS = llvm::errs();
OS << "<MCFillFragment ";
this->MCFragment::dump();
OS << "\n ";
OS << " Value:" << getValue() << " ValueSize:" << getValueSize()
<< " Count:" << getCount() << ">";
}
void MCOrgFragment::dump() {
raw_ostream &OS = llvm::errs();
OS << "<MCOrgFragment ";
this->MCFragment::dump();
OS << "\n ";
OS << " Offset:" << getOffset() << " Value:" << getValue() << ">";
}
void MCZeroFillFragment::dump() {
raw_ostream &OS = llvm::errs();
OS << "<MCZeroFillFragment ";
this->MCFragment::dump();
OS << "\n ";
OS << " Size:" << getSize() << " Alignment:" << getAlignment() << ">";
}
void MCSectionData::dump() {
raw_ostream &OS = llvm::errs();
OS << "<MCSectionData";
OS << " Alignment:" << getAlignment() << " Address:" << Address
<< " Size:" << Size << " FileSize:" << FileSize
<< " Fragments:[\n ";
for (iterator it = begin(), ie = end(); it != ie; ++it) {
if (it != begin()) OS << ",\n ";
it->dump();
}
OS << "]>";
}
void MCSymbolData::dump() {
raw_ostream &OS = llvm::errs();
OS << "<MCSymbolData Symbol:" << getSymbol()
<< " Fragment:" << getFragment() << " Offset:" << getOffset()
<< " Flags:" << getFlags() << " Index:" << getIndex();
if (isCommon())
OS << " (common, size:" << getCommonSize()
<< " align: " << getCommonAlignment() << ")";
if (isExternal())
OS << " (external)";
if (isPrivateExtern())
OS << " (private extern)";
OS << ">";
}
void MCAssembler::dump() {
raw_ostream &OS = llvm::errs();
OS << "<MCAssembler\n";
OS << " Sections:[\n ";
for (iterator it = begin(), ie = end(); it != ie; ++it) {
if (it != begin()) OS << ",\n ";
it->dump();
}
OS << "],\n";
OS << " Symbols:[";
for (symbol_iterator it = symbol_begin(), ie = symbol_end(); it != ie; ++it) {
if (it != symbol_begin()) OS << ",\n ";
it->dump();
}
OS << "]>\n";
}
Reference in New Issue View Git Blame Copy Permalink