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llvm-6502/lib/MC/MCAsmStreamer.cpp
David Blaikie 5759c3a029 MCStreamer: Reimplement the virtual EmitRawText as a protected member, EmitRawTextImpl, to avoid string literal ambiguities 
Also improve the implementation of EmitRawText(Twine) so it doesn't
bother using the SmallString buffer if the Twine is a simple StringRef
anyway.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193378 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-24 22:43:10 +00:00

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//===- lib/MC/MCAsmStreamer.cpp - Text Assembly Output --------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "llvm/MC/MCStreamer.h"
#include "llvm/ADT/OwningPtr.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/Twine.h"
#include "llvm/MC/MCAsmBackend.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCCodeEmitter.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCFixupKindInfo.h"
#include "llvm/MC/MCInst.h"
#include "llvm/MC/MCInstPrinter.h"
#include "llvm/MC/MCObjectFileInfo.h"
#include "llvm/MC/MCRegisterInfo.h"
#include "llvm/MC/MCSectionCOFF.h"
#include "llvm/MC/MCSectionMachO.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/Format.h"
#include "llvm/Support/FormattedStream.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/Support/Path.h"
#include <cctype>
using namespace llvm;
namespace {
class MCAsmStreamer : public MCStreamer {
protected:
formatted_raw_ostream &OS;
const MCAsmInfo *MAI;
private:
OwningPtr<MCInstPrinter> InstPrinter;
OwningPtr<MCCodeEmitter> Emitter;
OwningPtr<MCAsmBackend> AsmBackend;
SmallString<128> CommentToEmit;
raw_svector_ostream CommentStream;
unsigned IsVerboseAsm : 1;
unsigned ShowInst : 1;
unsigned UseLoc : 1;
unsigned UseCFI : 1;
unsigned UseDwarfDirectory : 1;
enum EHSymbolFlags { EHGlobal = 1,
EHWeakDefinition = 1 << 1,
EHPrivateExtern = 1 << 2 };
DenseMap<const MCSymbol*, unsigned> FlagMap;
bool needsSet(const MCExpr *Value);
void EmitRegisterName(int64_t Register);
virtual void EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame);
virtual void EmitCFIEndProcImpl(MCDwarfFrameInfo &Frame);
public:
MCAsmStreamer(MCContext &Context, MCTargetStreamer *TargetStreamer,
formatted_raw_ostream &os, bool isVerboseAsm, bool useLoc,
bool useCFI, bool useDwarfDirectory, MCInstPrinter *printer,
MCCodeEmitter *emitter, MCAsmBackend *asmbackend, bool showInst)
: MCStreamer(Context, TargetStreamer), OS(os), MAI(Context.getAsmInfo()),
InstPrinter(printer), Emitter(emitter), AsmBackend(asmbackend),
CommentStream(CommentToEmit), IsVerboseAsm(isVerboseAsm),
ShowInst(showInst), UseLoc(useLoc), UseCFI(useCFI),
UseDwarfDirectory(useDwarfDirectory) {
if (InstPrinter && IsVerboseAsm)
InstPrinter->setCommentStream(CommentStream);
}
~MCAsmStreamer() {}
inline void EmitEOL() {
// If we don't have any comments, just emit a \n.
if (!IsVerboseAsm) {
OS << '\n';
return;
}
EmitCommentsAndEOL();
}
void EmitCommentsAndEOL();
/// isVerboseAsm - Return true if this streamer supports verbose assembly at
/// all.
virtual bool isVerboseAsm() const { return IsVerboseAsm; }
/// hasRawTextSupport - We support EmitRawText.
virtual bool hasRawTextSupport() const { return true; }
/// AddComment - Add a comment that can be emitted to the generated .s
/// file if applicable as a QoI issue to make the output of the compiler
/// more readable. This only affects the MCAsmStreamer, and only when
/// verbose assembly output is enabled.
virtual void AddComment(const Twine &T);
/// AddEncodingComment - Add a comment showing the encoding of an instruction.
virtual void AddEncodingComment(const MCInst &Inst);
/// GetCommentOS - Return a raw_ostream that comments can be written to.
/// Unlike AddComment, you are required to terminate comments with \n if you
/// use this method.
virtual raw_ostream &GetCommentOS() {
if (!IsVerboseAsm)
return nulls(); // Discard comments unless in verbose asm mode.
return CommentStream;
}
/// AddBlankLine - Emit a blank line to a .s file to pretty it up.
virtual void AddBlankLine() {
EmitEOL();
}
/// @name MCStreamer Interface
/// @{
virtual void ChangeSection(const MCSection *Section,
const MCExpr *Subsection);
virtual void InitSections() {
InitToTextSection();
}
virtual void InitToTextSection() {
SwitchSection(getContext().getObjectFileInfo()->getTextSection());
}
virtual void EmitLabel(MCSymbol *Symbol);
virtual void EmitDebugLabel(MCSymbol *Symbol);
virtual void EmitEHSymAttributes(const MCSymbol *Symbol,
MCSymbol *EHSymbol);
virtual void EmitAssemblerFlag(MCAssemblerFlag Flag);
virtual void EmitLinkerOptions(ArrayRef<std::string> Options);
virtual void EmitDataRegion(MCDataRegionType Kind);
virtual void EmitThumbFunc(MCSymbol *Func);
virtual void EmitAssignment(MCSymbol *Symbol, const MCExpr *Value);
virtual void EmitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol);
virtual void EmitDwarfAdvanceLineAddr(int64_t LineDelta,
const MCSymbol *LastLabel,
const MCSymbol *Label,
unsigned PointerSize);
virtual void EmitDwarfAdvanceFrameAddr(const MCSymbol *LastLabel,
const MCSymbol *Label);
virtual bool EmitSymbolAttribute(MCSymbol *Symbol, MCSymbolAttr Attribute);
virtual void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue);
virtual void BeginCOFFSymbolDef(const MCSymbol *Symbol);
virtual void EmitCOFFSymbolStorageClass(int StorageClass);
virtual void EmitCOFFSymbolType(int Type);
virtual void EndCOFFSymbolDef();
virtual void EmitCOFFSecRel32(MCSymbol const *Symbol);
virtual void EmitELFSize(MCSymbol *Symbol, const MCExpr *Value);
virtual void EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
unsigned ByteAlignment);
/// EmitLocalCommonSymbol - Emit a local common (.lcomm) symbol.
///
/// @param Symbol - The common symbol to emit.
/// @param Size - The size of the common symbol.
/// @param ByteAlignment - The alignment of the common symbol in bytes.
virtual void EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
unsigned ByteAlignment);
virtual void EmitZerofill(const MCSection *Section, MCSymbol *Symbol = 0,
uint64_t Size = 0, unsigned ByteAlignment = 0);
virtual void EmitTBSSSymbol (const MCSection *Section, MCSymbol *Symbol,
uint64_t Size, unsigned ByteAlignment = 0);
virtual void EmitBytes(StringRef Data);
virtual void EmitValueImpl(const MCExpr *Value, unsigned Size);
virtual void EmitIntValue(uint64_t Value, unsigned Size);
virtual void EmitULEB128Value(const MCExpr *Value);
virtual void EmitSLEB128Value(const MCExpr *Value);
virtual void EmitGPRel64Value(const MCExpr *Value);
virtual void EmitGPRel32Value(const MCExpr *Value);
virtual void EmitFill(uint64_t NumBytes, uint8_t FillValue);
virtual void EmitValueToAlignment(unsigned ByteAlignment, int64_t Value = 0,
unsigned ValueSize = 1,
unsigned MaxBytesToEmit = 0);
virtual void EmitCodeAlignment(unsigned ByteAlignment,
unsigned MaxBytesToEmit = 0);
virtual bool EmitValueToOffset(const MCExpr *Offset,
unsigned char Value = 0);
virtual void EmitFileDirective(StringRef Filename);
virtual bool EmitDwarfFileDirective(unsigned FileNo, StringRef Directory,
StringRef Filename, unsigned CUID = 0);
virtual void EmitDwarfLocDirective(unsigned FileNo, unsigned Line,
unsigned Column, unsigned Flags,
unsigned Isa, unsigned Discriminator,
StringRef FileName);
virtual void EmitIdent(StringRef IdentString);
virtual void EmitCFISections(bool EH, bool Debug);
virtual void EmitCFIDefCfa(int64_t Register, int64_t Offset);
virtual void EmitCFIDefCfaOffset(int64_t Offset);
virtual void EmitCFIDefCfaRegister(int64_t Register);
virtual void EmitCFIOffset(int64_t Register, int64_t Offset);
virtual void EmitCFIPersonality(const MCSymbol *Sym, unsigned Encoding);
virtual void EmitCFILsda(const MCSymbol *Sym, unsigned Encoding);
virtual void EmitCFIRememberState();
virtual void EmitCFIRestoreState();
virtual void EmitCFISameValue(int64_t Register);
virtual void EmitCFIRelOffset(int64_t Register, int64_t Offset);
virtual void EmitCFIAdjustCfaOffset(int64_t Adjustment);
virtual void EmitCFISignalFrame();
virtual void EmitCFIUndefined(int64_t Register);
virtual void EmitCFIRegister(int64_t Register1, int64_t Register2);
virtual void EmitCFIWindowSave();
virtual void EmitWin64EHStartProc(const MCSymbol *Symbol);
virtual void EmitWin64EHEndProc();
virtual void EmitWin64EHStartChained();
virtual void EmitWin64EHEndChained();
virtual void EmitWin64EHHandler(const MCSymbol *Sym, bool Unwind,
bool Except);
virtual void EmitWin64EHHandlerData();
virtual void EmitWin64EHPushReg(unsigned Register);
virtual void EmitWin64EHSetFrame(unsigned Register, unsigned Offset);
virtual void EmitWin64EHAllocStack(unsigned Size);
virtual void EmitWin64EHSaveReg(unsigned Register, unsigned Offset);
virtual void EmitWin64EHSaveXMM(unsigned Register, unsigned Offset);
virtual void EmitWin64EHPushFrame(bool Code);
virtual void EmitWin64EHEndProlog();
virtual void EmitInstruction(const MCInst &Inst);
virtual void EmitBundleAlignMode(unsigned AlignPow2);
virtual void EmitBundleLock(bool AlignToEnd);
virtual void EmitBundleUnlock();
/// EmitRawText - If this file is backed by an assembly streamer, this dumps
/// the specified string in the output .s file. This capability is
/// indicated by the hasRawTextSupport() predicate.
virtual void EmitRawTextImpl(StringRef String);
virtual void FinishImpl();
};
} // end anonymous namespace.
/// AddComment - Add a comment that can be emitted to the generated .s
/// file if applicable as a QoI issue to make the output of the compiler
/// more readable. This only affects the MCAsmStreamer, and only when
/// verbose assembly output is enabled.
void MCAsmStreamer::AddComment(const Twine &T) {
if (!IsVerboseAsm) return;
// Make sure that CommentStream is flushed.
CommentStream.flush();
T.toVector(CommentToEmit);
// Each comment goes on its own line.
CommentToEmit.push_back('\n');
// Tell the comment stream that the vector changed underneath it.
CommentStream.resync();
}
void MCAsmStreamer::EmitCommentsAndEOL() {
if (CommentToEmit.empty() && CommentStream.GetNumBytesInBuffer() == 0) {
OS << '\n';
return;
}
CommentStream.flush();
StringRef Comments = CommentToEmit.str();
assert(Comments.back() == '\n' &&
"Comment array not newline terminated");
do {
// Emit a line of comments.
OS.PadToColumn(MAI->getCommentColumn());
size_t Position = Comments.find('\n');
OS << MAI->getCommentString() << ' ' << Comments.substr(0, Position) <<'\n';
Comments = Comments.substr(Position+1);
} while (!Comments.empty());
CommentToEmit.clear();
// Tell the comment stream that the vector changed underneath it.
CommentStream.resync();
}
static inline int64_t truncateToSize(int64_t Value, unsigned Bytes) {
assert(Bytes && "Invalid size!");
return Value & ((uint64_t) (int64_t) -1 >> (64 - Bytes * 8));
}
void MCAsmStreamer::ChangeSection(const MCSection *Section,
const MCExpr *Subsection) {
assert(Section && "Cannot switch to a null section!");
Section->PrintSwitchToSection(*MAI, OS, Subsection);
}
void MCAsmStreamer::EmitEHSymAttributes(const MCSymbol *Symbol,
MCSymbol *EHSymbol) {
if (UseCFI)
return;
unsigned Flags = FlagMap.lookup(Symbol);
if (Flags & EHGlobal)
EmitSymbolAttribute(EHSymbol, MCSA_Global);
if (Flags & EHWeakDefinition)
EmitSymbolAttribute(EHSymbol, MCSA_WeakDefinition);
if (Flags & EHPrivateExtern)
EmitSymbolAttribute(EHSymbol, MCSA_PrivateExtern);
}
void MCAsmStreamer::EmitLabel(MCSymbol *Symbol) {
assert(Symbol->isUndefined() && "Cannot define a symbol twice!");
MCStreamer::EmitLabel(Symbol);
OS << *Symbol << MAI->getLabelSuffix();
EmitEOL();
}
void MCAsmStreamer::EmitDebugLabel(MCSymbol *Symbol) {
assert(Symbol->isUndefined() && "Cannot define a symbol twice!");
MCStreamer::EmitDebugLabel(Symbol);
OS << *Symbol << MAI->getDebugLabelSuffix();
EmitEOL();
}
void MCAsmStreamer::EmitAssemblerFlag(MCAssemblerFlag Flag) {
switch (Flag) {
case MCAF_SyntaxUnified: OS << "\t.syntax unified"; break;
case MCAF_SubsectionsViaSymbols: OS << ".subsections_via_symbols"; break;
case MCAF_Code16: OS << '\t'<< MAI->getCode16Directive();break;
case MCAF_Code32: OS << '\t'<< MAI->getCode32Directive();break;
case MCAF_Code64: OS << '\t'<< MAI->getCode64Directive();break;
}
EmitEOL();
}
void MCAsmStreamer::EmitLinkerOptions(ArrayRef<std::string> Options) {
assert(!Options.empty() && "At least one option is required!");
OS << "\t.linker_option \"" << Options[0] << '"';
for (ArrayRef<std::string>::iterator it = Options.begin() + 1,
ie = Options.end(); it != ie; ++it) {
OS << ", " << '"' << *it << '"';
}
OS << "\n";
}
void MCAsmStreamer::EmitDataRegion(MCDataRegionType Kind) {
if (!MAI->doesSupportDataRegionDirectives())
return;
switch (Kind) {
case MCDR_DataRegion: OS << "\t.data_region"; break;
case MCDR_DataRegionJT8: OS << "\t.data_region jt8"; break;
case MCDR_DataRegionJT16: OS << "\t.data_region jt16"; break;
case MCDR_DataRegionJT32: OS << "\t.data_region jt32"; break;
case MCDR_DataRegionEnd: OS << "\t.end_data_region"; break;
}
EmitEOL();
}
void MCAsmStreamer::EmitThumbFunc(MCSymbol *Func) {
// This needs to emit to a temporary string to get properly quoted
// MCSymbols when they have spaces in them.
OS << "\t.thumb_func";
// Only Mach-O hasSubsectionsViaSymbols()
if (MAI->hasSubsectionsViaSymbols())
OS << '\t' << *Func;
EmitEOL();
}
void MCAsmStreamer::EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) {
OS << *Symbol << " = " << *Value;
EmitEOL();
// FIXME: Lift context changes into super class.
Symbol->setVariableValue(Value);
}
void MCAsmStreamer::EmitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol) {
OS << ".weakref " << *Alias << ", " << *Symbol;
EmitEOL();
}
void MCAsmStreamer::EmitDwarfAdvanceLineAddr(int64_t LineDelta,
const MCSymbol *LastLabel,
const MCSymbol *Label,
unsigned PointerSize) {
EmitDwarfSetLineAddr(LineDelta, Label, PointerSize);
}
void MCAsmStreamer::EmitDwarfAdvanceFrameAddr(const MCSymbol *LastLabel,
const MCSymbol *Label) {
EmitIntValue(dwarf::DW_CFA_advance_loc4, 1);
const MCExpr *AddrDelta = BuildSymbolDiff(getContext(), Label, LastLabel);
AddrDelta = ForceExpAbs(AddrDelta);
EmitValue(AddrDelta, 4);
}
bool MCAsmStreamer::EmitSymbolAttribute(MCSymbol *Symbol,
MCSymbolAttr Attribute) {
switch (Attribute) {
case MCSA_Invalid: llvm_unreachable("Invalid symbol attribute");
case MCSA_ELF_TypeFunction: /// .type _foo, STT_FUNC # aka @function
case MCSA_ELF_TypeIndFunction: /// .type _foo, STT_GNU_IFUNC
case MCSA_ELF_TypeObject: /// .type _foo, STT_OBJECT # aka @object
case MCSA_ELF_TypeTLS: /// .type _foo, STT_TLS # aka @tls_object
case MCSA_ELF_TypeCommon: /// .type _foo, STT_COMMON # aka @common
case MCSA_ELF_TypeNoType: /// .type _foo, STT_NOTYPE # aka @notype
case MCSA_ELF_TypeGnuUniqueObject: /// .type _foo, @gnu_unique_object
if (!MAI->hasDotTypeDotSizeDirective())
return false; // Symbol attribute not supported
OS << "\t.type\t" << *Symbol << ','
<< ((MAI->getCommentString()[0] != '@') ? '@' : '%');
switch (Attribute) {
default: return false;
case MCSA_ELF_TypeFunction: OS << "function"; break;
case MCSA_ELF_TypeIndFunction: OS << "gnu_indirect_function"; break;
case MCSA_ELF_TypeObject: OS << "object"; break;
case MCSA_ELF_TypeTLS: OS << "tls_object"; break;
case MCSA_ELF_TypeCommon: OS << "common"; break;
case MCSA_ELF_TypeNoType: OS << "no_type"; break;
case MCSA_ELF_TypeGnuUniqueObject: OS << "gnu_unique_object"; break;
}
EmitEOL();
return true;
case MCSA_Global: // .globl/.global
OS << MAI->getGlobalDirective();
FlagMap[Symbol] |= EHGlobal;
break;
case MCSA_Hidden: OS << "\t.hidden\t"; break;
case MCSA_IndirectSymbol: OS << "\t.indirect_symbol\t"; break;
case MCSA_Internal: OS << "\t.internal\t"; break;
case MCSA_LazyReference: OS << "\t.lazy_reference\t"; break;
case MCSA_Local: OS << "\t.local\t"; break;
case MCSA_NoDeadStrip: OS << "\t.no_dead_strip\t"; break;
case MCSA_SymbolResolver: OS << "\t.symbol_resolver\t"; break;
case MCSA_PrivateExtern:
OS << "\t.private_extern\t";
FlagMap[Symbol] |= EHPrivateExtern;
break;
case MCSA_Protected: OS << "\t.protected\t"; break;
case MCSA_Reference: OS << "\t.reference\t"; break;
case MCSA_Weak: OS << "\t.weak\t"; break;
case MCSA_WeakDefinition:
OS << "\t.weak_definition\t";
FlagMap[Symbol] |= EHWeakDefinition;
break;
// .weak_reference
case MCSA_WeakReference: OS << MAI->getWeakRefDirective(); break;
case MCSA_WeakDefAutoPrivate: OS << "\t.weak_def_can_be_hidden\t"; break;
}
OS << *Symbol;
EmitEOL();
return true;
}
void MCAsmStreamer::EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) {
OS << ".desc" << ' ' << *Symbol << ',' << DescValue;
EmitEOL();
}
void MCAsmStreamer::BeginCOFFSymbolDef(const MCSymbol *Symbol) {
OS << "\t.def\t " << *Symbol << ';';
EmitEOL();
}
void MCAsmStreamer::EmitCOFFSymbolStorageClass (int StorageClass) {
OS << "\t.scl\t" << StorageClass << ';';
EmitEOL();
}
void MCAsmStreamer::EmitCOFFSymbolType (int Type) {
OS << "\t.type\t" << Type << ';';
EmitEOL();
}
void MCAsmStreamer::EndCOFFSymbolDef() {
OS << "\t.endef";
EmitEOL();
}
void MCAsmStreamer::EmitCOFFSecRel32(MCSymbol const *Symbol) {
OS << "\t.secrel32\t" << *Symbol << '\n';
EmitEOL();
}
void MCAsmStreamer::EmitELFSize(MCSymbol *Symbol, const MCExpr *Value) {
assert(MAI->hasDotTypeDotSizeDirective());
OS << "\t.size\t" << *Symbol << ", " << *Value << '\n';
}
void MCAsmStreamer::EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
unsigned ByteAlignment) {
// Common symbols do not belong to any actual section.
AssignSection(Symbol, NULL);
OS << "\t.comm\t" << *Symbol << ',' << Size;
if (ByteAlignment != 0) {
if (MAI->getCOMMDirectiveAlignmentIsInBytes())
OS << ',' << ByteAlignment;
else
OS << ',' << Log2_32(ByteAlignment);
}
EmitEOL();
}
/// EmitLocalCommonSymbol - Emit a local common (.lcomm) symbol.
///
/// @param Symbol - The common symbol to emit.
/// @param Size - The size of the common symbol.
void MCAsmStreamer::EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
unsigned ByteAlign) {
// Common symbols do not belong to any actual section.
AssignSection(Symbol, NULL);
OS << "\t.lcomm\t" << *Symbol << ',' << Size;
if (ByteAlign > 1) {
switch (MAI->getLCOMMDirectiveAlignmentType()) {
case LCOMM::NoAlignment:
llvm_unreachable("alignment not supported on .lcomm!");
case LCOMM::ByteAlignment:
OS << ',' << ByteAlign;
break;
case LCOMM::Log2Alignment:
assert(isPowerOf2_32(ByteAlign) && "alignment must be a power of 2");
OS << ',' << Log2_32(ByteAlign);
break;
}
}
EmitEOL();
}
void MCAsmStreamer::EmitZerofill(const MCSection *Section, MCSymbol *Symbol,
uint64_t Size, unsigned ByteAlignment) {
if (Symbol)
AssignSection(Symbol, Section);
// Note: a .zerofill directive does not switch sections.
OS << ".zerofill ";
// This is a mach-o specific directive.
const MCSectionMachO *MOSection = ((const MCSectionMachO*)Section);
OS << MOSection->getSegmentName() << "," << MOSection->getSectionName();
if (Symbol != NULL) {
OS << ',' << *Symbol << ',' << Size;
if (ByteAlignment != 0)
OS << ',' << Log2_32(ByteAlignment);
}
EmitEOL();
}
// .tbss sym, size, align
// This depends that the symbol has already been mangled from the original,
// e.g. _a.
void MCAsmStreamer::EmitTBSSSymbol(const MCSection *Section, MCSymbol *Symbol,
uint64_t Size, unsigned ByteAlignment) {
AssignSection(Symbol, Section);
assert(Symbol != NULL && "Symbol shouldn't be NULL!");
// Instead of using the Section we'll just use the shortcut.
// This is a mach-o specific directive and section.
OS << ".tbss " << *Symbol << ", " << Size;
// Output align if we have it. We default to 1 so don't bother printing
// that.
if (ByteAlignment > 1) OS << ", " << Log2_32(ByteAlignment);
EmitEOL();
}
static inline char toOctal(int X) { return (X&7)+'0'; }
static void PrintQuotedString(StringRef Data, raw_ostream &OS) {
OS << '"';
for (unsigned i = 0, e = Data.size(); i != e; ++i) {
unsigned char C = Data[i];
if (C == '"' || C == '\\') {
OS << '\\' << (char)C;
continue;
}
if (isprint((unsigned char)C)) {
OS << (char)C;
continue;
}
switch (C) {
case '\b': OS << "\\b"; break;
case '\f': OS << "\\f"; break;
case '\n': OS << "\\n"; break;
case '\r': OS << "\\r"; break;
case '\t': OS << "\\t"; break;
default:
OS << '\\';
OS << toOctal(C >> 6);
OS << toOctal(C >> 3);
OS << toOctal(C >> 0);
break;
}
}
OS << '"';
}
void MCAsmStreamer::EmitBytes(StringRef Data) {
assert(getCurrentSection().first &&
"Cannot emit contents before setting section!");
if (Data.empty()) return;
if (Data.size() == 1) {
OS << MAI->getData8bitsDirective();
OS << (unsigned)(unsigned char)Data[0];
EmitEOL();
return;
}
// If the data ends with 0 and the target supports .asciz, use it, otherwise
// use .ascii
if (MAI->getAscizDirective() && Data.back() == 0) {
OS << MAI->getAscizDirective();
Data = Data.substr(0, Data.size()-1);
} else {
OS << MAI->getAsciiDirective();
}
PrintQuotedString(Data, OS);
EmitEOL();
}
void MCAsmStreamer::EmitIntValue(uint64_t Value, unsigned Size) {
EmitValue(MCConstantExpr::Create(Value, getContext()), Size);
}
void MCAsmStreamer::EmitValueImpl(const MCExpr *Value, unsigned Size) {
assert(getCurrentSection().first &&
"Cannot emit contents before setting section!");
const char *Directive = 0;
switch (Size) {
default: break;
case 1: Directive = MAI->getData8bitsDirective(); break;
case 2: Directive = MAI->getData16bitsDirective(); break;
case 4: Directive = MAI->getData32bitsDirective(); break;
case 8:
Directive = MAI->getData64bitsDirective();
// If the target doesn't support 64-bit data, emit as two 32-bit halves.
if (Directive) break;
int64_t IntValue;
if (!Value->EvaluateAsAbsolute(IntValue))
report_fatal_error("Don't know how to emit this value.");
if (MAI->isLittleEndian()) {
EmitIntValue((uint32_t)(IntValue >> 0 ), 4);
EmitIntValue((uint32_t)(IntValue >> 32), 4);
} else {
EmitIntValue((uint32_t)(IntValue >> 32), 4);
EmitIntValue((uint32_t)(IntValue >> 0 ), 4);
}
return;
}
assert(Directive && "Invalid size for machine code value!");
OS << Directive << *Value;
EmitEOL();
}
void MCAsmStreamer::EmitULEB128Value(const MCExpr *Value) {
int64_t IntValue;
if (Value->EvaluateAsAbsolute(IntValue)) {
EmitULEB128IntValue(IntValue);
return;
}
assert(MAI->hasLEB128() && "Cannot print a .uleb");
OS << ".uleb128 " << *Value;
EmitEOL();
}
void MCAsmStreamer::EmitSLEB128Value(const MCExpr *Value) {
int64_t IntValue;
if (Value->EvaluateAsAbsolute(IntValue)) {
EmitSLEB128IntValue(IntValue);
return;
}
assert(MAI->hasLEB128() && "Cannot print a .sleb");
OS << ".sleb128 " << *Value;
EmitEOL();
}
void MCAsmStreamer::EmitGPRel64Value(const MCExpr *Value) {
assert(MAI->getGPRel64Directive() != 0);
OS << MAI->getGPRel64Directive() << *Value;
EmitEOL();
}
void MCAsmStreamer::EmitGPRel32Value(const MCExpr *Value) {
assert(MAI->getGPRel32Directive() != 0);
OS << MAI->getGPRel32Directive() << *Value;
EmitEOL();
}
/// EmitFill - Emit NumBytes bytes worth of the value specified by
/// FillValue. This implements directives such as '.space'.
void MCAsmStreamer::EmitFill(uint64_t NumBytes, uint8_t FillValue) {
if (NumBytes == 0) return;
if (const char *ZeroDirective = MAI->getZeroDirective()) {
OS << ZeroDirective << NumBytes;
if (FillValue != 0)
OS << ',' << (int)FillValue;
EmitEOL();
return;
}
// Emit a byte at a time.
MCStreamer::EmitFill(NumBytes, FillValue);
}
void MCAsmStreamer::EmitValueToAlignment(unsigned ByteAlignment, int64_t Value,
unsigned ValueSize,
unsigned MaxBytesToEmit) {
// Some assemblers don't support non-power of two alignments, so we always
// emit alignments as a power of two if possible.
if (isPowerOf2_32(ByteAlignment)) {
switch (ValueSize) {
default: llvm_unreachable("Invalid size for machine code value!");
case 1: OS << MAI->getAlignDirective(); break;
// FIXME: use MAI for this!
case 2: OS << ".p2alignw "; break;
case 4: OS << ".p2alignl "; break;
case 8: llvm_unreachable("Unsupported alignment size!");
}
if (MAI->getAlignmentIsInBytes())
OS << ByteAlignment;
else
OS << Log2_32(ByteAlignment);
if (Value || MaxBytesToEmit) {
OS << ", 0x";
OS.write_hex(truncateToSize(Value, ValueSize));
if (MaxBytesToEmit)
OS << ", " << MaxBytesToEmit;
}
EmitEOL();
return;
}
// Non-power of two alignment. This is not widely supported by assemblers.
// FIXME: Parameterize this based on MAI.
switch (ValueSize) {
default: llvm_unreachable("Invalid size for machine code value!");
case 1: OS << ".balign"; break;
case 2: OS << ".balignw"; break;
case 4: OS << ".balignl"; break;
case 8: llvm_unreachable("Unsupported alignment size!");
}
OS << ' ' << ByteAlignment;
OS << ", " << truncateToSize(Value, ValueSize);
if (MaxBytesToEmit)
OS << ", " << MaxBytesToEmit;
EmitEOL();
}
void MCAsmStreamer::EmitCodeAlignment(unsigned ByteAlignment,
unsigned MaxBytesToEmit) {
// Emit with a text fill value.
EmitValueToAlignment(ByteAlignment, MAI->getTextAlignFillValue(),
1, MaxBytesToEmit);
}
bool MCAsmStreamer::EmitValueToOffset(const MCExpr *Offset,
unsigned char Value) {
// FIXME: Verify that Offset is associated with the current section.
OS << ".org " << *Offset << ", " << (unsigned) Value;
EmitEOL();
return false;
}
void MCAsmStreamer::EmitFileDirective(StringRef Filename) {
assert(MAI->hasSingleParameterDotFile());
OS << "\t.file\t";
PrintQuotedString(Filename, OS);
EmitEOL();
}
bool MCAsmStreamer::EmitDwarfFileDirective(unsigned FileNo, StringRef Directory,
StringRef Filename, unsigned CUID) {
if (!UseDwarfDirectory && !Directory.empty()) {
if (sys::path::is_absolute(Filename))
return EmitDwarfFileDirective(FileNo, "", Filename, CUID);
SmallString<128> FullPathName = Directory;
sys::path::append(FullPathName, Filename);
return EmitDwarfFileDirective(FileNo, "", FullPathName, CUID);
}
if (UseLoc) {
OS << "\t.file\t" << FileNo << ' ';
if (!Directory.empty()) {
PrintQuotedString(Directory, OS);
OS << ' ';
}
PrintQuotedString(Filename, OS);
EmitEOL();
// All .file will belong to a single CUID.
CUID = 0;
}
return this->MCStreamer::EmitDwarfFileDirective(FileNo, Directory, Filename,
CUID);
}
void MCAsmStreamer::EmitDwarfLocDirective(unsigned FileNo, unsigned Line,
unsigned Column, unsigned Flags,
unsigned Isa,
unsigned Discriminator,
StringRef FileName) {
this->MCStreamer::EmitDwarfLocDirective(FileNo, Line, Column, Flags,
Isa, Discriminator, FileName);
if (!UseLoc)
return;
OS << "\t.loc\t" << FileNo << " " << Line << " " << Column;
if (Flags & DWARF2_FLAG_BASIC_BLOCK)
OS << " basic_block";
if (Flags & DWARF2_FLAG_PROLOGUE_END)
OS << " prologue_end";
if (Flags & DWARF2_FLAG_EPILOGUE_BEGIN)
OS << " epilogue_begin";
unsigned OldFlags = getContext().getCurrentDwarfLoc().getFlags();
if ((Flags & DWARF2_FLAG_IS_STMT) != (OldFlags & DWARF2_FLAG_IS_STMT)) {
OS << " is_stmt ";
if (Flags & DWARF2_FLAG_IS_STMT)
OS << "1";
else
OS << "0";
}
if (Isa)
OS << "isa " << Isa;
if (Discriminator)
OS << "discriminator " << Discriminator;
if (IsVerboseAsm) {
OS.PadToColumn(MAI->getCommentColumn());
OS << MAI->getCommentString() << ' ' << FileName << ':'
<< Line << ':' << Column;
}
EmitEOL();
}
void MCAsmStreamer::EmitIdent(StringRef IdentString) {
assert(MAI->hasIdentDirective() && ".ident directive not supported");
OS << "\t.ident\t";
PrintQuotedString(IdentString, OS);
EmitEOL();
}
void MCAsmStreamer::EmitCFISections(bool EH, bool Debug) {
MCStreamer::EmitCFISections(EH, Debug);
if (!UseCFI)
return;
OS << "\t.cfi_sections ";
if (EH) {
OS << ".eh_frame";
if (Debug)
OS << ", .debug_frame";
} else if (Debug) {
OS << ".debug_frame";
}
EmitEOL();
}
void MCAsmStreamer::EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame) {
if (!UseCFI) {
RecordProcStart(Frame);
return;
}
OS << "\t.cfi_startproc";
EmitEOL();
}
void MCAsmStreamer::EmitCFIEndProcImpl(MCDwarfFrameInfo &Frame) {
if (!UseCFI) {
RecordProcEnd(Frame);
return;
}
// Put a dummy non-null value in Frame.End to mark that this frame has been
// closed.
Frame.End = (MCSymbol *) 1;
OS << "\t.cfi_endproc";
EmitEOL();
}
void MCAsmStreamer::EmitRegisterName(int64_t Register) {
if (InstPrinter && !MAI->useDwarfRegNumForCFI()) {
const MCRegisterInfo *MRI = getContext().getRegisterInfo();
unsigned LLVMRegister = MRI->getLLVMRegNum(Register, true);
InstPrinter->printRegName(OS, LLVMRegister);
} else {
OS << Register;
}
}
void MCAsmStreamer::EmitCFIDefCfa(int64_t Register, int64_t Offset) {
MCStreamer::EmitCFIDefCfa(Register, Offset);
if (!UseCFI)
return;
OS << "\t.cfi_def_cfa ";
EmitRegisterName(Register);
OS << ", " << Offset;
EmitEOL();
}
void MCAsmStreamer::EmitCFIDefCfaOffset(int64_t Offset) {
MCStreamer::EmitCFIDefCfaOffset(Offset);
if (!UseCFI)
return;
OS << "\t.cfi_def_cfa_offset " << Offset;
EmitEOL();
}
void MCAsmStreamer::EmitCFIDefCfaRegister(int64_t Register) {
MCStreamer::EmitCFIDefCfaRegister(Register);
if (!UseCFI)
return;
OS << "\t.cfi_def_cfa_register ";
EmitRegisterName(Register);
EmitEOL();
}
void MCAsmStreamer::EmitCFIOffset(int64_t Register, int64_t Offset) {
this->MCStreamer::EmitCFIOffset(Register, Offset);
if (!UseCFI)
return;
OS << "\t.cfi_offset ";
EmitRegisterName(Register);
OS << ", " << Offset;
EmitEOL();
}
void MCAsmStreamer::EmitCFIPersonality(const MCSymbol *Sym,
unsigned Encoding) {
MCStreamer::EmitCFIPersonality(Sym, Encoding);
if (!UseCFI)
return;
OS << "\t.cfi_personality " << Encoding << ", " << *Sym;
EmitEOL();
}
void MCAsmStreamer::EmitCFILsda(const MCSymbol *Sym, unsigned Encoding) {
MCStreamer::EmitCFILsda(Sym, Encoding);
if (!UseCFI)
return;
OS << "\t.cfi_lsda " << Encoding << ", " << *Sym;
EmitEOL();
}
void MCAsmStreamer::EmitCFIRememberState() {
MCStreamer::EmitCFIRememberState();
if (!UseCFI)
return;
OS << "\t.cfi_remember_state";
EmitEOL();
}
void MCAsmStreamer::EmitCFIRestoreState() {
MCStreamer::EmitCFIRestoreState();
if (!UseCFI)
return;
OS << "\t.cfi_restore_state";
EmitEOL();
}
void MCAsmStreamer::EmitCFISameValue(int64_t Register) {
MCStreamer::EmitCFISameValue(Register);
if (!UseCFI)
return;
OS << "\t.cfi_same_value ";
EmitRegisterName(Register);
EmitEOL();
}
void MCAsmStreamer::EmitCFIRelOffset(int64_t Register, int64_t Offset) {
MCStreamer::EmitCFIRelOffset(Register, Offset);
if (!UseCFI)
return;
OS << "\t.cfi_rel_offset ";
EmitRegisterName(Register);
OS << ", " << Offset;
EmitEOL();
}
void MCAsmStreamer::EmitCFIAdjustCfaOffset(int64_t Adjustment) {
MCStreamer::EmitCFIAdjustCfaOffset(Adjustment);
if (!UseCFI)
return;
OS << "\t.cfi_adjust_cfa_offset " << Adjustment;
EmitEOL();
}
void MCAsmStreamer::EmitCFISignalFrame() {
MCStreamer::EmitCFISignalFrame();
if (!UseCFI)
return;
OS << "\t.cfi_signal_frame";
EmitEOL();
}
void MCAsmStreamer::EmitCFIUndefined(int64_t Register) {
MCStreamer::EmitCFIUndefined(Register);
if (!UseCFI)
return;
OS << "\t.cfi_undefined " << Register;
EmitEOL();
}
void MCAsmStreamer::EmitCFIRegister(int64_t Register1, int64_t Register2) {
MCStreamer::EmitCFIRegister(Register1, Register2);
if (!UseCFI)
return;
OS << "\t.cfi_register " << Register1 << ", " << Register2;
EmitEOL();
}
void MCAsmStreamer::EmitCFIWindowSave() {
MCStreamer::EmitCFIWindowSave();
if (!UseCFI)
return;
OS << "\t.cfi_window_save";
EmitEOL();
}
void MCAsmStreamer::EmitWin64EHStartProc(const MCSymbol *Symbol) {
MCStreamer::EmitWin64EHStartProc(Symbol);
OS << ".seh_proc " << *Symbol;
EmitEOL();
}
void MCAsmStreamer::EmitWin64EHEndProc() {
MCStreamer::EmitWin64EHEndProc();
OS << "\t.seh_endproc";
EmitEOL();
}
void MCAsmStreamer::EmitWin64EHStartChained() {
MCStreamer::EmitWin64EHStartChained();
OS << "\t.seh_startchained";
EmitEOL();
}
void MCAsmStreamer::EmitWin64EHEndChained() {
MCStreamer::EmitWin64EHEndChained();
OS << "\t.seh_endchained";
EmitEOL();
}
void MCAsmStreamer::EmitWin64EHHandler(const MCSymbol *Sym, bool Unwind,
bool Except) {
MCStreamer::EmitWin64EHHandler(Sym, Unwind, Except);
OS << "\t.seh_handler " << *Sym;
if (Unwind)
OS << ", @unwind";
if (Except)
OS << ", @except";
EmitEOL();
}
static const MCSection *getWin64EHTableSection(StringRef suffix,
MCContext &context) {
// FIXME: This doesn't belong in MCObjectFileInfo. However,
/// this duplicate code in MCWin64EH.cpp.
if (suffix == "")
return context.getObjectFileInfo()->getXDataSection();
return context.getCOFFSection((".xdata"+suffix).str(),
COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
COFF::IMAGE_SCN_MEM_READ |
COFF::IMAGE_SCN_MEM_WRITE,
SectionKind::getDataRel());
}
void MCAsmStreamer::EmitWin64EHHandlerData() {
MCStreamer::EmitWin64EHHandlerData();
// Switch sections. Don't call SwitchSection directly, because that will
// cause the section switch to be visible in the emitted assembly.
// We only do this so the section switch that terminates the handler
// data block is visible.
MCWin64EHUnwindInfo *CurFrame = getCurrentW64UnwindInfo();
StringRef suffix=MCWin64EHUnwindEmitter::GetSectionSuffix(CurFrame->Function);
const MCSection *xdataSect = getWin64EHTableSection(suffix, getContext());
if (xdataSect)
SwitchSectionNoChange(xdataSect);
OS << "\t.seh_handlerdata";
EmitEOL();
}
void MCAsmStreamer::EmitWin64EHPushReg(unsigned Register) {
MCStreamer::EmitWin64EHPushReg(Register);
OS << "\t.seh_pushreg " << Register;
EmitEOL();
}
void MCAsmStreamer::EmitWin64EHSetFrame(unsigned Register, unsigned Offset) {
MCStreamer::EmitWin64EHSetFrame(Register, Offset);
OS << "\t.seh_setframe " << Register << ", " << Offset;
EmitEOL();
}
void MCAsmStreamer::EmitWin64EHAllocStack(unsigned Size) {
MCStreamer::EmitWin64EHAllocStack(Size);
OS << "\t.seh_stackalloc " << Size;
EmitEOL();
}
void MCAsmStreamer::EmitWin64EHSaveReg(unsigned Register, unsigned Offset) {
MCStreamer::EmitWin64EHSaveReg(Register, Offset);
OS << "\t.seh_savereg " << Register << ", " << Offset;
EmitEOL();
}
void MCAsmStreamer::EmitWin64EHSaveXMM(unsigned Register, unsigned Offset) {
MCStreamer::EmitWin64EHSaveXMM(Register, Offset);
OS << "\t.seh_savexmm " << Register << ", " << Offset;
EmitEOL();
}
void MCAsmStreamer::EmitWin64EHPushFrame(bool Code) {
MCStreamer::EmitWin64EHPushFrame(Code);
OS << "\t.seh_pushframe";
if (Code)
OS << " @code";
EmitEOL();
}
void MCAsmStreamer::EmitWin64EHEndProlog(void) {
MCStreamer::EmitWin64EHEndProlog();
OS << "\t.seh_endprologue";
EmitEOL();
}
void MCAsmStreamer::AddEncodingComment(const MCInst &Inst) {
raw_ostream &OS = GetCommentOS();
SmallString<256> Code;
SmallVector<MCFixup, 4> Fixups;
raw_svector_ostream VecOS(Code);
Emitter->EncodeInstruction(Inst, VecOS, Fixups);
VecOS.flush();
// If we are showing fixups, create symbolic markers in the encoded
// representation. We do this by making a per-bit map to the fixup item index,
// then trying to display it as nicely as possible.
SmallVector<uint8_t, 64> FixupMap;
FixupMap.resize(Code.size() * 8);
for (unsigned i = 0, e = Code.size() * 8; i != e; ++i)
FixupMap[i] = 0;
for (unsigned i = 0, e = Fixups.size(); i != e; ++i) {
MCFixup &F = Fixups[i];
const MCFixupKindInfo &Info = AsmBackend->getFixupKindInfo(F.getKind());
for (unsigned j = 0; j != Info.TargetSize; ++j) {
unsigned Index = F.getOffset() * 8 + Info.TargetOffset + j;
assert(Index < Code.size() * 8 && "Invalid offset in fixup!");
FixupMap[Index] = 1 + i;
}
}
// FIXME: Note the fixup comments for Thumb2 are completely bogus since the
// high order halfword of a 32-bit Thumb2 instruction is emitted first.
OS << "encoding: [";
for (unsigned i = 0, e = Code.size(); i != e; ++i) {
if (i)
OS << ',';
// See if all bits are the same map entry.
uint8_t MapEntry = FixupMap[i * 8 + 0];
for (unsigned j = 1; j != 8; ++j) {
if (FixupMap[i * 8 + j] == MapEntry)
continue;
MapEntry = uint8_t(~0U);
break;
}
if (MapEntry != uint8_t(~0U)) {
if (MapEntry == 0) {
OS << format("0x%02x", uint8_t(Code[i]));
} else {
if (Code[i]) {
// FIXME: Some of the 8 bits require fix up.
OS << format("0x%02x", uint8_t(Code[i])) << '\''
<< char('A' + MapEntry - 1) << '\'';
} else
OS << char('A' + MapEntry - 1);
}
} else {
// Otherwise, write out in binary.
OS << "0b";
for (unsigned j = 8; j--;) {
unsigned Bit = (Code[i] >> j) & 1;
unsigned FixupBit;
if (MAI->isLittleEndian())
FixupBit = i * 8 + j;
else
FixupBit = i * 8 + (7-j);
if (uint8_t MapEntry = FixupMap[FixupBit]) {
assert(Bit == 0 && "Encoder wrote into fixed up bit!");
OS << char('A' + MapEntry - 1);
} else
OS << Bit;
}
}
}
OS << "]\n";
for (unsigned i = 0, e = Fixups.size(); i != e; ++i) {
MCFixup &F = Fixups[i];
const MCFixupKindInfo &Info = AsmBackend->getFixupKindInfo(F.getKind());
OS << " fixup " << char('A' + i) << " - " << "offset: " << F.getOffset()
<< ", value: " << *F.getValue() << ", kind: " << Info.Name << "\n";
}
}
void MCAsmStreamer::EmitInstruction(const MCInst &Inst) {
assert(getCurrentSection().first &&
"Cannot emit contents before setting section!");
// Show the encoding in a comment if we have a code emitter.
if (Emitter)
AddEncodingComment(Inst);
// Show the MCInst if enabled.
if (ShowInst) {
Inst.dump_pretty(GetCommentOS(), MAI, InstPrinter.get(), "\n ");
GetCommentOS() << "\n";
}
// If we have an AsmPrinter, use that to print, otherwise print the MCInst.
if (InstPrinter)
InstPrinter->printInst(&Inst, OS, "");
else
Inst.print(OS, MAI);
EmitEOL();
}
void MCAsmStreamer::EmitBundleAlignMode(unsigned AlignPow2) {
OS << "\t.bundle_align_mode " << AlignPow2;
EmitEOL();
}
void MCAsmStreamer::EmitBundleLock(bool AlignToEnd) {
OS << "\t.bundle_lock";
if (AlignToEnd)
OS << " align_to_end";
EmitEOL();
}
void MCAsmStreamer::EmitBundleUnlock() {
OS << "\t.bundle_unlock";
EmitEOL();
}
/// EmitRawText - If this file is backed by an assembly streamer, this dumps
/// the specified string in the output .s file. This capability is
/// indicated by the hasRawTextSupport() predicate.
void MCAsmStreamer::EmitRawTextImpl(StringRef String) {
if (!String.empty() && String.back() == '\n')
String = String.substr(0, String.size()-1);
OS << String;
EmitEOL();
}
void MCAsmStreamer::FinishImpl() {
// FIXME: This header is duplicated with MCObjectStreamer
// Dump out the dwarf file & directory tables and line tables.
const MCSymbol *LineSectionSymbol = NULL;
if (getContext().hasDwarfFiles() && !UseLoc)
LineSectionSymbol = MCDwarfFileTable::Emit(this);
// If we are generating dwarf for assembly source files dump out the sections.
if (getContext().getGenDwarfForAssembly())
MCGenDwarfInfo::Emit(this, LineSectionSymbol);
if (!UseCFI)
EmitFrames(AsmBackend.get(), false);
}
MCStreamer *llvm::createAsmStreamer(MCContext &Context,
MCTargetStreamer *TargetStreamer,
formatted_raw_ostream &OS,
bool isVerboseAsm, bool useLoc, bool useCFI,
bool useDwarfDirectory, MCInstPrinter *IP,
MCCodeEmitter *CE, MCAsmBackend *MAB,
bool ShowInst) {
return new MCAsmStreamer(Context, TargetStreamer, OS, isVerboseAsm, useLoc,
useCFI, useDwarfDirectory, IP, CE, MAB, ShowInst);
}
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