//===-- llvm/MC/MCAsmInfo.h - Asm info --------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains a class to be used as the basis for target specific
// asm writers. This class primarily takes care of global printing constants,
// which are used in very similar ways across all targets.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_TARGET_ASM_INFO_H
#define LLVM_TARGET_ASM_INFO_H
#include "llvm/MC/MachineLocation.h"
#include "llvm/MC/MCDirectives.h"
#include <cassert>
#include <vector>
namespace llvm {
class MCExpr;
class MCSection;
class MCStreamer;
class MCSymbol;
class MCContext;
namespace ExceptionHandling {
enum ExceptionsType { None, DwarfCFI, SjLj, ARM, Win64 };
}
namespace LCOMM {
enum LCOMMType { None, NoAlignment, ByteAlignment };
}
namespace Structors {
enum OutputOrder { None, PriorityOrder, ReversePriorityOrder };
}
/// MCAsmInfo - This class is intended to be used as a base class for asm
/// properties and features specific to the target.
class MCAsmInfo {
protected:
//===------------------------------------------------------------------===//
// Properties to be set by the target writer, used to configure asm printer.
//
/// PointerSize - Pointer size in bytes.
/// Default is 4.
unsigned PointerSize;
/// IsLittleEndian - True if target is little endian.
/// Default is true.
bool IsLittleEndian;
/// StackGrowsUp - True if target stack grow up.
/// Default is false.
bool StackGrowsUp;
/// HasSubsectionsViaSymbols - True if this target has the MachO
/// .subsections_via_symbols directive.
bool HasSubsectionsViaSymbols; // Default is false.
/// HasMachoZeroFillDirective - True if this is a MachO target that supports
/// the macho-specific .zerofill directive for emitting BSS Symbols.
bool HasMachoZeroFillDirective; // Default is false.
/// HasMachoTBSSDirective - True if this is a MachO target that supports
/// the macho-specific .tbss directive for emitting thread local BSS Symbols
bool HasMachoTBSSDirective; // Default is false.
/// StructorOutputOrder - Whether the static ctor/dtor list should be output
/// in no particular order, in order of increasing priority or the reverse:
/// in order of decreasing priority (the default).
Structors::OutputOrder StructorOutputOrder; // Default is reverse order.
/// HasStaticCtorDtorReferenceInStaticMode - True if the compiler should
/// emit a ".reference .constructors_used" or ".reference .destructors_used"
/// directive after the a static ctor/dtor list. This directive is only
/// emitted in Static relocation model.
bool HasStaticCtorDtorReferenceInStaticMode; // Default is false.
/// LinkerRequiresNonEmptyDwarfLines - True if the linker has a bug and
/// requires that the debug_line section be of a minimum size. In practice
/// such a linker requires a non empty line sequence if a file is present.
bool LinkerRequiresNonEmptyDwarfLines; // Default to false.
/// MaxInstLength - This is the maximum possible length of an instruction,
/// which is needed to compute the size of an inline asm.
unsigned MaxInstLength; // Defaults to 4.
/// PCSymbol - The symbol used to represent the current PC. Used in PC
/// relative expressions.
const char *PCSymbol; // Defaults to "$".
/// SeparatorString - This string, if specified, is used to separate
/// instructions from each other when on the same line.
const char *SeparatorString; // Defaults to ';'
/// CommentColumn - This indicates the comment num (zero-based) at
/// which asm comments should be printed.
unsigned CommentColumn; // Defaults to 40
/// CommentString - This indicates the comment character used by the
/// assembler.
const char *CommentString; // Defaults to "#"
/// LabelSuffix - This is appended to emitted labels.
const char *LabelSuffix; // Defaults to ":"
/// GlobalPrefix - If this is set to a non-empty string, it is prepended
/// onto all global symbols. This is often used for "_" or ".".
const char *GlobalPrefix; // Defaults to ""
/// PrivateGlobalPrefix - This prefix is used for globals like constant
/// pool entries that are completely private to the .s file and should not
/// have names in the .o file. This is often "." or "L".
const char *PrivateGlobalPrefix; // Defaults to "."
/// LinkerPrivateGlobalPrefix - This prefix is used for symbols that should
/// be passed through the assembler but be removed by the linker. This
/// is "l" on Darwin, currently used for some ObjC metadata.
const char *LinkerPrivateGlobalPrefix; // Defaults to ""
/// InlineAsmStart/End - If these are nonempty, they contain a directive to
/// emit before and after an inline assembly statement.
const char *InlineAsmStart; // Defaults to "#APP\n"
const char *InlineAsmEnd; // Defaults to "#NO_APP\n"
/// Code16Directive, Code32Directive, Code64Directive - These are assembly
/// directives that tells the assembler to interpret the following
/// instructions differently.
const char *Code16Directive; // Defaults to ".code16"
const char *Code32Directive; // Defaults to ".code32"
const char *Code64Directive; // Defaults to ".code64"
/// AssemblerDialect - Which dialect of an assembler variant to use.
unsigned AssemblerDialect; // Defaults to 0
/// AllowQuotesInName - This is true if the assembler allows for complex
/// symbol names to be surrounded in quotes. This defaults to false.
bool AllowQuotesInName;
/// AllowNameToStartWithDigit - This is true if the assembler allows symbol
/// names to start with a digit (e.g., "0x0021"). This defaults to false.
bool AllowNameToStartWithDigit;
/// AllowPeriodsInName - This is true if the assembler allows periods in
/// symbol names. This defaults to true.
bool AllowPeriodsInName;
//===--- Data Emission Directives -------------------------------------===//
/// ZeroDirective - this should be set to the directive used to get some
/// number of zero bytes emitted to the current section. Common cases are
/// "\t.zero\t" and "\t.space\t". If this is set to null, the
/// Data*bitsDirective's will be used to emit zero bytes.
const char *ZeroDirective; // Defaults to "\t.zero\t"
/// AsciiDirective - This directive allows emission of an ascii string with
/// the standard C escape characters embedded into it.
const char *AsciiDirective; // Defaults to "\t.ascii\t"
/// AscizDirective - If not null, this allows for special handling of
/// zero terminated strings on this target. This is commonly supported as
/// ".asciz". If a target doesn't support this, it can be set to null.
const char *AscizDirective; // Defaults to "\t.asciz\t"
/// DataDirectives - These directives are used to output some unit of
/// integer data to the current section. If a data directive is set to
/// null, smaller data directives will be used to emit the large sizes.
const char *Data8bitsDirective; // Defaults to "\t.byte\t"
const char *Data16bitsDirective; // Defaults to "\t.short\t"
const char *Data32bitsDirective; // Defaults to "\t.long\t"
const char *Data64bitsDirective; // Defaults to "\t.quad\t"
/// [Data|Code]Begin - These magic labels are used to marked a region as
/// data or code, and are used to provide additional information for
/// correct disassembly on targets that like to mix data and code within
/// a segment. These labels will be implicitly suffixed by the streamer
/// to give them unique names.
const char *DataBegin; // Defaults to "$d."
const char *CodeBegin; // Defaults to "$a."
const char *JT8Begin; // Defaults to "$a."
const char *JT16Begin; // Defaults to "$a."
const char *JT32Begin; // Defaults to "$a."
bool SupportsDataRegions;
/// GPRel32Directive - if non-null, a directive that is used to emit a word
/// which should be relocated as a 32-bit GP-relative offset, e.g. .gpword
/// on Mips or .gprel32 on Alpha.
const char *GPRel32Directive; // Defaults to NULL.
/// getDataASDirective - Return the directive that should be used to emit
/// data of the specified size to the specified numeric address space.
virtual const char *getDataASDirective(unsigned Size, unsigned AS) const {
assert(AS != 0 && "Don't know the directives for default addr space");
return 0;
}
/// SunStyleELFSectionSwitchSyntax - This is true if this target uses "Sun
/// Style" syntax for section switching ("#alloc,#write" etc) instead of the
/// normal ELF syntax (,"a,w") in .section directives.
bool SunStyleELFSectionSwitchSyntax; // Defaults to false.
/// UsesELFSectionDirectiveForBSS - This is true if this target uses ELF
/// '.section' directive before the '.bss' one. It's used for PPC/Linux
/// which doesn't support the '.bss' directive only.
bool UsesELFSectionDirectiveForBSS; // Defaults to false.
/// HasMicrosoftFastStdCallMangling - True if this target uses microsoft
/// style mangling for functions with X86_StdCall/X86_FastCall calling
/// convention.
bool HasMicrosoftFastStdCallMangling; // Defaults to false.
//===--- Alignment Information ----------------------------------------===//
/// AlignDirective - The directive used to emit round up to an alignment
/// boundary.
///
const char *AlignDirective; // Defaults to "\t.align\t"
/// AlignmentIsInBytes - If this is true (the default) then the asmprinter
/// emits ".align N" directives, where N is the number of bytes to align to.
/// Otherwise, it emits ".align log2(N)", e.g. 3 to align to an 8 byte
/// boundary.
bool AlignmentIsInBytes; // Defaults to true
/// TextAlignFillValue - If non-zero, this is used to fill the executable
/// space created as the result of a alignment directive.
unsigned TextAlignFillValue; // Defaults to 0
//===--- Global Variable Emission Directives --------------------------===//
/// GlobalDirective - This is the directive used to declare a global entity.
///
const char *GlobalDirective; // Defaults to NULL.
/// ExternDirective - This is the directive used to declare external
/// globals.
///
const char *ExternDirective; // Defaults to NULL.
/// HasSetDirective - True if the assembler supports the .set directive.
bool HasSetDirective; // Defaults to true.
/// HasAggressiveSymbolFolding - False if the assembler requires that we use
/// Lc = a - b
/// .long Lc
/// instead of
/// .long a - b
bool HasAggressiveSymbolFolding; // Defaults to true.
/// LCOMMDirectiveType - Describes if the target supports the .lcomm
/// directive and whether it has an alignment parameter.
LCOMM::LCOMMType LCOMMDirectiveType; // Defaults to LCOMM::None.
/// COMMDirectiveAlignmentIsInBytes - True is COMMDirective's optional
/// alignment is to be specified in bytes instead of log2(n).
bool COMMDirectiveAlignmentIsInBytes; // Defaults to true;
/// HasDotTypeDotSizeDirective - True if the target has .type and .size
/// directives, this is true for most ELF targets.
bool HasDotTypeDotSizeDirective; // Defaults to true.
/// HasSingleParameterDotFile - True if the target has a single parameter
/// .file directive, this is true for ELF targets.
bool HasSingleParameterDotFile; // Defaults to true.
/// HasNoDeadStrip - True if this target supports the MachO .no_dead_strip
/// directive.
bool HasNoDeadStrip; // Defaults to false.
/// HasSymbolResolver - True if this target supports the MachO
/// .symbol_resolver directive.
bool HasSymbolResolver; // Defaults to false.
/// WeakRefDirective - This directive, if non-null, is used to declare a
/// global as being a weak undefined symbol.
const char *WeakRefDirective; // Defaults to NULL.
/// WeakDefDirective - This directive, if non-null, is used to declare a
/// global as being a weak defined symbol.
const char *WeakDefDirective; // Defaults to NULL.
/// LinkOnceDirective - This directive, if non-null is used to declare a
/// global as being a weak defined symbol. This is used on cygwin/mingw.
const char *LinkOnceDirective; // Defaults to NULL.
/// HiddenVisibilityAttr - This attribute, if not MCSA_Invalid, is used to
/// declare a symbol as having hidden visibility.
MCSymbolAttr HiddenVisibilityAttr; // Defaults to MCSA_Hidden.
/// HiddenDeclarationVisibilityAttr - This attribute, if not MCSA_Invalid,
/// is used to declare an undefined symbol as having hidden visibility.
MCSymbolAttr HiddenDeclarationVisibilityAttr; // Defaults to MCSA_Hidden.
/// ProtectedVisibilityAttr - This attribute, if not MCSA_Invalid, is used
/// to declare a symbol as having protected visibility.
MCSymbolAttr ProtectedVisibilityAttr; // Defaults to MCSA_Protected
//===--- Dwarf Emission Directives -----------------------------------===//
/// HasLEB128 - True if target asm supports leb128 directives.
bool HasLEB128; // Defaults to false.
/// SupportsDebugInformation - True if target supports emission of debugging
/// information.
bool SupportsDebugInformation; // Defaults to false.
/// SupportsExceptionHandling - True if target supports exception handling.
ExceptionHandling::ExceptionsType ExceptionsType; // Defaults to None
/// DwarfUsesInlineInfoSection - True if DwarfDebugInlineSection is used to
/// encode inline subroutine information.
bool DwarfUsesInlineInfoSection; // Defaults to false.
/// DwarfSectionOffsetDirective - Special section offset directive.
const char* DwarfSectionOffsetDirective; // Defaults to NULL
/// DwarfRequiresRelocationForSectionOffset - True if we need to produce a
// relocation when we want a section offset in dwarf.
bool DwarfRequiresRelocationForSectionOffset; // Defaults to true;
// DwarfUsesLabelOffsetDifference - True if Dwarf2 output can
// use EmitLabelOffsetDifference.
bool DwarfUsesLabelOffsetForRanges;
/// DwarfRegNumForCFI - True if dwarf register numbers are printed
/// instead of symbolic register names in .cfi_* directives.
bool DwarfRegNumForCFI; // Defaults to false;
//===--- CBE Asm Translation Table -----------------------------------===//
const char *const *AsmTransCBE; // Defaults to empty
//===--- Prologue State ----------------------------------------------===//
std::vector<MachineMove> InitialFrameState;
public:
explicit MCAsmInfo();
virtual ~MCAsmInfo();
// FIXME: move these methods to DwarfPrinter when the JIT stops using them.
static unsigned getSLEB128Size(int Value);
static unsigned getULEB128Size(unsigned Value);
/// getPointerSize - Get the pointer size in bytes.
unsigned getPointerSize() const {
return PointerSize;
}
/// islittleendian - True if the target is little endian.
bool isLittleEndian() const {
return IsLittleEndian;
}
/// isStackGrowthDirectionUp - True if target stack grow up.
bool isStackGrowthDirectionUp() const {
return StackGrowsUp;
}
bool hasSubsectionsViaSymbols() const { return HasSubsectionsViaSymbols; }
// Data directive accessors.
//
const char *getData8bitsDirective(unsigned AS = 0) const {
return AS == 0 ? Data8bitsDirective : getDataASDirective(8, AS);
}
const char *getData16bitsDirective(unsigned AS = 0) const {
return AS == 0 ? Data16bitsDirective : getDataASDirective(16, AS);
}
const char *getData32bitsDirective(unsigned AS = 0) const {
return AS == 0 ? Data32bitsDirective : getDataASDirective(32, AS);
}
const char *getData64bitsDirective(unsigned AS = 0) const {
return AS == 0 ? Data64bitsDirective : getDataASDirective(64, AS);
}
const char *getGPRel32Directive() const { return GPRel32Directive; }
/// [Code|Data]Begin label name accessors.
const char *getCodeBeginLabelName() const { return CodeBegin; }
const char *getDataBeginLabelName() const { return DataBegin; }
const char *getJumpTable8BeginLabelName() const { return JT8Begin; }
const char *getJumpTable16BeginLabelName() const { return JT16Begin; }
const char *getJumpTable32BeginLabelName() const { return JT32Begin; }
bool getSupportsDataRegions() const { return SupportsDataRegions; }
/// getNonexecutableStackSection - Targets can implement this method to
/// specify a section to switch to if the translation unit doesn't have any
/// trampolines that require an executable stack.
virtual const MCSection *getNonexecutableStackSection(MCContext &Ctx) const{
return 0;
}
virtual const MCExpr *
getExprForPersonalitySymbol(const MCSymbol *Sym,
unsigned Encoding,
MCStreamer &Streamer) const;
const MCExpr *
getExprForFDESymbol(const MCSymbol *Sym,
unsigned Encoding,
MCStreamer &Streamer) const;
bool usesSunStyleELFSectionSwitchSyntax() const {
return SunStyleELFSectionSwitchSyntax;
}
bool usesELFSectionDirectiveForBSS() const {
return UsesELFSectionDirectiveForBSS;
}
bool hasMicrosoftFastStdCallMangling() const {
return HasMicrosoftFastStdCallMangling;
}
// Accessors.
//
bool hasMachoZeroFillDirective() const { return HasMachoZeroFillDirective; }
bool hasMachoTBSSDirective() const { return HasMachoTBSSDirective; }
Structors::OutputOrder getStructorOutputOrder() const {
return StructorOutputOrder;
}
bool hasStaticCtorDtorReferenceInStaticMode() const {
return HasStaticCtorDtorReferenceInStaticMode;
}
bool getLinkerRequiresNonEmptyDwarfLines() const {
return LinkerRequiresNonEmptyDwarfLines;
}
unsigned getMaxInstLength() const {
return MaxInstLength;
}
const char *getPCSymbol() const {
return PCSymbol;
}
const char *getSeparatorString() const {
return SeparatorString;
}
unsigned getCommentColumn() const {
return CommentColumn;
}
const char *getCommentString() const {
return CommentString;
}
const char *getLabelSuffix() const {
return LabelSuffix;
}
const char *getGlobalPrefix() const {
return GlobalPrefix;
}
const char *getPrivateGlobalPrefix() const {
return PrivateGlobalPrefix;
}
const char *getLinkerPrivateGlobalPrefix() const {
return LinkerPrivateGlobalPrefix;
}
const char *getInlineAsmStart() const {
return InlineAsmStart;
}
const char *getInlineAsmEnd() const {
return InlineAsmEnd;
}
const char *getCode16Directive() const {
return Code16Directive;
}
const char *getCode32Directive() const {
return Code32Directive;
}
const char *getCode64Directive() const {
return Code64Directive;
}
unsigned getAssemblerDialect() const {
return AssemblerDialect;
}
bool doesAllowQuotesInName() const {
return AllowQuotesInName;
}
bool doesAllowNameToStartWithDigit() const {
return AllowNameToStartWithDigit;
}
bool doesAllowPeriodsInName() const {
return AllowPeriodsInName;
}
const char *getZeroDirective() const {
return ZeroDirective;
}
const char *getAsciiDirective() const {
return AsciiDirective;
}
const char *getAscizDirective() const {
return AscizDirective;
}
const char *getAlignDirective() const {
return AlignDirective;
}
bool getAlignmentIsInBytes() const {
return AlignmentIsInBytes;
}
unsigned getTextAlignFillValue() const {
return TextAlignFillValue;
}
const char *getGlobalDirective() const {
return GlobalDirective;
}
const char *getExternDirective() const {
return ExternDirective;
}
bool hasSetDirective() const { return HasSetDirective; }
bool hasAggressiveSymbolFolding() const {
return HasAggressiveSymbolFolding;
}
LCOMM::LCOMMType getLCOMMDirectiveType() const {
return LCOMMDirectiveType;
}
bool hasDotTypeDotSizeDirective() const {return HasDotTypeDotSizeDirective;}
bool getCOMMDirectiveAlignmentIsInBytes() const {
return COMMDirectiveAlignmentIsInBytes;
}
bool hasSingleParameterDotFile() const { return HasSingleParameterDotFile; }
bool hasNoDeadStrip() const { return HasNoDeadStrip; }
bool hasSymbolResolver() const { return HasSymbolResolver; }
const char *getWeakRefDirective() const { return WeakRefDirective; }
const char *getWeakDefDirective() const { return WeakDefDirective; }
const char *getLinkOnceDirective() const { return LinkOnceDirective; }
MCSymbolAttr getHiddenVisibilityAttr() const { return HiddenVisibilityAttr;}
MCSymbolAttr getHiddenDeclarationVisibilityAttr() const {
return HiddenDeclarationVisibilityAttr;
}
MCSymbolAttr getProtectedVisibilityAttr() const {
return ProtectedVisibilityAttr;
}
bool hasLEB128() const {
return HasLEB128;
}
bool doesSupportDebugInformation() const {
return SupportsDebugInformation;
}
bool doesSupportExceptionHandling() const {
return ExceptionsType != ExceptionHandling::None;
}
ExceptionHandling::ExceptionsType getExceptionHandlingType() const {
return ExceptionsType;
}
bool isExceptionHandlingDwarf() const {
return
(ExceptionsType == ExceptionHandling::DwarfCFI ||
ExceptionsType == ExceptionHandling::ARM ||
ExceptionsType == ExceptionHandling::Win64);
}
bool doesDwarfUsesInlineInfoSection() const {
return DwarfUsesInlineInfoSection;
}
const char *getDwarfSectionOffsetDirective() const {
return DwarfSectionOffsetDirective;
}
bool doesDwarfRequireRelocationForSectionOffset() const {
return DwarfRequiresRelocationForSectionOffset;
}
bool doesDwarfUsesLabelOffsetForRanges() const {
return DwarfUsesLabelOffsetForRanges;
}
bool useDwarfRegNumForCFI() const {
return DwarfRegNumForCFI;
}
const char *const *getAsmCBE() const {
return AsmTransCBE;
}
void addInitialFrameState(MCSymbol *label, const MachineLocation &D,
const MachineLocation &S) {
InitialFrameState.push_back(MachineMove(label, D, S));
}
const std::vector<MachineMove> &getInitialFrameState() const {
return InitialFrameState;
}
};
}
#endif