llvm-6502/include/llvm/MC/MCAsmInfo.h
David Majnemer 3f22cc1df6 MC: Add support for treating $ as a reference to the PC
The binutils assembler supports a mode called DOLLAR_DOT which treats
the dollar sign token as a reference to the current program counter if
the dollar sign doesn't precede a constant or identifier.

This commit adds a new MCAsmInfo flag stating whether or not a given
target supports this interpretation of the dollar sign token; by
default, this flag is not enabled.

Further, enable this flag for PPC. The system assembler for AIX and
binutils both support using the dollar sign in this manner.

This fixes PR17353.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191368 91177308-0d34-0410-b5e6-96231b3b80d8
2013-09-25 10:47:21 +00:00

575 lines
22 KiB
C++

//===-- 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_MC_MCASMINFO_H
#define LLVM_MC_MCASMINFO_H
#include "llvm/MC/MCDirectives.h"
#include "llvm/MC/MCDwarf.h"
#include "llvm/MC/MachineLocation.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 { NoAlignment, ByteAlignment, Log2Alignment };
}
/// 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;
/// CalleeSaveStackSlotSize - Size of the stack slot reserved for
/// callee-saved registers, in bytes.
/// Default is same as pointer size.
unsigned CalleeSaveStackSlotSize;
/// 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.
/// 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.
/// MinInstAlignment - Every possible instruction length is a multiple of
/// this value. Factored out in .debug_frame and .debug_line.
unsigned MinInstAlignment; // Defaults to 1.
/// DollarIsPC - The '$' token, when not referencing an identifier or
/// constant, refers to the current PC.
bool DollarIsPC; // Defaults to false.
/// 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 ":"
/// LabelSuffix - This is appended to emitted labels.
const char *DebugLabelSuffix; // 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;
/// AllowUTF8 - This is true if the assembler accepts UTF-8 input.
// FIXME: Make this a more general encoding setting?
bool AllowUTF8;
/// UseDataRegionDirectives - This is true if data region markers should
/// be printed as ".data_region/.end_data_region" directives. If false,
/// use "$d/$a" labels instead.
bool UseDataRegionDirectives;
//===--- 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"
/// GPRel64Directive - if non-null, a directive that is used to emit a word
/// which should be relocated as a 64-bit GP-relative offset, e.g. .gpdword
/// on Mips.
const char *GPRel64Directive; // Defaults to NULL.
/// 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.
/// 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.
bool NeedsDwarfSectionOffsetDirective;
//===--- 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.
/// COMMDirectiveAlignmentIsInBytes - True is .comm's and .lcomms optional
/// alignment is to be specified in bytes instead of log2(n).
bool COMMDirectiveAlignmentIsInBytes; // Defaults to true;
/// LCOMMDirectiveAlignment - Describes if the .lcomm directive for the
/// target supports an alignment argument and how it is interpreted.
LCOMM::LCOMMType LCOMMDirectiveAlignmentType; // Defaults to NoAlignment.
/// 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
/// DwarfUsesRelocationsAcrossSections - True if Dwarf2 output generally
/// uses relocations for references to other .debug_* sections.
bool DwarfUsesRelocationsAcrossSections;
/// DwarfRegNumForCFI - True if dwarf register numbers are printed
/// instead of symbolic register names in .cfi_* directives.
bool DwarfRegNumForCFI; // Defaults to false;
//===--- Prologue State ----------------------------------------------===//
std::vector<MCCFIInstruction> InitialFrameState;
public:
explicit MCAsmInfo();
virtual ~MCAsmInfo();
// FIXME: move these methods to DwarfPrinter when the JIT stops using them.
static unsigned getSLEB128Size(int64_t Value);
static unsigned getULEB128Size(uint64_t Value);
/// getPointerSize - Get the pointer size in bytes.
unsigned getPointerSize() const {
return PointerSize;
}
/// getCalleeSaveStackSlotSize - Get the callee-saved register stack slot
/// size in bytes.
unsigned getCalleeSaveStackSlotSize() const {
return CalleeSaveStackSlotSize;
}
/// 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() const {
return Data8bitsDirective;
}
const char *getData16bitsDirective() const {
return Data16bitsDirective;
}
const char *getData32bitsDirective() const {
return Data32bitsDirective;
}
const char *getData64bitsDirective() const {
return Data64bitsDirective;
}
const char *getGPRel64Directive() const { return GPRel64Directive; }
const char *getGPRel32Directive() const { return GPRel32Directive; }
/// 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;
}
bool needsDwarfSectionOffsetDirective() const {
return NeedsDwarfSectionOffsetDirective;
}
// Accessors.
//
bool hasMachoZeroFillDirective() const { return HasMachoZeroFillDirective; }
bool hasMachoTBSSDirective() const { return HasMachoTBSSDirective; }
bool hasStaticCtorDtorReferenceInStaticMode() const {
return HasStaticCtorDtorReferenceInStaticMode;
}
bool getLinkerRequiresNonEmptyDwarfLines() const {
return LinkerRequiresNonEmptyDwarfLines;
}
unsigned getMaxInstLength() const {
return MaxInstLength;
}
unsigned getMinInstAlignment() const {
return MinInstAlignment;
}
bool getDollarIsPC() const {
return DollarIsPC;
}
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 *getDebugLabelSuffix() const {
return DebugLabelSuffix;
}
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;
}
bool doesAllowUTF8() const {
return AllowUTF8;
}
bool doesSupportDataRegionDirectives() const {
return UseDataRegionDirectives;
}
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;
}
bool getCOMMDirectiveAlignmentIsInBytes() const {
return COMMDirectiveAlignmentIsInBytes;
}
LCOMM::LCOMMType getLCOMMDirectiveAlignmentType() const {
return LCOMMDirectiveAlignmentType;
}
bool hasDotTypeDotSizeDirective() const {return HasDotTypeDotSizeDirective;}
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 doesDwarfUseRelocationsAcrossSections() const {
return DwarfUsesRelocationsAcrossSections;
}
bool useDwarfRegNumForCFI() const {
return DwarfRegNumForCFI;
}
void addInitialFrameState(const MCCFIInstruction &Inst) {
InitialFrameState.push_back(Inst);
}
const std::vector<MCCFIInstruction> &getInitialFrameState() const {
return InitialFrameState;
}
};
}
#endif