llvm-6502/include/llvm/MC/MCAsmInfo.h
2009-09-15 23:11:32 +00:00

486 lines
19 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_TARGET_ASM_INFO_H
#define LLVM_TARGET_ASM_INFO_H
#include <cassert>
namespace llvm {
/// MCAsmInfo - This class is intended to be used as a base class for asm
/// properties and features specific to the target.
namespace ExceptionHandling { enum ExceptionsType { None, Dwarf, SjLj }; }
class MCAsmInfo {
protected:
//===------------------------------------------------------------------===//
// Properties to be set by the target writer, used to configure asm printer.
//
/// ZeroFillDirective - Directive for emitting a global to the ZeroFill
/// section on this target. Null if this target doesn't support zerofill.
const char *ZeroFillDirective; // Default is null.
/// NonexecutableStackDirective - Directive for declaring to the
/// linker and beyond that the emitted code does not require stack
/// memory to be executable.
const char *NonexecutableStackDirective; // Default is null.
/// NeedsSet - True if target asm treats expressions in data directives
/// as linktime-relocatable. For assembly-time computation, we need to
/// use a .set. Thus:
/// .set w, x-y
/// .long w
/// is computed at assembly time, while
/// .long x-y
/// is relocated if the relative locations of x and y change at linktime.
/// We want both these things in different places.
bool NeedsSet; // Defaults 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 "$".
/// SeparatorChar - This character, if specified, is used to separate
/// instructions from each other when on the same line. This is used to
/// measure inline asm instructions.
char SeparatorChar; // Defaults to ';'
/// CommentColumn - This indicates the comment num (zero-based) at
/// which asm comments should be printed.
unsigned CommentColumn; // Defaults to 60
/// CommentString - This indicates the comment character used by the
/// assembler.
const char *CommentString; // 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 ""
/// PersonalityPrefix/Suffix - If these are nonempty, these strings will
/// enclose any personality function in the common frame section.
///
const char *PersonalityPrefix; // Defaults to ""
const char *PersonalitySuffix; // Defaults to ""
/// NeedsIndirectEncoding - If set, we need to set the indirect encoding bit
/// for EH in Dwarf.
///
bool NeedsIndirectEncoding; // Defaults to false
/// 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"
/// 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;
//===--- 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"
const char *ZeroDirectiveSuffix; // Defaults to ""
/// 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"
/// 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.
//===--- 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
//===--- Section Switching Directives ---------------------------------===//
/// JumpTableDirective - if non-null, the directive to emit before jump
/// table entries. FIXME: REMOVE THIS.
const char *JumpTableDirective; // Defaults to NULL.
const char *PICJumpTableDirective; // Defaults to NULL.
//===--- 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.
/// SetDirective - This is the name of a directive that can be used to tell
/// the assembler to set the value of a variable to some expression.
const char *SetDirective; // Defaults to null.
/// LCOMMDirective - This is the name of a directive (if supported) that can
/// be used to efficiently declare a local (internal) block of zero
/// initialized data in the .bss/.data section. The syntax expected is:
/// @verbatim <LCOMMDirective> SYMBOLNAME LENGTHINBYTES, ALIGNMENT
/// @endverbatim
const char *LCOMMDirective; // Defaults to null.
const char *COMMDirective; // Defaults to "\t.comm\t".
/// COMMDirectiveTakesAlignment - True if COMMDirective take a third
/// argument that specifies the alignment of the declaration.
bool COMMDirectiveTakesAlignment; // 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.
/// UsedDirective - This directive, if non-null, is used to declare a global
/// as being used somehow that the assembler can't see. This prevents dead
/// code elimination on some targets.
const char *UsedDirective; // Defaults to NULL.
/// 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.
/// HiddenDirective - This directive, if non-null, is used to declare a
/// global or function as having hidden visibility.
const char *HiddenDirective; // Defaults to "\t.hidden\t".
/// ProtectedDirective - This directive, if non-null, is used to declare a
/// global or function as having protected visibility.
const char *ProtectedDirective; // Defaults to "\t.protected\t".
//===--- Dwarf Emission Directives -----------------------------------===//
/// AbsoluteDebugSectionOffsets - True if we should emit abolute section
/// offsets for debug information.
bool AbsoluteDebugSectionOffsets; // Defaults to false.
/// AbsoluteEHSectionOffsets - True if we should emit abolute section
/// offsets for EH information. Defaults to false.
bool AbsoluteEHSectionOffsets;
/// HasLEB128 - True if target asm supports leb128 directives.
bool HasLEB128; // Defaults to false.
/// hasDotLocAndDotFile - True if target asm supports .loc and .file
/// directives for emitting debugging information.
bool HasDotLocAndDotFile; // 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
/// RequiresFrameSection - true if the Dwarf2 output needs a frame section
bool DwarfRequiresFrameSection; // Defaults to true.
/// DwarfUsesInlineInfoSection - True if DwarfDebugInlineSection is used to
/// encode inline subroutine information.
bool DwarfUsesInlineInfoSection; // Defaults to false.
/// Is_EHSymbolPrivate - If set, the "_foo.eh" is made private so that it
/// doesn't show up in the symbol table of the object file.
bool Is_EHSymbolPrivate; // Defaults to true.
/// GlobalEHDirective - This is the directive used to make exception frame
/// tables globally visible.
const char *GlobalEHDirective; // Defaults to NULL.
/// SupportsWeakEmptyEHFrame - True if target assembler and linker will
/// handle a weak_definition of constant 0 for an omitted EH frame.
bool SupportsWeakOmittedEHFrame; // Defaults to true.
/// DwarfSectionOffsetDirective - Special section offset directive.
const char* DwarfSectionOffsetDirective; // Defaults to NULL
//===--- CBE Asm Translation Table -----------------------------------===//
const char *const *AsmTransCBE; // Defaults to empty
public:
explicit MCAsmInfo();
virtual ~MCAsmInfo();
/// getSLEB128Size - Compute the number of bytes required for a signed
/// leb128 value.
static unsigned getSLEB128Size(int Value);
/// getULEB128Size - Compute the number of bytes required for an unsigned
/// leb128 value.
static unsigned getULEB128Size(unsigned Value);
// 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);
}
bool usesSunStyleELFSectionSwitchSyntax() const {
return SunStyleELFSectionSwitchSyntax;
}
bool usesELFSectionDirectiveForBSS() const {
return UsesELFSectionDirectiveForBSS;
}
// Accessors.
//
const char *getZeroFillDirective() const {
return ZeroFillDirective;
}
const char *getNonexecutableStackDirective() const {
return NonexecutableStackDirective;
}
bool needsSet() const {
return NeedsSet;
}
unsigned getMaxInstLength() const {
return MaxInstLength;
}
const char *getPCSymbol() const {
return PCSymbol;
}
char getSeparatorChar() const {
return SeparatorChar;
}
unsigned getCommentColumn() const {
return CommentColumn;
}
const char *getCommentString() const {
return CommentString;
}
const char *getGlobalPrefix() const {
return GlobalPrefix;
}
const char *getPrivateGlobalPrefix() const {
return PrivateGlobalPrefix;
}
const char *getLinkerPrivateGlobalPrefix() const {
return LinkerPrivateGlobalPrefix;
}
const char *getPersonalityPrefix() const {
return PersonalityPrefix;
}
const char *getPersonalitySuffix() const {
return PersonalitySuffix;
}
bool getNeedsIndirectEncoding() const {
return NeedsIndirectEncoding;
}
const char *getInlineAsmStart() const {
return InlineAsmStart;
}
const char *getInlineAsmEnd() const {
return InlineAsmEnd;
}
unsigned getAssemblerDialect() const {
return AssemblerDialect;
}
bool doesAllowQuotesInName() const {
return AllowQuotesInName;
}
const char *getZeroDirective() const {
return ZeroDirective;
}
const char *getZeroDirectiveSuffix() const {
return ZeroDirectiveSuffix;
}
const char *getAsciiDirective() const {
return AsciiDirective;
}
const char *getAscizDirective() const {
return AscizDirective;
}
const char *getJumpTableDirective(bool isPIC) const {
return isPIC ? PICJumpTableDirective : JumpTableDirective;
}
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;
}
const char *getSetDirective() const {
return SetDirective;
}
const char *getLCOMMDirective() const {
return LCOMMDirective;
}
const char *getCOMMDirective() const {
return COMMDirective;
}
bool getCOMMDirectiveTakesAlignment() const {
return COMMDirectiveTakesAlignment;
}
bool hasDotTypeDotSizeDirective() const {
return HasDotTypeDotSizeDirective;
}
bool hasSingleParameterDotFile() const {
return HasSingleParameterDotFile;
}
const char *getUsedDirective() const {
return UsedDirective;
}
const char *getWeakRefDirective() const {
return WeakRefDirective;
}
const char *getWeakDefDirective() const {
return WeakDefDirective;
}
const char *getHiddenDirective() const {
return HiddenDirective;
}
const char *getProtectedDirective() const {
return ProtectedDirective;
}
bool isAbsoluteDebugSectionOffsets() const {
return AbsoluteDebugSectionOffsets;
}
bool isAbsoluteEHSectionOffsets() const {
return AbsoluteEHSectionOffsets;
}
bool hasLEB128() const {
return HasLEB128;
}
bool hasDotLocAndDotFile() const {
return HasDotLocAndDotFile;
}
bool doesSupportDebugInformation() const {
return SupportsDebugInformation;
}
bool doesSupportExceptionHandling() const {
return ExceptionsType != ExceptionHandling::None;
}
ExceptionHandling::ExceptionsType getExceptionHandlingType() const {
return ExceptionsType;
}
bool doesDwarfRequireFrameSection() const {
return DwarfRequiresFrameSection;
}
bool doesDwarfUsesInlineInfoSection() const {
return DwarfUsesInlineInfoSection;
}
bool is_EHSymbolPrivate() const {
return Is_EHSymbolPrivate;
}
const char *getGlobalEHDirective() const {
return GlobalEHDirective;
}
bool getSupportsWeakOmittedEHFrame() const {
return SupportsWeakOmittedEHFrame;
}
const char *getDwarfSectionOffsetDirective() const {
return DwarfSectionOffsetDirective;
}
const char *const *getAsmCBE() const {
return AsmTransCBE;
}
};
}
#endif