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      1 //===-- llvm/MC/MCAsmInfo.h - Asm info --------------------------*- C++ -*-===//
      2 //
      3 //                     The LLVM Compiler Infrastructure
      4 //
      5 // This file is distributed under the University of Illinois Open Source
      6 // License. See LICENSE.TXT for details.
      7 //
      8 //===----------------------------------------------------------------------===//
      9 //
     10 // This file contains a class to be used as the basis for target specific
     11 // asm writers.  This class primarily takes care of global printing constants,
     12 // which are used in very similar ways across all targets.
     13 //
     14 //===----------------------------------------------------------------------===//
     15 
     16 #ifndef LLVM_TARGET_ASM_INFO_H
     17 #define LLVM_TARGET_ASM_INFO_H
     18 
     19 #include "llvm/MC/MachineLocation.h"
     20 #include "llvm/MC/MCDirectives.h"
     21 #include <cassert>
     22 #include <vector>
     23 
     24 namespace llvm {
     25   class MCExpr;
     26   class MCSection;
     27   class MCStreamer;
     28   class MCSymbol;
     29   class MCContext;
     30 
     31   namespace ExceptionHandling {
     32     enum ExceptionsType { None, DwarfCFI, SjLj, ARM, Win64 };
     33   }
     34 
     35   namespace LCOMM {
     36     enum LCOMMType { NoAlignment, ByteAlignment, Log2Alignment };
     37   }
     38 
     39   /// MCAsmInfo - This class is intended to be used as a base class for asm
     40   /// properties and features specific to the target.
     41   class MCAsmInfo {
     42   protected:
     43     //===------------------------------------------------------------------===//
     44     // Properties to be set by the target writer, used to configure asm printer.
     45     //
     46 
     47     /// PointerSize - Pointer size in bytes.
     48     ///               Default is 4.
     49     unsigned PointerSize;
     50 
     51     /// IsLittleEndian - True if target is little endian.
     52     ///                  Default is true.
     53     bool IsLittleEndian;
     54 
     55     /// StackGrowsUp - True if target stack grow up.
     56     ///                Default is false.
     57     bool StackGrowsUp;
     58 
     59     /// HasSubsectionsViaSymbols - True if this target has the MachO
     60     /// .subsections_via_symbols directive.
     61     bool HasSubsectionsViaSymbols;           // Default is false.
     62 
     63     /// HasMachoZeroFillDirective - True if this is a MachO target that supports
     64     /// the macho-specific .zerofill directive for emitting BSS Symbols.
     65     bool HasMachoZeroFillDirective;               // Default is false.
     66 
     67     /// HasMachoTBSSDirective - True if this is a MachO target that supports
     68     /// the macho-specific .tbss directive for emitting thread local BSS Symbols
     69     bool HasMachoTBSSDirective;                 // Default is false.
     70 
     71     /// HasStaticCtorDtorReferenceInStaticMode - True if the compiler should
     72     /// emit a ".reference .constructors_used" or ".reference .destructors_used"
     73     /// directive after the a static ctor/dtor list.  This directive is only
     74     /// emitted in Static relocation model.
     75     bool HasStaticCtorDtorReferenceInStaticMode;  // Default is false.
     76 
     77     /// LinkerRequiresNonEmptyDwarfLines - True if the linker has a bug and
     78     /// requires that the debug_line section be of a minimum size. In practice
     79     /// such a linker requires a non empty line sequence if a file is present.
     80     bool LinkerRequiresNonEmptyDwarfLines; // Default to false.
     81 
     82     /// MaxInstLength - This is the maximum possible length of an instruction,
     83     /// which is needed to compute the size of an inline asm.
     84     unsigned MaxInstLength;                  // Defaults to 4.
     85 
     86     /// PCSymbol - The symbol used to represent the current PC.  Used in PC
     87     /// relative expressions.
     88     const char *PCSymbol;                    // Defaults to "$".
     89 
     90     /// SeparatorString - This string, if specified, is used to separate
     91     /// instructions from each other when on the same line.
     92     const char *SeparatorString;             // Defaults to ';'
     93 
     94     /// CommentColumn - This indicates the comment num (zero-based) at
     95     /// which asm comments should be printed.
     96     unsigned CommentColumn;                  // Defaults to 40
     97 
     98     /// CommentString - This indicates the comment character used by the
     99     /// assembler.
    100     const char *CommentString;               // Defaults to "#"
    101 
    102     /// LabelSuffix - This is appended to emitted labels.
    103     const char *LabelSuffix;                 // Defaults to ":"
    104 
    105     /// GlobalPrefix - If this is set to a non-empty string, it is prepended
    106     /// onto all global symbols.  This is often used for "_" or ".".
    107     const char *GlobalPrefix;                // Defaults to ""
    108 
    109     /// PrivateGlobalPrefix - This prefix is used for globals like constant
    110     /// pool entries that are completely private to the .s file and should not
    111     /// have names in the .o file.  This is often "." or "L".
    112     const char *PrivateGlobalPrefix;         // Defaults to "."
    113 
    114     /// LinkerPrivateGlobalPrefix - This prefix is used for symbols that should
    115     /// be passed through the assembler but be removed by the linker.  This
    116     /// is "l" on Darwin, currently used for some ObjC metadata.
    117     const char *LinkerPrivateGlobalPrefix;   // Defaults to ""
    118 
    119     /// InlineAsmStart/End - If these are nonempty, they contain a directive to
    120     /// emit before and after an inline assembly statement.
    121     const char *InlineAsmStart;              // Defaults to "#APP\n"
    122     const char *InlineAsmEnd;                // Defaults to "#NO_APP\n"
    123 
    124     /// Code16Directive, Code32Directive, Code64Directive - These are assembly
    125     /// directives that tells the assembler to interpret the following
    126     /// instructions differently.
    127     const char *Code16Directive;             // Defaults to ".code16"
    128     const char *Code32Directive;             // Defaults to ".code32"
    129     const char *Code64Directive;             // Defaults to ".code64"
    130 
    131     /// AssemblerDialect - Which dialect of an assembler variant to use.
    132     unsigned AssemblerDialect;               // Defaults to 0
    133 
    134     /// AllowQuotesInName - This is true if the assembler allows for complex
    135     /// symbol names to be surrounded in quotes.  This defaults to false.
    136     bool AllowQuotesInName;
    137 
    138     /// AllowNameToStartWithDigit - This is true if the assembler allows symbol
    139     /// names to start with a digit (e.g., "0x0021").  This defaults to false.
    140     bool AllowNameToStartWithDigit;
    141 
    142     /// AllowPeriodsInName - This is true if the assembler allows periods in
    143     /// symbol names.  This defaults to true.
    144     bool AllowPeriodsInName;
    145 
    146     /// AllowUTF8 - This is true if the assembler accepts UTF-8 input.
    147     // FIXME: Make this a more general encoding setting?
    148     bool AllowUTF8;
    149 
    150     /// UseDataRegionDirectives - This is true if data region markers should
    151     /// be printed as ".data_region/.end_data_region" directives. If false,
    152     /// use "$d/$a" labels instead.
    153     bool UseDataRegionDirectives;
    154 
    155     //===--- Data Emission Directives -------------------------------------===//
    156 
    157     /// ZeroDirective - this should be set to the directive used to get some
    158     /// number of zero bytes emitted to the current section.  Common cases are
    159     /// "\t.zero\t" and "\t.space\t".  If this is set to null, the
    160     /// Data*bitsDirective's will be used to emit zero bytes.
    161     const char *ZeroDirective;               // Defaults to "\t.zero\t"
    162 
    163     /// AsciiDirective - This directive allows emission of an ascii string with
    164     /// the standard C escape characters embedded into it.
    165     const char *AsciiDirective;              // Defaults to "\t.ascii\t"
    166 
    167     /// AscizDirective - If not null, this allows for special handling of
    168     /// zero terminated strings on this target.  This is commonly supported as
    169     /// ".asciz".  If a target doesn't support this, it can be set to null.
    170     const char *AscizDirective;              // Defaults to "\t.asciz\t"
    171 
    172     /// DataDirectives - These directives are used to output some unit of
    173     /// integer data to the current section.  If a data directive is set to
    174     /// null, smaller data directives will be used to emit the large sizes.
    175     const char *Data8bitsDirective;          // Defaults to "\t.byte\t"
    176     const char *Data16bitsDirective;         // Defaults to "\t.short\t"
    177     const char *Data32bitsDirective;         // Defaults to "\t.long\t"
    178     const char *Data64bitsDirective;         // Defaults to "\t.quad\t"
    179 
    180     /// GPRel64Directive - if non-null, a directive that is used to emit a word
    181     /// which should be relocated as a 64-bit GP-relative offset, e.g. .gpdword
    182     /// on Mips.
    183     const char *GPRel64Directive;            // Defaults to NULL.
    184 
    185     /// GPRel32Directive - if non-null, a directive that is used to emit a word
    186     /// which should be relocated as a 32-bit GP-relative offset, e.g. .gpword
    187     /// on Mips or .gprel32 on Alpha.
    188     const char *GPRel32Directive;            // Defaults to NULL.
    189 
    190     /// getDataASDirective - Return the directive that should be used to emit
    191     /// data of the specified size to the specified numeric address space.
    192     virtual const char *getDataASDirective(unsigned Size, unsigned AS) const {
    193       assert(AS != 0 && "Don't know the directives for default addr space");
    194       return 0;
    195     }
    196 
    197     /// SunStyleELFSectionSwitchSyntax - This is true if this target uses "Sun
    198     /// Style" syntax for section switching ("#alloc,#write" etc) instead of the
    199     /// normal ELF syntax (,"a,w") in .section directives.
    200     bool SunStyleELFSectionSwitchSyntax;     // Defaults to false.
    201 
    202     /// UsesELFSectionDirectiveForBSS - This is true if this target uses ELF
    203     /// '.section' directive before the '.bss' one. It's used for PPC/Linux
    204     /// which doesn't support the '.bss' directive only.
    205     bool UsesELFSectionDirectiveForBSS;      // Defaults to false.
    206 
    207     /// HasMicrosoftFastStdCallMangling - True if this target uses microsoft
    208     /// style mangling for functions with X86_StdCall/X86_FastCall calling
    209     /// convention.
    210     bool HasMicrosoftFastStdCallMangling;    // Defaults to false.
    211 
    212     //===--- Alignment Information ----------------------------------------===//
    213 
    214     /// AlignDirective - The directive used to emit round up to an alignment
    215     /// boundary.
    216     ///
    217     const char *AlignDirective;              // Defaults to "\t.align\t"
    218 
    219     /// AlignmentIsInBytes - If this is true (the default) then the asmprinter
    220     /// emits ".align N" directives, where N is the number of bytes to align to.
    221     /// Otherwise, it emits ".align log2(N)", e.g. 3 to align to an 8 byte
    222     /// boundary.
    223     bool AlignmentIsInBytes;                 // Defaults to true
    224 
    225     /// TextAlignFillValue - If non-zero, this is used to fill the executable
    226     /// space created as the result of a alignment directive.
    227     unsigned TextAlignFillValue;             // Defaults to 0
    228 
    229     //===--- Global Variable Emission Directives --------------------------===//
    230 
    231     /// GlobalDirective - This is the directive used to declare a global entity.
    232     ///
    233     const char *GlobalDirective;             // Defaults to NULL.
    234 
    235     /// ExternDirective - This is the directive used to declare external
    236     /// globals.
    237     ///
    238     const char *ExternDirective;             // Defaults to NULL.
    239 
    240     /// HasSetDirective - True if the assembler supports the .set directive.
    241     bool HasSetDirective;                    // Defaults to true.
    242 
    243     /// HasAggressiveSymbolFolding - False if the assembler requires that we use
    244     /// Lc = a - b
    245     /// .long Lc
    246     /// instead of
    247     /// .long a - b
    248     bool HasAggressiveSymbolFolding;           // Defaults to true.
    249 
    250     /// COMMDirectiveAlignmentIsInBytes - True is .comm's and .lcomms optional
    251     /// alignment is to be specified in bytes instead of log2(n).
    252     bool COMMDirectiveAlignmentIsInBytes;    // Defaults to true;
    253 
    254     /// LCOMMDirectiveAlignment - Describes if the .lcomm directive for the
    255     /// target supports an alignment argument and how it is interpreted.
    256     LCOMM::LCOMMType LCOMMDirectiveAlignmentType; // Defaults to NoAlignment.
    257 
    258     /// HasDotTypeDotSizeDirective - True if the target has .type and .size
    259     /// directives, this is true for most ELF targets.
    260     bool HasDotTypeDotSizeDirective;         // Defaults to true.
    261 
    262     /// HasSingleParameterDotFile - True if the target has a single parameter
    263     /// .file directive, this is true for ELF targets.
    264     bool HasSingleParameterDotFile;          // Defaults to true.
    265 
    266     /// HasNoDeadStrip - True if this target supports the MachO .no_dead_strip
    267     /// directive.
    268     bool HasNoDeadStrip;                     // Defaults to false.
    269 
    270     /// HasSymbolResolver - True if this target supports the MachO
    271     /// .symbol_resolver directive.
    272     bool HasSymbolResolver;                     // Defaults to false.
    273 
    274     /// WeakRefDirective - This directive, if non-null, is used to declare a
    275     /// global as being a weak undefined symbol.
    276     const char *WeakRefDirective;            // Defaults to NULL.
    277 
    278     /// WeakDefDirective - This directive, if non-null, is used to declare a
    279     /// global as being a weak defined symbol.
    280     const char *WeakDefDirective;            // Defaults to NULL.
    281 
    282     /// LinkOnceDirective - This directive, if non-null is used to declare a
    283     /// global as being a weak defined symbol.  This is used on cygwin/mingw.
    284     const char *LinkOnceDirective;           // Defaults to NULL.
    285 
    286     /// HiddenVisibilityAttr - This attribute, if not MCSA_Invalid, is used to
    287     /// declare a symbol as having hidden visibility.
    288     MCSymbolAttr HiddenVisibilityAttr;       // Defaults to MCSA_Hidden.
    289 
    290     /// HiddenDeclarationVisibilityAttr - This attribute, if not MCSA_Invalid,
    291     /// is used to declare an undefined symbol as having hidden visibility.
    292     MCSymbolAttr HiddenDeclarationVisibilityAttr;   // Defaults to MCSA_Hidden.
    293 
    294 
    295     /// ProtectedVisibilityAttr - This attribute, if not MCSA_Invalid, is used
    296     /// to declare a symbol as having protected visibility.
    297     MCSymbolAttr ProtectedVisibilityAttr;    // Defaults to MCSA_Protected
    298 
    299     //===--- Dwarf Emission Directives -----------------------------------===//
    300 
    301     /// HasLEB128 - True if target asm supports leb128 directives.
    302     bool HasLEB128;                          // Defaults to false.
    303 
    304     /// SupportsDebugInformation - True if target supports emission of debugging
    305     /// information.
    306     bool SupportsDebugInformation;           // Defaults to false.
    307 
    308     /// SupportsExceptionHandling - True if target supports exception handling.
    309     ExceptionHandling::ExceptionsType ExceptionsType; // Defaults to None
    310 
    311     /// DwarfUsesInlineInfoSection - True if DwarfDebugInlineSection is used to
    312     /// encode inline subroutine information.
    313     bool DwarfUsesInlineInfoSection;         // Defaults to false.
    314 
    315     /// DwarfSectionOffsetDirective - Special section offset directive.
    316     const char* DwarfSectionOffsetDirective; // Defaults to NULL
    317 
    318     /// DwarfUsesRelocationsAcrossSections - True if Dwarf2 output generally
    319     /// uses relocations for references to other .debug_* sections.
    320     bool DwarfUsesRelocationsAcrossSections;
    321 
    322     /// DwarfRegNumForCFI - True if dwarf register numbers are printed
    323     /// instead of symbolic register names in .cfi_* directives.
    324     bool DwarfRegNumForCFI;  // Defaults to false;
    325 
    326     //===--- Prologue State ----------------------------------------------===//
    327 
    328     std::vector<MachineMove> InitialFrameState;
    329 
    330   public:
    331     explicit MCAsmInfo();
    332     virtual ~MCAsmInfo();
    333 
    334     // FIXME: move these methods to DwarfPrinter when the JIT stops using them.
    335     static unsigned getSLEB128Size(int Value);
    336     static unsigned getULEB128Size(unsigned Value);
    337 
    338     /// getPointerSize - Get the pointer size in bytes.
    339     unsigned getPointerSize() const {
    340       return PointerSize;
    341     }
    342 
    343     /// islittleendian - True if the target is little endian.
    344     bool isLittleEndian() const {
    345       return IsLittleEndian;
    346     }
    347 
    348     /// isStackGrowthDirectionUp - True if target stack grow up.
    349     bool isStackGrowthDirectionUp() const {
    350       return StackGrowsUp;
    351     }
    352 
    353     bool hasSubsectionsViaSymbols() const { return HasSubsectionsViaSymbols; }
    354 
    355     // Data directive accessors.
    356     //
    357     const char *getData8bitsDirective(unsigned AS = 0) const {
    358       return AS == 0 ? Data8bitsDirective : getDataASDirective(8, AS);
    359     }
    360     const char *getData16bitsDirective(unsigned AS = 0) const {
    361       return AS == 0 ? Data16bitsDirective : getDataASDirective(16, AS);
    362     }
    363     const char *getData32bitsDirective(unsigned AS = 0) const {
    364       return AS == 0 ? Data32bitsDirective : getDataASDirective(32, AS);
    365     }
    366     const char *getData64bitsDirective(unsigned AS = 0) const {
    367       return AS == 0 ? Data64bitsDirective : getDataASDirective(64, AS);
    368     }
    369     const char *getGPRel64Directive() const { return GPRel64Directive; }
    370     const char *getGPRel32Directive() const { return GPRel32Directive; }
    371 
    372     /// getNonexecutableStackSection - Targets can implement this method to
    373     /// specify a section to switch to if the translation unit doesn't have any
    374     /// trampolines that require an executable stack.
    375     virtual const MCSection *getNonexecutableStackSection(MCContext &Ctx) const{
    376       return 0;
    377     }
    378 
    379     virtual const MCExpr *
    380     getExprForPersonalitySymbol(const MCSymbol *Sym,
    381                                 unsigned Encoding,
    382                                 MCStreamer &Streamer) const;
    383 
    384     const MCExpr *
    385     getExprForFDESymbol(const MCSymbol *Sym,
    386                         unsigned Encoding,
    387                         MCStreamer &Streamer) const;
    388 
    389     bool usesSunStyleELFSectionSwitchSyntax() const {
    390       return SunStyleELFSectionSwitchSyntax;
    391     }
    392 
    393     bool usesELFSectionDirectiveForBSS() const {
    394       return UsesELFSectionDirectiveForBSS;
    395     }
    396 
    397     bool hasMicrosoftFastStdCallMangling() const {
    398       return HasMicrosoftFastStdCallMangling;
    399     }
    400 
    401     // Accessors.
    402     //
    403     bool hasMachoZeroFillDirective() const { return HasMachoZeroFillDirective; }
    404     bool hasMachoTBSSDirective() const { return HasMachoTBSSDirective; }
    405     bool hasStaticCtorDtorReferenceInStaticMode() const {
    406       return HasStaticCtorDtorReferenceInStaticMode;
    407     }
    408     bool getLinkerRequiresNonEmptyDwarfLines() const {
    409       return LinkerRequiresNonEmptyDwarfLines;
    410     }
    411     unsigned getMaxInstLength() const {
    412       return MaxInstLength;
    413     }
    414     const char *getPCSymbol() const {
    415       return PCSymbol;
    416     }
    417     const char *getSeparatorString() const {
    418       return SeparatorString;
    419     }
    420     unsigned getCommentColumn() const {
    421       return CommentColumn;
    422     }
    423     const char *getCommentString() const {
    424       return CommentString;
    425     }
    426     const char *getLabelSuffix() const {
    427       return LabelSuffix;
    428     }
    429     const char *getGlobalPrefix() const {
    430       return GlobalPrefix;
    431     }
    432     const char *getPrivateGlobalPrefix() const {
    433       return PrivateGlobalPrefix;
    434     }
    435     const char *getLinkerPrivateGlobalPrefix() const {
    436       return LinkerPrivateGlobalPrefix;
    437     }
    438     const char *getInlineAsmStart() const {
    439       return InlineAsmStart;
    440     }
    441     const char *getInlineAsmEnd() const {
    442       return InlineAsmEnd;
    443     }
    444     const char *getCode16Directive() const {
    445       return Code16Directive;
    446     }
    447     const char *getCode32Directive() const {
    448       return Code32Directive;
    449     }
    450     const char *getCode64Directive() const {
    451       return Code64Directive;
    452     }
    453     unsigned getAssemblerDialect() const {
    454       return AssemblerDialect;
    455     }
    456     bool doesAllowQuotesInName() const {
    457       return AllowQuotesInName;
    458     }
    459     bool doesAllowNameToStartWithDigit() const {
    460       return AllowNameToStartWithDigit;
    461     }
    462     bool doesAllowPeriodsInName() const {
    463       return AllowPeriodsInName;
    464     }
    465     bool doesAllowUTF8() const {
    466       return AllowUTF8;
    467     }
    468     bool doesSupportDataRegionDirectives() const {
    469       return UseDataRegionDirectives;
    470     }
    471     const char *getZeroDirective() const {
    472       return ZeroDirective;
    473     }
    474     const char *getAsciiDirective() const {
    475       return AsciiDirective;
    476     }
    477     const char *getAscizDirective() const {
    478       return AscizDirective;
    479     }
    480     const char *getAlignDirective() const {
    481       return AlignDirective;
    482     }
    483     bool getAlignmentIsInBytes() const {
    484       return AlignmentIsInBytes;
    485     }
    486     unsigned getTextAlignFillValue() const {
    487       return TextAlignFillValue;
    488     }
    489     const char *getGlobalDirective() const {
    490       return GlobalDirective;
    491     }
    492     const char *getExternDirective() const {
    493       return ExternDirective;
    494     }
    495     bool hasSetDirective() const { return HasSetDirective; }
    496     bool hasAggressiveSymbolFolding() const {
    497       return HasAggressiveSymbolFolding;
    498     }
    499     bool getCOMMDirectiveAlignmentIsInBytes() const {
    500       return COMMDirectiveAlignmentIsInBytes;
    501     }
    502     LCOMM::LCOMMType getLCOMMDirectiveAlignmentType() const {
    503       return LCOMMDirectiveAlignmentType;
    504     }
    505     bool hasDotTypeDotSizeDirective() const {return HasDotTypeDotSizeDirective;}
    506     bool hasSingleParameterDotFile() const { return HasSingleParameterDotFile; }
    507     bool hasNoDeadStrip() const { return HasNoDeadStrip; }
    508     bool hasSymbolResolver() const { return HasSymbolResolver; }
    509     const char *getWeakRefDirective() const { return WeakRefDirective; }
    510     const char *getWeakDefDirective() const { return WeakDefDirective; }
    511     const char *getLinkOnceDirective() const { return LinkOnceDirective; }
    512 
    513     MCSymbolAttr getHiddenVisibilityAttr() const { return HiddenVisibilityAttr;}
    514     MCSymbolAttr getHiddenDeclarationVisibilityAttr() const {
    515       return HiddenDeclarationVisibilityAttr;
    516     }
    517     MCSymbolAttr getProtectedVisibilityAttr() const {
    518       return ProtectedVisibilityAttr;
    519     }
    520     bool hasLEB128() const {
    521       return HasLEB128;
    522     }
    523     bool doesSupportDebugInformation() const {
    524       return SupportsDebugInformation;
    525     }
    526     bool doesSupportExceptionHandling() const {
    527       return ExceptionsType != ExceptionHandling::None;
    528     }
    529     ExceptionHandling::ExceptionsType getExceptionHandlingType() const {
    530       return ExceptionsType;
    531     }
    532     bool isExceptionHandlingDwarf() const {
    533       return
    534         (ExceptionsType == ExceptionHandling::DwarfCFI ||
    535          ExceptionsType == ExceptionHandling::ARM ||
    536          ExceptionsType == ExceptionHandling::Win64);
    537     }
    538     bool doesDwarfUseInlineInfoSection() const {
    539       return DwarfUsesInlineInfoSection;
    540     }
    541     const char *getDwarfSectionOffsetDirective() const {
    542       return DwarfSectionOffsetDirective;
    543     }
    544     bool doesDwarfUseRelocationsAcrossSections() const {
    545       return DwarfUsesRelocationsAcrossSections;
    546     }
    547     bool useDwarfRegNumForCFI() const {
    548       return DwarfRegNumForCFI;
    549     }
    550 
    551     void addInitialFrameState(MCSymbol *label, const MachineLocation &D,
    552                               const MachineLocation &S) {
    553       InitialFrameState.push_back(MachineMove(label, D, S));
    554     }
    555     const std::vector<MachineMove> &getInitialFrameState() const {
    556       return InitialFrameState;
    557     }
    558   };
    559 }
    560 
    561 #endif
    562