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Diffstat (limited to 'include/llvm/MC/MCAssembler.h')
| -rw-r--r-- | include/llvm/MC/MCAssembler.h | 661 |
1 files changed, 661 insertions, 0 deletions
diff --git a/include/llvm/MC/MCAssembler.h b/include/llvm/MC/MCAssembler.h new file mode 100644 index 0000000..892f548 --- /dev/null +++ b/include/llvm/MC/MCAssembler.h @@ -0,0 +1,661 @@ +//===- MCAssembler.h - Object File Generation -------------------*- C++ -*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#ifndef LLVM_MC_MCASSEMBLER_H +#define LLVM_MC_MCASSEMBLER_H + +#include "llvm/ADT/SmallString.h" +#include "llvm/ADT/ilist.h" +#include "llvm/ADT/ilist_node.h" +#include "llvm/MC/MCValue.h" +#include "llvm/Support/Casting.h" +#include "llvm/Support/DataTypes.h" +#include <vector> // FIXME: Shouldn't be needed. + +namespace llvm { +class raw_ostream; +class MCAssembler; +class MCContext; +class MCSection; +class MCSectionData; + +class MCFragment : public ilist_node<MCFragment> { + MCFragment(const MCFragment&); // DO NOT IMPLEMENT + void operator=(const MCFragment&); // DO NOT IMPLEMENT + +public: + enum FragmentType { + FT_Data, + FT_Align, + FT_Fill, + FT_Org, + FT_ZeroFill + }; + +private: + FragmentType Kind; + + /// Parent - The data for the section this fragment is in. + MCSectionData *Parent; + + /// @name Assembler Backend Data + /// @{ + // + // FIXME: This could all be kept private to the assembler implementation. + + /// Offset - The offset of this fragment in its section. This is ~0 until + /// initialized. + uint64_t Offset; + + /// FileSize - The file size of this section. This is ~0 until initialized. + uint64_t FileSize; + + /// @} + +protected: + MCFragment(FragmentType _Kind, MCSectionData *_Parent = 0); + +public: + // Only for sentinel. + MCFragment(); + virtual ~MCFragment(); + + FragmentType getKind() const { return Kind; } + + MCSectionData *getParent() const { return Parent; } + void setParent(MCSectionData *Value) { Parent = Value; } + + // FIXME: This should be abstract, fix sentinel. + virtual uint64_t getMaxFileSize() const { + assert(0 && "Invalid getMaxFileSize call!"); + return 0; + }; + + /// @name Assembler Backend Support + /// @{ + // + // FIXME: This could all be kept private to the assembler implementation. + + uint64_t getAddress() const; + + uint64_t getFileSize() const { + assert(FileSize != ~UINT64_C(0) && "File size not set!"); + return FileSize; + } + void setFileSize(uint64_t Value) { + assert(Value <= getMaxFileSize() && "Invalid file size!"); + FileSize = Value; + } + + uint64_t getOffset() const { + assert(Offset != ~UINT64_C(0) && "File offset not set!"); + return Offset; + } + void setOffset(uint64_t Value) { Offset = Value; } + + /// @} + + static bool classof(const MCFragment *O) { return true; } +}; + +class MCDataFragment : public MCFragment { + SmallString<32> Contents; + +public: + MCDataFragment(MCSectionData *SD = 0) : MCFragment(FT_Data, SD) {} + + /// @name Accessors + /// @{ + + uint64_t getMaxFileSize() const { + return Contents.size(); + } + + SmallString<32> &getContents() { return Contents; } + const SmallString<32> &getContents() const { return Contents; } + + /// @} + + static bool classof(const MCFragment *F) { + return F->getKind() == MCFragment::FT_Data; + } + static bool classof(const MCDataFragment *) { return true; } +}; + +class MCAlignFragment : public MCFragment { + /// Alignment - The alignment to ensure, in bytes. + unsigned Alignment; + + /// Value - Value to use for filling padding bytes. + int64_t Value; + + /// ValueSize - The size of the integer (in bytes) of \arg Value. + unsigned ValueSize; + + /// MaxBytesToEmit - The maximum number of bytes to emit; if the alignment + /// cannot be satisfied in this width then this fragment is ignored. + unsigned MaxBytesToEmit; + +public: + MCAlignFragment(unsigned _Alignment, int64_t _Value, unsigned _ValueSize, + unsigned _MaxBytesToEmit, MCSectionData *SD = 0) + : MCFragment(FT_Align, SD), Alignment(_Alignment), + Value(_Value),ValueSize(_ValueSize), + MaxBytesToEmit(_MaxBytesToEmit) {} + + /// @name Accessors + /// @{ + + uint64_t getMaxFileSize() const { + return std::max(Alignment - 1, MaxBytesToEmit); + } + + unsigned getAlignment() const { return Alignment; } + + int64_t getValue() const { return Value; } + + unsigned getValueSize() const { return ValueSize; } + + unsigned getMaxBytesToEmit() const { return MaxBytesToEmit; } + + /// @} + + static bool classof(const MCFragment *F) { + return F->getKind() == MCFragment::FT_Align; + } + static bool classof(const MCAlignFragment *) { return true; } +}; + +class MCFillFragment : public MCFragment { + /// Value - Value to use for filling bytes. + MCValue Value; + + /// ValueSize - The size (in bytes) of \arg Value to use when filling. + unsigned ValueSize; + + /// Count - The number of copies of \arg Value to insert. + uint64_t Count; + +public: + MCFillFragment(MCValue _Value, unsigned _ValueSize, uint64_t _Count, + MCSectionData *SD = 0) + : MCFragment(FT_Fill, SD), + Value(_Value), ValueSize(_ValueSize), Count(_Count) {} + + /// @name Accessors + /// @{ + + uint64_t getMaxFileSize() const { + return ValueSize * Count; + } + + MCValue getValue() const { return Value; } + + unsigned getValueSize() const { return ValueSize; } + + uint64_t getCount() const { return Count; } + + /// @} + + static bool classof(const MCFragment *F) { + return F->getKind() == MCFragment::FT_Fill; + } + static bool classof(const MCFillFragment *) { return true; } +}; + +class MCOrgFragment : public MCFragment { + /// Offset - The offset this fragment should start at. + MCValue Offset; + + /// Value - Value to use for filling bytes. + int8_t Value; + +public: + MCOrgFragment(MCValue _Offset, int8_t _Value, MCSectionData *SD = 0) + : MCFragment(FT_Org, SD), + Offset(_Offset), Value(_Value) {} + + /// @name Accessors + /// @{ + + uint64_t getMaxFileSize() const { + // FIXME: This doesn't make much sense. + return ~UINT64_C(0); + } + + MCValue getOffset() const { return Offset; } + + uint8_t getValue() const { return Value; } + + /// @} + + static bool classof(const MCFragment *F) { + return F->getKind() == MCFragment::FT_Org; + } + static bool classof(const MCOrgFragment *) { return true; } +}; + +/// MCZeroFillFragment - Represent data which has a fixed size and alignment, +/// but requires no physical space in the object file. +class MCZeroFillFragment : public MCFragment { + /// Size - The size of this fragment. + uint64_t Size; + + /// Alignment - The alignment for this fragment. + unsigned Alignment; + +public: + MCZeroFillFragment(uint64_t _Size, unsigned _Alignment, MCSectionData *SD = 0) + : MCFragment(FT_ZeroFill, SD), + Size(_Size), Alignment(_Alignment) {} + + /// @name Accessors + /// @{ + + uint64_t getMaxFileSize() const { + // FIXME: This also doesn't make much sense, this method is misnamed. + return ~UINT64_C(0); + } + + uint64_t getSize() const { return Size; } + + unsigned getAlignment() const { return Alignment; } + + /// @} + + static bool classof(const MCFragment *F) { + return F->getKind() == MCFragment::FT_ZeroFill; + } + static bool classof(const MCZeroFillFragment *) { return true; } +}; + +// FIXME: Should this be a separate class, or just merged into MCSection? Since +// we anticipate the fast path being through an MCAssembler, the only reason to +// keep it out is for API abstraction. +class MCSectionData : public ilist_node<MCSectionData> { + MCSectionData(const MCSectionData&); // DO NOT IMPLEMENT + void operator=(const MCSectionData&); // DO NOT IMPLEMENT + +public: + /// Fixup - Represent a fixed size region of bytes inside some fragment which + /// needs to be rewritten. This region will either be rewritten by the + /// assembler or cause a relocation entry to be generated. + struct Fixup { + /// Fragment - The fragment containing the fixup. + MCFragment *Fragment; + + /// Offset - The offset inside the fragment which needs to be rewritten. + uint64_t Offset; + + /// Value - The expression to eventually write into the fragment. + // + // FIXME: We could probably get away with requiring the client to pass in an + // owned reference whose lifetime extends past that of the fixup. + MCValue Value; + + /// Size - The fixup size. + unsigned Size; + + /// FixedValue - The value to replace the fix up by. + // + // FIXME: This should not be here. + uint64_t FixedValue; + + public: + Fixup(MCFragment &_Fragment, uint64_t _Offset, const MCValue &_Value, + unsigned _Size) + : Fragment(&_Fragment), Offset(_Offset), Value(_Value), Size(_Size), + FixedValue(0) {} + }; + + typedef iplist<MCFragment> FragmentListType; + + typedef FragmentListType::const_iterator const_iterator; + typedef FragmentListType::iterator iterator; + + typedef std::vector<Fixup>::const_iterator const_fixup_iterator; + typedef std::vector<Fixup>::iterator fixup_iterator; + +private: + iplist<MCFragment> Fragments; + const MCSection *Section; + + /// Alignment - The maximum alignment seen in this section. + unsigned Alignment; + + /// @name Assembler Backend Data + /// @{ + // + // FIXME: This could all be kept private to the assembler implementation. + + /// Address - The computed address of this section. This is ~0 until + /// initialized. + uint64_t Address; + + /// Size - The content size of this section. This is ~0 until initialized. + uint64_t Size; + + /// FileSize - The size of this section in the object file. This is ~0 until + /// initialized. + uint64_t FileSize; + + /// LastFixupLookup - Cache for the last looked up fixup. + mutable unsigned LastFixupLookup; + + /// Fixups - The list of fixups in this section. + std::vector<Fixup> Fixups; + + /// @} + +public: + // Only for use as sentinel. + MCSectionData(); + MCSectionData(const MCSection &Section, MCAssembler *A = 0); + + const MCSection &getSection() const { return *Section; } + + unsigned getAlignment() const { return Alignment; } + void setAlignment(unsigned Value) { Alignment = Value; } + + /// @name Fragment Access + /// @{ + + const FragmentListType &getFragmentList() const { return Fragments; } + FragmentListType &getFragmentList() { return Fragments; } + + iterator begin() { return Fragments.begin(); } + const_iterator begin() const { return Fragments.begin(); } + + iterator end() { return Fragments.end(); } + const_iterator end() const { return Fragments.end(); } + + size_t size() const { return Fragments.size(); } + + bool empty() const { return Fragments.empty(); } + + /// @} + /// @name Fixup Access + /// @{ + + std::vector<Fixup> &getFixups() { + return Fixups; + } + + fixup_iterator fixup_begin() { + return Fixups.begin(); + } + + fixup_iterator fixup_end() { + return Fixups.end(); + } + + size_t fixup_size() const { return Fixups.size(); } + + /// @} + /// @name Assembler Backend Support + /// @{ + // + // FIXME: This could all be kept private to the assembler implementation. + + /// LookupFixup - Look up the fixup for the given \arg Fragment and \arg + /// Offset. + /// + /// If multiple fixups exist for the same fragment and offset it is undefined + /// which one is returned. + // + // FIXME: This isn't horribly slow in practice, but there are much nicer + // solutions to applying the fixups. + const Fixup *LookupFixup(const MCFragment *Fragment, uint64_t Offset) const; + + uint64_t getAddress() const { + assert(Address != ~UINT64_C(0) && "Address not set!"); + return Address; + } + void setAddress(uint64_t Value) { Address = Value; } + + uint64_t getSize() const { + assert(Size != ~UINT64_C(0) && "File size not set!"); + return Size; + } + void setSize(uint64_t Value) { Size = Value; } + + uint64_t getFileSize() const { + assert(FileSize != ~UINT64_C(0) && "File size not set!"); + return FileSize; + } + void setFileSize(uint64_t Value) { FileSize = Value; } + + /// @} +}; + +// FIXME: Same concerns as with SectionData. +class MCSymbolData : public ilist_node<MCSymbolData> { +public: + const MCSymbol *Symbol; + + /// Fragment - The fragment this symbol's value is relative to, if any. + MCFragment *Fragment; + + /// Offset - The offset to apply to the fragment address to form this symbol's + /// value. + uint64_t Offset; + + /// IsExternal - True if this symbol is visible outside this translation + /// unit. + unsigned IsExternal : 1; + + /// IsPrivateExtern - True if this symbol is private extern. + unsigned IsPrivateExtern : 1; + + /// CommonSize - The size of the symbol, if it is 'common', or 0. + // + // FIXME: Pack this in with other fields? We could put it in offset, since a + // common symbol can never get a definition. + uint64_t CommonSize; + + /// CommonAlign - The alignment of the symbol, if it is 'common'. + // + // FIXME: Pack this in with other fields? + unsigned CommonAlign; + + /// Flags - The Flags field is used by object file implementations to store + /// additional per symbol information which is not easily classified. + uint32_t Flags; + + /// Index - Index field, for use by the object file implementation. + uint64_t Index; + +public: + // Only for use as sentinel. + MCSymbolData(); + MCSymbolData(const MCSymbol &_Symbol, MCFragment *_Fragment, uint64_t _Offset, + MCAssembler *A = 0); + + /// @name Accessors + /// @{ + + const MCSymbol &getSymbol() const { return *Symbol; } + + MCFragment *getFragment() const { return Fragment; } + void setFragment(MCFragment *Value) { Fragment = Value; } + + uint64_t getOffset() const { return Offset; } + void setOffset(uint64_t Value) { Offset = Value; } + + /// @} + /// @name Symbol Attributes + /// @{ + + bool isExternal() const { return IsExternal; } + void setExternal(bool Value) { IsExternal = Value; } + + bool isPrivateExtern() const { return IsPrivateExtern; } + void setPrivateExtern(bool Value) { IsPrivateExtern = Value; } + + /// isCommon - Is this a 'common' symbol. + bool isCommon() const { return CommonSize != 0; } + + /// setCommon - Mark this symbol as being 'common'. + /// + /// \param Size - The size of the symbol. + /// \param Align - The alignment of the symbol. + void setCommon(uint64_t Size, unsigned Align) { + CommonSize = Size; + CommonAlign = Align; + } + + /// getCommonSize - Return the size of a 'common' symbol. + uint64_t getCommonSize() const { + assert(isCommon() && "Not a 'common' symbol!"); + return CommonSize; + } + + /// getCommonAlignment - Return the alignment of a 'common' symbol. + unsigned getCommonAlignment() const { + assert(isCommon() && "Not a 'common' symbol!"); + return CommonAlign; + } + + /// getFlags - Get the (implementation defined) symbol flags. + uint32_t getFlags() const { return Flags; } + + /// setFlags - Set the (implementation defined) symbol flags. + void setFlags(uint32_t Value) { Flags = Value; } + + /// getIndex - Get the (implementation defined) index. + uint64_t getIndex() const { return Index; } + + /// setIndex - Set the (implementation defined) index. + void setIndex(uint64_t Value) { Index = Value; } + + /// @} +}; + +// FIXME: This really doesn't belong here. See comments below. +struct IndirectSymbolData { + MCSymbol *Symbol; + MCSectionData *SectionData; +}; + +class MCAssembler { +public: + typedef iplist<MCSectionData> SectionDataListType; + typedef iplist<MCSymbolData> SymbolDataListType; + + typedef SectionDataListType::const_iterator const_iterator; + typedef SectionDataListType::iterator iterator; + + typedef SymbolDataListType::const_iterator const_symbol_iterator; + typedef SymbolDataListType::iterator symbol_iterator; + + typedef std::vector<IndirectSymbolData>::iterator indirect_symbol_iterator; + +private: + MCAssembler(const MCAssembler&); // DO NOT IMPLEMENT + void operator=(const MCAssembler&); // DO NOT IMPLEMENT + + MCContext &Context; + + raw_ostream &OS; + + iplist<MCSectionData> Sections; + + iplist<MCSymbolData> Symbols; + + std::vector<IndirectSymbolData> IndirectSymbols; + + unsigned SubsectionsViaSymbols : 1; + +private: + /// LayoutSection - Assign offsets and sizes to the fragments in the section + /// \arg SD, and update the section size. The section file offset should + /// already have been computed. + void LayoutSection(MCSectionData &SD); + +public: + /// Construct a new assembler instance. + /// + /// \arg OS - The stream to output to. + // + // FIXME: How are we going to parameterize this? Two obvious options are stay + // concrete and require clients to pass in a target like object. The other + // option is to make this abstract, and have targets provide concrete + // implementations as we do with AsmParser. + MCAssembler(MCContext &_Context, raw_ostream &OS); + ~MCAssembler(); + + MCContext &getContext() const { return Context; } + + /// Finish - Do final processing and write the object to the output stream. + void Finish(); + + // FIXME: This does not belong here. + bool getSubsectionsViaSymbols() const { + return SubsectionsViaSymbols; + } + void setSubsectionsViaSymbols(bool Value) { + SubsectionsViaSymbols = Value; + } + + /// @name Section List Access + /// @{ + + const SectionDataListType &getSectionList() const { return Sections; } + SectionDataListType &getSectionList() { return Sections; } + + iterator begin() { return Sections.begin(); } + const_iterator begin() const { return Sections.begin(); } + + iterator end() { return Sections.end(); } + const_iterator end() const { return Sections.end(); } + + size_t size() const { return Sections.size(); } + + /// @} + /// @name Symbol List Access + /// @{ + + const SymbolDataListType &getSymbolList() const { return Symbols; } + SymbolDataListType &getSymbolList() { return Symbols; } + + symbol_iterator symbol_begin() { return Symbols.begin(); } + const_symbol_iterator symbol_begin() const { return Symbols.begin(); } + + symbol_iterator symbol_end() { return Symbols.end(); } + const_symbol_iterator symbol_end() const { return Symbols.end(); } + + size_t symbol_size() const { return Symbols.size(); } + + /// @} + /// @name Indirect Symbol List Access + /// @{ + + // FIXME: This is a total hack, this should not be here. Once things are + // factored so that the streamer has direct access to the .o writer, it can + // disappear. + std::vector<IndirectSymbolData> &getIndirectSymbols() { + return IndirectSymbols; + } + + indirect_symbol_iterator indirect_symbol_begin() { + return IndirectSymbols.begin(); + } + + indirect_symbol_iterator indirect_symbol_end() { + return IndirectSymbols.end(); + } + + size_t indirect_symbol_size() const { return IndirectSymbols.size(); } + + /// @} +}; + +} // end namespace llvm + +#endif |
