X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;ds=sidebyside;f=include%2Fllvm%2FMC%2FMCAsmLayout.h;h=1b20d5b804a4ba546ddf2bc541421600848d1e5d;hb=380de5479cba79ad9c55e80f53252e968390cc8e;hp=d448625320cd99aa759b9dc2a1c2426e8de8288e;hpb=18ff2cced7e08ac76d8d5bcff8160a5f9a109cbb;p=oota-llvm.git diff --git a/include/llvm/MC/MCAsmLayout.h b/include/llvm/MC/MCAsmLayout.h index d448625320c..1b20d5b804a 100644 --- a/include/llvm/MC/MCAsmLayout.h +++ b/include/llvm/MC/MCAsmLayout.h @@ -10,25 +10,96 @@ #ifndef LLVM_MC_MCASMLAYOUT_H #define LLVM_MC_MCASMLAYOUT_H +#include "llvm/ADT/DenseMap.h" +#include "llvm/ADT/SmallVector.h" + namespace llvm { class MCAssembler; +class MCFragment; +class MCSection; +class MCSymbol; /// Encapsulates the layout of an assembly file at a particular point in time. /// -/// Assembly may requiring compute multiple layouts for a particular assembly +/// Assembly may require computing multiple layouts for a particular assembly /// file as part of the relaxation process. This class encapsulates the layout /// at a single point in time in such a way that it is always possible to -/// efficiently compute the exact addresses of any symbol in the assembly file, +/// efficiently compute the exact address of any symbol in the assembly file, /// even during the relaxation process. class MCAsmLayout { -private: MCAssembler &Assembler; + /// List of sections in layout order. + llvm::SmallVector SectionOrder; + + /// The last fragment which was laid out, or 0 if nothing has been laid + /// out. Fragments are always laid out in order, so all fragments with a + /// lower ordinal will be valid. + mutable DenseMap LastValidFragment; + + /// \brief Make sure that the layout for the given fragment is valid, lazily + /// computing it if necessary. + void ensureValid(const MCFragment *F) const; + + /// \brief Is the layout for this fragment valid? + bool isFragmentValid(const MCFragment *F) const; + public: - MCAsmLayout(MCAssembler &_Assembler) : Assembler(_Assembler) {} + MCAsmLayout(MCAssembler &Assembler); /// Get the assembler object this is a layout for. - MCAssembler &getAssembler() { return Assembler; } + MCAssembler &getAssembler() const { return Assembler; } + + /// \brief Invalidate the fragments starting with F because it has been + /// resized. The fragment's size should have already been updated, but + /// its bundle padding will be recomputed. + void invalidateFragmentsFrom(MCFragment *F); + + /// \brief Perform layout for a single fragment, assuming that the previous + /// fragment has already been laid out correctly, and the parent section has + /// been initialized. + void layoutFragment(MCFragment *Fragment); + + /// \name Section Access (in layout order) + /// @{ + + llvm::SmallVectorImpl &getSectionOrder() { return SectionOrder; } + const llvm::SmallVectorImpl &getSectionOrder() const { + return SectionOrder; + } + + /// @} + /// \name Fragment Layout Data + /// @{ + + /// \brief Get the offset of the given fragment inside its containing section. + uint64_t getFragmentOffset(const MCFragment *F) const; + + /// @} + /// \name Utility Functions + /// @{ + + /// \brief Get the address space size of the given section, as it effects + /// layout. This may differ from the size reported by \see getSectionSize() by + /// not including section tail padding. + uint64_t getSectionAddressSize(const MCSection *Sec) const; + + /// \brief Get the data size of the given section, as emitted to the object + /// file. This may include additional padding, or be 0 for virtual sections. + uint64_t getSectionFileSize(const MCSection *Sec) const; + + /// \brief Get the offset of the given symbol, as computed in the current + /// layout. + /// \return True on success. + bool getSymbolOffset(const MCSymbol &S, uint64_t &Val) const; + + /// \brief Variant that reports a fatal error if the offset is not computable. + uint64_t getSymbolOffset(const MCSymbol &S) const; + + /// \brief If this symbol is equivalent to A + Constant, return A. + const MCSymbol *getBaseSymbol(const MCSymbol &Symbol) const; + + /// @} }; } // end namespace llvm