#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 MCSectionData;
+class MCSymbol;
class MCSymbolData;
/// 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 {
+public:
+ typedef llvm::SmallVectorImpl<MCSectionData*>::const_iterator const_iterator;
+ typedef llvm::SmallVectorImpl<MCSectionData*>::iterator iterator;
+
private:
MCAssembler &Assembler;
+ /// List of sections in layout order.
+ llvm::SmallVector<MCSectionData*, 16> 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<const MCSectionData*, MCFragment*> 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;
+
+ /// \brief Compute the amount of padding required before this fragment to
+ /// obey bundling restrictions.
+ uint64_t computeBundlePadding(const MCFragment *F,
+ uint64_t FOffset, uint64_t FSize);
+
public:
- MCAsmLayout(MCAssembler &_Assembler) : Assembler(_Assembler) {}
+ MCAsmLayout(MCAssembler &_Assembler);
/// Get the assembler object this is a layout for.
MCAssembler &getAssembler() const { return Assembler; }
- uint64_t getFragmentAddress(const MCFragment *F) const;
+ /// \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<MCSectionData*> &getSectionOrder() {
+ return SectionOrder;
+ }
+ const llvm::SmallVectorImpl<MCSectionData*> &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 MCSectionData *SD) 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 MCSectionData *SD) const;
+
+ /// \brief Get the offset of the given symbol, as computed in the current
+ /// layout.
+ /// \result True on success.
+ bool getSymbolOffset(const MCSymbolData *SD, uint64_t &Val) const;
- uint64_t getSectionAddress(const MCSectionData *SD) const;
+ /// \brief Variant that reports a fatal error if the offset is not computable.
+ uint64_t getSymbolOffset(const MCSymbolData *SD) const;
- uint64_t getSymbolAddress(const MCSymbolData *SD) const;
+ /// \brief If this symbol is equivalent to A + Constant, return A.
+ const MCSymbol *getBaseSymbol(const MCSymbol &Symbol) const;
- void setSectionAddress(MCSectionData *SD, uint64_t Value);
+ /// @}
};
} // end namespace llvm