#ifndef LLVM_MC_MCASMBACKEND_H
#define LLVM_MC_MCASMBACKEND_H
+#include "llvm/ADT/ArrayRef.h"
#include "llvm/MC/MCDirectives.h"
+#include "llvm/MC/MCDwarf.h"
#include "llvm/MC/MCFixup.h"
#include "llvm/Support/DataTypes.h"
#include "llvm/Support/ErrorHandling.h"
struct MCFixupKindInfo;
class MCFragment;
class MCInst;
-class MCInstFragment;
+class MCRelaxableFragment;
class MCObjectWriter;
class MCSection;
class MCValue;
class MCAsmBackend {
MCAsmBackend(const MCAsmBackend &) LLVM_DELETED_FUNCTION;
void operator=(const MCAsmBackend &) LLVM_DELETED_FUNCTION;
+
protected: // Can only create subclasses.
MCAsmBackend();
- unsigned HasReliableSymbolDifference : 1;
unsigned HasDataInCodeSupport : 1;
public:
virtual ~MCAsmBackend();
+ /// lifetime management
+ virtual void reset() {}
+
/// createObjectWriter - Create a new MCObjectWriter instance for use by the
/// assembler backend to emit the final object file.
virtual MCObjectWriter *createObjectWriter(raw_ostream &OS) const = 0;
/// createELFObjectTargetWriter - Create a new ELFObjectTargetWriter to enable
/// non-standard ELFObjectWriters.
- virtual MCELFObjectTargetWriter *createELFObjectTargetWriter() const {
+ virtual MCELFObjectTargetWriter *createELFObjectTargetWriter() const {
llvm_unreachable("createELFObjectTargetWriter is not supported by asm "
"backend");
}
- /// hasReliableSymbolDifference - Check whether this target implements
- /// accurate relocations for differences between symbols. If not, differences
- /// between symbols will always be relocatable expressions and any references
- /// to temporary symbols will be assumed to be in the same atom, unless they
- /// reside in a different section.
- ///
- /// This should always be true (since it results in fewer relocations with no
- /// loss of functionality), but is currently supported as a way to maintain
- /// exact object compatibility with Darwin 'as' (on non-x86_64). It should
- /// eventually should be eliminated.
- bool hasReliableSymbolDifference() const {
- return HasReliableSymbolDifference;
- }
-
/// hasDataInCodeSupport - Check whether this target implements data-in-code
/// markers. If not, data region directives will be ignored.
- bool hasDataInCodeSupport() const {
- return HasDataInCodeSupport;
- }
+ bool hasDataInCodeSupport() const { return HasDataInCodeSupport; }
/// doesSectionRequireSymbols - Check whether the given section requires that
/// all symbols (even temporaries) have symbol table entries.
virtual void processFixupValue(const MCAssembler &Asm,
const MCAsmLayout &Layout,
const MCFixup &Fixup, const MCFragment *DF,
- MCValue &Target, uint64_t &Value,
+ const MCValue &Target, uint64_t &Value,
bool &IsResolved) {}
- /// @}
-
/// applyFixup - Apply the \p Value for given \p Fixup into the provided
/// data fragment, at the offset specified by the fixup and following the
/// fixup kind as appropriate.
virtual void applyFixup(const MCFixup &Fixup, char *Data, unsigned DataSize,
- uint64_t Value) const = 0;
+ uint64_t Value, bool IsPCRel) const = 0;
/// @}
/// fixupNeedsRelaxation - Target specific predicate for whether a given
/// fixup requires the associated instruction to be relaxed.
- virtual bool fixupNeedsRelaxation(const MCFixup &Fixup,
- uint64_t Value,
- const MCInstFragment *DF,
+ virtual bool fixupNeedsRelaxation(const MCFixup &Fixup, uint64_t Value,
+ const MCRelaxableFragment *DF,
const MCAsmLayout &Layout) const = 0;
/// RelaxInstruction - Relax the instruction in the given fragment to the next
/// handleAssemblerFlag - Handle any target-specific assembler flags.
/// By default, do nothing.
virtual void handleAssemblerFlag(MCAssemblerFlag Flag) {}
+
+ /// \brief Generate the compact unwind encoding for the CFI instructions.
+ virtual uint32_t
+ generateCompactUnwindEncoding(ArrayRef<MCCFIInstruction>) const {
+ return 0;
+ }
};
} // End llvm namespace