There are two reasons why we might want to use

[oota-llvm.git] / include / llvm / MC / MCCodeEmitter.h

diff --git a/include/llvm/MC/MCCodeEmitter.h b/include/llvm/MC/MCCodeEmitter.h
index 6cca95b826ada108c4abb2aaaf039fec9b46e7e0..eac06ede2abbbdaa39a4d12e446409d9b41cecb9 100644 (file)
--- a/include/llvm/MC/MCCodeEmitter.h
+++ b/include/llvm/MC/MCCodeEmitter.h
@@ -10,23 +10,69 @@
 #ifndef LLVM_MC_MCCODEEMITTER_H
 #define LLVM_MC_MCCODEEMITTER_H
 
+#include "llvm/MC/MCFixup.h"
+
+#include <cassert>
+
 namespace llvm {
+class MCExpr;
 class MCInst;
 class raw_ostream;
+template<typename T> class SmallVectorImpl;
+
+/// MCFixupKindInfo - Target independent information on a fixup kind.
+struct MCFixupKindInfo {
+  enum FixupKindFlags {
+    /// Is this fixup kind PCrelative? This is used by the assembler backend to
+    /// evaluate fixup values in a target independent manner when possible.
+    FKF_IsPCRel = (1 << 0)
+  };
+
+  /// A target specific name for the fixup kind. The names will be unique for
+  /// distinct kinds on any given target.
+  const char *Name;
+
+  /// The bit offset to write the relocation into.
+  //
+  // FIXME: These two fields are under-specified and not general enough, but it
+  // covers many things. It's enough to let the AsmStreamer pretty-print
+  // the encoding.
+  unsigned TargetOffset;
+
+  /// The number of bits written by this fixup. The bits are assumed to be
+  /// contiguous.
+  unsigned TargetSize;
+
+  /// Flags describing additional information on this fixup kind.
+  unsigned Flags;
+};
 
 /// MCCodeEmitter - Generic instruction encoding interface.
 class MCCodeEmitter {
+private:
   MCCodeEmitter(const MCCodeEmitter &);   // DO NOT IMPLEMENT
   void operator=(const MCCodeEmitter &);  // DO NOT IMPLEMENT
 protected: // Can only create subclasses.
   MCCodeEmitter();
- 
+
 public:
   virtual ~MCCodeEmitter();
 
+  /// @name Target Independent Fixup Information
+  /// @{
+
+  /// getNumFixupKinds - Get the number of target specific fixup kinds.
+  virtual unsigned getNumFixupKinds() const = 0;
+
+  /// getFixupKindInfo - Get information on a fixup kind.
+  virtual const MCFixupKindInfo &getFixupKindInfo(MCFixupKind Kind) const;
+
+  /// @}
+
   /// EncodeInstruction - Encode the given \arg Inst to bytes on the output
   /// stream \arg OS.
-  virtual void EncodeInstruction(const MCInst &Inst, raw_ostream &OS) = 0;
+  virtual void EncodeInstruction(const MCInst &Inst, raw_ostream &OS,
+                                 SmallVectorImpl<MCFixup> &Fixups) const = 0;
 };
 
 } // End llvm namespace