Add a header patterned after MCDwarf.h for supporting Win64 exception handling

under MC.

llvm-svn: 131593

include/llvm/MC/MCWin64EH.h

@@ -0,0 +1,91 @@
+//===- MCWin64EH.h - Machine Code Win64 EH support --------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains the declaration of the MCDwarfFile to support the dwarf
+// .file directive and the .loc directive.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_MC_MCWIN64EH_H
+#define LLVM_MC_MCWIN64EH_H
+
+#include "llvm/CodeGen/MachineLocation.h" // FIXME
+#include "llvm/Support/Win64EH.h"
+#include <vector>
+
+namespace llvm {
+  class MCStreamer;
+  class MCSymbol;
+
+  class MCWin64EHInstruction {
+  public:
+    typedef Win64EH::UnwindOpcodes OpType;
+  private:
+    OpType Operation;
+    unsigned Offset;
+    MachineLocation Destination;
+    MachineLocation Source;
+  public:
+    MCWin64EHInstruction(OpType Op, unsigned Register)
+      : Operation(Op), Offset(0), Destination(0), Source(S) {
+      assert(Op == Win64EH::UOP_PushNonVol);
+    }
+    MCWin64EHInstruction(unsigned Size)
+      : Operation(Size>128 ? Win64EH::UOP_AllocLarge : Win64EH::UOP_AllocSmall),
+        Offset(size) { }
+    MCWin64EHInstruction(unsigned Register, unsigned Off)
+      : Operation(Win64EH::UOP_SetFPReg), Offset(Off), Destination(Register) { }
+    MCWin64EHInstruction(OpType Op, const MachineLocation &D,
+                         unsigned S)
+      : Operation(Op), Destination(D), Source(S) {
+      assert(Op == Win64EH::UOP_SaveNonVol ||
+             Op == Win64EH::UOP_SaveNonVolBig ||
+             Op == Win64EH::UOP_SaveXMM128 ||
+             Op == Win64EH::UOP_SaveXMM128Big);
+    }
+    MCWin64EHInstruction(OpType Op, bool Code)
+      : Operation(Op), Offset(Code ? 1 : 0) {
+      assert(Op == Win64EH::UOP_PushMachFrame);
+    }
+    OpType getOperation() const { return Operation; }
+    unsigned getOffset() const { return Offset; }
+    unsigned getSize() const { return Offset; }
+    bool isPushCodeFrame() const { return Offset == 1; }
+    const MachineLocation &getDestination() const { return Destination; }
+    const MachineLocation &getSource() const { return Source; }
+  };
+
+  struct MCWin64EHUnwindInfo {
+    MCWin64EHUnwindInfo() : Begin(0), End(0), ExceptionHandler(0), Lsda(0),
+                            Function(0), UnwindOnly(false), LsdaSize(0),
+                            PrologSize(0), LastFrameInst(-1), Chained(false)
+                            Instructions() {}
+    MCSymbol *Begin;
+    MCSymbol *End;
+    const MCSymbol *ExceptionHandler;
+    const MCSymbol *Lsda;
+    const MCSymbol *Function;
+    bool UnwindOnly;
+    unsigned LsdaSize;
+    unsigned PrologSize;
+    int LastFrameInst;
+    bool Chained;
+    std::vector<MCWin64EHInstruction> Instructions;
+  };
+
+  class MCWin64EHUnwindEmitter {
+  public:
+    //
+    // This emits the unwind info section (.xdata in PE/COFF).
+    //
+    static void Emit(MCStreamer &streamer);
+  };
+} // end namespace llvm
+
+#endif