Refactor MCInstFragment and MCDataFragment to adhere to a common interface,

which removes code duplication and prepares the ground for future additions.

Full discussion:
http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20121203/158233.html



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169626 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 50 insertions, 45 deletions

diff --git a/include/llvm/MC/MCAssembler.h b/include/llvm/MC/MCAssembler.h
index 266e0c7f48..a308030ff6 100644
--- a/include/llvm/MC/MCAssembler.h
+++ b/include/llvm/MC/MCAssembler.h
@@ -102,7 +102,35 @@ public:
   void dump();
 };
 
-class MCDataFragment : public MCFragment {
+class MCEncodedFragment : public MCFragment {
+  virtual void anchor();
+public:
+  MCEncodedFragment(MCFragment::FragmentType FType, MCSectionData *SD = 0)
+    : MCFragment(FType, SD) {
+  }
+  virtual ~MCEncodedFragment();
+
+  typedef SmallVectorImpl<MCFixup>::const_iterator const_fixup_iterator;
+  typedef SmallVectorImpl<MCFixup>::iterator fixup_iterator;
+
+  virtual SmallString<32> &getContents() = 0;
+  virtual const SmallString<32> &getContents() const = 0;
+
+  virtual SmallVectorImpl<MCFixup> &getFixups() = 0;
+  virtual const SmallVectorImpl<MCFixup> &getFixups() const = 0;
+
+  virtual fixup_iterator fixup_begin() = 0;
+  virtual const_fixup_iterator fixup_begin() const  = 0;
+  virtual fixup_iterator fixup_end() = 0;
+  virtual const_fixup_iterator fixup_end() const = 0;
+
+  static bool classof(const MCFragment *F) {
+    MCFragment::FragmentType Kind = F->getKind();
+    return Kind == MCFragment::FT_Inst || Kind == MCFragment::FT_Data;
+  }
+};
+
+class MCDataFragment : public MCEncodedFragment {
   virtual void anchor();
   SmallString<32> Contents;
 
@@ -110,27 +138,19 @@ class MCDataFragment : public MCFragment {
   SmallVector<MCFixup, 4> Fixups;
 
 public:
-  typedef SmallVectorImpl<MCFixup>::const_iterator const_fixup_iterator;
-  typedef SmallVectorImpl<MCFixup>::iterator fixup_iterator;
-
-public:
-  MCDataFragment(MCSectionData *SD = 0) : MCFragment(FT_Data, SD) {}
-
-  /// @name Accessors
-  /// @{
+  MCDataFragment(MCSectionData *SD = 0)
+    : MCEncodedFragment(FT_Data, SD) {
+  }
 
   SmallString<32> &getContents() { return Contents; }
   const SmallString<32> &getContents() const { return Contents; }
 
-  /// @}
-  /// @name Fixup Access
-  /// @{
+  SmallVectorImpl<MCFixup> &getFixups() {
+    return Fixups;
+  }
 
-  void addFixup(MCFixup Fixup) {
-    // Enforce invariant that fixups are in offset order.
-    assert((Fixups.empty() || Fixup.getOffset() >= Fixups.back().getOffset()) &&
-           "Fixups must be added in order!");
-    Fixups.push_back(Fixup);
+  const SmallVectorImpl<MCFixup> &getFixups() const {
+    return Fixups;
   }
 
   fixup_iterator fixup_begin() { return Fixups.begin(); }
@@ -139,55 +159,42 @@ public:
   fixup_iterator fixup_end() {return Fixups.end();}
   const_fixup_iterator fixup_end() const {return Fixups.end();}
 
-  /// @}
-
   static bool classof(const MCFragment *F) {
     return F->getKind() == MCFragment::FT_Data;
   }
 };
 
-// FIXME: This current incarnation of MCInstFragment doesn't make much sense, as
-// it is almost entirely a duplicate of MCDataFragment. If we decide to stick
-// with this approach (as opposed to making MCInstFragment a very light weight
-// object with just the MCInst and a code size, then we should just change
-// MCDataFragment to have an optional MCInst at its end.
-class MCInstFragment : public MCFragment {
+class MCInstFragment : public MCEncodedFragment {
   virtual void anchor();
 
   /// Inst - The instruction this is a fragment for.
   MCInst Inst;
 
-  /// Code - Binary data for the currently encoded instruction.
-  SmallString<8> Code;
+  /// Contents - Binary data for the currently encoded instruction.
+  SmallString<32> Contents;
 
   /// Fixups - The list of fixups in this fragment.
   SmallVector<MCFixup, 1> Fixups;
 
 public:
-  typedef SmallVectorImpl<MCFixup>::const_iterator const_fixup_iterator;
-  typedef SmallVectorImpl<MCFixup>::iterator fixup_iterator;
-
-public:
   MCInstFragment(const MCInst &_Inst, MCSectionData *SD = 0)
-    : MCFragment(FT_Inst, SD), Inst(_Inst) {
+    : MCEncodedFragment(FT_Inst, SD), Inst(_Inst) {
   }
 
-  /// @name Accessors
-  /// @{
-
-  SmallVectorImpl<char> &getCode() { return Code; }
-  const SmallVectorImpl<char> &getCode() const { return Code; }
+  SmallString<32> &getContents() { return Contents; }
+  const SmallString<32> &getContents() const { return Contents; }
 
-  unsigned getInstSize() const { return Code.size(); }
+  unsigned getInstSize() const { return Contents.size(); }
   const MCInst &getInst() const { return Inst; }
   void setInst(const MCInst& Value) { Inst = Value; }
 
-  /// @}
-  /// @name Fixup Access
-  /// @{
+  SmallVectorImpl<MCFixup> &getFixups() {
+    return Fixups;
+  }
 
-  SmallVectorImpl<MCFixup> &getFixups() { return Fixups; }
-  const SmallVectorImpl<MCFixup> &getFixups() const { return Fixups; }
+  const SmallVectorImpl<MCFixup> &getFixups() const {
+    return Fixups;
+  }
 
   fixup_iterator fixup_begin() { return Fixups.begin(); }
   const_fixup_iterator fixup_begin() const { return Fixups.begin(); }
@@ -195,8 +202,6 @@ public:
   fixup_iterator fixup_end() {return Fixups.end();}
   const_fixup_iterator fixup_end() const {return Fixups.end();}
 
-  /// @}
-
   static bool classof(const MCFragment *F) {
     return F->getKind() == MCFragment::FT_Inst;
   }