This is a major cleanup of the instruction metadata interfaces that

I asked Devang to do back on Sep 27.  Instead of going through the
MetadataContext class with methods like getMD() and getMDs(), just
ask the instruction directly for its metadata with getMetadata()
and getAllMetadata().

This includes a variety of other fixes and improvements: previously
all Value*'s were bloated because the HasMetadata bit was thrown into
value, adding a 9th bit to a byte.  Now this is properly sunk down to
the Instruction class (the only place where it makes sense) and it
will be folded away somewhere soon.

This also fixes some confusion in getMDs and its clients about 
whether the returned list is indexed by the MDID or densely packed.
This is now returned sorted and densely packed and the comments make
this clear.

This introduces a number of fixme's which I'll follow up on.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92235 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 61 insertions, 6 deletions

diff --git a/include/llvm/Instruction.h b/include/llvm/Instruction.h
index c4c746a49f..6cfe0a1ca7 100644
--- a/include/llvm/Instruction.h
+++ b/include/llvm/Instruction.h
@@ -21,6 +21,8 @@
 namespace llvm {
 
 class LLVMContext;
+class MDNode;
+class MetadataContextImpl;
 
 template<typename ValueSubClass, typename ItemParentClass>
   class SymbolTableListTraits;
@@ -30,6 +32,10 @@ class Instruction : public User, public ilist_node<Instruction> {
   Instruction(const Instruction &);        // Do not implement
 
   BasicBlock *Parent;
+  
+  // FIXME: Bitfieldize this.
+  bool HasMetadata;
+  friend class MetadataContextImpl;
 
   friend class SymbolTableListTraits<Instruction, BasicBlock>;
   void setParent(BasicBlock *P);
@@ -74,19 +80,19 @@ public:
   /// MovePos.
   void moveBefore(Instruction *MovePos);
 
-  // ---------------------------------------------------------------------------
-  /// Subclass classification... getOpcode() returns a member of
-  /// one of the enums that is coming soon (down below)...
-  ///
+  //===--------------------------------------------------------------------===//
+  // Subclass classification.
+  //===--------------------------------------------------------------------===//
+  
+  /// getOpcode() returns a member of one of the enums like Instruction::Add.
   unsigned getOpcode() const { return getValueID() - InstructionVal; }
+  
   const char *getOpcodeName() const { return getOpcodeName(getOpcode()); }
   bool isTerminator() const { return isTerminator(getOpcode()); }
   bool isBinaryOp() const { return isBinaryOp(getOpcode()); }
   bool isShift() { return isShift(getOpcode()); }
   bool isCast() const { return isCast(getOpcode()); }
   
-  
-  
   static const char* getOpcodeName(unsigned OpCode);
 
   static inline bool isTerminator(unsigned OpCode) {
@@ -118,6 +124,55 @@ public:
     return OpCode >= CastOpsBegin && OpCode < CastOpsEnd;
   }
 
+  //===--------------------------------------------------------------------===//
+  // Metadata manipulation.
+  //===--------------------------------------------------------------------===//
+  
+  /// hasMetadata() - Return true if this instruction has any metadata attached
+  /// to it.
+  bool hasMetadata() const {
+    return HasMetadata;
+  }
+  
+  /// getMetadata - Get the metadata of given kind attached to this Instruction.
+  /// If the metadata is not found then return null.
+  MDNode *getMetadata(unsigned KindID) const {
+    if (!hasMetadata()) return 0;
+    return getMetadataImpl(KindID);
+  }
+  
+  /// getMetadata - Get the metadata of given kind attached to this Instruction.
+  /// If the metadata is not found then return null.
+  MDNode *getMetadata(const char *Kind) const {
+    if (!hasMetadata()) return 0;
+    return getMetadataImpl(Kind);
+  }
+  
+  /// getAllMetadata - Get all metadata attached to this Instruction.  The first
+  /// element of each pair returned is the KindID, the second element is the
+  /// metadata value.  This list is returned sorted by the KindID.
+  void getAllMetadata(SmallVectorImpl<std::pair<unsigned, MDNode*> > &MDs)const{
+    if (hasMetadata())
+      getAllMetadataImpl(MDs);
+  }
+  
+  /// setMetadata - Set the metadata of of the specified kind to the specified
+  /// node.  This updates/replaces metadata if already present, or removes it if
+  /// Node is null.
+  void setMetadata(unsigned KindID, MDNode *Node);
+  void setMetadata(const char *Kind, MDNode *Node);
+
+private:
+  // These are all implemented in Metadata.cpp.
+  MDNode *getMetadataImpl(unsigned KindID) const;
+  MDNode *getMetadataImpl(const char *Kind) const;
+  void getAllMetadataImpl(SmallVectorImpl<std::pair<unsigned,MDNode*> > &)const;
+public:
+  //===--------------------------------------------------------------------===//
+  // Predicates and helper methods.
+  //===--------------------------------------------------------------------===//
+  
+  
   /// isAssociative - Return true if the instruction is associative:
   ///
   ///   Associative operators satisfy:  x op (y op z) === (x op y) op z