class ValueSymbolTable;
class TypeSymbolTable;
template<typename ValueTy> class StringMapEntry;
+template <typename ValueTy = Value>
+class AssertingVH;
typedef StringMapEntry<Value*> ValueName;
class raw_ostream;
class AssemblyAnnotationWriter;
+class ValueHandleBase;
//===----------------------------------------------------------------------===//
// Value Class
/// automatically updates the module's symbol table.
///
/// Every value has a "use list" that keeps track of which other Values are
-/// using this Value.
+/// using this Value. A Value can also have an arbitrary number of ValueHandle
+/// objects that watch it and listen to RAUW and Destroy events see
+/// llvm/Support/ValueHandle.h for details.
+///
/// @brief LLVM Value Representation
class Value {
- const unsigned short SubclassID; // Subclass identifier (for isa/dyn_cast)
+ const unsigned char SubclassID; // Subclass identifier (for isa/dyn_cast)
+ unsigned char HasValueHandle : 1; // Has a ValueHandle pointing to this?
protected:
+ /// SubclassOptionalData - This member is similar to SubclassData, however it
+ /// is for holding information which may be used to aid optimization, but
+ /// which may be cleared to zero without affecting conservative
+ /// interpretation.
+ unsigned char SubclassOptionalData : 7;
+
/// SubclassData - This member is defined by this class, but is not used for
/// anything. Subclasses can use it to hold whatever state they find useful.
/// This field is initialized to zero by the ctor.
friend class ValueSymbolTable; // Allow ValueSymbolTable to directly mod Name.
friend class SymbolTable; // Allow SymbolTable to directly poke Name.
+ friend class ValueHandleBase;
ValueName *Name;
void operator=(const Value &); // Do not implement
// Only use when in type resolution situations!
void uncheckedReplaceAllUsesWith(Value *V);
+ /// clearOptionalData - Clear any optional optimization data from this Value.
+ /// Transformation passes must call this method whenever changing the IR
+ /// in a way that would affect the values produced by this Value, unless
+ /// it takes special care to ensure correctness in some other way.
+ void clearOptionalData() { SubclassOptionalData = 0; }
+
//----------------------------------------------------------------------
// Methods for handling the chain of uses of this Value.
//
ConstantStructVal, // This is an instance of ConstantStruct
ConstantVectorVal, // This is an instance of ConstantVector
ConstantPointerNullVal, // This is an instance of ConstantPointerNull
+ MDStringVal, // This is an instance of MDString
+ MDNodeVal, // This is an instance of MDNode
InlineAsmVal, // This is an instance of InlineAsm
PseudoSourceValueVal, // This is an instance of PseudoSourceValue
InstructionVal, // This is an instance of Instruction
// Markers:
ConstantFirstVal = FunctionVal,
- ConstantLastVal = ConstantPointerNullVal
+ ConstantLastVal = MDNodeVal
};
/// getValueID - Return an ID for the concrete type of this object. This is
return isa<GlobalVariable>(Val) || isa<Function>(Val) ||
isa<GlobalAlias>(Val);
}
+
+
+// Value* is only 4-byte aligned.
+template<>
+class PointerLikeTypeTraits<Value*> {
+ typedef Value* PT;
+public:
+ static inline void *getAsVoidPointer(PT P) { return P; }
+ static inline PT getFromVoidPointer(void *P) {
+ return static_cast<PT>(P);
+ }
+ enum { NumLowBitsAvailable = 2 };
+};
} // End llvm namespace