llvm-6502/include/llvm/Metadata.h
Eric Christopher f32a960fd3 Add a way to replace a field inside a metadata node. This can be
used to incrementally update a created node without needing a
temporary node and RAUW.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150571 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-15 09:09:29 +00:00

240 lines
8.1 KiB
C++

//===-- llvm/Metadata.h - Metadata definitions ------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
/// @file
/// This file contains the declarations for metadata subclasses.
/// They represent the different flavors of metadata that live in LLVM.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_METADATA_H
#define LLVM_METADATA_H
#include "llvm/Value.h"
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/FoldingSet.h"
#include "llvm/ADT/ilist_node.h"
namespace llvm {
class Constant;
class Instruction;
class LLVMContext;
class Module;
template <typename T> class SmallVectorImpl;
template<typename ValueSubClass, typename ItemParentClass>
class SymbolTableListTraits;
//===----------------------------------------------------------------------===//
/// MDString - a single uniqued string.
/// These are used to efficiently contain a byte sequence for metadata.
/// MDString is always unnamed.
class MDString : public Value {
virtual void anchor();
MDString(const MDString &); // DO NOT IMPLEMENT
StringRef Str;
explicit MDString(LLVMContext &C, StringRef S);
public:
static MDString *get(LLVMContext &Context, StringRef Str);
static MDString *get(LLVMContext &Context, const char *Str) {
return get(Context, Str ? StringRef(Str) : StringRef());
}
StringRef getString() const { return Str; }
unsigned getLength() const { return (unsigned)Str.size(); }
typedef StringRef::iterator iterator;
/// begin() - Pointer to the first byte of the string.
///
iterator begin() const { return Str.begin(); }
/// end() - Pointer to one byte past the end of the string.
///
iterator end() const { return Str.end(); }
/// Methods for support type inquiry through isa, cast, and dyn_cast:
static inline bool classof(const MDString *) { return true; }
static bool classof(const Value *V) {
return V->getValueID() == MDStringVal;
}
};
class MDNodeOperand;
//===----------------------------------------------------------------------===//
/// MDNode - a tuple of other values.
class MDNode : public Value, public FoldingSetNode {
MDNode(const MDNode &); // DO NOT IMPLEMENT
void operator=(const MDNode &); // DO NOT IMPLEMENT
friend class MDNodeOperand;
friend class LLVMContextImpl;
/// NumOperands - This many 'MDNodeOperand' items are co-allocated onto the
/// end of this MDNode.
unsigned NumOperands;
// Subclass data enums.
enum {
/// FunctionLocalBit - This bit is set if this MDNode is function local.
/// This is true when it (potentially transitively) contains a reference to
/// something in a function, like an argument, basicblock, or instruction.
FunctionLocalBit = 1 << 0,
/// NotUniquedBit - This is set on MDNodes that are not uniqued because they
/// have a null operand.
NotUniquedBit = 1 << 1,
/// DestroyFlag - This bit is set by destroy() so the destructor can assert
/// that the node isn't being destroyed with a plain 'delete'.
DestroyFlag = 1 << 2
};
// FunctionLocal enums.
enum FunctionLocalness {
FL_Unknown = -1,
FL_No = 0,
FL_Yes = 1
};
/// replaceOperand - Replace each instance of F from the operand list of this
/// node with T.
void replaceOperand(MDNodeOperand *Op, Value *NewVal);
~MDNode();
MDNode(LLVMContext &C, ArrayRef<Value*> Vals, bool isFunctionLocal);
static MDNode *getMDNode(LLVMContext &C, ArrayRef<Value*> Vals,
FunctionLocalness FL, bool Insert = true);
public:
// Constructors and destructors.
static MDNode *get(LLVMContext &Context, ArrayRef<Value*> Vals);
// getWhenValsUnresolved - Construct MDNode determining function-localness
// from isFunctionLocal argument, not by analyzing Vals.
static MDNode *getWhenValsUnresolved(LLVMContext &Context,
ArrayRef<Value*> Vals,
bool isFunctionLocal);
static MDNode *getIfExists(LLVMContext &Context, ArrayRef<Value*> Vals);
/// getTemporary - Return a temporary MDNode, for use in constructing
/// cyclic MDNode structures. A temporary MDNode is not uniqued,
/// may be RAUW'd, and must be manually deleted with deleteTemporary.
static MDNode *getTemporary(LLVMContext &Context, ArrayRef<Value*> Vals);
/// deleteTemporary - Deallocate a node created by getTemporary. The
/// node must not have any users.
static void deleteTemporary(MDNode *N);
/// replaceOperandWith - Replace a specific operand.
void replaceOperandWith(unsigned i, Value *NewVal);
/// getOperand - Return specified operand.
Value *getOperand(unsigned i) const;
/// getNumOperands - Return number of MDNode operands.
unsigned getNumOperands() const { return NumOperands; }
/// isFunctionLocal - Return whether MDNode is local to a function.
bool isFunctionLocal() const {
return (getSubclassDataFromValue() & FunctionLocalBit) != 0;
}
// getFunction - If this metadata is function-local and recursively has a
// function-local operand, return the first such operand's parent function.
// Otherwise, return null. getFunction() should not be used for performance-
// critical code because it recursively visits all the MDNode's operands.
const Function *getFunction() const;
/// Profile - calculate a unique identifier for this MDNode to collapse
/// duplicates
void Profile(FoldingSetNodeID &ID) const;
/// Methods for support type inquiry through isa, cast, and dyn_cast:
static inline bool classof(const MDNode *) { return true; }
static bool classof(const Value *V) {
return V->getValueID() == MDNodeVal;
}
private:
// destroy - Delete this node. Only when there are no uses.
void destroy();
bool isNotUniqued() const {
return (getSubclassDataFromValue() & NotUniquedBit) != 0;
}
void setIsNotUniqued();
// Shadow Value::setValueSubclassData with a private forwarding method so that
// any future subclasses cannot accidentally use it.
void setValueSubclassData(unsigned short D) {
Value::setValueSubclassData(D);
}
};
//===----------------------------------------------------------------------===//
/// NamedMDNode - a tuple of MDNodes. Despite its name, a NamedMDNode isn't
/// itself an MDNode. NamedMDNodes belong to modules, have names, and contain
/// lists of MDNodes.
class NamedMDNode : public ilist_node<NamedMDNode> {
friend class SymbolTableListTraits<NamedMDNode, Module>;
friend struct ilist_traits<NamedMDNode>;
friend class LLVMContextImpl;
friend class Module;
NamedMDNode(const NamedMDNode &); // DO NOT IMPLEMENT
std::string Name;
Module *Parent;
void *Operands; // SmallVector<TrackingVH<MDNode>, 4>
void setParent(Module *M) { Parent = M; }
explicit NamedMDNode(const Twine &N);
public:
/// eraseFromParent - Drop all references and remove the node from parent
/// module.
void eraseFromParent();
/// dropAllReferences - Remove all uses and clear node vector.
void dropAllReferences();
/// ~NamedMDNode - Destroy NamedMDNode.
~NamedMDNode();
/// getParent - Get the module that holds this named metadata collection.
inline Module *getParent() { return Parent; }
inline const Module *getParent() const { return Parent; }
/// getOperand - Return specified operand.
MDNode *getOperand(unsigned i) const;
/// getNumOperands - Return the number of NamedMDNode operands.
unsigned getNumOperands() const;
/// addOperand - Add metadata operand.
void addOperand(MDNode *M);
/// getName - Return a constant reference to this named metadata's name.
StringRef getName() const;
/// print - Implement operator<< on NamedMDNode.
void print(raw_ostream &ROS, AssemblyAnnotationWriter *AAW = 0) const;
/// dump() - Allow printing of NamedMDNodes from the debugger.
void dump() const;
};
} // end llvm namespace
#endif