//===- llvm/Analysis/ValueNumbering.h - Value #'ing Interface ---*- C++ -*-===//
-//
+//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
-//
+//
//===----------------------------------------------------------------------===//
//
// This file defines the abstract ValueNumbering interface, which is used as the
#define LLVM_ANALYSIS_VALUE_NUMBERING_H
#include <vector>
+#include "llvm/Pass.h"
+
+namespace llvm {
+
class Value;
+class Instruction;
struct ValueNumbering {
+ virtual ~ValueNumbering(); // We want to be subclassed
/// getEqualNumberNodes - Return nodes with the same value number as the
/// specified Value. This fills in the argument vector with any equal values.
virtual void getEqualNumberNodes(Value *V1,
std::vector<Value*> &RetVals) const = 0;
- virtual ~ValueNumbering(); // We want to be subclassed
+ ///===-------------------------------------------------------------------===//
+ /// Interfaces to update value numbering analysis information as the client
+ /// changes the program.
+ ///
+
+ /// deleteValue - This method should be called whenever an LLVM Value is
+ /// deleted from the program, for example when an instruction is found to be
+ /// redundant and is eliminated.
+ ///
+ virtual void deleteValue(Value *V) {}
+
+ /// copyValue - This method should be used whenever a preexisting value in the
+ /// program is copied or cloned, introducing a new value. Note that analysis
+ /// implementations should tolerate clients that use this method to introduce
+ /// the same value multiple times: if the analysis already knows about a
+ /// value, it should ignore the request.
+ ///
+ virtual void copyValue(Value *From, Value *To) {}
+
+ /// replaceWithNewValue - This method is the obvious combination of the two
+ /// above, and it provided as a helper to simplify client code.
+ ///
+ void replaceWithNewValue(Value *Old, Value *New) {
+ copyValue(Old, New);
+ deleteValue(Old);
+ }
};
+} // End llvm namespace
+
+// Force any file including this header to get the implementation as well
+FORCE_DEFINING_FILE_TO_BE_LINKED(BasicValueNumbering)
+
#endif