llvm-6502/include/llvm/Analysis/ValueNumbering.h
Devang Patel 3e15bf33e0 Use 'static const char' instead of 'static const int'.
Due to darwin gcc bug, one version of darwin linker coalesces
static const int, which defauts PassID based pass identification.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36652 91177308-0d34-0410-b5e6-96231b3b80d8
2007-05-02 21:39:20 +00:00

75 lines
2.7 KiB
C++

//===- 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
// common interface used by all clients of value numbering information, and
// implemented by all value numbering implementations.
//
// Implementations of this interface must implement the various virtual methods,
// which automatically provides functionality for the entire suite of client
// APIs.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_ANALYSIS_VALUE_NUMBERING_H
#define LLVM_ANALYSIS_VALUE_NUMBERING_H
#include <vector>
#include "llvm/Pass.h"
namespace llvm {
class Value;
class Instruction;
struct ValueNumbering {
static const char ID; // Class identification, replacement for typeinfo
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;
///===-------------------------------------------------------------------===//
/// 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