1 //===-- DifferenceEngine.h - Module comparator ------------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This header defines the interface to the LLVM difference engine,
11 // which structurally compares functions within a module.
13 //===----------------------------------------------------------------------===//
15 #ifndef _LLVM_DIFFERENCE_ENGINE_H_
16 #define _LLVM_DIFFERENCE_ENGINE_H_
18 #include "DiffConsumer.h"
20 #include "llvm/ADT/SmallVector.h"
21 #include "llvm/ADT/StringRef.h"
33 /// A class for performing structural comparisons of LLVM assembly.
34 class DifferenceEngine {
36 /// A RAII object for recording the current context.
38 Context(DifferenceEngine &Engine, Value *L, Value *R) : Engine(Engine) {
39 Engine.consumer.enterContext(L, R);
43 Engine.consumer.exitContext();
47 DifferenceEngine &Engine;
50 /// An oracle for answering whether two values are equivalent as
53 virtual void anchor();
55 virtual bool operator()(Value *L, Value *R) = 0;
61 DifferenceEngine(Consumer &consumer)
62 : consumer(consumer), globalValueOracle(0) {}
64 void diff(Module *L, Module *R);
65 void diff(Function *L, Function *R);
66 void log(StringRef text) {
69 LogBuilder logf(StringRef text) {
70 return LogBuilder(consumer, text);
72 Consumer& getConsumer() const { return consumer; }
74 /// Installs an oracle to decide whether two global values are
75 /// equivalent as operands. Without an oracle, global values are
76 /// considered equivalent as operands precisely when they have the
78 void setGlobalValueOracle(Oracle *oracle) {
79 globalValueOracle = oracle;
82 /// Determines whether two global values are equivalent.
83 bool equivalentAsOperands(GlobalValue *L, GlobalValue *R);
87 Oracle *globalValueOracle;