1 //===-- DiffConsumer.h - Difference Consumer --------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This header defines the interface to the LLVM difference Consumer
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef LLVM_TOOLS_LLVM_DIFF_DIFFCONSUMER_H
14 #define LLVM_TOOLS_LLVM_DIFF_DIFFCONSUMER_H
15 
16 #include "DiffLog.h"
17 #include "llvm/ADT/DenseMap.h"
18 #include "llvm/ADT/SmallVector.h"
19 #include "llvm/IR/Value.h"
20 #include "llvm/Support/Casting.h"
21 #include "llvm/Support/raw_ostream.h"
22 
23 namespace llvm {
24 class StringRef;
25   class Module;
26   class Value;
27   class Function;
28 
29   /// The interface for consumers of difference data.
30   class Consumer {
31     virtual void anchor();
32   public:
33     /// Record that a local context has been entered.  Left and
34     /// Right are IR "containers" of some sort which are being
35     /// considered for structural equivalence: global variables,
36     /// functions, blocks, instructions, etc.
37     virtual void enterContext(const Value *Left, const Value *Right) = 0;
38 
39     /// Record that a local context has been exited.
40     virtual void exitContext() = 0;
41 
42     /// Record a difference within the current context.
43     virtual void log(StringRef Text) = 0;
44 
45     /// Record a formatted difference within the current context.
46     virtual void logf(const LogBuilder &Log) = 0;
47 
48     /// Record a line-by-line instruction diff.
49     virtual void logd(const DiffLogBuilder &Log) = 0;
50 
51   protected:
52     virtual ~Consumer() {}
53   };
54 
55   class DiffConsumer : public Consumer {
56   private:
57     struct DiffContext {
58       DiffContext(const Value *L, const Value *R)
59           : L(L), R(R), Differences(false), IsFunction(isa<Function>(L)) {}
60       const Value *L;
61       const Value *R;
62       bool Differences;
63       bool IsFunction;
64       DenseMap<const Value *, unsigned> LNumbering;
65       DenseMap<const Value *, unsigned> RNumbering;
66     };
67 
68     raw_ostream &out;
69     SmallVector<DiffContext, 5> contexts;
70     bool Differences;
71     unsigned Indent;
72 
73     void printValue(const Value *V, bool isL);
74     void header();
75     void indent();
76 
77   public:
78     DiffConsumer()
79       : out(errs()), Differences(false), Indent(0) {}
80 
81     void reset();
82     bool hadDifferences() const;
83     void enterContext(const Value *L, const Value *R) override;
84     void exitContext() override;
85     void log(StringRef text) override;
86     void logf(const LogBuilder &Log) override;
87     void logd(const DiffLogBuilder &Log) override;
88   };
89 }
90 
91 #endif
92