1//
2// Copyright (c) 2010 The ANGLE Project Authors. All rights reserved.
3// Use of this source code is governed by a BSD-style license that can be
4// found in the LICENSE file.
5//
6
7#include "GLSLANG/ShaderLang.h"
8#include "compiler/intermediate.h"
9
10class TInfoSinkBase;
11
12struct TLoopInfo {
13    struct TIndex {
14        int id;  // symbol id.
15    } index;
16    TIntermLoop* loop;
17};
18typedef TVector<TLoopInfo> TLoopStack;
19
20// Traverses intermediate tree to ensure that the shader does not exceed the
21// minimum functionality mandated in GLSL 1.0 spec, Appendix A.
22class ValidateLimitations : public TIntermTraverser {
23public:
24    ValidateLimitations(ShShaderType shaderType, TInfoSinkBase& sink);
25
26    int numErrors() const { return mNumErrors; }
27
28    virtual bool visitBinary(Visit, TIntermBinary*);
29    virtual bool visitUnary(Visit, TIntermUnary*);
30    virtual bool visitAggregate(Visit, TIntermAggregate*);
31    virtual bool visitLoop(Visit, TIntermLoop*);
32
33private:
34    void error(TSourceLoc loc, const char *reason, const char* token);
35
36    bool withinLoopBody() const;
37    bool isLoopIndex(const TIntermSymbol* symbol) const;
38    bool validateLoopType(TIntermLoop* node);
39    bool validateForLoopHeader(TIntermLoop* node, TLoopInfo* info);
40    bool validateForLoopInit(TIntermLoop* node, TLoopInfo* info);
41    bool validateForLoopCond(TIntermLoop* node, TLoopInfo* info);
42    bool validateForLoopExpr(TIntermLoop* node, TLoopInfo* info);
43    // Returns true if none of the loop indices is used as the argument to
44    // the given function out or inout parameter.
45    bool validateFunctionCall(TIntermAggregate* node);
46    bool validateOperation(TIntermOperator* node, TIntermNode* operand);
47
48    // Returns true if indexing does not exceed the minimum functionality
49    // mandated in GLSL 1.0 spec, Appendix A, Section 5.
50    bool isConstExpr(TIntermNode* node);
51    bool isConstIndexExpr(TIntermNode* node);
52    bool validateIndexing(TIntermBinary* node);
53
54    ShShaderType mShaderType;
55    TInfoSinkBase& mSink;
56    int mNumErrors;
57    TLoopStack mLoopStack;
58};
59
60