1// Copyright (c) 2018 Google LLC
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7// http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15#ifndef SOURCE_OPT_REPLACE_INVALID_OPC_H_
16#define SOURCE_OPT_REPLACE_INVALID_OPC_H_
17
18#include <string>
19
20#include "source/opt/pass.h"
21
22namespace spvtools {
23namespace opt {
24
25// This pass will runs on shader modules only. It will replace the result of
26// instructions that are valid for shader modules, but not the current shader
27// stage, with a constant value. If the instruction does not have a return
28// value, the instruction will simply be deleted.
29class ReplaceInvalidOpcodePass : public Pass {
30 public:
31 const char* name() const override { return "replace-invalid-opcode"; }
32 Status Process() override;
33
34 private:
35 // Returns the execution model that is used by every entry point in the
36 // module. If more than one execution model is used in the module, then the
37 // return value is SpvExecutionModelMax.
38 SpvExecutionModel GetExecutionModel();
39
40 // Replaces all instructions in |function| that are invalid with execution
41 // model |mode|, but valid for another shader model, with a special constant
42 // value. See |GetSpecialConstant|.
43 bool RewriteFunction(Function* function, SpvExecutionModel mode);
44
45 // Returns true if |inst| is valid for fragment shaders only.
46 bool IsFragmentShaderOnlyInstruction(Instruction* inst);
47
48 // Replaces all uses of the result of |inst|, if there is one, with the id of
49 // a special constant. Then |inst| is killed. |inst| cannot be a block
50 // terminator because the basic block will then become invalid. |inst| is no
51 // longer valid after calling this function.
52 void ReplaceInstruction(Instruction* inst, const char* source,
53 uint32_t line_number, uint32_t column_number);
54
55 // Returns the id of a constant with type |type_id|. The type must be an
56 // integer, float, or vector. For scalar types, the hex representation of the
57 // constant will be the concatenation of 0xDEADBEEF with itself until the
58 // width of the type has been reached. For a vector, each element of the
59 // constant will be constructed the same way.
60 uint32_t GetSpecialConstant(uint32_t type_id);
61 std::string BuildWarningMessage(SpvOp opcode);
62};
63
64} // namespace opt
65} // namespace spvtools
66
67#endif // SOURCE_OPT_REPLACE_INVALID_OPC_H_
68