1 // Copyright (c) 2021 Mostafa Ashraf
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 #include "source/fuzz/fuzzer_pass_permute_function_variables.h"
16
17 #include <algorithm>
18 #include <numeric>
19 #include <vector>
20
21 #include "source/fuzz/fuzzer_context.h"
22 #include "source/fuzz/fuzzer_util.h"
23 #include "source/fuzz/instruction_descriptor.h"
24 #include "source/fuzz/transformation_swap_function_variables.h"
25
26 namespace spvtools {
27 namespace fuzz {
28
FuzzerPassPermuteFunctionVariables(opt::IRContext * ir_context,TransformationContext * transformation_context,FuzzerContext * fuzzer_context,protobufs::TransformationSequence * transformations,bool ignore_inapplicable_transformations)29 FuzzerPassPermuteFunctionVariables::FuzzerPassPermuteFunctionVariables(
30 opt::IRContext* ir_context, TransformationContext* transformation_context,
31 FuzzerContext* fuzzer_context,
32 protobufs::TransformationSequence* transformations,
33 bool ignore_inapplicable_transformations)
34 : FuzzerPass(ir_context, transformation_context, fuzzer_context,
35 transformations, ignore_inapplicable_transformations) {
36 } // Here we call parent constructor.
37
Apply()38 void FuzzerPassPermuteFunctionVariables::Apply() {
39 // Permuting OpVariable instructions in each function.
40 for (auto& function : *GetIRContext()->module()) {
41 if (!GetFuzzerContext()->ChoosePercentage(
42 GetFuzzerContext()->GetChanceOfPermutingFunctionVariables())) {
43 continue;
44 }
45
46 auto first_block = function.entry().get();
47
48 std::vector<opt::Instruction*> variables;
49 for (auto& instruction : *first_block) {
50 if (instruction.opcode() == SpvOpVariable) {
51 variables.push_back(&instruction);
52 }
53 }
54 if (variables.size() <= 1) {
55 continue;
56 }
57 do {
58 uint32_t instruction_1_index = GetFuzzerContext()->RandomIndex(variables);
59 uint32_t instruction_2_index = GetFuzzerContext()->RandomIndex(variables);
60
61 if (instruction_1_index != instruction_2_index) {
62 ApplyTransformation(TransformationSwapFunctionVariables(
63 variables[instruction_1_index]->result_id(),
64 variables[instruction_2_index]->result_id()));
65 }
66
67 } while (GetFuzzerContext()->ChoosePercentage(
68 GetFuzzerContext()
69 ->GetChanceOfSwappingAnotherPairOfFunctionVariables()) &&
70 variables.size() > 2);
71 }
72 }
73
74 } // namespace fuzz
75 } // namespace spvtools
76