1 // Copyright (c) 2019 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 #include "source/fuzz/fuzzer_pass_adjust_function_controls.h"
16
17 #include "source/fuzz/transformation_set_function_control.h"
18
19 namespace spvtools {
20 namespace fuzz {
21
FuzzerPassAdjustFunctionControls( opt::IRContext* ir_context, TransformationContext* transformation_context, FuzzerContext* fuzzer_context, protobufs::TransformationSequence* transformations, bool ignore_inapplicable_transformations)22 FuzzerPassAdjustFunctionControls::FuzzerPassAdjustFunctionControls(
23 opt::IRContext* ir_context, TransformationContext* transformation_context,
24 FuzzerContext* fuzzer_context,
25 protobufs::TransformationSequence* transformations,
26 bool ignore_inapplicable_transformations)
27 : FuzzerPass(ir_context, transformation_context, fuzzer_context,
28 transformations, ignore_inapplicable_transformations) {}
29
Apply()30 void FuzzerPassAdjustFunctionControls::Apply() {
31 // Consider every function in the module.
32 for (auto& function : *GetIRContext()->module()) {
33 // Randomly decide whether to adjust this function's controls.
34 if (GetFuzzerContext()->ChoosePercentage(
35 GetFuzzerContext()->GetChanceOfAdjustingFunctionControl())) {
36 // Grab the function control mask for the function in its present form.
37 uint32_t existing_function_control_mask =
38 function.DefInst().GetSingleWordInOperand(0);
39
40 // For the new mask, we first randomly select one of three basic masks:
41 // None, Inline or DontInline. These are always valid (and are mutually
42 // exclusive).
43 std::vector<spv::FunctionControlMask> basic_function_control_masks = {
44 spv::FunctionControlMask::MaskNone, spv::FunctionControlMask::Inline,
45 spv::FunctionControlMask::DontInline};
46 uint32_t new_function_control_mask =
47 uint32_t(basic_function_control_masks[GetFuzzerContext()->RandomIndex(
48 basic_function_control_masks)]);
49
50 // We now consider the Pure and Const mask bits. If these are already
51 // set on the function then it's OK to keep them, but also interesting
52 // to consider dropping them, so we decide randomly in each case.
53 for (auto mask_bit :
54 {spv::FunctionControlMask::Pure, spv::FunctionControlMask::Const}) {
55 if ((existing_function_control_mask & uint32_t(mask_bit)) &&
56 GetFuzzerContext()->ChooseEven()) {
57 new_function_control_mask |= uint32_t(mask_bit);
58 }
59 }
60
61 // Create and add a transformation.
62 TransformationSetFunctionControl transformation(
63 function.DefInst().result_id(), new_function_control_mask);
64 ApplyTransformation(transformation);
65 }
66 }
67 }
68
69 } // namespace fuzz
70 } // namespace spvtools
71