SPIRV-Tools/source/fuzz/fuzzer_pass.h
Alastair Donaldson 5910bb8e94
spirv-fuzz: add transformation and pass to construct composites (#2941)
Adds a fuzzer pass and transformation to create a composite (array,
matrix, struct or vector) from available constituent components, and
inform the fact manager that each component of the new composite is
synonymous with the id that was used to construct it. This allows the
"replace id with synonym" pass to then replace uses of said ids with
uses of elements extracted from the composite.

Fixes #2858.
2019-10-08 14:04:10 +01:00

104 lines
3.9 KiB
C++

// Copyright (c) 2019 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef SOURCE_FUZZ_FUZZER_PASS_H_
#define SOURCE_FUZZ_FUZZER_PASS_H_
#include <functional>
#include <vector>
#include "source/fuzz/fact_manager.h"
#include "source/fuzz/fuzzer_context.h"
#include "source/fuzz/protobufs/spirvfuzz_protobufs.h"
#include "source/opt/ir_context.h"
namespace spvtools {
namespace fuzz {
// Interface for applying a pass of transformations to a module.
class FuzzerPass {
public:
FuzzerPass(opt::IRContext* ir_context, FactManager* fact_manager,
FuzzerContext* fuzzer_context,
protobufs::TransformationSequence* transformations);
virtual ~FuzzerPass();
// Applies the pass to the module |ir_context_|, assuming and updating
// facts from |fact_manager_|, and using |fuzzer_context_| to guide the
// process. Appends to |transformations_| all transformations that were
// applied during the pass.
virtual void Apply() = 0;
protected:
opt::IRContext* GetIRContext() const { return ir_context_; }
FactManager* GetFactManager() const { return fact_manager_; }
FuzzerContext* GetFuzzerContext() const { return fuzzer_context_; }
protobufs::TransformationSequence* GetTransformations() const {
return transformations_;
}
// Returns all instructions that are *available* at |inst_it|, which is
// required to be inside block |block| of function |function| - that is, all
// instructions at global scope and all instructions that strictly dominate
// |inst_it|.
//
// Filters said instructions to return only those that satisfy the
// |instruction_is_relevant| predicate. This, for instance, could ignore all
// instructions that have a particular decoration.
std::vector<opt::Instruction*> FindAvailableInstructions(
const opt::Function& function, opt::BasicBlock* block,
opt::BasicBlock::iterator inst_it,
std::function<bool(opt::IRContext*, opt::Instruction*)>
instruction_is_relevant);
// A helper method that iterates through each instruction in each block, at
// all times tracking a base instruction and offset that allows that latest
// instruction to be located even if it has no result id.
//
// The code to manipulate the base and offset is a bit fiddly, and the point
// of this method is to avoiding having to duplicate it in multiple
// transformation passes.
//
// The function |maybe_apply_transformation| is invoked for each instruction
// |inst_it| in block |block| of function |function| that is encountered. The
// |base| and |offset| parameters to the function object allow |inst_it| to be
// identified.
//
// The job of |maybe_apply_transformation| is to randomly decide whether to
// try to apply some transformation, and then - if selected - to attempt to
// apply it. The function returns the number of instructions that were
// inserted before |inst_it|, so that |offset| can be updated.
//
void MaybeAddTransformationBeforeEachInstruction(
std::function<uint32_t(
const opt::Function& function, opt::BasicBlock* block,
opt::BasicBlock::iterator inst_it, uint32_t base, uint32_t offset)>
maybe_apply_transformation);
private:
opt::IRContext* ir_context_;
FactManager* fact_manager_;
FuzzerContext* fuzzer_context_;
protobufs::TransformationSequence* transformations_;
};
} // namespace fuzz
} // namespace spvtools
#endif // SOURCE_FUZZ_FUZZER_PASS_H_