SPIRV-Tools/source/fuzz/fuzzer_pass.h
Alastair Donaldson 31acc78821
spirv-fuzz: Add fuzzer pass to perform module donation (#3117)
This change adds a fuzzer pass that allows code from other SPIR-V
modules to be donated into the module under transformation.  It also
changes the command-line options of the tools so that, in fuzzing
mode, a file must be specified that contains the names of available
donor modules.
2020-01-07 08:39:55 +00:00

113 lines
4.4 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 an instruction descriptor that allows the latest
// instruction to be located even if it has no result id.
//
// The code to manipulate the instruction descriptor 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
// |instruction_descriptor| parameter to the function object allows |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.
void MaybeAddTransformationBeforeEachInstruction(
std::function<
void(const opt::Function& function, opt::BasicBlock* block,
opt::BasicBlock::iterator inst_it,
const protobufs::InstructionDescriptor& instruction_descriptor)>
maybe_apply_transformation);
// A generic helper for applying a transforamtion that should be appplicable
// by construction, and adding it to the sequence of applied transformations.
template <typename TransformationType>
void ApplyTransformation(const TransformationType& transformation) {
assert(transformation.IsApplicable(GetIRContext(), *GetFactManager()) &&
"Transformation should be applicable by construction.");
transformation.Apply(GetIRContext(), GetFactManager());
*GetTransformations()->add_transformation() = transformation.ToMessage();
}
private:
opt::IRContext* ir_context_;
FactManager* fact_manager_;
FuzzerContext* fuzzer_context_;
protobufs::TransformationSequence* transformations_;
};
} // namespace fuzz
} // namespace spvtools
#endif // SOURCE_FUZZ_FUZZER_PASS_H_