SPIRV-Tools/source/fuzz/fuzzer.cpp
Alastair Donaldson 1a89ac8b28
Transformation and fuzzer pass to add dead continues (#2758)
Similar to the existing 'add dead breaks' pass, this adds a pass to
add dead continues to blocks in loops where such a transformation is
viable.  Various functionality common to this new pass and 'add dead
breaks' has been factored into 'fuzzer_util', and some small
improvements to 'add dead breaks' that were identified while reviewing
that code again have been applied.

Fixes #2719.
2019-07-25 13:50:33 +01:00

136 lines
5.1 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.
#include "source/fuzz/fuzzer.h"
#include <cassert>
#include <sstream>
#include "source/fuzz/fact_manager.h"
#include "source/fuzz/fuzzer_context.h"
#include "source/fuzz/fuzzer_pass_add_dead_breaks.h"
#include "source/fuzz/fuzzer_pass_add_dead_continues.h"
#include "source/fuzz/fuzzer_pass_add_useful_constructs.h"
#include "source/fuzz/fuzzer_pass_obfuscate_constants.h"
#include "source/fuzz/fuzzer_pass_permute_blocks.h"
#include "source/fuzz/fuzzer_pass_split_blocks.h"
#include "source/fuzz/protobufs/spirvfuzz_protobufs.h"
#include "source/fuzz/pseudo_random_generator.h"
#include "source/opt/build_module.h"
#include "source/spirv_fuzzer_options.h"
#include "source/util/make_unique.h"
namespace spvtools {
namespace fuzz {
namespace {
const uint32_t kIdBoundGap = 100;
}
struct Fuzzer::Impl {
explicit Impl(spv_target_env env) : target_env(env) {}
const spv_target_env target_env; // Target environment.
MessageConsumer consumer; // Message consumer.
};
Fuzzer::Fuzzer(spv_target_env env) : impl_(MakeUnique<Impl>(env)) {}
Fuzzer::~Fuzzer() = default;
void Fuzzer::SetMessageConsumer(MessageConsumer c) {
impl_->consumer = std::move(c);
}
Fuzzer::FuzzerResultStatus Fuzzer::Run(
const std::vector<uint32_t>& binary_in,
const protobufs::FactSequence& initial_facts,
spv_const_fuzzer_options options, std::vector<uint32_t>* binary_out,
protobufs::TransformationSequence* transformation_sequence_out) const {
// Check compatibility between the library version being linked with and the
// header files being used.
GOOGLE_PROTOBUF_VERIFY_VERSION;
spvtools::SpirvTools tools(impl_->target_env);
tools.SetMessageConsumer(impl_->consumer);
if (!tools.IsValid()) {
impl_->consumer(SPV_MSG_ERROR, nullptr, {},
"Failed to create SPIRV-Tools interface; stopping.");
return Fuzzer::FuzzerResultStatus::kFailedToCreateSpirvToolsInterface;
}
// Initial binary should be valid.
if (!tools.Validate(&binary_in[0], binary_in.size())) {
impl_->consumer(SPV_MSG_ERROR, nullptr, {},
"Initial binary is invalid; stopping.");
return Fuzzer::FuzzerResultStatus::kInitialBinaryInvalid;
}
// Build the module from the input binary.
std::unique_ptr<opt::IRContext> ir_context = BuildModule(
impl_->target_env, impl_->consumer, binary_in.data(), binary_in.size());
assert(ir_context);
// Make a PRNG, either from a given seed or from a random device.
PseudoRandomGenerator random_generator(
options->has_random_seed ? options->random_seed
: static_cast<uint32_t>(std::random_device()()));
// The fuzzer will introduce new ids into the module. The module's id bound
// gives the smallest id that can be used for this purpose. We add an offset
// to this so that there is a sizeable gap between the ids used in the
// original module and the ids used for fuzzing, as a readability aid.
//
// TODO(https://github.com/KhronosGroup/SPIRV-Tools/issues/2541) consider the
// case where the maximum id bound is reached.
auto minimum_fresh_id = ir_context->module()->id_bound() + kIdBoundGap;
FuzzerContext fuzzer_context(&random_generator, minimum_fresh_id);
FactManager fact_manager;
fact_manager.AddFacts(impl_->consumer, initial_facts, ir_context.get());
// Add some essential ingredients to the module if they are not already
// present, such as boolean constants.
FuzzerPassAddUsefulConstructs(ir_context.get(), &fact_manager,
&fuzzer_context, transformation_sequence_out)
.Apply();
// Apply some semantics-preserving passes.
FuzzerPassSplitBlocks(ir_context.get(), &fact_manager, &fuzzer_context,
transformation_sequence_out)
.Apply();
FuzzerPassAddDeadBreaks(ir_context.get(), &fact_manager, &fuzzer_context,
transformation_sequence_out)
.Apply();
FuzzerPassAddDeadContinues(ir_context.get(), &fact_manager, &fuzzer_context,
transformation_sequence_out)
.Apply();
FuzzerPassObfuscateConstants(ir_context.get(), &fact_manager, &fuzzer_context,
transformation_sequence_out)
.Apply();
// Finally, give the blocks in the module a good shake-up.
FuzzerPassPermuteBlocks(ir_context.get(), &fact_manager, &fuzzer_context,
transformation_sequence_out)
.Apply();
// Encode the module as a binary.
ir_context->module()->ToBinary(binary_out, false);
return Fuzzer::FuzzerResultStatus::kComplete;
}
} // namespace fuzz
} // namespace spvtools