SPIRV-Tools/source/reduce/reduction_pass.cpp
Alastair Donaldson f3acb955c2 Initial commit for spirv-reduce. (#2056)
Creates a new tool that can be used to reduce failing testcases, similar to creduce.
2018-11-21 14:03:09 -05:00

87 lines
2.6 KiB
C++

// Copyright (c) 2018 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 <algorithm>
#include "reduction_pass.h"
#include "source/opt/build_module.h"
namespace spvtools {
namespace reduce {
std::vector<uint32_t> ReductionPass::TryApplyReduction(
const std::vector<uint32_t>& binary) {
// We represent modules as binaries because (a) attempts at reduction need to
// end up in binary form to be passed on to SPIR-V-consuming tools, and (b)
// when we apply a reduction step we need to do it on a fresh version of the
// module as if the reduction step proves to be uninteresting we need to
// backtrack; re-parsing from binary provides a very clean way of cloning the
// module.
std::unique_ptr<opt::IRContext> context =
BuildModule(target_env_, consumer_, binary.data(), binary.size());
assert(context);
std::vector<std::unique_ptr<ReductionOpportunity>> opportunities =
GetAvailableOpportunities(context.get());
if (!is_initialized_) {
is_initialized_ = true;
index_ = 0;
granularity_ = (uint32_t)opportunities.size();
}
if (opportunities.empty()) {
granularity_ = 1;
return std::vector<uint32_t>();
}
assert(granularity_ > 0);
if (index_ >= opportunities.size()) {
index_ = 0;
granularity_ = std::max((uint32_t)1, granularity_ / 2);
return std::vector<uint32_t>();
}
for (uint32_t i = index_;
i < std::min(index_ + granularity_, (uint32_t)opportunities.size());
++i) {
opportunities[i]->TryToApply();
}
index_ += granularity_;
std::vector<uint32_t> result;
context->module()->ToBinary(&result, false);
return result;
}
void ReductionPass::SetMessageConsumer(MessageConsumer consumer) {
consumer_ = std::move(consumer);
}
bool ReductionPass::ReachedMinimumGranularity() const {
if (!is_initialized_) {
// Conceptually we can think that if the pass has not yet been initialized,
// it is operating at unbounded granularity.
return false;
}
assert(granularity_ != 0);
return granularity_ == 1;
}
} // namespace reduce
} // namespace spvtools