mirror of
https://github.com/KhronosGroup/SPIRV-Tools
synced 2024-12-02 23:50:13 +00:00
b8587c984a
This change allows the reducer to merge together blocks even when they are unreachable, but keeps the restriction of reachability in place for the optimizer. Fixes #4302.
90 lines
3.1 KiB
C++
90 lines
3.1 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/transformation_merge_blocks.h"
|
|
|
|
#include "source/fuzz/fuzzer_util.h"
|
|
#include "source/opt/block_merge_util.h"
|
|
|
|
namespace spvtools {
|
|
namespace fuzz {
|
|
|
|
TransformationMergeBlocks::TransformationMergeBlocks(
|
|
protobufs::TransformationMergeBlocks message)
|
|
: message_(std::move(message)) {}
|
|
|
|
TransformationMergeBlocks::TransformationMergeBlocks(uint32_t block_id) {
|
|
message_.set_block_id(block_id);
|
|
}
|
|
|
|
bool TransformationMergeBlocks::IsApplicable(
|
|
opt::IRContext* ir_context, const TransformationContext& /*unused*/) const {
|
|
auto second_block =
|
|
fuzzerutil::MaybeFindBlock(ir_context, message_.block_id());
|
|
// The given block must exist.
|
|
if (!second_block) {
|
|
return false;
|
|
}
|
|
// The block must have just one predecessor.
|
|
auto predecessors = ir_context->cfg()->preds(second_block->id());
|
|
if (predecessors.size() != 1) {
|
|
return false;
|
|
}
|
|
auto first_block = ir_context->cfg()->block(predecessors.at(0));
|
|
|
|
if (!ir_context->IsReachable(*first_block)) {
|
|
return false;
|
|
}
|
|
return opt::blockmergeutil::CanMergeWithSuccessor(ir_context, first_block);
|
|
}
|
|
|
|
void TransformationMergeBlocks::Apply(opt::IRContext* ir_context,
|
|
TransformationContext* /*unused*/) const {
|
|
auto second_block =
|
|
fuzzerutil::MaybeFindBlock(ir_context, message_.block_id());
|
|
auto first_block = ir_context->cfg()->block(
|
|
ir_context->cfg()->preds(second_block->id()).at(0));
|
|
|
|
auto function = first_block->GetParent();
|
|
// We need an iterator pointing to the predecessor, hence the loop.
|
|
for (auto bi = function->begin(); bi != function->end(); ++bi) {
|
|
if (bi->id() == first_block->id()) {
|
|
assert(opt::blockmergeutil::CanMergeWithSuccessor(ir_context, &*bi) &&
|
|
"Because 'Apply' should only be invoked if 'IsApplicable' holds, "
|
|
"it must be possible to merge |bi| with its successor.");
|
|
opt::blockmergeutil::MergeWithSuccessor(ir_context, function, bi);
|
|
// Invalidate all analyses, since we have changed the module
|
|
// significantly.
|
|
ir_context->InvalidateAnalysesExceptFor(opt::IRContext::kAnalysisNone);
|
|
return;
|
|
}
|
|
}
|
|
assert(false &&
|
|
"Control should not reach here - we should always find the desired "
|
|
"block");
|
|
}
|
|
|
|
protobufs::Transformation TransformationMergeBlocks::ToMessage() const {
|
|
protobufs::Transformation result;
|
|
*result.mutable_merge_blocks() = message_;
|
|
return result;
|
|
}
|
|
|
|
std::unordered_set<uint32_t> TransformationMergeBlocks::GetFreshIds() const {
|
|
return std::unordered_set<uint32_t>();
|
|
}
|
|
|
|
} // namespace fuzz
|
|
} // namespace spvtools
|