1    :  // Copyright 2013 Google Inc. All Rights Reserved.
   2    :  //
   3    :  // Licensed under the Apache License, Version 2.0 (the "License");
   4    :  // you may not use this file except in compliance with the License.
   5    :  // You may obtain a copy of the License at
   6    :  //
   7    :  //     http://www.apache.org/licenses/LICENSE-2.0
   8    :  //
   9    :  // Unless required by applicable law or agreed to in writing, software
  10    :  // distributed under the License is distributed on an "AS IS" BASIS,
  11    :  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12    :  // See the License for the specific language governing permissions and
  13    :  // limitations under the License.
  14    :  //
  15    :  // Implementation of ChainedBasicBlockTransform.
  16    :  
  17    :  #include "syzygy/block_graph/transforms/chained_basic_block_transforms.h"
  18    :  
  19    :  namespace block_graph {
  20    :  namespace transforms {
  21    :  
  22    :  const char ChainedBasicBlockTransforms::kTransformName[] =
  23    :      "ChainedBasicBlockTransforms";
  24    :  
  25    :  bool ChainedBasicBlockTransforms::AppendTransform(
  26  E :      BasicBlockSubGraphTransformInterface* transform) {
  27    :    DCHECK_NE(reinterpret_cast<BasicBlockSubGraphTransformInterface*>(NULL),
  28  E :              transform);
  29  E :    transforms_.push_back(transform);
  30  E :    return true;
  31  E :  }
  32    :  
  33    :  bool ChainedBasicBlockTransforms::OnBlock(
  34    :      const TransformPolicyInterface* policy,
  35    :      BlockGraph* block_graph,
  36  E :      BlockGraph::Block* block) {
  37  E :    DCHECK_NE(reinterpret_cast<TransformPolicyInterface*>(NULL), policy);
  38  E :    DCHECK_NE(reinterpret_cast<BlockGraph*>(NULL), block_graph);
  39  E :    DCHECK_NE(reinterpret_cast<BlockGraph::Block*>(NULL), block);
  40    :  
  41    :    // Avoid decomposition if no transforms are applied.
  42  E :    if (transforms_.empty())
  43  i :      return true;
  44    :  
  45    :    // Use the decomposition policy to skip blocks that aren't eligible for
  46    :    // basic-block decomposition.
  47  E :    if (!policy->BlockIsSafeToBasicBlockDecompose(block))
  48  E :      return true;
  49    :  
  50    :    // Apply the series of basic block transforms to this block.
  51    :    if (!ApplyBasicBlockSubGraphTransforms(
  52  E :             transforms_, policy, block_graph, block, NULL)) {
  53  i :      return false;
  54    :    }
  55    :  
  56  E :    return true;
  57  E :  }
  58    :  
  59    :  }  // namespace transforms
  60    :  }  // namespace block_graph