| buzbee | 311ca16 | 2013-02-28 15:56:43 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2013 The Android Open Source Project |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | #include "dataflow_iterator.h" |
| 18 | |
| 19 | namespace art { |
| 20 | |
| 21 | DataflowIterator::DataflowIterator(MIRGraph* mir_graph, DataFlowAnalysisMode dfa_mode, bool is_iterative) |
| 22 | : mir_graph_(mir_graph), |
| 23 | mode_(dfa_mode), |
| 24 | is_iterative_(is_iterative), |
| 25 | changed_(false) { |
| 26 | switch(mode_) { |
| 27 | case kAllNodes: |
| 28 | GrowableListIteratorInit(mir_graph_->GetBlockList(), &all_nodes_iterator_); |
| 29 | break; |
| 30 | |
| 31 | case kReachableNodes: |
| 32 | case kPreOrderDFSTraversal: |
| 33 | start_idx_ = 0; |
| 34 | end_idx_ = mir_graph_->GetNumReachableBlocks(); |
| 35 | idx_ = start_idx_; |
| 36 | block_id_list_ = mir_graph_->GetDfsOrder(); |
| 37 | reverse_ = false; |
| 38 | break; |
| 39 | |
| 40 | case kPostOrderDFSTraversal: |
| 41 | start_idx_ = mir_graph_->GetNumReachableBlocks() - 1; |
| 42 | end_idx_ = 0; |
| 43 | idx_ = start_idx_; |
| 44 | block_id_list_ = mir_graph_->GetDfsOrder(); |
| 45 | reverse_ = true; |
| 46 | break; |
| 47 | |
| 48 | case kPostOrderDOMTraversal: |
| 49 | start_idx_ = 0; |
| 50 | end_idx_ = mir_graph_->GetNumReachableBlocks(); |
| 51 | idx_ = start_idx_; |
| 52 | block_id_list_ = mir_graph_->GetDomPostOrder(); |
| 53 | reverse_ = false; |
| 54 | break; |
| 55 | |
| 56 | case kReversePostOrderTraversal: |
| 57 | start_idx_ = mir_graph_->GetNumReachableBlocks() - 1; |
| 58 | end_idx_ = 0; |
| 59 | idx_ = start_idx_; |
| 60 | block_id_list_ = mir_graph_->GetDfsPostOrder(); |
| 61 | reverse_ = true; |
| 62 | break; |
| 63 | default: |
| 64 | LOG(FATAL) << "Unknown traversal mode: " << dfa_mode; |
| 65 | } |
| 66 | } |
| 67 | |
| 68 | BasicBlock* DataflowIterator::NextBody(bool had_change) |
| 69 | { |
| 70 | changed_ |= had_change; |
| 71 | BasicBlock* res = NULL; |
| 72 | if (mode_ == kAllNodes) { |
| 73 | bool keep_looking = true; |
| 74 | while (keep_looking) { |
| 75 | res = reinterpret_cast<BasicBlock*>(GrowableListIteratorNext(&all_nodes_iterator_)); |
| 76 | if (is_iterative_ && changed_ && (res == NULL)) { |
| 77 | GrowableListIteratorInit(mir_graph_->GetBlockList(), &all_nodes_iterator_); |
| 78 | changed_ = false; |
| 79 | } else if ((res == NULL) || (!res->hidden)) { |
| 80 | keep_looking = false; |
| 81 | } |
| 82 | } |
| 83 | } else if (reverse_) { |
| 84 | if (is_iterative_ && changed_ && (idx_ < 0)) { |
| 85 | idx_ = start_idx_; |
| 86 | changed_ = false; |
| 87 | } |
| 88 | if (idx_ >= 0) { |
| 89 | int bb_id = block_id_list_->elem_list[idx_--]; |
| 90 | res = mir_graph_->GetBasicBlock(bb_id); |
| 91 | } |
| 92 | } else { |
| 93 | if (is_iterative_ && changed_ && (idx_ >= end_idx_)) { |
| 94 | idx_ = start_idx_; |
| 95 | changed_ = false; |
| 96 | } |
| 97 | if (idx_ < end_idx_) { |
| 98 | int bb_id = block_id_list_->elem_list[idx_++]; |
| 99 | res = mir_graph_->GetBasicBlock(bb_id); |
| 100 | } |
| 101 | } |
| 102 | return res; |
| 103 | } |
| 104 | |
| 105 | BasicBlock* DataflowIterator::Next(bool had_change) |
| 106 | { |
| 107 | DCHECK(is_iterative_); |
| 108 | return NextBody(had_change); |
| 109 | } |
| 110 | |
| 111 | BasicBlock* DataflowIterator::Next() |
| 112 | { |
| 113 | DCHECK(!is_iterative_); |
| 114 | return NextBody(false); |
| 115 | } |
| 116 | |
| 117 | } // namespace art |