Index: src/compiler/bytecode-branch-analysis.h |
diff --git a/src/compiler/bytecode-branch-analysis.h b/src/compiler/bytecode-branch-analysis.h |
new file mode 100644 |
index 0000000000000000000000000000000000000000..b035a752ff388f435b34e69b8bdf695b5614325b |
--- /dev/null |
+++ b/src/compiler/bytecode-branch-analysis.h |
@@ -0,0 +1,74 @@ |
+// Copyright 2015 the V8 project authors. All rights reserved. |
+// Use of this source code is governed by a BSD-style license that can be |
+// found in the LICENSE file. |
+ |
+#ifndef V8_COMPILER_BYTECODE_BRANCH_ANALYSIS_H_ |
+#define V8_COMPILER_BYTECODE_BRANCH_ANALYSIS_H_ |
+ |
+#include "src/bit-vector.h" |
+#include "src/compiler.h" |
+#include "src/zone-containers.h" |
+ |
+namespace v8 { |
+namespace internal { |
+namespace compiler { |
+ |
+class BytecodeBranchInfo; |
+ |
+class BytecodeBranchAnalysis BASE_EMBEDDED { |
rmcilroy
2015/12/15 17:35:43
A comment on what the class does would be good
oth
2015/12/15 22:42:17
Done.
|
+ public: |
+ BytecodeBranchAnalysis(Handle<BytecodeArray> bytecode_array, Zone* zone) |
+ : branch_infos_(zone), |
+ bytecode_array_(bytecode_array), |
+ reachable_(bytecode_array->length(), zone), |
+ zone_(zone) {} |
+ |
+ void Analyze(); |
rmcilroy
2015/12/15 17:35:43
Comment?
oth
2015/12/15 22:42:17
Done.
|
+ |
+ // Offsets of bytecodes having a backward branch to the bytecode at |offset|. |
+ const ZoneVector<int>* BackwardBranchesTargetting(int offset) const; |
+ |
+ // Offsets of bytecodes having a foreward branch to the bytecode at |offset|. |
rmcilroy
2015/12/15 17:35:43
/s/foreward/forward
oth
2015/12/15 22:42:17
Done.
|
+ const ZoneVector<int>* ForwardBranchesTargetting(int offset) const; |
+ |
+ // Returns true if the bytecode at |offset| is reachable. |
+ bool is_reachable(int offset) const { return reachable_.Contains(offset); } |
+ |
+ // Returns true if there are any forward branches to the bytecode at |
+ // |offset|. |
+ bool forward_branches_target(int offset) const { |
+ const ZoneVector<int>* sites = ForwardBranchesTargetting(offset); |
+ return sites != nullptr && sites->size() > 0; |
+ } |
+ |
+ // Returns true if there are any backward branches to the bytecode |
+ // at |offset|. |
+ bool backward_branches_target(int offset) const { |
+ const ZoneVector<int>* sites = BackwardBranchesTargetting(offset); |
+ return sites != nullptr && sites->size() > 0; |
+ } |
+ |
+ // Returns true if the bytecode at |offset| is the last backwards branch to |
+ // |branch_target|. |
+ bool IsLastBackwardBranchTo(int branch_target, int offset) const; |
+ |
+ private: |
+ void AddBranch(int origin_offset, int target_offset); |
+ |
+ Zone* zone() const { return zone_; } |
+ Handle<BytecodeArray> bytecode_array() const { return bytecode_array_; } |
+ |
+ ZoneMap<int, BytecodeBranchInfo*> branch_infos_; |
+ Handle<BytecodeArray> bytecode_array_; |
+ BitVector reachable_; |
+ Zone* zone_; |
+ |
+ DISALLOW_COPY_AND_ASSIGN(BytecodeBranchAnalysis); |
+}; |
+ |
+ |
+} // namespace compiler |
+} // namespace internal |
+} // namespace v8 |
+ |
+#endif // V8_COMPILER_BYTECODE_BRANCH_ANALYSIS_H_ |