Turn mark deoptimize on undefined into a proper HPhase.

src/hydrogen-mark-deoptimize.h

Index: src/hydrogen-mark-deoptimize.h
diff --git a/src/hydrogen-mark-deoptimize.h b/src/hydrogen-mark-deoptimize.h
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+// Copyright 2013 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#ifndef V8_HYDROGEN_MARK_DEOPTIMIZE_H_
+#define V8_HYDROGEN_MARK_DEOPTIMIZE_H_
+
+#include "hydrogen.h"
+
+namespace v8 {
+namespace internal {
+
+
+// Compute DeoptimizeOnUndefined flag for phis.  Any phi that can reach a use
+// with DeoptimizeOnUndefined set must have DeoptimizeOnUndefined set.
+// Currently only HCompareNumericAndBranch, with double input representation,
+// has this flag set.  The flag is used by HChange tagged->double, which must
+// deoptimize if one of its uses has this flag set.
+class HMarkDeoptimizeOnUndefinedPhase : public HPhase {
+ public:
+  explicit HMarkDeoptimizeOnUndefinedPhase(HGraph* graph)
+      : HPhase("H_Mark deoptimize on undefined", graph),
+        worklist_(16, zone()) {}
+
+  void Run();
+
+ private:
+  void ProcessPhi(HPhi* phi);
+
+  // Preallocated worklist used as an optimization so we don't have
+  // to allocate a new ZoneList for every ProcessPhi() invocation.
+  ZoneList<HPhi*> worklist_;
+
+  DISALLOW_COPY_AND_ASSIGN(HMarkDeoptimizeOnUndefinedPhase);
+};
+
+
+} }  // namespace v8::internal
+
+#endif  // V8_HYDROGEN_MARK_DEOPTIMIZE_H_