Synchronize with r15701.

src/hydrogen-canonicalize.cc

Index: src/hydrogen-canonicalize.cc
diff --git a/src/hydrogen-escape-analysis.cc b/src/hydrogen-canonicalize.cc
similarity index 62%
copy from src/hydrogen-escape-analysis.cc
copy to src/hydrogen-canonicalize.cc
index e852fb8d6d75d7756df6e4e03399bfb8789d4c76..40cbe4c0655d4cd315d761fbf0d63b3aa0530a95 100644
--- a/src/hydrogen-escape-analysis.cc
+++ b/src/hydrogen-canonicalize.cc
@@ -25,42 +25,35 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-#include "hydrogen-escape-analysis.h"
+#include "hydrogen-canonicalize.h"
 
 namespace v8 {
 namespace internal {
 
-
-void HEscapeAnalysisPhase::CollectIfNoEscapingUses(HInstruction* instr) {
-  for (HUseIterator it(instr->uses()); !it.Done(); it.Advance()) {
-    HValue* use = it.value();
-    if (use->HasEscapingOperandAt(it.index())) {
-      if (FLAG_trace_escape_analysis) {
-        PrintF("#%d (%s) escapes through #%d (%s) @%d\n", instr->id(),
-               instr->Mnemonic(), use->id(), use->Mnemonic(), it.index());
+void HCanonicalizePhase::Run() {
+  const ZoneList<HBasicBlock*>* blocks(graph()->blocks());
+  // Before removing no-op instructions, save their semantic value.
+  // We must be careful not to set the flag unnecessarily, because GVN
+  // cannot identify two instructions when their flag value differs.
+  for (int i = 0; i < blocks->length(); ++i) {
+    for (HInstructionIterator it(blocks->at(i)); !it.Done(); it.Advance()) {
+      HInstruction* instr = it.Current();
+      if (instr->IsArithmeticBinaryOperation() &&
+          instr->representation().IsInteger32() &&
+          instr->HasAtLeastOneUseWithFlagAndNoneWithout(
+              HInstruction::kTruncatingToInt32)) {
+        instr->SetFlag(HInstruction::kAllUsesTruncatingToInt32);
       }
-      return;
     }
   }
-  if (FLAG_trace_escape_analysis) {
-    PrintF("#%d (%s) is being captured\n", instr->id(), instr->Mnemonic());
-  }
-  captured_.Add(instr, zone());
-}
-
-
-void HEscapeAnalysisPhase::CollectCapturedValues() {
-  int block_count = graph()->blocks()->length();
-  for (int i = 0; i < block_count; ++i) {
-    HBasicBlock* block = graph()->blocks()->at(i);
-    for (HInstructionIterator it(block); !it.Done(); it.Advance()) {
+  // Perform actual Canonicalization pass.
+  for (int i = 0; i < blocks->length(); ++i) {
+    for (HInstructionIterator it(blocks->at(i)); !it.Done(); it.Advance()) {
       HInstruction* instr = it.Current();
-      if (instr->IsAllocate() || instr->IsAllocateObject()) {
-        CollectIfNoEscapingUses(instr);
-      }
+      HValue* value = instr->Canonicalize();
+      if (value != instr) instr->DeleteAndReplaceWith(value);
     }
   }
 }
 
-
 } }  // namespace v8::internal