First implementation of allocation elimination in Hydrogen.

src/hydrogen.cc

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@@ skipping 2943 matching lines @@
         "Unsupported phi use of const variable"));
     return false;
   }
   Run<HRedundantPhiEliminationPhase>();
   if (!CheckArgumentsPhiUses()) {
     *bailout_reason = SmartArrayPointer<char>(StrDup(
         "Unsupported phi use of arguments"));
     return false;
   }
 
+  if (FLAG_use_escape_analysis) Run<HEscapeAnalysisPhase>();

[titzer, 2013/08/06 12:15:47]

I think you might want to run after the first DCE phase, so that objects don't
escape through dead code somehow.

[Michael Starzinger, 2013/08/07 10:51:16]

Done. Moved to after DCE.

+
   // Remove dead code and phis
   if (FLAG_dead_code_elimination) Run<HDeadCodeEliminationPhase>();
   CollectPhis();
 
   if (has_osr()) osr()->FinishOsrValues();
 
   Run<HInferRepresentationPhase>();
 
   // Remove HSimulate instructions that have turned out not to be needed
   // after all by folding them into the following HSimulate.
   // This must happen after inferring representations.
   Run<HMergeRemovableSimulatesPhase>();
 
   Run<HMarkDeoptimizeOnUndefinedPhase>();
   Run<HRepresentationChangesPhase>();
 
   Run<HInferTypesPhase>();
 
   // Must be performed before canonicalization to ensure that Canonicalize
   // will not remove semantically meaningful ToInt32 operations e.g. BIT_OR with
   // zero.
   if (FLAG_opt_safe_uint32_operations) Run<HUint32AnalysisPhase>();
 
   if (FLAG_use_canonicalizing) Run<HCanonicalizePhase>();
 
-  if (FLAG_use_escape_analysis) Run<HEscapeAnalysisPhase>();
-
   if (FLAG_use_gvn) Run<HGlobalValueNumberingPhase>();
 
   if (FLAG_use_range) Run<HRangeAnalysisPhase>();
 
   Run<HComputeMinusZeroChecksPhase>();
 
   // Eliminate redundant stack checks on backwards branches.
   Run<HStackCheckEliminationPhase>();
 
   if (FLAG_idefs) SetupInformativeDefinitions();
@@ skipping 6886 matching lines @@
   if (ShouldProduceTraceOutput()) {
     isolate()->GetHTracer()->TraceHydrogen(name(), graph_);
   }
 
 #ifdef DEBUG
   graph_->Verify(false);  // No full verify.
 #endif
 }
 
 } }  // namespace v8::internal