Record the lazy deoptimization environmnent only at LLazyBailout-instructions...

src/ia32/lithium-ia32.cc

Index: src/ia32/lithium-ia32.cc
===================================================================
--- src/ia32/lithium-ia32.cc	(revision 6436)
+++ src/ia32/lithium-ia32.cc	(working copy)
@@ -656,22 +656,6 @@
 }
 
 
-LInstruction* LChunkBuilder::SetInstructionPendingDeoptimizationEnvironment(
-    LInstruction* instr, int ast_id) {
-  ASSERT(instructions_pending_deoptimization_environment_ == NULL);
-  ASSERT(pending_deoptimization_ast_id_ == AstNode::kNoNumber);
-  instructions_pending_deoptimization_environment_ = instr;
-  pending_deoptimization_ast_id_ = ast_id;
-  return instr;
-}
-
-
-void LChunkBuilder::ClearInstructionPendingDeoptimizationEnvironment() {
-  instructions_pending_deoptimization_environment_ = NULL;
-  pending_deoptimization_ast_id_ = AstNode::kNoNumber;
-}
-
-
 LInstruction* LChunkBuilder::MarkAsCall(LInstruction* instr,
                                         HInstruction* hinstr,
                                         CanDeoptimize can_deoptimize) {
@@ -681,8 +665,8 @@
   if (hinstr->HasSideEffects()) {
     ASSERT(hinstr->next()->IsSimulate());
     HSimulate* sim = HSimulate::cast(hinstr->next());
-    instr = SetInstructionPendingDeoptimizationEnvironment(
-        instr, sim->ast_id());
+    ASSERT(pending_deoptimization_ast_id_ == AstNode::kNoNumber);
+    pending_deoptimization_ast_id_ = sim->ast_id();
   }
 
   // If instruction does not have side-effects lazy deoptimization
@@ -1877,9 +1861,7 @@
   if (pending_deoptimization_ast_id_ == instr->ast_id()) {

[Kevin Millikin (Chromium), 2011/01/24 13:31:38]

This should really be:

if (pending_deoptimization_ast_id_ != AstNode::kNoNumber) {
  ASSERT(pending_deoptimization_ast_id_ == instr->ast_id());
  ...

     LLazyBailout* lazy_bailout = new LLazyBailout;
     LInstruction* result = AssignEnvironment(lazy_bailout);

[Kevin Millikin (Chromium), 2011/01/24 13:31:38]

I'm worried that the uses in this environment appear to come after the gap the
precedes it, but the environment before the gap is the one that is recorded.

Is that a problem?

-    instructions_pending_deoptimization_environment_->
-        set_deoptimization_environment(result->environment());
-    ClearInstructionPendingDeoptimizationEnvironment();
+    pending_deoptimization_ast_id_ = AstNode::kNoNumber;
     return result;
   }