Nested deoptimization environments.

runtime/vm/flow_graph_compiler.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"  // Needed here to get TARGET_ARCH_XXX.
 
 #include "vm/flow_graph_compiler.h"
 
 #include "vm/dart_entry.h"
 #include "vm/debugger.h"
@@ skipping 41 matching lines @@
   // area below FP, deoptimization environment does not track them.
   const intptr_t num_args =
       function.HasOptionalParameters() ? 0 : function.num_fixed_parameters();
   const intptr_t fixed_parameter_count =
       deoptimization_env_->fixed_parameter_count();
   DeoptInfoBuilder builder(compiler->object_table(), num_args);
 
   intptr_t slot_ix = 0;
   BuildReturnAddress(&builder, function, slot_ix++);
 
-  // All locals between TOS and PC-marker.
-  const GrowableArray<Value*>& values = deoptimization_env_->values();
-
   // Assign locations to values pushed above spill slots with PushArgument.
   intptr_t height = compiler->StackSize();
-  for (intptr_t i = 0; i < values.length(); i++) {
+  for (intptr_t i = 0; i < deoptimization_env_->Length(); i++) {

[Kevin Millikin (Google), 2012/09/07 12:51:52]

This also seems wrong.  There can be pushed arguments in outer environments. 
Consider:

f(e0, e1, g())

in the body of inlined function g, where f is not inlined.  The pushed values of
e0 and e1 will be found in an outer environment.

[zerny-google, 2012/09/07 13:51:37]

Yes. And this needs to be recursive (with a retn-addr before and the pc-marker
and fp after). Will change in the inline-deopt CL.

     if (deoptimization_env_->LocationAt(i).IsInvalid()) {
-      ASSERT(values[i]->definition()->IsPushArgument());
+      ASSERT(deoptimization_env_->ValueAt(i)->definition()->IsPushArgument());
       *deoptimization_env_->LocationSlotAt(i) = Location::StackSlot(height++);
     }
   }
 
-  for (intptr_t i = values.length() - 1; i >= fixed_parameter_count; i--) {
-    builder.AddCopy(deoptimization_env_->LocationAt(i), *values[i], slot_ix++);
+  for (intptr_t i = deoptimization_env_->Length() - 1;
+       i >= fixed_parameter_count;
+       i--) {
+    builder.AddCopy(deoptimization_env_->LocationAt(i),
+                    *deoptimization_env_->ValueAt(i),
+                    slot_ix++);
   }
 
   // PC marker, caller-fp, caller-pc.
   builder.AddPcMarker(function, slot_ix++);
   builder.AddCallerFp(slot_ix++);
   builder.AddCallerPc(slot_ix++);
   // Incoming arguments.
   for (intptr_t i = fixed_parameter_count - 1; i >= 0; i--) {
-    builder.AddCopy(deoptimization_env_->LocationAt(i), *values[i], slot_ix++);
+    builder.AddCopy(deoptimization_env_->LocationAt(i),
+                    *deoptimization_env_->ValueAt(i),
+                    slot_ix++);
   }
 
   const DeoptInfo& deopt_info = DeoptInfo::Handle(builder.CreateDeoptInfo());
   return deopt_info.raw();
 }
 
 
 FlowGraphCompiler::FlowGraphCompiler(Assembler* assembler,
                                      const FlowGraph& flow_graph,
                                      bool is_optimizing,
@@ skipping 748 matching lines @@
     case ABOVE:         return unsigned_left > unsigned_right;
     case ABOVE_EQUAL:   return unsigned_left >= unsigned_right;
     default:
       UNIMPLEMENTED();
       return false;
   }
 }
 
 
 }  // namespace dart