Finish implementing lazy deoptimization (ia32, x64). Ran tests with --deoptimize-alot.

runtime/vm/code_generator.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/code_generator.h"
 
 #include "vm/assembler_macros.h"
 #include "vm/ast.h"
 #include "vm/code_patcher.h"
 #include "vm/compiler.h"
@@ skipping 1434 matching lines @@
       intptr_t deopt_id, deopt_reason, deopt_index;
       GetDeoptIxDescrAtPc(optimized_code, frame->pc(),
                           &deopt_id, &deopt_reason, &deopt_index);
       ASSERT(deopt_id != Isolate::kNoDeoptId);
       function = optimized_code.function();
       unoptimized_code = function.unoptimized_code();
       ASSERT(!unoptimized_code.IsNull());
       uword continue_at_pc =
           unoptimized_code.GetDeoptAfterPcAtDeoptId(deopt_id);
       ASSERT(continue_at_pc != 0);
+      // The switch to unoptimized code may have already occured.
+      if (function.HasOptimizedCode()) {
+        function.SwitchToUnoptimizedCode();
+      }
+      // Patch call site (lazy deoptimization is quite rare, patching it twice
+      // is not a performance issue).
+      uword lazy_deopt_jump = optimized_code.GetLazyDeoptPc();
+      ASSERT(lazy_deopt_jump != 0);
+      CodePatcher::InsertCallAt(frame->pc(), lazy_deopt_jump);
+      // Mark code as dead (do not GC its embedded objects).
+      optimized_code.set_is_alive(false);
     }
     frame = iterator.NextFrame();
   }
 }
 
 
 // Copy saved registers into the isolate buffer.
 static void CopySavedRegisters(uword saved_registers_address) {
   double* xmm_registers_copy = new double[kNumberOfXmmRegisters];
   ASSERT(xmm_registers_copy != NULL);
@@ skipping 156 matching lines @@
   ASSERT(!unoptimized_code.IsNull() && !unoptimized_code.is_optimized());
 
   intptr_t* frame_copy = isolate->deopt_frame_copy();
   intptr_t* cpu_registers_copy = isolate->deopt_cpu_registers_copy();
   double* xmm_registers_copy = isolate->deopt_xmm_registers_copy();
 
   intptr_t deopt_id, deopt_reason, deopt_index;
   GetDeoptIxDescrAtPc(optimized_code, caller_frame->pc(),
                       &deopt_id, &deopt_reason, &deopt_index);
   ASSERT(deopt_id != Isolate::kNoDeoptId);
-  uword continue_at_pc = unoptimized_code.GetDeoptBeforePcAtDeoptId(deopt_id);
+  uword continue_at_pc = 0;
+  if (deopt_reason == kDeoptAtCall) {
+    continue_at_pc = unoptimized_code.GetDeoptAfterPcAtDeoptId(deopt_id);
+  } else {
+    continue_at_pc = unoptimized_code.GetDeoptBeforePcAtDeoptId(deopt_id);
+  }
   ASSERT(continue_at_pc != 0);
   if (FLAG_trace_deopt) {
     OS::Print("  -> continue at %#"Px"\n", continue_at_pc);
     // TODO(srdjan): If we could allow GC, we could print the line where
     // deoptimization occured.
   }
   const Array& deopt_info_array =
       Array::Handle(optimized_code.deopt_info_array());
   ASSERT(!deopt_info_array.IsNull());
   DeoptInfo& deopt_info = DeoptInfo::Handle();
@@ skipping 35 matching lines @@
                 current->slot(),
                 current->value());
     }
 
     delete current;
   }
 }
 
 
 }  // namespace dart