Reland: Improve smi shift operations and avoid repeated deoptimizations.

runtime/vm/deopt_instructions.h

 // 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.
 
 #ifndef VM_DEOPT_INSTRUCTIONS_H_
 #define VM_DEOPT_INSTRUCTIONS_H_
 
 #include "vm/allocation.h"
 #include "vm/assembler.h"
+#include "vm/code_generator.h"
 #include "vm/growable_array.h"
 #include "vm/object.h"
 
 namespace dart {
 
 class Location;
 class Value;
 
 // Holds all data relevant for execution of deoptimization instructions.
 class DeoptimizationContext : public ValueObject {
  public:
   // 'to_frame_start' points to the return address just below the frame's
   // stack pointer. 'num_args' is 0 if there are no arguments or if there
   // are optional arguments.
   DeoptimizationContext(intptr_t* to_frame_start,
                         intptr_t to_frame_size,
                         const Array& object_table,
-                        intptr_t num_args);
+                        intptr_t num_args,
+                        DeoptReasonId deopt_reason);
 
   intptr_t* GetFromFrameAddressAt(intptr_t index) const {
     ASSERT((0 <= index) && (index < from_frame_size_));
     return &from_frame_[index];
   }
 
   intptr_t* GetToFrameAddressAt(intptr_t index) const {
     ASSERT((0 <= index) && (index < to_frame_size_));
     return &to_frame_[index];
   }
@@ skipping 17 matching lines @@
   }
 
   int64_t XmmRegisterValueAsInt64(XmmRegister reg) const {
     return (reinterpret_cast<int64_t*>(xmm_registers_copy_))[reg];
   }
 
   Isolate* isolate() const { return isolate_; }
 
   intptr_t from_frame_size() const { return from_frame_size_; }
 
+  DeoptReasonId deopt_reason() const { return deopt_reason_; }
+
  private:
   const Array& object_table_;
   intptr_t* to_frame_;
   const intptr_t to_frame_size_;
   intptr_t* from_frame_;
   intptr_t from_frame_size_;
   intptr_t* registers_copy_;
   double* xmm_registers_copy_;
   const intptr_t num_args_;
+  const DeoptReasonId deopt_reason_;
   intptr_t caller_fp_;
   Isolate* isolate_;
 
   DISALLOW_COPY_AND_ASSIGN(DeoptimizationContext);
 };
 
 
 
 // Represents one deopt instruction, e.g, setup return address, store object,
 // store register, etc. The target is defined by instruction's position in
@@ skipping 122 matching lines @@
                        DeoptInfo* info,
                        Smi* reason);
 
  private:
   static const intptr_t kEntrySize = 3;
 };
 
 }  // namespace dart
 
 #endif  // VM_DEOPT_INSTRUCTIONS_H_