Revert "VM: New calling convention for generated code."

runtime/vm/stack_frame_ia32.h

 // Copyright (c) 2013, 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_STACK_FRAME_IA32_H_
 #define VM_STACK_FRAME_IA32_H_
 
 namespace dart {
 
 /* IA32 Dart Frame Layout
 
                |                    | <- TOS
 Callee frame   | ...                |
                | saved EBP          |    (EBP of current frame)
                | saved PC           |    (PC of current frame)
                +--------------------+
 Current frame  | ...               T| <- ESP of current frame
                | first local       T|
-               | code object       T|    (current frame's code object)
+               | PC marker          |    (current frame's code entry + offset)
                | caller's EBP       | <- EBP of current frame
                | caller's ret addr  |    (PC of caller frame)
                +--------------------+
 Caller frame   | last parameter     | <- ESP of caller frame
                |  ...               |
 
                T against a slot indicates it needs to be traversed during GC.
 */
 
 static const int kDartFrameFixedSize = 3;  // PC marker, EBP, PC.
 static const int kSavedPcSlotFromSp = -1;
 
-static const int kFirstObjectSlotFromFp = -1;  // Used by GC to traverse stack.
+static const int kFirstObjectSlotFromFp = -2;  // Used by GC to traverse stack.
 
 static const int kFirstLocalSlotFromFp = -2;
 static const int kPcMarkerSlotFromFp = -1;
 static const int kSavedCallerFpSlotFromFp = 0;
 static const int kSavedCallerPcSlotFromFp = 1;
 static const int kParamEndSlotFromFp = 1;  // One slot past last parameter.
 static const int kCallerSpSlotFromFp = 2;
 
 // No pool pointer on IA32 (indicated by aliasing saved fp).
 static const int kSavedCallerPpSlotFromFp = kSavedCallerFpSlotFromFp;
 
 // Entry and exit frame layout.
 static const int kExitLinkSlotFromEntryFp = -6;
 
 }  // namespace dart
 
 #endif  // VM_STACK_FRAME_IA32_H_