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

runtime/vm/stack_frame.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/stack_frame.h"
 
 #include "platform/memory_sanitizer.h"
 #include "vm/assembler.h"
 #include "vm/deopt_instructions.h"
 #include "vm/isolate.h"
 #include "vm/object.h"
 #include "vm/object_store.h"
 #include "vm/os.h"
 #include "vm/parser.h"
 #include "vm/raw_object.h"
 #include "vm/reusable_handles.h"
 #include "vm/stub_code.h"
 #include "vm/visitor.h"
 
 namespace dart {
 
 
 bool StackFrame::IsStubFrame() const {
   ASSERT(!(IsEntryFrame() || IsExitFrame()));
-  return (LookupDartCode() == Code::null());
+  uword saved_pc =
+      *(reinterpret_cast<uword*>(fp() + (kPcMarkerSlotFromFp * kWordSize)));
+  return (saved_pc == 0);
 }
 
 
 const char* StackFrame::ToCString() const {
   ASSERT(isolate_ == Isolate::Current());
   Zone* zone = Thread::Current()->zone();
   if (IsDartFrame()) {
     const Code& code = Code::Handle(LookupDartCode());
     ASSERT(!code.IsNull());
     const Object& owner = Object::Handle(code.owner());
@@ skipping 130 matching lines @@
 }
 
 
 RawCode* StackFrame::LookupDartCode() const {
   ASSERT(isolate_ == Isolate::Current());
   // We add a no gc scope to ensure that the code below does not trigger
   // a GC as we are handling raw object references here. It is possible
   // that the code is called while a GC is in progress, that is ok.
   NoSafepointScope no_safepoint;
   RawCode* code = GetCodeObject();
-  if ((code != Code::null()) &&
-      (code->ptr()->owner_->GetClassId() == kFunctionCid)) {
-    return code;
-  }
-  return Code::null();
+  ASSERT(code == Code::null() || code->ptr()->owner_ != Function::null());
+  return code;
 }
 
 
 RawCode* StackFrame::GetCodeObject() const {
   // We add a no gc scope to ensure that the code below does not trigger
   // a GC as we are handling raw object references here. It is possible
   // that the code is called while a GC is in progress, that is ok.
   NoSafepointScope no_safepoint;
   const uword pc_marker =
       *(reinterpret_cast<uword*>(fp() + (kPcMarkerSlotFromFp * kWordSize)));
-  ASSERT(pc_marker != 0);
-  ASSERT(reinterpret_cast<RawObject*>(pc_marker)->GetClassId() == kCodeCid ||
-         reinterpret_cast<RawObject*>(pc_marker) == Object::null());
-  return reinterpret_cast<RawCode*>(pc_marker);
+  if (pc_marker != 0) {
+    const uword entry_point =
+        (pc_marker - Assembler::EntryPointToPcMarkerOffset());
+    RawInstructions* instr = Instructions::FromEntryPoint(entry_point);
+    if (instr != Instructions::null()) {
+      return instr->ptr()->code_;
+    }
+  }
+  return Code::null();
 }
 
 
 bool StackFrame::FindExceptionHandler(Isolate* isolate,
                                       uword* handler_pc,
                                       bool* needs_stacktrace,
                                       bool* has_catch_all) const {
   REUSABLE_CODE_HANDLESCOPE(isolate);
   Code& code = reused_code_handle.Handle();
   code = LookupDartCode();
@@ skipping 283 matching lines @@
     if (deopt_instr->kind() == DeoptInstr::kCallerFp) {
       return (index - num_materializations_);
     }
   }
   UNREACHABLE();
   return 0;
 }
 
 
 }  // namespace dart