Bring r5483 "Fix direct loading of global function prototypes" to 2.2.

src/arm/stub-cache-arm.cc

 // Copyright 2006-2009 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 248 matching lines @@
   __ ldr(prototype, MemOperand(prototype, Context::SlotOffset(index)));
   // Load the initial map.  The global functions all have initial maps.
   __ ldr(prototype,
          FieldMemOperand(prototype, JSFunction::kPrototypeOrInitialMapOffset));
   // Load the prototype from the initial map.
   __ ldr(prototype, FieldMemOperand(prototype, Map::kPrototypeOffset));
 }
 
 
 void StubCompiler::GenerateDirectLoadGlobalFunctionPrototype(
-    MacroAssembler* masm, int index, Register prototype) {
+    MacroAssembler* masm, int index, Register prototype, Label* miss) {
+  // Check we're still in the same context.
+  __ ldr(prototype, MemOperand(cp, Context::SlotOffset(Context::GLOBAL_INDEX)));
+  __ Move(ip, Top::global());
+  __ cmp(prototype, ip);
+  __ b(ne, miss);
   // Get the global function with the given index.
   JSFunction* function = JSFunction::cast(Top::global_context()->get(index));
   // Load its initial map. The global functions all have initial maps.
   __ Move(prototype, Handle<Map>(function->initial_map()));
   // Load the prototype from the initial map.
   __ ldr(prototype, FieldMemOperand(prototype, Map::kPrototypeOffset));
 }
 
 
 // Load a fast property out of a holder object (src). In-object properties
@@ skipping 1207 matching lines @@
     case STRING_CHECK:
       if (!function->IsBuiltin()) {
         // Calling non-builtins with a value as receiver requires boxing.
         __ jmp(&miss);
       } else {
         // Check that the object is a two-byte string or a symbol.
         __ CompareObjectType(r1, r3, r3, FIRST_NONSTRING_TYPE);
         __ b(hs, &miss);
         // Check that the maps starting from the prototype haven't changed.
         GenerateDirectLoadGlobalFunctionPrototype(
-            masm(), Context::STRING_FUNCTION_INDEX, r0);
+            masm(), Context::STRING_FUNCTION_INDEX, r0, &miss);
         CheckPrototypes(JSObject::cast(object->GetPrototype()), r0, holder, r3,
                         r1, r4, name, &miss);
       }
       break;
 
     case NUMBER_CHECK: {
       if (!function->IsBuiltin()) {
         // Calling non-builtins with a value as receiver requires boxing.
         __ jmp(&miss);
       } else {
         Label fast;
         // Check that the object is a smi or a heap number.
         __ tst(r1, Operand(kSmiTagMask));
         __ b(eq, &fast);
         __ CompareObjectType(r1, r0, r0, HEAP_NUMBER_TYPE);
         __ b(ne, &miss);
         __ bind(&fast);
         // Check that the maps starting from the prototype haven't changed.
         GenerateDirectLoadGlobalFunctionPrototype(
-            masm(), Context::NUMBER_FUNCTION_INDEX, r0);
+            masm(), Context::NUMBER_FUNCTION_INDEX, r0, &miss);
         CheckPrototypes(JSObject::cast(object->GetPrototype()), r0, holder, r3,
                         r1, r4, name, &miss);
       }
       break;
     }
 
     case BOOLEAN_CHECK: {
       if (!function->IsBuiltin()) {
         // Calling non-builtins with a value as receiver requires boxing.
         __ jmp(&miss);
       } else {
         Label fast;
         // Check that the object is a boolean.
         __ LoadRoot(ip, Heap::kTrueValueRootIndex);
         __ cmp(r1, ip);
         __ b(eq, &fast);
         __ LoadRoot(ip, Heap::kFalseValueRootIndex);
         __ cmp(r1, ip);
         __ b(ne, &miss);
         __ bind(&fast);
         // Check that the maps starting from the prototype haven't changed.
         GenerateDirectLoadGlobalFunctionPrototype(
-            masm(), Context::BOOLEAN_FUNCTION_INDEX, r0);
+            masm(), Context::BOOLEAN_FUNCTION_INDEX, r0, &miss);
         CheckPrototypes(JSObject::cast(object->GetPrototype()), r0, holder, r3,
                         r1, r4, name, &miss);
       }
       break;
     }
 
     default:
       UNREACHABLE();
   }
 
@@ skipping 827 matching lines @@
   // Return the generated code.
   return GetCode();
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM