Clean up JSConstructStub

src/arm/builtins-arm.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #if V8_TARGET_ARCH_ARM
 
 #include "src/codegen.h"
 #include "src/debug.h"
@@ skipping 428 matching lines @@
       if (create_memento) {
         __ add(r3, r3, Operand(AllocationMemento::kSize / kPointerSize));
       }
 
       __ Allocate(r3, r4, r5, r6, &rt_call, SIZE_IN_WORDS);
 
       // Allocated the JSObject, now initialize the fields. Map is set to
       // initial map and properties and elements are set to empty fixed array.
       // r1: constructor function
       // r2: initial map
-      // r3: object size (not including memento if create_memento)
+      // r3: object size (including memento if create_memento)
       // r4: JSObject (not tagged)
       __ LoadRoot(r6, Heap::kEmptyFixedArrayRootIndex);
       __ mov(r5, r4);
       DCHECK_EQ(0 * kPointerSize, JSObject::kMapOffset);
       __ str(r2, MemOperand(r5, kPointerSize, PostIndex));
       DCHECK_EQ(1 * kPointerSize, JSObject::kPropertiesOffset);
       __ str(r6, MemOperand(r5, kPointerSize, PostIndex));
       DCHECK_EQ(2 * kPointerSize, JSObject::kElementsOffset);
       __ str(r6, MemOperand(r5, kPointerSize, PostIndex));
 
@@ skipping 53 matching lines @@
         __ InitializeFieldsWithFiller(r5, r0, r6);
       }
 
       // Add the object tag to make the JSObject real, so that we can continue
       // and jump into the continuation code at any time from now on. Any
       // failures need to undo the allocation, so that the heap is in a
       // consistent state and verifiable.
       __ add(r4, r4, Operand(kHeapObjectTag));
 
       // Check if a non-empty properties array is needed. Continue with
-      // allocated object if not fall through to runtime call if it is.
+      // allocated object if not; allocate and initialize a FixedArray if yes.
       // r1: constructor function
       // r4: JSObject
       // r5: start of next object (not tagged)
       __ ldrb(r3, FieldMemOperand(r2, Map::kUnusedPropertyFieldsOffset));
       // The field instance sizes contains both pre-allocated property fields
       // and in-object properties.
       __ ldr(r0, FieldMemOperand(r2, Map::kInstanceSizesOffset));
       __ Ubfx(r6, r0, Map::kPreAllocatedPropertyFieldsByte * kBitsPerByte,
               kBitsPerByte);
       __ add(r3, r3, Operand(r6));
@@ skipping 34 matching lines @@
       __ str(r0, MemOperand(r2, kPointerSize, PostIndex));
 
       // Initialize the fields to undefined.
       // r1: constructor function
       // r2: First element of FixedArray (not tagged)
       // r3: number of elements in properties array
       // r4: JSObject
       // r5: FixedArray (not tagged)
       __ add(r6, r2, Operand(r3, LSL, kPointerSizeLog2));  // End of object.
       DCHECK_EQ(2 * kPointerSize, FixedArray::kHeaderSize);
-      { Label loop, entry;
-        __ LoadRoot(r0, Heap::kUndefinedValueRootIndex);
-        __ b(&entry);
-        __ bind(&loop);
-        __ str(r0, MemOperand(r2, kPointerSize, PostIndex));
-        __ bind(&entry);
-        __ cmp(r2, r6);
-        __ b(lt, &loop);
-      }
+      __ LoadRoot(r0, Heap::kUndefinedValueRootIndex);
+      __ InitializeFieldsWithFiller(r2, r6, r0);
 
       // Store the initialized FixedArray into the properties field of
       // the JSObject
       // r1: constructor function
       // r4: JSObject
       // r5: FixedArray (not tagged)
       __ add(r5, r5, Operand(kHeapObjectTag));  // Add the heap tag.
       __ str(r5, FieldMemOperand(r4, JSObject::kPropertiesOffset));
 
       // Continue with JSObject being successfully allocated
@@ skipping 1213 matching lines @@
   }
 }
 
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_ARM