Minor changes to the native array construct code...

src/ia32/builtins-ia32.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 722 matching lines @@
   // Initialize the FixedArray and fill it with holes. FixedArray length is not
   // stored as a smi.
   // result: JSObject
   // scratch1: elements array
   // scratch2: start of next object
   __ mov(FieldOperand(scratch1, JSObject::kMapOffset),
          Factory::fixed_array_map());
   __ mov(FieldOperand(scratch1, Array::kLengthOffset), Immediate(holes));
 
   // Fill the FixedArray with the hole value. Inline the code if short.
-  if (holes <= 4) {
+  // Reconsider loop unfolding if kPreallocatedArrayElements gets changed.
+  static const int kLoopUnfoldLimit = 4;
+  ASSERT(kPreallocatedArrayElements <= kLoopUnfoldLimit);
+  if (holes <= kLoopUnfoldLimit) {
     // Use a scratch register here to have only one reloc info when unfolding
     // the loop.
     __ mov(scratch3, Factory::the_hole_value());
     for (int i = 0; i < holes; i++) {
       __ mov(FieldOperand(scratch1,
                           FixedArray::kHeaderSize + i * kPointerSize),
              scratch3);
     }
   } else {
     Label loop, entry;
@@ skipping 75 matching lines @@
   __ mov(FieldOperand(result, JSArray::kLengthOffset), array_size);
 
   // Calculate the location of the elements array and set elements array member
   // of the JSArray.
   // result: JSObject
   // elements_array_end: start of next object
   // array_size: size of array (smi)
   __ lea(elements_array, Operand(result, JSArray::kSize));
   __ mov(FieldOperand(result, JSArray::kElementsOffset), elements_array);
 
-  // Initialize the fixed array and fill it with holes. FixedArray length is not
-  // stored as a smi.
+  // Initialize the fixed array. FixedArray length is not stored as a smi.
   // result: JSObject
   // elements_array: elements array
   // elements_array_end: start of next object
   // array_size: size of array (smi)
   ASSERT(kSmiTag == 0);
   __ shr(array_size, kSmiTagSize);  // Convert from smi to value.
   __ mov(FieldOperand(elements_array, JSObject::kMapOffset),
          Factory::fixed_array_map());
   Label not_empty_2, fill_array;
   __ test(array_size, Operand(array_size));
@@ skipping 51 matching lines @@
   // Push the constructor and argc. No need to tag argc as a smi, as there will
   // be no garbage collection with this on the stack.
   int push_count = 0;
   if (construct_call) {
     push_count++;
     __ push(edi);
   }
   push_count++;
   __ push(eax);
 
-  // Check for array construction with zero arguments or one.
+  // Check for array construction with zero arguments.
   __ test(eax, Operand(eax));
   __ j(not_zero, &argc_one_or_more);
 
   // Handle construction of an empty array.
   AllocateEmptyJSArray(masm,
                        edi,
                        eax,
                        ebx,
                        ecx,
                        edi,
@@ skipping 75 matching lines @@
   // eax: JSArray
   // ebx: argc
   // edx: elements_array_end (untagged)
   // esp[0]: JSArray
   // esp[4]: return address
   // esp[8]: last argument
 
   // Location of the last argument
   __ lea(edi, Operand(esp, 2 * kPointerSize));
 
-  // Location of the first array element (fill_with_holes is false, so the
-  // FixedArray is returned).
+  // Location of the first array element (Parameter fill_with_holes to
+  // AllocateJSArrayis false, so the FixedArray is returned in ecx).
   __ lea(edx, Operand(ecx, FixedArray::kHeaderSize - kHeapObjectTag));
 
   // ebx: argc
   // edx: location of the first array element
   // edi: location of the last argument
   // esp[0]: JSArray
   // esp[4]: return address
   // esp[8]: last argument
   Label loop, entry;
   __ mov(ecx, ebx);
@@ skipping 41 matching lines @@
   if (FLAG_debug_code) {
     // Initial map for the builtin Array function shoud be a map.
     __ mov(ebx, FieldOperand(edi, JSFunction::kPrototypeOrInitialMapOffset));
     // Will both indicate a NULL and a Smi.
     __ test(ebx, Immediate(kSmiTagMask));
     __ Assert(not_zero, "Unexpected initial map for Array function");
     __ CmpObjectType(ebx, MAP_TYPE, ecx);
     __ Assert(equal, "Unexpected initial map for Array function");
   }
 
-  // Run the native code for the Array function called as constructor.
+  // Run the native code for the Array function called as a normal function.
   ArrayNativeCode(masm, false, &generic_array_code);
 
   // Jump to the generic array code in case the specialized code cannot handle
   // the construction.
   __ bind(&generic_array_code);
   Code* code = Builtins::builtin(Builtins::ArrayCodeGeneric);
   Handle<Code> array_code(code);
   __ jmp(array_code, RelocInfo::CODE_TARGET);
 }
 
@@ skipping 16 matching lines @@
     // Initial map for the builtin Array function should be a map.
     __ mov(ebx, FieldOperand(edi, JSFunction::kPrototypeOrInitialMapOffset));
     // Will both indicate a NULL and a Smi.
     __ test(ebx, Immediate(kSmiTagMask));
     __ Assert(not_zero, "Unexpected initial map for Array function");
     __ CmpObjectType(ebx, MAP_TYPE, ecx);
     __ Assert(equal, "Unexpected initial map for Array function");
   }
 
   // Run the native code for the Array function called as constructor.
-  ArrayNativeCode(masm, false, &generic_constructor);
+  ArrayNativeCode(masm, true, &generic_constructor);
 
   // Jump to the generic construct code in case the specialized code cannot
   // handle the construction.
   __ bind(&generic_constructor);
-  GenerateLoadArrayFunction(masm, edi);
   Code* code = Builtins::builtin(Builtins::JSConstructStubGeneric);
   Handle<Code> generic_construct_stub(code);
   __ jmp(generic_construct_stub, RelocInfo::CODE_TARGET);
 }
 
 
 static void EnterArgumentsAdaptorFrame(MacroAssembler* masm) {
   __ push(ebp);
   __ mov(ebp, Operand(esp));
 
@@ skipping 103 matching lines @@
   // Dont adapt arguments.
   // -------------------------------------------
   __ bind(&dont_adapt_arguments);
   __ jmp(Operand(edx));
 }
 
 
 #undef __
 
 } }  // namespace v8::internal