Handle single element array growth + transition in generic KeyedStoreIC

src/ia32/ic-ia32.cc

-// Copyright 2011 the V8 project authors. All rights reserved.
+// Copyright 2012 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
 //       with the distribution.
@@ skipping 746 matching lines @@
 void KeyedStoreIC::GenerateGeneric(MacroAssembler* masm,
                                    StrictModeFlag strict_mode) {
   // ----------- S t a t e -------------
   //  -- eax    : value
   //  -- ecx    : key
   //  -- edx    : receiver
   //  -- esp[0] : return address
   // -----------------------------------
   Label slow, fast_object_with_map_check, fast_object_without_map_check;
   Label fast_double_with_map_check, fast_double_without_map_check;
-  Label check_if_double_array, array, extra;
+  Label check_if_double_array, array, extra, transition_smi_elements;
+  Label finish_object_store, non_double_value, transition_double_elements;
 
   // Check that the object isn't a smi.
   __ JumpIfSmi(edx, &slow);
   // Get the map from the receiver.
   __ mov(edi, FieldOperand(edx, HeapObject::kMapOffset));
   // Check that the receiver does not require access checks.  We need
   // to do this because this generic stub does not perform map checks.
   __ test_b(FieldOperand(edi, Map::kBitFieldOffset),
             1 << Map::kIsAccessCheckNeeded);
   __ j(not_zero, &slow);
@@ skipping 76 matching lines @@
   __ j(not_equal, &fast_double_with_map_check);
   __ bind(&fast_object_without_map_check);
   // Smi stores don't require further checks.
   Label non_smi_value;
   __ JumpIfNotSmi(eax, &non_smi_value);
   // It's irrelevant whether array is smi-only or not when writing a smi.
   __ mov(CodeGenerator::FixedArrayElementOperand(ebx, ecx), eax);
   __ ret(0);
 
   __ bind(&non_smi_value);
-  // Escape to slow case when writing non-smi into smi-only array.
+  // Escape to elements kind transition case.
   __ mov(edi, FieldOperand(edx, HeapObject::kMapOffset));
-  __ CheckFastObjectElements(edi, &slow, Label::kNear);
+  __ CheckFastObjectElements(edi, &transition_smi_elements);
 
   // Fast elements array, store the value to the elements backing store.
+  __ bind(&finish_object_store);
   __ mov(CodeGenerator::FixedArrayElementOperand(ebx, ecx), eax);
   // Update write barrier for the elements array address.
   __ mov(edx, eax);  // Preserve the value which is returned.
   __ RecordWriteArray(
       ebx, edx, ecx, kDontSaveFPRegs, EMIT_REMEMBERED_SET, OMIT_SMI_CHECK);
   __ ret(0);
 
   __ bind(&fast_double_with_map_check);
   // Check for fast double array case. If this fails, call through to the
   // runtime.
   __ cmp(edi, masm->isolate()->factory()->fixed_double_array_map());
   __ j(not_equal, &slow);
   __ bind(&fast_double_without_map_check);
   // If the value is a number, store it as a double in the FastDoubleElements
   // array.
-  __ StoreNumberToDoubleElements(eax, ebx, ecx, edx, xmm0, &slow, false);
+  __ StoreNumberToDoubleElements(eax, ebx, ecx, edx, xmm0,
+                                 &transition_double_elements, false);
   __ ret(0);
+
+  __ bind(&transition_smi_elements);
+  __ mov(ebx, FieldOperand(edx, HeapObject::kMapOffset));
+
+  // Transition the array appropriately depending on the value type.
+  __ CheckMap(eax,
+              masm->isolate()->factory()->heap_number_map(),
+              &non_double_value,
+              DONT_DO_SMI_CHECK);
+
+  // Value is a double. Transition FAST_SMI_ONLY_ELEMENTS ->
+  // FAST_DOUBLE_ELEMENTS and complete the store.
+  __ LoadTransitionedArrayMapConditional(FAST_SMI_ONLY_ELEMENTS,
+                                         FAST_DOUBLE_ELEMENTS,
+                                         ebx,
+                                         edi,
+                                         &slow);
+  ElementsTransitionGenerator::GenerateSmiOnlyToDouble(masm, &slow);
+  __ mov(ebx, FieldOperand(edx, JSObject::kElementsOffset));
+  __ jmp(&fast_double_without_map_check);
+
+  __ bind(&non_double_value);
+  // Value is not a double, FAST_SMI_ONLY_ELEMENTS -> FAST_ELEMENTS
+  __ LoadTransitionedArrayMapConditional(FAST_SMI_ONLY_ELEMENTS,
+                                         FAST_ELEMENTS,
+                                         ebx,
+                                         edi,
+                                         &slow);
+  ElementsTransitionGenerator::GenerateSmiOnlyToObject(masm);
+  __ mov(ebx, FieldOperand(edx, JSObject::kElementsOffset));
+  __ jmp(&finish_object_store);
+
+  __ bind(&transition_double_elements);
+  // Elements are FAST_DOUBLE_ELEMENTS, but value is an Object that's not a
+  // HeapNumber. Make sure that the receiver is a Array with FAST_ELEMENTS and
+  // transition array from FAST_DOUBLE_ELEMENTS to FAST_ELEMENTS
+  __ mov(ebx, FieldOperand(edx, HeapObject::kMapOffset));
+  __ LoadTransitionedArrayMapConditional(FAST_DOUBLE_ELEMENTS,
+                                         FAST_ELEMENTS,
+                                         ebx,
+                                         edi,
+                                         &slow);
+  ElementsTransitionGenerator::GenerateDoubleToObject(masm, &slow);
+  __ mov(ebx, FieldOperand(edx, JSObject::kElementsOffset));
+  __ jmp(&finish_object_store);
 }
 
 
 // The generated code does not accept smi keys.
 // The generated code falls through if both probes miss.
 void CallICBase::GenerateMonomorphicCacheProbe(MacroAssembler* masm,
                                                int argc,
                                                Code::Kind kind,
                                                Code::ExtraICState extra_state) {
   // ----------- S t a t e -------------
@@ skipping 818 matching lines @@
   Condition cc = *jmp_address == Assembler::kJncShortOpcode
       ? not_zero
       : zero;
   *jmp_address = static_cast<byte>(Assembler::kJccShortPrefix | cc);
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32