Small refactor to KeyedStoreIC::GenerateGeneric to make it slightly faster.

src/arm/ic-arm.cc

 // Copyright 2011 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 1342 matching lines @@
 
   // Check the key against the length in the array.
   __ ldr(ip, FieldMemOperand(receiver, JSArray::kLengthOffset));
   __ cmp(key, Operand(ip));
   __ b(hs, &extra);
   // Fall through to fast case.
 
   __ bind(&fast);
   Register scratch_value = r4;
   Register address = r5;
+
+  Label non_smi_value;
+  __ JumpIfNotSmi(value, &non_smi_value);
+  // It's irrelevant whether array is smi-only or not when writing a smi.
+  __ add(address, elements,

[Rico, 2011/09/24 18:40:36]

fits on one line

+         Operand(FixedArray::kHeaderSize - kHeapObjectTag));
+  __ add(address, address, Operand(key, LSL, kPointerSizeLog2 - kSmiTagSize));
+  __ str(value, MemOperand(address));
+  __ Ret();
+
+  __ bind(&non_smi_value);
   if (FLAG_smi_only_arrays) {
-    Label not_smi_only;
     // Make sure the elements are smi-only.

[Rico, 2011/09/24 18:40:36]

Comment seems wrong now, that is not what we check anymore.
Probably something like:
// If this is a smi only array call runtime.
(or be more generic if you like, this might not be Danno's last array type
specialization :-) )

     __ ldr(scratch_value, FieldMemOperand(receiver, HeapObject::kMapOffset));
-    __ CheckFastSmiOnlyElements(scratch_value, scratch_value, &not_smi_only);
-    // Non-smis need to call into the runtime if the array is smi only.
-    __ JumpIfNotSmi(value, &slow);
-    __ add(address, elements,
-           Operand(FixedArray::kHeaderSize - kHeapObjectTag));
-    __ add(address, address, Operand(key, LSL, kPointerSizeLog2 - kSmiTagSize));
-    __ str(value, MemOperand(address));
-    __ Ret();
-    __ bind(&not_smi_only);
+    __ CheckFastObjectElements(scratch_value, scratch_value, &slow);
   }
-  // Fast case, store the value to the elements backing store.
+  // Fast elements array, store the value to the elements backing store.
   __ add(address, elements, Operand(FixedArray::kHeaderSize - kHeapObjectTag));
   __ add(address, address, Operand(key, LSL, kPointerSizeLog2 - kSmiTagSize));
   __ str(value, MemOperand(address));
-  // Skip write barrier if the written value is a smi.
-  __ tst(value, Operand(kSmiTagMask));
-  __ Ret(eq);
-
   // Update write barrier for the elements array address.
   __ mov(scratch_value, value);  // Preserve the value which is returned.
   __ RecordWrite(elements,
                  address,
                  scratch_value,
                  kLRHasNotBeenSaved,
                  kDontSaveFPRegs,
                  EMIT_REMEMBERED_SET,
                  OMIT_SMI_CHECK);
-
   __ Ret();
 }
 
 
 void StoreIC::GenerateMegamorphic(MacroAssembler* masm,
                                   StrictModeFlag strict_mode) {
   // ----------- S t a t e -------------
   //  -- r0    : value
   //  -- r1    : receiver
   //  -- r2    : name
@@ skipping 240 matching lines @@
     Register reg = Assembler::GetRn(instr_at_patch);
     patcher.masm()->tst(reg, Operand(kSmiTagMask));
     patcher.EmitCondition(eq);
   }
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM