Create a common subclass for arrays

src/arm/stub-cache-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 3471 matching lines @@
   // have been verified by the caller to not be a smi.
 
   // Check that the key is a smi.
   __ JumpIfNotSmi(key, &miss_force_generic);
 
   __ ldr(r3, FieldMemOperand(receiver, JSObject::kElementsOffset));
   // r3: elements array
 
   // Check that the index is in range.
   __ ldr(ip, FieldMemOperand(r3, ExternalArray::kLengthOffset));
-  __ cmp(ip, Operand(key, ASR, kSmiTagSize));
+  __ cmp(key, ip);
   // Unsigned comparison catches both negative and too-large values.
-  __ b(lo, &miss_force_generic);
+  __ b(hs, &miss_force_generic);
 
   __ ldr(r3, FieldMemOperand(r3, ExternalArray::kExternalPointerOffset));
   // r3: base pointer of external storage
 
   // We are not untagging smi key and instead work with it
   // as if it was premultiplied by 2.
   ASSERT((kSmiTag == 0) && (kSmiTagSize == 1));
 
   Register value = r2;
   switch (elements_kind) {
@@ skipping 302 matching lines @@
   Register key = r1;
   Register receiver = r2;
   // r3 mostly holds the elements array or the destination external array.
 
   // This stub is meant to be tail-jumped to, the receiver must already
   // have been verified by the caller to not be a smi.
 
   __ ldr(r3, FieldMemOperand(receiver, JSObject::kElementsOffset));
 
   // Check that the key is a smi.
   __ JumpIfNotSmi(key, &miss_force_generic);

[Kevin Millikin (Chromium), 2011/08/11 08:13:06]

Moving this check first slightly speeds up the miss case by avoiding the
elements load.

[danno, 2011/08/11 13:59:42]

Done.

 
   // Check that the index is in range
   __ SmiUntag(r4, key);

[Kevin Millikin (Chromium), 2011/08/11 08:13:06]

If you push the untagging down to all the current uses of r4, I think most of
them can avoid the untagging.  (Maybe only the EXTERNAL_FLOAT_ELEMENTS case
can't?)

[danno, 2011/08/11 13:59:42]

Done.

   __ ldr(ip, FieldMemOperand(r3, ExternalArray::kLengthOffset));
-  __ cmp(r4, ip);
+  __ cmp(key, ip);
   // Unsigned comparison catches both negative and too-large values.
   __ b(hs, &miss_force_generic);
 
   // Handle both smis and HeapNumbers in the fast path. Go to the
   // runtime for all other kinds of values.
   // r3: external array.
   // r4: key (integer).
   if (elements_kind == JSObject::EXTERNAL_PIXEL_ELEMENTS) {
     // Double to pixel conversion is only implemented in the runtime for now.
     __ JumpIfNotSmi(value, &slow);
@@ skipping 593 matching lines @@
       masm->isolate()->builtins()->KeyedStoreIC_MissForceGeneric();
   __ Jump(ic, RelocInfo::CODE_TARGET);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM