Basic support for tracking smi-only arrays on ia32.

test/mjsunit/element-kind.js

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-// Flags: --allow-natives-syntax
+// Flags: --allow-natives-syntax --smi-only-arrays
 // Test element kind of objects
 
 var element_kind = {
+  fast_smi_only_elements            :  0,
   fast_elements                     :  1,
   fast_double_elements              :  2,
   dictionary_elements               :  3,
   external_byte_elements            :  4,
   external_unsigned_byte_elements   :  5,
   external_short_elements           :  6,
   external_unsigned_short_elements  :  7,
   external_int_elements             :  8,
   external_unsigned_int_elements    :  9,
   external_float_elements           : 10,
   external_double_elements          : 11,
   external_pixel_elements           : 12
 }
 
 // We expect an object to only be of one element kind.
 function assertKind(expected, obj){
+  assertEquals(expected == element_kind.fast_smi_only_elements,
+               %HasFastSmiOnlyElements(obj));
   assertEquals(expected == element_kind.fast_elements,
                %HasFastElements(obj));
   assertEquals(expected == element_kind.fast_double_elements,
                %HasFastDoubleElements(obj));
   assertEquals(expected == element_kind.dictionary_elements,
                %HasDictionaryElements(obj));
   assertEquals(expected == element_kind.external_byte_elements,
                %HasExternalByteElements(obj));
   assertEquals(expected == element_kind.external_unsigned_byte_elements,
                %HasExternalUnsignedByteElements(obj));
@@ skipping 15 matching lines @@
   assertEquals(expected >= element_kind.external_byte_elements,
                %HasExternalArrayElements(obj));
 }
 
 var me = {};
 assertKind(element_kind.fast_elements, me);
 me.dance = 0xD15C0;
 me.drink = 0xC0C0A;
 assertKind(element_kind.fast_elements, me);
 
+var too = [1,2,3];
+assertKind(element_kind.fast_elements, too);

[Jakob Kummerow, 2011/09/16 16:30:34]

Why fast_elements? Don't all arrays start off with fast_smi_only_elements? Maybe
I'm overlooking something.

[danno, 2011/09/21 14:32:04]

Done.

+too.dance = 0xD15C0;
+too.drink = 0xC0C0A;
+assertKind(element_kind.fast_elements, too);
+
+// Make sure the element kind transitions from smionly when a non-smi is stored.
 var you = new Array();
 for(i = 0; i < 1337; i++) {
-  you[i] = i;
+  var val = i;
+  if (i == 1336) {
+    assertKind(element_kind.fast_smi_only_elements, you);

[Yang, 2011/09/19 14:00:15]

This assert does not pass for me when using the raw patch on top of current
bleeding edge.

[danno, 2011/09/21 14:32:04]

I just ran the test on my machine, and it works for me :-)
On 2011/09/19 14:00:15, Yang wrote:

+    val = new Object();
+  }
+  you[i] = val;
 }
 assertKind(element_kind.fast_elements, you);
 
 assertKind(element_kind.dictionary_elements, new Array(0xC0C0A));
 
 // fast_double_elements not yet available
 
 
 assertKind(element_kind.external_byte_elements,           new Int8Array(9001));
 assertKind(element_kind.external_unsigned_byte_elements,  new Uint8Array(007));
 assertKind(element_kind.external_short_elements,          new Int16Array(666));
 assertKind(element_kind.external_unsigned_short_elements, new Uint16Array(42));
 assertKind(element_kind.external_int_elements,            new Int32Array(0xF));
 assertKind(element_kind.external_unsigned_int_elements,   new Uint32Array(23));
 assertKind(element_kind.external_float_elements,          new Float32Array(7));
 assertKind(element_kind.external_double_elements,         new Float64Array(0));
 assertKind(element_kind.external_pixel_elements,          new PixelArray(512));