Elements kind conversion in generated code (ia32).

test/mjsunit/elements-transition.js

Index: test/mjsunit/elements-transition.js
diff --git a/test/mjsunit/elements-transition.js b/test/mjsunit/elements-transition.js
new file mode 100644
index 0000000000000000000000000000000000000000..77c2aa2c8873f14332dc7641f0d97fd7d4b31c7b
--- /dev/null
+++ b/test/mjsunit/elements-transition.js
@@ -0,0 +1,71 @@
+// 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
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Flags: --allow-natives-syntax --smi-only-arrays
+
+function test(test_double, test_object, set) {
+  var length = 10000;
+  var you = new Array(length);
+  var me = new Array(length);

[Jakob Kummerow, 2011/10/13 09:15:59]

As discussed, please add a comment explaining why every operation here needs to
be performed for two identical arrays.

+
+  assertTrue(%HasFastSmiOnlyElements(you));
+  assertTrue(%HasFastSmiOnlyElements(me));
+  for (var i = 0; i < length; i++) {
+    if (i == (length*0.7 | 0) && test_double) {
+      set(you, i, 0.5);
+      set(me, i, 0.5);
+      assertTrue(%HasFastDoubleElements(you));
+      assertTrue(%HasFastDoubleElements(me));
+    } else if (i == (length*0.8 | 0) && test_object) {
+      set(you, i, 'object');
+      set(me, i, 'object');
+      assertTrue(%HasFastElements(you));
+      assertTrue(%HasFastElements(me));
+    } else {
+      set(you, i, 2*i);
+      set(me, i, 2*i);
+    }
+  }
+
+  for (var i = 0; i < length; i++) {
+    if (i == (length*0.7 | 0) && test_double) {
+      assertEquals(0.5, you[i]);
+      assertEquals(0.5, me[i]);
+    } else if (i == (length*0.8 | 0) && test_object) {
+      assertEquals('object', you[i]);
+      assertEquals('object', me[i]);
+    } else {
+      assertEquals(2*i, me[i]);
+      assertEquals(2*i, you[i]);
+    }
+  }
+}
+
+test(false, false, function(a,i,v){ a[i] = v; });
+test(true,  false, function(a,i,v){ a[i] = v; });
+test(false, true,  function(a,i,v){ a[i] = v; });
+test(true,  true,  function(a,i,v){ a[i] = v; });