Canonicalize NaNs on store to Fast(Float|Double) arrays

test/mjsunit/regress/regress-2596.js

Index: test/mjsunit/regress/regress-2596.js
diff --git a/test/mjsunit/compiler/regress-const.js b/test/mjsunit/regress/regress-2596.js
similarity index 73%
copy from test/mjsunit/compiler/regress-const.js
copy to test/mjsunit/regress/regress-2596.js
index aa55d0fd3ae17051a084a6bf28c2257f2abc8495..201b88ac99b31330b19951c58357ef6fa5432214 100644
--- a/test/mjsunit/compiler/regress-const.js
+++ b/test/mjsunit/regress/regress-2596.js
@@ -27,42 +27,30 @@
 
 // Flags: --allow-natives-syntax
 
-// Test const initialization and assignments.
-function f() {
-  var x = 42;
-  while (true) {
-    const y = x;
-    if (--x == 0) return y;
-  }
+var bytes = new Uint8Array([
+    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x7f]);  // kHoleNaN
+var doubles = new Float64Array(bytes.buffer);
+assertTrue(isNaN(doubles[0]));
+
+var prototype = [2.5, 2.5];
+var array = [3.5, 3.5];
+array.__proto__ = prototype;
+assertTrue(%HasFastDoubleElements(array));
+
+function boom(index) {
+  array[index] = doubles[0];
+  return array[index];
 }
 
-function g() {
-  const x = 42;
-  x += 1;
-  return x;
-}
-
-for (var i = 0; i < 5; i++) {
-  f();
-  g();
-}
-
-%OptimizeFunctionOnNextCall(f);
-%OptimizeFunctionOnNextCall(g);
+assertTrue(isNaN(boom(0)));
+assertTrue(isNaN(boom(0)));
+assertTrue(isNaN(boom(0)));
 
-assertEquals(42, f());
-assertEquals(42, g());
-
-
-function h(a, b) {
-  var r = a + b;
-  const X = 42;
-  return r + X;
-}
+// Test hydrogen
+%OptimizeFunctionOnNextCall(boom);
+assertTrue(isNaN(boom(0)));
+assertTrue(isNaN(boom(0)));
+assertTrue(isNaN(boom(0)));
 
-for (var i = 0; i < 5; i++) h(1,2);
 
-%OptimizeFunctionOnNextCall(h);
 
-assertEquals(45, h(1,2));
-assertEquals("foo742", h("foo", 7));