Improvement to SmiLexicalCompare

test/mjsunit/array-sort.js

 // Copyright 2010 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 52 matching lines @@
   a = [1230, 123].sort();
   assertArrayEquals([123, 1230], a);
   a = [1231, 123].sort();
   assertArrayEquals([123, 1231], a);
 
   // Default sort on Smis and non-Smis.
   a = [1000000000, 10000000000, 1000000001, -1000000000, -10000000000, -1000000001];
   a.sort();
   assertArrayEquals([-1000000000, -10000000000, -1000000001, 1000000000, 10000000000, 1000000001], a);
 
+  // Other cases are tested implicitly in TestSmiLexicographicCompare.
+}
 
-  for (var xb = 1; xb <= 1000 * 1000 * 1000; xb *= 10) {
+TestNumberSort();
+
+function TestSmiLexicographicCompare() {
+
+  assertFalse(%_IsSmi(2147483648), 'Update test for >32 bit Smi');
+
+  // Collect a list of interesting Smis.
+  var seen = {};
+  var smis = [];
+  function add(x) {
+    if (x | 0 == x) {
+      x = x | 0;  // Canonicalizes to Smi if 32-bit signed and fits in Smi.
+    }
+    if (%_IsSmi(x) && !seen[x]) {
+      seen[x] = 1;
+      smis.push(x);
+    }
+  }
+  function addSigned(x) {
+    add(x);
+    add(-x);
+  }
+
+  var BIGGER_THAN_ANY_SMI = 10 * 1000 * 1000 * 1000;
+  for (var xb = 1; xb <= BIGGER_THAN_ANY_SMI; xb *= 10) {
     for (var xf = 0; xf <= 9; xf++) {
       for (var xo = -1; xo <= 1; xo++) {
-        for (var yb = 1; yb <= 1000 * 1000 * 1000; yb *= 10) {
-          for (var yf = 0; yf <= 9; yf++) {
-            for (var yo = -1; yo <= 1; yo++) {
-              var x = xb * xf + xo;
-              var y = yb * yf + yo;
-              if (!%_IsSmi(x)) continue;
-              if (!%_IsSmi(y)) continue;
-              var lex = %SmiLexicographicCompare(x, y);
-              if (lex < 0) lex = -1;
-              if (lex > 0) lex = 1;
-              assertEquals(lex, (x == y) ? 0 : ((x + "") < (y + "") ? -1 : 1), x + " < " + y);
-            }
-          }
-        }
+        addSigned(xb * xf + xo);
       }
     }
   }
+
+  for (var yb = 1; yb <= BIGGER_THAN_ANY_SMI; yb *= 2) {
+    for (var yo = -2; yo <= 2; yo++) {
+      addSigned(yb + yo);
+    }
+  }
+
+  for (var i = 0; i < smis.length; i++) {
+    for (var j = 0; j < smis.length; j++) {
+      var x = smis[i];
+      var y = smis[j];
+      var lex = %SmiLexicographicCompare(x, y);
+      var expected = (x == y) ? 0 : ((x + "") < (y + "") ? -1 : 1);
+      assertEquals(lex, expected, x + " < " + y);
+    }
+  }
 }
 
-TestNumberSort();
+TestSmiLexicographicCompare();
 
 
 // Test lexicographical string sorting.
 function TestStringSort() {
   var a = [ "cc", "c", "aa", "a", "bb", "b", "ab", "ac" ];
   a.sort();
   assertArrayEquals([ "a", "aa", "ab", "ac", "b", "bb", "c", "cc" ], a);
 }
 
 TestStringSort();
@@ skipping 260 matching lines @@
   return {__proto__: o.prototype, val: v};
 }
 var arr = [o(1), o(2), o(4), o(8), o(16), o(32), o(64), o(128), o(256), o(-0)];
 var global = this;
 function cmpTest(a, b) {
   assertEquals(global, this);
   assertTrue(a instanceof o);
   assertTrue(b instanceof o);
   return a.val - b.val;
 }
-arr.sort(cmpTest);
+arr.sort(cmpTest);