Fix the order in which ToNumber is called for some Math functions.

Avoid divisions when doing Math.min(0, 0).
https://bugs.webkit.org/show_bug.cgi?id=26978 has been
filed to fix inconsistencies between JSC and V8.
Review URL: http://codereview.chromium.org/149188

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2367 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/math.js

@@ -68,10 +68,12 @@ function MathAtan(x) {
 }
 
 // ECMA 262 - 15.8.2.5
-function MathAtan2(x, y) {
-  if (!IS_NUMBER(x)) x = ToNumber(x);
+// The naming of y and x matches the spec, as does the order in which
+// ToNumber (valueOf) is called.
+function MathAtan2(y, x) {
   if (!IS_NUMBER(y)) y = ToNumber(y);
-  return %Math_atan2(x, y);
+  if (!IS_NUMBER(x)) x = ToNumber(x);
+  return %Math_atan2(y, x);
 }
 
 // ECMA 262 - 15.8.2.6
@@ -117,11 +119,12 @@ function MathLog(x) {
 // ECMA 262 - 15.8.2.11
 function MathMax(arg1, arg2) {  // length == 2
   var r = -$Infinity;
-  for (var i = %_ArgumentsLength() - 1; i >= 0; --i) {
+  var length = %_ArgumentsLength();
+  for (var i = 0; i < length; i++) {
     var n = ToNumber(%_Arguments(i));
     if (NUMBER_IS_NAN(n)) return n;
-    // Make sure +0 is consider greater than -0.
-    if (n > r || (n === 0 && r === 0 && (1 / n) > (1 / r))) r = n;
+    // Make sure +0 is considered greater than -0.
+    if (n > r || (r === 0 && n === 0 && !%_IsSmi(r))) r = n;
   }
   return r;
 }
@@ -129,11 +132,12 @@ function MathMax(arg1, arg2) {  // length == 2
 // ECMA 262 - 15.8.2.12
 function MathMin(arg1, arg2) {  // length == 2
   var r = $Infinity;
-  for (var i = %_ArgumentsLength() - 1; i >= 0; --i) {
+  var length = %_ArgumentsLength();
+  for (var i = 0; i < length; i++) {
     var n = ToNumber(%_Arguments(i));
     if (NUMBER_IS_NAN(n)) return n;
-    // Make sure -0 is consider less than +0.
-    if (n < r || (n === 0 && r === 0 && (1 / n) < (1 / r))) r = n;
+    // Make sure -0 is considered less than +0.
+    if (n < r || (r === 0 && n === 0 && !%_IsSmi(n))) r = n;
   }
   return r;
 }

test/mjsunit/to_number_order.js

+var x = "";
+var v = new Object();
+var w = new Object();
+var vv = function() { x += "hest"; return 1; }
+var ww = function() { x += "fisk"; return 2; }
+v.valueOf = vv;
+w.valueOf = ww;
+assertEquals(1, Math.min(v,w));
+assertEquals("hestfisk", x, "min");
+
+x = "";
+assertEquals(2, Math.max(v,w));
+assertEquals("hestfisk", x, "max");
+
+x = "";
+assertEquals(Math.atan2(1, 2), Math.atan2(v, w));
+// JSC says fiskhest.
+assertEquals("hestfisk", x, "atan2");
+
+x = "";
+assertEquals(1, Math.pow(v, w));
+assertEquals("hestfisk", x, "pow");
+
+var year = { valueOf: function() { x += 1; return 2007; } };
+var month = { valueOf: function() { x += 2; return 2; } };
+var date = { valueOf: function() { x += 3; return 4; } };
+var hours = { valueOf: function() { x += 4; return 13; } };
+var minutes = { valueOf: function() { x += 5; return 50; } };
+var seconds = { valueOf: function() { x += 6; return 0; } };
+var ms = { valueOf: function() { x += 7; return 999; } };
+
+x = "";
+new Date(year, month, date, hours, minutes, seconds, ms);
+// JSC fails this one: Returns 12345671234567.
+assertEquals("1234567", x, "Date");
+
+x = "";
+Date(year, month, date, hours, minutes, seconds, ms);
+assertEquals("", x, "Date not constructor");
+
+x = "";
+Date.UTC(year, month, date, hours, minutes, seconds, ms);
+// JSC fails this one: Returns 12345671234567.
+assertEquals("1234567", x, "Date.UTC");
+
+x = "";
+new Date().setSeconds(seconds, ms);
+assertEquals("67", x, "Date.UTC");
+
+x = "";
+new Date().setSeconds(seconds, ms);
+assertEquals("67", x, "Date.setSeconds");
+
+x = "";
+new Date().setUTCSeconds(seconds, ms);
+assertEquals("67", x, "Date.setUTCSeconds");
+
+x = "";
+new Date().setMinutes(minutes, seconds, ms);
+assertEquals("567", x, "Date.setMinutes");
+
+x = "";
+new Date().setUTCMinutes(minutes, seconds, ms);
+assertEquals("567", x, "Date.setUTCMinutes");
+
+x = "";
+new Date().setHours(hours, minutes, seconds, ms);
+assertEquals("4567", x, "Date.setHours");
+
+x = "";
+new Date().setUTCHours(hours, minutes, seconds, ms);
+assertEquals("4567", x, "Date.setUTCHours");
+
+x = "";
+new Date().setDate(date, hours, minutes, seconds, ms);
+assertEquals("3", x, "Date.setDate");
+
+x = "";
+new Date().setUTCDate(date, hours, minutes, seconds, ms);
+assertEquals("3", x, "Date.setUTCDate");
+
+x = "";
+new Date().setMonth(month, date, hours, minutes, seconds, ms);
+assertEquals("23", x, "Date.setMonth");
+
+x = "";
+new Date().setUTCMonth(month, date, hours, minutes, seconds, ms);
+assertEquals("23", x, "Date.setUTCMonth");
+
+x = "";
+new Date().setFullYear(year, month, date, hours, minutes, seconds, ms);
+assertEquals("123", x, "Date.setFullYear");
+
+x = "";
+new Date().setUTCFullYear(year, month, date, hours, minutes, seconds, ms);
+assertEquals("123", x, "Date.setUTCFullYear");
+
+var a = { valueOf: function() { x += "hest"; return 97; } };
+var b = { valueOf: function() { x += "fisk"; return 98; } };
+assertEquals("ab", String.fromCharCode(a, b), "String.fromCharCode");
+
+print("ok");