Add sparse array handling to Array.protoype.indexOf/lastIndexOf.

Review URL: http://codereview.chromium.org/3132046

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5432 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/array.js

@@ -957,14 +957,41 @@ function ArrayIndexOf(element, index) {
     // If index is still negative, search the entire array.
     if (index < 0) index = 0;
   }
+  var min = index;
+  var max = length;
+  if (UseSparseVariant(this, length, true)) {
+    var intervals = %GetArrayKeys(this, length);
+    if (intervals.length == 2 && intervals[0] < 0) {
+      // A single interval.
+      var intervalMin = -(intervals[0] + 1);
+      var intervalMax = intervalMin + intervals[1];
+      min = MAX(min, intervalMin);
+      max = intervalMax;  // Capped by length already.
+      // Fall through to loop below.
+    } else {
+      if (intervals.length == 0) return -1;
+      // Get all the keys in sorted order.
+      var sortedKeys = GetSortedArrayKeys(this, intervals);
+      var n = sortedKeys.length;
+      var i = 0;
+      while (i < n && sortedKeys[i] < index) i++;
+      while (i < n) {
+        var key = sortedKeys[i];
+        if (!IS_UNDEFINED(key) && this[key] === element) return key;
+        i++;
+      }
+      return -1;
+    }
+  }
   // Lookup through the array.
   if (!IS_UNDEFINED(element)) {
-    for (var i = index; i < length; i++) {
+    for (var i = min; i < max; i++) {
       if (this[i] === element) return i;
     }
     return -1;
   }
-  for (var i = index; i < length; i++) {
+  // Lookup through the array.
+  for (var i = min; i < max; i++) {
     if (IS_UNDEFINED(this[i]) && i in this) {
       return i;
     }
@@ -981,19 +1008,43 @@ function ArrayLastIndexOf(element, index) {
   } else {
     index = TO_INTEGER(index);
     // If index is negative, index from end of the array.
-    if (index < 0) index = length + index;
+    if (index < 0) index += length;
     // If index is still negative, do not search the array.
-    if (index < 0) index = -1;
+    if (index < 0) return -1;
     else if (index >= length) index = length - 1;
   }
+  var min = 0;
+  var max = index;
+  if (UseSparseVariant(this, length, true)) {
+    var intervals = %GetArrayKeys(this, index + 1);
+    if (intervals.length == 2 && intervals[0] < 0) {
+      // A single interval.
+      var intervalMin = -(intervals[0] + 1);
+      var intervalMax = intervalMin + intervals[1];
+      min = MAX(min, intervalMin);
+      max = intervalMax;  // Capped by index already.
+      // Fall through to loop below.
+    } else {
+      if (intervals.length == 0) return -1;
+      // Get all the keys in sorted order.
+      var sortedKeys = GetSortedArrayKeys(this, intervals);
+      var i = sortedKeys.length - 1;
+      while (i >= 0) {
+        var key = sortedKeys[i];
+        if (!IS_UNDEFINED(key) && this[key] === element) return key;
+        i--;
+      }
+      return -1;
+    }
+  }
   // Lookup through the array.
   if (!IS_UNDEFINED(element)) {
-    for (var i = index; i >= 0; i--) {
+    for (var i = max; i >= min; i--) {
       if (this[i] === element) return i;
     }
     return -1;
   }
-  for (var i = index; i >= 0; i--) {
+  for (var i = max; i >= min; i--) {
     if (IS_UNDEFINED(this[i]) && i in this) {
       return i;
     }

src/runtime.cc

@@ -8022,8 +8022,10 @@ static Object* Runtime_SwapElements(Arguments args) {
 
 
 // Returns an array that tells you where in the [0, length) interval an array
-// might have elements.  Can either return keys or intervals.  Keys can have
-// gaps in (undefined).  Intervals can also span over some undefined keys.
+// might have elements.  Can either return keys (positive integers) or
+// intervals (pair of a negative integer (-start-1) followed by a
+// positive (length)) or undefined values.
+// Intervals can span over some keys that are not in the object.
 static Object* Runtime_GetArrayKeys(Arguments args) {
   ASSERT(args.length() == 2);
   HandleScope scope;

test/mjsunit/array-indexing.js

@@ -26,41 +26,122 @@
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 var array = [1,2,3,1,2,3,1,2,3,1,2,3];
+var undef_array = [0,,2,undefined,4,,6,undefined,8,,10];
+// Sparse arrays with lenght 42000.
+var sparse_array = [];
+sparse_array[100] = 3;
+sparse_array[200] = undefined;
+sparse_array[300] = 4;
+sparse_array[400] = 5;
+sparse_array[500] = 6;
+sparse_array[600] = 5;
+sparse_array[700] = 4;
+sparse_array[800] = undefined;
+sparse_array[900] = 3
+sparse_array[41999] = "filler";
 
 // ----------------------------------------------------------------------
 // Array.prototype.indexOf.
 // ----------------------------------------------------------------------
 
 // Negative cases.
-assertEquals([].indexOf(1), -1);
-assertEquals(array.indexOf(4), -1);
-assertEquals(array.indexOf(3, array.length), -1);
+assertEquals(-1, [].indexOf(1));
+assertEquals(-1, array.indexOf(4));
+assertEquals(-1, array.indexOf(3, array.length));
 
-assertEquals(array.indexOf(3), 2);
+assertEquals(2, array.indexOf(3));
 // Negative index out of range.
-assertEquals(array.indexOf(1, -17), 0);
+assertEquals(0, array.indexOf(1, -17));
 // Negative index in rage.
-assertEquals(array.indexOf(1, -11), 3);
+assertEquals(3, array.indexOf(1, -11));
 // Index in range.
-assertEquals(array.indexOf(1, 1), 3);
-assertEquals(array.indexOf(1, 3), 3);
-assertEquals(array.indexOf(1, 4), 6);
+assertEquals(3, array.indexOf(1, 1));
+assertEquals(3, array.indexOf(1, 3));
+assertEquals(6, array.indexOf(1, 4));
+
+// Find undefined, not holes.
+assertEquals(3, undef_array.indexOf(undefined));
+assertEquals(3, undef_array.indexOf(undefined, 3));
+assertEquals(7, undef_array.indexOf(undefined, 4));
+assertEquals(7, undef_array.indexOf(undefined, 7));
+assertEquals(-1, undef_array.indexOf(undefined, 8));
+assertEquals(3, undef_array.indexOf(undefined, -11));
+assertEquals(3, undef_array.indexOf(undefined, -8));
+assertEquals(7, undef_array.indexOf(undefined, -7));
+assertEquals(7, undef_array.indexOf(undefined, -4));
+assertEquals(-1, undef_array.indexOf(undefined, -3));
+
+// Find in sparse array.
+assertEquals(100, sparse_array.indexOf(3));
+assertEquals(900, sparse_array.indexOf(3, 101));
+assertEquals(-1, sparse_array.indexOf(3, 901));
+assertEquals(100, sparse_array.indexOf(3, -42000));
+assertEquals(900, sparse_array.indexOf(3, 101 - 42000));
+assertEquals(-1, sparse_array.indexOf(3, 901 - 42000));
+
+assertEquals(300, sparse_array.indexOf(4));
+assertEquals(700, sparse_array.indexOf(4, 301));
+assertEquals(-1, sparse_array.indexOf(4, 701));
+assertEquals(300, sparse_array.indexOf(4, -42000));
+assertEquals(700, sparse_array.indexOf(4, 301 - 42000));
+assertEquals(-1, sparse_array.indexOf(4, 701 - 42000));
+
+assertEquals(200, sparse_array.indexOf(undefined));
+assertEquals(800, sparse_array.indexOf(undefined, 201));
+assertEquals(-1, sparse_array.indexOf(undefined, 801));
+assertEquals(200, sparse_array.indexOf(undefined, -42000));
+assertEquals(800, sparse_array.indexOf(undefined, 201 - 42000));
+assertEquals(-1, sparse_array.indexOf(undefined, 801 - 42000));
+
 
 // ----------------------------------------------------------------------
 // Array.prototype.lastIndexOf.
 // ----------------------------------------------------------------------
 
 // Negative cases.
-assertEquals([].lastIndexOf(1), -1);
-assertEquals(array.lastIndexOf(1, -17), -1);
+assertEquals(-1, [].lastIndexOf(1));
+assertEquals(-1, array.lastIndexOf(1, -17));
 
-assertEquals(array.lastIndexOf(1), 9);
+assertEquals(9, array.lastIndexOf(1));
 // Index out of range.
-assertEquals(array.lastIndexOf(1, array.length), 9);
+assertEquals(9, array.lastIndexOf(1, array.length));
 // Index in range.
-assertEquals(array.lastIndexOf(1, 2), 0);
-assertEquals(array.lastIndexOf(1, 4), 3);
-assertEquals(array.lastIndexOf(1, 3), 3);
+assertEquals(0, array.lastIndexOf(1, 2));
+assertEquals(3, array.lastIndexOf(1, 4));
+assertEquals(3, array.lastIndexOf(1, 3));
 // Negative index in range.
-assertEquals(array.lastIndexOf(1, -11), 0);
+assertEquals(0, array.lastIndexOf(1, -11));
+
+// Find undefined, not holes.
+assertEquals(7, undef_array.lastIndexOf(undefined));
+assertEquals(-1, undef_array.lastIndexOf(undefined, 2));
+assertEquals(3, undef_array.lastIndexOf(undefined, 3));
+assertEquals(3, undef_array.lastIndexOf(undefined, 6));
+assertEquals(7, undef_array.lastIndexOf(undefined, 7));
+assertEquals(7, undef_array.lastIndexOf(undefined, -1));
+assertEquals(-1, undef_array.lastIndexOf(undefined, -9));
+assertEquals(3, undef_array.lastIndexOf(undefined, -8));
+assertEquals(3, undef_array.lastIndexOf(undefined, -5));
+assertEquals(7, undef_array.lastIndexOf(undefined, -4));
+
+// Find in sparse array.
+assertEquals(900, sparse_array.lastIndexOf(3));
+assertEquals(100, sparse_array.lastIndexOf(3, 899));
+assertEquals(-1, sparse_array.lastIndexOf(3, 99));
+assertEquals(900, sparse_array.lastIndexOf(3, -1));
+assertEquals(100, sparse_array.lastIndexOf(3, 899 - 42000));
+assertEquals(-1, sparse_array.lastIndexOf(3, 99 - 42000));
+
+assertEquals(700, sparse_array.lastIndexOf(4));
+assertEquals(300, sparse_array.lastIndexOf(4, 699));
+assertEquals(-1, sparse_array.lastIndexOf(4, 299));
+assertEquals(700, sparse_array.lastIndexOf(4, -1));
+assertEquals(300, sparse_array.lastIndexOf(4, 699 - 42000));
+assertEquals(-1, sparse_array.lastIndexOf(4, 299 - 42000));
 
+assertEquals(800, sparse_array.lastIndexOf(undefined));
+assertEquals(200, sparse_array.lastIndexOf(undefined, 799));
+assertEquals(-1, sparse_array.lastIndexOf(undefined, 199));
+assertEquals(800, sparse_array.lastIndexOf(undefined, -1));
+assertEquals(200, sparse_array.lastIndexOf(undefined, 799 - 42000));
+assertEquals(-1, sparse_array.lastIndexOf(undefined, 199 - 42000));