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-rw-r--r--deps/v8/src/array.js151
1 files changed, 88 insertions, 63 deletions
diff --git a/deps/v8/src/array.js b/deps/v8/src/array.js
index a1cc5b6a7d..1cedd8d476 100644
--- a/deps/v8/src/array.js
+++ b/deps/v8/src/array.js
@@ -777,78 +777,103 @@ function ArraySort(comparefn) {
}
};
- var QuickSort = function QuickSort(a, from, to) {
- // Insertion sort is faster for short arrays.
- if (to - from <= 10) {
- InsertionSort(a, from, to);
- return;
+ var GetThirdIndex = function(a, from, to) {
+ var t_array = [];
+ // Use both 'from' and 'to' to determine the pivot candidates.
+ var increment = 200 + ((to - from) & 15);
+ for (var i = from + 1; i < to - 1; i += increment) {
+ t_array.push([i, a[i]]);
}
- // Find a pivot as the median of first, last and middle element.
- var v0 = a[from];
- var v1 = a[to - 1];
- var middle_index = from + ((to - from) >> 1);
- var v2 = a[middle_index];
- var c01 = %_CallFunction(receiver, v0, v1, comparefn);
- if (c01 > 0) {
- // v1 < v0, so swap them.
- var tmp = v0;
- v0 = v1;
- v1 = tmp;
- } // v0 <= v1.
- var c02 = %_CallFunction(receiver, v0, v2, comparefn);
- if (c02 >= 0) {
- // v2 <= v0 <= v1.
- var tmp = v0;
- v0 = v2;
- v2 = v1;
- v1 = tmp;
- } else {
- // v0 <= v1 && v0 < v2
- var c12 = %_CallFunction(receiver, v1, v2, comparefn);
- if (c12 > 0) {
- // v0 <= v2 < v1
- var tmp = v1;
- v1 = v2;
- v2 = tmp;
+ t_array.sort(function(a, b) {
+ return %_CallFunction(receiver, a[1], b[1], comparefn) } );
+ var third_index = t_array[t_array.length >> 1][0];
+ return third_index;
+ }
+
+ var QuickSort = function QuickSort(a, from, to) {
+ var third_index = 0;
+ while (true) {
+ // Insertion sort is faster for short arrays.
+ if (to - from <= 10) {
+ InsertionSort(a, from, to);
+ return;
}
- }
- // v0 <= v1 <= v2
- a[from] = v0;
- a[to - 1] = v2;
- var pivot = v1;
- var low_end = from + 1; // Upper bound of elements lower than pivot.
- var high_start = to - 1; // Lower bound of elements greater than pivot.
- a[middle_index] = a[low_end];
- a[low_end] = pivot;
-
- // From low_end to i are elements equal to pivot.
- // From i to high_start are elements that haven't been compared yet.
- partition: for (var i = low_end + 1; i < high_start; i++) {
- var element = a[i];
- var order = %_CallFunction(receiver, element, pivot, comparefn);
- if (order < 0) {
- a[i] = a[low_end];
- a[low_end] = element;
- low_end++;
- } else if (order > 0) {
- do {
- high_start--;
- if (high_start == i) break partition;
- var top_elem = a[high_start];
- order = %_CallFunction(receiver, top_elem, pivot, comparefn);
- } while (order > 0);
- a[i] = a[high_start];
- a[high_start] = element;
+ if (to - from > 1000) {
+ third_index = GetThirdIndex(a, from, to);
+ } else {
+ third_index = from + ((to - from) >> 1);
+ }
+ // Find a pivot as the median of first, last and middle element.
+ var v0 = a[from];
+ var v1 = a[to - 1];
+ var v2 = a[third_index];
+ var c01 = %_CallFunction(receiver, v0, v1, comparefn);
+ if (c01 > 0) {
+ // v1 < v0, so swap them.
+ var tmp = v0;
+ v0 = v1;
+ v1 = tmp;
+ } // v0 <= v1.
+ var c02 = %_CallFunction(receiver, v0, v2, comparefn);
+ if (c02 >= 0) {
+ // v2 <= v0 <= v1.
+ var tmp = v0;
+ v0 = v2;
+ v2 = v1;
+ v1 = tmp;
+ } else {
+ // v0 <= v1 && v0 < v2
+ var c12 = %_CallFunction(receiver, v1, v2, comparefn);
+ if (c12 > 0) {
+ // v0 <= v2 < v1
+ var tmp = v1;
+ v1 = v2;
+ v2 = tmp;
+ }
+ }
+ // v0 <= v1 <= v2
+ a[from] = v0;
+ a[to - 1] = v2;
+ var pivot = v1;
+ var low_end = from + 1; // Upper bound of elements lower than pivot.
+ var high_start = to - 1; // Lower bound of elements greater than pivot.
+ a[third_index] = a[low_end];
+ a[low_end] = pivot;
+
+ // From low_end to i are elements equal to pivot.
+ // From i to high_start are elements that haven't been compared yet.
+ partition: for (var i = low_end + 1; i < high_start; i++) {
+ var element = a[i];
+ var order = %_CallFunction(receiver, element, pivot, comparefn);
if (order < 0) {
- element = a[i];
a[i] = a[low_end];
a[low_end] = element;
low_end++;
+ } else if (order > 0) {
+ do {
+ high_start--;
+ if (high_start == i) break partition;
+ var top_elem = a[high_start];
+ order = %_CallFunction(receiver, top_elem, pivot, comparefn);
+ } while (order > 0);
+ a[i] = a[high_start];
+ a[high_start] = element;
+ if (order < 0) {
+ element = a[i];
+ a[i] = a[low_end];
+ a[low_end] = element;
+ low_end++;
+ }
}
}
+ if (to - high_start < low_end - from) {
+ QuickSort(a, high_start, to);
+ to = low_end;
+ } else {
+ QuickSort(a, from, low_end);
+ from = high_start;
+ }
}
- QuickSort(a, from, low_end);
- QuickSort(a, high_start, to);
};
// Copy elements in the range 0..length from obj's prototype chain