# HG changeset patch
# User Rik <rik@octave.org>
# Date 1629139540 25200
# Node ID 06bf5aca68bb74932e9ad3bf092c71e014a2666a
# Parent  65c6095040360d5bb73058097b9a867c1e72d581
Improve performance of sort along dimensions > 1 (bug #60928).

* Array.cc (sort (dim, mode), sort (&sidx, dim, mode)):
Replace calculation of offset using while loop with division and multiplication
of integers.

diff -r 65c609504036 -r 06bf5aca68bb liboctave/array/Array.cc
--- a/liboctave/array/Array.cc	Mon Aug 16 19:16:58 2021 +0200
+++ b/liboctave/array/Array.cc	Mon Aug 16 11:45:40 2021 -0700
@@ -1830,15 +1830,8 @@
       for (octave_idx_type j = 0; j < iter; j++)
         {
           octave_idx_type offset = j;
-          octave_idx_type offset2 = 0;
-
-          while (offset >= stride)
-            {
-              offset -= stride;
-              offset2++;
-            }
-
-          offset += offset2 * stride * ns;
+          octave_idx_type n_strides = j / stride;
+          offset += n_strides * stride * (ns - 1);
 
           // gather and partition out NaNs.
           // FIXME: impact on integer types noticeable?
@@ -1964,15 +1957,8 @@
       for (octave_idx_type j = 0; j < iter; j++)
         {
           octave_idx_type offset = j;
-          octave_idx_type offset2 = 0;
-
-          while (offset >= stride)
-            {
-              offset -= stride;
-              offset2++;
-            }
-
-          offset += offset2 * stride * ns;
+          octave_idx_type n_strides = j / stride;
+          offset += n_strides * stride * (ns - 1);
 
           // gather and partition out NaNs.
           // FIXME: impact on integer types noticeable?