BLI: generally improve C++ data structures

The main focus here was to improve the docs significantly. Furthermore,
I reimplemented `Set`, `Map` and `VectorSet`. They are now (usually)
faster, simpler and more customizable. I also rewrote `Stack` to make
it more efficient by avoiding unnecessary copies.

Thanks to everyone who helped with constructive feedback.

Approved by brecht and sybren.

Differential Revision: https://developer.blender.org/D7931

1 files changed, 5 insertions, 6 deletions

diff --git a/source/blender/blenlib/intern/math_bits_inline.c b/source/blender/blenlib/intern/math_bits_inline.c
index a6883c2aaba..8f8f257f1e7 100644
--- a/source/blender/blenlib/intern/math_bits_inline.c
+++ b/source/blender/blenlib/intern/math_bits_inline.c
@@ -77,8 +77,7 @@ MINLINE int bitscan_reverse_i(int a)
 MINLINE unsigned int bitscan_reverse_clear_uint(unsigned int *a)
 {
   unsigned int i = bitscan_reverse_uint(*a);
-  /* TODO(sergey): This could probably be optimized. */
-  *a &= ~(1 << (sizeof(unsigned int) * 8 - i - 1));
+  *a &= ~(0x80000000 >> i);
   return i;
 }
 
@@ -97,10 +96,10 @@ MINLINE unsigned int highest_order_bit_uint(unsigned int n)
 
 MINLINE unsigned short highest_order_bit_s(unsigned short n)
 {
-  n |= (n >> 1);
-  n |= (n >> 2);
-  n |= (n >> 4);
-  n |= (n >> 8);
+  n |= (unsigned short)(n >> 1);
+  n |= (unsigned short)(n >> 2);
+  n |= (unsigned short)(n >> 4);
+  n |= (unsigned short)(n >> 8);
   return (unsigned short)(n - (n >> 1));
 }