Files
test2/source/blender/blenlib/intern/math_bits_inline.c
Campbell Barton e955c94ed3 License Headers: Set copyright to "Blender Authors", add AUTHORS
Listing the "Blender Foundation" as copyright holder implied the Blender
Foundation holds copyright to files which may include work from many
developers.

While keeping copyright on headers makes sense for isolated libraries,
Blender's own code may be refactored or moved between files in a way
that makes the per file copyright holders less meaningful.

Copyright references to the "Blender Foundation" have been replaced with
"Blender Authors", with the exception of `./extern/` since these this
contains libraries which are more isolated, any changed to license
headers there can be handled on a case-by-case basis.

Some directories in `./intern/` have also been excluded:

- `./intern/cycles/` it's own `AUTHORS` file is planned.
- `./intern/opensubdiv/`.

An "AUTHORS" file has been added, using the chromium projects authors
file as a template.

Design task: #110784

Ref !110783.
2023-08-16 00:20:26 +10:00

173 lines
3.1 KiB
C

/* SPDX-FileCopyrightText: 2023 Blender Authors
*
* SPDX-License-Identifier: GPL-2.0-or-later */
/** \file
* \ingroup bli
*/
#ifndef __MATH_BITS_INLINE_C__
#define __MATH_BITS_INLINE_C__
#ifdef _MSC_VER
# include <intrin.h>
#endif
#include "BLI_math_bits.h"
MINLINE unsigned int bitscan_forward_uint(unsigned int a)
{
BLI_assert(a != 0);
#ifdef _MSC_VER
unsigned long ctz;
_BitScanForward(&ctz, a);
return ctz;
#else
return (unsigned int)__builtin_ctz(a);
#endif
}
MINLINE unsigned int bitscan_forward_uint64(unsigned long long a)
{
BLI_assert(a != 0);
#ifdef _MSC_VER
unsigned long ctz;
_BitScanForward64(&ctz, a);
return ctz;
#else
return (unsigned int)__builtin_ctzll(a);
#endif
}
MINLINE int bitscan_forward_i(int a)
{
return (int)bitscan_forward_uint((unsigned int)a);
}
MINLINE unsigned int bitscan_forward_clear_uint(unsigned int *a)
{
unsigned int i = bitscan_forward_uint(*a);
*a &= (*a) - 1;
return i;
}
MINLINE int bitscan_forward_clear_i(int *a)
{
return (int)bitscan_forward_clear_uint((unsigned int *)a);
}
MINLINE unsigned int bitscan_reverse_uint(unsigned int a)
{
BLI_assert(a != 0);
#ifdef _MSC_VER
unsigned long clz;
_BitScanReverse(&clz, a);
return 31 - clz;
#else
return (unsigned int)__builtin_clz(a);
#endif
}
MINLINE unsigned int bitscan_reverse_uint64(unsigned long long a)
{
BLI_assert(a != 0);
#ifdef _MSC_VER
unsigned long clz;
_BitScanReverse64(&clz, a);
return 31 - clz;
#else
return (unsigned int)__builtin_clzll(a);
#endif
}
MINLINE int bitscan_reverse_i(int a)
{
return (int)bitscan_reverse_uint((unsigned int)a);
}
MINLINE unsigned int bitscan_reverse_clear_uint(unsigned int *a)
{
unsigned int i = bitscan_reverse_uint(*a);
*a &= ~(0x80000000 >> i);
return i;
}
MINLINE int bitscan_reverse_clear_i(int *a)
{
return (int)bitscan_reverse_clear_uint((unsigned int *)a);
}
MINLINE unsigned int highest_order_bit_uint(unsigned int n)
{
if (n == 0) {
return 0;
}
return 1 << (sizeof(unsigned int) * 8 - bitscan_reverse_uint(n));
}
MINLINE unsigned short highest_order_bit_s(unsigned short n)
{
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));
}
#ifndef __GNUC__
MINLINE int count_bits_i(unsigned int i)
{
/* variable-precision SWAR algorithm. */
i = i - ((i >> 1) & 0x55555555);
i = (i & 0x33333333) + ((i >> 2) & 0x33333333);
return (((i + (i >> 4)) & 0x0F0F0F0F) * 0x01010101) >> 24;
}
#endif
MINLINE int float_as_int(float f)
{
union {
int i;
float f;
} u;
u.f = f;
return u.i;
}
MINLINE unsigned int float_as_uint(float f)
{
union {
unsigned int i;
float f;
} u;
u.f = f;
return u.i;
}
MINLINE float int_as_float(int i)
{
union {
int i;
float f;
} u;
u.i = i;
return u.f;
}
MINLINE float uint_as_float(unsigned int i)
{
union {
unsigned int i;
float f;
} u;
u.i = i;
return u.f;
}
MINLINE float xor_fl(float x, int y)
{
return int_as_float(float_as_int(x) ^ y);
}
#endif /* __MATH_BITS_INLINE_C__ */