Files
RedBear-OS/recipes/tools/nano/source/lib/signbitd.c
T
vasilito 7686729069 drm: implement syncobj and fence for VIRGL/VirtIO driver
Extract protocol-agnostic FenceTimeline from Intel to shared
src/drivers/fence.rs — atomic-based fence tracking suitable
for Intel, VIRGL, and AMD drivers.

Extract protocol-agnostic SyncobjManager from Intel to shared
src/drivers/syncobj.rs — syncobj create/destroy/signal/reset/
wait/query and sync_file fd export/import.

Wire both into VirtioDriver:
- Add FenceTimeline + SyncobjManager fields
- Implement all 5 GpuDriver syncobj trait methods
  (create, destroy, wait, export_fd, import_fd)
- Track fence seqnos in virgl_submit_3d (allocate
  before submit, signal after completion)

Intel fence.rs and syncobj.rs converted to thin re-export
modules pointing at shared sources — no behavioral change
for Intel driver.

This gives Mesa VIRGL userspace the standard DRM syncobj
API for GPU/compositor synchronization.
2026-06-02 14:33:28 +03:00

65 lines
2.1 KiB
C

/* signbit() macro: Determine the sign bit of a floating-point number.
Copyright (C) 2007-2023 Free Software Foundation, Inc.
This file is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as
published by the Free Software Foundation; either version 2.1 of the
License, or (at your option) any later version.
This file is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>. */
#include <config.h>
/* Specification. */
#include <math.h>
#include <string.h>
#include "isnand-nolibm.h"
#include "float+.h"
#ifdef gl_signbitd_OPTIMIZED_MACRO
# undef gl_signbitd
#endif
int
gl_signbitd (double arg)
{
#if defined DBL_SIGNBIT_WORD && defined DBL_SIGNBIT_BIT
/* The use of a union to extract the bits of the representation of a
'long double' is safe in practice, despite of the "aliasing rules" of
C99, because the GCC docs say
"Even with '-fstrict-aliasing', type-punning is allowed, provided the
memory is accessed through the union type."
and similarly for other compilers. */
# define NWORDS \
((sizeof (double) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
union { double value; unsigned int word[NWORDS]; } m;
m.value = arg;
return (m.word[DBL_SIGNBIT_WORD] >> DBL_SIGNBIT_BIT) & 1;
#elif HAVE_COPYSIGN_IN_LIBC
return copysign (1.0, arg) < 0;
#else
/* This does not do the right thing for NaN, but this is irrelevant for
most use cases. */
if (isnand (arg))
return 0;
if (arg < 0.0)
return 1;
else if (arg == 0.0)
{
/* Distinguish 0.0 and -0.0. */
static double plus_zero = 0.0;
double arg_mem = arg;
return (memcmp (&plus_zero, &arg_mem, SIZEOF_DBL) != 0);
}
else
return 0;
#endif
}