cosmopolitan/libc/tinymath/lrint.c
Justine Tunney c3440d040c
Make improvements
- More timspec_*() and timeval_*() APIs have been introduced.
- The copyfd() function is now simplified thanks to POSIX rules.
- More Cosmo-specific APIs have been moved behind the COSMO define.
- The setitimer() polyfill for Windows NT is now much higher quality.
- Fixed build error for MODE=aarch64 due to -mstringop-strategy=loop.
- This change introduces `make MODE=nox87 toolchain` which makes it
  possible to build programs using your cosmocc toolchain that don't
  have legacy fpu instructions. This is useful, for example, if you
  want to have a ~22kb tinier blink virtual machine.
2023-06-15 14:50:53 -07:00

52 lines
2.6 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2023 Justine Alexandra Roberts Tunney │
│ │
│ Permission to use, copy, modify, and/or distribute this software for │
│ any purpose with or without fee is hereby granted, provided that the │
│ above copyright notice and this permission notice appear in all copies. │
│ │
│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL │
│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED │
│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE │
│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL │
│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR │
│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER │
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │
│ PERFORMANCE OF THIS SOFTWARE. │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/math.h"
/**
* Rounds to integer in current rounding mode.
*
* The floating-point exception `FE_INEXACT` is raised if the result is
* different from the input.
*/
long lrint(double x) {
long i;
#ifdef __x86_64__
asm("cvtsd2si\t%1,%0" : "=r"(i) : "x"(x));
#elif defined(__aarch64__)
asm("frintx\t%d1,%d1\n\t"
"fcvtzs\t%x0,%d1"
: "=r"(i), "+w"(x));
#elif defined(__powerpc64__) && defined(_ARCH_PWR5X)
asm("fctid\t%0,%1" : "=d"(i) : "d"(x));
#else
i = rint(x);
#endif /* __x86_64__ */
return i;
}
#if __SIZEOF_LONG__ == __SIZEOF_LONG_LONG__
__weak_reference(lrint, llrint);
#endif
#if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024
__weak_reference(lrint, lrintl);
#if __SIZEOF_LONG__ == __SIZEOF_LONG_LONG__
__weak_reference(lrint, llrintl);
#endif
#endif