glibc/sysdeps/aarch64/fpu/hypotf_sve.c
Joe Ramsay 157f89fa3d aarch64/fpu: Add vector variants of hypot
Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
2024-05-16 14:34:43 +01:00

49 lines
1.7 KiB
C

/* Single-precision vector (SVE) hypot function
Copyright (C) 2024 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library 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.
The GNU C Library 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 the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include "sv_math.h"
#define TinyBound 0x0c800000 /* asuint (0x1p-102). */
#define Thres 0x73000000 /* 0x70000000 - TinyBound. */
static svfloat32_t NOINLINE
special_case (svfloat32_t sqsum, svfloat32_t x, svfloat32_t y, svbool_t pg,
svbool_t special)
{
return sv_call2_f32 (hypotf, x, y, svsqrt_x (pg, sqsum), special);
}
/* SVE implementation of single-precision hypot.
Maximum error observed is 1.21 ULP:
_ZGVsMxvv_hypotf (0x1.6a213cp-19, -0x1.32b982p-26) got 0x1.6a2346p-19
want 0x1.6a2344p-19. */
svfloat32_t SV_NAME_F2 (hypot) (svfloat32_t x, svfloat32_t y,
const svbool_t pg)
{
svfloat32_t sqsum = svmla_x (pg, svmul_x (pg, x, x), y, y);
svbool_t special = svcmpge (
pg, svsub_x (pg, svreinterpret_u32 (sqsum), TinyBound), Thres);
if (__glibc_unlikely (svptest_any (pg, special)))
return special_case (sqsum, x, y, pg, special);
return svsqrt_x (pg, sqsum);
}