[5/6] aarch64: Add vector implementations of log1p routines
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Commit Message
May discard sign of zero.
---
Thanks,
Joe
math/auto-libm-test-in | 2 +-
math/auto-libm-test-out-log1p | 50 +++----
sysdeps/aarch64/fpu/Makefile | 1 +
sysdeps/aarch64/fpu/Versions | 4 +
sysdeps/aarch64/fpu/bits/math-vector.h | 4 +
sysdeps/aarch64/fpu/log1p_advsimd.c | 129 ++++++++++++++++++
sysdeps/aarch64/fpu/log1p_sve.c | 118 ++++++++++++++++
sysdeps/aarch64/fpu/log1pf_advsimd.c | 128 +++++++++++++++++
sysdeps/aarch64/fpu/log1pf_sve.c | 100 ++++++++++++++
.../fpu/test-double-advsimd-wrappers.c | 1 +
.../aarch64/fpu/test-double-sve-wrappers.c | 1 +
.../aarch64/fpu/test-float-advsimd-wrappers.c | 1 +
sysdeps/aarch64/fpu/test-float-sve-wrappers.c | 1 +
sysdeps/aarch64/libm-test-ulps | 8 ++
.../unix/sysv/linux/aarch64/libmvec.abilist | 4 +
15 files changed, 526 insertions(+), 26 deletions(-)
create mode 100644 sysdeps/aarch64/fpu/log1p_advsimd.c
create mode 100644 sysdeps/aarch64/fpu/log1p_sve.c
create mode 100644 sysdeps/aarch64/fpu/log1pf_advsimd.c
create mode 100644 sysdeps/aarch64/fpu/log1pf_sve.c
Comments
The 11/03/2023 12:12, Joe Ramsay wrote:
> May discard sign of zero.
> ---
i reviewed the generic changes: ignoring sign of zero for
log1p mathvec tests is OK, this can be committed.
Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
> Thanks,
> Joe
> math/auto-libm-test-in | 2 +-
> math/auto-libm-test-out-log1p | 50 +++----
> sysdeps/aarch64/fpu/Makefile | 1 +
> sysdeps/aarch64/fpu/Versions | 4 +
> sysdeps/aarch64/fpu/bits/math-vector.h | 4 +
> sysdeps/aarch64/fpu/log1p_advsimd.c | 129 ++++++++++++++++++
> sysdeps/aarch64/fpu/log1p_sve.c | 118 ++++++++++++++++
> sysdeps/aarch64/fpu/log1pf_advsimd.c | 128 +++++++++++++++++
> sysdeps/aarch64/fpu/log1pf_sve.c | 100 ++++++++++++++
> .../fpu/test-double-advsimd-wrappers.c | 1 +
> .../aarch64/fpu/test-double-sve-wrappers.c | 1 +
> .../aarch64/fpu/test-float-advsimd-wrappers.c | 1 +
> sysdeps/aarch64/fpu/test-float-sve-wrappers.c | 1 +
> sysdeps/aarch64/libm-test-ulps | 8 ++
> .../unix/sysv/linux/aarch64/libmvec.abilist | 4 +
> 15 files changed, 526 insertions(+), 26 deletions(-)
> create mode 100644 sysdeps/aarch64/fpu/log1p_advsimd.c
> create mode 100644 sysdeps/aarch64/fpu/log1p_sve.c
> create mode 100644 sysdeps/aarch64/fpu/log1pf_advsimd.c
> create mode 100644 sysdeps/aarch64/fpu/log1pf_sve.c
>
> diff --git a/math/auto-libm-test-in b/math/auto-libm-test-in
> index 70892503d6..a8d6674c98 100644
> --- a/math/auto-libm-test-in
> +++ b/math/auto-libm-test-in
> @@ -6577,7 +6577,7 @@ log10 0xf.bf1b2p-4
> log10 0x1.6b5f7ap+96
>
> log1p 0
> -log1p -0
> +log1p -0 no-mathvec
> log1p e-1
> log1p -0.25
> log1p -0.875
> diff --git a/math/auto-libm-test-out-log1p b/math/auto-libm-test-out-log1p
> index f7d3b35e6d..f83241f51a 100644
> --- a/math/auto-libm-test-out-log1p
> +++ b/math/auto-libm-test-out-log1p
> @@ -23,31 +23,31 @@ log1p 0
> = log1p tonearest ibm128 0x0p+0 : 0x0p+0 : inexact-ok
> = log1p towardzero ibm128 0x0p+0 : 0x0p+0 : inexact-ok
> = log1p upward ibm128 0x0p+0 : 0x0p+0 : inexact-ok
> -log1p -0
> -= log1p downward binary32 -0x0p+0 : -0x0p+0 : inexact-ok
> -= log1p tonearest binary32 -0x0p+0 : -0x0p+0 : inexact-ok
> -= log1p towardzero binary32 -0x0p+0 : -0x0p+0 : inexact-ok
> -= log1p upward binary32 -0x0p+0 : -0x0p+0 : inexact-ok
> -= log1p downward binary64 -0x0p+0 : -0x0p+0 : inexact-ok
> -= log1p tonearest binary64 -0x0p+0 : -0x0p+0 : inexact-ok
> -= log1p towardzero binary64 -0x0p+0 : -0x0p+0 : inexact-ok
> -= log1p upward binary64 -0x0p+0 : -0x0p+0 : inexact-ok
> -= log1p downward intel96 -0x0p+0 : -0x0p+0 : inexact-ok
> -= log1p tonearest intel96 -0x0p+0 : -0x0p+0 : inexact-ok
> -= log1p towardzero intel96 -0x0p+0 : -0x0p+0 : inexact-ok
> -= log1p upward intel96 -0x0p+0 : -0x0p+0 : inexact-ok
> -= log1p downward m68k96 -0x0p+0 : -0x0p+0 : inexact-ok
> -= log1p tonearest m68k96 -0x0p+0 : -0x0p+0 : inexact-ok
> -= log1p towardzero m68k96 -0x0p+0 : -0x0p+0 : inexact-ok
> -= log1p upward m68k96 -0x0p+0 : -0x0p+0 : inexact-ok
> -= log1p downward binary128 -0x0p+0 : -0x0p+0 : inexact-ok
> -= log1p tonearest binary128 -0x0p+0 : -0x0p+0 : inexact-ok
> -= log1p towardzero binary128 -0x0p+0 : -0x0p+0 : inexact-ok
> -= log1p upward binary128 -0x0p+0 : -0x0p+0 : inexact-ok
> -= log1p downward ibm128 -0x0p+0 : -0x0p+0 : inexact-ok
> -= log1p tonearest ibm128 -0x0p+0 : -0x0p+0 : inexact-ok
> -= log1p towardzero ibm128 -0x0p+0 : -0x0p+0 : inexact-ok
> -= log1p upward ibm128 -0x0p+0 : -0x0p+0 : inexact-ok
> +log1p -0 no-mathvec
> += log1p downward binary32 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
> += log1p tonearest binary32 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
> += log1p towardzero binary32 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
> += log1p upward binary32 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
> += log1p downward binary64 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
> += log1p tonearest binary64 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
> += log1p towardzero binary64 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
> += log1p upward binary64 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
> += log1p downward intel96 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
> += log1p tonearest intel96 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
> += log1p towardzero intel96 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
> += log1p upward intel96 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
> += log1p downward m68k96 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
> += log1p tonearest m68k96 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
> += log1p towardzero m68k96 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
> += log1p upward m68k96 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
> += log1p downward binary128 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
> += log1p tonearest binary128 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
> += log1p towardzero binary128 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
> += log1p upward binary128 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
> += log1p downward ibm128 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
> += log1p tonearest ibm128 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
> += log1p towardzero ibm128 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
> += log1p upward ibm128 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
> log1p e-1
> = log1p downward binary32 0x1.b7e152p+0 : 0x1p+0 : inexact-ok
> = log1p tonearest binary32 0x1.b7e152p+0 : 0x1p+0 : inexact-ok
> diff --git a/sysdeps/aarch64/fpu/Makefile b/sysdeps/aarch64/fpu/Makefile
> index 364efbeac1..c77c709edd 100644
> --- a/sysdeps/aarch64/fpu/Makefile
> +++ b/sysdeps/aarch64/fpu/Makefile
> @@ -8,6 +8,7 @@ libmvec-supported-funcs = acos \
> exp2 \
> log \
> log10 \
> + log1p \
> log2 \
> sin \
> tan
> diff --git a/sysdeps/aarch64/fpu/Versions b/sysdeps/aarch64/fpu/Versions
> index 99492b3d33..2543649fbe 100644
> --- a/sysdeps/aarch64/fpu/Versions
> +++ b/sysdeps/aarch64/fpu/Versions
> @@ -46,6 +46,10 @@ libmvec {
> _ZGVnN2v_log10;
> _ZGVsMxv_log10f;
> _ZGVsMxv_log10;
> + _ZGVnN4v_log1pf;
> + _ZGVnN2v_log1p;
> + _ZGVsMxv_log1pf;
> + _ZGVsMxv_log1p;
> _ZGVnN4v_log2f;
> _ZGVnN2v_log2;
> _ZGVsMxv_log2f;
> diff --git a/sysdeps/aarch64/fpu/bits/math-vector.h b/sysdeps/aarch64/fpu/bits/math-vector.h
> index 7666c09083..51915cef22 100644
> --- a/sysdeps/aarch64/fpu/bits/math-vector.h
> +++ b/sysdeps/aarch64/fpu/bits/math-vector.h
> @@ -59,6 +59,7 @@ __vpcs __f32x4_t _ZGVnN4v_exp10f (__f32x4_t);
> __vpcs __f32x4_t _ZGVnN4v_exp2f (__f32x4_t);
> __vpcs __f32x4_t _ZGVnN4v_logf (__f32x4_t);
> __vpcs __f32x4_t _ZGVnN4v_log10f (__f32x4_t);
> +__vpcs __f32x4_t _ZGVnN4v_log1pf (__f32x4_t);
> __vpcs __f32x4_t _ZGVnN4v_log2f (__f32x4_t);
> __vpcs __f32x4_t _ZGVnN4v_sinf (__f32x4_t);
> __vpcs __f32x4_t _ZGVnN4v_tanf (__f32x4_t);
> @@ -73,6 +74,7 @@ __vpcs __f64x2_t _ZGVnN2v_exp10 (__f64x2_t);
> __vpcs __f64x2_t _ZGVnN2v_exp2 (__f64x2_t);
> __vpcs __f64x2_t _ZGVnN2v_log (__f64x2_t);
> __vpcs __f64x2_t _ZGVnN2v_log10 (__f64x2_t);
> +__vpcs __f64x2_t _ZGVnN2v_log1p (__f64x2_t);
> __vpcs __f64x2_t _ZGVnN2v_log2 (__f64x2_t);
> __vpcs __f64x2_t _ZGVnN2v_sin (__f64x2_t);
> __vpcs __f64x2_t _ZGVnN2v_tan (__f64x2_t);
> @@ -92,6 +94,7 @@ __sv_f32_t _ZGVsMxv_exp10f (__sv_f32_t, __sv_bool_t);
> __sv_f32_t _ZGVsMxv_exp2f (__sv_f32_t, __sv_bool_t);
> __sv_f32_t _ZGVsMxv_logf (__sv_f32_t, __sv_bool_t);
> __sv_f32_t _ZGVsMxv_log10f (__sv_f32_t, __sv_bool_t);
> +__sv_f32_t _ZGVsMxv_log1pf (__sv_f32_t, __sv_bool_t);
> __sv_f32_t _ZGVsMxv_log2f (__sv_f32_t, __sv_bool_t);
> __sv_f32_t _ZGVsMxv_sinf (__sv_f32_t, __sv_bool_t);
> __sv_f32_t _ZGVsMxv_tanf (__sv_f32_t, __sv_bool_t);
> @@ -106,6 +109,7 @@ __sv_f64_t _ZGVsMxv_exp10 (__sv_f64_t, __sv_bool_t);
> __sv_f64_t _ZGVsMxv_exp2 (__sv_f64_t, __sv_bool_t);
> __sv_f64_t _ZGVsMxv_log (__sv_f64_t, __sv_bool_t);
> __sv_f64_t _ZGVsMxv_log10 (__sv_f64_t, __sv_bool_t);
> +__sv_f64_t _ZGVsMxv_log1p (__sv_f64_t, __sv_bool_t);
> __sv_f64_t _ZGVsMxv_log2 (__sv_f64_t, __sv_bool_t);
> __sv_f64_t _ZGVsMxv_sin (__sv_f64_t, __sv_bool_t);
> __sv_f64_t _ZGVsMxv_tan (__sv_f64_t, __sv_bool_t);
> diff --git a/sysdeps/aarch64/fpu/log1p_advsimd.c b/sysdeps/aarch64/fpu/log1p_advsimd.c
> new file mode 100644
> index 0000000000..a117e1b6dc
> --- /dev/null
> +++ b/sysdeps/aarch64/fpu/log1p_advsimd.c
> @@ -0,0 +1,129 @@
> +/* Double-precision AdvSIMD log1p
> +
> + Copyright (C) 2023 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 "v_math.h"
> +#include "poly_advsimd_f64.h"
> +
> +const static struct data
> +{
> + float64x2_t poly[19], ln2[2];
> + uint64x2_t hf_rt2_top, one_m_hf_rt2_top, umask, inf, minus_one;
> + int64x2_t one_top;
> +} data = {
> + /* Generated using Remez, deg=20, in [sqrt(2)/2-1, sqrt(2)-1]. */
> + .poly = { V2 (-0x1.ffffffffffffbp-2), V2 (0x1.55555555551a9p-2),
> + V2 (-0x1.00000000008e3p-2), V2 (0x1.9999999a32797p-3),
> + V2 (-0x1.555555552fecfp-3), V2 (0x1.249248e071e5ap-3),
> + V2 (-0x1.ffffff8bf8482p-4), V2 (0x1.c71c8f07da57ap-4),
> + V2 (-0x1.9999ca4ccb617p-4), V2 (0x1.7459ad2e1dfa3p-4),
> + V2 (-0x1.554d2680a3ff2p-4), V2 (0x1.3b4c54d487455p-4),
> + V2 (-0x1.2548a9ffe80e6p-4), V2 (0x1.0f389a24b2e07p-4),
> + V2 (-0x1.eee4db15db335p-5), V2 (0x1.e95b494d4a5ddp-5),
> + V2 (-0x1.15fdf07cb7c73p-4), V2 (0x1.0310b70800fcfp-4),
> + V2 (-0x1.cfa7385bdb37ep-6) },
> + .ln2 = { V2 (0x1.62e42fefa3800p-1), V2 (0x1.ef35793c76730p-45) },
> + /* top32(asuint64(sqrt(2)/2)) << 32. */
> + .hf_rt2_top = V2 (0x3fe6a09e00000000),
> + /* (top32(asuint64(1)) - top32(asuint64(sqrt(2)/2))) << 32. */
> + .one_m_hf_rt2_top = V2 (0x00095f6200000000),
> + .umask = V2 (0x000fffff00000000),
> + .one_top = V2 (0x3ff),
> + .inf = V2 (0x7ff0000000000000),
> + .minus_one = V2 (0xbff0000000000000)
> +};
> +
> +#define BottomMask v_u64 (0xffffffff)
> +
> +static float64x2_t VPCS_ATTR NOINLINE
> +special_case (float64x2_t x, float64x2_t y, uint64x2_t special)
> +{
> + return v_call_f64 (log1p, x, y, special);
> +}
> +
> +/* Vector log1p approximation using polynomial on reduced interval. Routine is
> + a modification of the algorithm used in scalar log1p, with no shortcut for
> + k=0 and no narrowing for f and k. Maximum observed error is 2.45 ULP:
> + _ZGVnN2v_log1p(0x1.658f7035c4014p+11) got 0x1.fd61d0727429dp+2
> + want 0x1.fd61d0727429fp+2 . */
> +VPCS_ATTR float64x2_t V_NAME_D1 (log1p) (float64x2_t x)
> +{
> + const struct data *d = ptr_barrier (&data);
> + uint64x2_t ix = vreinterpretq_u64_f64 (x);
> + uint64x2_t ia = vreinterpretq_u64_f64 (vabsq_f64 (x));
> + uint64x2_t special = vcgeq_u64 (ia, d->inf);
> +
> +#if WANT_SIMD_EXCEPT
> + special = vorrq_u64 (special,
> + vcgeq_u64 (ix, vreinterpretq_u64_f64 (v_f64 (-1))));
> + if (__glibc_unlikely (v_any_u64 (special)))
> + x = v_zerofy_f64 (x, special);
> +#else
> + special = vorrq_u64 (special, vcleq_f64 (x, v_f64 (-1)));
> +#endif
> +
> + /* With x + 1 = t * 2^k (where t = f + 1 and k is chosen such that f
> + is in [sqrt(2)/2, sqrt(2)]):
> + log1p(x) = k*log(2) + log1p(f).
> +
> + f may not be representable exactly, so we need a correction term:
> + let m = round(1 + x), c = (1 + x) - m.
> + c << m: at very small x, log1p(x) ~ x, hence:
> + log(1+x) - log(m) ~ c/m.
> +
> + We therefore calculate log1p(x) by k*log2 + log1p(f) + c/m. */
> +
> + /* Obtain correctly scaled k by manipulation in the exponent.
> + The scalar algorithm casts down to 32-bit at this point to calculate k and
> + u_red. We stay in double-width to obtain f and k, using the same constants
> + as the scalar algorithm but shifted left by 32. */
> + float64x2_t m = vaddq_f64 (x, v_f64 (1));
> + uint64x2_t mi = vreinterpretq_u64_f64 (m);
> + uint64x2_t u = vaddq_u64 (mi, d->one_m_hf_rt2_top);
> +
> + int64x2_t ki
> + = vsubq_s64 (vreinterpretq_s64_u64 (vshrq_n_u64 (u, 52)), d->one_top);
> + float64x2_t k = vcvtq_f64_s64 (ki);
> +
> + /* Reduce x to f in [sqrt(2)/2, sqrt(2)]. */
> + uint64x2_t utop = vaddq_u64 (vandq_u64 (u, d->umask), d->hf_rt2_top);
> + uint64x2_t u_red = vorrq_u64 (utop, vandq_u64 (mi, BottomMask));
> + float64x2_t f = vsubq_f64 (vreinterpretq_f64_u64 (u_red), v_f64 (1));
> +
> + /* Correction term c/m. */
> + float64x2_t cm = vdivq_f64 (vsubq_f64 (x, vsubq_f64 (m, v_f64 (1))), m);
> +
> + /* Approximate log1p(x) on the reduced input using a polynomial. Because
> + log1p(0)=0 we choose an approximation of the form:
> + x + C0*x^2 + C1*x^3 + C2x^4 + ...
> + Hence approximation has the form f + f^2 * P(f)
> + where P(x) = C0 + C1*x + C2x^2 + ...
> + Assembling this all correctly is dealt with at the final step. */
> + float64x2_t f2 = vmulq_f64 (f, f);
> + float64x2_t p = v_pw_horner_18_f64 (f, f2, d->poly);
> +
> + float64x2_t ylo = vfmaq_f64 (cm, k, d->ln2[1]);
> + float64x2_t yhi = vfmaq_f64 (f, k, d->ln2[0]);
> + float64x2_t y = vaddq_f64 (ylo, yhi);
> +
> + if (__glibc_unlikely (v_any_u64 (special)))
> + return special_case (vreinterpretq_f64_u64 (ix), vfmaq_f64 (y, f2, p),
> + special);
> +
> + return vfmaq_f64 (y, f2, p);
> +}
> diff --git a/sysdeps/aarch64/fpu/log1p_sve.c b/sysdeps/aarch64/fpu/log1p_sve.c
> new file mode 100644
> index 0000000000..169156748d
> --- /dev/null
> +++ b/sysdeps/aarch64/fpu/log1p_sve.c
> @@ -0,0 +1,118 @@
> +/* Double-precision SVE log1p
> +
> + Copyright (C) 2023 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"
> +#include "poly_sve_f64.h"
> +
> +static const struct data
> +{
> + double poly[19];
> + double ln2_hi, ln2_lo;
> + uint64_t hfrt2_top, onemhfrt2_top, inf, mone;
> +} data = {
> + /* Generated using Remez in [ sqrt(2)/2 - 1, sqrt(2) - 1]. Order 20
> + polynomial, however first 2 coefficients are 0 and 1 so are not stored. */
> + .poly = { -0x1.ffffffffffffbp-2, 0x1.55555555551a9p-2, -0x1.00000000008e3p-2,
> + 0x1.9999999a32797p-3, -0x1.555555552fecfp-3, 0x1.249248e071e5ap-3,
> + -0x1.ffffff8bf8482p-4, 0x1.c71c8f07da57ap-4, -0x1.9999ca4ccb617p-4,
> + 0x1.7459ad2e1dfa3p-4, -0x1.554d2680a3ff2p-4, 0x1.3b4c54d487455p-4,
> + -0x1.2548a9ffe80e6p-4, 0x1.0f389a24b2e07p-4, -0x1.eee4db15db335p-5,
> + 0x1.e95b494d4a5ddp-5, -0x1.15fdf07cb7c73p-4, 0x1.0310b70800fcfp-4,
> + -0x1.cfa7385bdb37ep-6, },
> + .ln2_hi = 0x1.62e42fefa3800p-1,
> + .ln2_lo = 0x1.ef35793c76730p-45,
> + /* top32(asuint64(sqrt(2)/2)) << 32. */
> + .hfrt2_top = 0x3fe6a09e00000000,
> + /* (top32(asuint64(1)) - top32(asuint64(sqrt(2)/2))) << 32. */
> + .onemhfrt2_top = 0x00095f6200000000,
> + .inf = 0x7ff0000000000000,
> + .mone = 0xbff0000000000000,
> +};
> +
> +#define AbsMask 0x7fffffffffffffff
> +#define BottomMask 0xffffffff
> +
> +static svfloat64_t NOINLINE
> +special_case (svbool_t special, svfloat64_t x, svfloat64_t y)
> +{
> + return sv_call_f64 (log1p, x, y, special);
> +}
> +
> +/* Vector approximation for log1p using polynomial on reduced interval. Maximum
> + observed error is 2.46 ULP:
> + _ZGVsMxv_log1p(0x1.654a1307242a4p+11) got 0x1.fd5565fb590f4p+2
> + want 0x1.fd5565fb590f6p+2. */
> +svfloat64_t SV_NAME_D1 (log1p) (svfloat64_t x, svbool_t pg)
> +{
> + const struct data *d = ptr_barrier (&data);
> + svuint64_t ix = svreinterpret_u64 (x);
> + svuint64_t ax = svand_x (pg, ix, AbsMask);
> + svbool_t special
> + = svorr_z (pg, svcmpge (pg, ax, d->inf), svcmpge (pg, ix, d->mone));
> +
> + /* With x + 1 = t * 2^k (where t = f + 1 and k is chosen such that f
> + is in [sqrt(2)/2, sqrt(2)]):
> + log1p(x) = k*log(2) + log1p(f).
> +
> + f may not be representable exactly, so we need a correction term:
> + let m = round(1 + x), c = (1 + x) - m.
> + c << m: at very small x, log1p(x) ~ x, hence:
> + log(1+x) - log(m) ~ c/m.
> +
> + We therefore calculate log1p(x) by k*log2 + log1p(f) + c/m. */
> +
> + /* Obtain correctly scaled k by manipulation in the exponent.
> + The scalar algorithm casts down to 32-bit at this point to calculate k and
> + u_red. We stay in double-width to obtain f and k, using the same constants
> + as the scalar algorithm but shifted left by 32. */
> + svfloat64_t m = svadd_x (pg, x, 1);
> + svuint64_t mi = svreinterpret_u64 (m);
> + svuint64_t u = svadd_x (pg, mi, d->onemhfrt2_top);
> +
> + svint64_t ki = svsub_x (pg, svreinterpret_s64 (svlsr_x (pg, u, 52)), 0x3ff);
> + svfloat64_t k = svcvt_f64_x (pg, ki);
> +
> + /* Reduce x to f in [sqrt(2)/2, sqrt(2)]. */
> + svuint64_t utop
> + = svadd_x (pg, svand_x (pg, u, 0x000fffff00000000), d->hfrt2_top);
> + svuint64_t u_red = svorr_x (pg, utop, svand_x (pg, mi, BottomMask));
> + svfloat64_t f = svsub_x (pg, svreinterpret_f64 (u_red), 1);
> +
> + /* Correction term c/m. */
> + svfloat64_t cm = svdiv_x (pg, svsub_x (pg, x, svsub_x (pg, m, 1)), m);
> +
> + /* Approximate log1p(x) on the reduced input using a polynomial. Because
> + log1p(0)=0 we choose an approximation of the form:
> + x + C0*x^2 + C1*x^3 + C2x^4 + ...
> + Hence approximation has the form f + f^2 * P(f)
> + where P(x) = C0 + C1*x + C2x^2 + ...
> + Assembling this all correctly is dealt with at the final step. */
> + svfloat64_t f2 = svmul_x (pg, f, f), f4 = svmul_x (pg, f2, f2),
> + f8 = svmul_x (pg, f4, f4), f16 = svmul_x (pg, f8, f8);
> + svfloat64_t p = sv_estrin_18_f64_x (pg, f, f2, f4, f8, f16, d->poly);
> +
> + svfloat64_t ylo = svmla_x (pg, cm, k, d->ln2_lo);
> + svfloat64_t yhi = svmla_x (pg, f, k, d->ln2_hi);
> + svfloat64_t y = svmla_x (pg, svadd_x (pg, ylo, yhi), f2, p);
> +
> + if (__glibc_unlikely (svptest_any (pg, special)))
> + return special_case (special, x, y);
> +
> + return y;
> +}
> diff --git a/sysdeps/aarch64/fpu/log1pf_advsimd.c b/sysdeps/aarch64/fpu/log1pf_advsimd.c
> new file mode 100644
> index 0000000000..3748830de8
> --- /dev/null
> +++ b/sysdeps/aarch64/fpu/log1pf_advsimd.c
> @@ -0,0 +1,128 @@
> +/* Single-precision AdvSIMD log1p
> +
> + Copyright (C) 2023 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 "v_math.h"
> +#include "poly_advsimd_f32.h"
> +
> +const static struct data
> +{
> + float32x4_t poly[8], ln2;
> + uint32x4_t tiny_bound, minus_one, four, thresh;
> + int32x4_t three_quarters;
> +} data = {
> + .poly = { /* Generated using FPMinimax in [-0.25, 0.5]. First two coefficients
> + (1, -0.5) are not stored as they can be generated more
> + efficiently. */
> + V4 (0x1.5555aap-2f), V4 (-0x1.000038p-2f), V4 (0x1.99675cp-3f),
> + V4 (-0x1.54ef78p-3f), V4 (0x1.28a1f4p-3f), V4 (-0x1.0da91p-3f),
> + V4 (0x1.abcb6p-4f), V4 (-0x1.6f0d5ep-5f) },
> + .ln2 = V4 (0x1.62e43p-1f),
> + .tiny_bound = V4 (0x34000000), /* asuint32(0x1p-23). ulp=0.5 at 0x1p-23. */
> + .thresh = V4 (0x4b800000), /* asuint32(INFINITY) - tiny_bound. */
> + .minus_one = V4 (0xbf800000),
> + .four = V4 (0x40800000),
> + .three_quarters = V4 (0x3f400000)
> +};
> +
> +static inline float32x4_t
> +eval_poly (float32x4_t m, const float32x4_t *p)
> +{
> + /* Approximate log(1+m) on [-0.25, 0.5] using split Estrin scheme. */
> + float32x4_t p_12 = vfmaq_f32 (v_f32 (-0.5), m, p[0]);
> + float32x4_t p_34 = vfmaq_f32 (p[1], m, p[2]);
> + float32x4_t p_56 = vfmaq_f32 (p[3], m, p[4]);
> + float32x4_t p_78 = vfmaq_f32 (p[5], m, p[6]);
> +
> + float32x4_t m2 = vmulq_f32 (m, m);
> + float32x4_t p_02 = vfmaq_f32 (m, m2, p_12);
> + float32x4_t p_36 = vfmaq_f32 (p_34, m2, p_56);
> + float32x4_t p_79 = vfmaq_f32 (p_78, m2, p[7]);
> +
> + float32x4_t m4 = vmulq_f32 (m2, m2);
> + float32x4_t p_06 = vfmaq_f32 (p_02, m4, p_36);
> + return vfmaq_f32 (p_06, m4, vmulq_f32 (m4, p_79));
> +}
> +
> +static float32x4_t NOINLINE VPCS_ATTR
> +special_case (float32x4_t x, float32x4_t y, uint32x4_t special)
> +{
> + return v_call_f32 (log1pf, x, y, special);
> +}
> +
> +/* Vector log1pf approximation using polynomial on reduced interval. Accuracy
> + is roughly 2.02 ULP:
> + log1pf(0x1.21e13ap-2) got 0x1.fe8028p-3 want 0x1.fe802cp-3. */
> +VPCS_ATTR float32x4_t V_NAME_F1 (log1p) (float32x4_t x)
> +{
> + const struct data *d = ptr_barrier (&data);
> +
> + uint32x4_t ix = vreinterpretq_u32_f32 (x);
> + uint32x4_t ia = vreinterpretq_u32_f32 (vabsq_f32 (x));
> + uint32x4_t special_cases
> + = vorrq_u32 (vcgeq_u32 (vsubq_u32 (ia, d->tiny_bound), d->thresh),
> + vcgeq_u32 (ix, d->minus_one));
> + float32x4_t special_arg = x;
> +
> +#if WANT_SIMD_EXCEPT
> + if (__glibc_unlikely (v_any_u32 (special_cases)))
> + /* Side-step special lanes so fenv exceptions are not triggered
> + inadvertently. */
> + x = v_zerofy_f32 (x, special_cases);
> +#endif
> +
> + /* With x + 1 = t * 2^k (where t = m + 1 and k is chosen such that m
> + is in [-0.25, 0.5]):
> + log1p(x) = log(t) + log(2^k) = log1p(m) + k*log(2).
> +
> + We approximate log1p(m) with a polynomial, then scale by
> + k*log(2). Instead of doing this directly, we use an intermediate
> + scale factor s = 4*k*log(2) to ensure the scale is representable
> + as a normalised fp32 number. */
> +
> + float32x4_t m = vaddq_f32 (x, v_f32 (1.0f));
> +
> + /* Choose k to scale x to the range [-1/4, 1/2]. */
> + int32x4_t k
> + = vandq_s32 (vsubq_s32 (vreinterpretq_s32_f32 (m), d->three_quarters),
> + v_s32 (0xff800000));
> + uint32x4_t ku = vreinterpretq_u32_s32 (k);
> +
> + /* Scale x by exponent manipulation. */
> + float32x4_t m_scale
> + = vreinterpretq_f32_u32 (vsubq_u32 (vreinterpretq_u32_f32 (x), ku));
> +
> + /* Scale up to ensure that the scale factor is representable as normalised
> + fp32 number, and scale m down accordingly. */
> + float32x4_t s = vreinterpretq_f32_u32 (vsubq_u32 (d->four, ku));
> + m_scale = vaddq_f32 (m_scale, vfmaq_f32 (v_f32 (-1.0f), v_f32 (0.25f), s));
> +
> + /* Evaluate polynomial on the reduced interval. */
> + float32x4_t p = eval_poly (m_scale, d->poly);
> +
> + /* The scale factor to be applied back at the end - by multiplying float(k)
> + by 2^-23 we get the unbiased exponent of k. */
> + float32x4_t scale_back = vcvtq_f32_s32 (vshrq_n_s32 (k, 23));
> +
> + /* Apply the scaling back. */
> + float32x4_t y = vfmaq_f32 (p, scale_back, d->ln2);
> +
> + if (__glibc_unlikely (v_any_u32 (special_cases)))
> + return special_case (special_arg, y, special_cases);
> + return y;
> +}
> diff --git a/sysdeps/aarch64/fpu/log1pf_sve.c b/sysdeps/aarch64/fpu/log1pf_sve.c
> new file mode 100644
> index 0000000000..712f62b9ce
> --- /dev/null
> +++ b/sysdeps/aarch64/fpu/log1pf_sve.c
> @@ -0,0 +1,100 @@
> +/* Single-precision SVE log1p
> +
> + Copyright (C) 2023 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"
> +#include "poly_sve_f32.h"
> +
> +static const struct data
> +{
> + float poly[8];
> + float ln2, exp_bias;
> + uint32_t four, three_quarters;
> +} data = {.poly = {/* Do not store first term of polynomial, which is -0.5, as
> + this can be fmov-ed directly instead of including it in
> + the main load-and-mla polynomial schedule. */
> + 0x1.5555aap-2f, -0x1.000038p-2f, 0x1.99675cp-3f,
> + -0x1.54ef78p-3f, 0x1.28a1f4p-3f, -0x1.0da91p-3f,
> + 0x1.abcb6p-4f, -0x1.6f0d5ep-5f},
> + .ln2 = 0x1.62e43p-1f,
> + .exp_bias = 0x1p-23f,
> + .four = 0x40800000,
> + .three_quarters = 0x3f400000};
> +
> +#define SignExponentMask 0xff800000
> +
> +static svfloat32_t NOINLINE
> +special_case (svfloat32_t x, svfloat32_t y, svbool_t special)
> +{
> + return sv_call_f32 (log1pf, x, y, special);
> +}
> +
> +/* Vector log1pf approximation using polynomial on reduced interval. Worst-case
> + error is 1.27 ULP very close to 0.5.
> + _ZGVsMxv_log1pf(0x1.fffffep-2) got 0x1.9f324p-2
> + want 0x1.9f323ep-2. */
> +svfloat32_t SV_NAME_F1 (log1p) (svfloat32_t x, svbool_t pg)
> +{
> + const struct data *d = ptr_barrier (&data);
> + /* x < -1, Inf/Nan. */
> + svbool_t special = svcmpeq (pg, svreinterpret_u32 (x), 0x7f800000);
> + special = svorn_z (pg, special, svcmpge (pg, x, -1));
> +
> + /* With x + 1 = t * 2^k (where t = m + 1 and k is chosen such that m
> + is in [-0.25, 0.5]):
> + log1p(x) = log(t) + log(2^k) = log1p(m) + k*log(2).
> +
> + We approximate log1p(m) with a polynomial, then scale by
> + k*log(2). Instead of doing this directly, we use an intermediate
> + scale factor s = 4*k*log(2) to ensure the scale is representable
> + as a normalised fp32 number. */
> + svfloat32_t m = svadd_x (pg, x, 1);
> +
> + /* Choose k to scale x to the range [-1/4, 1/2]. */
> + svint32_t k
> + = svand_x (pg, svsub_x (pg, svreinterpret_s32 (m), d->three_quarters),
> + sv_s32 (SignExponentMask));
> +
> + /* Scale x by exponent manipulation. */
> + svfloat32_t m_scale = svreinterpret_f32 (
> + svsub_x (pg, svreinterpret_u32 (x), svreinterpret_u32 (k)));
> +
> + /* Scale up to ensure that the scale factor is representable as normalised
> + fp32 number, and scale m down accordingly. */
> + svfloat32_t s = svreinterpret_f32 (svsubr_x (pg, k, d->four));
> + m_scale = svadd_x (pg, m_scale, svmla_x (pg, sv_f32 (-1), s, 0.25));
> +
> + /* Evaluate polynomial on reduced interval. */
> + svfloat32_t ms2 = svmul_x (pg, m_scale, m_scale),
> + ms4 = svmul_x (pg, ms2, ms2);
> + svfloat32_t p = sv_estrin_7_f32_x (pg, m_scale, ms2, ms4, d->poly);
> + p = svmad_x (pg, m_scale, p, -0.5);
> + p = svmla_x (pg, m_scale, m_scale, svmul_x (pg, m_scale, p));
> +
> + /* The scale factor to be applied back at the end - by multiplying float(k)
> + by 2^-23 we get the unbiased exponent of k. */
> + svfloat32_t scale_back = svmul_x (pg, svcvt_f32_x (pg, k), d->exp_bias);
> +
> + /* Apply the scaling back. */
> + svfloat32_t y = svmla_x (pg, p, scale_back, d->ln2);
> +
> + if (__glibc_unlikely (svptest_any (pg, special)))
> + return special_case (x, y, special);
> +
> + return y;
> +}
> diff --git a/sysdeps/aarch64/fpu/test-double-advsimd-wrappers.c b/sysdeps/aarch64/fpu/test-double-advsimd-wrappers.c
> index 0ac0240171..fc9e7aec47 100644
> --- a/sysdeps/aarch64/fpu/test-double-advsimd-wrappers.c
> +++ b/sysdeps/aarch64/fpu/test-double-advsimd-wrappers.c
> @@ -33,6 +33,7 @@ VPCS_VECTOR_WRAPPER (exp10_advsimd, _ZGVnN2v_exp10)
> VPCS_VECTOR_WRAPPER (exp2_advsimd, _ZGVnN2v_exp2)
> VPCS_VECTOR_WRAPPER (log_advsimd, _ZGVnN2v_log)
> VPCS_VECTOR_WRAPPER (log10_advsimd, _ZGVnN2v_log10)
> +VPCS_VECTOR_WRAPPER (log1p_advsimd, _ZGVnN2v_log1p)
> VPCS_VECTOR_WRAPPER (log2_advsimd, _ZGVnN2v_log2)
> VPCS_VECTOR_WRAPPER (sin_advsimd, _ZGVnN2v_sin)
> VPCS_VECTOR_WRAPPER (tan_advsimd, _ZGVnN2v_tan)
> diff --git a/sysdeps/aarch64/fpu/test-double-sve-wrappers.c b/sysdeps/aarch64/fpu/test-double-sve-wrappers.c
> index 5bbc4d58c1..aea589d5fb 100644
> --- a/sysdeps/aarch64/fpu/test-double-sve-wrappers.c
> +++ b/sysdeps/aarch64/fpu/test-double-sve-wrappers.c
> @@ -52,6 +52,7 @@ SVE_VECTOR_WRAPPER (exp10_sve, _ZGVsMxv_exp10)
> SVE_VECTOR_WRAPPER (exp2_sve, _ZGVsMxv_exp2)
> SVE_VECTOR_WRAPPER (log_sve, _ZGVsMxv_log)
> SVE_VECTOR_WRAPPER (log10_sve, _ZGVsMxv_log10)
> +SVE_VECTOR_WRAPPER (log1p_sve, _ZGVsMxv_log1p)
> SVE_VECTOR_WRAPPER (log2_sve, _ZGVsMxv_log2)
> SVE_VECTOR_WRAPPER (sin_sve, _ZGVsMxv_sin)
> SVE_VECTOR_WRAPPER (tan_sve, _ZGVsMxv_tan)
> diff --git a/sysdeps/aarch64/fpu/test-float-advsimd-wrappers.c b/sysdeps/aarch64/fpu/test-float-advsimd-wrappers.c
> index a557bfc3a6..446fd7f538 100644
> --- a/sysdeps/aarch64/fpu/test-float-advsimd-wrappers.c
> +++ b/sysdeps/aarch64/fpu/test-float-advsimd-wrappers.c
> @@ -33,6 +33,7 @@ VPCS_VECTOR_WRAPPER (exp10f_advsimd, _ZGVnN4v_exp10f)
> VPCS_VECTOR_WRAPPER (exp2f_advsimd, _ZGVnN4v_exp2f)
> VPCS_VECTOR_WRAPPER (logf_advsimd, _ZGVnN4v_logf)
> VPCS_VECTOR_WRAPPER (log10f_advsimd, _ZGVnN4v_log10f)
> +VPCS_VECTOR_WRAPPER (log1pf_advsimd, _ZGVnN4v_log1pf)
> VPCS_VECTOR_WRAPPER (log2f_advsimd, _ZGVnN4v_log2f)
> VPCS_VECTOR_WRAPPER (sinf_advsimd, _ZGVnN4v_sinf)
> VPCS_VECTOR_WRAPPER (tanf_advsimd, _ZGVnN4v_tanf)
> diff --git a/sysdeps/aarch64/fpu/test-float-sve-wrappers.c b/sysdeps/aarch64/fpu/test-float-sve-wrappers.c
> index f36939e2c4..ac17f60856 100644
> --- a/sysdeps/aarch64/fpu/test-float-sve-wrappers.c
> +++ b/sysdeps/aarch64/fpu/test-float-sve-wrappers.c
> @@ -52,6 +52,7 @@ SVE_VECTOR_WRAPPER (exp10f_sve, _ZGVsMxv_exp10f)
> SVE_VECTOR_WRAPPER (exp2f_sve, _ZGVsMxv_exp2f)
> SVE_VECTOR_WRAPPER (logf_sve, _ZGVsMxv_logf)
> SVE_VECTOR_WRAPPER (log10f_sve, _ZGVsMxv_log10f)
> +SVE_VECTOR_WRAPPER (log1pf_sve, _ZGVsMxv_log1pf)
> SVE_VECTOR_WRAPPER (log2f_sve, _ZGVsMxv_log2f)
> SVE_VECTOR_WRAPPER (sinf_sve, _ZGVsMxv_sinf)
> SVE_VECTOR_WRAPPER (tanf_sve, _ZGVsMxv_tanf)
> diff --git a/sysdeps/aarch64/libm-test-ulps b/sysdeps/aarch64/libm-test-ulps
> index e0699c44d8..a6b2f29a6f 100644
> --- a/sysdeps/aarch64/libm-test-ulps
> +++ b/sysdeps/aarch64/libm-test-ulps
> @@ -1248,11 +1248,19 @@ double: 1
> float: 1
> ldouble: 3
>
> +Function: "log1p_advsimd":
> +double: 1
> +float: 1
> +
> Function: "log1p_downward":
> double: 1
> float: 2
> ldouble: 3
>
> +Function: "log1p_sve":
> +double: 1
> +float: 1
> +
> Function: "log1p_towardzero":
> double: 2
> float: 2
> diff --git a/sysdeps/unix/sysv/linux/aarch64/libmvec.abilist b/sysdeps/unix/sysv/linux/aarch64/libmvec.abilist
> index 7961a2f374..0f20b5be29 100644
> --- a/sysdeps/unix/sysv/linux/aarch64/libmvec.abilist
> +++ b/sysdeps/unix/sysv/linux/aarch64/libmvec.abilist
> @@ -20,6 +20,7 @@ GLIBC_2.39 _ZGVnN2v_atan F
> GLIBC_2.39 _ZGVnN2v_exp10 F
> GLIBC_2.39 _ZGVnN2v_exp2 F
> GLIBC_2.39 _ZGVnN2v_log10 F
> +GLIBC_2.39 _ZGVnN2v_log1p F
> GLIBC_2.39 _ZGVnN2v_log2 F
> GLIBC_2.39 _ZGVnN2v_tan F
> GLIBC_2.39 _ZGVnN2vv_atan2 F
> @@ -29,6 +30,7 @@ GLIBC_2.39 _ZGVnN4v_atanf F
> GLIBC_2.39 _ZGVnN4v_exp10f F
> GLIBC_2.39 _ZGVnN4v_exp2f F
> GLIBC_2.39 _ZGVnN4v_log10f F
> +GLIBC_2.39 _ZGVnN4v_log1pf F
> GLIBC_2.39 _ZGVnN4v_log2f F
> GLIBC_2.39 _ZGVnN4v_tanf F
> GLIBC_2.39 _ZGVnN4vv_atan2f F
> @@ -44,6 +46,8 @@ GLIBC_2.39 _ZGVsMxv_exp2 F
> GLIBC_2.39 _ZGVsMxv_exp2f F
> GLIBC_2.39 _ZGVsMxv_log10 F
> GLIBC_2.39 _ZGVsMxv_log10f F
> +GLIBC_2.39 _ZGVsMxv_log1p F
> +GLIBC_2.39 _ZGVsMxv_log1pf F
> GLIBC_2.39 _ZGVsMxv_log2 F
> GLIBC_2.39 _ZGVsMxv_log2f F
> GLIBC_2.39 _ZGVsMxv_tan F
> --
> 2.27.0
>
@@ -6577,7 +6577,7 @@ log10 0xf.bf1b2p-4
log10 0x1.6b5f7ap+96
log1p 0
-log1p -0
+log1p -0 no-mathvec
log1p e-1
log1p -0.25
log1p -0.875
@@ -23,31 +23,31 @@ log1p 0
= log1p tonearest ibm128 0x0p+0 : 0x0p+0 : inexact-ok
= log1p towardzero ibm128 0x0p+0 : 0x0p+0 : inexact-ok
= log1p upward ibm128 0x0p+0 : 0x0p+0 : inexact-ok
-log1p -0
-= log1p downward binary32 -0x0p+0 : -0x0p+0 : inexact-ok
-= log1p tonearest binary32 -0x0p+0 : -0x0p+0 : inexact-ok
-= log1p towardzero binary32 -0x0p+0 : -0x0p+0 : inexact-ok
-= log1p upward binary32 -0x0p+0 : -0x0p+0 : inexact-ok
-= log1p downward binary64 -0x0p+0 : -0x0p+0 : inexact-ok
-= log1p tonearest binary64 -0x0p+0 : -0x0p+0 : inexact-ok
-= log1p towardzero binary64 -0x0p+0 : -0x0p+0 : inexact-ok
-= log1p upward binary64 -0x0p+0 : -0x0p+0 : inexact-ok
-= log1p downward intel96 -0x0p+0 : -0x0p+0 : inexact-ok
-= log1p tonearest intel96 -0x0p+0 : -0x0p+0 : inexact-ok
-= log1p towardzero intel96 -0x0p+0 : -0x0p+0 : inexact-ok
-= log1p upward intel96 -0x0p+0 : -0x0p+0 : inexact-ok
-= log1p downward m68k96 -0x0p+0 : -0x0p+0 : inexact-ok
-= log1p tonearest m68k96 -0x0p+0 : -0x0p+0 : inexact-ok
-= log1p towardzero m68k96 -0x0p+0 : -0x0p+0 : inexact-ok
-= log1p upward m68k96 -0x0p+0 : -0x0p+0 : inexact-ok
-= log1p downward binary128 -0x0p+0 : -0x0p+0 : inexact-ok
-= log1p tonearest binary128 -0x0p+0 : -0x0p+0 : inexact-ok
-= log1p towardzero binary128 -0x0p+0 : -0x0p+0 : inexact-ok
-= log1p upward binary128 -0x0p+0 : -0x0p+0 : inexact-ok
-= log1p downward ibm128 -0x0p+0 : -0x0p+0 : inexact-ok
-= log1p tonearest ibm128 -0x0p+0 : -0x0p+0 : inexact-ok
-= log1p towardzero ibm128 -0x0p+0 : -0x0p+0 : inexact-ok
-= log1p upward ibm128 -0x0p+0 : -0x0p+0 : inexact-ok
+log1p -0 no-mathvec
+= log1p downward binary32 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
+= log1p tonearest binary32 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
+= log1p towardzero binary32 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
+= log1p upward binary32 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
+= log1p downward binary64 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
+= log1p tonearest binary64 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
+= log1p towardzero binary64 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
+= log1p upward binary64 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
+= log1p downward intel96 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
+= log1p tonearest intel96 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
+= log1p towardzero intel96 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
+= log1p upward intel96 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
+= log1p downward m68k96 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
+= log1p tonearest m68k96 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
+= log1p towardzero m68k96 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
+= log1p upward m68k96 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
+= log1p downward binary128 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
+= log1p tonearest binary128 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
+= log1p towardzero binary128 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
+= log1p upward binary128 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
+= log1p downward ibm128 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
+= log1p tonearest ibm128 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
+= log1p towardzero ibm128 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
+= log1p upward ibm128 -0x0p+0 : -0x0p+0 : no-mathvec inexact-ok
log1p e-1
= log1p downward binary32 0x1.b7e152p+0 : 0x1p+0 : inexact-ok
= log1p tonearest binary32 0x1.b7e152p+0 : 0x1p+0 : inexact-ok
@@ -8,6 +8,7 @@ libmvec-supported-funcs = acos \
exp2 \
log \
log10 \
+ log1p \
log2 \
sin \
tan
@@ -46,6 +46,10 @@ libmvec {
_ZGVnN2v_log10;
_ZGVsMxv_log10f;
_ZGVsMxv_log10;
+ _ZGVnN4v_log1pf;
+ _ZGVnN2v_log1p;
+ _ZGVsMxv_log1pf;
+ _ZGVsMxv_log1p;
_ZGVnN4v_log2f;
_ZGVnN2v_log2;
_ZGVsMxv_log2f;
@@ -59,6 +59,7 @@ __vpcs __f32x4_t _ZGVnN4v_exp10f (__f32x4_t);
__vpcs __f32x4_t _ZGVnN4v_exp2f (__f32x4_t);
__vpcs __f32x4_t _ZGVnN4v_logf (__f32x4_t);
__vpcs __f32x4_t _ZGVnN4v_log10f (__f32x4_t);
+__vpcs __f32x4_t _ZGVnN4v_log1pf (__f32x4_t);
__vpcs __f32x4_t _ZGVnN4v_log2f (__f32x4_t);
__vpcs __f32x4_t _ZGVnN4v_sinf (__f32x4_t);
__vpcs __f32x4_t _ZGVnN4v_tanf (__f32x4_t);
@@ -73,6 +74,7 @@ __vpcs __f64x2_t _ZGVnN2v_exp10 (__f64x2_t);
__vpcs __f64x2_t _ZGVnN2v_exp2 (__f64x2_t);
__vpcs __f64x2_t _ZGVnN2v_log (__f64x2_t);
__vpcs __f64x2_t _ZGVnN2v_log10 (__f64x2_t);
+__vpcs __f64x2_t _ZGVnN2v_log1p (__f64x2_t);
__vpcs __f64x2_t _ZGVnN2v_log2 (__f64x2_t);
__vpcs __f64x2_t _ZGVnN2v_sin (__f64x2_t);
__vpcs __f64x2_t _ZGVnN2v_tan (__f64x2_t);
@@ -92,6 +94,7 @@ __sv_f32_t _ZGVsMxv_exp10f (__sv_f32_t, __sv_bool_t);
__sv_f32_t _ZGVsMxv_exp2f (__sv_f32_t, __sv_bool_t);
__sv_f32_t _ZGVsMxv_logf (__sv_f32_t, __sv_bool_t);
__sv_f32_t _ZGVsMxv_log10f (__sv_f32_t, __sv_bool_t);
+__sv_f32_t _ZGVsMxv_log1pf (__sv_f32_t, __sv_bool_t);
__sv_f32_t _ZGVsMxv_log2f (__sv_f32_t, __sv_bool_t);
__sv_f32_t _ZGVsMxv_sinf (__sv_f32_t, __sv_bool_t);
__sv_f32_t _ZGVsMxv_tanf (__sv_f32_t, __sv_bool_t);
@@ -106,6 +109,7 @@ __sv_f64_t _ZGVsMxv_exp10 (__sv_f64_t, __sv_bool_t);
__sv_f64_t _ZGVsMxv_exp2 (__sv_f64_t, __sv_bool_t);
__sv_f64_t _ZGVsMxv_log (__sv_f64_t, __sv_bool_t);
__sv_f64_t _ZGVsMxv_log10 (__sv_f64_t, __sv_bool_t);
+__sv_f64_t _ZGVsMxv_log1p (__sv_f64_t, __sv_bool_t);
__sv_f64_t _ZGVsMxv_log2 (__sv_f64_t, __sv_bool_t);
__sv_f64_t _ZGVsMxv_sin (__sv_f64_t, __sv_bool_t);
__sv_f64_t _ZGVsMxv_tan (__sv_f64_t, __sv_bool_t);
new file mode 100644
@@ -0,0 +1,129 @@
+/* Double-precision AdvSIMD log1p
+
+ Copyright (C) 2023 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 "v_math.h"
+#include "poly_advsimd_f64.h"
+
+const static struct data
+{
+ float64x2_t poly[19], ln2[2];
+ uint64x2_t hf_rt2_top, one_m_hf_rt2_top, umask, inf, minus_one;
+ int64x2_t one_top;
+} data = {
+ /* Generated using Remez, deg=20, in [sqrt(2)/2-1, sqrt(2)-1]. */
+ .poly = { V2 (-0x1.ffffffffffffbp-2), V2 (0x1.55555555551a9p-2),
+ V2 (-0x1.00000000008e3p-2), V2 (0x1.9999999a32797p-3),
+ V2 (-0x1.555555552fecfp-3), V2 (0x1.249248e071e5ap-3),
+ V2 (-0x1.ffffff8bf8482p-4), V2 (0x1.c71c8f07da57ap-4),
+ V2 (-0x1.9999ca4ccb617p-4), V2 (0x1.7459ad2e1dfa3p-4),
+ V2 (-0x1.554d2680a3ff2p-4), V2 (0x1.3b4c54d487455p-4),
+ V2 (-0x1.2548a9ffe80e6p-4), V2 (0x1.0f389a24b2e07p-4),
+ V2 (-0x1.eee4db15db335p-5), V2 (0x1.e95b494d4a5ddp-5),
+ V2 (-0x1.15fdf07cb7c73p-4), V2 (0x1.0310b70800fcfp-4),
+ V2 (-0x1.cfa7385bdb37ep-6) },
+ .ln2 = { V2 (0x1.62e42fefa3800p-1), V2 (0x1.ef35793c76730p-45) },
+ /* top32(asuint64(sqrt(2)/2)) << 32. */
+ .hf_rt2_top = V2 (0x3fe6a09e00000000),
+ /* (top32(asuint64(1)) - top32(asuint64(sqrt(2)/2))) << 32. */
+ .one_m_hf_rt2_top = V2 (0x00095f6200000000),
+ .umask = V2 (0x000fffff00000000),
+ .one_top = V2 (0x3ff),
+ .inf = V2 (0x7ff0000000000000),
+ .minus_one = V2 (0xbff0000000000000)
+};
+
+#define BottomMask v_u64 (0xffffffff)
+
+static float64x2_t VPCS_ATTR NOINLINE
+special_case (float64x2_t x, float64x2_t y, uint64x2_t special)
+{
+ return v_call_f64 (log1p, x, y, special);
+}
+
+/* Vector log1p approximation using polynomial on reduced interval. Routine is
+ a modification of the algorithm used in scalar log1p, with no shortcut for
+ k=0 and no narrowing for f and k. Maximum observed error is 2.45 ULP:
+ _ZGVnN2v_log1p(0x1.658f7035c4014p+11) got 0x1.fd61d0727429dp+2
+ want 0x1.fd61d0727429fp+2 . */
+VPCS_ATTR float64x2_t V_NAME_D1 (log1p) (float64x2_t x)
+{
+ const struct data *d = ptr_barrier (&data);
+ uint64x2_t ix = vreinterpretq_u64_f64 (x);
+ uint64x2_t ia = vreinterpretq_u64_f64 (vabsq_f64 (x));
+ uint64x2_t special = vcgeq_u64 (ia, d->inf);
+
+#if WANT_SIMD_EXCEPT
+ special = vorrq_u64 (special,
+ vcgeq_u64 (ix, vreinterpretq_u64_f64 (v_f64 (-1))));
+ if (__glibc_unlikely (v_any_u64 (special)))
+ x = v_zerofy_f64 (x, special);
+#else
+ special = vorrq_u64 (special, vcleq_f64 (x, v_f64 (-1)));
+#endif
+
+ /* With x + 1 = t * 2^k (where t = f + 1 and k is chosen such that f
+ is in [sqrt(2)/2, sqrt(2)]):
+ log1p(x) = k*log(2) + log1p(f).
+
+ f may not be representable exactly, so we need a correction term:
+ let m = round(1 + x), c = (1 + x) - m.
+ c << m: at very small x, log1p(x) ~ x, hence:
+ log(1+x) - log(m) ~ c/m.
+
+ We therefore calculate log1p(x) by k*log2 + log1p(f) + c/m. */
+
+ /* Obtain correctly scaled k by manipulation in the exponent.
+ The scalar algorithm casts down to 32-bit at this point to calculate k and
+ u_red. We stay in double-width to obtain f and k, using the same constants
+ as the scalar algorithm but shifted left by 32. */
+ float64x2_t m = vaddq_f64 (x, v_f64 (1));
+ uint64x2_t mi = vreinterpretq_u64_f64 (m);
+ uint64x2_t u = vaddq_u64 (mi, d->one_m_hf_rt2_top);
+
+ int64x2_t ki
+ = vsubq_s64 (vreinterpretq_s64_u64 (vshrq_n_u64 (u, 52)), d->one_top);
+ float64x2_t k = vcvtq_f64_s64 (ki);
+
+ /* Reduce x to f in [sqrt(2)/2, sqrt(2)]. */
+ uint64x2_t utop = vaddq_u64 (vandq_u64 (u, d->umask), d->hf_rt2_top);
+ uint64x2_t u_red = vorrq_u64 (utop, vandq_u64 (mi, BottomMask));
+ float64x2_t f = vsubq_f64 (vreinterpretq_f64_u64 (u_red), v_f64 (1));
+
+ /* Correction term c/m. */
+ float64x2_t cm = vdivq_f64 (vsubq_f64 (x, vsubq_f64 (m, v_f64 (1))), m);
+
+ /* Approximate log1p(x) on the reduced input using a polynomial. Because
+ log1p(0)=0 we choose an approximation of the form:
+ x + C0*x^2 + C1*x^3 + C2x^4 + ...
+ Hence approximation has the form f + f^2 * P(f)
+ where P(x) = C0 + C1*x + C2x^2 + ...
+ Assembling this all correctly is dealt with at the final step. */
+ float64x2_t f2 = vmulq_f64 (f, f);
+ float64x2_t p = v_pw_horner_18_f64 (f, f2, d->poly);
+
+ float64x2_t ylo = vfmaq_f64 (cm, k, d->ln2[1]);
+ float64x2_t yhi = vfmaq_f64 (f, k, d->ln2[0]);
+ float64x2_t y = vaddq_f64 (ylo, yhi);
+
+ if (__glibc_unlikely (v_any_u64 (special)))
+ return special_case (vreinterpretq_f64_u64 (ix), vfmaq_f64 (y, f2, p),
+ special);
+
+ return vfmaq_f64 (y, f2, p);
+}
new file mode 100644
@@ -0,0 +1,118 @@
+/* Double-precision SVE log1p
+
+ Copyright (C) 2023 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"
+#include "poly_sve_f64.h"
+
+static const struct data
+{
+ double poly[19];
+ double ln2_hi, ln2_lo;
+ uint64_t hfrt2_top, onemhfrt2_top, inf, mone;
+} data = {
+ /* Generated using Remez in [ sqrt(2)/2 - 1, sqrt(2) - 1]. Order 20
+ polynomial, however first 2 coefficients are 0 and 1 so are not stored. */
+ .poly = { -0x1.ffffffffffffbp-2, 0x1.55555555551a9p-2, -0x1.00000000008e3p-2,
+ 0x1.9999999a32797p-3, -0x1.555555552fecfp-3, 0x1.249248e071e5ap-3,
+ -0x1.ffffff8bf8482p-4, 0x1.c71c8f07da57ap-4, -0x1.9999ca4ccb617p-4,
+ 0x1.7459ad2e1dfa3p-4, -0x1.554d2680a3ff2p-4, 0x1.3b4c54d487455p-4,
+ -0x1.2548a9ffe80e6p-4, 0x1.0f389a24b2e07p-4, -0x1.eee4db15db335p-5,
+ 0x1.e95b494d4a5ddp-5, -0x1.15fdf07cb7c73p-4, 0x1.0310b70800fcfp-4,
+ -0x1.cfa7385bdb37ep-6, },
+ .ln2_hi = 0x1.62e42fefa3800p-1,
+ .ln2_lo = 0x1.ef35793c76730p-45,
+ /* top32(asuint64(sqrt(2)/2)) << 32. */
+ .hfrt2_top = 0x3fe6a09e00000000,
+ /* (top32(asuint64(1)) - top32(asuint64(sqrt(2)/2))) << 32. */
+ .onemhfrt2_top = 0x00095f6200000000,
+ .inf = 0x7ff0000000000000,
+ .mone = 0xbff0000000000000,
+};
+
+#define AbsMask 0x7fffffffffffffff
+#define BottomMask 0xffffffff
+
+static svfloat64_t NOINLINE
+special_case (svbool_t special, svfloat64_t x, svfloat64_t y)
+{
+ return sv_call_f64 (log1p, x, y, special);
+}
+
+/* Vector approximation for log1p using polynomial on reduced interval. Maximum
+ observed error is 2.46 ULP:
+ _ZGVsMxv_log1p(0x1.654a1307242a4p+11) got 0x1.fd5565fb590f4p+2
+ want 0x1.fd5565fb590f6p+2. */
+svfloat64_t SV_NAME_D1 (log1p) (svfloat64_t x, svbool_t pg)
+{
+ const struct data *d = ptr_barrier (&data);
+ svuint64_t ix = svreinterpret_u64 (x);
+ svuint64_t ax = svand_x (pg, ix, AbsMask);
+ svbool_t special
+ = svorr_z (pg, svcmpge (pg, ax, d->inf), svcmpge (pg, ix, d->mone));
+
+ /* With x + 1 = t * 2^k (where t = f + 1 and k is chosen such that f
+ is in [sqrt(2)/2, sqrt(2)]):
+ log1p(x) = k*log(2) + log1p(f).
+
+ f may not be representable exactly, so we need a correction term:
+ let m = round(1 + x), c = (1 + x) - m.
+ c << m: at very small x, log1p(x) ~ x, hence:
+ log(1+x) - log(m) ~ c/m.
+
+ We therefore calculate log1p(x) by k*log2 + log1p(f) + c/m. */
+
+ /* Obtain correctly scaled k by manipulation in the exponent.
+ The scalar algorithm casts down to 32-bit at this point to calculate k and
+ u_red. We stay in double-width to obtain f and k, using the same constants
+ as the scalar algorithm but shifted left by 32. */
+ svfloat64_t m = svadd_x (pg, x, 1);
+ svuint64_t mi = svreinterpret_u64 (m);
+ svuint64_t u = svadd_x (pg, mi, d->onemhfrt2_top);
+
+ svint64_t ki = svsub_x (pg, svreinterpret_s64 (svlsr_x (pg, u, 52)), 0x3ff);
+ svfloat64_t k = svcvt_f64_x (pg, ki);
+
+ /* Reduce x to f in [sqrt(2)/2, sqrt(2)]. */
+ svuint64_t utop
+ = svadd_x (pg, svand_x (pg, u, 0x000fffff00000000), d->hfrt2_top);
+ svuint64_t u_red = svorr_x (pg, utop, svand_x (pg, mi, BottomMask));
+ svfloat64_t f = svsub_x (pg, svreinterpret_f64 (u_red), 1);
+
+ /* Correction term c/m. */
+ svfloat64_t cm = svdiv_x (pg, svsub_x (pg, x, svsub_x (pg, m, 1)), m);
+
+ /* Approximate log1p(x) on the reduced input using a polynomial. Because
+ log1p(0)=0 we choose an approximation of the form:
+ x + C0*x^2 + C1*x^3 + C2x^4 + ...
+ Hence approximation has the form f + f^2 * P(f)
+ where P(x) = C0 + C1*x + C2x^2 + ...
+ Assembling this all correctly is dealt with at the final step. */
+ svfloat64_t f2 = svmul_x (pg, f, f), f4 = svmul_x (pg, f2, f2),
+ f8 = svmul_x (pg, f4, f4), f16 = svmul_x (pg, f8, f8);
+ svfloat64_t p = sv_estrin_18_f64_x (pg, f, f2, f4, f8, f16, d->poly);
+
+ svfloat64_t ylo = svmla_x (pg, cm, k, d->ln2_lo);
+ svfloat64_t yhi = svmla_x (pg, f, k, d->ln2_hi);
+ svfloat64_t y = svmla_x (pg, svadd_x (pg, ylo, yhi), f2, p);
+
+ if (__glibc_unlikely (svptest_any (pg, special)))
+ return special_case (special, x, y);
+
+ return y;
+}
new file mode 100644
@@ -0,0 +1,128 @@
+/* Single-precision AdvSIMD log1p
+
+ Copyright (C) 2023 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 "v_math.h"
+#include "poly_advsimd_f32.h"
+
+const static struct data
+{
+ float32x4_t poly[8], ln2;
+ uint32x4_t tiny_bound, minus_one, four, thresh;
+ int32x4_t three_quarters;
+} data = {
+ .poly = { /* Generated using FPMinimax in [-0.25, 0.5]. First two coefficients
+ (1, -0.5) are not stored as they can be generated more
+ efficiently. */
+ V4 (0x1.5555aap-2f), V4 (-0x1.000038p-2f), V4 (0x1.99675cp-3f),
+ V4 (-0x1.54ef78p-3f), V4 (0x1.28a1f4p-3f), V4 (-0x1.0da91p-3f),
+ V4 (0x1.abcb6p-4f), V4 (-0x1.6f0d5ep-5f) },
+ .ln2 = V4 (0x1.62e43p-1f),
+ .tiny_bound = V4 (0x34000000), /* asuint32(0x1p-23). ulp=0.5 at 0x1p-23. */
+ .thresh = V4 (0x4b800000), /* asuint32(INFINITY) - tiny_bound. */
+ .minus_one = V4 (0xbf800000),
+ .four = V4 (0x40800000),
+ .three_quarters = V4 (0x3f400000)
+};
+
+static inline float32x4_t
+eval_poly (float32x4_t m, const float32x4_t *p)
+{
+ /* Approximate log(1+m) on [-0.25, 0.5] using split Estrin scheme. */
+ float32x4_t p_12 = vfmaq_f32 (v_f32 (-0.5), m, p[0]);
+ float32x4_t p_34 = vfmaq_f32 (p[1], m, p[2]);
+ float32x4_t p_56 = vfmaq_f32 (p[3], m, p[4]);
+ float32x4_t p_78 = vfmaq_f32 (p[5], m, p[6]);
+
+ float32x4_t m2 = vmulq_f32 (m, m);
+ float32x4_t p_02 = vfmaq_f32 (m, m2, p_12);
+ float32x4_t p_36 = vfmaq_f32 (p_34, m2, p_56);
+ float32x4_t p_79 = vfmaq_f32 (p_78, m2, p[7]);
+
+ float32x4_t m4 = vmulq_f32 (m2, m2);
+ float32x4_t p_06 = vfmaq_f32 (p_02, m4, p_36);
+ return vfmaq_f32 (p_06, m4, vmulq_f32 (m4, p_79));
+}
+
+static float32x4_t NOINLINE VPCS_ATTR
+special_case (float32x4_t x, float32x4_t y, uint32x4_t special)
+{
+ return v_call_f32 (log1pf, x, y, special);
+}
+
+/* Vector log1pf approximation using polynomial on reduced interval. Accuracy
+ is roughly 2.02 ULP:
+ log1pf(0x1.21e13ap-2) got 0x1.fe8028p-3 want 0x1.fe802cp-3. */
+VPCS_ATTR float32x4_t V_NAME_F1 (log1p) (float32x4_t x)
+{
+ const struct data *d = ptr_barrier (&data);
+
+ uint32x4_t ix = vreinterpretq_u32_f32 (x);
+ uint32x4_t ia = vreinterpretq_u32_f32 (vabsq_f32 (x));
+ uint32x4_t special_cases
+ = vorrq_u32 (vcgeq_u32 (vsubq_u32 (ia, d->tiny_bound), d->thresh),
+ vcgeq_u32 (ix, d->minus_one));
+ float32x4_t special_arg = x;
+
+#if WANT_SIMD_EXCEPT
+ if (__glibc_unlikely (v_any_u32 (special_cases)))
+ /* Side-step special lanes so fenv exceptions are not triggered
+ inadvertently. */
+ x = v_zerofy_f32 (x, special_cases);
+#endif
+
+ /* With x + 1 = t * 2^k (where t = m + 1 and k is chosen such that m
+ is in [-0.25, 0.5]):
+ log1p(x) = log(t) + log(2^k) = log1p(m) + k*log(2).
+
+ We approximate log1p(m) with a polynomial, then scale by
+ k*log(2). Instead of doing this directly, we use an intermediate
+ scale factor s = 4*k*log(2) to ensure the scale is representable
+ as a normalised fp32 number. */
+
+ float32x4_t m = vaddq_f32 (x, v_f32 (1.0f));
+
+ /* Choose k to scale x to the range [-1/4, 1/2]. */
+ int32x4_t k
+ = vandq_s32 (vsubq_s32 (vreinterpretq_s32_f32 (m), d->three_quarters),
+ v_s32 (0xff800000));
+ uint32x4_t ku = vreinterpretq_u32_s32 (k);
+
+ /* Scale x by exponent manipulation. */
+ float32x4_t m_scale
+ = vreinterpretq_f32_u32 (vsubq_u32 (vreinterpretq_u32_f32 (x), ku));
+
+ /* Scale up to ensure that the scale factor is representable as normalised
+ fp32 number, and scale m down accordingly. */
+ float32x4_t s = vreinterpretq_f32_u32 (vsubq_u32 (d->four, ku));
+ m_scale = vaddq_f32 (m_scale, vfmaq_f32 (v_f32 (-1.0f), v_f32 (0.25f), s));
+
+ /* Evaluate polynomial on the reduced interval. */
+ float32x4_t p = eval_poly (m_scale, d->poly);
+
+ /* The scale factor to be applied back at the end - by multiplying float(k)
+ by 2^-23 we get the unbiased exponent of k. */
+ float32x4_t scale_back = vcvtq_f32_s32 (vshrq_n_s32 (k, 23));
+
+ /* Apply the scaling back. */
+ float32x4_t y = vfmaq_f32 (p, scale_back, d->ln2);
+
+ if (__glibc_unlikely (v_any_u32 (special_cases)))
+ return special_case (special_arg, y, special_cases);
+ return y;
+}
new file mode 100644
@@ -0,0 +1,100 @@
+/* Single-precision SVE log1p
+
+ Copyright (C) 2023 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"
+#include "poly_sve_f32.h"
+
+static const struct data
+{
+ float poly[8];
+ float ln2, exp_bias;
+ uint32_t four, three_quarters;
+} data = {.poly = {/* Do not store first term of polynomial, which is -0.5, as
+ this can be fmov-ed directly instead of including it in
+ the main load-and-mla polynomial schedule. */
+ 0x1.5555aap-2f, -0x1.000038p-2f, 0x1.99675cp-3f,
+ -0x1.54ef78p-3f, 0x1.28a1f4p-3f, -0x1.0da91p-3f,
+ 0x1.abcb6p-4f, -0x1.6f0d5ep-5f},
+ .ln2 = 0x1.62e43p-1f,
+ .exp_bias = 0x1p-23f,
+ .four = 0x40800000,
+ .three_quarters = 0x3f400000};
+
+#define SignExponentMask 0xff800000
+
+static svfloat32_t NOINLINE
+special_case (svfloat32_t x, svfloat32_t y, svbool_t special)
+{
+ return sv_call_f32 (log1pf, x, y, special);
+}
+
+/* Vector log1pf approximation using polynomial on reduced interval. Worst-case
+ error is 1.27 ULP very close to 0.5.
+ _ZGVsMxv_log1pf(0x1.fffffep-2) got 0x1.9f324p-2
+ want 0x1.9f323ep-2. */
+svfloat32_t SV_NAME_F1 (log1p) (svfloat32_t x, svbool_t pg)
+{
+ const struct data *d = ptr_barrier (&data);
+ /* x < -1, Inf/Nan. */
+ svbool_t special = svcmpeq (pg, svreinterpret_u32 (x), 0x7f800000);
+ special = svorn_z (pg, special, svcmpge (pg, x, -1));
+
+ /* With x + 1 = t * 2^k (where t = m + 1 and k is chosen such that m
+ is in [-0.25, 0.5]):
+ log1p(x) = log(t) + log(2^k) = log1p(m) + k*log(2).
+
+ We approximate log1p(m) with a polynomial, then scale by
+ k*log(2). Instead of doing this directly, we use an intermediate
+ scale factor s = 4*k*log(2) to ensure the scale is representable
+ as a normalised fp32 number. */
+ svfloat32_t m = svadd_x (pg, x, 1);
+
+ /* Choose k to scale x to the range [-1/4, 1/2]. */
+ svint32_t k
+ = svand_x (pg, svsub_x (pg, svreinterpret_s32 (m), d->three_quarters),
+ sv_s32 (SignExponentMask));
+
+ /* Scale x by exponent manipulation. */
+ svfloat32_t m_scale = svreinterpret_f32 (
+ svsub_x (pg, svreinterpret_u32 (x), svreinterpret_u32 (k)));
+
+ /* Scale up to ensure that the scale factor is representable as normalised
+ fp32 number, and scale m down accordingly. */
+ svfloat32_t s = svreinterpret_f32 (svsubr_x (pg, k, d->four));
+ m_scale = svadd_x (pg, m_scale, svmla_x (pg, sv_f32 (-1), s, 0.25));
+
+ /* Evaluate polynomial on reduced interval. */
+ svfloat32_t ms2 = svmul_x (pg, m_scale, m_scale),
+ ms4 = svmul_x (pg, ms2, ms2);
+ svfloat32_t p = sv_estrin_7_f32_x (pg, m_scale, ms2, ms4, d->poly);
+ p = svmad_x (pg, m_scale, p, -0.5);
+ p = svmla_x (pg, m_scale, m_scale, svmul_x (pg, m_scale, p));
+
+ /* The scale factor to be applied back at the end - by multiplying float(k)
+ by 2^-23 we get the unbiased exponent of k. */
+ svfloat32_t scale_back = svmul_x (pg, svcvt_f32_x (pg, k), d->exp_bias);
+
+ /* Apply the scaling back. */
+ svfloat32_t y = svmla_x (pg, p, scale_back, d->ln2);
+
+ if (__glibc_unlikely (svptest_any (pg, special)))
+ return special_case (x, y, special);
+
+ return y;
+}
@@ -33,6 +33,7 @@ VPCS_VECTOR_WRAPPER (exp10_advsimd, _ZGVnN2v_exp10)
VPCS_VECTOR_WRAPPER (exp2_advsimd, _ZGVnN2v_exp2)
VPCS_VECTOR_WRAPPER (log_advsimd, _ZGVnN2v_log)
VPCS_VECTOR_WRAPPER (log10_advsimd, _ZGVnN2v_log10)
+VPCS_VECTOR_WRAPPER (log1p_advsimd, _ZGVnN2v_log1p)
VPCS_VECTOR_WRAPPER (log2_advsimd, _ZGVnN2v_log2)
VPCS_VECTOR_WRAPPER (sin_advsimd, _ZGVnN2v_sin)
VPCS_VECTOR_WRAPPER (tan_advsimd, _ZGVnN2v_tan)
@@ -52,6 +52,7 @@ SVE_VECTOR_WRAPPER (exp10_sve, _ZGVsMxv_exp10)
SVE_VECTOR_WRAPPER (exp2_sve, _ZGVsMxv_exp2)
SVE_VECTOR_WRAPPER (log_sve, _ZGVsMxv_log)
SVE_VECTOR_WRAPPER (log10_sve, _ZGVsMxv_log10)
+SVE_VECTOR_WRAPPER (log1p_sve, _ZGVsMxv_log1p)
SVE_VECTOR_WRAPPER (log2_sve, _ZGVsMxv_log2)
SVE_VECTOR_WRAPPER (sin_sve, _ZGVsMxv_sin)
SVE_VECTOR_WRAPPER (tan_sve, _ZGVsMxv_tan)
@@ -33,6 +33,7 @@ VPCS_VECTOR_WRAPPER (exp10f_advsimd, _ZGVnN4v_exp10f)
VPCS_VECTOR_WRAPPER (exp2f_advsimd, _ZGVnN4v_exp2f)
VPCS_VECTOR_WRAPPER (logf_advsimd, _ZGVnN4v_logf)
VPCS_VECTOR_WRAPPER (log10f_advsimd, _ZGVnN4v_log10f)
+VPCS_VECTOR_WRAPPER (log1pf_advsimd, _ZGVnN4v_log1pf)
VPCS_VECTOR_WRAPPER (log2f_advsimd, _ZGVnN4v_log2f)
VPCS_VECTOR_WRAPPER (sinf_advsimd, _ZGVnN4v_sinf)
VPCS_VECTOR_WRAPPER (tanf_advsimd, _ZGVnN4v_tanf)
@@ -52,6 +52,7 @@ SVE_VECTOR_WRAPPER (exp10f_sve, _ZGVsMxv_exp10f)
SVE_VECTOR_WRAPPER (exp2f_sve, _ZGVsMxv_exp2f)
SVE_VECTOR_WRAPPER (logf_sve, _ZGVsMxv_logf)
SVE_VECTOR_WRAPPER (log10f_sve, _ZGVsMxv_log10f)
+SVE_VECTOR_WRAPPER (log1pf_sve, _ZGVsMxv_log1pf)
SVE_VECTOR_WRAPPER (log2f_sve, _ZGVsMxv_log2f)
SVE_VECTOR_WRAPPER (sinf_sve, _ZGVsMxv_sinf)
SVE_VECTOR_WRAPPER (tanf_sve, _ZGVsMxv_tanf)
@@ -1248,11 +1248,19 @@ double: 1
float: 1
ldouble: 3
+Function: "log1p_advsimd":
+double: 1
+float: 1
+
Function: "log1p_downward":
double: 1
float: 2
ldouble: 3
+Function: "log1p_sve":
+double: 1
+float: 1
+
Function: "log1p_towardzero":
double: 2
float: 2
@@ -20,6 +20,7 @@ GLIBC_2.39 _ZGVnN2v_atan F
GLIBC_2.39 _ZGVnN2v_exp10 F
GLIBC_2.39 _ZGVnN2v_exp2 F
GLIBC_2.39 _ZGVnN2v_log10 F
+GLIBC_2.39 _ZGVnN2v_log1p F
GLIBC_2.39 _ZGVnN2v_log2 F
GLIBC_2.39 _ZGVnN2v_tan F
GLIBC_2.39 _ZGVnN2vv_atan2 F
@@ -29,6 +30,7 @@ GLIBC_2.39 _ZGVnN4v_atanf F
GLIBC_2.39 _ZGVnN4v_exp10f F
GLIBC_2.39 _ZGVnN4v_exp2f F
GLIBC_2.39 _ZGVnN4v_log10f F
+GLIBC_2.39 _ZGVnN4v_log1pf F
GLIBC_2.39 _ZGVnN4v_log2f F
GLIBC_2.39 _ZGVnN4v_tanf F
GLIBC_2.39 _ZGVnN4vv_atan2f F
@@ -44,6 +46,8 @@ GLIBC_2.39 _ZGVsMxv_exp2 F
GLIBC_2.39 _ZGVsMxv_exp2f F
GLIBC_2.39 _ZGVsMxv_log10 F
GLIBC_2.39 _ZGVsMxv_log10f F
+GLIBC_2.39 _ZGVsMxv_log1p F
+GLIBC_2.39 _ZGVsMxv_log1pf F
GLIBC_2.39 _ZGVsMxv_log2 F
GLIBC_2.39 _ZGVsMxv_log2f F
GLIBC_2.39 _ZGVsMxv_tan F