[PATCH 3/3] aarch64: Implement AdvSIMD and SVE rsqrt(f) routines
James Chesterman
James.Chesterman@arm.com
Fri Dec 5 10:37:45 GMT 2025
Vector variants of the new C23 rsqrt routines for both AdvSIMD and
SVE, as well as in both single and double precision.
---
OK for master? If so, please commit for me as I don't have commit rights.
Difference from version 1 is that the benchtests are split into their own commits.
Thanks,
James
bits/libm-simd-decl-stubs.h | 11 +++
math/bits/mathcalls.h | 2 +-
sysdeps/aarch64/fpu/Makefile | 1 +
sysdeps/aarch64/fpu/Versions | 5 ++
sysdeps/aarch64/fpu/advsimd_f32_protos.h | 1 +
sysdeps/aarch64/fpu/bits/math-vector.h | 8 ++
.../fpu/finclude/math-vector-fortran.h | 2 +
sysdeps/aarch64/fpu/rsqrt_advsimd.c | 84 +++++++++++++++++++
sysdeps/aarch64/fpu/rsqrt_sve.c | 83 ++++++++++++++++++
sysdeps/aarch64/fpu/rsqrtf_advsimd.c | 82 ++++++++++++++++++
sysdeps/aarch64/fpu/rsqrtf_sve.c | 79 +++++++++++++++++
.../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 +
.../unix/sysv/linux/aarch64/libmvec.abilist | 5 ++
16 files changed, 366 insertions(+), 1 deletion(-)
create mode 100644 sysdeps/aarch64/fpu/rsqrt_advsimd.c
create mode 100644 sysdeps/aarch64/fpu/rsqrt_sve.c
create mode 100644 sysdeps/aarch64/fpu/rsqrtf_advsimd.c
create mode 100644 sysdeps/aarch64/fpu/rsqrtf_sve.c
diff --git a/bits/libm-simd-decl-stubs.h b/bits/libm-simd-decl-stubs.h
index 21e72917f7..e12936d7f7 100644
--- a/bits/libm-simd-decl-stubs.h
+++ b/bits/libm-simd-decl-stubs.h
@@ -242,6 +242,17 @@
#define __DECL_SIMD_atan2f64x
#define __DECL_SIMD_atan2f128x
+#define __DECL_SIMD_rsqrt
+#define __DECL_SIMD_rsqrtf
+#define __DECL_SIMD_rsqrtl
+#define __DECL_SIMD_rsqrtf16
+#define __DECL_SIMD_rsqrtf32
+#define __DECL_SIMD_rsqrtf64
+#define __DECL_SIMD_rsqrtf128
+#define __DECL_SIMD_rsqrtf32x
+#define __DECL_SIMD_rsqrtf64x
+#define __DECL_SIMD_rsqrtf128x
+
#define __DECL_SIMD_log10
#define __DECL_SIMD_log10f
#define __DECL_SIMD_log10l
diff --git a/math/bits/mathcalls.h b/math/bits/mathcalls.h
index 37149d8364..592a80fcb9 100644
--- a/math/bits/mathcalls.h
+++ b/math/bits/mathcalls.h
@@ -203,7 +203,7 @@ __MATHCALL (powr,, (_Mdouble_ __x, _Mdouble_ __y));
__MATHCALL (rootn,, (_Mdouble_ __x, long long int __y));
/* Return the reciprocal of the square root of X. */
-__MATHCALL (rsqrt,, (_Mdouble_ __x));
+__MATHCALL_VEC (rsqrt,, (_Mdouble_ __x));
#endif
diff --git a/sysdeps/aarch64/fpu/Makefile b/sysdeps/aarch64/fpu/Makefile
index df6cbe6b53..998fc08d43 100644
--- a/sysdeps/aarch64/fpu/Makefile
+++ b/sysdeps/aarch64/fpu/Makefile
@@ -29,6 +29,7 @@ libmvec-supported-funcs = acos \
log2 \
log2p1 \
pow \
+ rsqrt \
sin \
sinh \
sinpi \
diff --git a/sysdeps/aarch64/fpu/Versions b/sysdeps/aarch64/fpu/Versions
index c03de40fe1..d68510a20e 100644
--- a/sysdeps/aarch64/fpu/Versions
+++ b/sysdeps/aarch64/fpu/Versions
@@ -200,5 +200,10 @@ libmvec {
_ZGVnN4v_log10p1f;
_ZGVsMxv_log10p1;
_ZGVsMxv_log10p1f;
+ _ZGVnN2v_rsqrt;
+ _ZGVnN2v_rsqrtf;
+ _ZGVnN4v_rsqrtf;
+ _ZGVsMxv_rsqrt;
+ _ZGVsMxv_rsqrtf;
}
}
diff --git a/sysdeps/aarch64/fpu/advsimd_f32_protos.h b/sysdeps/aarch64/fpu/advsimd_f32_protos.h
index 77a902c11a..abdb1ff114 100644
--- a/sysdeps/aarch64/fpu/advsimd_f32_protos.h
+++ b/sysdeps/aarch64/fpu/advsimd_f32_protos.h
@@ -47,6 +47,7 @@ libmvec_hidden_proto (V_NAME_F1(log2p1));
libmvec_hidden_proto (V_NAME_F1(logp1));
libmvec_hidden_proto (V_NAME_F1(log));
libmvec_hidden_proto (V_NAME_F2(pow));
+libmvec_hidden_proto (V_NAME_F1(rsqrt));
libmvec_hidden_proto (V_NAME_F1(sin));
libmvec_hidden_proto (V_NAME_F1(sinh));
libmvec_hidden_proto (V_NAME_F1(sinpi));
diff --git a/sysdeps/aarch64/fpu/bits/math-vector.h b/sysdeps/aarch64/fpu/bits/math-vector.h
index 56b47f58ef..7406552f49 100644
--- a/sysdeps/aarch64/fpu/bits/math-vector.h
+++ b/sysdeps/aarch64/fpu/bits/math-vector.h
@@ -157,6 +157,10 @@
# define __DECL_SIMD_pow __DECL_SIMD_aarch64
# undef __DECL_SIMD_powf
# define __DECL_SIMD_powf __DECL_SIMD_aarch64
+# undef __DECL_SIMD_rsqrt
+# define __DECL_SIMD_rsqrt __DECL_SIMD_aarch64
+# undef __DECL_SIMD_rsqrtf
+# define __DECL_SIMD_rsqrtf __DECL_SIMD_aarch64
# undef __DECL_SIMD_sin
# define __DECL_SIMD_sin __DECL_SIMD_aarch64
# undef __DECL_SIMD_sinf
@@ -239,6 +243,7 @@ __vpcs __f32x4_t _ZGVnN4v_log2f (__f32x4_t);
__vpcs __f32x4_t _ZGVnN4v_log2p1f (__f32x4_t);
__vpcs __f32x4_t _ZGVnN4v_logp1f (__f32x4_t);
__vpcs __f32x4_t _ZGVnN4vv_powf (__f32x4_t, __f32x4_t);
+__vpcs __f32x4_t _ZGVnN4v_rsqrtf (__f32x4_t);
__vpcs __f32x4_t _ZGVnN4v_sinf (__f32x4_t);
__vpcs __f32x4_t _ZGVnN4v_sinhf (__f32x4_t);
__vpcs __f32x4_t _ZGVnN4v_sinpif (__f32x4_t);
@@ -278,6 +283,7 @@ __vpcs __f64x2_t _ZGVnN2v_log2 (__f64x2_t);
__vpcs __f64x2_t _ZGVnN2v_log2p1 (__f64x2_t);
__vpcs __f64x2_t _ZGVnN2v_logp1 (__f64x2_t);
__vpcs __f64x2_t _ZGVnN2vv_pow (__f64x2_t, __f64x2_t);
+__vpcs __f64x2_t _ZGVnN2v_rsqrt (__f64x2_t);
__vpcs __f64x2_t _ZGVnN2v_sin (__f64x2_t);
__vpcs __f64x2_t _ZGVnN2v_sinh (__f64x2_t);
__vpcs __f64x2_t _ZGVnN2v_sinpi (__f64x2_t);
@@ -322,6 +328,7 @@ __sv_f32_t _ZGVsMxv_log2f (__sv_f32_t, __sv_bool_t);
__sv_f32_t _ZGVsMxv_log2p1f (__sv_f32_t, __sv_bool_t);
__sv_f32_t _ZGVsMxv_logp1f (__sv_f32_t, __sv_bool_t);
__sv_f32_t _ZGVsMxvv_powf (__sv_f32_t, __sv_f32_t, __sv_bool_t);
+__sv_f32_t _ZGVsMxv_rsqrtf (__sv_f32_t, __sv_bool_t);
__sv_f32_t _ZGVsMxv_sinf (__sv_f32_t, __sv_bool_t);
__sv_f32_t _ZGVsMxv_sinhf (__sv_f32_t, __sv_bool_t);
__sv_f32_t _ZGVsMxv_sinpif (__sv_f32_t, __sv_bool_t);
@@ -361,6 +368,7 @@ __sv_f64_t _ZGVsMxv_log2 (__sv_f64_t, __sv_bool_t);
__sv_f64_t _ZGVsMxv_log2p1 (__sv_f64_t, __sv_bool_t);
__sv_f64_t _ZGVsMxv_logp1 (__sv_f64_t, __sv_bool_t);
__sv_f64_t _ZGVsMxvv_pow (__sv_f64_t, __sv_f64_t, __sv_bool_t);
+__sv_f64_t _ZGVsMxv_rsqrt (__sv_f64_t, __sv_bool_t);
__sv_f64_t _ZGVsMxv_sin (__sv_f64_t, __sv_bool_t);
__sv_f64_t _ZGVsMxv_sinh (__sv_f64_t, __sv_bool_t);
__sv_f64_t _ZGVsMxv_sinpi (__sv_f64_t, __sv_bool_t);
diff --git a/sysdeps/aarch64/fpu/finclude/math-vector-fortran.h b/sysdeps/aarch64/fpu/finclude/math-vector-fortran.h
index 0109687b5b..55e3469a2c 100644
--- a/sysdeps/aarch64/fpu/finclude/math-vector-fortran.h
+++ b/sysdeps/aarch64/fpu/finclude/math-vector-fortran.h
@@ -80,6 +80,8 @@
!GCC$ builtin (logp1f) attributes simd (notinbranch)
!GCC$ builtin (pow) attributes simd (notinbranch)
!GCC$ builtin (powf) attributes simd (notinbranch)
+!GCC$ builtin (rsqrt) attributes simd (notinbranch)
+!GCC$ builtin (rsqrtf) attributes simd (notinbranch)
!GCC$ builtin (sin) attributes simd (notinbranch)
!GCC$ builtin (sinf) attributes simd (notinbranch)
!GCC$ builtin (sinh) attributes simd (notinbranch)
diff --git a/sysdeps/aarch64/fpu/rsqrt_advsimd.c b/sysdeps/aarch64/fpu/rsqrt_advsimd.c
new file mode 100644
index 0000000000..f1504c6e5a
--- /dev/null
+++ b/sysdeps/aarch64/fpu/rsqrt_advsimd.c
@@ -0,0 +1,84 @@
+/* Double-precision vector (Advanced SIMD) rsqrt function
+
+ Copyright (C) 2025 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"
+
+static const struct data
+{
+ float64x2_t special_bound;
+ float64x2_t scale_up, scale_down;
+} data = {
+ /* When x < 0x1p-1021, estimate becomes infinity.
+ x is scaled up by 0x1p54, so the estimate does not reach infinity.
+ Then the result is multiplied by 0x1p27.
+ The difference between the lowest power possible (-1074) and the special
+ bound (-1021) is 54, so 2^54 is used as the scaling value. */
+ .special_bound = V2 (0x1p-1021),
+ .scale_up = V2 (0x1p54),
+ .scale_down = V2 (0x1p27),
+};
+
+static inline float64x2_t VPCS_ATTR
+inline_rsqrt (float64x2_t x)
+{
+ /* Do estimate instruction. */
+ float64x2_t estimate = vrsqrteq_f64 (x);
+
+ /* Do first step instruction. */
+ float64x2_t estimate_squared = vmulq_f64 (estimate, estimate);
+ float64x2_t step = vrsqrtsq_f64 (x, estimate_squared);
+ estimate = vmulq_f64 (estimate, step);
+
+ /* Do second step instruction. */
+ estimate_squared = vmulq_f64 (estimate, estimate);
+ step = vrsqrtsq_f64 (x, estimate_squared);
+ estimate = vmulq_f64 (estimate, step);
+
+ /* Do third step instruction.
+ This is required to achieve < 3.0 ULP. */
+ estimate_squared = vmulq_f64 (estimate, estimate);
+ step = vrsqrtsq_f64 (x, estimate_squared);
+ estimate = vmulq_f64 (estimate, step);
+ return estimate;
+}
+
+static float64x2_t NOINLINE
+special_case (float64x2_t x, uint64x2_t special, const struct data *d)
+{
+ x = vbslq_f64 (special, vmulq_f64 (x, d->scale_up), x);
+ float64x2_t estimate = inline_rsqrt (x);
+ return vbslq_f64 (special, vmulq_f64 (estimate, d->scale_down), estimate);
+}
+
+/* Double-precision implementation of vector rsqrt(x).
+ Maximum observed error: 1.45 + 0.5
+ _ZGVnN2v_rsqrt(0x1.d13fb41254643p+1023) got 0x1.0c8dee1b29dfap-512
+ want 0x1.0c8dee1b29df8p-512. */
+float64x2_t VPCS_ATTR V_NAME_D1 (rsqrt) (float64x2_t x)
+{
+ const struct data *d = ptr_barrier (&data);
+
+ /* Special case: x < special_bound. */
+ uint64x2_t special = vcgtq_f64 (d->special_bound, x);
+ if (__glibc_unlikely (v_any_u64 (special)))
+ {
+ return special_case (x, special, d);
+ }
+ return inline_rsqrt (x);
+}
diff --git a/sysdeps/aarch64/fpu/rsqrt_sve.c b/sysdeps/aarch64/fpu/rsqrt_sve.c
new file mode 100644
index 0000000000..6eda24f3db
--- /dev/null
+++ b/sysdeps/aarch64/fpu/rsqrt_sve.c
@@ -0,0 +1,83 @@
+/* Double-precision vector (SVE) rsqrt function
+
+ Copyright (C) 2025 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"
+
+static const struct data
+{
+ float64_t special_bound;
+ int64_t scale_up, scale_down;
+} data = {
+ /* When x < 0x1p-1021, estimate becomes infinity.
+ x is scaled up by 0x1p54, so the estimate does not reach infinity.
+ Then the result is multiplied by 0x1p27.
+ The difference between the lowest power possible (-1074) and the special
+ bound (-1021) is 54, so 2^54 is used as the scaling value. */
+ .special_bound = 0x1p-1021,
+ .scale_up = 54,
+ .scale_down = 27,
+};
+
+static inline svfloat64_t
+inline_rsqrt (svfloat64_t x)
+{
+ /* Do estimate instruction. */
+ svfloat64_t estimate = svrsqrte_f64 (x);
+
+ /* Do first step instruction. */
+ svfloat64_t estimate_squared = svmul_x (svptrue_b64 (), estimate, estimate);
+ svfloat64_t step = svrsqrts_f64 (x, estimate_squared);
+ estimate = svmul_x (svptrue_b64 (), estimate, step);
+
+ /* Do second step instruction. */
+ estimate_squared = svmul_x (svptrue_b64 (), estimate, estimate);
+ step = svrsqrts_f64 (x, estimate_squared);
+ estimate = svmul_x (svptrue_b64 (), estimate, step);
+
+ /* Do third step instruction.
+ This is required to achieve < 3.0 ULP. */
+ estimate_squared = svmul_x (svptrue_b64 (), estimate, estimate);
+ step = svrsqrts_f64 (x, estimate_squared);
+ estimate = svmul_x (svptrue_b64 (), estimate, step);
+ return estimate;
+}
+
+static svfloat64_t NOINLINE
+special_case (svfloat64_t x, svbool_t special, const struct data *d)
+{
+ x = svscale_f64_m (special, x, sv_s64 (d->scale_up));
+ svfloat64_t estimate = inline_rsqrt (x);
+ return svscale_f64_m (special, estimate, sv_s64 (d->scale_down));
+}
+
+/* Double-precision SVE implementation of rsqrt(x).
+ Maximum observed error: 1.45 + 0.5
+ _ZGVnN2v_rsqrt(0x1.d13fb41254643p+1023) got 0x1.0c8dee1b29dfap-512
+ want 0x1.0c8dee1b29df8p-512. */
+svfloat64_t SV_NAME_D1 (rsqrt) (svfloat64_t x, svbool_t pg)
+{
+ const struct data *d = ptr_barrier (&data);
+
+ svbool_t special = svcmplt_n_f64 (pg, x, d->special_bound);
+ if (__glibc_unlikely (svptest_any (pg, special)))
+ {
+ return special_case (x, special, d);
+ }
+ return inline_rsqrt (x);
+}
diff --git a/sysdeps/aarch64/fpu/rsqrtf_advsimd.c b/sysdeps/aarch64/fpu/rsqrtf_advsimd.c
new file mode 100644
index 0000000000..b65ed96681
--- /dev/null
+++ b/sysdeps/aarch64/fpu/rsqrtf_advsimd.c
@@ -0,0 +1,82 @@
+/* Single-precision vector (Advanced SIMD) rsqrt function
+
+ Copyright (C) 2025 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"
+
+static const struct data
+{
+ float32x4_t special_bound;
+ float32x4_t scale_up, scale_down;
+} data = {
+ /* When x < 0x1p-128, estimate becomes infinity.
+ x is scaled up by 0x1p22f, so estimate does not reach infinity.
+ Then the result is multiplied by 0x1p11f.
+ The difference between the lowest power possible (-149) and the special
+ bound (-128) is 21. 22 is used here so that a power of 2 can be used for
+ scaling in both directions. */
+ .special_bound = V4 (0x1p-128f),
+ .scale_up = V4 (0x1p22f),
+ .scale_down = V4 (0x1p11f),
+};
+
+static inline float32x4_t VPCS_ATTR
+inline_rsqrt (float32x4_t x)
+{
+ /* Do estimate instruction. */
+ float32x4_t estimate = vrsqrteq_f32 (x);
+
+ /* Do first step instruction. */
+ float32x4_t estimate_squared = vmulq_f32 (estimate, estimate);
+ float32x4_t step = vrsqrtsq_f32 (x, estimate_squared);
+ estimate = vmulq_f32 (estimate, step);
+
+ /* Do second step instruction.
+ This is required to achieve < 3.0 ULP. */
+ estimate_squared = vmulq_f32 (estimate, estimate);
+ step = vrsqrtsq_f32 (x, estimate_squared);
+ estimate = vmulq_f32 (estimate, step);
+ return estimate;
+}
+
+static float32x4_t NOINLINE
+special_case (float32x4_t x, uint32x4_t special, const struct data *d)
+{
+ x = vbslq_f32 (special, vmulq_f32 (x, d->scale_up), x);
+ float32x4_t estimate = inline_rsqrt (x);
+ return vbslq_f32 (special, vmulq_f32 (estimate, d->scale_down), estimate);
+}
+
+/* Single-precision implementation of vector rqsrtf(x).
+ Maximum observed error: 1.47 + 0.5
+ _ZGVnN4v_rsqrtf (0x1.f610dep+127) got 0x1.02852cp-64
+ want 0x1.02853p-64. */
+float32x4_t VPCS_ATTR NOINLINE V_NAME_F1 (rsqrt) (float32x4_t x)
+{
+ const struct data *d = ptr_barrier (&data);
+
+ /* Special case: x < special_bound. */
+ uint32x4_t special = vcgtq_f32 (d->special_bound, x);
+ if (__glibc_unlikely (v_any_u32 (special)))
+ {
+ return special_case (x, special, d);
+ }
+ return inline_rsqrt (x);
+}
+libmvec_hidden_def (V_NAME_F1 (rsqrt))
+HALF_WIDTH_ALIAS_F1 (rsqrt)
\ No newline at end of file
diff --git a/sysdeps/aarch64/fpu/rsqrtf_sve.c b/sysdeps/aarch64/fpu/rsqrtf_sve.c
new file mode 100644
index 0000000000..b752694e26
--- /dev/null
+++ b/sysdeps/aarch64/fpu/rsqrtf_sve.c
@@ -0,0 +1,79 @@
+/* Single-precision vector (SVE) rsqrt function
+
+ Copyright (C) 2025 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"
+
+static const struct data
+{
+ float32_t special_bound;
+ int32_t scale_up, scale_down;
+} data = {
+ /* When x < 0x1p-128, estimate becomes infinity.
+ x is scaled up by 0x1p22f, so estimate does not reach infinity.
+ Then the result is multiplied by 0x1p11f.
+ The difference between the lowest power possible (-149) and the special
+ bound (-128) is 21. 22 is used here so that a power of 2 can be used for
+ scaling in both directions. */
+ .special_bound = 0x1p-128f,
+ .scale_up = 22,
+ .scale_down = 11,
+};
+
+static inline svfloat32_t
+inline_rsqrt (svfloat32_t x)
+{
+ /* Do estimate instruction. */
+ svfloat32_t estimate = svrsqrte_f32 (x);
+
+ /* Do first step instruction. */
+ svfloat32_t estimate_squared = svmul_x (svptrue_b32 (), estimate, estimate);
+ svfloat32_t step = svrsqrts_f32 (x, estimate_squared);
+ estimate = svmul_x (svptrue_b32 (), estimate, step);
+
+ /* Do second step instruction.
+ This is required to achieve < 3.0 ULP. */
+ estimate_squared = svmul_x (svptrue_b32 (), estimate, estimate);
+ step = svrsqrts_f32 (x, estimate_squared);
+ estimate = svmul_x (svptrue_b32 (), estimate, step);
+ return estimate;
+}
+
+static svfloat32_t NOINLINE
+special_case (svfloat32_t x, svbool_t special, const struct data *d)
+{
+ x = svscale_f32_m (special, x, sv_s32 (d->scale_up));
+ svfloat32_t estimate = inline_rsqrt (x);
+ return svscale_f32_m (special, estimate, sv_s32 (d->scale_down));
+}
+
+/* Single-precision SVE implementation of rsqrtf(x).
+ Maximum observed error: 1.47 + 0.5
+ _ZGVsMxv_rsqrtf (0x1.f610dep+127) got 0x1.02852cp-64
+ want 0x1.02853p-64. */
+svfloat32_t SV_NAME_F1 (rsqrt) (svfloat32_t x, svbool_t pg)
+{
+ const struct data *d = ptr_barrier (&data);
+
+ svbool_t special = svcmplt_n_f32 (pg, x, 0x1p-128f);
+ if (__glibc_unlikely (svptest_any (pg, special)))
+ {
+ return special_case (x, special, d);
+ }
+ return inline_rsqrt (x);
+}
diff --git a/sysdeps/aarch64/fpu/test-double-advsimd-wrappers.c b/sysdeps/aarch64/fpu/test-double-advsimd-wrappers.c
index 8138f2f2a7..42d076b9a9 100644
--- a/sysdeps/aarch64/fpu/test-double-advsimd-wrappers.c
+++ b/sysdeps/aarch64/fpu/test-double-advsimd-wrappers.c
@@ -54,6 +54,7 @@ VPCS_VECTOR_WRAPPER (log1p_advsimd, _ZGVnN2v_log1p)
VPCS_VECTOR_WRAPPER (log2_advsimd, _ZGVnN2v_log2)
VPCS_VECTOR_WRAPPER (log2p1_advsimd, _ZGVnN2v_log2p1)
VPCS_VECTOR_WRAPPER_ff (pow_advsimd, _ZGVnN2vv_pow)
+VPCS_VECTOR_WRAPPER (rsqrt_advsimd, _ZGVnN2v_rsqrt)
VPCS_VECTOR_WRAPPER (sin_advsimd, _ZGVnN2v_sin)
VPCS_VECTOR_WRAPPER (sinh_advsimd, _ZGVnN2v_sinh)
VPCS_VECTOR_WRAPPER (sinpi_advsimd, _ZGVnN2v_sinpi)
diff --git a/sysdeps/aarch64/fpu/test-double-sve-wrappers.c b/sysdeps/aarch64/fpu/test-double-sve-wrappers.c
index 034098c1ec..543816558b 100644
--- a/sysdeps/aarch64/fpu/test-double-sve-wrappers.c
+++ b/sysdeps/aarch64/fpu/test-double-sve-wrappers.c
@@ -73,6 +73,7 @@ SVE_VECTOR_WRAPPER (log1p_sve, _ZGVsMxv_log1p)
SVE_VECTOR_WRAPPER (log2_sve, _ZGVsMxv_log2)
SVE_VECTOR_WRAPPER (log2p1_sve, _ZGVsMxv_log2p1)
SVE_VECTOR_WRAPPER_ff (pow_sve, _ZGVsMxvv_pow)
+SVE_VECTOR_WRAPPER (rsqrt_sve, _ZGVsMxv_rsqrt)
SVE_VECTOR_WRAPPER (sin_sve, _ZGVsMxv_sin)
SVE_VECTOR_WRAPPER (sinh_sve, _ZGVsMxv_sinh)
SVE_VECTOR_WRAPPER (sinpi_sve, _ZGVsMxv_sinpi)
diff --git a/sysdeps/aarch64/fpu/test-float-advsimd-wrappers.c b/sysdeps/aarch64/fpu/test-float-advsimd-wrappers.c
index 3879b3c654..5217709796 100644
--- a/sysdeps/aarch64/fpu/test-float-advsimd-wrappers.c
+++ b/sysdeps/aarch64/fpu/test-float-advsimd-wrappers.c
@@ -54,6 +54,7 @@ VPCS_VECTOR_WRAPPER (log1pf_advsimd, _ZGVnN4v_log1pf)
VPCS_VECTOR_WRAPPER (log2f_advsimd, _ZGVnN4v_log2f)
VPCS_VECTOR_WRAPPER (log2p1f_advsimd, _ZGVnN4v_log2p1f)
VPCS_VECTOR_WRAPPER_ff (powf_advsimd, _ZGVnN4vv_powf)
+VPCS_VECTOR_WRAPPER (rsqrtf_advsimd, _ZGVnN4v_rsqrtf)
VPCS_VECTOR_WRAPPER (sinf_advsimd, _ZGVnN4v_sinf)
VPCS_VECTOR_WRAPPER (sinhf_advsimd, _ZGVnN4v_sinhf)
VPCS_VECTOR_WRAPPER (sinpif_advsimd, _ZGVnN4v_sinpif)
diff --git a/sysdeps/aarch64/fpu/test-float-sve-wrappers.c b/sysdeps/aarch64/fpu/test-float-sve-wrappers.c
index 38a6e03c23..a35b2fc7b5 100644
--- a/sysdeps/aarch64/fpu/test-float-sve-wrappers.c
+++ b/sysdeps/aarch64/fpu/test-float-sve-wrappers.c
@@ -73,6 +73,7 @@ SVE_VECTOR_WRAPPER (log1pf_sve, _ZGVsMxv_log1pf)
SVE_VECTOR_WRAPPER (log2f_sve, _ZGVsMxv_log2f)
SVE_VECTOR_WRAPPER (log2p1f_sve, _ZGVsMxv_log2p1f)
SVE_VECTOR_WRAPPER_ff (powf_sve, _ZGVsMxvv_powf)
+SVE_VECTOR_WRAPPER (rsqrtf_sve, _ZGVsMxv_rsqrtf)
SVE_VECTOR_WRAPPER (sinf_sve, _ZGVsMxv_sinf)
SVE_VECTOR_WRAPPER (sinhf_sve, _ZGVsMxv_sinhf)
SVE_VECTOR_WRAPPER (sinpif_sve, _ZGVsMxv_sinpif)
diff --git a/sysdeps/unix/sysv/linux/aarch64/libmvec.abilist b/sysdeps/unix/sysv/linux/aarch64/libmvec.abilist
index fb2eec79a5..6d13d53613 100644
--- a/sysdeps/unix/sysv/linux/aarch64/libmvec.abilist
+++ b/sysdeps/unix/sysv/linux/aarch64/libmvec.abilist
@@ -176,10 +176,13 @@ GLIBC_2.43 _ZGVnN2v_log10p1 F
GLIBC_2.43 _ZGVnN2v_log10p1f F
GLIBC_2.43 _ZGVnN2v_log2p1 F
GLIBC_2.43 _ZGVnN2v_log2p1f F
+GLIBC_2.43 _ZGVnN2v_rsqrt F
+GLIBC_2.43 _ZGVnN2v_rsqrtf F
GLIBC_2.43 _ZGVnN4v_exp10m1f F
GLIBC_2.43 _ZGVnN4v_exp2m1f F
GLIBC_2.43 _ZGVnN4v_log10p1f F
GLIBC_2.43 _ZGVnN4v_log2p1f F
+GLIBC_2.43 _ZGVnN4v_rsqrtf F
GLIBC_2.43 _ZGVsMxv_exp10m1 F
GLIBC_2.43 _ZGVsMxv_exp10m1f F
GLIBC_2.43 _ZGVsMxv_exp2m1 F
@@ -188,3 +191,5 @@ GLIBC_2.43 _ZGVsMxv_log10p1 F
GLIBC_2.43 _ZGVsMxv_log10p1f F
GLIBC_2.43 _ZGVsMxv_log2p1 F
GLIBC_2.43 _ZGVsMxv_log2p1f F
+GLIBC_2.43 _ZGVsMxv_rsqrt F
+GLIBC_2.43 _ZGVsMxv_rsqrtf F
--
2.34.1
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