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-rw-r--r--pl/math/sv_acosf_1u4.c84
1 files changed, 0 insertions, 84 deletions
diff --git a/pl/math/sv_acosf_1u4.c b/pl/math/sv_acosf_1u4.c
deleted file mode 100644
index 7ac59ceedfbd..000000000000
--- a/pl/math/sv_acosf_1u4.c
+++ /dev/null
@@ -1,84 +0,0 @@
-/*
- * Single-precision SVE acos(x) function.
- *
- * Copyright (c) 2023, Arm Limited.
- * SPDX-License-Identifier: MIT OR Apache-2.0 WITH LLVM-exception
- */
-
-#include "sv_math.h"
-#include "poly_sve_f32.h"
-#include "pl_sig.h"
-#include "pl_test.h"
-
-static const struct data
-{
- float32_t poly[5];
- float32_t pi, pi_over_2;
-} data = {
- /* Polynomial approximation of (asin(sqrt(x)) - sqrt(x)) / (x * sqrt(x)) on
- [ 0x1p-24 0x1p-2 ] order = 4 rel error: 0x1.00a23bbp-29 . */
- .poly = { 0x1.55555ep-3, 0x1.33261ap-4, 0x1.70d7dcp-5, 0x1.b059dp-6,
- 0x1.3af7d8p-5, },
- .pi = 0x1.921fb6p+1f,
- .pi_over_2 = 0x1.921fb6p+0f,
-};
-
-/* Single-precision SVE implementation of vector acos(x).
-
- For |x| in [0, 0.5], use order 4 polynomial P such that the final
- approximation of asin is an odd polynomial:
-
- acos(x) ~ pi/2 - (x + x^3 P(x^2)).
-
- The largest observed error in this region is 1.16 ulps,
- _ZGVsMxv_acosf(0x1.ffbeccp-2) got 0x1.0c27f8p+0
- want 0x1.0c27f6p+0.
-
- For |x| in [0.5, 1.0], use same approximation with a change of variable
-
- acos(x) = y + y * z * P(z), with z = (1-x)/2 and y = sqrt(z).
-
- The largest observed error in this region is 1.32 ulps,
- _ZGVsMxv_acosf (0x1.15ba56p-1) got 0x1.feb33p-1
- want 0x1.feb32ep-1. */
-svfloat32_t SV_NAME_F1 (acos) (svfloat32_t x, const svbool_t pg)
-{
- const struct data *d = ptr_barrier (&data);
-
- svuint32_t sign = svand_x (pg, svreinterpret_u32 (x), 0x80000000);
- svfloat32_t ax = svabs_x (pg, x);
- svbool_t a_gt_half = svacgt (pg, x, 0.5);
-
- /* Evaluate polynomial Q(x) = z + z * z2 * P(z2) with
- z2 = x ^ 2 and z = |x| , if |x| < 0.5
- z2 = (1 - |x|) / 2 and z = sqrt(z2), if |x| >= 0.5. */
- svfloat32_t z2 = svsel (a_gt_half, svmls_x (pg, sv_f32 (0.5), ax, 0.5),
- svmul_x (pg, x, x));
- svfloat32_t z = svsqrt_m (ax, a_gt_half, z2);
-
- /* Use a single polynomial approximation P for both intervals. */
- svfloat32_t p = sv_horner_4_f32_x (pg, z2, d->poly);
- /* Finalize polynomial: z + z * z2 * P(z2). */
- p = svmla_x (pg, z, svmul_x (pg, z, z2), p);
-
- /* acos(|x|) = pi/2 - sign(x) * Q(|x|), for |x| < 0.5
- = 2 Q(|x|) , for 0.5 < x < 1.0
- = pi - 2 Q(|x|) , for -1.0 < x < -0.5. */
- svfloat32_t y
- = svreinterpret_f32 (svorr_x (pg, svreinterpret_u32 (p), sign));
-
- svbool_t is_neg = svcmplt (pg, x, 0.0);
- svfloat32_t off = svdup_f32_z (is_neg, d->pi);
- svfloat32_t mul = svsel (a_gt_half, sv_f32 (2.0), sv_f32 (-1.0));
- svfloat32_t add = svsel (a_gt_half, off, sv_f32 (d->pi_over_2));
-
- return svmla_x (pg, add, mul, y);
-}
-
-PL_SIG (SV, F, 1, acos, -1.0, 1.0)
-PL_TEST_ULP (SV_NAME_F1 (acos), 0.82)
-PL_TEST_INTERVAL (SV_NAME_F1 (acos), 0, 0.5, 50000)
-PL_TEST_INTERVAL (SV_NAME_F1 (acos), 0.5, 1.0, 50000)
-PL_TEST_INTERVAL (SV_NAME_F1 (acos), 1.0, 0x1p11, 50000)
-PL_TEST_INTERVAL (SV_NAME_F1 (acos), 0x1p11, inf, 20000)
-PL_TEST_INTERVAL (SV_NAME_F1 (acos), -0, -inf, 20000)