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Diffstat (limited to 'pl/math/sv_exp10f_1u5.c')
-rw-r--r--pl/math/sv_exp10f_1u5.c87
1 files changed, 0 insertions, 87 deletions
diff --git a/pl/math/sv_exp10f_1u5.c b/pl/math/sv_exp10f_1u5.c
deleted file mode 100644
index 9ecde8f1aa52..000000000000
--- a/pl/math/sv_exp10f_1u5.c
+++ /dev/null
@@ -1,87 +0,0 @@
-/*
- * Single-precision SVE 2^x function.
- *
- * Copyright (c) 2023, Arm Limited.
- * SPDX-License-Identifier: MIT OR Apache-2.0 WITH LLVM-exception
- */
-
-#include "sv_math.h"
-#include "include/mathlib.h"
-#include "pl_sig.h"
-#include "pl_test.h"
-#include "poly_sve_f32.h"
-
-/* For x < -SpecialBound, the result is subnormal and not handled correctly by
- FEXPA. */
-#define SpecialBound 37.9
-
-static const struct data
-{
- float poly[5];
- float shift, log10_2, log2_10_hi, log2_10_lo, special_bound;
-} data = {
- /* Coefficients generated using Remez algorithm with minimisation of relative
- error.
- rel error: 0x1.89dafa3p-24
- abs error: 0x1.167d55p-23 in [-log10(2)/2, log10(2)/2]
- maxerr: 0.52 +0.5 ulp. */
- .poly = { 0x1.26bb16p+1f, 0x1.5350d2p+1f, 0x1.04744ap+1f, 0x1.2d8176p+0f,
- 0x1.12b41ap-1f },
- /* 1.5*2^17 + 127, a shift value suitable for FEXPA. */
- .shift = 0x1.903f8p17f,
- .log10_2 = 0x1.a934fp+1,
- .log2_10_hi = 0x1.344136p-2,
- .log2_10_lo = -0x1.ec10cp-27,
- .special_bound = SpecialBound,
-};
-
-static svfloat32_t NOINLINE
-special_case (svfloat32_t x, svfloat32_t y, svbool_t special)
-{
- return sv_call_f32 (exp10f, x, y, special);
-}
-
-/* Single-precision SVE exp10f routine. Implements the same algorithm
- as AdvSIMD exp10f.
- Worst case error is 1.02 ULPs.
- _ZGVsMxv_exp10f(-0x1.040488p-4) got 0x1.ba5f9ep-1
- want 0x1.ba5f9cp-1. */
-svfloat32_t SV_NAME_F1 (exp10) (svfloat32_t x, const svbool_t pg)
-{
- const struct data *d = ptr_barrier (&data);
- /* exp10(x) = 2^(n/N) * 10^r = 2^n * (1 + poly (r)),
- with poly(r) in [1/sqrt(2), sqrt(2)] and
- x = r + n * log10(2) / N, with r in [-log10(2)/2N, log10(2)/2N]. */
-
- /* Load some constants in quad-word chunks to minimise memory access (last
- lane is wasted). */
- svfloat32_t log10_2_and_inv = svld1rq (svptrue_b32 (), &d->log10_2);
-
- /* n = round(x/(log10(2)/N)). */
- svfloat32_t shift = sv_f32 (d->shift);
- svfloat32_t z = svmla_lane (shift, x, log10_2_and_inv, 0);
- svfloat32_t n = svsub_x (pg, z, shift);
-
- /* r = x - n*log10(2)/N. */
- svfloat32_t r = svmls_lane (x, n, log10_2_and_inv, 1);
- r = svmls_lane (r, n, log10_2_and_inv, 2);
-
- svbool_t special = svacgt (pg, x, d->special_bound);
- svfloat32_t scale = svexpa (svreinterpret_u32 (z));
-
- /* Polynomial evaluation: poly(r) ~ exp10(r)-1. */
- svfloat32_t r2 = svmul_x (pg, r, r);
- svfloat32_t poly
- = svmla_x (pg, svmul_x (pg, r, d->poly[0]),
- sv_pairwise_poly_3_f32_x (pg, r, r2, d->poly + 1), r2);
-
- if (unlikely (svptest_any (pg, special)))
- return special_case (x, svmla_x (pg, scale, scale, poly), special);
-
- return svmla_x (pg, scale, scale, poly);
-}
-
-PL_SIG (SV, F, 1, exp10, -9.9, 9.9)
-PL_TEST_ULP (SV_NAME_F1 (exp10), 0.52)
-PL_TEST_SYM_INTERVAL (SV_NAME_F1 (exp10), 0, SpecialBound, 50000)
-PL_TEST_SYM_INTERVAL (SV_NAME_F1 (exp10), SpecialBound, inf, 50000)