diff options
Diffstat (limited to 'pl/math/sv_tanf_3u5.c')
| -rw-r--r-- | pl/math/sv_tanf_3u5.c | 119 |
1 files changed, 0 insertions, 119 deletions
diff --git a/pl/math/sv_tanf_3u5.c b/pl/math/sv_tanf_3u5.c deleted file mode 100644 index 6b8cd1e64b44..000000000000 --- a/pl/math/sv_tanf_3u5.c +++ /dev/null @@ -1,119 +0,0 @@ -/* - * Single-precision vector tan(x) function. - * - * Copyright (c) 2020-2023, Arm Limited. - * SPDX-License-Identifier: MIT OR Apache-2.0 WITH LLVM-exception - */ - -#include "sv_math.h" -#include "pl_sig.h" -#include "pl_test.h" - -static const struct data -{ - float pio2_1, pio2_2, pio2_3, invpio2; - float c1, c3, c5; - float c0, c2, c4, range_val, shift; -} data = { - /* Coefficients generated using: - poly = fpminimax((tan(sqrt(x))-sqrt(x))/x^(3/2), - deg, - [|single ...|], - [a*a;b*b]); - optimize relative error - final prec : 23 bits - deg : 5 - a : 0x1p-126 ^ 2 - b : ((pi) / 0x1p2) ^ 2 - dirty rel error: 0x1.f7c2e4p-25 - dirty abs error: 0x1.f7c2ecp-25. */ - .c0 = 0x1.55555p-2, .c1 = 0x1.11166p-3, - .c2 = 0x1.b88a78p-5, .c3 = 0x1.7b5756p-6, - .c4 = 0x1.4ef4cep-8, .c5 = 0x1.0e1e74p-7, - - .pio2_1 = 0x1.921fb6p+0f, .pio2_2 = -0x1.777a5cp-25f, - .pio2_3 = -0x1.ee59dap-50f, .invpio2 = 0x1.45f306p-1f, - .range_val = 0x1p15f, .shift = 0x1.8p+23f -}; - -static svfloat32_t NOINLINE -special_case (svfloat32_t x, svfloat32_t y, svbool_t cmp) -{ - return sv_call_f32 (tanf, x, y, cmp); -} - -/* Fast implementation of SVE tanf. - Maximum error is 3.45 ULP: - SV_NAME_F1 (tan)(-0x1.e5f0cap+13) got 0x1.ff9856p-1 - want 0x1.ff9850p-1. */ -svfloat32_t SV_NAME_F1 (tan) (svfloat32_t x, const svbool_t pg) -{ - const struct data *d = ptr_barrier (&data); - - /* Determine whether input is too large to perform fast regression. */ - svbool_t cmp = svacge (pg, x, d->range_val); - - svfloat32_t odd_coeffs = svld1rq (svptrue_b32 (), &d->c1); - svfloat32_t pi_vals = svld1rq (svptrue_b32 (), &d->pio2_1); - - /* n = rint(x/(pi/2)). */ - svfloat32_t q = svmla_lane (sv_f32 (d->shift), x, pi_vals, 3); - svfloat32_t n = svsub_x (pg, q, d->shift); - /* n is already a signed integer, simply convert it. */ - svint32_t in = svcvt_s32_x (pg, n); - /* Determine if x lives in an interval, where |tan(x)| grows to infinity. */ - svint32_t alt = svand_x (pg, in, 1); - svbool_t pred_alt = svcmpne (pg, alt, 0); - - /* r = x - n * (pi/2) (range reduction into 0 .. pi/4). */ - svfloat32_t r; - r = svmls_lane (x, n, pi_vals, 0); - r = svmls_lane (r, n, pi_vals, 1); - r = svmls_lane (r, n, pi_vals, 2); - - /* If x lives in an interval, where |tan(x)| - - is finite, then use a polynomial approximation of the form - tan(r) ~ r + r^3 * P(r^2) = r + r * r^2 * P(r^2). - - grows to infinity then use symmetries of tangent and the identity - tan(r) = cotan(pi/2 - r) to express tan(x) as 1/tan(-r). Finally, use - the same polynomial approximation of tan as above. */ - - /* Perform additional reduction if required. */ - svfloat32_t z = svneg_m (r, pred_alt, r); - - /* Evaluate polynomial approximation of tangent on [-pi/4, pi/4], - using Estrin on z^2. */ - svfloat32_t z2 = svmul_x (pg, z, z); - svfloat32_t p01 = svmla_lane (sv_f32 (d->c0), z2, odd_coeffs, 0); - svfloat32_t p23 = svmla_lane (sv_f32 (d->c2), z2, odd_coeffs, 1); - svfloat32_t p45 = svmla_lane (sv_f32 (d->c4), z2, odd_coeffs, 2); - - svfloat32_t z4 = svmul_x (pg, z2, z2); - svfloat32_t p = svmla_x (pg, p01, z4, p23); - - svfloat32_t z8 = svmul_x (pg, z4, z4); - p = svmla_x (pg, p, z8, p45); - - svfloat32_t y = svmla_x (pg, z, p, svmul_x (pg, z, z2)); - - /* Transform result back, if necessary. */ - svfloat32_t inv_y = svdivr_x (pg, y, 1.0f); - - /* No need to pass pg to specialcase here since cmp is a strict subset, - guaranteed by the cmpge above. */ - if (unlikely (svptest_any (pg, cmp))) - return special_case (x, svsel (pred_alt, inv_y, y), cmp); - - return svsel (pred_alt, inv_y, y); -} - -PL_SIG (SV, F, 1, tan, -3.1, 3.1) -PL_TEST_ULP (SV_NAME_F1 (tan), 2.96) -PL_TEST_INTERVAL (SV_NAME_F1 (tan), -0.0, -0x1p126, 100) -PL_TEST_INTERVAL (SV_NAME_F1 (tan), 0x1p-149, 0x1p-126, 4000) -PL_TEST_INTERVAL (SV_NAME_F1 (tan), 0x1p-126, 0x1p-23, 50000) -PL_TEST_INTERVAL (SV_NAME_F1 (tan), 0x1p-23, 0.7, 50000) -PL_TEST_INTERVAL (SV_NAME_F1 (tan), 0.7, 1.5, 50000) -PL_TEST_INTERVAL (SV_NAME_F1 (tan), 1.5, 100, 50000) -PL_TEST_INTERVAL (SV_NAME_F1 (tan), 100, 0x1p17, 50000) -PL_TEST_INTERVAL (SV_NAME_F1 (tan), 0x1p17, inf, 50000) |