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Diffstat (limited to 'pl/math/v_erfcf_1u.c')
| -rw-r--r-- | pl/math/v_erfcf_1u.c | 183 |
1 files changed, 0 insertions, 183 deletions
diff --git a/pl/math/v_erfcf_1u.c b/pl/math/v_erfcf_1u.c deleted file mode 100644 index 963490d789bd..000000000000 --- a/pl/math/v_erfcf_1u.c +++ /dev/null @@ -1,183 +0,0 @@ -/* - * Single-precision vector erfc(x) function. - * - * Copyright (c) 2021-2023, Arm Limited. - * SPDX-License-Identifier: MIT OR Apache-2.0 WITH LLVM-exception - */ - -#include "v_math.h" -#include "erfcf.h" -#include "estrin.h" -#include "pl_sig.h" -#include "pl_test.h" - -#if V_SUPPORTED - -#define P(ia12) __erfcf_poly_data.poly[interval_index (ia12)] - -VPCS_ATTR v_f64_t V_NAME (exp_tail) (v_f64_t, v_f64_t); - -static VPCS_ATTR NOINLINE v_f32_t -specialcase (v_f32_t x, v_f32_t y, v_u32_t special) -{ - return v_call_f32 (erfcf, x, y, special); -} - -static inline uint32_t -interval_index (uint32_t ia12) -{ - // clang-format off - return (ia12 < 0x400 ? 0 : - (ia12 < 0x408 ? 1 : - (ia12 < 0x410 ? 2 : - 3))); - // clang-format on -} - -/* The C macro wraps the coeffs argument in order to make the - poynomial evaluation more readable. In the scalarised variant the - second pointer is ignored. */ -#ifdef SCALAR -#define C(i) coeff1[i] -#else -#define C(i) ((v_f64_t){coeff1[i], coeff2[i]}) -#endif - -static inline v_f64_t -v_approx_erfcf_poly_gauss (v_f64_t x, const double *coeff1, - const double *coeff2) -{ - v_f64_t x2 = x * x; - v_f64_t x4 = x2 * x2; - v_f64_t poly = ESTRIN_15 (x, x2, x4, x4 * x4, C); - v_f64_t gauss = V_NAME (exp_tail) (-(x * x), v_f64 (0.0)); - return poly * gauss; -} - -static inline float -approx_poly_gauss (float abs_x, const double *coeff) -{ - return (float) (eval_poly (abs_x, coeff) * eval_exp_mx2 (abs_x)); -} - -static v_f32_t -v_approx_erfcf (v_f32_t abs_x, v_u32_t sign, v_u32_t ia12, v_u32_t lanes) -{ -#ifdef SCALAR - float y = approx_poly_gauss (abs_x, P (ia12)); - return sign ? 2 - y : y; -#else - float32x2_t lo32 = {0, 0}; - float32x2_t hi32 = {0, 0}; - /* The polynomial and Gaussian components must be calculated in - double precision in order to meet the required ULP error. This - means we have to promote low and high halves of the - single-precision input vector to two separate double-precision - input vectors. This incurs some overhead, and there is also - overhead to loading the polynomial coefficients as this cannot be - done in a vector fashion. This would be wasted effort for - elements which lie in the 'boring' zone, as they will be - overwritten later. Hence we use the lanes parameter to only do - the promotion on a pair of lanes if both of those lanes are - interesting and not special cases. If one lane is inactive, we - use a scalar routine which is shared with the scalar variant. */ - if (lanes[0] & lanes[1]) - { - lo32 = vcvt_f32_f64 ( - v_approx_erfcf_poly_gauss (vcvt_f64_f32 (vget_low_f32 (abs_x)), - P (ia12[0]), P (ia12[1]))); - } - else if (lanes[0]) - { - lo32[0] = approx_poly_gauss (abs_x[0], P (ia12[0])); - } - else if (lanes[1]) - { - lo32[1] = approx_poly_gauss (abs_x[1], P (ia12[1])); - } - - if (lanes[2] & lanes[3]) - { - hi32 - = vcvt_f32_f64 (v_approx_erfcf_poly_gauss (vcvt_high_f64_f32 (abs_x), - P (ia12[2]), P (ia12[3]))); - } - else if (lanes[2]) - { - hi32[0] = approx_poly_gauss (abs_x[2], P (ia12[2])); - } - else if (lanes[3]) - { - hi32[1] = approx_poly_gauss (abs_x[3], P (ia12[3])); - } - - v_f32_t y = vcombine_f32 (lo32, hi32); - - if (v_any_u32 (sign)) - { - y = vbslq_f32 (vceqzq_u32 (sign), y, 2 - y); - } - - return y; -#endif -} - -/* Optimized single-precision vector complementary error function - erfcf. Max measured error: 0.750092 at various values between - -0x1.06521p-20 and -0x1.add1dap-17. For example: - __v_erfc(-0x1.08185p-18) got 0x1.00004cp+0 want 0x1.00004ap+0 - +0.249908 ulp err 0.250092. */ -VPCS_ATTR -v_f32_t V_NAME (erfcf) (v_f32_t x) -{ - v_u32_t ix = v_as_u32_f32 (x); - v_u32_t ia = ix & 0x7fffffff; - v_u32_t ia12 = ia >> 20; - v_u32_t sign = ix >> 31; - v_u32_t inf_ia12 = v_u32 (0x7f8); - - v_u32_t special_cases - = v_cond_u32 ((ia12 - 0x328) >= ((inf_ia12 & 0x7f8) - 0x328)); - v_u32_t in_bounds - = v_cond_u32 ((ia < 0x408ccccd) | (~sign & (ix < 0x4120f5c3))); - v_f32_t boring_zone = v_as_f32_u32 (sign << 30); - -#ifdef SCALAR - if (unlikely (special_cases)) - { - if (ia12 >= 0x7f8) - return (float) (sign << 1) + 1.0f / x; /* Special cases. */ - else - return 1.0f - x; /* Small case. */ - } - else if (likely (!in_bounds)) - { - return sign ? boring_zone : __math_uflowf (boring_zone); - } -#endif - - v_f32_t y = v_approx_erfcf (v_as_f32_u32 (ia), sign, ia12, - in_bounds & ~special_cases); - -#ifndef SCALAR - y = vbslq_f32 (~in_bounds, boring_zone, y); - - if (unlikely (v_any_u32 (special_cases))) - { - return specialcase (x, y, special_cases); - } -#endif - - return y; -} -VPCS_ALIAS - -PL_SIG (V, F, 1, erfc, -6.0, 28.0) -PL_TEST_ULP (V_NAME (erfcf), 0.26) -PL_TEST_INTERVAL (V_NAME (erfcf), 0, 0xffff0000, 10000) -PL_TEST_INTERVAL (V_NAME (erfcf), 0x1p-127, 0x1p-26, 40000) -PL_TEST_INTERVAL (V_NAME (erfcf), -0x1p-127, -0x1p-26, 40000) -PL_TEST_INTERVAL (V_NAME (erfcf), 0x1p-26, 0x1p5, 40000) -PL_TEST_INTERVAL (V_NAME (erfcf), -0x1p-26, -0x1p3, 40000) -PL_TEST_INTERVAL (V_NAME (erfcf), 0, inf, 40000) -#endif |