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Diffstat (limited to 'pl/math/sv_erfcf_1u7.c')
-rw-r--r--pl/math/sv_erfcf_1u7.c111
1 files changed, 0 insertions, 111 deletions
diff --git a/pl/math/sv_erfcf_1u7.c b/pl/math/sv_erfcf_1u7.c
deleted file mode 100644
index cda8f0b3752e..000000000000
--- a/pl/math/sv_erfcf_1u7.c
+++ /dev/null
@@ -1,111 +0,0 @@
-/*
- * Single-precision vector erfc(x) function.
- *
- * Copyright (c) 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
-{
- uint32_t off_idx, off_arr;
- float max, shift;
- float third, two_thirds, two_over_fifteen, two_over_five, tenth;
-} data = {
- /* Set an offset so the range of the index used for lookup is 644, and it can
- be clamped using a saturated add. */
- .off_idx = 0xb7fffd7b, /* 0xffffffff - asuint(shift) - 644. */
- .off_arr = 0xfffffd7b, /* 0xffffffff - 644. */
- .max = 10.0625f, /* 644/64. */
- .shift = 0x1p17f,
- .third = 0x1.555556p-2f,
- .two_thirds = 0x1.555556p-1f,
- .two_over_fifteen = 0x1.111112p-3f,
- .two_over_five = -0x1.99999ap-2f,
- .tenth = -0x1.99999ap-4f,
-};
-
-#define SignMask 0x80000000
-#define TableScale 0x28000000 /* 0x1p-47. */
-
-/* Optimized single-precision vector erfcf(x).
- Approximation based on series expansion near x rounded to
- nearest multiple of 1/64.
- Let d = x - r, and scale = 2 / sqrt(pi) * exp(-r^2). For x near r,
-
- erfc(x) ~ erfc(r) - scale * d * poly(r, d), with
-
- poly(r, d) = 1 - r d + (2/3 r^2 - 1/3) d^2 - r (1/3 r^2 - 1/2) d^3
- + (2/15 r^4 - 2/5 r^2 + 1/10) d^4
-
- Values of erfc(r) and scale are read from lookup tables. Stored values
- are scaled to avoid hitting the subnormal range.
-
- Note that for x < 0, erfc(x) = 2.0 - erfc(-x).
-
- Maximum error: 1.63 ULP (~1.0 ULP for x < 0.0).
- _ZGVsMxv_erfcf(0x1.1dbf7ap+3) got 0x1.f51212p-120
- want 0x1.f51216p-120. */
-svfloat32_t SV_NAME_F1 (erfc) (svfloat32_t x, const svbool_t pg)
-{
- const struct data *dat = ptr_barrier (&data);
-
- svfloat32_t a = svabs_x (pg, x);
-
- /* Clamp input at |x| <= 10.0 + 4/64. */
- a = svmin_x (pg, a, dat->max);
-
- /* Reduce x to the nearest multiple of 1/64. */
- svfloat32_t shift = sv_f32 (dat->shift);
- svfloat32_t z = svadd_x (pg, a, shift);
-
- /* Saturate index for the NaN case. */
- svuint32_t i = svqadd (svreinterpret_u32 (z), dat->off_idx);
-
- /* Lookup erfc(r) and 2/sqrt(pi)*exp(-r^2) in tables. */
- i = svmul_x (pg, i, 2);
- const float32_t *p = &__erfcf_data.tab[0].erfc - 2 * dat->off_arr;
- svfloat32_t erfcr = svld1_gather_index (pg, p, i);
- svfloat32_t scale = svld1_gather_index (pg, p + 1, i);
-
- /* erfc(x) ~ erfc(r) - scale * d * poly(r, d). */
- svfloat32_t r = svsub_x (pg, z, shift);
- svfloat32_t d = svsub_x (pg, a, r);
- svfloat32_t d2 = svmul_x (pg, d, d);
- svfloat32_t r2 = svmul_x (pg, r, r);
-
- svfloat32_t coeffs = svld1rq (svptrue_b32 (), &dat->third);
- svfloat32_t third = svdup_lane (coeffs, 0);
-
- svfloat32_t p1 = r;
- svfloat32_t p2 = svmls_lane (third, r2, coeffs, 1);
- svfloat32_t p3 = svmul_x (pg, r, svmla_lane (sv_f32 (-0.5), r2, coeffs, 0));
- svfloat32_t p4 = svmla_lane (sv_f32 (dat->two_over_five), r2, coeffs, 2);
- p4 = svmls_x (pg, sv_f32 (dat->tenth), r2, p4);
-
- svfloat32_t y = svmla_x (pg, p3, d, p4);
- y = svmla_x (pg, p2, d, y);
- y = svmla_x (pg, p1, d, y);
-
- /* Solves the |x| = inf/nan case. */
- y = svmls_x (pg, erfcr, scale, svmls_x (pg, d, d2, y));
-
- /* Offset equals 2.0f if sign, else 0.0f. */
- svuint32_t sign = svand_x (pg, svreinterpret_u32 (x), SignMask);
- svfloat32_t off = svreinterpret_f32 (svlsr_x (pg, sign, 1));
- /* Handle sign and scale back in a single fma. */
- svfloat32_t fac = svreinterpret_f32 (svorr_x (pg, sign, TableScale));
-
- return svmla_x (pg, off, fac, y);
-}
-
-PL_SIG (SV, F, 1, erfc, -4.0, 10.0)
-PL_TEST_ULP (SV_NAME_F1 (erfc), 1.14)
-PL_TEST_SYM_INTERVAL (SV_NAME_F1 (erfc), 0.0, 0x1p-26, 40000)
-PL_TEST_INTERVAL (SV_NAME_F1 (erfc), 0x1p-26, 10.0625, 40000)
-PL_TEST_INTERVAL (SV_NAME_F1 (erfc), -0x1p-26, -4.0, 40000)
-PL_TEST_INTERVAL (SV_NAME_F1 (erfc), 10.0625, inf, 40000)
-PL_TEST_INTERVAL (SV_NAME_F1 (erfc), -4.0, -inf, 40000)