diff options
Diffstat (limited to 'pl/math/v_atan2_3u.c')
| -rw-r--r-- | pl/math/v_atan2_3u.c | 121 |
1 files changed, 0 insertions, 121 deletions
diff --git a/pl/math/v_atan2_3u.c b/pl/math/v_atan2_3u.c deleted file mode 100644 index f24667682dec..000000000000 --- a/pl/math/v_atan2_3u.c +++ /dev/null @@ -1,121 +0,0 @@ -/* - * Double-precision vector atan2(x) function. - * - * Copyright (c) 2021-2023, Arm Limited. - * SPDX-License-Identifier: MIT OR Apache-2.0 WITH LLVM-exception - */ - -#include "v_math.h" -#include "pl_sig.h" -#include "pl_test.h" -#include "poly_advsimd_f64.h" - -static const struct data -{ - float64x2_t pi_over_2; - float64x2_t poly[20]; -} data = { - /* Coefficients of polynomial P such that atan(x)~x+x*P(x^2) on - the interval [2**-1022, 1.0]. */ - .poly = { V2 (-0x1.5555555555555p-2), V2 (0x1.99999999996c1p-3), - V2 (-0x1.2492492478f88p-3), V2 (0x1.c71c71bc3951cp-4), - V2 (-0x1.745d160a7e368p-4), V2 (0x1.3b139b6a88ba1p-4), - V2 (-0x1.11100ee084227p-4), V2 (0x1.e1d0f9696f63bp-5), - V2 (-0x1.aebfe7b418581p-5), V2 (0x1.842dbe9b0d916p-5), - V2 (-0x1.5d30140ae5e99p-5), V2 (0x1.338e31eb2fbbcp-5), - V2 (-0x1.00e6eece7de8p-5), V2 (0x1.860897b29e5efp-6), - V2 (-0x1.0051381722a59p-6), V2 (0x1.14e9dc19a4a4ep-7), - V2 (-0x1.d0062b42fe3bfp-9), V2 (0x1.17739e210171ap-10), - V2 (-0x1.ab24da7be7402p-13), V2 (0x1.358851160a528p-16), }, - .pi_over_2 = V2 (0x1.921fb54442d18p+0), -}; - -#define SignMask v_u64 (0x8000000000000000) - -/* Special cases i.e. 0, infinity, NaN (fall back to scalar calls). */ -static float64x2_t VPCS_ATTR NOINLINE -special_case (float64x2_t y, float64x2_t x, float64x2_t ret, uint64x2_t cmp) -{ - return v_call2_f64 (atan2, y, x, ret, cmp); -} - -/* Returns 1 if input is the bit representation of 0, infinity or nan. */ -static inline uint64x2_t -zeroinfnan (uint64x2_t i) -{ - /* (2 * i - 1) >= (2 * asuint64 (INFINITY) - 1). */ - return vcgeq_u64 (vsubq_u64 (vaddq_u64 (i, i), v_u64 (1)), - v_u64 (2 * asuint64 (INFINITY) - 1)); -} - -/* Fast implementation of vector atan2. - Maximum observed error is 2.8 ulps: - _ZGVnN2vv_atan2 (0x1.9651a429a859ap+5, 0x1.953075f4ee26p+5) - got 0x1.92d628ab678ccp-1 - want 0x1.92d628ab678cfp-1. */ -float64x2_t VPCS_ATTR V_NAME_D2 (atan2) (float64x2_t y, float64x2_t x) -{ - const struct data *data_ptr = ptr_barrier (&data); - - uint64x2_t ix = vreinterpretq_u64_f64 (x); - uint64x2_t iy = vreinterpretq_u64_f64 (y); - - uint64x2_t special_cases = vorrq_u64 (zeroinfnan (ix), zeroinfnan (iy)); - - uint64x2_t sign_x = vandq_u64 (ix, SignMask); - uint64x2_t sign_y = vandq_u64 (iy, SignMask); - uint64x2_t sign_xy = veorq_u64 (sign_x, sign_y); - - float64x2_t ax = vabsq_f64 (x); - float64x2_t ay = vabsq_f64 (y); - - uint64x2_t pred_xlt0 = vcltzq_f64 (x); - uint64x2_t pred_aygtax = vcgtq_f64 (ay, ax); - - /* Set up z for call to atan. */ - float64x2_t n = vbslq_f64 (pred_aygtax, vnegq_f64 (ax), ay); - float64x2_t d = vbslq_f64 (pred_aygtax, ay, ax); - float64x2_t z = vdivq_f64 (n, d); - - /* Work out the correct shift. */ - float64x2_t shift = vreinterpretq_f64_u64 ( - vandq_u64 (pred_xlt0, vreinterpretq_u64_f64 (v_f64 (-2.0)))); - shift = vbslq_f64 (pred_aygtax, vaddq_f64 (shift, v_f64 (1.0)), shift); - shift = vmulq_f64 (shift, data_ptr->pi_over_2); - - /* Calculate the polynomial approximation. - Use split Estrin scheme for P(z^2) with deg(P)=19. Use split instead of - full scheme to avoid underflow in x^16. - The order 19 polynomial P approximates - (atan(sqrt(x))-sqrt(x))/x^(3/2). */ - float64x2_t z2 = vmulq_f64 (z, z); - float64x2_t x2 = vmulq_f64 (z2, z2); - float64x2_t x4 = vmulq_f64 (x2, x2); - float64x2_t x8 = vmulq_f64 (x4, x4); - float64x2_t ret - = vfmaq_f64 (v_estrin_7_f64 (z2, x2, x4, data_ptr->poly), - v_estrin_11_f64 (z2, x2, x4, x8, data_ptr->poly + 8), x8); - - /* Finalize. y = shift + z + z^3 * P(z^2). */ - ret = vfmaq_f64 (z, ret, vmulq_f64 (z2, z)); - ret = vaddq_f64 (ret, shift); - - /* Account for the sign of x and y. */ - ret = vreinterpretq_f64_u64 ( - veorq_u64 (vreinterpretq_u64_f64 (ret), sign_xy)); - - if (unlikely (v_any_u64 (special_cases))) - return special_case (y, x, ret, special_cases); - - return ret; -} - -/* Arity of 2 means no mathbench entry emitted. See test/mathbench_funcs.h. */ -PL_SIG (V, D, 2, atan2) -// TODO tighten this once __v_atan2 is fixed -PL_TEST_ULP (V_NAME_D2 (atan2), 2.9) -PL_TEST_INTERVAL (V_NAME_D2 (atan2), -10.0, 10.0, 50000) -PL_TEST_INTERVAL (V_NAME_D2 (atan2), -1.0, 1.0, 40000) -PL_TEST_INTERVAL (V_NAME_D2 (atan2), 0.0, 1.0, 40000) -PL_TEST_INTERVAL (V_NAME_D2 (atan2), 1.0, 100.0, 40000) -PL_TEST_INTERVAL (V_NAME_D2 (atan2), 1e6, 1e32, 40000) |