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Diffstat (limited to 'math/aarch64/v_log.c')
-rw-r--r--math/aarch64/v_log.c100
1 files changed, 0 insertions, 100 deletions
diff --git a/math/aarch64/v_log.c b/math/aarch64/v_log.c
deleted file mode 100644
index 1d1c1fa62c04..000000000000
--- a/math/aarch64/v_log.c
+++ /dev/null
@@ -1,100 +0,0 @@
-/*
- * Double-precision vector log(x) function.
- *
- * Copyright (c) 2019-2023, Arm Limited.
- * SPDX-License-Identifier: MIT OR Apache-2.0 WITH LLVM-exception
- */
-
-#include "mathlib.h"
-#include "v_math.h"
-
-static const struct data
-{
- uint64x2_t min_norm;
- uint32x4_t special_bound;
- float64x2_t poly[5];
- float64x2_t ln2;
- uint64x2_t sign_exp_mask;
-} data = {
- /* Worst-case error: 1.17 + 0.5 ulp.
- Rel error: 0x1.6272e588p-56 in [ -0x1.fc1p-9 0x1.009p-8 ]. */
- .poly = { V2 (-0x1.ffffffffffff7p-2), V2 (0x1.55555555170d4p-2),
- V2 (-0x1.0000000399c27p-2), V2 (0x1.999b2e90e94cap-3),
- V2 (-0x1.554e550bd501ep-3) },
- .ln2 = V2 (0x1.62e42fefa39efp-1),
- .min_norm = V2 (0x0010000000000000),
- .special_bound = V4 (0x7fe00000), /* asuint64(inf) - min_norm. */
- .sign_exp_mask = V2 (0xfff0000000000000)
-};
-
-#define A(i) d->poly[i]
-#define N (1 << V_LOG_TABLE_BITS)
-#define IndexMask (N - 1)
-#define Off v_u64 (0x3fe6900900000000)
-
-struct entry
-{
- float64x2_t invc;
- float64x2_t logc;
-};
-
-static inline struct entry
-lookup (uint64x2_t i)
-{
- /* Since N is a power of 2, n % N = n & (N - 1). */
- struct entry e;
- uint64_t i0 = (i[0] >> (52 - V_LOG_TABLE_BITS)) & IndexMask;
- uint64_t i1 = (i[1] >> (52 - V_LOG_TABLE_BITS)) & IndexMask;
- float64x2_t e0 = vld1q_f64 (&__v_log_data.table[i0].invc);
- float64x2_t e1 = vld1q_f64 (&__v_log_data.table[i1].invc);
- e.invc = vuzp1q_f64 (e0, e1);
- e.logc = vuzp2q_f64 (e0, e1);
- return e;
-}
-
-static float64x2_t VPCS_ATTR NOINLINE
-special_case (float64x2_t x, float64x2_t y, float64x2_t hi, float64x2_t r2,
- uint32x2_t cmp)
-{
- return v_call_f64 (log, x, vfmaq_f64 (hi, y, r2), vmovl_u32 (cmp));
-}
-
-float64x2_t VPCS_ATTR V_NAME_D1 (log) (float64x2_t x)
-{
- const struct data *d = ptr_barrier (&data);
- float64x2_t z, r, r2, p, y, kd, hi;
- uint64x2_t ix, iz, tmp;
- uint32x2_t cmp;
- int64x2_t k;
- struct entry e;
-
- ix = vreinterpretq_u64_f64 (x);
- cmp = vcge_u32 (vsubhn_u64 (ix, d->min_norm),
- vget_low_u32 (d->special_bound));
-
- /* x = 2^k z; where z is in range [Off,2*Off) and exact.
- The range is split into N subintervals.
- The ith subinterval contains z and c is near its center. */
- tmp = vsubq_u64 (ix, Off);
- k = vshrq_n_s64 (vreinterpretq_s64_u64 (tmp), 52); /* arithmetic shift. */
- iz = vsubq_u64 (ix, vandq_u64 (tmp, d->sign_exp_mask));
- z = vreinterpretq_f64_u64 (iz);
- e = lookup (tmp);
-
- /* log(x) = log1p(z/c-1) + log(c) + k*Ln2. */
- r = vfmaq_f64 (v_f64 (-1.0), z, e.invc);
- kd = vcvtq_f64_s64 (k);
-
- /* hi = r + log(c) + k*Ln2. */
- hi = vfmaq_f64 (vaddq_f64 (e.logc, r), kd, d->ln2);
- /* y = r2*(A0 + r*A1 + r2*(A2 + r*A3 + r2*A4)) + hi. */
- r2 = vmulq_f64 (r, r);
- y = vfmaq_f64 (A (2), A (3), r);
- p = vfmaq_f64 (A (0), A (1), r);
- y = vfmaq_f64 (y, A (4), r2);
- y = vfmaq_f64 (p, y, r2);
-
- if (unlikely (v_any_u32h (cmp)))
- return special_case (x, y, hi, r2, cmp);
- return vfmaq_f64 (hi, y, r2);
-}