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Diffstat (limited to 'pl/math/v_log2f_2u5.c')
-rw-r--r--pl/math/v_log2f_2u5.c77
1 files changed, 0 insertions, 77 deletions
diff --git a/pl/math/v_log2f_2u5.c b/pl/math/v_log2f_2u5.c
deleted file mode 100644
index c64d88742136..000000000000
--- a/pl/math/v_log2f_2u5.c
+++ /dev/null
@@ -1,77 +0,0 @@
-/*
- * Single-precision vector log2 function.
- *
- * Copyright (c) 2022-2023, Arm Limited.
- * SPDX-License-Identifier: MIT OR Apache-2.0 WITH LLVM-exception
- */
-
-#include "v_math.h"
-#include "poly_advsimd_f32.h"
-#include "pl_sig.h"
-#include "pl_test.h"
-
-static const struct data
-{
- uint32x4_t min_norm;
- uint16x8_t special_bound;
- uint32x4_t off, mantissa_mask;
- float32x4_t poly[9];
-} data = {
- /* Coefficients generated using Remez algorithm approximate
- log2(1+r)/r for r in [ -1/3, 1/3 ].
- rel error: 0x1.c4c4b0cp-26. */
- .poly = { V4 (0x1.715476p0f), /* (float)(1 / ln(2)). */
- V4 (-0x1.715458p-1f), V4 (0x1.ec701cp-2f), V4 (-0x1.7171a4p-2f),
- V4 (0x1.27a0b8p-2f), V4 (-0x1.e5143ep-3f), V4 (0x1.9d8ecap-3f),
- V4 (-0x1.c675bp-3f), V4 (0x1.9e495p-3f) },
- .min_norm = V4 (0x00800000),
- .special_bound = V8 (0x7f00), /* asuint32(inf) - min_norm. */
- .off = V4 (0x3f2aaaab), /* 0.666667. */
- .mantissa_mask = V4 (0x007fffff),
-};
-
-static float32x4_t VPCS_ATTR NOINLINE
-special_case (float32x4_t x, float32x4_t n, float32x4_t p, float32x4_t r,
- uint16x4_t cmp)
-{
- /* Fall back to scalar code. */
- return v_call_f32 (log2f, x, vfmaq_f32 (n, p, r), vmovl_u16 (cmp));
-}
-
-/* Fast implementation for single precision AdvSIMD log2,
- relies on same argument reduction as AdvSIMD logf.
- Maximum error: 2.48 ULPs
- _ZGVnN4v_log2f(0x1.558174p+0) got 0x1.a9be84p-2
- want 0x1.a9be8p-2. */
-float32x4_t VPCS_ATTR V_NAME_F1 (log2) (float32x4_t x)
-{
- const struct data *d = ptr_barrier (&data);
- uint32x4_t u = vreinterpretq_u32_f32 (x);
- uint16x4_t special = vcge_u16 (vsubhn_u32 (u, d->min_norm),
- vget_low_u16 (d->special_bound));
-
- /* x = 2^n * (1+r), where 2/3 < 1+r < 4/3. */
- u = vsubq_u32 (u, d->off);
- float32x4_t n = vcvtq_f32_s32 (
- vshrq_n_s32 (vreinterpretq_s32_u32 (u), 23)); /* signextend. */
- u = vaddq_u32 (vandq_u32 (u, d->mantissa_mask), d->off);
- float32x4_t r = vsubq_f32 (vreinterpretq_f32_u32 (u), v_f32 (1.0f));
-
- /* y = log2(1+r) + n. */
- float32x4_t r2 = vmulq_f32 (r, r);
- float32x4_t p = v_pw_horner_8_f32 (r, r2, d->poly);
-
- if (unlikely (v_any_u16h (special)))
- return special_case (x, n, p, r, special);
- return vfmaq_f32 (n, p, r);
-}
-
-PL_SIG (V, F, 1, log2, 0.01, 11.1)
-PL_TEST_ULP (V_NAME_F1 (log2), 1.99)
-PL_TEST_EXPECT_FENV_ALWAYS (V_NAME_F1 (log2))
-PL_TEST_INTERVAL (V_NAME_F1 (log2), -0.0, -0x1p126, 100)
-PL_TEST_INTERVAL (V_NAME_F1 (log2), 0x1p-149, 0x1p-126, 4000)
-PL_TEST_INTERVAL (V_NAME_F1 (log2), 0x1p-126, 0x1p-23, 50000)
-PL_TEST_INTERVAL (V_NAME_F1 (log2), 0x1p-23, 1.0, 50000)
-PL_TEST_INTERVAL (V_NAME_F1 (log2), 1.0, 100, 50000)
-PL_TEST_INTERVAL (V_NAME_F1 (log2), 100, inf, 50000)