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-rw-r--r--pl/math/v_expm1f_inline.h63
1 files changed, 0 insertions, 63 deletions
diff --git a/pl/math/v_expm1f_inline.h b/pl/math/v_expm1f_inline.h
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--- a/pl/math/v_expm1f_inline.h
+++ /dev/null
@@ -1,63 +0,0 @@
-/*
- * Helper for single-precision routines which calculate exp(x) - 1 and do not
- * need special-case handling
- *
- * Copyright (c) 2022-2023, Arm Limited.
- * SPDX-License-Identifier: MIT OR Apache-2.0 WITH LLVM-exception
- */
-
-#ifndef PL_MATH_V_EXPM1F_INLINE_H
-#define PL_MATH_V_EXPM1F_INLINE_H
-
-#include "v_math.h"
-#include "math_config.h"
-#include "poly_advsimd_f32.h"
-
-struct v_expm1f_data
-{
- float32x4_t poly[5];
- float32x4_t invln2_and_ln2, shift;
- int32x4_t exponent_bias;
-};
-
-/* Coefficients generated using fpminimax with degree=5 in [-log(2)/2,
- log(2)/2]. Exponent bias is asuint(1.0f).
- invln2_and_ln2 Stores constants: invln2, ln2_lo, ln2_hi, 0. */
-#define V_EXPM1F_DATA \
- { \
- .poly = { V4 (0x1.fffffep-2), V4 (0x1.5554aep-3), V4 (0x1.555736p-5), \
- V4 (0x1.12287cp-7), V4 (0x1.6b55a2p-10) }, \
- .shift = V4 (0x1.8p23f), .exponent_bias = V4 (0x3f800000), \
- .invln2_and_ln2 = { 0x1.715476p+0f, 0x1.62e4p-1f, 0x1.7f7d1cp-20f, 0 }, \
- }
-
-static inline float32x4_t
-expm1f_inline (float32x4_t x, const struct v_expm1f_data *d)
-{
- /* Helper routine for calculating exp(x) - 1.
- Copied from v_expm1f_1u6.c, with all special-case handling removed - the
- calling routine should handle special values if required. */
-
- /* Reduce argument: f in [-ln2/2, ln2/2], i is exact. */
- float32x4_t j = vsubq_f32 (
- vfmaq_laneq_f32 (d->shift, x, d->invln2_and_ln2, 0), d->shift);
- int32x4_t i = vcvtq_s32_f32 (j);
- float32x4_t f = vfmsq_laneq_f32 (x, j, d->invln2_and_ln2, 1);
- f = vfmsq_laneq_f32 (f, j, d->invln2_and_ln2, 2);
-
- /* Approximate expm1(f) with polynomial P, expm1(f) ~= f + f^2 * P(f).
- Uses Estrin scheme, where the main _ZGVnN4v_expm1f routine uses
- Horner. */
- float32x4_t f2 = vmulq_f32 (f, f);
- float32x4_t f4 = vmulq_f32 (f2, f2);
- float32x4_t p = v_estrin_4_f32 (f, f2, f4, d->poly);
- p = vfmaq_f32 (f, f2, p);
-
- /* t = 2^i. */
- int32x4_t u = vaddq_s32 (vshlq_n_s32 (i, 23), d->exponent_bias);
- float32x4_t t = vreinterpretq_f32_s32 (u);
- /* expm1(x) ~= p * t + (t - 1). */
- return vfmaq_f32 (vsubq_f32 (t, v_f32 (1.0f)), p, t);
-}
-
-#endif // PL_MATH_V_EXPM1F_INLINE_H