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-rw-r--r--math/v_exp2f.c117
1 files changed, 0 insertions, 117 deletions
diff --git a/math/v_exp2f.c b/math/v_exp2f.c
deleted file mode 100644
index 7f40dbaa6679..000000000000
--- a/math/v_exp2f.c
+++ /dev/null
@@ -1,117 +0,0 @@
-/*
- * Single-precision vector 2^x function.
- *
- * Copyright (c) 2019-2022, Arm Limited.
- * SPDX-License-Identifier: MIT OR Apache-2.0 WITH LLVM-exception
- */
-
-#include "mathlib.h"
-#include "v_math.h"
-#if V_SUPPORTED
-
-static const float Poly[] = {
- /* maxerr: 1.962 ulp. */
- 0x1.59977ap-10f,
- 0x1.3ce9e4p-7f,
- 0x1.c6bd32p-5f,
- 0x1.ebf9bcp-3f,
- 0x1.62e422p-1f,
-};
-#define C0 v_f32 (Poly[0])
-#define C1 v_f32 (Poly[1])
-#define C2 v_f32 (Poly[2])
-#define C3 v_f32 (Poly[3])
-#define C4 v_f32 (Poly[4])
-
-#define Shift v_f32 (0x1.8p23f)
-
-#if WANT_SIMD_EXCEPT
-
-#define TinyBound 0x20000000 /* asuint (0x1p-63). */
-#define BigBound 0x42800000 /* asuint (0x1p6). */
-
-VPCS_ATTR
-static NOINLINE v_f32_t
-specialcase (v_f32_t x, v_f32_t y, v_u32_t cmp)
-{
- /* If fenv exceptions are to be triggered correctly, fall back to the scalar
- routine to special lanes. */
- return v_call_f32 (exp2f, x, y, cmp);
-}
-
-#else
-
-VPCS_ATTR
-static v_f32_t
-specialcase (v_f32_t poly, v_f32_t n, v_u32_t e, v_f32_t absn, v_u32_t cmp1, v_f32_t scale)
-{
- /* 2^n may overflow, break it up into s1*s2. */
- v_u32_t b = v_cond_u32 (n <= v_f32 (0.0f)) & v_u32 (0x82000000);
- v_f32_t s1 = v_as_f32_u32 (v_u32 (0x7f000000) + b);
- v_f32_t s2 = v_as_f32_u32 (e - b);
- v_u32_t cmp2 = v_cond_u32 (absn > v_f32 (192.0f));
- v_u32_t r2 = v_as_u32_f32 (s1 * s1);
- v_u32_t r1 = v_as_u32_f32 (v_fma_f32 (poly, s2, s2) * s1);
- /* Similar to r1 but avoids double rounding in the subnormal range. */
- v_u32_t r0 = v_as_u32_f32 (v_fma_f32 (poly, scale, scale));
- return v_as_f32_u32 ((cmp2 & r2) | (~cmp2 & cmp1 & r1) | (~cmp1 & r0));
-}
-
-#endif
-
-VPCS_ATTR
-v_f32_t
-V_NAME(exp2f) (v_f32_t x)
-{
- v_f32_t n, r, r2, scale, p, q, poly;
- v_u32_t cmp, e;
-
-#if WANT_SIMD_EXCEPT
- cmp = v_cond_u32 ((v_as_u32_f32 (x) & 0x7fffffff) - TinyBound
- >= BigBound - TinyBound);
- v_f32_t xm = x;
- /* If any lanes are special, mask them with 1 and retain a copy of x to allow
- specialcase to fix special lanes later. This is only necessary if fenv
- exceptions are to be triggered correctly. */
- if (unlikely (v_any_u32 (cmp)))
- x = v_sel_f32 (cmp, v_f32 (1), x);
-#endif
-
- /* exp2(x) = 2^n (1 + poly(r)), with 1 + poly(r) in [1/sqrt(2),sqrt(2)]
- x = n + r, with r in [-1/2, 1/2]. */
-#if 0
- v_f32_t z;
- z = x + Shift;
- n = z - Shift;
- r = x - n;
- e = v_as_u32_f32 (z) << 23;
-#else
- n = v_round_f32 (x);
- r = x - n;
- e = v_as_u32_s32 (v_round_s32 (x)) << 23;
-#endif
- scale = v_as_f32_u32 (e + v_u32 (0x3f800000));
-
-#if !WANT_SIMD_EXCEPT
- v_f32_t absn = v_abs_f32 (n);
- cmp = v_cond_u32 (absn > v_f32 (126.0f));
-#endif
-
- r2 = r * r;
- p = v_fma_f32 (C0, r, C1);
- q = v_fma_f32 (C2, r, C3);
- q = v_fma_f32 (p, r2, q);
- p = C4 * r;
- poly = v_fma_f32 (q, r2, p);
-
- if (unlikely (v_any_u32 (cmp)))
-#if WANT_SIMD_EXCEPT
- return specialcase (xm, v_fma_f32 (poly, scale, scale), cmp);
-#else
- return specialcase (poly, n, e, absn, cmp, scale);
-#endif
-
- return v_fma_f32 (poly, scale, scale);
-}
-VPCS_ALIAS
-#endif