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-rw-r--r--pl/math/log10f.c97
1 files changed, 0 insertions, 97 deletions
diff --git a/pl/math/log10f.c b/pl/math/log10f.c
deleted file mode 100644
index 5c80008e4e57..000000000000
--- a/pl/math/log10f.c
+++ /dev/null
@@ -1,97 +0,0 @@
-/*
- * Single-precision log10 function.
- *
- * Copyright (c) 2022-2023, Arm Limited.
- * SPDX-License-Identifier: MIT OR Apache-2.0 WITH LLVM-exception
- */
-
-#include <math.h>
-#include <stdint.h>
-
-#include "math_config.h"
-#include "pl_sig.h"
-#include "pl_test.h"
-
-/* Data associated to logf:
-
- LOGF_TABLE_BITS = 4
- LOGF_POLY_ORDER = 4
-
- ULP error: 0.818 (nearest rounding.)
- Relative error: 1.957 * 2^-26 (before rounding.). */
-
-#define T __logf_data.tab
-#define A __logf_data.poly
-#define Ln2 __logf_data.ln2
-#define InvLn10 __logf_data.invln10
-#define N (1 << LOGF_TABLE_BITS)
-#define OFF 0x3f330000
-
-/* This naive implementation of log10f mimics that of log
- then simply scales the result by 1/log(10) to switch from base e to
- base 10. Hence, most computations are carried out in double precision.
- Scaling before rounding to single precision is both faster and more accurate.
-
- ULP error: 0.797 ulp (nearest rounding.). */
-float
-log10f (float x)
-{
- /* double_t for better performance on targets with FLT_EVAL_METHOD==2. */
- double_t z, r, r2, y, y0, invc, logc;
- uint32_t ix, iz, tmp;
- int k, i;
-
- ix = asuint (x);
-#if WANT_ROUNDING
- /* Fix sign of zero with downward rounding when x==1. */
- if (unlikely (ix == 0x3f800000))
- return 0;
-#endif
- if (unlikely (ix - 0x00800000 >= 0x7f800000 - 0x00800000))
- {
- /* x < 0x1p-126 or inf or nan. */
- if (ix * 2 == 0)
- return __math_divzerof (1);
- if (ix == 0x7f800000) /* log(inf) == inf. */
- return x;
- if ((ix & 0x80000000) || ix * 2 >= 0xff000000)
- return __math_invalidf (x);
- /* x is subnormal, normalize it. */
- ix = asuint (x * 0x1p23f);
- ix -= 23 << 23;
- }
-
- /* 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 = ix - OFF;
- i = (tmp >> (23 - LOGF_TABLE_BITS)) % N;
- k = (int32_t) tmp >> 23; /* arithmetic shift. */
- iz = ix - (tmp & 0xff800000);
- invc = T[i].invc;
- logc = T[i].logc;
- z = (double_t) asfloat (iz);
-
- /* log(x) = log1p(z/c-1) + log(c) + k*Ln2. */
- r = z * invc - 1;
- y0 = logc + (double_t) k * Ln2;
-
- /* Pipelined polynomial evaluation to approximate log1p(r). */
- r2 = r * r;
- y = A[1] * r + A[2];
- y = A[0] * r2 + y;
- y = y * r2 + (y0 + r);
-
- /* Multiply by 1/log(10). */
- y = y * InvLn10;
-
- return eval_as_float (y);
-}
-
-PL_SIG (S, F, 1, log10, 0.01, 11.1)
-PL_TEST_ULP (log10f, 0.30)
-PL_TEST_INTERVAL (log10f, 0, 0xffff0000, 10000)
-PL_TEST_INTERVAL (log10f, 0x1p-127, 0x1p-26, 50000)
-PL_TEST_INTERVAL (log10f, 0x1p-26, 0x1p3, 50000)
-PL_TEST_INTERVAL (log10f, 0x1p-4, 0x1p4, 50000)
-PL_TEST_INTERVAL (log10f, 0, inf, 50000)