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-rw-r--r--pl/math/acosh_3u.c66
1 files changed, 0 insertions, 66 deletions
diff --git a/pl/math/acosh_3u.c b/pl/math/acosh_3u.c
deleted file mode 100644
index 4e2cb6737ba8..000000000000
--- a/pl/math/acosh_3u.c
+++ /dev/null
@@ -1,66 +0,0 @@
-/*
- * Double-precision acosh(x) function.
- *
- * Copyright (c) 2022-2023, Arm Limited.
- * SPDX-License-Identifier: MIT OR Apache-2.0 WITH LLVM-exception
- */
-
-#include "math_config.h"
-#include "pl_sig.h"
-#include "pl_test.h"
-
-#define Ln2 (0x1.62e42fefa39efp-1)
-#define MinusZero (0x8000000000000000)
-#define SquareLim (0x5fe0000000000000) /* asuint64(0x1.0p511). */
-#define Two (0x4000000000000000) /* asuint64(2.0). */
-
-double
-optr_aor_log_f64 (double);
-
-double
-log1p (double);
-
-/* acosh approximation using a variety of approaches on different intervals:
-
- acosh(x) = ln(x + sqrt(x * x - 1)).
-
- x >= 2^511: We cannot square x without overflow. For huge x, sqrt(x*x - 1) is
- close enough to x that we can calculate the result by ln(2x) == ln(x) +
- ln(2). The greatest observed error in this region is 0.98 ULP:
- acosh(0x1.1b9bf42923d1dp+853) got 0x1.28066a11a7c7fp+9
- want 0x1.28066a11a7c8p+9.
-
- x > 2: Calculate the result directly using definition of acosh(x). Greatest
- observed error in this region is 1.33 ULP:
- acosh(0x1.1e45d14bfcfa2p+1) got 0x1.71a06f50c34b5p+0
- want 0x1.71a06f50c34b6p+0.
-
- 0 <= x <= 2: Calculate the result using log1p. For x < 1, acosh(x) is
- undefined. For 1 <= x <= 2, the largest observed error is 2.69 ULP:
- acosh(0x1.073528248093p+0) got 0x1.e4d9bd20684f3p-3
- want 0x1.e4d9bd20684f6p-3. */
-double
-acosh (double x)
-{
- uint64_t ix = asuint64 (x);
-
- if (unlikely (ix >= MinusZero))
- return __math_invalid (x);
-
- if (unlikely (ix >= SquareLim))
- return optr_aor_log_f64 (x) + Ln2;
-
- if (ix >= Two)
- return optr_aor_log_f64 (x + sqrt (x * x - 1));
-
- double xm1 = x - 1;
- return log1p (xm1 + sqrt (2 * xm1 + xm1 * xm1));
-}
-
-PL_SIG (S, D, 1, acosh, 1.0, 10.0)
-PL_TEST_ULP (acosh, 2.19)
-PL_TEST_INTERVAL (acosh, 0, 1, 10000)
-PL_TEST_INTERVAL (acosh, 1, 2, 100000)
-PL_TEST_INTERVAL (acosh, 2, 0x1p511, 100000)
-PL_TEST_INTERVAL (acosh, 0x1p511, inf, 100000)
-PL_TEST_INTERVAL (acosh, -0, -inf, 10000)