1 //===-- Common constants for math functions ---------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #ifndef LLVM_LIBC_SRC_MATH_GENERIC_COMMON_CONSTANTS_H
10 #define LLVM_LIBC_SRC_MATH_GENERIC_COMMON_CONSTANTS_H
11 
12 namespace __llvm_libc {
13 
14 // Lookup table for (1/f) where f = 1 + n*2^(-7), n = 0..127.
15 extern const double ONE_OVER_F[128];
16 
17 // Lookup table for log(f) = log(1 + n*2^(-7)) where n = 0..127.
18 extern const double LOG_F[128];
19 
20 // Lookup table for exp(m) with m = -104, ..., 89.
21 //   -104 = floor(log(single precision's min denormal))
22 //     89 = ceil(log(single precision's max normal))
23 // Table is generated with Sollya as follow:
24 // > display = hexadecimal;
25 // > for i from -104 to 89 do { D(exp(i)); };
26 extern const double EXP_M1[195];
27 
28 // Lookup table for exp(m * 2^(-7)) with m = 0, ..., 127.
29 // Table is generated with Sollya as follow:
30 // > display = hexadecimal;
31 // > for i from 0 to 127 do { D(exp(i / 128)); };
32 extern const double EXP_M2[128];
33 
34 } // namespace __llvm_libc
35 
36 #endif // LLVM_LIBC_SRC_MATH_GENERIC_COMMON_CONSTANTS_H
37