From: nsz Date: Mon, 12 Mar 2012 21:57:10 +0000 (+0100) Subject: rename __exp to __expo2 X-Git-Url: http://nsz.repo.hu/git/?p=libm;a=commitdiff_plain;h=0376d44a890fea261506f1fc63833e7a686dca19;hp=25215b63b9aa93089a9a05d1cffc3784109228c6 rename __exp to __expo2 --- diff --git a/src/math/__exp.c b/src/math/__exp.c deleted file mode 100644 index ef14e5f..0000000 --- a/src/math/__exp.c +++ /dev/null @@ -1,51 +0,0 @@ -/* origin: FreeBSD /usr/src/lib/msun/src/k_exp.c */ -/*- - * Copyright (c) 2011 David Schultz - * All rights reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * 2. Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in the - * documentation and/or other materials provided with the distribution. - * - * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND - * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE - * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE - * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE - * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL - * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS - * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) - * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT - * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY - * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF - * SUCH DAMAGE. - */ - -#include "libm.h" - -/* - * We use exp(x) = exp(x - kln2) * 2**k, - * k is carefully chosen to minimize |exp(kln2) - 2**k| - */ -static const uint32_t k = 1799; -static const double kln2 = 1246.97177782734161156; - -/* exp(x)/2 when x is huge */ -double __expo2(double x) -{ - double scale; - int n; - - /* - * efficient scalbn(y, k-1): - * 2**(k-1) cannot be represented - * so we use that k-1 is even and scale in two steps - */ - n = (k - 1)/2; - INSERT_WORDS(scale, (0x3ff + n) << 20, 0); - return exp(x - kln2) * scale * scale; -} diff --git a/src/math/__expf.c b/src/math/__expf.c deleted file mode 100644 index 192838f..0000000 --- a/src/math/__expf.c +++ /dev/null @@ -1,51 +0,0 @@ -/* origin: FreeBSD /usr/src/lib/msun/src/k_expf.c */ -/*- - * Copyright (c) 2011 David Schultz - * All rights reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * 2. Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in the - * documentation and/or other materials provided with the distribution. - * - * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND - * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE - * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE - * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE - * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL - * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS - * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) - * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT - * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY - * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF - * SUCH DAMAGE. - */ - -#include "libm.h" - -/* - * We use exp(x) = exp(x - kln2) * 2**k, - * k is carefully chosen to minimize |exp(kln2) - 2**k| - */ -static const uint32_t k = 235; -static const float kln2 = 162.88958740f; - -/* expf(x)/2 when x is huge */ -float __expo2f(float x) -{ - float scale; - int n; - - /* - * efficient scalbnf(y, k-1): - * 2**(k-1) cannot be represented - * so we use that k-1 is even and scale in two steps - */ - n = (k - 1)/2; - SET_FLOAT_WORD(scale, (0x7f + n) << 23); - return expf(x - kln2) * scale * scale; -} diff --git a/src/math/__expo2.c b/src/math/__expo2.c new file mode 100644 index 0000000..ef14e5f --- /dev/null +++ b/src/math/__expo2.c @@ -0,0 +1,51 @@ +/* origin: FreeBSD /usr/src/lib/msun/src/k_exp.c */ +/*- + * Copyright (c) 2011 David Schultz + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include "libm.h" + +/* + * We use exp(x) = exp(x - kln2) * 2**k, + * k is carefully chosen to minimize |exp(kln2) - 2**k| + */ +static const uint32_t k = 1799; +static const double kln2 = 1246.97177782734161156; + +/* exp(x)/2 when x is huge */ +double __expo2(double x) +{ + double scale; + int n; + + /* + * efficient scalbn(y, k-1): + * 2**(k-1) cannot be represented + * so we use that k-1 is even and scale in two steps + */ + n = (k - 1)/2; + INSERT_WORDS(scale, (0x3ff + n) << 20, 0); + return exp(x - kln2) * scale * scale; +} diff --git a/src/math/__expo2f.c b/src/math/__expo2f.c new file mode 100644 index 0000000..192838f --- /dev/null +++ b/src/math/__expo2f.c @@ -0,0 +1,51 @@ +/* origin: FreeBSD /usr/src/lib/msun/src/k_expf.c */ +/*- + * Copyright (c) 2011 David Schultz + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include "libm.h" + +/* + * We use exp(x) = exp(x - kln2) * 2**k, + * k is carefully chosen to minimize |exp(kln2) - 2**k| + */ +static const uint32_t k = 235; +static const float kln2 = 162.88958740f; + +/* expf(x)/2 when x is huge */ +float __expo2f(float x) +{ + float scale; + int n; + + /* + * efficient scalbnf(y, k-1): + * 2**(k-1) cannot be represented + * so we use that k-1 is even and scale in two steps + */ + n = (k - 1)/2; + SET_FLOAT_WORD(scale, (0x7f + n) << 23); + return expf(x - kln2) * scale * scale; +}