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author | Ben Cheng <bccheng@google.com> | 2014-03-25 22:37:19 -0700 |
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committer | Ben Cheng <bccheng@google.com> | 2014-03-25 22:37:19 -0700 |
commit | 1bc5aee63eb72b341f506ad058502cd0361f0d10 (patch) | |
tree | c607e8252f3405424ff15bc2d00aa38dadbb2518 /gcc-4.9/libgfortran/generated/pow_i16_i8.c | |
parent | 283a0bf58fcf333c58a2a92c3ebbc41fb9eb1fdb (diff) | |
download | toolchain_gcc-1bc5aee63eb72b341f506ad058502cd0361f0d10.tar.gz toolchain_gcc-1bc5aee63eb72b341f506ad058502cd0361f0d10.tar.bz2 toolchain_gcc-1bc5aee63eb72b341f506ad058502cd0361f0d10.zip |
Initial checkin of GCC 4.9.0 from trunk (r208799).
Change-Id: I48a3c08bb98542aa215912a75f03c0890e497dba
Diffstat (limited to 'gcc-4.9/libgfortran/generated/pow_i16_i8.c')
-rw-r--r-- | gcc-4.9/libgfortran/generated/pow_i16_i8.c | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/gcc-4.9/libgfortran/generated/pow_i16_i8.c b/gcc-4.9/libgfortran/generated/pow_i16_i8.c new file mode 100644 index 000000000..d5e8fda8f --- /dev/null +++ b/gcc-4.9/libgfortran/generated/pow_i16_i8.c @@ -0,0 +1,77 @@ +/* Support routines for the intrinsic power (**) operator. + Copyright (C) 2004-2014 Free Software Foundation, Inc. + Contributed by Paul Brook + +This file is part of the GNU Fortran 95 runtime library (libgfortran). + +Libgfortran is free software; you can redistribute it and/or +modify it under the terms of the GNU General Public +License as published by the Free Software Foundation; either +version 3 of the License, or (at your option) any later version. + +Libgfortran is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details. + +Under Section 7 of GPL version 3, you are granted additional +permissions described in the GCC Runtime Library Exception, version +3.1, as published by the Free Software Foundation. + +You should have received a copy of the GNU General Public License and +a copy of the GCC Runtime Library Exception along with this program; +see the files COPYING3 and COPYING.RUNTIME respectively. If not, see +<http://www.gnu.org/licenses/>. */ + +#include "libgfortran.h" + + +/* Use Binary Method to calculate the powi. This is not an optimal but + a simple and reasonable arithmetic. See section 4.6.3, "Evaluation of + Powers" of Donald E. Knuth, "Seminumerical Algorithms", Vol. 2, "The Art + of Computer Programming", 3rd Edition, 1998. */ + +#if defined (HAVE_GFC_INTEGER_16) && defined (HAVE_GFC_INTEGER_8) + +GFC_INTEGER_16 pow_i16_i8 (GFC_INTEGER_16 a, GFC_INTEGER_8 b); +export_proto(pow_i16_i8); + +GFC_INTEGER_16 +pow_i16_i8 (GFC_INTEGER_16 a, GFC_INTEGER_8 b) +{ + GFC_INTEGER_16 pow, x; + GFC_INTEGER_8 n; + GFC_UINTEGER_8 u; + + n = b; + x = a; + pow = 1; + if (n != 0) + { + if (n < 0) + { + if (x == 1) + return 1; + if (x == -1) + return (n & 1) ? -1 : 1; + return (x == 0) ? 1 / x : 0; + } + else + { + u = n; + } + for (;;) + { + if (u & 1) + pow *= x; + u >>= 1; + if (u) + x *= x; + else + break; + } + } + return pow; +} + +#endif |