7d7b8bfe55
* acinclude.m4 (LIBGFOR_CHECK_ATTRIBUTE_VISIBILITY): New. (LIBGFOR_CHECK_ATTRIBUTE_DLLEXPORT): New. (LIBGFOR_CHECK_ATTRIBUTE_ALIAS): New. * configure.ac: Use them. * configure, config.h.in, aclocal.m4: Rebuild. * libgfortran.h (prefix): Remove. (PREFIX, IPREFIX): New. (sym_rename, sym_rename1, sym_rename2): New. (internal_proto, export_proto, export_proto_np): New. (iexport_proto, iexport): New. (iexport_data_proto, iexport_data): New. * intrinsics/abort.c, intrinsics/args.c, intrinsics/associated.c, intrinsics/cpu_time.c, intrinsics/cshift0.c, intrinsics/date_and_time.c, intrinsics/env.c, intrinsics/eoshift0.c, intrinsics/eoshift2.c, intrinsics/etime.c, intrinsics/exit.c, intrinsics/flush.c, intrinsics/fnum.c, intrinsics/getXid.c, intrinsics/getcwd.c, intrinsics/ishftc.c, intrinsics/mvbits.c, intrinsics/pack_generic.c, intrinsics/rand.c, intrinsics/random.c, intrinsics/reshape_generic.c, intrinsics/size.c, intrinsics/spread_generic.c, intrinsics/stat.c, intrinsics/string_intrinsics.c, intrinsics/system.c, intrinsics/system_clock.c, intrinsics/transpose_generic.c, intrinsics/umask.c, intrinsics/unlink.c, intrinsics/unpack_generic.c, io/backspace.c, io/close.c, io/endfile.c, io/inquire.c, io/io.h, io/open.c, io/rewind.c, io/transfer.c, libgfortran.h, m4/cshift1.m4, m4/dotprod.m4, m4/dotprodc.m4, m4/dotprodl.m4, m4/eoshift1.m4, m4/eoshift3.m4, m4/exponent.m4, m4/fraction.m4, m4/iforeach.m4, m4/ifunction.m4, m4/matmul.m4, m4/matmull.m4, m4/nearest.m4, m4/pow.m4, m4/reshape.m4, m4/set_exponent.m4, m4/shape.m4, m4/transpose.m4, runtime/environ.c, runtime/error.c, runtime/in_pack_generic.c, runtime/in_unpack_generic.c, runtime/main.c, runtime/memory.c, runtime/pause.c, runtime/select.c, runtime/stop.c: Use them to mark symbols internal or external. * generated/*: Rebuild. From-SVN: r92045
64 lines
1.6 KiB
C
64 lines
1.6 KiB
C
/* Support routines for the intrinsic power (**) operator.
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Copyright 2004 Free Software Foundation, Inc.
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Contributed by Paul Brook
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This file is part of the GNU Fortran 95 runtime library (libgfor).
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Libgfor is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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Ligbfor is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with libgfor; see the file COPYING.LIB. If not,
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write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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Boston, MA 02111-1307, USA. */
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#include "config.h"
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#include "libgfortran.h"
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/* Use Binary Method to calculate the powi. This is not an optimal but
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a simple and reasonable arithmetic. See section 4.6.3, "Evaluation of
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Powers" of Donald E. Knuth, "Seminumerical Algorithms", Vol. 2, "The Art
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of Computer Programming", 3rd Edition, 1998. */
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GFC_REAL_4 pow_r4_i4 (GFC_REAL_4 a, GFC_INTEGER_4 b);
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export_proto(pow_r4_i4);
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GFC_REAL_4
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pow_r4_i4 (GFC_REAL_4 a, GFC_INTEGER_4 b)
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{
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GFC_REAL_4 pow, x;
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GFC_INTEGER_4 n, u;
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n = b;
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x = a;
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pow = 1;
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if (n != 0)
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{
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if (n < 0)
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{
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n = -n;
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x = pow / x;
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}
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u = n;
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for (;;)
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{
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if (u & 1)
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pow *= x;
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u >>= 1;
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if (u)
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x *= x;
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else
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break;
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}
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}
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return pow;
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}
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