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- /* $Id: ctrl87.c,v 1.1.1.2 1998/04/15 19:22:16 lhecking Exp $ */
-
-
- /* GNUPLOT - ctrl87.c */
-
- /*[
- * Copyright 1986 - 1993, 1998 Thomas Williams, Colin Kelley
- *
- * Permission to use, copy, and distribute this software and its
- * documentation for any purpose with or without fee is hereby granted,
- * provided that the above copyright notice appear in all copies and
- * that both that copyright notice and this permission notice appear
- * in supporting documentation.
- *
- * Permission to modify the software is granted, but not the right to
- * distribute the complete modified source code. Modifications are to
- * be distributed as patches to the released version. Permission to
- * distribute binaries produced by compiling modified sources is granted,
- * provided you
- * 1. distribute the corresponding source modifications from the
- * released version in the form of a patch file along with the binaries,
- * 2. add special version identification to distinguish your version
- * in addition to the base release version number,
- * 3. provide your name and address as the primary contact for the
- * support of your modified version, and
- * 4. retain our contact information in regard to use of the base
- * software.
- * Permission to distribute the released version of the source code along
- * with corresponding source modifications in the form of a patch file is
- * granted with same provisions 2 through 4 for binary distributions.
- *
- * This software is provided "as is" without express or implied warranty
- * to the extent permitted by applicable law.
- ]*/
-
-
- #define __CONTROL87_C__
-
-
- #include "ctrl87.h"
-
-
- /***** _control87 *****/
- unsigned short _control87(unsigned short newcw, unsigned short mask)
- {
- unsigned short cw;
-
- asm volatile(" \n\
- wait \n\
- fstcw %0 "
- : /* outputs */ "=g" (cw)
- : /* inputs */
- );
-
- if(mask) { /* mask is not 0 */
- asm volatile(" \n\
- mov %2, %%ax \n\
- mov %3, %%bx \n\
- and %%bx, %%ax \n\
- not %%bx \n\
- nop \n\
- wait \n\
- mov %1, %%dx \n\
- and %%bx, %%dx \n\
- or %%ax, %%dx \n\
- mov %%dx, %0 \n\
- wait \n\
- fldcw %1 "
- : /* outputs */ "=g" (cw)
- : /* inputs */ "g" (cw), "g" (newcw), "g" (mask)
- : /* registers */ "ax", "bx", "dx"
- );
- }
-
- return cw;
- } /* _control87 */
-