diff options
Diffstat (limited to 'sysdeps/i386/memcopy.h')
| -rw-r--r-- | sysdeps/i386/memcopy.h | 86 |
1 files changed, 86 insertions, 0 deletions
diff --git a/sysdeps/i386/memcopy.h b/sysdeps/i386/memcopy.h new file mode 100644 index 0000000000..506d3ea54d --- /dev/null +++ b/sysdeps/i386/memcopy.h @@ -0,0 +1,86 @@ +/* memcopy.h -- definitions for memory copy functions. i386 version. + Copyright (C) 1991 Free Software Foundation, Inc. + Contributed by Torbjorn Granlund (tege@sics.se). + +The GNU C Library is free software; you can redistribute it and/or +modify it under the terms of the GNU Library General Public License as +published by the Free Software Foundation; either version 2 of the +License, or (at your option) any later version. + +The GNU C Library 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 +Library General Public License for more details. + +You should have received a copy of the GNU Library General Public +License along with the GNU C Library; see the file COPYING.LIB. If +not, write to the Free Software Foundation, Inc., 675 Mass Ave, +Cambridge, MA 02139, USA. */ + +#include <sysdeps/generic/memcopy.h> + +#undef OP_T_THRES +#define OP_T_THRES 8 + +#undef BYTE_COPY_FWD +#define BYTE_COPY_FWD(dst_bp, src_bp, nbytes) \ + asm volatile(/* Clear the direction flag, so copying goes forward. */ \ + "cld\n" \ + /* Copy bytes. */ \ + "rep\n" \ + "movsb" : \ + "=D" (dst_bp), "=S" (src_bp) : \ + "0" (dst_bp), "1" (src_bp), "c" (nbytes) : \ + "cx") + +#undef BYTE_COPY_BWD +#define BYTE_COPY_BWD(dst_ep, src_ep, nbytes) \ + do \ + { \ + asm volatile(/* Set the direction flag, so copying goes backwards. */ \ + "std\n" \ + /* Copy bytes. */ \ + "rep\n" \ + "movsb\n" \ + /* Clear the dir flag. Convention says it should be 0. */ \ + "cld" : \ + "=D" (dst_ep), "=S" (src_ep) : \ + "0" (dst_ep - 1), "1" (src_ep - 1), "c" (nbytes) : \ + "cx"); \ + dst_ep += 1; \ + src_ep += 1; \ + } while (0) + +#undef WORD_COPY_FWD +#define WORD_COPY_FWD(dst_bp, src_bp, nbytes_left, nbytes) \ + do \ + { \ + asm volatile(/* Clear the direction flag, so copying goes forward. */ \ + "cld\n" \ + /* Copy longwords. */ \ + "rep\n" \ + "movsl" : \ + "=D" (dst_bp), "=S" (src_bp) : \ + "0" (dst_bp), "1" (src_bp), "c" ((nbytes) / 4) : \ + "cx"); \ + (nbytes_left) = (nbytes) % 4; \ + } while (0) + +#undef WORD_COPY_BWD +#define WORD_COPY_BWD(dst_ep, src_ep, nbytes_left, nbytes) \ + do \ + { \ + asm volatile(/* Set the direction flag, so copying goes backwards. */ \ + "std\n" \ + /* Copy longwords. */ \ + "rep\n" \ + "movsl\n" \ + /* Clear the dir flag. Convention says it should be 0. */ \ + "cld" : \ + "=D" (dst_ep), "=S" (src_ep) : \ + "0" (dst_ep - 4), "1" (src_ep - 4), "c" ((nbytes) / 4) : \ + "cx"); \ + dst_ep += 4; \ + src_ep += 4; \ + (nbytes_left) = (nbytes) % 4; \ + } while (0) |