i386/string/bcopy_scalar.s

   1 /*
   2  * Copyright (c) 2003-2006 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28
  29 /*-
  30  * Copyright (c) 1990 The Regents of the University of California.
  31  * All rights reserved.
  32  *
  33  * This code is derived from locore.s.
  34  *
  35  * Redistribution and use in source and binary forms, with or without
  36  * modification, are permitted provided that the following conditions
  37  * are met:
  38  * 1. Redistributions of source code must retain the above copyright
  39  *    notice, this list of conditions and the following disclaimer.
  40  * 2. Redistributions in binary form must reproduce the above copyright
  41  *    notice, this list of conditions and the following disclaimer in the
  42  *    documentation and/or other materials provided with the distribution.
  43  * 3. All advertising materials mentioning features or use of this software
  44  *    must display the following acknowledgement:
  45  *      This product includes software developed by the University of
  46  *      California, Berkeley and its contributors.
  47  * 4. Neither the name of the University nor the names of its contributors
  48  *    may be used to endorse or promote products derived from this software
  49  *    without specific prior written permission.
  50  *
  51  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  52  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  53  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  54  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  55  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  56  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  57  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  58  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  59  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  60  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  61  * SUCH DAMAGE.
  62  */
  63
  64 #include <sys/appleapiopts.h>
  65 #include <machine/cpu_capabilities.h>
  66 #include <platfunc.h>
  67 #include <machine/asm.h>
  68
  69         /*
  70          * (ov)bcopy (src,dst,cnt)
  71          *  ws@tools.de     (Wolfgang Solfrank, TooLs GmbH) +49-228-985800
  72          */
  73
  74 PLATFUNC_FUNCTION_START_GENERIC(bcopy, scalar, 32, 5)
  75         pushl   %ebp        /* set up a frame for backtraces */
  76         movl    %esp,%ebp
  77         pushl   %esi
  78         pushl   %edi
  79         movl    8(%ebp),%esi
  80         movl    12(%ebp),%edi
  81         jmp 1f
  82
  83 PLATFUNC_FUNCTION_START_GENERIC(memcpy, scalar, 32, 0)
  84 PLATFUNC_FUNCTION_START_GENERIC(memmove, scalar, 32, 0)
  85         pushl   %ebp            /* set up a frame for backtraces */
  86         movl    %esp,%ebp
  87         pushl   %esi
  88         pushl   %edi
  89         movl    8(%ebp),%edi
  90         movl    12(%ebp),%esi
  91         movl    %edi,%eax
  92 1:
  93         movl    16(%ebp),%ecx
  94         movl    %edi,%edx
  95         subl    %esi,%edx
  96         cmpl    %ecx,%edx       /* overlapping? */
  97         jb      2f
  98         cld                     /* nope, copy forwards. */
  99         movl    %ecx,%edx
 100         shrl    $2,%ecx         /* copy by words */
 101         rep
 102         movsl
 103         movl    %edx,%ecx
 104         andl    $3,%ecx         /* any bytes left? */
 105         rep
 106         movsb
 107         popl    %edi
 108         popl    %esi
 109         popl    %ebp
 110         ret
 111 2:
 112         addl    %ecx,%edi       /* copy backwards. */
 113         addl    %ecx,%esi
 114         std
 115         movl    %ecx,%edx
 116         andl    $3,%ecx         /* any fractional bytes? */
 117         decl    %edi
 118         decl    %esi
 119         rep
 120         movsb
 121         movl    %edx,%ecx       /* copy remainder by words */
 122         shrl    $2,%ecx
 123         subl    $3,%esi
 124         subl    $3,%edi
 125         rep
 126         movsl
 127         popl    %edi
 128         popl    %esi
 129         popl    %ebp
 130         cld
 131         ret
 132
 133 PLATFUNC_DESCRIPTOR(bcopy,scalar,0,0)
 134 PLATFUNC_DESCRIPTOR(memcpy,scalar,0,0)
 135 PLATFUNC_DESCRIPTOR(memmove,scalar,0,0)