osfmk/i386/commpage/bcopy_scalar.s

   1 /*
   2  * Copyright (c) 2003 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_OSREFERENCE_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
  10  * License may not be used to create, or enable the creation or
  11  * redistribution of, unlawful or unlicensed copies of an Apple operating
  12  * system, or to circumvent, violate, or enable the circumvention or
  13  * violation of, any terms of an Apple operating system software license
  14  * agreement.
  15  *
  16  * Please obtain a copy of the License at
  17  * http://www.opensource.apple.com/apsl/ and read it before using this
  18  * file.
  19  *
  20  * The Original Code and all software distributed under the License are
  21  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  22  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  23  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  24  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  25  * Please see the License for the specific language governing rights and
  26  * limitations under the License.
  27  *
  28  * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
  29  */
  30
  31 /*-
  32  * Copyright (c) 1990 The Regents of the University of California.
  33  * All rights reserved.
  34  *
  35  * This code is derived from locore.s.
  36  *
  37  * Redistribution and use in source and binary forms, with or without
  38  * modification, are permitted provided that the following conditions
  39  * are met:
  40  * 1. Redistributions of source code must retain the above copyright
  41  *    notice, this list of conditions and the following disclaimer.
  42  * 2. Redistributions in binary form must reproduce the above copyright
  43  *    notice, this list of conditions and the following disclaimer in the
  44  *    documentation and/or other materials provided with the distribution.
  45  * 3. All advertising materials mentioning features or use of this software
  46  *    must display the following acknowledgement:
  47  *      This product includes software developed by the University of
  48  *      California, Berkeley and its contributors.
  49  * 4. Neither the name of the University nor the names of its contributors
  50  *    may be used to endorse or promote products derived from this software
  51  *    without specific prior written permission.
  52  *
  53  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  54  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  55  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  56  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  57  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  58  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  59  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  60  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  61  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  62  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  63  * SUCH DAMAGE.
  64  */
  65
  66 #include <sys/appleapiopts.h>
  67 #include <machine/cpu_capabilities.h>
  68 #include <machine/commpage.h>
  69 #include <machine/asm.h>
  70
  71         /*
  72          * (ov)bcopy (src,dst,cnt)
  73          *  ws@tools.de     (Wolfgang Solfrank, TooLs GmbH) +49-228-985800
  74          */
  75
  76 .text
  77 .align 5, 0x90
  78 Lbcopy_scalar:
  79         pushl   %esi
  80         pushl   %edi
  81         movl    12(%esp),%esi
  82         movl    16(%esp),%edi
  83         jmp     1f
  84 /*
  85 ** These need to be 32 bytes from Lbcopy_scalar
  86 */
  87 .align 5, 0x90
  88 Lmemcpy_scalar:
  89 Lmemmove_scalar:
  90         pushl   %esi
  91         pushl   %edi
  92         movl    12(%esp),%edi
  93         movl    16(%esp),%esi
  94         movl    %edi,%eax
  95 1:
  96         movl    20(%esp),%ecx
  97         movl    %edi,%edx
  98         subl    %esi,%edx
  99         cmpl    %ecx,%edx       /* overlapping? */
 100         jb      2f
 101         cld                     /* nope, copy forwards. */
 102         movl    %ecx,%edx
 103         shrl    $2,%ecx         /* copy by words */
 104         rep
 105         movsl
 106         movl    %edx,%ecx
 107         andl    $3,%ecx         /* any bytes left? */
 108         rep
 109         movsb
 110         popl    %edi
 111         popl    %esi
 112         ret
 113 2:
 114         addl    %ecx,%edi       /* copy backwards. */
 115         addl    %ecx,%esi
 116         std
 117         movl    %ecx,%edx
 118         andl    $3,%ecx         /* any fractional bytes? */
 119         decl    %edi
 120         decl    %esi
 121         rep
 122         movsb
 123         movl    %edx,%ecx       /* copy remainder by words */
 124         shrl    $2,%ecx
 125         subl    $3,%esi
 126         subl    $3,%edi
 127         rep
 128         movsl
 129         popl    %edi
 130         popl    %esi
 131         cld
 132         ret
 133
 134         COMMPAGE_DESCRIPTOR(bcopy_scalar,_COMM_PAGE_BCOPY,0,0)