sysdeps/s390/s390-64/memcmp.S

   1 /* memcmp - compare two memory blocks.  64 bit S/390 version.
   2    Copyright (C) 2012-2015 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19
  20 #include <sysdep.h>
  21 #include "asm-syntax.h"
  22
  23 /* INPUT PARAMETERS
  24      %r2 = address of first memory area
  25      %r3 = address of second memory area
  26      %r4 = number of bytes to compare.  */
  27
  28        .text
  29 #ifdef USE_MULTIARCH
  30 ENTRY(__memcmp_default)
  31 #else
  32 ENTRY(memcmp)
  33 #endif
  34         .machine "z900"
  35         ltgr    %r4,%r4
  36         je      .L_Z900_4
  37         aghi    %r4,-1
  38         srlg    %r1,%r4,8
  39         ltgr    %r1,%r1
  40         jne     .L_Z900_12
  41 .L_Z900_3:
  42         larl    %r1,.L_Z900_15
  43         ex      %r4,0(%r1)
  44 .L_Z900_4:
  45         ipm     %r2
  46         sllg    %r2,%r2,34
  47         srag    %r2,%r2,62
  48         br      %r14
  49 .L_Z900_12:
  50         clc     0(256,%r3),0(%r2)
  51         jne     .L_Z900_4
  52         la      %r3,256(%r3)
  53         la      %r2,256(%r2)
  54         brctg   %r1,.L_Z900_12
  55         j       .L_Z900_3
  56 .L_Z900_15:
  57         clc     0(1,%r3),0(%r2)
  58 #ifdef USE_MULTIARCH
  59 END(__memcmp_default)
  60 #else
  61 END(memcmp)
  62 libc_hidden_builtin_def (memcmp)
  63 weak_alias (memcmp, bcmp)
  64 #endif