sysdeps/i386/i686/multiarch/memcmp.S

   1 /* Multiple versions of memcmp
   2    Copyright (C) 2010, 2012 Free Software Foundation, Inc.
   3    Contributed by Intel Corporation.
   4    This file is part of the GNU C Library.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2.1 of the License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library; if not, see
  18    <http://www.gnu.org/licenses/>.  */
  19
  20 #include <sysdep.h>
  21 #include <init-arch.h>
  22
  23 /* Define multiple versions only for the definition in libc. */
  24 #ifndef NOT_IN_libc
  25 # ifdef SHARED
  26         .text
  27 ENTRY(memcmp)
  28         .type   memcmp, @gnu_indirect_function
  29         pushl   %ebx
  30         cfi_adjust_cfa_offset (4)
  31         cfi_rel_offset (ebx, 0)
  32         LOAD_PIC_REG(bx)
  33         cmpl    $0, KIND_OFFSET+__cpu_features@GOTOFF(%ebx)
  34         jne     1f
  35         call    __init_cpu_features
  36 1:      leal    __memcmp_ia32@GOTOFF(%ebx), %eax
  37         testl   $bit_SSSE3, CPUID_OFFSET+index_SSSE3+__cpu_features@GOTOFF(%ebx)
  38         jz      2f
  39         leal    __memcmp_ssse3@GOTOFF(%ebx), %eax
  40         testl   $bit_SSE4_2, CPUID_OFFSET+index_SSE4_2+__cpu_features@GOTOFF(%ebx)
  41         jz      2f
  42         leal    __memcmp_sse4_2@GOTOFF(%ebx), %eax
  43 2:      popl    %ebx
  44         cfi_adjust_cfa_offset (-4)
  45         cfi_restore (ebx)
  46         ret
  47 END(memcmp)
  48 # else
  49         .text
  50 ENTRY(memcmp)
  51         .type   memcmp, @gnu_indirect_function
  52         cmpl    $0, KIND_OFFSET+__cpu_features
  53         jne     1f
  54         call    __init_cpu_features
  55 1:      leal    __memcmp_ia32, %eax
  56         testl   $bit_SSSE3, CPUID_OFFSET+index_SSSE3+__cpu_features
  57         jz      2f
  58         leal    __memcmp_ssse3, %eax
  59         testl   $bit_SSE4_2, CPUID_OFFSET+index_SSE4_2+__cpu_features
  60         jz      2f
  61         leal    __memcmp_sse4_2, %eax
  62 2:      ret
  63 END(memcmp)
  64 # endif
  65
  66 # undef ENTRY
  67 # define ENTRY(name) \
  68         .type __memcmp_ia32, @function; \
  69         .p2align 4; \
  70         __memcmp_ia32: cfi_startproc; \
  71         CALL_MCOUNT
  72 # undef END
  73 # define END(name) \
  74         cfi_endproc; .size __memcmp_ia32, .-__memcmp_ia32
  75
  76 # ifdef SHARED
  77 #  undef libc_hidden_builtin_def
  78 /* IFUNC doesn't work with the hidden functions in shared library since
  79    they will be called without setting up EBX needed for PLT which is
  80    used by IFUNC.  */
  81 #  define libc_hidden_builtin_def(name) \
  82         .globl __GI_memcmp; __GI_memcmp = __memcmp_ia32
  83 # endif
  84 #endif
  85
  86 #include "../memcmp.S"