sysdeps/i386/i686/multiarch/memrchr.S

   1 /* Multiple versions of memrchr
   2    All versions must be listed in ifunc-impl-list.c.
   3    Copyright (C) 2011-2014 Free Software Foundation, Inc.
   4    Contributed by Intel Corporation.
   5    This file is part of the GNU C Library.
   6
   7    The GNU C Library is free software; you can redistribute it and/or
   8    modify it under the terms of the GNU Lesser General Public
   9    License as published by the Free Software Foundation; either
  10    version 2.1 of the License, or (at your option) any later version.
  11
  12    The GNU C Library is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15    Lesser General Public License for more details.
  16
  17    You should have received a copy of the GNU Lesser General Public
  18    License along with the GNU C Library; if not, see
  19    <http://www.gnu.org/licenses/>.  */
  20
  21 #include <sysdep.h>
  22 #include <init-arch.h>
  23
  24 #if IS_IN (libc)
  25 # define CFI_POP(REG) \
  26         cfi_adjust_cfa_offset (-4); \
  27         cfi_restore (REG)
  28
  29 # define CFI_PUSH(REG) \
  30         cfi_adjust_cfa_offset (4); \
  31         cfi_rel_offset (REG, 0)
  32
  33         .text
  34 ENTRY(__memrchr)
  35         .type   __memrchr, @gnu_indirect_function
  36         pushl   %ebx
  37         CFI_PUSH (%ebx)
  38         LOAD_PIC_REG(bx)
  39         cmpl    $0, KIND_OFFSET+__cpu_features@GOTOFF(%ebx)
  40         jne     1f
  41         call    __init_cpu_features
  42
  43 1:      testl   $bit_SSE2, CPUID_OFFSET+index_SSE2+__cpu_features@GOTOFF(%ebx)
  44         jz      2f
  45         testl   $bit_Slow_BSF, FEATURE_OFFSET+index_Slow_BSF+__cpu_features@GOTOFF(%ebx)
  46         jz      3f
  47
  48         leal    __memrchr_sse2@GOTOFF(%ebx), %eax
  49         popl    %ebx
  50         CFI_POP (%ebx)
  51         ret
  52
  53         CFI_PUSH (%ebx)
  54
  55 2:      leal    __memrchr_ia32@GOTOFF(%ebx), %eax
  56         popl    %ebx
  57         CFI_POP (%ebx)
  58         ret
  59
  60         CFI_PUSH (%ebx)
  61
  62 3:      leal    __memrchr_sse2_bsf@GOTOFF(%ebx), %eax
  63         popl    %ebx
  64         CFI_POP (%ebx)
  65         ret
  66 END(__memrchr)
  67
  68 weak_alias(__memrchr, memrchr)
  69 #endif