sysdeps/i386/i686/multiarch/strchr.S

   1 /* Multiple versions of strchr
   2    All versions must be listed in ifunc-impl-list.c.
   3    Copyright (C) 2011-2015 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         .text
  26 ENTRY(strchr)
  27         .type   strchr, @gnu_indirect_function
  28         pushl   %ebx
  29         cfi_adjust_cfa_offset (4)
  30         cfi_rel_offset (ebx, 0)
  31         LOAD_PIC_REG(bx)
  32         cmpl    $0, KIND_OFFSET+__cpu_features@GOTOFF(%ebx)
  33         jne     1f
  34         call    __init_cpu_features
  35 1:      leal    __strchr_ia32@GOTOFF(%ebx), %eax
  36         testl   $bit_SSE2, CPUID_OFFSET+index_SSE2+__cpu_features@GOTOFF(%ebx)
  37         jz      2f
  38         leal    __strchr_sse2_bsf@GOTOFF(%ebx), %eax
  39         testl   $bit_Slow_BSF, FEATURE_OFFSET+index_Slow_BSF+__cpu_features@GOTOFF(%ebx)
  40         jz      2f
  41         leal    __strchr_sse2@GOTOFF(%ebx), %eax
  42 2:      popl    %ebx
  43         cfi_adjust_cfa_offset (-4);
  44         cfi_restore (ebx)
  45         ret
  46 END(strchr)
  47
  48 # undef ENTRY
  49 # define ENTRY(name) \
  50         .type __strchr_ia32, @function; \
  51         .globl __strchr_ia32; \
  52         .p2align 4; \
  53         __strchr_ia32: cfi_startproc; \
  54         CALL_MCOUNT
  55 # undef END
  56 # define END(name) \
  57         cfi_endproc; .size __strchr_ia32, .-__strchr_ia32
  58 # undef libc_hidden_builtin_def
  59 /* IFUNC doesn't work with the hidden functions in shared library since
  60    they will be called without setting up EBX needed for PLT which is
  61    used by IFUNC.  */
  62 # define libc_hidden_builtin_def(name) \
  63         .globl __GI_strchr; __GI_strchr = __strchr_ia32
  64 #endif
  65
  66 #include "../../i586/strchr.S"