| /* Highly optimized version for ix86, x>=6. |
| Copyright (C) 1999, 2000, 2002, 2003 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| Contributed by Ulrich Drepper <drepper@cygnus.com>, 1999. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public |
| License as published by the Free Software Foundation; either |
| version 2.1 of the License, or (at your option) any later version. |
| |
| The GNU C Library is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library; if not, write to the Free |
| Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 02111-1307 USA. */ |
| |
| #include <sysdep.h> |
| #include "asm-syntax.h" |
| #include "bp-sym.h" |
| #include "bp-asm.h" |
| |
| #define PARMS LINKAGE /* no space for saved regs */ |
| #define STR1 PARMS |
| #define STR2 STR1+PTR_SIZE |
| |
| .text |
| ENTRY (BP_SYM (strcmp)) |
| ENTER |
| |
| movl STR1(%esp), %ecx |
| movl STR2(%esp), %edx |
| CHECK_BOUNDS_LOW (%ecx, STR1(%esp)) |
| CHECK_BOUNDS_LOW (%edx, STR2(%esp)) |
| |
| L(oop): movb (%ecx), %al |
| cmpb (%edx), %al |
| jne L(neq) |
| incl %ecx |
| incl %edx |
| testb %al, %al |
| jnz L(oop) |
| |
| xorl %eax, %eax |
| /* when strings are equal, pointers rest one beyond |
| the end of the NUL terminators. */ |
| CHECK_BOUNDS_HIGH (%ecx, STR1(%esp), jbe) |
| CHECK_BOUNDS_HIGH (%edx, STR2(%esp), jbe) |
| LEAVE |
| ret |
| |
| #ifndef __BOUNDED_POINTERS__ |
| L(neq): movl $1, %eax |
| movl $-1, %ecx |
| cmovbl %ecx, %eax |
| #else |
| L(neq): movl $1, %eax |
| ja L(chk) |
| negl %eax |
| /* When strings differ, pointers rest on |
| the unequal characters. */ |
| L(chk): CHECK_BOUNDS_HIGH (%ecx, STR1(%esp), jb) |
| CHECK_BOUNDS_HIGH (%edx, STR2(%esp), jb) |
| #endif |
| |
| LEAVE |
| ret |
| END (BP_SYM (strcmp)) |
| libc_hidden_builtin_def (strcmp) |