| /* strcpy/stpcpy implementation for i586. |
| Copyright (C) 1997, 2000, 2003, 2005 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997. |
| |
| 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+12 /* space for 3 saved regs */ |
| #define RTN PARMS |
| #define DEST RTN+RTN_SIZE |
| #define SRC DEST+PTR_SIZE |
| |
| #ifndef USE_AS_STPCPY |
| # define STRCPY strcpy |
| #endif |
| |
| #define magic 0xfefefeff |
| |
| .text |
| ENTRY (BP_SYM (STRCPY)) |
| ENTER |
| |
| pushl %edi |
| cfi_adjust_cfa_offset (4) |
| pushl %esi |
| cfi_adjust_cfa_offset (4) |
| pushl %ebx |
| cfi_adjust_cfa_offset (4) |
| |
| movl DEST(%esp), %edi |
| cfi_rel_offset (edi, 8) |
| movl SRC(%esp), %esi |
| cfi_rel_offset (esi, 4) |
| CHECK_BOUNDS_LOW (%edi, DEST(%esp)) |
| CHECK_BOUNDS_LOW (%esi, SRC(%esp)) |
| |
| xorl %eax, %eax |
| leal -1(%esi), %ecx |
| |
| movl $magic, %ebx |
| cfi_rel_offset (ebx, 0) |
| andl $3, %ecx |
| |
| #ifdef PIC |
| call 2f |
| cfi_adjust_cfa_offset (4) |
| 2: popl %edx |
| cfi_adjust_cfa_offset (-4) |
| /* 0xb is the distance between 2: and 1: but we avoid writing |
| 1f-2b because the assembler generates worse code. */ |
| leal 0xb(%edx,%ecx,8), %ecx |
| #else |
| leal 1f(,%ecx,8), %ecx |
| #endif |
| |
| jmp *%ecx |
| |
| .align 8 |
| 1: |
| orb (%esi), %al |
| jz L(end) |
| stosb |
| xorl %eax, %eax |
| incl %esi |
| |
| orb (%esi), %al |
| jz L(end) |
| stosb |
| xorl %eax, %eax |
| incl %esi |
| |
| orb (%esi), %al |
| jz L(end) |
| stosb |
| xorl %eax, %eax |
| incl %esi |
| |
| L(1): movl (%esi), %ecx |
| leal 4(%esi),%esi |
| |
| subl %ecx, %eax |
| addl %ebx, %ecx |
| |
| decl %eax |
| jnc L(3) |
| |
| movl %ecx, %edx |
| xorl %ecx, %eax |
| |
| subl %ebx, %edx |
| andl $~magic, %eax |
| |
| jne L(4) |
| |
| movl %edx, (%edi) |
| leal 4(%edi),%edi |
| |
| jmp L(1) |
| |
| L(3): movl %ecx, %edx |
| |
| subl %ebx, %edx |
| |
| L(4): movb %dl, (%edi) |
| testb %dl, %dl |
| |
| movl %edx, %eax |
| jz L(end2) |
| |
| shrl $16, %eax |
| movb %dh, 1(%edi) |
| #ifdef USE_AS_STPCPY |
| addl $1, %edi |
| #endif |
| |
| cmpb $0, %dh |
| jz L(end2) |
| |
| #ifdef USE_AS_STPCPY |
| movb %al, 1(%edi) |
| addl $1, %edi |
| |
| cmpb $0, %al |
| jz L(end2) |
| |
| addl $1, %edi |
| #else |
| movb %al, 2(%edi) |
| testb %al, %al |
| |
| leal 3(%edi), %edi |
| jz L(end2) |
| #endif |
| |
| L(end): movb %ah, (%edi) |
| |
| L(end2): |
| /* GKM FIXME: check high bounds */ |
| #ifdef USE_AS_STPCPY |
| movl %edi, %eax |
| #else |
| movl DEST(%esp), %eax |
| #endif |
| RETURN_BOUNDED_POINTER (DEST(%esp)) |
| popl %ebx |
| cfi_adjust_cfa_offset (-4) |
| cfi_restore (ebx) |
| popl %esi |
| cfi_adjust_cfa_offset (-4) |
| cfi_restore (esi) |
| popl %edi |
| cfi_adjust_cfa_offset (-4) |
| cfi_restore (edi) |
| |
| LEAVE |
| RET_PTR |
| END (BP_SYM (STRCPY)) |
| #ifndef USE_AS_STPCPY |
| libc_hidden_builtin_def (strcpy) |
| #endif |
