diff options
Diffstat (limited to 'sysdeps/x86_64/strrchr.S')
| -rw-r--r-- | sysdeps/x86_64/strrchr.S | 81 |
1 files changed, 81 insertions, 0 deletions
diff --git a/sysdeps/x86_64/strrchr.S b/sysdeps/x86_64/strrchr.S new file mode 100644 index 0000000000..c75b485ca3 --- /dev/null +++ b/sysdeps/x86_64/strrchr.S @@ -0,0 +1,81 @@ +/* strrchr (str, ch) -- Return pointer to last occurrence of CH in STR. + For AMD x86-64. + Copyright (C) 2009 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + 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> + + + .text +ENTRY (strrchr) + movd %esi, %xmm1 + movq %rdi, %rcx + punpcklbw %xmm1, %xmm1 + andq $~15, %rdi + pxor %xmm2, %xmm2 + punpcklbw %xmm1, %xmm1 + orl $0xffffffff, %esi + movdqa (%rdi), %xmm0 + pshufd $0, %xmm1, %xmm1 + subq %rdi, %rcx + movdqa %xmm0, %xmm3 + leaq 16(%rdi), %rdi + pcmpeqb %xmm1, %xmm0 + pcmpeqb %xmm2, %xmm3 + shl %cl, %esi + pmovmskb %xmm0, %edx + pmovmskb %xmm3, %ecx + andl %esi, %edx + andl %esi, %ecx + xorl %eax, %eax + movl %edx, %esi + orl %ecx, %esi + jnz 1f + +2: movdqa (%rdi), %xmm0 + leaq 16(%rdi), %rdi + movdqa %xmm0, %xmm3 + pcmpeqb %xmm1, %xmm0 + pcmpeqb %xmm2, %xmm3 + pmovmskb %xmm0, %edx + pmovmskb %xmm3, %ecx + movl %edx, %esi + orl %ecx, %esi + jz 2b + +1: bsfl %ecx, %r9d + movl $0xffffffff, %r8d + movl $31, %ecx + jnz 5f + + bsrl %edx, %edx + jz 2b + leaq -16(%rdi,%rdx), %rax + jmp 2b + +5: subl %r9d, %ecx + shrl %cl, %r8d + andl %r8d, %edx + bsrl %edx, %edx + jz 4f + leaq -16(%rdi,%rdx), %rax +4: ret +END (strrchr) + +weak_alias (strrchr, rindex) +libc_hidden_builtin_def (strrchr) |