| /* strchr with SSE2 with bsf |
| Copyright (C) 2011-2014 Free Software Foundation, Inc. |
| Contributed by Intel Corporation. |
| 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, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #ifndef NOT_IN_libc |
| |
| # include <sysdep.h> |
| |
| # define CFI_PUSH(REG) \ |
| cfi_adjust_cfa_offset (4); \ |
| cfi_rel_offset (REG, 0) |
| |
| # define CFI_POP(REG) \ |
| cfi_adjust_cfa_offset (-4); \ |
| cfi_restore (REG) |
| |
| # define PUSH(REG) pushl REG; CFI_PUSH (REG) |
| # define POP(REG) popl REG; CFI_POP (REG) |
| |
| # define PARMS 8 |
| # define ENTRANCE PUSH(%edi) |
| # define RETURN POP(%edi); ret; CFI_PUSH(%edi); |
| |
| # define STR1 PARMS |
| # define STR2 STR1+4 |
| |
| .text |
| ENTRY (__strchr_sse2_bsf) |
| |
| ENTRANCE |
| mov STR1(%esp), %ecx |
| movd STR2(%esp), %xmm1 |
| |
| pxor %xmm2, %xmm2 |
| mov %ecx, %edi |
| punpcklbw %xmm1, %xmm1 |
| punpcklbw %xmm1, %xmm1 |
| /* ECX has OFFSET. */ |
| and $15, %ecx |
| pshufd $0, %xmm1, %xmm1 |
| je L(loop) |
| |
| /* Handle unaligned string. */ |
| and $-16, %edi |
| movdqa (%edi), %xmm0 |
| pcmpeqb %xmm0, %xmm2 |
| pcmpeqb %xmm1, %xmm0 |
| /* Find where NULL is. */ |
| pmovmskb %xmm2, %edx |
| /* Check if there is a match. */ |
| pmovmskb %xmm0, %eax |
| /* Remove the leading bytes. */ |
| sarl %cl, %edx |
| sarl %cl, %eax |
| test %eax, %eax |
| je L(unaligned_no_match) |
| /* Check which byte is a match. */ |
| bsf %eax, %eax |
| /* Is there a NULL? */ |
| test %edx, %edx |
| je L(unaligned_match) |
| bsf %edx, %edx |
| cmpl %edx, %eax |
| /* Return NULL if NULL comes first. */ |
| ja L(return_null) |
| L(unaligned_match): |
| add %edi, %eax |
| add %ecx, %eax |
| RETURN |
| |
| .p2align 4 |
| L(unaligned_no_match): |
| test %edx, %edx |
| jne L(return_null) |
| pxor %xmm2, %xmm2 |
| |
| add $16, %edi |
| |
| .p2align 4 |
| /* Loop start on aligned string. */ |
| L(loop): |
| movdqa (%edi), %xmm0 |
| pcmpeqb %xmm0, %xmm2 |
| add $16, %edi |
| pcmpeqb %xmm1, %xmm0 |
| pmovmskb %xmm2, %edx |
| pmovmskb %xmm0, %eax |
| or %eax, %edx |
| jnz L(matches) |
| |
| movdqa (%edi), %xmm0 |
| pcmpeqb %xmm0, %xmm2 |
| add $16, %edi |
| pcmpeqb %xmm1, %xmm0 |
| pmovmskb %xmm2, %edx |
| pmovmskb %xmm0, %eax |
| or %eax, %edx |
| jnz L(matches) |
| |
| movdqa (%edi), %xmm0 |
| pcmpeqb %xmm0, %xmm2 |
| add $16, %edi |
| pcmpeqb %xmm1, %xmm0 |
| pmovmskb %xmm2, %edx |
| pmovmskb %xmm0, %eax |
| or %eax, %edx |
| jnz L(matches) |
| |
| movdqa (%edi), %xmm0 |
| pcmpeqb %xmm0, %xmm2 |
| add $16, %edi |
| pcmpeqb %xmm1, %xmm0 |
| pmovmskb %xmm2, %edx |
| pmovmskb %xmm0, %eax |
| or %eax, %edx |
| jnz L(matches) |
| jmp L(loop) |
| |
| L(matches): |
| pmovmskb %xmm2, %edx |
| test %eax, %eax |
| jz L(return_null) |
| bsf %eax, %eax |
| /* There is a match. First find where NULL is. */ |
| test %edx, %edx |
| je L(match) |
| bsf %edx, %ecx |
| /* Check if NULL comes first. */ |
| cmpl %ecx, %eax |
| ja L(return_null) |
| L(match): |
| sub $16, %edi |
| add %edi, %eax |
| RETURN |
| |
| /* Return NULL. */ |
| .p2align 4 |
| L(return_null): |
| xor %eax, %eax |
| RETURN |
| |
| END (__strchr_sse2_bsf) |
| #endif |
