diff options
Diffstat (limited to 'newlib/libc/machine/spu/strncpy.c')
-rw-r--r-- | newlib/libc/machine/spu/strncpy.c | 82 |
1 files changed, 82 insertions, 0 deletions
diff --git a/newlib/libc/machine/spu/strncpy.c b/newlib/libc/machine/spu/strncpy.c new file mode 100644 index 000000000..f1c89f571 --- /dev/null +++ b/newlib/libc/machine/spu/strncpy.c @@ -0,0 +1,82 @@ +/* + (C) Copyright 2001,2006, + International Business Machines Corporation, + Sony Computer Entertainment, Incorporated, + Toshiba Corporation, + + All rights reserved. + + Redistribution and use in source and binary forms, with or without + modification, are permitted provided that the following conditions are met: + + * Redistributions of source code must retain the above copyright notice, + this list of conditions and the following disclaimer. + * Redistributions in binary form must reproduce the above copyright + notice, this list of conditions and the following disclaimer in the + documentation and/or other materials provided with the distribution. + * Neither the names of the copyright holders nor the names of their + contributors may be used to endorse or promote products derived from this + software without specific prior written permission. + + THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE + LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + POSSIBILITY OF SUCH DAMAGE. +*/ +#include <spu_intrinsics.h> +#include <stddef.h> +#include <string.h> + +/* Copy the string up to n character from memory area src to + * memory area dest. The memory areas may not overlap. The + * strncpy subroutine returns a pointer to dest. + */ +char * strncpy(char * __restrict__ dest, const char * __restrict__ src, size_t n) +{ + size_t len; + unsigned int cmp, skip, mask; + vec_uchar16 *ptr, data; + vec_uint4 cnt, gt, N; + + N = spu_promote(n, 0); + + /* Determine the string length, including termination character, + * clamped to n characters. + */ + ptr = (vec_uchar16 *)src; + skip = (unsigned int)(ptr) & 15; + mask = 0xFFFF >> skip; + + data = *ptr++; + cmp = spu_extract(spu_gather(spu_cmpeq(data, 0)), 0); + cmp &= mask; + + cnt = spu_cntlz(spu_promote(cmp, 0)); + len = spu_extract(cnt, 0) - (skip + 15); + + gt = spu_cmpgt(spu_promote(len, 0), N); + + while (spu_extract(spu_andc(spu_cmpeq(cnt, 32), gt), 0)) { + data = *ptr++; + len -= 16; + cnt = spu_cntlz(spu_gather(spu_cmpeq(data, 0))); + len += spu_extract(cnt, 0); + + gt = spu_cmpgt(spu_promote(len, 0), N); + } + + /* len = MIN(len, n) + */ + len = spu_extract(spu_sel(spu_promote(len, 0), N, gt), 0); + + /* Perform a memcpy of the resulting length + */ + return ((char *)memcpy((void *)dest, (const void *)src, len)); +} |