[444] | 1 | /* |
---|
| 2 | (C) Copyright 2008 |
---|
| 3 | International Business Machines Corporation, |
---|
| 4 | All rights reserved. |
---|
| 5 | |
---|
| 6 | Redistribution and use in source and binary forms, with or without |
---|
| 7 | modification, are permitted provided that the following conditions are met: |
---|
| 8 | |
---|
| 9 | * Redistributions of source code must retain the above copyright notice, |
---|
| 10 | this list of conditions and the following disclaimer. |
---|
| 11 | * Redistributions in binary form must reproduce the above copyright |
---|
| 12 | notice, this list of conditions and the following disclaimer in the |
---|
| 13 | documentation and/or other materials provided with the distribution. |
---|
| 14 | * Neither the names of the copyright holders nor the names of their |
---|
| 15 | contributors may be used to endorse or promote products derived from |
---|
| 16 | this software without specific prior written permission. |
---|
| 17 | |
---|
| 18 | THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS |
---|
| 19 | IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED |
---|
| 20 | TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A |
---|
| 21 | PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER |
---|
| 22 | OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
---|
| 23 | EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
---|
| 24 | PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
---|
| 25 | PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF |
---|
| 26 | LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING |
---|
| 27 | NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS |
---|
| 28 | SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
---|
| 29 | */ |
---|
| 30 | |
---|
| 31 | #include <spu_intrinsics.h> |
---|
| 32 | #include "vec_literal.h" |
---|
| 33 | #include <string.h> |
---|
| 34 | |
---|
| 35 | /* |
---|
| 36 | * Supply an inline _strncpy for strcpy/cat and strncpy/cat. Relies on |
---|
| 37 | * checklen and lastzero code being optimized out when they are constant |
---|
| 38 | * zero values. |
---|
| 39 | */ |
---|
| 40 | static inline void * _strncpy(char * __restrict__ dest, const char * |
---|
| 41 | __restrict__ src, size_t maxlen, int |
---|
| 42 | checklen, int lastzero) |
---|
| 43 | { |
---|
| 44 | int adjust, offset, soffset, doffset, shift; |
---|
| 45 | vec_uchar16 *vsrc, *vdest; |
---|
| 46 | vec_uchar16 sdata1, sdata2, sdata, shuffle; |
---|
| 47 | vec_uchar16 mask1, maskzero, cmp0; |
---|
| 48 | vec_uint4 nonzeroes, gathered_cmp, vtmp, vtmp2; |
---|
| 49 | vec_uint4 curlen; /* assumes size_t is 4 bytes */ |
---|
| 50 | const vec_uint4 val31 = { 31, 31, 31, 31 }; |
---|
| 51 | const vec_uint4 val_0123 = { 0x00010203, 0x04050607, 0x08090A0B, 0x0C0D0E0F }; |
---|
| 52 | const vec_uchar16 all_ones = { 0xff,0xff,0xff,0xff, 0xff,0xff,0xff,0xff, |
---|
| 53 | 0xff,0xff,0xff,0xff, 0xff,0xff,0xff,0xff }; |
---|
| 54 | |
---|
| 55 | vsrc = (vec_uchar16 *) src; |
---|
| 56 | vdest = (vec_uchar16 *) dest; |
---|
| 57 | soffset = (int) src & 15; |
---|
| 58 | doffset = (int) dest & 15; |
---|
| 59 | |
---|
| 60 | if (checklen) { |
---|
| 61 | /* |
---|
| 62 | * Set curlen so it is the number of bytes we would copy if starting |
---|
| 63 | * from vdest & ~0xf. |
---|
| 64 | * |
---|
| 65 | * curlen could probably be replaced by comparing vdest plus some |
---|
| 66 | * offset to dest + maxlen, that would help mainly in the while loop |
---|
| 67 | * but would lose only one instruction (the curlen -= 16). |
---|
| 68 | */ |
---|
| 69 | curlen = spu_splats((unsigned int) (maxlen + doffset)); |
---|
| 70 | } |
---|
| 71 | |
---|
| 72 | /* |
---|
| 73 | * Setup a shuffle pattern to align the source string with the |
---|
| 74 | * alignment of the destination string. |
---|
| 75 | */ |
---|
| 76 | vtmp = spu_cmpgt(spu_promote(doffset, 0), spu_promote(soffset, 0)); |
---|
| 77 | adjust = spu_extract(vtmp, 0); |
---|
| 78 | offset = soffset - doffset; |
---|
| 79 | offset += adjust & 16; |
---|
| 80 | shuffle = spu_splats((unsigned char) offset); |
---|
| 81 | shuffle = (vec_uchar16) spu_add((vec_uint4) shuffle, val_0123); |
---|
| 82 | |
---|
| 83 | vsrc += adjust; |
---|
| 84 | sdata1 = *vsrc++; |
---|
| 85 | sdata2 = *vsrc++; |
---|
| 86 | sdata = spu_shuffle(sdata1, sdata2, shuffle); |
---|
| 87 | |
---|
| 88 | /* |
---|
| 89 | * mask out leading bytes |
---|
| 90 | */ |
---|
| 91 | mask1 = spu_rlmaskqwbyte(all_ones, -doffset); |
---|
| 92 | |
---|
| 93 | cmp0 = spu_and(mask1, spu_cmpeq(sdata, 0)); |
---|
| 94 | nonzeroes = spu_cntlz(spu_gather(cmp0)); |
---|
| 95 | /* |
---|
| 96 | * First element of nonzeroes - 15 is the number of leading non-zero |
---|
| 97 | * bytes plus 1 for the zero byte. |
---|
| 98 | */ |
---|
| 99 | if (checklen) { |
---|
| 100 | vtmp = spu_add(curlen, 15); |
---|
| 101 | vtmp2 = spu_cmpgt(nonzeroes, vtmp); |
---|
| 102 | nonzeroes = spu_sel(nonzeroes, vtmp, vtmp2); |
---|
| 103 | } |
---|
| 104 | |
---|
| 105 | vtmp = spu_cmpgt(nonzeroes, val31); |
---|
| 106 | /* |
---|
| 107 | * Note: using immediate (constant 31) vs a vector value (val31) does |
---|
| 108 | * not give different results, and we have to have a vector val31 for |
---|
| 109 | * the spu_sel below, so use val31 everywhere. |
---|
| 110 | */ |
---|
| 111 | vtmp = spu_sel(nonzeroes, val31, vtmp); |
---|
| 112 | /* |
---|
| 113 | * So vtmp is now min(nonzeroes, 31), the number of bytes + 16 that we |
---|
| 114 | * want to copy from the first 16 bytes of the source. |
---|
| 115 | */ |
---|
| 116 | if (checklen) { |
---|
| 117 | curlen = spu_sub(vtmp, curlen); |
---|
| 118 | curlen = spu_sub(15, curlen); |
---|
| 119 | } |
---|
| 120 | |
---|
| 121 | /* |
---|
| 122 | * We want a right shift 0xff with fill by ones of (vtmp - 15) bytes, but |
---|
| 123 | * that doesn't exist so use spu_slqwbyte and vtmp all ones left by |
---|
| 124 | * (31 - vtmp). Note: this can also use spu_rlqwbytebc with spu_rlqw. |
---|
| 125 | */ |
---|
| 126 | shift = spu_extract(spu_sub(val31, vtmp), 0); |
---|
| 127 | maskzero = spu_slqwbyte(all_ones, shift); |
---|
| 128 | maskzero = spu_and(mask1, maskzero); |
---|
| 129 | *vdest = spu_sel(*vdest, sdata, maskzero); |
---|
| 130 | |
---|
| 131 | vtmp = spu_cmpgt(nonzeroes, val31); |
---|
| 132 | if (checklen) { |
---|
| 133 | vtmp2 = spu_cmpgt(curlen, 0); |
---|
| 134 | vtmp = spu_and(vtmp, vtmp2); |
---|
| 135 | } |
---|
| 136 | if (spu_extract(vtmp, 0)) { |
---|
| 137 | sdata1 = sdata2; |
---|
| 138 | sdata2 = *vsrc++; |
---|
| 139 | sdata = spu_shuffle(sdata1, sdata2, shuffle); |
---|
| 140 | cmp0 = spu_cmpeq(sdata, 0); |
---|
| 141 | gathered_cmp = spu_gather(cmp0); |
---|
| 142 | /* |
---|
| 143 | * Copy 16 bytes at a time. |
---|
| 144 | */ |
---|
| 145 | while ((spu_extract(gathered_cmp, 0) == 0) && |
---|
| 146 | (!checklen || (spu_extract(curlen, 0) > 15))) { |
---|
| 147 | if (checklen) |
---|
| 148 | curlen = spu_add(curlen, -16); |
---|
| 149 | *++vdest = sdata; |
---|
| 150 | sdata1 = sdata2; |
---|
| 151 | sdata2 = *vsrc++; |
---|
| 152 | sdata = spu_shuffle(sdata1, sdata2, shuffle); |
---|
| 153 | cmp0 = spu_cmpeq(sdata, 0); |
---|
| 154 | gathered_cmp = spu_gather(cmp0); |
---|
| 155 | } |
---|
| 156 | /* |
---|
| 157 | * Copy 0 to 15 trailing bytes, either up to the smaller of curlen or |
---|
| 158 | * the number of non-zero bytes. |
---|
| 159 | */ |
---|
| 160 | nonzeroes = spu_cntlz(gathered_cmp); |
---|
| 161 | if (checklen) { |
---|
| 162 | vtmp = spu_add(curlen, 15); |
---|
| 163 | vtmp2 = spu_cmpgt(nonzeroes, vtmp); |
---|
| 164 | nonzeroes = spu_sel(nonzeroes, vtmp, vtmp2); |
---|
| 165 | curlen = spu_sub(nonzeroes, curlen); |
---|
| 166 | curlen = spu_sub(15, curlen); |
---|
| 167 | } |
---|
| 168 | shift = spu_extract(spu_sub(val31, nonzeroes), 0); |
---|
| 169 | maskzero = spu_slqwbyte(all_ones, shift); |
---|
| 170 | ++vdest; |
---|
| 171 | *vdest = spu_sel(*vdest, sdata, maskzero); |
---|
| 172 | } |
---|
| 173 | |
---|
| 174 | if (checklen && lastzero) { |
---|
| 175 | /* |
---|
| 176 | * For strncat. |
---|
| 177 | */ |
---|
| 178 | dest[maxlen - spu_extract(curlen, 0)] = '\0'; |
---|
| 179 | } |
---|
| 180 | |
---|
| 181 | /* Pad null bytes if the length of the "src" is less than "n" (strncpy). */ |
---|
| 182 | if (checklen && !lastzero && spu_extract(curlen, 0)) |
---|
| 183 | memset(dest + maxlen - spu_extract(curlen, 0), 0, spu_extract(curlen, 0)); |
---|
| 184 | return (dest); |
---|
| 185 | } |
---|