tests/lib/test_bitfield.c

   1 /*
   2  * test-bitfield.c
   3  *
   4  * BabelTrace - bitfield test program
   5  *
   6  * Copyright 2010 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; under version 2 of the License.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along
  18  * with this program; if not, write to the Free Software Foundation, Inc.,
  19  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  20  */
  21
  22 #include <babeltrace/bitfield-internal.h>
  23 #include <time.h>
  24 #include <stdlib.h>
  25 #include <stdio.h>
  26
  27 #include <tap/tap.h>
  28
  29 unsigned int glob;
  30
  31 /*
  32  * This function is only declared to show the size of a bitfield write in
  33  * objdump.
  34  */
  35 void fct(void)
  36 {
  37         bt_bitfield_write(&glob, unsigned int, 12, 15, 0x12345678);
  38 }
  39
  40 /* Test array size, in bytes */
  41 #define TEST_LEN 128
  42 #define NR_TESTS 10
  43 #define SIGNED_TEST_DESC_FMT_STR "Writing and reading back 0x%X, signed"
  44 #define UNSIGNED_TEST_DESC_FMT_STR "Writing and reading back 0x%X, unsigned"
  45 #define DIAG_FMT_STR "Failed reading value written \"%s\"-wise, with start=%i" \
  46         " and length=%i. Read %llX"
  47
  48 unsigned int srcrand;
  49
  50 #if defined(__i386) || defined(__x86_64)
  51
  52 static inline int fls(int x)
  53 {
  54         int r;
  55         asm("bsrl %1,%0\n\t"
  56             "cmovzl %2,%0"
  57             : "=&r" (r) : "rm" (x), "rm" (-1));
  58         return r + 1;
  59 }
  60
  61 #elif defined(__PPC__)
  62
  63 static __inline__ int fls(unsigned int x)
  64 {
  65         int lz;
  66
  67         asm ("cntlzw %0,%1" : "=r" (lz) : "r" (x));
  68         return 32 - lz;
  69 }
  70
  71 #else
  72
  73 static int fls(unsigned int x)
  74 {
  75         int r = 32;
  76
  77         if (!x)
  78                 return 0;
  79         if (!(x & 0xFFFF0000U)) {
  80                 x <<= 16;
  81                 r -= 16;
  82         }
  83         if (!(x & 0xFF000000U)) {
  84                 x <<= 8;
  85                 r -= 8;
  86         }
  87         if (!(x & 0xF0000000U)) {
  88                 x <<= 4;
  89                 r -= 4;
  90         }
  91         if (!(x & 0xC0000000U)) {
  92                 x <<= 2;
  93                 r -= 2;
  94         }
  95         if (!(x & 0x80000000U)) {
  96                 x <<= 1;
  97                 r -= 1;
  98         }
  99         return r;
 100 }
 101
 102 #endif
 103
 104 #define print_byte_array(c, len)        \
 105 do {                                    \
 106         unsigned long i;                \
 107                                         \
 108         for (i = 0; i < (len); i++) {   \
 109                 printf("0x%X", (c)[i]); \
 110                 if (i != (len) - 1)     \
 111                         printf(" ");    \
 112         }                               \
 113         printf("\n");                   \
 114 } while (0)
 115
 116 #define init_byte_array(c, len, val)    \
 117 do {                                    \
 118         unsigned long i;                \
 119                                         \
 120         for (i = 0; i < (len); i++)     \
 121                 (c)[i] = (val);         \
 122 } while (0)
 123
 124 #define check_result(ref, val, buffer, typename, start, len,            \
 125                      desc_fmt_str)                                      \
 126 ({                                                                      \
 127         if ((val) != (ref)) {                                           \
 128                 fail(desc_fmt_str, ref);                                \
 129                 diag(DIAG_FMT_STR, #typename, start, len, val);         \
 130                 printf("# ");                                           \
 131                 print_byte_array(buffer, TEST_LEN);                     \
 132         }                                                               \
 133         (val) != (ref);                                                 \
 134 })
 135
 136 void run_test_unsigned(void)
 137 {
 138         unsigned int src, nrbits;
 139         union {
 140                 unsigned char c[TEST_LEN];
 141                 unsigned short s[TEST_LEN/sizeof(unsigned short)];
 142                 unsigned int i[TEST_LEN/sizeof(unsigned int)];
 143                 unsigned long l[TEST_LEN/sizeof(unsigned long)];
 144                 unsigned long long ll[TEST_LEN/sizeof(unsigned long long)];
 145         } target;
 146         unsigned long long readval;
 147         unsigned int s, l;
 148
 149         src = srcrand;
 150         nrbits = fls(src);
 151
 152         for (s = 0; s < CHAR_BIT * TEST_LEN; s++) {
 153                 for (l = nrbits; l < (CHAR_BIT * TEST_LEN) - s; l++) {
 154                         init_byte_array(target.c, TEST_LEN, 0xFF);
 155                         bt_bitfield_write(target.c, unsigned char, s, l, src);
 156                         bt_bitfield_read(target.c, unsigned char, s, l, &readval);
 157                         if (check_result(src, readval, target.c, unsigned char,
 158                                           s, l, UNSIGNED_TEST_DESC_FMT_STR)) {
 159                                 return;
 160                         }
 161
 162                         init_byte_array(target.c, TEST_LEN, 0xFF);
 163                         bt_bitfield_write(target.s, unsigned short, s, l, src);
 164                         bt_bitfield_read(target.c, unsigned char, s, l, &readval);
 165                         if (check_result(src, readval, target.c, unsigned short,
 166                                           s, l, UNSIGNED_TEST_DESC_FMT_STR)) {
 167                                 return;
 168                         }
 169
 170                         init_byte_array(target.c, TEST_LEN, 0xFF);
 171                         bt_bitfield_write(target.i, unsigned int, s, l, src);
 172                         bt_bitfield_read(target.c, unsigned char, s, l, &readval);
 173                         if (check_result(src, readval, target.c, unsigned int,
 174                                            s, l, UNSIGNED_TEST_DESC_FMT_STR)) {
 175                                 return;
 176                         }
 177
 178                         init_byte_array(target.c, TEST_LEN, 0xFF);
 179                         bt_bitfield_write(target.l, unsigned long, s, l, src);
 180                         bt_bitfield_read(target.c, unsigned char, s, l, &readval);
 181                         if (check_result(src, readval, target.c, unsigned long,
 182                                           s, l, UNSIGNED_TEST_DESC_FMT_STR)) {
 183                                 return;
 184                         }
 185
 186                         init_byte_array(target.c, TEST_LEN, 0xFF);
 187                         bt_bitfield_write(target.ll, unsigned long long, s, l, src);
 188                         bt_bitfield_read(target.c, unsigned char, s, l, &readval);
 189                         if (check_result(src, readval, target.c, unsigned long long,
 190                                      s, l, UNSIGNED_TEST_DESC_FMT_STR)) {
 191                                 return;
 192                         }
 193                 }
 194         }
 195
 196         pass(UNSIGNED_TEST_DESC_FMT_STR, src);
 197 }
 198
 199 void run_test_signed(void)
 200 {
 201         int src, nrbits;
 202         union {
 203                 signed char c[TEST_LEN];
 204                 short s[TEST_LEN/sizeof(short)];
 205                 int i[TEST_LEN/sizeof(int)];
 206                 long l[TEST_LEN/sizeof(long)];
 207                 long long ll[TEST_LEN/sizeof(long long)];
 208         } target;
 209         long long readval;
 210         unsigned int s, l;
 211
 212         src = srcrand;
 213         if (src & 0x80000000U)
 214                 nrbits = fls(~src) + 1; /* Find least significant bit conveying sign */
 215         else
 216                 nrbits = fls(src) + 1;  /* Keep sign at 0 */
 217
 218         for (s = 0; s < CHAR_BIT * TEST_LEN; s++) {
 219                 for (l = nrbits; l < (CHAR_BIT * TEST_LEN) - s; l++) {
 220                         init_byte_array(target.c, TEST_LEN, 0x0);
 221                         bt_bitfield_write(target.c, signed char, s, l, src);
 222                         bt_bitfield_read(target.c, signed char, s, l, &readval);
 223                         if (check_result(src, readval, target.c, signed char,
 224                                           s, l, SIGNED_TEST_DESC_FMT_STR)) {
 225                                 return;
 226                         }
 227
 228                         init_byte_array(target.c, TEST_LEN, 0x0);
 229                         bt_bitfield_write(target.s, short, s, l, src);
 230                         bt_bitfield_read(target.c, signed char, s, l, &readval);
 231                         if (check_result(src, readval, target.c, short,
 232                                           s, l, SIGNED_TEST_DESC_FMT_STR)) {
 233                                 return;
 234                         }
 235
 236                         init_byte_array(target.c, TEST_LEN, 0x0);
 237                         bt_bitfield_write(target.i, int, s, l, src);
 238                         bt_bitfield_read(target.c, signed char, s, l, &readval);
 239                         if (check_result(src, readval, target.c, int,
 240                                           s, l, SIGNED_TEST_DESC_FMT_STR)) {
 241                                 return;
 242                         }
 243
 244                         init_byte_array(target.c, TEST_LEN, 0x0);
 245                         bt_bitfield_write(target.l, long, s, l, src);
 246                         bt_bitfield_read(target.c, signed char, s, l, &readval);
 247                         if (check_result(src, readval, target.c, long,
 248                                           s, l, SIGNED_TEST_DESC_FMT_STR)) {
 249                                 return;
 250                         }
 251
 252                         init_byte_array(target.c, TEST_LEN, 0x0);
 253                         bt_bitfield_write(target.ll, long long, s, l, src);
 254                         bt_bitfield_read(target.c, signed char, s, l, &readval);
 255                         if (check_result(src, readval, target.c, long long,
 256                                           s, l, SIGNED_TEST_DESC_FMT_STR)) {
 257                                 return;
 258                         }
 259                 }
 260         }
 261
 262         pass(SIGNED_TEST_DESC_FMT_STR, src);
 263 }
 264
 265 void run_test(void)
 266 {
 267         int i;
 268         plan_tests(NR_TESTS * 2 + 6);
 269
 270         srand(time(NULL));
 271
 272         srcrand = 0;
 273         run_test_unsigned();
 274         srcrand = 0;
 275         run_test_signed();
 276
 277         srcrand = 1;
 278         run_test_unsigned();
 279
 280         srcrand = ~0U;
 281         run_test_unsigned();
 282
 283         srcrand = -1;
 284         run_test_signed();
 285
 286         srcrand = (int)0x80000000U;
 287         run_test_signed();
 288
 289         for (i = 0; i < NR_TESTS; i++) {
 290                 srcrand = rand();
 291                 run_test_unsigned();
 292                 run_test_signed();
 293         }
 294 }
 295
 296 static
 297 int print_encodings(unsigned long src, unsigned int shift, unsigned int len)
 298 {
 299         union {
 300                 unsigned char c[8];
 301                 unsigned short s[4];
 302                 unsigned int i[2];
 303                 unsigned long l[2];
 304                 unsigned long long ll[1];
 305         } target;
 306         unsigned long long readval;
 307
 308         init_byte_array(target.c, 8, 0xFF);
 309         bt_bitfield_write(target.c, unsigned char, shift, len, src);
 310         printf("bytewise\n");
 311         print_byte_array(target.c, 8);
 312
 313         init_byte_array(target.c, 8, 0xFF);
 314         bt_bitfield_write(target.s, unsigned short, shift, len, src);
 315         printf("shortwise\n");
 316         print_byte_array(target.c, 8);
 317
 318         init_byte_array(target.c, 8, 0xFF);
 319         bt_bitfield_write(target.i, unsigned int, shift, len, src);
 320         printf("intwise\n");
 321         print_byte_array(target.c, 8);
 322
 323         init_byte_array(target.c, 8, 0xFF);
 324         bt_bitfield_write(target.l, unsigned long, shift, len, src);
 325         printf("longwise\n");
 326         print_byte_array(target.c, 8);
 327
 328         init_byte_array(target.c, 8, 0xFF);
 329         bt_bitfield_write(target.ll, unsigned long long, shift, len, src);
 330         printf("lluwise\n");
 331         print_byte_array(target.c, 8);
 332
 333         bt_bitfield_read(target.c, unsigned char, shift, len, &readval);
 334         printf("read: %llX\n", readval);
 335         print_byte_array(target.c, 8);
 336
 337         return 0;
 338 }
 339
 340 int main(int argc, char **argv)
 341 {
 342         if (argc > 1) {
 343                 /* Print encodings */
 344                 unsigned long src;
 345                 unsigned int shift, len;
 346
 347                 src = atoi(argv[1]);
 348                 if (argc > 2)
 349                         shift = atoi(argv[2]);
 350                 else
 351                         shift = 12;
 352                 if (argc > 3)
 353                         len = atoi(argv[3]);
 354                 else
 355                         len = 40;
 356                 return print_encodings(src, shift, len);
 357         }
 358
 359         /* Run tap-formated tests */
 360         run_test();
 361         return exit_status();
 362 }