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Overview
Comment: | Make use of the __buildin_OP_overflow() functions from GCC when doing 64-bit signed integer arithmetic. |
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Downloads: | Tarball | ZIP archive |
Timelines: | family | ancestors | descendants | both | gnu-safe-math |
Files: | files | file ages | folders |
SHA1: |
82cbebb8ee4484f13e5f48d305e20e73 |
User & Date: | drh 2017-01-03 17:33:43.523 |
Context
2017-01-03
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18:05 | Use the GCC built-in __sync_fetch_and_sub() to make the sqlite3StatusDown() routine atomic, and thereby avoid some mutexing. (check-in: f69ce75b3d user: drh tags: gnu-safe-math) | |
17:33 | Make use of the __buildin_OP_overflow() functions from GCC when doing 64-bit signed integer arithmetic. (check-in: 82cbebb8ee user: drh tags: gnu-safe-math) | |
14:45 | Add the experimental affinity() SQL function when SQLITE_DEBUG is defined. (check-in: bed0eaa5f5 user: drh tags: trunk) | |
Changes
Changes to src/util.c.
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1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 | /* ** Attempt to add, substract, or multiply the 64-bit signed value iB against ** the other 64-bit signed integer at *pA and store the result in *pA. ** Return 0 on success. Or if the operation would have resulted in an ** overflow, leave *pA unchanged and return 1. */ int sqlite3AddInt64(i64 *pA, i64 iB){ i64 iA = *pA; testcase( iA==0 ); testcase( iA==1 ); testcase( iB==-1 ); testcase( iB==0 ); if( iB>=0 ){ testcase( iA>0 && LARGEST_INT64 - iA == iB ); testcase( iA>0 && LARGEST_INT64 - iA == iB - 1 ); if( iA>0 && LARGEST_INT64 - iA < iB ) return 1; }else{ testcase( iA<0 && -(iA + LARGEST_INT64) == iB + 1 ); testcase( iA<0 && -(iA + LARGEST_INT64) == iB + 2 ); if( iA<0 && -(iA + LARGEST_INT64) > iB + 1 ) return 1; } *pA += iB; return 0; } int sqlite3SubInt64(i64 *pA, i64 iB){ testcase( iB==SMALLEST_INT64+1 ); if( iB==SMALLEST_INT64 ){ testcase( (*pA)==(-1) ); testcase( (*pA)==0 ); if( (*pA)>=0 ) return 1; *pA -= iB; return 0; }else{ return sqlite3AddInt64(pA, -iB); } } int sqlite3MulInt64(i64 *pA, i64 iB){ i64 iA = *pA; if( iB>0 ){ if( iA>LARGEST_INT64/iB ) return 1; if( iA<SMALLEST_INT64/iB ) return 1; }else if( iB<0 ){ if( iA>0 ){ if( iB<SMALLEST_INT64/iA ) return 1; }else if( iA<0 ){ if( iB==SMALLEST_INT64 ) return 1; if( iA==SMALLEST_INT64 ) return 1; if( -iA>LARGEST_INT64/-iB ) return 1; } } *pA = iA*iB; return 0; } /* ** Compute the absolute value of a 32-bit signed integer, of possible. Or ** if the integer has a value of -2147483648, return +2147483647 */ int sqlite3AbsInt32(int x){ | > > > > > > > > > > > > > > > | 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 | /* ** Attempt to add, substract, or multiply the 64-bit signed value iB against ** the other 64-bit signed integer at *pA and store the result in *pA. ** Return 0 on success. Or if the operation would have resulted in an ** overflow, leave *pA unchanged and return 1. */ int sqlite3AddInt64(i64 *pA, i64 iB){ #if !defined(SQLITE_DISABLE_INTRINSIC) \ && defined(__GNUC__) && GCC_VERSION>=5004000 return __builtin_add_overflow(*pA, iB, pA); #else i64 iA = *pA; testcase( iA==0 ); testcase( iA==1 ); testcase( iB==-1 ); testcase( iB==0 ); if( iB>=0 ){ testcase( iA>0 && LARGEST_INT64 - iA == iB ); testcase( iA>0 && LARGEST_INT64 - iA == iB - 1 ); if( iA>0 && LARGEST_INT64 - iA < iB ) return 1; }else{ testcase( iA<0 && -(iA + LARGEST_INT64) == iB + 1 ); testcase( iA<0 && -(iA + LARGEST_INT64) == iB + 2 ); if( iA<0 && -(iA + LARGEST_INT64) > iB + 1 ) return 1; } *pA += iB; return 0; #endif } int sqlite3SubInt64(i64 *pA, i64 iB){ #if !defined(SQLITE_DISABLE_INTRINSIC) \ && defined(__GNUC__) && GCC_VERSION>=5004000 return __builtin_sub_overflow(*pA, iB, pA); #else testcase( iB==SMALLEST_INT64+1 ); if( iB==SMALLEST_INT64 ){ testcase( (*pA)==(-1) ); testcase( (*pA)==0 ); if( (*pA)>=0 ) return 1; *pA -= iB; return 0; }else{ return sqlite3AddInt64(pA, -iB); } #endif } int sqlite3MulInt64(i64 *pA, i64 iB){ #if !defined(SQLITE_DISABLE_INTRINSIC) \ && defined(__GNUC__) && GCC_VERSION>=5004000 return __builtin_mul_overflow(*pA, iB, pA); #else i64 iA = *pA; if( iB>0 ){ if( iA>LARGEST_INT64/iB ) return 1; if( iA<SMALLEST_INT64/iB ) return 1; }else if( iB<0 ){ if( iA>0 ){ if( iB<SMALLEST_INT64/iA ) return 1; }else if( iA<0 ){ if( iB==SMALLEST_INT64 ) return 1; if( iA==SMALLEST_INT64 ) return 1; if( -iA>LARGEST_INT64/-iB ) return 1; } } *pA = iA*iB; return 0; #endif } /* ** Compute the absolute value of a 32-bit signed integer, of possible. Or ** if the integer has a value of -2147483648, return +2147483647 */ int sqlite3AbsInt32(int x){ |
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