Many hyperlinks are disabled.
Use anonymous login
to enable hyperlinks.
Overview
| Comment: | Avoid unnecessary Mem initializations when generating a new sqlite3_stmt object. |
|---|---|
| Downloads: | Tarball | ZIP archive | SQL archive |
| Timelines: | family | ancestors | descendants | both | trunk |
| Files: | files | file ages | folders |
| SHA1: | 47ae1cda8dc255d100aeb8cb90ea4c9e449509be |
| User & Date: | drh 2016-09-30 17:46:44 |
Context
|
2016-09-30
| ||
| 18:35 | Remove unnecessary fields from the Parse object. check-in: 814e41da user: drh tags: trunk | |
| 17:46 | Avoid unnecessary Mem initializations when generating a new sqlite3_stmt object. check-in: 47ae1cda user: drh tags: trunk | |
|
2016-09-29
| ||
| 20:28 | Small size and performance optimization to sqlite3VdbeChangeP5(). check-in: 3c93c8f5 user: drh tags: trunk | |
Changes
Changes to src/vdbe.c.
1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 |
case OP_Null: { /* out2 */
int cnt;
u16 nullFlag;
pOut = out2Prerelease(p, pOp);
cnt = pOp->p3-pOp->p2;
assert( pOp->p3<=(p->nMem+1 - p->nCursor) );
pOut->flags = nullFlag = pOp->p1 ? (MEM_Null|MEM_Cleared) : MEM_Null;
while( cnt>0 ){
pOut++;
memAboutToChange(p, pOut);
sqlite3VdbeMemSetNull(pOut);
pOut->flags = nullFlag;
cnt--;
}
break;
}
/* Opcode: SoftNull P1 * * * *
** Synopsis: r[P1]=NULL
|
> > |
1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 |
case OP_Null: { /* out2 */
int cnt;
u16 nullFlag;
pOut = out2Prerelease(p, pOp);
cnt = pOp->p3-pOp->p2;
assert( pOp->p3<=(p->nMem+1 - p->nCursor) );
pOut->flags = nullFlag = pOp->p1 ? (MEM_Null|MEM_Cleared) : MEM_Null;
pOut->n = 0;
while( cnt>0 ){
pOut++;
memAboutToChange(p, pOut);
sqlite3VdbeMemSetNull(pOut);
pOut->flags = nullFlag;
pOut->n = 0;
cnt--;
}
break;
}
/* Opcode: SoftNull P1 * * * *
** Synopsis: r[P1]=NULL
|
Changes to src/vdbeaux.c.
1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 .... 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 .... 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 .... 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 .... 2103 2104 2105 2106 2107 2108 2109 2110 2111 2112 2113 2114 2115 2116 2117 2118 2119 2120 2121 2122 2123 |
fprintf(pOut, zFormat1, pc,
sqlite3OpcodeName(pOp->opcode), pOp->p1, pOp->p2, pOp->p3, zP4, pOp->p5,
zCom
);
fflush(pOut);
}
#endif
/*
** Release an array of N Mem elements
*/
static void releaseMemArray(Mem *p, int N){
if( p && N ){
Mem *pEnd = &p[N];
................................................................................
if( sqlite3VdbeMemClearAndResize(pMem, 100) ){ /* P4 */
assert( p->db->mallocFailed );
return SQLITE_ERROR;
}
pMem->flags = MEM_Str|MEM_Term;
zP4 = displayP4(pOp, pMem->z, pMem->szMalloc);
if( zP4!=pMem->z ){
sqlite3VdbeMemSetStr(pMem, zP4, -1, SQLITE_UTF8, 0);
}else{
assert( pMem->z!=0 );
pMem->n = sqlite3Strlen30(pMem->z);
pMem->enc = SQLITE_UTF8;
}
pMem++;
................................................................................
** of the prepared statement.
*/
n = ROUND8(sizeof(Op)*p->nOp); /* Bytes of opcode memory used */
x.pSpace = &((u8*)p->aOp)[n]; /* Unused opcode memory */
assert( EIGHT_BYTE_ALIGNMENT(x.pSpace) );
x.nFree = ROUNDDOWN8(pParse->szOpAlloc - n); /* Bytes of unused memory */
assert( x.nFree>=0 );
if( x.nFree>0 ){
memset(x.pSpace, 0, x.nFree);
assert( EIGHT_BYTE_ALIGNMENT(&x.pSpace[x.nFree]) );
}
resolveP2Values(p, &nArg);
p->usesStmtJournal = (u8)(pParse->isMultiWrite && pParse->mayAbort);
if( pParse->explain && nMem<10 ){
nMem = 10;
}
p->expired = 0;
................................................................................
p->aVar = allocSpace(&x, p->aVar, nVar*sizeof(Mem));
p->apArg = allocSpace(&x, p->apArg, nArg*sizeof(Mem*));
p->apCsr = allocSpace(&x, p->apCsr, nCursor*sizeof(VdbeCursor*));
#ifdef SQLITE_ENABLE_STMT_SCANSTATUS
p->anExec = allocSpace(&x, p->anExec, p->nOp*sizeof(i64));
#endif
if( x.nNeeded==0 ) break;
x.pSpace = p->pFree = sqlite3DbMallocZero(db, x.nNeeded);
x.nFree = x.nNeeded;
}while( !db->mallocFailed );
p->nCursor = nCursor;
if( p->aVar ){
p->nVar = (ynVar)nVar;
for(n=0; n<nVar; n++){
p->aVar[n].flags = MEM_Null;
p->aVar[n].db = db;
}
}
p->nzVar = pParse->nzVar;
p->azVar = pParse->azVar;
pParse->nzVar = 0;
pParse->azVar = 0;
if( p->aMem ){
p->nMem = nMem;
for(n=0; n<nMem; n++){
p->aMem[n].flags = MEM_Undefined;
p->aMem[n].db = db;
}
}
p->explain = pParse->explain;
sqlite3VdbeRewind(p);
}
/*
** Close a VDBE cursor and release all the resources that cursor
** happens to hold.
*/
................................................................................
int n;
sqlite3 *db = p->db;
releaseMemArray(p->aColName, p->nResColumn*COLNAME_N);
sqlite3DbFree(db, p->aColName);
n = nResColumn*COLNAME_N;
p->nResColumn = (u16)nResColumn;
p->aColName = pColName = (Mem*)sqlite3DbMallocZero(db, sizeof(Mem)*n );
if( p->aColName==0 ) return;
while( n-- > 0 ){
pColName->flags = MEM_Null;
pColName->db = p->db;
pColName++;
}
}
/*
** Set the name of the idx'th column to be returned by the SQL statement.
** zName must be a pointer to a nul terminated string.
**
** This call must be made after a call to sqlite3VdbeSetNumCols().
|
> > > > > > > > > > > > > > > > < < | < | < < < < < < < < | > > > > < < < > > > > > > | < < | | < < < < |
1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 .... 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 .... 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 .... 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 .... 2113 2114 2115 2116 2117 2118 2119 2120 2121 2122 2123 2124 2125 2126 2127 2128 2129 |
fprintf(pOut, zFormat1, pc,
sqlite3OpcodeName(pOp->opcode), pOp->p1, pOp->p2, pOp->p3, zP4, pOp->p5,
zCom
);
fflush(pOut);
}
#endif
/*
** Initialize an array of N Mem element.
*/
static void initMemArray(Mem *p, int N, sqlite3 *db, u16 flags){
while( (N--)>0 ){
p->db = db;
p->flags = flags;
p->szMalloc = 0;
#ifdef SQLITE_DEBUG
p->pScopyFrom = 0;
#endif
p++;
}
}
/*
** Release an array of N Mem elements
*/
static void releaseMemArray(Mem *p, int N){
if( p && N ){
Mem *pEnd = &p[N];
................................................................................
if( sqlite3VdbeMemClearAndResize(pMem, 100) ){ /* P4 */
assert( p->db->mallocFailed );
return SQLITE_ERROR;
}
pMem->flags = MEM_Str|MEM_Term;
zP4 = displayP4(pOp, pMem->z, pMem->szMalloc);
if( zP4!=pMem->z ){
pMem->n = 0;
sqlite3VdbeMemSetStr(pMem, zP4, -1, SQLITE_UTF8, 0);
}else{
assert( pMem->z!=0 );
pMem->n = sqlite3Strlen30(pMem->z);
pMem->enc = SQLITE_UTF8;
}
pMem++;
................................................................................
** of the prepared statement.
*/
n = ROUND8(sizeof(Op)*p->nOp); /* Bytes of opcode memory used */
x.pSpace = &((u8*)p->aOp)[n]; /* Unused opcode memory */
assert( EIGHT_BYTE_ALIGNMENT(x.pSpace) );
x.nFree = ROUNDDOWN8(pParse->szOpAlloc - n); /* Bytes of unused memory */
assert( x.nFree>=0 );
assert( EIGHT_BYTE_ALIGNMENT(&x.pSpace[x.nFree]) );
resolveP2Values(p, &nArg);
p->usesStmtJournal = (u8)(pParse->isMultiWrite && pParse->mayAbort);
if( pParse->explain && nMem<10 ){
nMem = 10;
}
p->expired = 0;
................................................................................
p->aVar = allocSpace(&x, p->aVar, nVar*sizeof(Mem));
p->apArg = allocSpace(&x, p->apArg, nArg*sizeof(Mem*));
p->apCsr = allocSpace(&x, p->apCsr, nCursor*sizeof(VdbeCursor*));
#ifdef SQLITE_ENABLE_STMT_SCANSTATUS
p->anExec = allocSpace(&x, p->anExec, p->nOp*sizeof(i64));
#endif
if( x.nNeeded==0 ) break;
x.pSpace = p->pFree = sqlite3DbMallocRawNN(db, x.nNeeded);
x.nFree = x.nNeeded;
}while( !db->mallocFailed );
p->nzVar = pParse->nzVar;
p->azVar = pParse->azVar;
pParse->nzVar = 0;
pParse->azVar = 0;
p->explain = pParse->explain;
if( db->mallocFailed==0 ){
p->nCursor = nCursor;
p->nVar = (ynVar)nVar;
initMemArray(p->aVar, nVar, db, MEM_Null);
p->nMem = nMem;
initMemArray(p->aMem, nMem, db, MEM_Undefined);
memset(p->apArg, 0, nArg*sizeof(Mem*));
memset(p->apCsr, 0, nCursor*sizeof(VdbeCursor*));
#ifdef SQLITE_ENABLE_STMT_SCANSTATUS
memset(p->anExec, 0, p->nOp*sizeof(i64));
#endif
}
sqlite3VdbeRewind(p);
}
/*
** Close a VDBE cursor and release all the resources that cursor
** happens to hold.
*/
................................................................................
int n;
sqlite3 *db = p->db;
releaseMemArray(p->aColName, p->nResColumn*COLNAME_N);
sqlite3DbFree(db, p->aColName);
n = nResColumn*COLNAME_N;
p->nResColumn = (u16)nResColumn;
p->aColName = pColName = (Mem*)sqlite3DbMallocRawNN(db, sizeof(Mem)*n );
if( p->aColName==0 ) return;
initMemArray(p->aColName, n, p->db, MEM_Null);
}
/*
** Set the name of the idx'th column to be returned by the SQL statement.
** zName must be a pointer to a nul terminated string.
**
** This call must be made after a call to sqlite3VdbeSetNumCols().
|
Changes to src/vdbemem.c.
289 290 291 292 293 294 295 296 297 298 299 300 301 302 |
assert( !(fg&(MEM_Str|MEM_Blob)) );
assert( fg&(MEM_Int|MEM_Real) );
assert( (pMem->flags&MEM_RowSet)==0 );
assert( EIGHT_BYTE_ALIGNMENT(pMem) );
if( sqlite3VdbeMemClearAndResize(pMem, nByte) ){
return SQLITE_NOMEM_BKPT;
}
/* For a Real or Integer, use sqlite3_snprintf() to produce the UTF-8
** string representation of the value. Then, if the required encoding
** is UTF-16le or UTF-16be do a translation.
**
|
> |
289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 |
assert( !(fg&(MEM_Str|MEM_Blob)) );
assert( fg&(MEM_Int|MEM_Real) );
assert( (pMem->flags&MEM_RowSet)==0 );
assert( EIGHT_BYTE_ALIGNMENT(pMem) );
if( sqlite3VdbeMemClearAndResize(pMem, nByte) ){
pMem->enc = 0;
return SQLITE_NOMEM_BKPT;
}
/* For a Real or Integer, use sqlite3_snprintf() to produce the UTF-8
** string representation of the value. Then, if the required encoding
** is UTF-16le or UTF-16be do a translation.
**
|