-C Improved\salignment\sof\sfields\sin\sthe\sExpr\sobject\sgives\san\s8-byte\ssize\nreduction\son\s64-bit\smachines.
-D 2012-09-13T19:59:09.165
+C Factor\sout\sthe\scode\sthat\sgenerates\sa\sco-routine\sfor\sevaluating\sthe\sSELECT\non\sthe\sRHS\sof\san\sINSERT\sstatement\sso\sthat\sthe\ssame\scode\scan\spotentially\nbe\sreused\sin\sother\splaces.
+D 2012-09-15T13:29:23.328
F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
F Makefile.in 5f4f26109f9d80829122e0e09f9cda008fa065fb
F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
F src/hash.c a4031441741932da9e7a65bee2b36b5d0e81c073
F src/hash.h 2894c932d84d9f892d4b4023a75e501f83050970
F src/hwtime.h d32741c8f4df852c7d959236615444e2b1063b08
-F src/insert.c b090d0a9fb9ff2dbdeaf66aedccf98cd13b1af60
+F src/insert.c 6e2aa7fbb5d4c5f34d412772751ed0aff0b9e87b
F src/journal.c 552839e54d1bf76fb8f7abe51868b66acacf6a0e
F src/legacy.c a199d7683d60cef73089e892409113e69c23a99f
F src/lempar.c 0ee69fca0be54cd93939df98d2aca4ca46f44416
F src/sqlite.h.in d1071b0fc6de9a0d11392bc01305803122c3ec61
F src/sqlite3.rc fea433eb0a59f4c9393c8e6d76a6e2596b1fe0c0
F src/sqlite3ext.h 6904f4aadf976f95241311fbffb00823075d9477
-F src/sqliteInt.h 03ad3f925f07599cc39a7eebdb250c7f17fd57e6
+F src/sqliteInt.h 0423f0a673e7365827584e86dfbab8c33cf32cf8
F src/sqliteLimit.h 164b0e6749d31e0daa1a4589a169d31c0dec7b3d
F src/status.c 35939e7e03abf1b7577ce311f48f682c40de3208
F src/table.c 2cd62736f845d82200acfa1287e33feb3c15d62e
F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
F tool/warnings.sh fbc018d67fd7395f440c28f33ef0f94420226381
F tool/win/sqlite.vsix 67d8a99aceb56384a81b3f30d6c71743146d2cc9
-P 0ebe7cc57408d6d85910cc976fb8af4436d6e594
-R b742c79022ff08cfe99db98bba004b78
+P 6b252a0d1a78db7bf2d650bafc214ea4064eef9e
+R df7cddb2132aa1a021f32020fc480477
U drh
-Z 3cb58e8f20dd1433c3550c4182838eb5
+Z c609d2d14d939fff56bf9fbc82b9e705
#endif /* SQLITE_OMIT_AUTOINCREMENT */
+/*
+** Generate code for a co-routine that will evaluate a subquery one
+** row at a time.
+**
+** The pSelect parameter is the subquery that the co-routine will evaluation.
+** Information about the location of co-routine and the registers it will use
+** is returned by filling in the pDest object.
+**
+** Registers are allocated as follows:
+**
+** pDest->iSDParm The register holding the next entry-point of the
+** co-routine. Run the co-routine to its next breakpoint
+** by calling "OP_Yield $X" where $X is pDest->iSDParm.
+**
+** pDest->iSDParm+1 The register holding the "completed" flag for the
+** co-routine. This register is 0 if the previous Yield
+** generated a new result row, or 1 if the subquery
+** has completed. If the Yield is called again
+** after this register becomes 1, then the VDBE will
+** halt with an SQLITE_INTERNAL error.
+**
+** pDest->iSdst First result register.
+**
+** pDest->nSdst Number of result registers.
+**
+** This routine handles all of the register allocation and fills in the
+** pDest structure appropriately.
+**
+** Here is a schematic of the generated code assuming that X is the
+** co-routine entry-point register reg[pDest->iSDParm], that EOF is the
+** completed flag reg[pDest->iSDParm+1], and R and S are the range of
+** registers that hold the result set, reg[pDest->iSdst] through
+** reg[pDest->iSdst+pDest->nSdst-1]:
+**
+** X <- A
+** EOF <- 0
+** goto B
+** A: setup for the SELECT
+** loop rows in the SELECT
+** load results into registers R..S
+** yield X
+** end loop
+** cleanup after the SELECT
+** EOF <- 1
+** yield X
+** halt-error
+** B:
+**
+** To use this subroutine, the caller generates code as follows:
+**
+** [ Co-routine generated by this subroutine, shown above ]
+** S: yield X
+** if EOF goto E
+** if skip this row, goto C
+** if terminate loop, goto E
+** deal with this row
+** C: goto S
+** E:
+*/
+int sqlite3CodeCoroutine(Parse *pParse, Select *pSelect, SelectDest *pDest){
+ int regYield; /* Register holding co-routine entry-point */
+ int regEof; /* Register holding co-routine completion flag */
+ int addrTop; /* Top of the co-routine */
+ int j1; /* Jump instruction */
+ int rc; /* Result code */
+ Vdbe *v; /* VDBE under construction */
+
+ regYield = ++pParse->nMem;
+ regEof = ++pParse->nMem;
+ v = sqlite3GetVdbe(pParse);
+ addrTop = sqlite3VdbeCurrentAddr(v);
+ sqlite3VdbeAddOp2(v, OP_Integer, addrTop+2, regYield); /* X <- A */
+ VdbeComment((v, "Co-routine entry point"));
+ sqlite3VdbeAddOp2(v, OP_Integer, 0, regEof); /* EOF <- 0 */
+ VdbeComment((v, "Co-routine completion flag"));
+ sqlite3SelectDestInit(pDest, SRT_Coroutine, regYield);
+ j1 = sqlite3VdbeAddOp2(v, OP_Goto, 0, 0);
+ rc = sqlite3Select(pParse, pSelect, pDest);
+ assert( pParse->nErr==0 || rc );
+ if( pParse->db->mallocFailed && rc==SQLITE_OK ) rc = SQLITE_NOMEM;
+ if( rc ) return rc;
+ sqlite3VdbeAddOp2(v, OP_Integer, 1, regEof); /* EOF <- 1 */
+ sqlite3VdbeAddOp1(v, OP_Yield, regYield); /* yield X */
+ sqlite3VdbeAddOp2(v, OP_Halt, SQLITE_INTERNAL, OE_Abort);
+ VdbeComment((v, "End of coroutine"));
+ sqlite3VdbeJumpHere(v, j1); /* label B: */
+ return rc;
+}
+
+
+
/* Forward declaration */
static int xferOptimization(
Parse *pParse, /* Parser context */
** co-routine is the common header to the 3rd and 4th templates.
*/
if( pSelect ){
- /* Data is coming from a SELECT. Generate code to implement that SELECT
- ** as a co-routine. The code is common to both the 3rd and 4th
- ** templates:
- **
- ** EOF <- 0
- ** X <- A
- ** goto B
- ** A: setup for the SELECT
- ** loop over the tables in the SELECT
- ** load value into register R..R+n
- ** yield X
- ** end loop
- ** cleanup after the SELECT
- ** EOF <- 1
- ** yield X
- ** halt-error
- **
- ** On each invocation of the co-routine, it puts a single row of the
- ** SELECT result into registers dest.iMem...dest.iMem+dest.nMem-1.
- ** (These output registers are allocated by sqlite3Select().) When
- ** the SELECT completes, it sets the EOF flag stored in regEof.
- */
- int rc, j1;
-
- regEof = ++pParse->nMem;
- sqlite3VdbeAddOp2(v, OP_Integer, 0, regEof); /* EOF <- 0 */
- VdbeComment((v, "SELECT eof flag"));
- sqlite3SelectDestInit(&dest, SRT_Coroutine, ++pParse->nMem);
- addrSelect = sqlite3VdbeCurrentAddr(v)+2;
- sqlite3VdbeAddOp2(v, OP_Integer, addrSelect-1, dest.iSDParm);
- j1 = sqlite3VdbeAddOp2(v, OP_Goto, 0, 0);
- VdbeComment((v, "Jump over SELECT coroutine"));
-
- /* Resolve the expressions in the SELECT statement and execute it. */
- rc = sqlite3Select(pParse, pSelect, &dest);
- assert( pParse->nErr==0 || rc );
- if( rc || NEVER(pParse->nErr) || db->mallocFailed ){
- goto insert_cleanup;
- }
- sqlite3VdbeAddOp2(v, OP_Integer, 1, regEof); /* EOF <- 1 */
- sqlite3VdbeAddOp1(v, OP_Yield, dest.iSDParm); /* yield X */
- sqlite3VdbeAddOp2(v, OP_Halt, SQLITE_INTERNAL, OE_Abort);
- VdbeComment((v, "End of SELECT coroutine"));
- sqlite3VdbeJumpHere(v, j1); /* label B: */
+ /* Data is coming from a SELECT. Generate a co-routine to run that
+ ** SELECT. */
+ int rc = sqlite3CodeCoroutine(pParse, pSelect, &dest);
+ if( rc ) goto insert_cleanup;
+ regEof = dest.iSDParm + 1;
regFromSelect = dest.iSdst;
assert( pSelect->pEList );
nColumn = pSelect->pEList->nExpr;
projects / thirdparty / sqlite.git / commitdiff
