Alternative implementation of exprCompareVariable(). Need to run tests on

both this branch and the original to see which one to go with.

FossilOrigin-Name: b959c6297c151150ea2dca24aa1f68f3bd76dd6620eb6c03f8dfa59fdd5c13b2

manifest

@@ -1,5 +1,5 @@
-C Make\sthe\squery\splanners\suse\sof\spartial\sindexes\sbased\son\sbound\svariables\nresponsive\sto\sthe\sSQLITE_DBCONFIG_ENABLE_QPSG\ssetting.
+C Alternative\simplementation\sof\sexprCompareVariable().\s\sNeed\sto\srun\stests\son\nboth\sthis\sbranch\sand\sthe\soriginal\sto\ssee\swhich\sone\sto\sgo\swith.
-D 2017-06-28T18:25:03.706
+D 2017-06-28T21:47:16.657
 F Makefile.in 1cc758ce3374a32425e4d130c2fe7b026b20de5b8843243de75f087c0a2661fb
 F Makefile.linux-gcc 7bc79876b875010e8c8f9502eb935ca92aa3c434
 F Makefile.msc 8eeb80162074004e906b53d7340a12a14c471a83743aab975947e95ce061efcc
@@ -359,7 +359,7 @@ F src/ctime.c e9a6db1321c2353fe922533f202b85abb3084cdf569450abcabf55e21e104550
 F src/date.c cc42a41c7422389860d40419a5e3bce5eaf6e7835c3ba2677751dc653550a5c7
 F src/dbstat.c 19ee7a4e89979d4df8e44cfac7a8f905ec89b77d
 F src/delete.c 3213547e97b676c6fa79948b7a9ede4801ea04a01a2043241deafedf132ecf5d
-F src/expr.c 9aea9dbac1169c5cda3ee5d288b9e6c25de597a38023f8104406e0312145ca8d
+F src/expr.c 8281b9e5b88862176862c614acda20fdeb85c20143c5125cee4efd2893c1a64e
 F src/fault.c 460f3e55994363812d9d60844b2a6de88826e007
 F src/fkey.c 5ff2c895fe087756d8085dc1a9bc229b5670e2a65c3929dd87c71e43649af333
 F src/func.c 9d52522cc8ae7f5cdadfe14594262f1618bc1f86083c4cd6da861b4cf5af6174
@@ -1585,7 +1585,10 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 8f63c5863231eba7f853f9587b58a81102c31708402fa9962a6e91aa622fad13
+P a934dd14ac55177ac541423f4a077484bb3b461b60c9c2e88d067cca922fa2bc
-R c0bca5815e0b14a60d8900b0ad5f06a7
+R d8af740d34bab1193c95ada6cd028712
+T *branch * partial-index-variables-v2
+T *sym-partial-index-variables-v2 *
+T -sym-partial-index-variables *
 U drh
-Z afcf7a655c64b8f5d4a7cb72e9e49496
+Z 929717708efb4b9fc1714d496de51de5

manifest.uuid

@@ -1 +1 @@
-a934dd14ac55177ac541423f4a077484bb3b461b60c9c2e88d067cca922fa2bc
+b959c6297c151150ea2dca24aa1f68f3bd76dd6620eb6c03f8dfa59fdd5c13b2

src/expr.c

@@ -4675,29 +4675,19 @@ void sqlite3ExprIfFalseDup(Parse *pParse, Expr *pExpr, int dest,int jumpIfNull){
 */
 static int exprCompareVariable(Parse *pParse, Expr *pVar, Expr *pExpr){
   int res = 0;
-  int iVar = pVar->iColumn;
+  int iVar;
-  Expr *p = pExpr;
+  sqlite3_value *pL, *pR = 0;
   
-  while( p->op==TK_UMINUS ) p = p->pLeft;
-  if( p->op==TK_NULL  || p->op==TK_INTEGER 
-   || p->op==TK_FLOAT || p->op==TK_STRING 
-   || p->op==TK_BLOB 
-  ){
-    sqlite3VdbeSetVarmask(pParse->pVdbe, iVar);
-    sqlite3_value *pL;
-    pL = sqlite3VdbeGetBoundValue(pParse->pReprepare, iVar, SQLITE_AFF_BLOB);
-    if( pL ){
-      sqlite3_value *pR = 0;
   sqlite3ValueFromExpr(pParse->db, pExpr, SQLITE_UTF8, SQLITE_AFF_BLOB, &pR);
-      assert( pR || pParse->db->mallocFailed );
+  if( pR ){
-      if( pR && 0==sqlite3MemCompare(pL, pR, 0) ){
+    iVar = pVar->iColumn;
+    sqlite3VdbeSetVarmask(pParse->pVdbe, iVar);
+    pL = sqlite3VdbeGetBoundValue(pParse->pReprepare, iVar, SQLITE_AFF_BLOB);
+    if( pL && 0==sqlite3MemCompare(pL, pR, 0) ){
       res = 1;
     }
     sqlite3ValueFree(pR);
     sqlite3ValueFree(pL);
-    }else if( p->op==TK_NULL ){
-      res = 1;
-    }
   }
 
   return res;
@@ -4725,11 +4715,12 @@ static int exprCompareVariable(Parse *pParse, Expr *pVar, Expr *pExpr){
 ** just might result in some slightly slower code.  But returning
 ** an incorrect 0 or 1 could lead to a malfunction.
 **
-** Argument pParse should normally be NULL. If it is not NULL and 
+** If pParse is not NULL then TK_VARIABLE terms in pA with bindings in
-** expression pA contains SQL variable references, then the values
+** pParse->pReprepare can be matched against literals in pB.  The 
-** currently bound to those variable references may be compared to
+** pParse->pVdbe->expmask bitmask is updated for each variable referenced.
-** simple SQL values in pB. See comments above function exprCompareVariable()
+** If pParse is NULL (the normal case) then any TK_VARIABLE term in 
-** for details.
+** Argument pParse should normally be NULL. If it is not NULL and pA or
+** pB causes a return value of 2.
 */
 int sqlite3ExprCompare(Parse *pParse, Expr *pA, Expr *pB, int iTab){
   u32 combinedFlags;
@@ -4833,6 +4824,11 @@ int sqlite3ExprCompareSkip(Expr *pA, Expr *pB, int iTab){
 ** When comparing TK_COLUMN nodes between pE1 and pE2, if pE2 has
 ** Expr.iTable<0 then assume a table number given by iTab.
 **
+** If pParse is not NULL, then the values of bound variables in pE1 are 
+** compared against literal values in pE2 and pParse->pVdbe->expmask is
+** modified to record which bound variables are referenced.  If pParse 
+** is NULL, then false will be returned if pE1 contains any bound variables.
+**
 ** When in doubt, return false.  Returning true might give a performance
 ** improvement.  Returning false might cause a performance reduction, but
 ** it will always give the correct answer and is hence always safe.