Optimizations to exprAnalyze() and sqlite3WhereExprUsage() save about 1.5

million CPU cycles for speedtest1, and result in a smaller binary.

FossilOrigin-Name: 1f2252e65dc5847c82246fab87dcad035bf594ba7c45362de87a009b7ebcf2d6

diff --git a/manifest b/manifest
index fd242e54e1cfbe3781f4afc64e1817933eb18958..65ea3a6c49abd45010d3776129a7c62d01ecd74c 100644 (file)
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Move\sthe\sTK_IS\stoken\sso\sthat\sit\sis\sadjacent\sto\sthe\sTK_IN\stoken,\sas\sthis\nallows\sthe\sC\scompiler\sto\soptimize\sbetter,\sresulting\sin\sa\sslightly\ssmaller\nand\sfaster\sexecutable.
-D 2021-12-02T14:28:36.785
+C Optimizations\sto\sexprAnalyze()\sand\ssqlite3WhereExprUsage()\ssave\sabout\s1.5\nmillion\sCPU\scycles\sfor\sspeedtest1,\sand\sresult\sin\sa\ssmaller\sbinary.
+D 2021-12-02T18:15:16.866
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -640,7 +640,7 @@ F src/walker.c f890a3298418d7cba3b69b8803594fdc484ea241206a8dfa99db6dd36f8cbb3b
 F src/where.c b50391df607937593596fbb8ea39f673d9a3715a65750567b442d22dd20720ca
 F src/whereInt.h 1630d9418512b080598e9a72b8af6b8bd1b9ab13fee1458f151762b6df206791
 F src/wherecode.c 1f5b62f46d284c8886945eb7438415bc27e23e87bb60b9ee468fa6bd31268f33
-F src/whereexpr.c da93d2227cc5246fe4a79d130f2a1a215017e12d76a035434145c443abd6f64b
+F src/whereexpr.c ac082ec617802e7fc9c190aa0819696a7144a8aa0cad91948323b83720e5105c
 F src/window.c 5d3b397b0c026d0ff5890244ac41359e524c01ae31e78782e1ff418c3e271a9e
 F test/8_3_names.test ebbb5cd36741350040fd28b432ceadf495be25b2
 F test/affinity2.test ce1aafc86e110685b324e9a763eab4f2a73f737842ec3b687bd965867de90627
@@ -1933,7 +1933,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P fcc509d325dabe06275e7804183bb8b4ba6470a45b443bc8292eecd0974e6367
-R 888c8c19b41c8406ec3840142d61350f
+P 8832fa9088414a8d285a457a4effad0b7d610a87ca73cfb5c5812e784649761e
+R 7228b3364cf2efa906def2eee014e4fe
 U drh
-Z 0b6dacbe87596435aee017d0aa63fe31
+Z 0ddb7e6cff00de145e1d39d556b5aab6

diff --git a/manifest.uuid b/manifest.uuid
index 1a7fe9bc70f0423f017e980afe26976a14b7ef45..a9c01fe47e1981dec04d7609124cdbbb35e42137 100644 (file)
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-8832fa9088414a8d285a457a4effad0b7d610a87ca73cfb5c5812e784649761e
\ No newline at end of file
+1f2252e65dc5847c82246fab87dcad035bf594ba7c45362de87a009b7ebcf2d6
\ No newline at end of file

diff --git a/src/whereexpr.c b/src/whereexpr.c
index bb013f1c6ff78f11aafc84f9d701a7c942e802a3..542114e91dbf0a8b4faafc8d0ac185839ccbeef7 100644 (file)
--- a/src/whereexpr.c
+++ b/src/whereexpr.c
@@ -1076,6 +1076,7 @@ static void exprAnalyze(
   pExpr = pTerm->pExpr;
   assert( pExpr!=0 ); /* Because malloc() has not failed */
   assert( pExpr->op!=TK_AS && pExpr->op!=TK_COLLATE );
+  pMaskSet->bVarSelect = 0;
   prereqLeft = sqlite3WhereExprUsage(pMaskSet, pExpr->pLeft);
   op = pExpr->op;
   if( op==TK_IN ){
@@ -1086,12 +1087,25 @@ static void exprAnalyze(
     }else{
       pTerm->prereqRight = sqlite3WhereExprListUsage(pMaskSet, pExpr->x.pList);
     }
+    prereqAll = prereqLeft | pTerm->prereqRight;
   }else{
     pTerm->prereqRight = sqlite3WhereExprUsage(pMaskSet, pExpr->pRight);
+    if( pExpr->pLeft==0 || ExprUseXSelect(pExpr) || pExpr->x.pList!=0 ){
+      prereqAll = sqlite3WhereExprUsageNN(pMaskSet, pExpr);
+    }else{
+      prereqAll = prereqLeft | pTerm->prereqRight;
+    }
   }
-  pMaskSet->bVarSelect = 0;
-  prereqAll = sqlite3WhereExprUsageNN(pMaskSet, pExpr);
   if( pMaskSet->bVarSelect ) pTerm->wtFlags |= TERM_VARSELECT;
+
+#ifdef SQLITE_DEBUG
+  if( prereqAll!=sqlite3WhereExprUsageNN(pMaskSet, pExpr) ){
+    printf("\n*** Incorrect prereqAll computed for:\n");
+    sqlite3TreeViewExpr(0,pExpr,0);
+    abort();
+  }
+#endif
+
   if( ExprHasProperty(pExpr, EP_FromJoin) ){
     Bitmask x = sqlite3WhereGetMask(pMaskSet, pExpr->iRightJoinTable);
     prereqAll |= x;
@@ -1556,15 +1570,38 @@ void sqlite3WhereClauseClear(WhereClause *pWC){
 ** These routines walk (recursively) an expression tree and generate
 ** a bitmask indicating which tables are used in that expression
 ** tree.
+**
+** sqlite3WhereExprUsage(MaskSet, Expr) ->
+**
+**       Return a Bitmask of all tables referenced by Expr.  Expr can be
+**       be NULL, in which case 0 is returned.
+**
+** sqlite3WhereExprUsageNN(MaskSet, Expr) ->
+**
+**       Same as sqlite3WhereExprUsage() except that Expr must not be
+**       NULL.  The "NN" suffix on the name stands for "Not Null".
+**
+** sqlite3WhereExprListUsage(MaskSet, ExprList) ->
+**
+**       Return a Bitmask of all tables referenced by every expression
+**       in the expression list ExprList.  ExprList can be NULL, in which
+**       case 0 is returned.
+**
+** sqlite3WhereExprUsageFull(MaskSet, ExprList) ->
+**
+**       Internal use only.  Called only by sqlite3WhereExprUsageNN() for
+**       complex expressions that require pushing register values onto
+**       the stack.  Many calls to sqlite3WhereExprUsageNN() do not need
+**       the more complex analysis done by this routine.  Hence, the
+**       computations done by this routine are broken out into a separate
+**       "no-inline" function to avoid the stack push overhead in the
+**       common case where it is not needed.
 */
-Bitmask sqlite3WhereExprUsageNN(WhereMaskSet *pMaskSet, Expr *p){
+static SQLITE_NOINLINE Bitmask sqlite3WhereExprUsageFull(
+  WhereMaskSet *pMaskSet,
+  Expr *p
+){
   Bitmask mask;
-  if( p->op==TK_COLUMN && !ExprHasProperty(p, EP_FixedCol) ){
-    return sqlite3WhereGetMask(pMaskSet, p->iTable);
-  }else if( ExprHasProperty(p, EP_TokenOnly|EP_Leaf) ){
-    assert( p->op!=TK_IF_NULL_ROW );
-    return 0;
-  }
   mask = (p->op==TK_IF_NULL_ROW) ? sqlite3WhereGetMask(pMaskSet, p->iTable) : 0;
   if( p->pLeft ) mask |= sqlite3WhereExprUsageNN(pMaskSet, p->pLeft);
   if( p->pRight ){
@@ -1586,6 +1623,15 @@ Bitmask sqlite3WhereExprUsageNN(WhereMaskSet *pMaskSet, Expr *p){
 #endif
   return mask;
 }
+Bitmask sqlite3WhereExprUsageNN(WhereMaskSet *pMaskSet, Expr *p){
+  if( p->op==TK_COLUMN && !ExprHasProperty(p, EP_FixedCol) ){
+    return sqlite3WhereGetMask(pMaskSet, p->iTable);
+  }else if( ExprHasProperty(p, EP_TokenOnly|EP_Leaf) ){
+    assert( p->op!=TK_IF_NULL_ROW );
+    return 0;
+  }
+  return sqlite3WhereExprUsageFull(pMaskSet, p);
+}
 Bitmask sqlite3WhereExprUsage(WhereMaskSet *pMaskSet, Expr *p){
   return p ? sqlite3WhereExprUsageNN(pMaskSet,p) : 0;
 }