Small performance optimization in the codeEqualityTerm() routine of the

code generator.

FossilOrigin-Name: 8080c6eafd1280ea870a6ab1ba715ac5af67387e69771be6cbd46dda77c3eaa8

1 files changed, 143 insertions, 116 deletions

diff --git a/src/wherecode.c b/src/wherecode.c
index 80fbbfac4..098af7375 100644
--- a/src/wherecode.c
+++ b/src/wherecode.c
@@ -604,6 +604,147 @@ static Expr *removeUnindexableInClauseTerms(
 }
 
 
+#ifndef SQLITE_OMIT_SUBQUERY
+/*
+** Generate code for a single X IN (....) term of the WHERE clause.
+**
+** This is a special-case of codeEqualityTerm() that works for IN operators
+** only.  It is broken out into a subroutine because this case is
+** uncommon and by splitting it off into a subroutine, the common case
+** runs faster.
+**
+** The current value for the constraint is left in  register iTarget.
+** This routine sets up a loop that will iterate over all values of X.
+*/
+static SQLITE_NOINLINE void codeINTerm(
+  Parse *pParse,      /* The parsing context */
+  WhereTerm *pTerm,   /* The term of the WHERE clause to be coded */
+  WhereLevel *pLevel, /* The level of the FROM clause we are working on */
+  int iEq,            /* Index of the equality term within this level */
+  int bRev,           /* True for reverse-order IN operations */
+  int iTarget         /* Attempt to leave results in this register */
+){
+  Expr *pX = pTerm->pExpr;
+  int eType = IN_INDEX_NOOP;
+  int iTab;
+  struct InLoop *pIn;
+  WhereLoop *pLoop = pLevel->pWLoop;
+  Vdbe *v = pParse->pVdbe;
+  int i;
+  int nEq = 0;
+  int *aiMap = 0;
+
+  if( (pLoop->wsFlags & WHERE_VIRTUALTABLE)==0
+    && pLoop->u.btree.pIndex!=0
+    && pLoop->u.btree.pIndex->aSortOrder[iEq]
+  ){
+    testcase( iEq==0 );
+    testcase( bRev );
+    bRev = !bRev;
+  }
+  assert( pX->op==TK_IN );
+
+  for(i=0; i<iEq; i++){
+    if( pLoop->aLTerm[i] && pLoop->aLTerm[i]->pExpr==pX ){
+      disableTerm(pLevel, pTerm);
+      return;
+    }
+  }
+  for(i=iEq;i<pLoop->nLTerm; i++){
+    assert( pLoop->aLTerm[i]!=0 );
+    if( pLoop->aLTerm[i]->pExpr==pX ) nEq++;
+  }
+
+  iTab = 0;
+  if( !ExprUseXSelect(pX) || pX->x.pSelect->pEList->nExpr==1 ){
+    eType = sqlite3FindInIndex(pParse, pX, IN_INDEX_LOOP, 0, 0, &iTab);
+  }else{
+    Expr *pExpr = pTerm->pExpr;
+    if( pExpr->iTable==0 || !ExprHasProperty(pExpr, EP_Subrtn) ){
+      sqlite3 *db = pParse->db;
+      pX = removeUnindexableInClauseTerms(pParse, iEq, pLoop, pX);
+      if( !db->mallocFailed ){
+        aiMap = (int*)sqlite3DbMallocZero(pParse->db, sizeof(int)*nEq);
+        eType = sqlite3FindInIndex(pParse, pX, IN_INDEX_LOOP, 0, aiMap,&iTab);
+        pExpr->iTable = iTab;
+      }
+      sqlite3ExprDelete(db, pX);
+    }else{
+      int n = sqlite3ExprVectorSize(pX->pLeft);
+      aiMap = (int*)sqlite3DbMallocZero(pParse->db, sizeof(int)*MAX(nEq,n));
+      eType = sqlite3FindInIndex(pParse, pX, IN_INDEX_LOOP, 0, aiMap, &iTab);
+    }
+    pX = pExpr;
+  }
+
+  if( eType==IN_INDEX_INDEX_DESC ){
+    testcase( bRev );
+    bRev = !bRev;
+  }
+  sqlite3VdbeAddOp2(v, bRev ? OP_Last : OP_Rewind, iTab, 0);
+  VdbeCoverageIf(v, bRev);
+  VdbeCoverageIf(v, !bRev);
+
+  assert( (pLoop->wsFlags & WHERE_MULTI_OR)==0 );
+  pLoop->wsFlags |= WHERE_IN_ABLE;
+  if( pLevel->u.in.nIn==0 ){
+    pLevel->addrNxt = sqlite3VdbeMakeLabel(pParse);
+  }
+  if( iEq>0 && (pLoop->wsFlags & WHERE_IN_SEEKSCAN)==0 ){
+    pLoop->wsFlags |= WHERE_IN_EARLYOUT;
+  }
+
+  i = pLevel->u.in.nIn;
+  pLevel->u.in.nIn += nEq;
+  pLevel->u.in.aInLoop =
+     sqlite3WhereRealloc(pTerm->pWC->pWInfo,
+                         pLevel->u.in.aInLoop,
+                         sizeof(pLevel->u.in.aInLoop[0])*pLevel->u.in.nIn);
+  pIn = pLevel->u.in.aInLoop;
+  if( pIn ){
+    int iMap = 0;               /* Index in aiMap[] */
+    pIn += i;
+    for(i=iEq;i<pLoop->nLTerm; i++){
+      if( pLoop->aLTerm[i]->pExpr==pX ){
+        int iOut = iTarget + i - iEq;
+        if( eType==IN_INDEX_ROWID ){
+          pIn->addrInTop = sqlite3VdbeAddOp2(v, OP_Rowid, iTab, iOut);
+        }else{
+          int iCol = aiMap ? aiMap[iMap++] : 0;
+          pIn->addrInTop = sqlite3VdbeAddOp3(v,OP_Column,iTab, iCol, iOut);
+        }
+        sqlite3VdbeAddOp1(v, OP_IsNull, iOut); VdbeCoverage(v);
+        if( i==iEq ){
+          pIn->iCur = iTab;
+          pIn->eEndLoopOp = bRev ? OP_Prev : OP_Next;
+          if( iEq>0 ){
+            pIn->iBase = iTarget - i;
+            pIn->nPrefix = i;
+          }else{
+            pIn->nPrefix = 0;
+          }
+        }else{
+          pIn->eEndLoopOp = OP_Noop;
+        }
+        pIn++;
+      }
+    }
+    testcase( iEq>0
+              && (pLoop->wsFlags & WHERE_IN_SEEKSCAN)==0
+              && (pLoop->wsFlags & WHERE_VIRTUALTABLE)!=0 );
+    if( iEq>0
+     && (pLoop->wsFlags & (WHERE_IN_SEEKSCAN|WHERE_VIRTUALTABLE))==0
+    ){
+      sqlite3VdbeAddOp3(v, OP_SeekHit, pLevel->iIdxCur, 0, iEq);
+    }
+  }else{
+    pLevel->u.in.nIn = 0;
+  }
+  sqlite3DbFree(pParse->db, aiMap);
+}
+#endif
+
+
 /*
 ** Generate code for a single equality term of the WHERE clause.  An equality
 ** term can be either X=expr or X IN (...).   pTerm is the term to be
@@ -628,7 +769,6 @@ static int codeEqualityTerm(
   int iTarget         /* Attempt to leave results in this register */
 ){
   Expr *pX = pTerm->pExpr;
-  Vdbe *v = pParse->pVdbe;
   int iReg;                  /* Register holding results */
 
   assert( pLevel->pWLoop->aLTerm[iEq]==pTerm );
@@ -637,125 +777,12 @@ static int codeEqualityTerm(
     iReg = sqlite3ExprCodeTarget(pParse, pX->pRight, iTarget);
   }else if( pX->op==TK_ISNULL ){
     iReg = iTarget;
-    sqlite3VdbeAddOp2(v, OP_Null, 0, iReg);
+    sqlite3VdbeAddOp2(pParse->pVdbe, OP_Null, 0, iReg);
 #ifndef SQLITE_OMIT_SUBQUERY
   }else{
-    int eType = IN_INDEX_NOOP;
-    int iTab;
-    struct InLoop *pIn;
-    WhereLoop *pLoop = pLevel->pWLoop;
-    int i;
-    int nEq = 0;
-    int *aiMap = 0;
-
-    if( (pLoop->wsFlags & WHERE_VIRTUALTABLE)==0
-      && pLoop->u.btree.pIndex!=0
-      && pLoop->u.btree.pIndex->aSortOrder[iEq]
-    ){
-      testcase( iEq==0 );
-      testcase( bRev );
-      bRev = !bRev;
-    }
     assert( pX->op==TK_IN );
     iReg = iTarget;
-
-    for(i=0; i<iEq; i++){
-      if( pLoop->aLTerm[i] && pLoop->aLTerm[i]->pExpr==pX ){
-        disableTerm(pLevel, pTerm);
-        return iTarget;
-      }
-    }
-    for(i=iEq;i<pLoop->nLTerm; i++){
-      assert( pLoop->aLTerm[i]!=0 );
-      if( pLoop->aLTerm[i]->pExpr==pX ) nEq++;
-    }
-
-    iTab = 0;
-    if( !ExprUseXSelect(pX) || pX->x.pSelect->pEList->nExpr==1 ){
-      eType = sqlite3FindInIndex(pParse, pX, IN_INDEX_LOOP, 0, 0, &iTab);
-    }else{
-      Expr *pExpr = pTerm->pExpr;
-      if( pExpr->iTable==0 || !ExprHasProperty(pExpr, EP_Subrtn) ){
-        sqlite3 *db = pParse->db;
-        pX = removeUnindexableInClauseTerms(pParse, iEq, pLoop, pX);
-        if( !db->mallocFailed ){
-          aiMap = (int*)sqlite3DbMallocZero(pParse->db, sizeof(int)*nEq);
-          eType = sqlite3FindInIndex(pParse, pX, IN_INDEX_LOOP, 0, aiMap,&iTab);
-          pExpr->iTable = iTab;
-        }
-        sqlite3ExprDelete(db, pX);
-      }else{
-        int n = sqlite3ExprVectorSize(pX->pLeft);
-        aiMap = (int*)sqlite3DbMallocZero(pParse->db, sizeof(int)*MAX(nEq,n));
-        eType = sqlite3FindInIndex(pParse, pX, IN_INDEX_LOOP, 0, aiMap, &iTab);
-      }
-      pX = pExpr;
-    }
-
-    if( eType==IN_INDEX_INDEX_DESC ){
-      testcase( bRev );
-      bRev = !bRev;
-    }
-    sqlite3VdbeAddOp2(v, bRev ? OP_Last : OP_Rewind, iTab, 0);
-    VdbeCoverageIf(v, bRev);
-    VdbeCoverageIf(v, !bRev);
-
-    assert( (pLoop->wsFlags & WHERE_MULTI_OR)==0 );
-    pLoop->wsFlags |= WHERE_IN_ABLE;
-    if( pLevel->u.in.nIn==0 ){
-      pLevel->addrNxt = sqlite3VdbeMakeLabel(pParse);
-    }
-    if( iEq>0 && (pLoop->wsFlags & WHERE_IN_SEEKSCAN)==0 ){
-      pLoop->wsFlags |= WHERE_IN_EARLYOUT;
-    }
-
-    i = pLevel->u.in.nIn;
-    pLevel->u.in.nIn += nEq;
-    pLevel->u.in.aInLoop =
-       sqlite3WhereRealloc(pTerm->pWC->pWInfo,
-                           pLevel->u.in.aInLoop,
-                           sizeof(pLevel->u.in.aInLoop[0])*pLevel->u.in.nIn);
-    pIn = pLevel->u.in.aInLoop;
-    if( pIn ){
-      int iMap = 0;               /* Index in aiMap[] */
-      pIn += i;
-      for(i=iEq;i<pLoop->nLTerm; i++){
-        if( pLoop->aLTerm[i]->pExpr==pX ){
-          int iOut = iReg + i - iEq;
-          if( eType==IN_INDEX_ROWID ){
-            pIn->addrInTop = sqlite3VdbeAddOp2(v, OP_Rowid, iTab, iOut);
-          }else{
-            int iCol = aiMap ? aiMap[iMap++] : 0;
-            pIn->addrInTop = sqlite3VdbeAddOp3(v,OP_Column,iTab, iCol, iOut);
-          }
-          sqlite3VdbeAddOp1(v, OP_IsNull, iOut); VdbeCoverage(v);
-          if( i==iEq ){
-            pIn->iCur = iTab;
-            pIn->eEndLoopOp = bRev ? OP_Prev : OP_Next;
-            if( iEq>0 ){
-              pIn->iBase = iReg - i;
-              pIn->nPrefix = i;
-            }else{
-              pIn->nPrefix = 0;
-            }
-          }else{
-            pIn->eEndLoopOp = OP_Noop;
-          }
-          pIn++;
-        }
-      }
-      testcase( iEq>0
-                && (pLoop->wsFlags & WHERE_IN_SEEKSCAN)==0
-                && (pLoop->wsFlags & WHERE_VIRTUALTABLE)!=0 );
-      if( iEq>0
-       && (pLoop->wsFlags & (WHERE_IN_SEEKSCAN|WHERE_VIRTUALTABLE))==0
-      ){
-        sqlite3VdbeAddOp3(v, OP_SeekHit, pLevel->iIdxCur, 0, iEq);
-      }
-    }else{
-      pLevel->u.in.nIn = 0;
-    }
-    sqlite3DbFree(pParse->db, aiMap);
+    codeINTerm(pParse, pTerm, pLevel, iEq, bRev, iTarget);
 #endif
   }