4 files changed, 47 insertions, 18 deletions

diff --git a/src/where.c b/src/where.c
index f08c350b0..4820a5c03 100644
--- a/src/where.c
+++ b/src/where.c
@@ -253,6 +253,30 @@ Bitmask sqlite3WhereGetMask(WhereMaskSet *pMaskSet, int iCursor){
   return 0;
 }
 
+/* Allocate memory that is automatically freed when pWInfo is freed.
+*/
+void *sqlite3WhereMalloc(WhereInfo *pWInfo, u64 nByte){
+  WhereMemBlock *pBlock;
+  pBlock = sqlite3DbMallocRawNN(pWInfo->pParse->db, nByte+sizeof(*pBlock));
+  if( pBlock ){
+    pBlock->pNext = pWInfo->pMemToFree;
+    pBlock->sz = nByte;
+    pWInfo->pMemToFree = pBlock;
+    pBlock++;
+  }
+  return (void*)pBlock;
+}
+void *sqlite3WhereRealloc(WhereInfo *pWInfo, void *pOld, u64 nByte){
+  void *pNew = sqlite3WhereMalloc(pWInfo, nByte);
+  if( pNew && pOld ){
+    WhereMemBlock *pOldBlk = (WhereMemBlock*)pOld;
+    pOldBlk--;
+    assert( pOldBlk->sz<nByte );
+    memcpy(pNew, pOld, pOldBlk->sz);
+  }
+  return pNew;
+}
+
 /*
 ** Create a new mask for cursor iCursor.
 **
@@ -2216,15 +2240,7 @@ static void whereLoopDelete(sqlite3 *db, WhereLoop *p){
 ** Free a WhereInfo structure
 */
 static void whereInfoFree(sqlite3 *db, WhereInfo *pWInfo){
-  int i;
   assert( pWInfo!=0 );
-  for(i=0; i<pWInfo->nLevel; i++){
-    WhereLevel *pLevel = &pWInfo->a[i];
-    if( pLevel->pWLoop && (pLevel->pWLoop->wsFlags & WHERE_IN_ABLE)!=0 ){
-      assert( (pLevel->pWLoop->wsFlags & WHERE_MULTI_OR)==0 );
-      sqlite3DbFree(db, pLevel->u.in.aInLoop);
-    }
-  }
   sqlite3WhereClauseClear(&pWInfo->sWC);
   while( pWInfo->pLoops ){
     WhereLoop *p = pWInfo->pLoops;
@@ -2232,6 +2248,11 @@ static void whereInfoFree(sqlite3 *db, WhereInfo *pWInfo){
     whereLoopDelete(db, p);
   }
   assert( pWInfo->pExprMods==0 );
+  while( pWInfo->pMemToFree ){
+    WhereMemBlock *pNext = pWInfo->pMemToFree->pNext;
+    sqlite3DbFreeNN(db, pWInfo->pMemToFree);
+    pWInfo->pMemToFree = pNext;
+  }
   sqlite3DbFreeNN(db, pWInfo);
 }
 
diff --git a/src/whereInt.h b/src/whereInt.h
index 3fc39f6b4..e0f44d6ba 100644
--- a/src/whereInt.h
+++ b/src/whereInt.h
@@ -32,6 +32,16 @@ typedef struct WhereLoopBuilder WhereLoopBuilder;
 typedef struct WhereScan WhereScan;
 typedef struct WhereOrCost WhereOrCost;
 typedef struct WhereOrSet WhereOrSet;
+typedef struct WhereMemBlock WhereMemBlock;
+
+/*
+** This object is a header on a block of allocated memory that will be
+** automatically freed when its WInfo oject is destructed.
+*/
+struct WhereMemBlock {
+  WhereMemBlock *pNext;      /* Next block in the chain */
+  u8 sz;                     /* Bytes of space */
+};
 
 /*
 ** This object contains information needed to implement a single nested
@@ -478,6 +488,7 @@ struct WhereInfo {
   int iEndWhere;            /* End of the WHERE clause itself */
   WhereLoop *pLoops;        /* List of all WhereLoop objects */
   WhereExprMod *pExprMods;  /* Expression modifications */
+  WhereMemBlock *pMemToFree;/* Memory to free when this object destroyed */
   Bitmask revMask;          /* Mask of ORDER BY terms that need reversing */
   WhereClause sWC;          /* Decomposition of the WHERE clause */
   WhereMaskSet sMaskSet;    /* Map cursor numbers to bitmasks */
@@ -503,6 +514,8 @@ WhereTerm *sqlite3WhereFindTerm(
   u32 op,               /* Mask of WO_xx values describing operator */
   Index *pIdx           /* Must be compatible with this index, if not NULL */
 );
+void *sqlite3WhereMalloc(WhereInfo *pWInfo, u64 nByte);
+void *sqlite3WhereRealloc(WhereInfo *pWInfo, void *pOld, u64 nByte);
 
 /* wherecode.c: */
 #ifndef SQLITE_OMIT_EXPLAIN
diff --git a/src/wherecode.c b/src/wherecode.c
index bab514a69..561b34fc8 100644
--- a/src/wherecode.c
+++ b/src/wherecode.c
@@ -640,8 +640,9 @@ static int codeEqualityTerm(
     i = pLevel->u.in.nIn;
     pLevel->u.in.nIn += nEq;
     pLevel->u.in.aInLoop =
-       sqlite3DbReallocOrFree(pParse->db, pLevel->u.in.aInLoop,
-                              sizeof(pLevel->u.in.aInLoop[0])*pLevel->u.in.nIn);
+       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[] */
diff --git a/src/whereexpr.c b/src/whereexpr.c
index 26a521fff..a3316db65 100644
--- a/src/whereexpr.c
+++ b/src/whereexpr.c
@@ -64,7 +64,7 @@ static int whereClauseInsert(WhereClause *pWC, Expr *p, u16 wtFlags){
   if( pWC->nTerm>=pWC->nSlot ){
     WhereTerm *pOld = pWC->a;
     sqlite3 *db = pWC->pWInfo->pParse->db;
-    pWC->a = sqlite3DbMallocRawNN(db, sizeof(pWC->a[0])*pWC->nSlot*2 );
+    pWC->a = sqlite3WhereMalloc(pWC->pWInfo, sizeof(pWC->a[0])*pWC->nSlot*2 );
     if( pWC->a==0 ){
       if( wtFlags & TERM_DYNAMIC ){
         sqlite3ExprDelete(db, p);
@@ -73,10 +73,7 @@ static int whereClauseInsert(WhereClause *pWC, Expr *p, u16 wtFlags){
       return 0;
     }
     memcpy(pWC->a, pOld, sizeof(pWC->a[0])*pWC->nTerm);
-    if( pOld!=pWC->aStatic ){
-      sqlite3DbFree(db, pOld);
-    }
-    pWC->nSlot = sqlite3DbMallocSize(db, pWC->a)/sizeof(pWC->a[0]);
+    pWC->nSlot = pWC->nSlot*2;
   }
   pTerm = &pWC->a[idx = pWC->nTerm++];
   if( (wtFlags & TERM_VIRTUAL)==0 ) pWC->nBase = pWC->nTerm;
@@ -1686,9 +1683,6 @@ void sqlite3WhereClauseClear(WhereClause *pWC){
       a++;
     }
   }
-  if( pWC->a!=pWC->aStatic ){
-    sqlite3DbFree(db, pWC->a);
-  }
 }