Fix handling of "continue" and "break" from inside the loop for the right

operand of a RIGHT JOIN.

FossilOrigin-Name: b6e773a26c2c6ee76ea61acb059b4e676d07ea62f6db9c513638f8986557cf04

3 files changed, 16 insertions, 6 deletions

diff --git a/src/vdbe.c b/src/vdbe.c
index 18286c297..45a47756e 100644
--- a/src/vdbe.c
+++ b/src/vdbe.c
@@ -993,8 +993,12 @@ jump_to_p2:
 
 /* Opcode:  Return P1 P2 P3 * *
 **
-** Jump to the next instruction after the address in register P1.  After
-** the jump, register P1 becomes undefined.
+** Jump to the next instruction after the address stored in register P1.
+**
+** It used to be that after the jump, register P1 would become undefined.
+** However, for the subroutine used for the inner loop of a RIGHT JOIN,
+** it is useful for R1 register to be unchanged, so that is what happens
+** now.
 **
 ** P2 is not used by the byte-code engine.  However, if P2 is positive
 ** and also less than the current address, then the "EXPLAIN" output
@@ -1012,7 +1016,7 @@ case OP_Return: {           /* in1 */
   pIn1 = &aMem[pOp->p1];
   assert( pIn1->flags==MEM_Int );
   pOp = &aOp[pIn1->u.i];
-  pIn1->flags = MEM_Undefined;
+  /*  pIn1->flags = MEM_Undefined; */
   break;
 }
 
diff --git a/src/where.c b/src/where.c
index 3677759ce..defbc860f 100644
--- a/src/where.c
+++ b/src/where.c
@@ -5880,6 +5880,7 @@ WhereInfo *sqlite3WhereBegin(
       pRJ->regBloom = ++pParse->nMem;
       sqlite3VdbeAddOp2(v, OP_Blob, 65536, pRJ->regBloom);
       pRJ->regReturn = ++pParse->nMem;
+      pRJ->addrInit = sqlite3VdbeAddOp2(v, OP_Integer, 0, pRJ->regReturn);
       assert( pTab==pTabItem->pTab );
       if( HasRowid(pTab) ){
         KeyInfo *pInfo;
@@ -6013,7 +6014,11 @@ void sqlite3WhereEnd(WhereInfo *pWInfo){
       /* Terminate the subroutine that forms the interior of the loop of
       ** the RIGHT JOIN table */
       WhereRightJoin *pRJ = pLevel->pRJ;
-      sqlite3VdbeChangeP1(v, pRJ->addrSubrtn-1, sqlite3VdbeCurrentAddr(v));
+      int addrHere = sqlite3VdbeCurrentAddr(v);
+      sqlite3VdbeChangeP1(v, pRJ->addrSubrtn-1, addrHere);
+      sqlite3VdbeChangeP1(v, pRJ->addrInit, addrHere);
+      sqlite3VdbeResolveLabel(v, pLevel->addrCont);
+      pLevel->addrCont = 0;
       sqlite3VdbeAddOp2(v, OP_Return, pRJ->regReturn, pRJ->addrSubrtn);
     }
     pLoop = pLevel->pWLoop;
@@ -6043,7 +6048,7 @@ void sqlite3WhereEnd(WhereInfo *pWInfo){
       }
 #endif /* SQLITE_DISABLE_SKIPAHEAD_DISTINCT */
       /* The common case: Advance to the next row */
-      sqlite3VdbeResolveLabel(v, pLevel->addrCont);
+      if( pLevel->addrCont ) sqlite3VdbeResolveLabel(v, pLevel->addrCont);
       sqlite3VdbeAddOp3(v, pLevel->op, pLevel->p1, pLevel->p2, pLevel->p3);
       sqlite3VdbeChangeP5(v, pLevel->p5);
       VdbeCoverage(v);
@@ -6058,7 +6063,7 @@ void sqlite3WhereEnd(WhereInfo *pWInfo){
 #ifndef SQLITE_DISABLE_SKIPAHEAD_DISTINCT
       if( addrSeek ) sqlite3VdbeJumpHere(v, addrSeek);
 #endif
-    }else{
+    }else if( pLevel->addrCont ){
       sqlite3VdbeResolveLabel(v, pLevel->addrCont);
     }
     if( (pLoop->wsFlags & WHERE_IN_ABLE)!=0 && pLevel->u.in.nIn>0 ){
diff --git a/src/whereInt.h b/src/whereInt.h
index 7b5be3011..6be8234e2 100644
--- a/src/whereInt.h
+++ b/src/whereInt.h
@@ -52,6 +52,7 @@ struct WhereRightJoin {
   int regBloom;        /* Bloom filter for iRJMatch */
   int regReturn;       /* Return register for the interior subroutine */
   int addrSubrtn;      /* Starting address for the interior subroutine */
+  int addrInit;        /* OP_Integer used for early init of regReturn */
 };
 
 /*