Slightly smaller and faster version of the previous check-in.

FossilOrigin-Name: f6e6fd02f4ad49c390a2d3c9626d57f9b2fff1f67eb361b30074cc1f5121810e

1 files changed, 17 insertions, 15 deletions

diff --git a/src/expr.c b/src/expr.c
index de729ea62..a2df740af 100644
--- a/src/expr.c
+++ b/src/expr.c
@@ -6137,20 +6137,12 @@ void sqlite3ExprIfFalse(Parse *pParse, Expr *pExpr, int dest, int jumpIfNull){
       break;
     }
     case TK_IS:
-    case TK_ISNOT: {
+    case TK_ISNOT:
       testcase( pExpr->op==TK_IS );
       testcase( pExpr->op==TK_ISNOT );
-      if( sqlite3ExprIsVector(pExpr->pLeft) ) goto default_expr;
       op = (pExpr->op==TK_IS) ? TK_NE : TK_EQ;
-      r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree1);
-      r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, &regFree2);
-      codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
-                  r1, r2, dest, SQLITE_NULLEQ,
-                  ExprHasProperty(pExpr,EP_Commuted));
-      testcase(op==OP_Eq); VdbeCoverageIf(v,op==OP_Eq);
-      testcase(op==OP_Ne); VdbeCoverageIf(v,op==OP_Ne);
-      break;
-    }
+      jumpIfNull = SQLITE_NULLEQ;
+      /* no break */ deliberate_fall_through
     case TK_LT:
     case TK_LE:
     case TK_GT:
@@ -6159,16 +6151,26 @@ void sqlite3ExprIfFalse(Parse *pParse, Expr *pExpr, int dest, int jumpIfNull){
     case TK_EQ: {
       int addrIsNull;
       if( sqlite3ExprIsVector(pExpr->pLeft) ) goto default_expr;
-      addrIsNull = exprComputeOperands(pParse, pExpr,
-                                 &r1, &r2, &regFree1, &regFree2);
+      if( ExprHasProperty(pExpr, EP_Subquery) && jumpIfNull!=SQLITE_NULLEQ ){
+        addrIsNull = exprComputeOperands(pParse, pExpr,
+                                   &r1, &r2, &regFree1, &regFree2);
+      }else{
+        r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree1);
+        r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, &regFree2);
+        addrIsNull = 0;
+      }
       codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
                   r1, r2, dest, jumpIfNull,ExprHasProperty(pExpr,EP_Commuted));
       assert(TK_LT==OP_Lt); testcase(op==OP_Lt); VdbeCoverageIf(v,op==OP_Lt);
       assert(TK_LE==OP_Le); testcase(op==OP_Le); VdbeCoverageIf(v,op==OP_Le);
       assert(TK_GT==OP_Gt); testcase(op==OP_Gt); VdbeCoverageIf(v,op==OP_Gt);
       assert(TK_GE==OP_Ge); testcase(op==OP_Ge); VdbeCoverageIf(v,op==OP_Ge);
-      assert(TK_EQ==OP_Eq); testcase(op==OP_Eq); VdbeCoverageIf(v,op==OP_Eq);
-      assert(TK_NE==OP_Ne); testcase(op==OP_Ne); VdbeCoverageIf(v,op==OP_Ne);
+      assert(TK_EQ==OP_Eq); testcase(op==OP_Eq);
+      VdbeCoverageIf(v, op==OP_Eq && jumpIfNull==SQLITE_NULLEQ);
+      VdbeCoverageIf(v, op==OP_Eq && jumpIfNull!=SQLITE_NULLEQ);
+      assert(TK_NE==OP_Ne); testcase(op==OP_Ne);
+      VdbeCoverageIf(v, op==OP_Ne && jumpIfNull==SQLITE_NULLEQ);
+      VdbeCoverageIf(v, op==OP_Ne && jumpIfNull!=SQLITE_NULLEQ);
       testcase( regFree1==0 );
       testcase( regFree2==0 );
       if( addrIsNull ){