-C Improve\sthe\sbytecode\sgenerated\sfor\scomparisons\sso\sthat\sif\sone\soperand\sis\na\ssubquery\sand\sthe\sother\soperand\sevaluates\sto\sNULL,\sthe\ssubquery\soperand\nis\snot\seven\scomputed.\s\sThis\sfixes\s5\sof\sthe\s12\sslow\squeries\sdescribed\nin\s[forum:/forumpost/52651713ac|forum\spost\s52651713ac].
-D 2025-06-28T17:59:15.236
+C Factor\sout\sthe\scode\sthat\stries\sto\savoid\sevaluating\ssubquery\soperands\sif\sthe\nother\soperand\sis\sNULL\sinto\sa\ssubroutine,\sso\sthat\sit\scan\sbe\smore\seasily\sreused\nby\sother\sparts\sof\sthe\scode\sgenerator.
+D 2025-06-30T10:30:47.908
F .fossil-settings/binary-glob 61195414528fb3ea9693577e1980230d78a1f8b0a54c78cf1b9b24d0a409ed6a x
F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
F src/dbpage.c b3e218f8ed74fcbb7fa805df8ca669a3718d397617b3d8a8aac3307dc315c4d6
F src/dbstat.c 73362c0df0f40ad5523a6f5501224959d0976757b511299bf892313e79d14f5c
F src/delete.c 03a77ba20e54f0f42ebd8eddf15411ed6bdb06a2c472ac4b6b336521bf7cea42
-F src/expr.c b46621069e36a2fbc966215691e4775134e2cc6c7a6e9e54b01cbb70b51d57a5
+F src/expr.c f007ab177a9900d10893a58bf6b756e89144df635bab61b25f37a17390f12778
F src/fault.c 460f3e55994363812d9d60844b2a6de88826e007
F src/fkey.c 928ed2517e8732113d2b9821aa37af639688d752f4ea9ac6e0e393d713eeb76f
F src/func.c de47a8295503aa130baae5e6d9868ecf4f7c4dbffa65d83ad1f70bdbac0ee2d6
F tool/warnings-clang.sh bbf6a1e685e534c92ec2bfba5b1745f34fb6f0bc2a362850723a9ee87c1b31a7
F tool/warnings.sh 1ad0169b022b280bcaaf94a7fa231591be96b514230ab5c98fbf15cd7df842dd
F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f
-P 5508b56fd24016c13981ec280ecdd833007c9d8dd595edb295b984c2b487b5c8
-R c5ec83310afc6f17c7231575eaf1e606
-T *branch * optimize-null-values
-T *sym-optimize-null-values *
-T -sym-trunk *
+P f147bc04776ac0056412f69dfc518016c0d5b4e9d964664e3d88f595fb29dbe0
+R 2a36b21b6d3bc1bf7db15e8f66e788a3
U drh
-Z 4eeee81d77d56831be900c22e39d8eec
+Z 4ecc3e0b30247a36c4e1fea0e6dc5b85
# Remove this line to create a well-formed Fossil manifest.
testcase( xJump==0 );
}
+/*
+** Compute the two operands of a binary operator.
+**
+** If either operand contains a subquery, then the code strives to
+** compute the operand containing the subquery second. If the other
+** operand evalutes to NULL, then a jump is made. The address of the
+** IsNull operand that does this jump is returned. The caller can use
+** this to optimize the computation so as to avoid doing the potentially
+** expensive subquery.
+**
+** If no optimization opportunities exist, return 0.
+*/
+static int exprComputeOperands(
+ Parse *pParse, /* Parsing context */
+ Expr *pExpr, /* The comparison expression */
+ int *pR1, /* OUT: Register holding the left operand */
+ int *pR2, /* OUT: Register holding the right operand */
+ int *pFree1, /* OUT: Temp register to free if not zero */
+ int *pFree2 /* OUT: Another temp register to free if not zero */
+){
+ int addrIsNull;
+ int r1, r2;
+ Vdbe *v = pParse->pVdbe;
+
+ assert( v!=0 );
+ /*
+ ** If the left operand contains a (possibly expensive) subquery and the
+ ** right operand does not and the right operation might be NULL,
+ ** then compute the right operand first and do an IsNull jump if the
+ ** right operand evalutes to NULL.
+ */
+ if( ExprHasProperty(pExpr->pLeft, EP_Subquery)
+ && !ExprHasProperty(pExpr->pRight, EP_Subquery)
+ && sqlite3ExprCanBeNull(pExpr->pRight)
+ ){
+ r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, pFree2);
+ addrIsNull = sqlite3VdbeAddOp1(v, OP_IsNull, r2); VdbeCoverage(v);
+ }else{
+ addrIsNull = 0;
+ }
+ r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, pFree1);
+ if( addrIsNull==0 ){
+ /*
+ ** If the right operand contains a subquery and the left operand does not
+ ** and the left operand might be NULL, then check the left operand do
+ ** an IsNull check on the left operand before computing the right
+ ** operand.
+ */
+ if( ExprHasProperty(pExpr->pRight, EP_Subquery)
+ && sqlite3ExprCanBeNull(pExpr->pLeft)
+ ){
+ addrIsNull = sqlite3VdbeAddOp1(v, OP_IsNull, r1); VdbeCoverage(v);
+ }
+ r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, pFree2);
+ }
+ *pR1 = r1;
+ *pR2 = r2;
+ return addrIsNull;
+}
+
+
/*
** Generate code for a boolean expression such that a jump is made
** to the label "dest" if the expression is true but execution
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;
- jumpIfNull = SQLITE_NULLEQ;
- /* no break */ deliberate_fall_through
+ r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1);
+ r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, ®Free2);
+ 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;
+ }
case TK_LT:
case TK_LE:
case TK_GT:
case TK_GE:
case TK_NE:
case TK_EQ: {
- int r2Done = 0;
- int addrBypass = 0;
+ int addrIsNull;
if( sqlite3ExprIsVector(pExpr->pLeft) ) goto default_expr;
- testcase( jumpIfNull==0 );
- /*
- ** If the left operand is a (possibly expensive) subquery and the
- ** right operand is not and the right operation might be NULL and
- ** the operator is not IS or IS NOT, then compute the right operand
- ** first and skip the computation of the left operand if the right
- ** operand is NULL.
- */
- if( jumpIfNull!=SQLITE_NULLEQ
- && ExprHasProperty(pExpr->pLeft, EP_Subquery)
- && !ExprHasProperty(pExpr->pRight, EP_Subquery)
- && sqlite3ExprCanBeNull(pExpr->pRight)
- ){
- r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, ®Free2);
- addrBypass = sqlite3VdbeAddOp2(v, OP_IsNull, r2, dest);
- VdbeCoverageIf(v, jumpIfNull==SQLITE_JUMPIFNULL);
- VdbeCoverageIf(v, jumpIfNull!=SQLITE_JUMPIFNULL);
- if( jumpIfNull==SQLITE_JUMPIFNULL ) addrBypass = 0;
- r2Done = 1;
- }
- r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1);
- if( !r2Done ){
- /*
- ** If the right operand is a subquery and the left operand is not
- ** and the left operand might be NULL and the comparison operator
- ** is not IS or IS NOT, then check the left operand to see if it is
- ** NULL and skip the computation of the right operand if it is.
- */
- if( jumpIfNull!=SQLITE_NULLEQ
- && ExprHasProperty(pExpr->pRight, EP_Subquery)
- && sqlite3ExprCanBeNull(pExpr->pLeft)
- ){
- addrBypass = sqlite3VdbeAddOp2(v, OP_IsNull, r1, dest);
- VdbeCoverageIf(v, jumpIfNull==SQLITE_JUMPIFNULL);
- VdbeCoverageIf(v, jumpIfNull!=SQLITE_JUMPIFNULL);
- if( jumpIfNull==SQLITE_JUMPIFNULL ) addrBypass = 0;
- }
- r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, ®Free2);
- }
+ addrIsNull = exprComputeOperands(pParse, pExpr,
+ &r1, &r2, ®Free1, ®Free2);
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 && 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);
+ 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);
testcase( regFree1==0 );
testcase( regFree2==0 );
- if( addrBypass ) sqlite3VdbeJumpHere(v, addrBypass);
+ if( addrIsNull ){
+ if( jumpIfNull ){
+ sqlite3VdbeChangeP2(v, addrIsNull, dest);
+ }else{
+ sqlite3VdbeJumpHere(v, addrIsNull);
+ }
+ }
break;
}
case TK_ISNULL: