Factor out the code that handles AND and OR short-circuiting into a

separate subroutine, for performance and legibility.

FossilOrigin-Name: cab84a65c3825c59f3a7a750f4983563ce7ad007125cbcf35c187326289fea89
This commit is contained in:
drh
2025-09-24 13:10:55 +00:00
parent 9300c4a13c
commit ca574fa1d5
3 changed files with 73 additions and 52 deletions

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@@ -1,5 +1,5 @@
C Improved\sshort-circuit\sevaluation\sof\sAND\sand\sOR.\s\sAll\sappears\sto\swork,\sbut\nthere\sare\sstill\stesting\sand\sperformance\sissues\sto\sbe\sworked\sout.
D 2025-09-24T00:13:28.522
C Factor\sout\sthe\scode\sthat\shandles\sAND\sand\sOR\sshort-circuiting\sinto\sa\nseparate\ssubroutine,\sfor\sperformance\sand\slegibility.
D 2025-09-24T13:10:55.288
F .fossil-settings/binary-glob 61195414528fb3ea9693577e1980230d78a1f8b0a54c78cf1b9b24d0a409ed6a x
F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
@@ -693,7 +693,7 @@ F src/date.c b6f92001f4b1f73f21774927488661d28f4dac9cd9701ed96486d96b44f5b058
F src/dbpage.c 081c59d84f187aa0eb48d98faf9578a00bde360f68438d646a86b618653d2479
F src/dbstat.c 73362c0df0f40ad5523a6f5501224959d0976757b511299bf892313e79d14f5c
F src/delete.c 03a77ba20e54f0f42ebd8eddf15411ed6bdb06a2c472ac4b6b336521bf7cea42
F src/expr.c 4a7954d065441c552a4b6c79703c67096d872a58263804f906f15e111ee122ac
F src/expr.c 941ab6b635a7c6c30572c0223065e03ba6fbf656aa886f5b821ccf962ce95bc0
F src/fault.c 460f3e55994363812d9d60844b2a6de88826e007
F src/fkey.c 928ed2517e8732113d2b9821aa37af639688d752f4ea9ac6e0e393d713eeb76f
F src/func.c de47a8295503aa130baae5e6d9868ecf4f7c4dbffa65d83ad1f70bdbac0ee2d6
@@ -2175,11 +2175,8 @@ F tool/version-info.c 3b36468a90faf1bbd59c65fd0eb66522d9f941eedd364fabccd7227350
F tool/warnings-clang.sh bbf6a1e685e534c92ec2bfba5b1745f34fb6f0bc2a362850723a9ee87c1b31a7
F tool/warnings.sh 1ad0169b022b280bcaaf94a7fa231591be96b514230ab5c98fbf15cd7df842dd
F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f
P cea8bf79e18d55a8658e48a967cd0b7970b6f88badb769cfbb1f66ab24fb9ec8
R bd21c11f0c7e1866fc947e8383f45ff5
T *branch * short-circuit
T *sym-short-circuit *
T -sym-trunk *
P 0d4447aa61848deecf9170afce031f7b353b91d58474f3f094ce34e46be7f99e
R 1772208b5f6079b8843463f58173d5e0
U drh
Z e14eb04d760631ac91058b9280e3cbea
Z 0a260950732cda975b0bb04f700f181c
# Remove this line to create a well-formed Fossil manifest.

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@@ -1 +1 @@
0d4447aa61848deecf9170afce031f7b353b91d58474f3f094ce34e46be7f99e
cab84a65c3825c59f3a7a750f4983563ce7ad007125cbcf35c187326289fea89

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@@ -4810,6 +4810,71 @@ static int exprPartidxExprLookup(Parse *pParse, Expr *pExpr, int iTarget){
return 0;
}
/*
** This is the code to implement sqlite3ExprCodeTarget() for the
** case of an AND or OR operator. It is factored out for performance
** and legibility.
*/
static SQLITE_NOINLINE int exprCodeTargetAndOr(
Parse *pParse, /* Parsing context */
Expr *pExpr, /* AND or OR expression to be coded */
int target, /* Put result in this register, guaranteed */
int *pTmpReg /* Number of a temporary register */
){
int op; /* The opcode. TK_AND or TK_OR */
int skipOp; /* Opcode for the branch that skips one operand */
int addrSkip; /* Branch instruction that skips one of the operands */
int regSS = 0;
int r1, r2; /* Registers holding left and right operands */
Expr *pAlt; /* Alternative, simplified expression */
Vdbe *v; /* statement being coded */
assert( pExpr!=0 );
op = pExpr->op;
assert( op==TK_AND || op==TK_OR );
assert( TK_AND==OP_And ); testcase( op==TK_AND );
assert( TK_OR==OP_Or ); testcase( op==TK_OR );
pAlt = sqlite3ExprSimplifiedAndOr(pExpr);
if( pAlt!=pExpr ){
return sqlite3ExprCodeTarget(pParse, pAlt, target);
}
assert( pParse->pVdbe!=0 );
v = pParse->pVdbe;
skipOp = op==TK_AND ? OP_IfNot : OP_If;
if( exprEvalRhsFirst(pExpr) ){
r2 = regSS = sqlite3ExprCodeTarget(pParse, pExpr->pRight, target);
addrSkip = sqlite3VdbeAddOp1(v, skipOp, r2);
VdbeComment((v, "skip left operand"));
VdbeCoverage(v);
}else{
r2 = 0;
addrSkip = 0;
}
r1 = regSS = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target);
if( addrSkip==0 ){
if( ExprHasProperty(pExpr->pRight, EP_Subquery) ){
addrSkip = sqlite3VdbeAddOp1(v, skipOp, r1);
VdbeComment((v, "skip right operand"));
VdbeCoverage(v);
}
r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, pTmpReg);
}
sqlite3VdbeAddOp3(v, op, r2, r1, target);
testcase( (*pTmpReg)==0 );
if( addrSkip==0 ){
/* no-op */
}else if( regSS==target ){
sqlite3VdbeJumpHere(v, addrSkip);
}else{
sqlite3VdbeAddOp2(v, OP_Goto, 0, sqlite3VdbeCurrentAddr(v)+2);
sqlite3VdbeJumpHere(v, addrSkip);
sqlite3VdbeAddOp3(v, OP_Move, regSS, target, 1);
VdbeComment((v, "short-circut value"));
}
return target;
}
/*
** Generate code into the current Vdbe to evaluate the given
@@ -5103,48 +5168,7 @@ expr_code_doover:
}
case TK_AND:
case TK_OR: {
int addrSkip, skipOp, regSS = 0;
Expr *pAlt;
assert( TK_AND==OP_And ); testcase( op==TK_AND );
assert( TK_OR==OP_Or ); testcase( op==TK_OR );
pAlt = sqlite3ExprSimplifiedAndOr(pExpr);
if( pAlt!=pExpr ){
pExpr = pAlt;
goto expr_code_doover;
}
skipOp = op==TK_AND ? OP_IfNot : OP_If;
if( exprEvalRhsFirst(pExpr) ){
r2 = regSS = sqlite3ExprCodeTarget(pParse, pExpr->pRight, target);
addrSkip = sqlite3VdbeAddOp1( v, skipOp, r2);
VdbeComment((v, "skip left operand"));
VdbeCoverage(v);
}else{
r2 = 0;
addrSkip = 0;
}
r1 = regSS = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target);
if( addrSkip==0 ){
if( ExprHasProperty(pExpr->pRight, EP_Subquery) ){
addrSkip = sqlite3VdbeAddOp1(v, skipOp, r1);
VdbeComment((v, "skip right operand"));
VdbeCoverage(v);
}
r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, &regFree1);
}
sqlite3VdbeAddOp3(v, op, r2, r1, target);
testcase( regFree1==0 );
testcase( regFree2==0 );
if( addrSkip==0 ){
/* no-op */
}else if( regSS==target ){
sqlite3VdbeJumpHere(v, addrSkip);
}else{
sqlite3VdbeAddOp2(v, OP_Goto, 0, sqlite3VdbeCurrentAddr(v)+2);
sqlite3VdbeJumpHere(v, addrSkip);
sqlite3VdbeAddOp2(v, OP_Null, 0, target);
VdbeComment((v, "short-circut value"));
}
inReg = exprCodeTargetAndOr(pParse, pExpr, target, &regFree1);
break;
}
case TK_PLUS: