Many hyperlinks are disabled.
Use anonymous login
to enable hyperlinks.
Overview
| Comment: | Further improvements to parser speed by enlarging lookup tables to eliminate the need to do range checking on the index prior to lookup. |
|---|---|
| Downloads: | Tarball | ZIP archive | SQL archive |
| Timelines: | family | ancestors | descendants | both | lemon-optimization |
| Files: | files | file ages | folders |
| SHA3-256: |
47d3e091ae49eb7947af5abef9b5b96b |
| User & Date: | drh 2019-08-28 11:31:11 |
Context
|
2019-08-28
| ||
| 11:49 | Fix an unreachable branch in sqlite3ParserFallback() Closed-Leaf check-in: e059178b user: drh tags: lemon-optimization | |
| 11:31 | Further improvements to parser speed by enlarging lookup tables to eliminate the need to do range checking on the index prior to lookup. check-in: 47d3e091 user: drh tags: lemon-optimization | |
| 02:09 | Increase the size of the yy_lookahead table so that it is never necessary to down bounds checking on the index. check-in: bafd8723 user: drh tags: lemon-optimization | |
Changes
Changes to tool/lemon.c.
4502 4503 4504 4505 4506 4507 4508 4509 4510 4511 4512 4513 4514 4515 4516 |
fprintf(out, "};\n"); lineno++;
tplt_xfer(lemp->name,in,out,&lineno);
/* Generate the table of fallback tokens.
*/
if( lemp->has_fallback ){
int mx = lemp->nterminal - 1;
while( mx>0 && lemp->symbols[mx]->fallback==0 ){ mx--; }
lemp->tablesize += (mx+1)*szCodeType;
for(i=0; i<=mx; i++){
struct symbol *p = lemp->symbols[i];
if( p->fallback==0 ){
fprintf(out, " 0, /* %10s => nothing */\n", p->name);
}else{
fprintf(out, " %3d, /* %10s => %s */\n", p->fallback->index,
|
> > | |
4502 4503 4504 4505 4506 4507 4508 4509 4510 4511 4512 4513 4514 4515 4516 4517 4518 |
fprintf(out, "};\n"); lineno++;
tplt_xfer(lemp->name,in,out,&lineno);
/* Generate the table of fallback tokens.
*/
if( lemp->has_fallback ){
int mx = lemp->nterminal - 1;
/* 2019-08-28: Generate fallback entries for every token to avoid
** having to do a range check on the index */
/* while( mx>0 && lemp->symbols[mx]->fallback==0 ){ mx--; } */
lemp->tablesize += (mx+1)*szCodeType;
for(i=0; i<=mx; i++){
struct symbol *p = lemp->symbols[i];
if( p->fallback==0 ){
fprintf(out, " 0, /* %10s => nothing */\n", p->name);
}else{
fprintf(out, " %3d, /* %10s => %s */\n", p->fallback->index,
|
Changes to tool/lempar.c.
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
...
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
|
assert( iLookAhead!=YYNOCODE );
assert( iLookAhead < YYNTOKEN );
i += iLookAhead;
assert( i<(int)YY_NLOOKAHEAD );
if( yy_lookahead[i]!=iLookAhead ){
#ifdef YYFALLBACK
YYCODETYPE iFallback; /* Fallback token */
if( iLookAhead<sizeof(yyFallback)/sizeof(yyFallback[0])
&& (iFallback = yyFallback[iLookAhead])!=0 ){
#ifndef NDEBUG
if( yyTraceFILE ){
fprintf(yyTraceFILE, "%sFALLBACK %s => %s\n",
yyTracePrompt, yyTokenName[iLookAhead], yyTokenName[iFallback]);
}
#endif
assert( yyFallback[iFallback]==0 ); /* Fallback loop must terminate */
................................................................................
iLookAhead = iFallback;
continue;
}
#endif
#ifdef YYWILDCARD
{
int j = i - iLookAhead + YYWILDCARD;
if(
#if YY_SHIFT_MIN+YYWILDCARD<0
j>=0 &&
#endif
#if YY_SHIFT_MAX+YYWILDCARD>=YY_ACTTAB_COUNT
j<YY_ACTTAB_COUNT &&
#endif
j<(int)(sizeof(yy_lookahead)/sizeof(yy_lookahead[0])) &&
yy_lookahead[j]==YYWILDCARD && iLookAhead>0
){
#ifndef NDEBUG
if( yyTraceFILE ){
fprintf(yyTraceFILE, "%sWILDCARD %s => %s\n",
yyTracePrompt, yyTokenName[iLookAhead],
yyTokenName[YYWILDCARD]);
}
#endif /* NDEBUG */
|
|
|
>
<
<
<
<
<
<
<
|
|
<
|
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
...
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
|
assert( iLookAhead!=YYNOCODE );
assert( iLookAhead < YYNTOKEN );
i += iLookAhead;
assert( i<(int)YY_NLOOKAHEAD );
if( yy_lookahead[i]!=iLookAhead ){
#ifdef YYFALLBACK
YYCODETYPE iFallback; /* Fallback token */
assert( iLookAhead<sizeof(yyFallback)/sizeof(yyFallback[0]) );
iFallback = yyFallback[iLookAhead];
if( iFallback!=0 ){
#ifndef NDEBUG
if( yyTraceFILE ){
fprintf(yyTraceFILE, "%sFALLBACK %s => %s\n",
yyTracePrompt, yyTokenName[iLookAhead], yyTokenName[iFallback]);
}
#endif
assert( yyFallback[iFallback]==0 ); /* Fallback loop must terminate */
................................................................................
iLookAhead = iFallback;
continue;
}
#endif
#ifdef YYWILDCARD
{
int j = i - iLookAhead + YYWILDCARD;
assert( j<(int)(sizeof(yy_lookahead)/sizeof(yy_lookahead[0])) );
if( yy_lookahead[j]==YYWILDCARD && iLookAhead>0 ){
#ifndef NDEBUG
if( yyTraceFILE ){
fprintf(yyTraceFILE, "%sWILDCARD %s => %s\n",
yyTracePrompt, yyTokenName[iLookAhead],
yyTokenName[YYWILDCARD]);
}
#endif /* NDEBUG */
|