SQLite

Check-in [ba6663beef]
Login

Many hyperlinks are disabled.
Use anonymous login to enable hyperlinks.

Overview
Comment:Performance optimization in the yy_find_shift_action() routine of the Lemon-generated parser.
Downloads: Tarball | ZIP archive
Timelines: family | ancestors | descendants | both | trunk
Files: files | file ages | folders
SHA1: ba6663beefcc8060e6f3be6ab37c13fdbb08b7de
User & Date: drh 2016-08-10 01:43:30.837
Context
2016-08-10
11:50
Fix pcache1TruncateUnsafe() run faster for the case where iLimit is very close to iMaxKey. (check-in: b07a26df06 user: drh tags: trunk)
01:43
Performance optimization in the yy_find_shift_action() routine of the Lemon-generated parser. (check-in: ba6663beef user: drh tags: trunk)
2016-08-09
21:01
Fix harmless compiler warning. (check-in: 9a5a4f6e3b user: drh tags: trunk)
Changes
Side-by-Side Diff Ignore Whitespace Patch
Changes to tool/lempar.c.
︙
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461



462
463
464
465
466




467
468
469
470
471




472
473
474
475
476



477
478

479
480
481

482
483
484


485
486
487
488
489
490





491
492
493
494



495
496
497
498
499
500
501
502
503

446
447
448
449
450
451
452

453
454
455

456



457
458
459
460




461
462
463
464
465




466
467
468
469
470
471



472
473
474
475

476
477
478

479
480


481
482
483





484
485
486
487
488
489



490
491
492
493

494
495
496
497
498
499
500








-



-

-
-
-
+
+
+

-
-
-
-
+
+
+
+

-
-
-
-
+
+
+
+


-
-
-
+
+
+

-
+


-
+

-
-
+
+

-
-
-
-
-
+
+
+
+
+

-
-
-
+
+
+

-








  int i;
  int stateno = pParser->yytos->stateno;
 
  if( stateno>=YY_MIN_REDUCE ) return stateno;
  assert( stateno <= YY_SHIFT_COUNT );
  do{
    i = yy_shift_ofst[stateno];
    if( i==YY_SHIFT_USE_DFLT ) return yy_default[stateno];
    assert( iLookAhead!=YYNOCODE );
    i += iLookAhead;
    if( i<0 || i>=YY_ACTTAB_COUNT || yy_lookahead[i]!=iLookAhead ){
      if( iLookAhead>0 ){
#ifdef YYFALLBACK
        YYCODETYPE iFallback;            /* Fallback token */
        if( iLookAhead<sizeof(yyFallback)/sizeof(yyFallback[0])
               && (iFallback = yyFallback[iLookAhead])!=0 ){
      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]);
          }
        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;
        }
        assert( yyFallback[iFallback]==0 ); /* Fallback loop must terminate */
        iLookAhead = iFallback;
        continue;
      }
#endif
#ifdef YYWILDCARD
        {
          int j = i - iLookAhead + YYWILDCARD;
          if( 
      {
        int j = i - iLookAhead + YYWILDCARD;
        if( 
#if YY_SHIFT_MIN+YYWILDCARD<0
            j>=0 &&
          j>=0 &&
#endif
#if YY_SHIFT_MAX+YYWILDCARD>=YY_ACTTAB_COUNT
            j<YY_ACTTAB_COUNT &&
          j<YY_ACTTAB_COUNT &&
#endif
            yy_lookahead[j]==YYWILDCARD
          ){
          yy_lookahead[j]==YYWILDCARD && iLookAhead>0
        ){
#ifndef NDEBUG
            if( yyTraceFILE ){
              fprintf(yyTraceFILE, "%sWILDCARD %s => %s\n",
                 yyTracePrompt, yyTokenName[iLookAhead],
                 yyTokenName[YYWILDCARD]);
            }
          if( yyTraceFILE ){
            fprintf(yyTraceFILE, "%sWILDCARD %s => %s\n",
               yyTracePrompt, yyTokenName[iLookAhead],
               yyTokenName[YYWILDCARD]);
          }
#endif /* NDEBUG */
            return yy_action[j];
          }
        }
          return yy_action[j];
        }
      }
#endif /* YYWILDCARD */
      }
      return yy_default[stateno];
    }else{
      return yy_action[i];
    }
  }while(1);
}
︙