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Overview
Comment:Improved comments on the lempar.c parser template. Adjust the YY_SHIFT_USE_DFLT constant in the Lemon-generated parser tables so as to guarantee that it is always out of range of the yy_lookahead[] table.
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SHA1: 83622f3f50030e4d6abafb99d99742928aaf157c
User & Date: drh 2016-08-10 13:30:43.279
Context
2016-08-10
13:34
Increment the version number to 3.15. (check-in: 8c2701e70a user: drh tags: trunk)
13:30
Improved comments on the lempar.c parser template. Adjust the YY_SHIFT_USE_DFLT constant in the Lemon-generated parser tables so as to guarantee that it is always out of range of the yy_lookahead[] table. (check-in: 83622f3f50 user: drh tags: trunk)
11:50
Fix pcache1TruncateUnsafe() run faster for the case where iLimit is very close to iMaxKey. (check-in: b07a26df06 user: drh tags: trunk)
Changes
Unified Diff Ignore Whitespace Patch
Changes to tool/lemon.c.
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    }else{
      j++;
    }
  }
  fprintf(out, "};\n"); lineno++;

  /* Output the yy_shift_ofst[] table */
  fprintf(out, "#define YY_SHIFT_USE_DFLT (%d)\n", mnTknOfst-1); lineno++;
  n = lemp->nxstate;
  while( n>0 && lemp->sorted[n-1]->iTknOfst==NO_OFFSET ) n--;

  fprintf(out, "#define YY_SHIFT_COUNT (%d)\n", n-1); lineno++;
  fprintf(out, "#define YY_SHIFT_MIN   (%d)\n", mnTknOfst); lineno++;
  fprintf(out, "#define YY_SHIFT_MAX   (%d)\n", mxTknOfst); lineno++;
  fprintf(out, "static const %s yy_shift_ofst[] = {\n", 
          minimum_size_type(mnTknOfst-1, mxTknOfst, &sz)); lineno++;

  lemp->tablesize += n*sz;
  for(i=j=0; i<n; i++){
    int ofst;
    stp = lemp->sorted[i];
    ofst = stp->iTknOfst;
    if( ofst==NO_OFFSET ) ofst = mnTknOfst - 1;
    if( j==0 ) fprintf(out," /* %5d */ ", i);
    fprintf(out, " %4d,", ofst);
    if( j==9 || i==n-1 ){
      fprintf(out, "\n"); lineno++;
      j = 0;
    }else{
      j++;








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    }else{
      j++;
    }
  }
  fprintf(out, "};\n"); lineno++;

  /* Output the yy_shift_ofst[] table */

  n = lemp->nxstate;
  while( n>0 && lemp->sorted[n-1]->iTknOfst==NO_OFFSET ) n--;
  fprintf(out, "#define YY_SHIFT_USE_DFLT (%d)\n", lemp->nactiontab); lineno++;
  fprintf(out, "#define YY_SHIFT_COUNT    (%d)\n", n-1); lineno++;
  fprintf(out, "#define YY_SHIFT_MIN      (%d)\n", mnTknOfst); lineno++;
  fprintf(out, "#define YY_SHIFT_MAX      (%d)\n", mxTknOfst); lineno++;
  fprintf(out, "static const %s yy_shift_ofst[] = {\n", 
       minimum_size_type(mnTknOfst, lemp->nterminal+lemp->nactiontab, &sz));
       lineno++;
  lemp->tablesize += n*sz;
  for(i=j=0; i<n; i++){
    int ofst;
    stp = lemp->sorted[i];
    ofst = stp->iTknOfst;
    if( ofst==NO_OFFSET ) ofst = lemp->nactiontab;
    if( j==0 ) fprintf(out," /* %5d */ ", i);
    fprintf(out, " %4d,", ofst);
    if( j==9 || i==n-1 ){
      fprintf(out, "\n"); lineno++;
      j = 0;
    }else{
      j++;
︙︙
Changes to tool/lempar.c.
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**                                      token onto the stack and goto state N.
**
**   N between YY_MIN_SHIFTREDUCE       Shift to an arbitrary state then
**     and YY_MAX_SHIFTREDUCE           reduce by rule N-YY_MIN_SHIFTREDUCE.
**
**   N between YY_MIN_REDUCE            Reduce by rule N-YY_MIN_REDUCE
**     and YY_MAX_REDUCE

**   N == YY_ERROR_ACTION               A syntax error has occurred.
**
**   N == YY_ACCEPT_ACTION              The parser accepts its input.
**
**   N == YY_NO_ACTION                  No such action.  Denotes unused
**                                      slots in the yy_action[] table.
**
** The action table is constructed as a single large table named yy_action[].
** Given state S and lookahead X, the action is computed as
**
**      yy_action[ yy_shift_ofst[S] + X ]

**

** If the index value yy_shift_ofst[S]+X is out of range or if the value
** yy_lookahead[yy_shift_ofst[S]+X] is not equal to X or if yy_shift_ofst[S]
** is equal to YY_SHIFT_USE_DFLT, it means that the action is not in the table
** and that yy_default[S] should be used instead.  



**
** The formula above is for computing the action when the lookahead is
** a terminal symbol.  If the lookahead is a non-terminal (as occurs after
** a reduce action) then the yy_reduce_ofst[] array is used in place of
** the yy_shift_ofst[] array and YY_REDUCE_USE_DFLT is used in place of
** YY_SHIFT_USE_DFLT.
**
** The following are the tables generated in this section:
**








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**                                      token onto the stack and goto state N.
**
**   N between YY_MIN_SHIFTREDUCE       Shift to an arbitrary state then
**     and YY_MAX_SHIFTREDUCE           reduce by rule N-YY_MIN_SHIFTREDUCE.
**
**   N between YY_MIN_REDUCE            Reduce by rule N-YY_MIN_REDUCE
**     and YY_MAX_REDUCE
**
**   N == YY_ERROR_ACTION               A syntax error has occurred.
**
**   N == YY_ACCEPT_ACTION              The parser accepts its input.
**
**   N == YY_NO_ACTION                  No such action.  Denotes unused
**                                      slots in the yy_action[] table.
**
** The action table is constructed as a single large table named yy_action[].
** Given state S and lookahead X, the action is computed as either:
**
**    (A)   N = yy_action[ yy_shift_ofst[S] + X ]
**    (B)   N = yy_default[S]
**
** The (A) formula is preferred.  The B formula is used instead if:
**    (1)  The yy_shift_ofst[S]+X value is out of range, or
**    (2)  yy_lookahead[yy_shift_ofst[S]+X] is not equal to X, or
**    (3)  yy_shift_ofst[S] equal YY_SHIFT_USE_DFLT.

** (Implementation note: YY_SHIFT_USE_DFLT is chosen so that
** YY_SHIFT_USE_DFLT+X will be out of range for all possible lookaheads X.
** Hence only tests (1) and (2) need to be evaluated.)
**
** The formulas above are for computing the action when the lookahead is
** a terminal symbol.  If the lookahead is a non-terminal (as occurs after
** a reduce action) then the yy_reduce_ofst[] array is used in place of
** the yy_shift_ofst[] array and YY_REDUCE_USE_DFLT is used in place of
** YY_SHIFT_USE_DFLT.
**
** The following are the tables generated in this section:
**
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