/ Check-in [83622f3f]
Login

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

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.
Downloads: Tarball | ZIP archive | SQL archive
Timelines: family | ancestors | descendants | both | trunk
Files: files | file ages | folders
SHA1:83622f3f50030e4d6abafb99d99742928aaf157c
User & Date: drh 2016-08-10 13:30:43
Context
2016-08-10
13:34
Increment the version number to 3.15. check-in: 8c2701e7 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: 83622f3f user: drh tags: trunk
11:50
Fix pcache1TruncateUnsafe() run faster for the case where iLimit is very close to iMaxKey. check-in: b07a26df user: drh tags: trunk
Changes
Hide Diffs Unified Diffs Ignore Whitespace Patch

Changes to tool/lemon.c.

4227
4228
4229
4230
4231
4232
4233
4234
4235
4236

4237
4238
4239
4240
4241

4242
4243
4244
4245
4246
4247
4248
4249
4250
4251
4252
4253
4254
    }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++;







<


>
|
|
|

|
>





|







4227
4228
4229
4230
4231
4232
4233

4234
4235
4236
4237
4238
4239
4240
4241
4242
4243
4244
4245
4246
4247
4248
4249
4250
4251
4252
4253
4254
4255
    }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.

112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130

131
132


133
134
135




136
137
138
139
140
141
142
143
144
**                                      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:
**







|








|

|
>

<
>
>
|
<
<
>
>
>
>

|







112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132

133
134
135


136
137
138
139
140
141
142
143
144
145
146
147
148
**                                      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:
**