mirror of
https://git.savannah.gnu.org/git/bison.git
synced 2026-03-09 04:13:03 +00:00
cff03fb2b9
When reporting useless rules and nonterminals, say "useless in grammar" instead of "useless", and say "useless in parser" instead of "never reduced". Discussed starting at <http://lists.gnu.org/archive/html/bison-patches/2007-10/msg00033.html>. * NEWS (2.3a+): Mention this change. * data/xslt/xml2text.xsl: Update output text and expected input XML element names to match changes below. * data/xslt/xml2xhtml.xsl: Likewise. (xsl:template match="bison-xml-report"): Add missing entry in Table of Contents: "Rules useless in parser due to conflicts". * doc/bison.texinfo (Decl Summary): Reword a little. (Understanding): Update example output for changes below. * src/gram.c: (rule_useful_p): Rename to... (rule_useful_in_grammar_p): ... this. (rule_useless_p): Rename to... (rule_useless_in_grammar_p): ... this. (rule_never_reduced_p): Rename to... (rule_useless_in_parser_p): ... this. (grammar_rules_print): Update for renames. (grammar_rules_print_xml): Update for renames. (grammar_rules_never_reduced_report): Rename to... (grammar_rules_useless_report): ... this since it is used for either kind of useless rule. * src/gram.h: Reword comments and update function names in prototypes. * src/main.c (main): Say "rule useless in parser due to conflicts". * src/print-xml.c (print_rules_never_reduced): Rename to... (print_rules_useless_in_parser): ... this, and rename output XML element "rules-never-reduced" to "rules-useless-in-parser". (print_xml): Update for rename. * src/print.c (print_results): Say "Rules useless in parser due to conflicts". * src/reduce.c (reduce_grammar_tables): Say "rule useless in grammar". (nonterminals_reduce): Say "nonterminal useless in grammar". (reduce_output): Say "Nonterminals useless in grammar". Say "Rules useless in grammar". (reduce_xml): Rename output XML element "useless" to "useless-in-grammar". (reduce_print): Don't report the count of grammatically useless rules as "rules never reduced" just because %yacc is specified. In the correct report of this count, say nonterminal(s) and rule(s) "useless in grammar". * tests/conflicts.at (S/R in initial): Update expected output. (Defaulted Conflicted Reduction): Likewise. (Unreachable States After Conflict Resolution): Likewise. * tests/existing.at (GNU pic Grammar): Likewise. * tests/reduce.at (Useless Nonterminals): Likewise. (Useless Rules): Likewise. (Reduced Automaton): Likewise. (Underivable Rules): Likewise. (Empty Language): Likewise.
354 lines
8.2 KiB
Plaintext
354 lines
8.2 KiB
Plaintext
# Exercising Bison Grammar Reduction. -*- Autotest -*-
|
|
# Copyright (C) 2001, 2002, 2007 Free Software Foundation, Inc.
|
|
|
|
# This program is free software: you can redistribute it and/or modify
|
|
# it under the terms of the GNU General Public License as published by
|
|
# the Free Software Foundation, either version 3 of the License, or
|
|
# (at your option) any later version.
|
|
#
|
|
# This program is distributed in the hope that it will be useful,
|
|
# but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
# GNU General Public License for more details.
|
|
#
|
|
# You should have received a copy of the GNU General Public License
|
|
# along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
AT_BANNER([[Grammar Reduction.]])
|
|
|
|
|
|
## ------------------- ##
|
|
## Useless Terminals. ##
|
|
## ------------------- ##
|
|
|
|
AT_SETUP([Useless Terminals])
|
|
|
|
AT_DATA([[input.y]],
|
|
[[%verbose
|
|
%output "input.c"
|
|
|
|
%token useless1
|
|
%token useless2
|
|
%token useless3
|
|
%token useless4
|
|
%token useless5
|
|
%token useless6
|
|
%token useless7
|
|
%token useless8
|
|
%token useless9
|
|
|
|
%token useful
|
|
%%
|
|
exp: useful;
|
|
]])
|
|
|
|
AT_CHECK([[bison input.y]])
|
|
|
|
AT_CHECK([[sed -n '/^Grammar/q;/^$/!p' input.output]], 0,
|
|
[[Terminals which are not used
|
|
useless1
|
|
useless2
|
|
useless3
|
|
useless4
|
|
useless5
|
|
useless6
|
|
useless7
|
|
useless8
|
|
useless9
|
|
]])
|
|
|
|
AT_CLEANUP
|
|
|
|
|
|
|
|
## ---------------------- ##
|
|
## Useless Nonterminals. ##
|
|
## ---------------------- ##
|
|
|
|
AT_SETUP([Useless Nonterminals])
|
|
|
|
AT_DATA([[input.y]],
|
|
[[%verbose
|
|
%output "input.c"
|
|
|
|
%nterm useless1
|
|
%nterm useless2
|
|
%nterm useless3
|
|
%nterm useless4
|
|
%nterm useless5
|
|
%nterm useless6
|
|
%nterm useless7
|
|
%nterm useless8
|
|
%nterm useless9
|
|
|
|
%token useful
|
|
%%
|
|
exp: useful;
|
|
]])
|
|
|
|
AT_CHECK([[bison input.y]], 0, [],
|
|
[[input.y: warning: 9 nonterminals useless in grammar
|
|
input.y:4.8-15: warning: nonterminal useless in grammar: useless1
|
|
input.y:5.8-15: warning: nonterminal useless in grammar: useless2
|
|
input.y:6.8-15: warning: nonterminal useless in grammar: useless3
|
|
input.y:7.8-15: warning: nonterminal useless in grammar: useless4
|
|
input.y:8.8-15: warning: nonterminal useless in grammar: useless5
|
|
input.y:9.8-15: warning: nonterminal useless in grammar: useless6
|
|
input.y:10.8-15: warning: nonterminal useless in grammar: useless7
|
|
input.y:11.8-15: warning: nonterminal useless in grammar: useless8
|
|
input.y:12.8-15: warning: nonterminal useless in grammar: useless9
|
|
]])
|
|
|
|
AT_CHECK([[sed -n '/^Grammar/q;/^$/!p' input.output]], 0,
|
|
[[Nonterminals useless in grammar
|
|
useless1
|
|
useless2
|
|
useless3
|
|
useless4
|
|
useless5
|
|
useless6
|
|
useless7
|
|
useless8
|
|
useless9
|
|
]])
|
|
|
|
AT_CLEANUP
|
|
|
|
|
|
|
|
## --------------- ##
|
|
## Useless Rules. ##
|
|
## --------------- ##
|
|
|
|
AT_SETUP([Useless Rules])
|
|
|
|
AT_KEYWORDS([report])
|
|
|
|
AT_DATA([[input.y]],
|
|
[[%verbose
|
|
%output "input.c"
|
|
%token useful
|
|
%%
|
|
exp: useful;
|
|
useless1: '1';
|
|
useless2: '2';
|
|
useless3: '3';
|
|
useless4: '4';
|
|
useless5: '5';
|
|
useless6: '6';
|
|
useless7: '7';
|
|
useless8: '8';
|
|
useless9: '9';
|
|
]])
|
|
|
|
AT_CHECK([[bison input.y]], 0, [],
|
|
[[input.y: warning: 9 nonterminals and 9 rules useless in grammar
|
|
input.y:6.1-8: warning: nonterminal useless in grammar: useless1
|
|
input.y:7.1-8: warning: nonterminal useless in grammar: useless2
|
|
input.y:8.1-8: warning: nonterminal useless in grammar: useless3
|
|
input.y:9.1-8: warning: nonterminal useless in grammar: useless4
|
|
input.y:10.1-8: warning: nonterminal useless in grammar: useless5
|
|
input.y:11.1-8: warning: nonterminal useless in grammar: useless6
|
|
input.y:12.1-8: warning: nonterminal useless in grammar: useless7
|
|
input.y:13.1-8: warning: nonterminal useless in grammar: useless8
|
|
input.y:14.1-8: warning: nonterminal useless in grammar: useless9
|
|
input.y:6.11-13: warning: rule useless in grammar: useless1: '1'
|
|
input.y:7.11-13: warning: rule useless in grammar: useless2: '2'
|
|
input.y:8.11-13: warning: rule useless in grammar: useless3: '3'
|
|
input.y:9.11-13: warning: rule useless in grammar: useless4: '4'
|
|
input.y:10.11-13: warning: rule useless in grammar: useless5: '5'
|
|
input.y:11.11-13: warning: rule useless in grammar: useless6: '6'
|
|
input.y:12.11-13: warning: rule useless in grammar: useless7: '7'
|
|
input.y:13.11-13: warning: rule useless in grammar: useless8: '8'
|
|
input.y:14.11-13: warning: rule useless in grammar: useless9: '9'
|
|
]])
|
|
|
|
AT_CHECK([[sed -n '/^Grammar/q;/^$/!p' input.output]], 0,
|
|
[[Nonterminals useless in grammar
|
|
useless1
|
|
useless2
|
|
useless3
|
|
useless4
|
|
useless5
|
|
useless6
|
|
useless7
|
|
useless8
|
|
useless9
|
|
Terminals which are not used
|
|
'1'
|
|
'2'
|
|
'3'
|
|
'4'
|
|
'5'
|
|
'6'
|
|
'7'
|
|
'8'
|
|
'9'
|
|
Rules useless in grammar
|
|
2 useless1: '1'
|
|
3 useless2: '2'
|
|
4 useless3: '3'
|
|
5 useless4: '4'
|
|
6 useless5: '5'
|
|
7 useless6: '6'
|
|
8 useless7: '7'
|
|
9 useless8: '8'
|
|
10 useless9: '9'
|
|
]])
|
|
|
|
AT_CLEANUP
|
|
|
|
|
|
|
|
## ------------------- ##
|
|
## Reduced Automaton. ##
|
|
## ------------------- ##
|
|
|
|
# Check that the automaton is that as the for the grammar reduced by
|
|
# hand.
|
|
|
|
AT_SETUP([Reduced Automaton])
|
|
|
|
AT_KEYWORDS([report])
|
|
|
|
# The non reduced grammar.
|
|
# ------------------------
|
|
AT_DATA([[not-reduced.y]],
|
|
[[/* A useless token. */
|
|
%token useless_token
|
|
/* A useful one. */
|
|
%token useful
|
|
%verbose
|
|
%output "not-reduced.c"
|
|
|
|
%%
|
|
|
|
exp: useful { /* A useful action. */ }
|
|
| non_productive { /* A non productive action. */ }
|
|
;
|
|
|
|
not_reachable: useful { /* A not reachable action. */ }
|
|
;
|
|
|
|
non_productive: non_productive useless_token
|
|
{ /* Another non productive action. */ }
|
|
;
|
|
%%
|
|
]])
|
|
|
|
AT_CHECK([[bison not-reduced.y]], 0, [],
|
|
[[not-reduced.y: warning: 2 nonterminals and 3 rules useless in grammar
|
|
not-reduced.y:14.1-13: warning: nonterminal useless in grammar: not_reachable
|
|
not-reduced.y:11.6-19: warning: nonterminal useless in grammar: non_productive
|
|
not-reduced.y:11.6-57: warning: rule useless in grammar: exp: non_productive
|
|
not-reduced.y:14.16-56: warning: rule useless in grammar: not_reachable: useful
|
|
not-reduced.y:17.17-18.63: warning: rule useless in grammar: non_productive: non_productive useless_token
|
|
]])
|
|
|
|
AT_CHECK([[sed -n '/^Grammar/q;/^$/!p' not-reduced.output]], 0,
|
|
[[Nonterminals useless in grammar
|
|
not_reachable
|
|
non_productive
|
|
Terminals which are not used
|
|
useless_token
|
|
Rules useless in grammar
|
|
2 exp: non_productive
|
|
3 not_reachable: useful
|
|
4 non_productive: non_productive useless_token
|
|
]])
|
|
|
|
# The reduced grammar.
|
|
# --------------------
|
|
AT_DATA([[reduced.y]],
|
|
[[/* A useless token. */
|
|
%token useless_token
|
|
/* A useful one. */
|
|
%token useful
|
|
%verbose
|
|
%output "reduced.c"
|
|
|
|
%%
|
|
|
|
exp: useful { /* A useful action. */ }
|
|
// | non_productive { /* A non productive action. */ } */
|
|
;
|
|
|
|
//not_reachable: useful { /* A not reachable action. */ }
|
|
// ;
|
|
|
|
//non_productive: non_productive useless_token
|
|
// { /* Another non productive action. */ }
|
|
// ;
|
|
%%
|
|
]])
|
|
|
|
AT_CHECK([[bison reduced.y]])
|
|
|
|
# Comparing the parsers.
|
|
cp reduced.c expout
|
|
AT_CHECK([sed 's/not-reduced/reduced/g' not-reduced.c], 0, [expout])
|
|
|
|
AT_CLEANUP
|
|
|
|
|
|
|
|
## ------------------- ##
|
|
## Underivable Rules. ##
|
|
## ------------------- ##
|
|
|
|
AT_SETUP([Underivable Rules])
|
|
|
|
AT_KEYWORDS([report])
|
|
|
|
AT_DATA([[input.y]],
|
|
[[%verbose
|
|
%output "input.c"
|
|
%token useful
|
|
%%
|
|
exp: useful | underivable;
|
|
underivable: indirection;
|
|
indirection: underivable;
|
|
]])
|
|
|
|
AT_CHECK([[bison input.y]], 0, [],
|
|
[[input.y: warning: 2 nonterminals and 3 rules useless in grammar
|
|
input.y:5.15-25: warning: nonterminal useless in grammar: underivable
|
|
input.y:6.14-24: warning: nonterminal useless in grammar: indirection
|
|
input.y:5.15-25: warning: rule useless in grammar: exp: underivable
|
|
input.y:6.14-24: warning: rule useless in grammar: underivable: indirection
|
|
input.y:7.14-24: warning: rule useless in grammar: indirection: underivable
|
|
]])
|
|
|
|
AT_CHECK([[sed -n '/^Grammar/q;/^$/!p' input.output]], 0,
|
|
[[Nonterminals useless in grammar
|
|
underivable
|
|
indirection
|
|
Rules useless in grammar
|
|
2 exp: underivable
|
|
3 underivable: indirection
|
|
4 indirection: underivable
|
|
]])
|
|
|
|
AT_CLEANUP
|
|
|
|
|
|
|
|
## ---------------- ##
|
|
## Empty Language. ##
|
|
## ---------------- ##
|
|
|
|
AT_SETUP([Empty Language])
|
|
|
|
AT_DATA([[input.y]],
|
|
[[%output "input.c"
|
|
%%
|
|
exp: exp;
|
|
]])
|
|
|
|
AT_CHECK([[bison input.y]], 1, [],
|
|
[[input.y: warning: 2 nonterminals and 2 rules useless in grammar
|
|
input.y:3.1-3: fatal error: start symbol exp does not derive any sentence
|
|
]])
|
|
|
|
AT_CLEANUP
|