summaryrefslogtreecommitdiff
path: root/lib/racc/logfilegenerator.rb
blob: 68593c41f6eb5fbbc88c978dd02eb3cc2c4de918 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
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
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
#
# $Id: 5e9d0a01b5d56fd9cdc3d5cb078b1a3e1bbaf779 $
#
# Copyright (c) 1999-2006 Minero Aoki
#
# This program is free software.
# You can distribute/modify this program under the terms of
# the GNU LGPL, Lesser General Public License version 2.1.
# For details of the GNU LGPL, see the file "COPYING".
#

module Racc

  class LogFileGenerator

    def initialize(states, debug_flags = DebugFlags.new)
      @states = states
      @grammar = states.grammar
      @debug_flags = debug_flags
    end

    def output(out)
      output_conflict out; out.puts
      output_useless  out; out.puts
      output_rule     out; out.puts
      output_token    out; out.puts
      output_state    out
    end

    #
    # Warnings
    #

    def output_conflict(out)
      @states.each do |state|
        if state.srconf
          out.printf "state %d contains %d shift/reduce conflicts\n",
                     state.stateid, state.srconf.size
        end
        if state.rrconf
          out.printf "state %d contains %d reduce/reduce conflicts\n",
                     state.stateid, state.rrconf.size
        end
      end
    end

    def output_useless(out)
      @grammar.each do |rl|
        if rl.useless?
          out.printf "rule %d (%s) never reduced\n",
                     rl.ident, rl.target.to_s
        end
      end
      @grammar.each_nonterminal do |t|
        if t.useless?
          out.printf "useless nonterminal %s\n", t.to_s
        end
      end
    end

    #
    # States
    #

    def output_state(out)
      out << "--------- State ---------\n"

      showall = @debug_flags.la || @debug_flags.state
      @states.each do |state|
        out << "\nstate #{state.ident}\n\n"

        (showall ? state.closure : state.core).each do |ptr|
          pointer_out(out, ptr) if ptr.rule.ident != 0 or showall
        end
        out << "\n"

        action_out out, state
      end
    end

    def pointer_out(out, ptr)
      buf = sprintf("%4d) %s :", ptr.rule.ident, ptr.rule.target.to_s)
      ptr.rule.symbols.each_with_index do |tok, idx|
        buf << ' _' if idx == ptr.index
        buf << ' ' << tok.to_s
      end
      buf << ' _' if ptr.reduce?
      out.puts buf
    end

    def action_out(f, state)
      sr = state.srconf && state.srconf.dup
      rr = state.rrconf && state.rrconf.dup
      acts = state.action
      keys = acts.keys
      keys.sort! {|a,b| a.ident <=> b.ident }

      [ Shift, Reduce, Error, Accept ].each do |klass|
        keys.delete_if do |tok|
          act = acts[tok]
          if act.kind_of?(klass)
            outact f, tok, act
            if sr and c = sr.delete(tok)
              outsrconf f, c
            end
            if rr and c = rr.delete(tok)
              outrrconf f, c
            end

            true
          else
            false
          end
        end
      end
      sr.each {|tok, c| outsrconf f, c } if sr
      rr.each {|tok, c| outrrconf f, c } if rr

      act = state.defact
      if not act.kind_of?(Error) or @debug_flags.any?
        outact f, '$default', act
      end

      f.puts
      state.goto_table.each do |t, st|
        if t.nonterminal?
          f.printf "  %-12s  go to state %d\n", t.to_s, st.ident
        end
      end
    end

    def outact(f, t, act)
      case act
      when Shift
        f.printf "  %-12s  shift, and go to state %d\n",
                 t.to_s, act.goto_id
      when Reduce
        f.printf "  %-12s  reduce using rule %d (%s)\n",
                 t.to_s, act.ruleid, act.rule.target.to_s
      when Accept
        f.printf "  %-12s  accept\n", t.to_s
      when Error
        f.printf "  %-12s  error\n", t.to_s
      else
        raise "racc: fatal: wrong act for outact: act=#{act}(#{act.class})"
      end
    end

    def outsrconf(f, confs)
      confs.each do |c|
        r = c.reduce
        f.printf "  %-12s  [reduce using rule %d (%s)]\n",
                 c.shift.to_s, r.ident, r.target.to_s
      end
    end

    def outrrconf(f, confs)
      confs.each do |c|
        r = c.low_prec
        f.printf "  %-12s  [reduce using rule %d (%s)]\n",
                 c.token.to_s, r.ident, r.target.to_s
      end
    end

    #
    # Rules
    #

    def output_rule(out)
      out.print "-------- Grammar --------\n\n"
      @grammar.each do |rl|
        if @debug_flags.any? or rl.ident != 0
          out.printf "rule %d %s: %s\n",
                     rl.ident, rl.target.to_s, rl.symbols.join(' ')
        end
      end
    end

    #
    # Tokens
    #

    def output_token(out)
      out.print "------- Symbols -------\n\n"

      out.print "**Nonterminals, with rules where they appear\n\n"
      @grammar.each_nonterminal do |t|
        tmp = <<SRC
  %s (%d)
    on right: %s
    on left : %s
SRC
        out.printf tmp, t.to_s, t.ident,
                   symbol_locations(t.locate).join(' '),
                   symbol_locations(t.heads).join(' ')
      end

      out.print "\n**Terminals, with rules where they appear\n\n"
      @grammar.each_terminal do |t|
        out.printf "  %s (%d) %s\n",
                   t.to_s, t.ident, symbol_locations(t.locate).join(' ')
      end
    end

    def symbol_locations(locs)
      locs.map {|loc| loc.rule.ident }.reject {|n| n == 0 }.uniq
    end

  end

end   # module Racc