gcc/tristate.cc

   1 /* "True" vs "False" vs "Unknown".
   2    Copyright (C) 2019-2020 Free Software Foundation, Inc.
   3    Contributed by David Malcolm <dmalcolm@redhat.com>.
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify it
   8 under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 3, or (at your option)
  10 any later version.
  11
  12 GCC is distributed in the hope that it will be useful, but
  13 WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15 General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING3.  If not see
  19 <http://www.gnu.org/licenses/>.  */
  20
  21 #include "config.h"
  22 #include "system.h"
  23 #include "coretypes.h"
  24 #include "tristate.h"
  25 #include "selftest.h"
  26
  27 const char *
  28 tristate::as_string () const
  29 {
  30   switch (m_value)
  31     {
  32     default:
  33       gcc_unreachable ();
  34     case TS_UNKNOWN:
  35       return "UNKNOWN";
  36     case TS_TRUE:
  37       return "TRUE";
  38     case TS_FALSE:
  39       return "FALSE";
  40     }
  41 }
  42
  43 tristate
  44 tristate::not_ () const
  45 {
  46   switch (m_value)
  47     {
  48     default:
  49       gcc_unreachable ();
  50     case TS_UNKNOWN:
  51       return tristate (TS_UNKNOWN);
  52     case TS_TRUE:
  53       return tristate (TS_FALSE);
  54     case TS_FALSE:
  55       return tristate (TS_TRUE);
  56     }
  57 }
  58
  59 tristate
  60 tristate::or_ (tristate other) const
  61 {
  62   switch (m_value)
  63     {
  64     default:
  65       gcc_unreachable ();
  66     case TS_UNKNOWN:
  67       if (other.is_true ())
  68         return tristate (TS_TRUE);
  69       else
  70         return tristate (TS_UNKNOWN);
  71     case TS_FALSE:
  72       return other;
  73     case TS_TRUE:
  74       return tristate (TS_TRUE);
  75     }
  76 }
  77
  78 tristate
  79 tristate::and_ (tristate other) const
  80 {
  81   switch (m_value)
  82     {
  83     default:
  84       gcc_unreachable ();
  85     case TS_UNKNOWN:
  86       if (other.is_false ())
  87         return tristate (TS_FALSE);
  88       else
  89         return tristate (TS_UNKNOWN);
  90     case TS_TRUE:
  91       return other;
  92     case TS_FALSE:
  93       return tristate (TS_FALSE);
  94     }
  95 }
  96
  97 #if CHECKING_P
  98
  99 namespace selftest {
 100
 101 #define ASSERT_TRISTATE_TRUE(TRISTATE) \
 102   SELFTEST_BEGIN_STMT                                   \
 103   ASSERT_EQ (TRISTATE, tristate (tristate::TS_TRUE));   \
 104   SELFTEST_END_STMT
 105
 106 #define ASSERT_TRISTATE_FALSE(TRISTATE) \
 107   SELFTEST_BEGIN_STMT                                   \
 108   ASSERT_EQ (TRISTATE, tristate (tristate::TS_FALSE));  \
 109   SELFTEST_END_STMT
 110
 111 #define ASSERT_TRISTATE_UNKNOWN(TRISTATE) \
 112   SELFTEST_BEGIN_STMT                                           \
 113   ASSERT_EQ (TRISTATE, tristate (tristate::TS_UNKNOWN));        \
 114   SELFTEST_END_STMT
 115
 116 /* Test tristate's ctors, along with is_*, as_string, operator==, and
 117    operator!=.  */
 118
 119 static void
 120 test_ctors ()
 121 {
 122   tristate u (tristate::TS_UNKNOWN);
 123   ASSERT_FALSE (u.is_known ());
 124   ASSERT_FALSE (u.is_true ());
 125   ASSERT_FALSE (u.is_false ());
 126   ASSERT_STREQ (u.as_string (), "UNKNOWN");
 127
 128   tristate t (tristate::TS_TRUE);
 129   ASSERT_TRUE (t.is_known ());
 130   ASSERT_TRUE (t.is_true ());
 131   ASSERT_FALSE (t.is_false ());
 132   ASSERT_STREQ (t.as_string (), "TRUE");
 133
 134   tristate f (tristate::TS_FALSE);
 135   ASSERT_TRUE (f.is_known ());
 136   ASSERT_FALSE (f.is_true ());
 137   ASSERT_TRUE (f.is_false ());
 138   ASSERT_STREQ (f.as_string (), "FALSE");
 139
 140   ASSERT_EQ (u, u);
 141   ASSERT_EQ (t, t);
 142   ASSERT_EQ (f, f);
 143   ASSERT_NE (u, t);
 144   ASSERT_NE (u, f);
 145   ASSERT_NE (t, f);
 146
 147   tristate t2 (true);
 148   ASSERT_TRUE (t2.is_true ());
 149   ASSERT_EQ (t, t2);
 150
 151   tristate f2 (false);
 152   ASSERT_TRUE (f2.is_false ());
 153   ASSERT_EQ (f, f2);
 154
 155   tristate u2 (tristate::unknown ());
 156   ASSERT_TRUE (!u2.is_known ());
 157   ASSERT_EQ (u, u2);
 158 }
 159
 160 /* Test && on tristate instances.  */
 161
 162 static void
 163 test_and ()
 164 {
 165   ASSERT_TRISTATE_UNKNOWN (tristate::unknown () && tristate::unknown ());
 166
 167   ASSERT_TRISTATE_FALSE (tristate (false) && tristate (false));
 168   ASSERT_TRISTATE_FALSE (tristate (false) && tristate (true));
 169   ASSERT_TRISTATE_FALSE (tristate (true) && tristate (false));
 170   ASSERT_TRISTATE_TRUE (tristate (true) && tristate (true));
 171
 172   ASSERT_TRISTATE_UNKNOWN (tristate::unknown () && tristate (true));
 173   ASSERT_TRISTATE_UNKNOWN (tristate (true) && tristate::unknown ());
 174
 175   ASSERT_TRISTATE_FALSE (tristate::unknown () && tristate (false));
 176   ASSERT_TRISTATE_FALSE (tristate (false) && tristate::unknown ());
 177 }
 178
 179 /* Test || on tristate instances.  */
 180
 181 static void
 182 test_or ()
 183 {
 184   ASSERT_TRISTATE_UNKNOWN (tristate::unknown () || tristate::unknown ());
 185
 186   ASSERT_TRISTATE_FALSE (tristate (false) || tristate (false));
 187   ASSERT_TRISTATE_TRUE (tristate (false) || tristate (true));
 188   ASSERT_TRISTATE_TRUE (tristate (true) || tristate (false));
 189   ASSERT_TRISTATE_TRUE (tristate (true) || tristate (true));
 190
 191   ASSERT_TRISTATE_TRUE (tristate::unknown () || tristate (true));
 192   ASSERT_TRISTATE_TRUE (tristate (true) || tristate::unknown ());
 193
 194   ASSERT_TRISTATE_UNKNOWN (tristate::unknown () || tristate (false));
 195   ASSERT_TRISTATE_UNKNOWN (tristate (false) || tristate::unknown ());
 196 }
 197
 198 /* Test ! on tristate instances.  */
 199
 200 static void
 201 test_not ()
 202 {
 203   ASSERT_TRISTATE_UNKNOWN (!tristate::unknown ());
 204   ASSERT_TRISTATE_FALSE (!tristate (true));
 205   ASSERT_TRISTATE_TRUE (!tristate (false));
 206 }
 207
 208 /* Run all of the selftests within this file.  */
 209
 210 void
 211 tristate_cc_tests ()
 212 {
 213   test_ctors ();
 214   test_and ();
 215   test_or ();
 216   test_not ();
 217 }
 218
 219 } // namespace selftest
 220
 221 #endif /* CHECKING_P */