Add new files for IELR and canonical LR implementation.

[bison.git] / src / Sbitset.h

diff --git a/src/Sbitset.h b/src/Sbitset.h
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+++ b/src/Sbitset.h
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+/* A simple, memory-efficient bitset implementation.
+
+   Copyright (C) 2009 Free Software Foundation, Inc.
+
+   This file is part of Bison, the GNU Compiler Compiler.
+
+   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/>.  */
+
+#ifndef SBITSET_H_
+# define SBITSET_H_
+
+typedef char *Sbitset;
+typedef size_t Sbitset__Index;
+
+#define Sbitset__nbytes(NBITS)            (((NBITS)+7)/8)
+#define Sbitset__byteAddress(SELF, INDEX) (((SELF) + (INDEX)/8))
+#define Sbitset__bit_mask(INDEX)          (0x1 << (7 - (INDEX)%8))
+#define Sbitset__last_byte_mask(NBITS)    (0xff << (7 - ((NBITS)-1)%8))
+
+/* nbits must not be 0.  */
+Sbitset Sbitset__new (Sbitset__Index nbits);
+Sbitset Sbitset__new_on_obstack (Sbitset__Index nbits,
+                                 struct obstack *obstackp);
+void Sbitset__delete (Sbitset self);
+
+#define Sbitset__test(SELF, INDEX)                                            \
+  ((*Sbitset__byteAddress ((SELF), (INDEX)) & Sbitset__bit_mask (INDEX)) != 0)
+
+bool Sbitset__isEmpty (Sbitset self, Sbitset__Index nbits);
+
+void Sbitset__fprint(Sbitset self, Sbitset__Index nbits, FILE *file);
+
+#define Sbitset__set(SELF, INDEX)                                             \
+do {                                                                          \
+  *Sbitset__byteAddress ((SELF), (INDEX)) =                                   \
+    *Sbitset__byteAddress ((SELF), (INDEX)) | Sbitset__bit_mask (INDEX);      \
+} while(0)
+
+#define Sbitset__reset(SELF, INDEX)                                           \
+do {                                                                          \
+  *Sbitset__byteAddress ((SELF), (INDEX)) =                                   \
+    *Sbitset__byteAddress ((SELF), (INDEX)) & ~Sbitset__bit_mask (INDEX);     \
+} while(0)
+
+/* NBITS is the size of the bitset.  More than NBITS bits might be reset.  */
+#define Sbitset__zero(SELF, NBITS)                                            \
+do {                                                                          \
+  memset (SELF, 0, Sbitset__nbytes (NBITS));                                  \
+} while(0)
+
+/* NBITS is the size of the bitset.  More than NBITS bits might be set.  */
+#define Sbitset__ones(SELF, NBITS)                                            \
+do {                                                                          \
+  memset (SELF, 0xff, Sbitset__nbytes (NBITS));                               \
+} while(0)
+
+/* NBITS is the size of every bitset.  More than NBITS bits might be set.  */
+#define Sbitset__or(SELF, OTHER1, OTHER2, NBITS)                              \
+do {                                                                          \
+  char *ptr_self = (SELF);                                                    \
+  char *ptr_other1 = (OTHER1);                                                \
+  char *ptr_other2 = (OTHER2);                                                \
+  char *end_self = ptr_self + Sbitset__nbytes (NBITS);                        \
+  for (; ptr_self < end_self; ++ptr_self, ++ptr_other1, ++ptr_other2)         \
+    *ptr_self = *ptr_other1 | *ptr_other2;                                    \
+} while(0)
+
+#define SBITSET__FOR_EACH(SELF, NBITS, ITER, INDEX)                           \
+  for ((ITER) = (SELF); (ITER) < (SELF) + Sbitset__nbytes (NBITS); ++(ITER))  \
+    if (*(ITER) != 0)                                                         \
+      for ((INDEX) = ((ITER)-(SELF))*8;                                       \
+           (INDEX) < (NBITS) && (SELF)+(INDEX)/8 < (ITER)+1;                  \
+           ++(INDEX))                                                         \
+        if (((*ITER) & Sbitset__bit_mask (INDEX)) != 0)
+
+#endif /* !SBITSET_H_ */