* src/lalr.c (traverse, digraph, matrix_print, transpose): Move

to... * src/relation.h, src/relation.c (traverse, relation_digraph) (relation_print, relation_transpose): New.
2026-03-13 14:23:04 +00:00 · 2002-06-30 17:31:51 +00:00
parent 24c7d80020
commit 0e4d575330
5 changed files with 244 additions and 158 deletions
--- a/src/relation.c
+++ b/src/relation.c
@@ -0,0 +1,181 @@
+/* Binary relations.
+   Copyright (C) 2002  Free Software Foundation, Inc.
+
+   This file is part of Bison, the GNU Compiler Compiler.
+
+   Bison 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 2, or (at your option)
+   any later version.
+
+   Bison 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 Bison; see the file COPYING.  If not, write to
+   the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include "system.h"
+#include "bitsetv.h"
+#include "relation.h"
+#include "getargs.h"
+
+void
+relation_print (relation_t relation, size_t size, FILE *out)
+{
+  unsigned i, j;
+
+  for (i = 0; i < size; ++i)
+    {
+      fprintf (out, "%3d: ", i);
+      if (relation[i])
+	for (j = 0; relation[i][j] != -1; ++j)
+	  fprintf (out, "%3d ", relation[i][j]);
+      fputc ('\n', out);
+    }
+  fputc ('\n', out);
+}
+
+
+/*---------------------------------------------------------------.
+| digraph & traverse.                                            |
+|                                                                |
+| The following variables are used as common storage between the |
+| two.                                                           |
+`---------------------------------------------------------------*/
+
+static relation_t R;
+static relation_nodes_t INDEX;
+static relation_nodes_t VERTICES;
+static int top;
+static int infinity;
+static bitsetv F;
+
+static void
+traverse (int i)
+{
+  int j;
+  int height;
+
+  VERTICES[++top] = i;
+  INDEX[i] = height = top;
+
+  if (R[i])
+    for (j = 0; R[i][j] >= 0; ++j)
+      {
+	if (INDEX[R[i][j]] == 0)
+	  traverse (R[i][j]);
+
+	if (INDEX[i] > INDEX[R[i][j]])
+	  INDEX[i] = INDEX[R[i][j]];
+
+	bitset_or (F[i], F[i], F[R[i][j]]);
+      }
+
+  if (INDEX[i] == height)
+    for (;;)
+      {
+	j = VERTICES[top--];
+	INDEX[j] = infinity;
+
+	if (i == j)
+	  break;
+
+	bitset_copy (F[j], F[i]);
+      }
+}
+
+
+void
+relation_digraph (relation_t relation, size_t size,
+		  bitsetv *function)
+{
+  unsigned i;
+
+  infinity = size + 2;
+  INDEX = XCALLOC (relation_node_t, size + 1);
+  VERTICES = XCALLOC (relation_node_t, size + 1);
+  top = 0;
+
+  R = relation;
+  F = *function;
+
+  for (i = 0; i < size; i++)
+    INDEX[i] = 0;
+
+  for (i = 0; i < size; i++)
+    if (INDEX[i] == 0 && R[i])
+      traverse (i);
+
+  XFREE (INDEX);
+  XFREE (VERTICES);
+
+  *function = F;
+}
+
+
+/*-------------------------------------------.
+| Destructively transpose R_ARG, of size N.  |
+`-------------------------------------------*/
+
+void
+relation_transpose (relation_t *R_arg, int n)
+{
+  /* The result. */
+  relation_t new_R = XCALLOC (relation_nodes_t, n);
+  /* END_R[I] -- next entry of NEW_R[I]. */
+  relation_t end_R = XCALLOC (relation_nodes_t, n);
+  /* NEDGES[I] -- total size of NEW_R[I]. */
+  int *nedges = XCALLOC (int, n);
+  int i, j;
+
+  if (trace_flag)
+    {
+      fputs ("relation_transpose: input\n", stderr);
+      relation_print (*R_arg, n, stderr);
+    }
+
+  /* Count. */
+  for (i = 0; i < n; i++)
+    if ((*R_arg)[i])
+      for (j = 0; (*R_arg)[i][j] >= 0; ++j)
+	++nedges[(*R_arg)[i][j]];
+
+  /* Allocate. */
+  for (i = 0; i < n; i++)
+    if (nedges[i] > 0)
+      {
+	relation_node_t *sp = XCALLOC (relation_node_t, nedges[i] + 1);
+	sp[nedges[i]] = -1;
+	new_R[i] = sp;
+	end_R[i] = sp;
+      }
+
+  /* Store. */
+  for (i = 0; i < n; i++)
+    if ((*R_arg)[i])
+      for (j = 0; (*R_arg)[i][j] >= 0; ++j)
+	{
+	  *end_R[(*R_arg)[i][j]] = i;
+	  ++end_R[(*R_arg)[i][j]];
+	}
+
+  free (nedges);
+  free (end_R);
+
+  /* Free the input: it is replaced with the result. */
+  for (i = 0; i < n; i++)
+    XFREE ((*R_arg)[i]);
+  free (*R_arg);
+
+  if (trace_flag)
+    {
+      fputs ("relation_transpose: output\n", stderr);
+      relation_print (new_R, n, stderr);
+    }
+
+  *R_arg = new_R;
+}