Lout 3.17.

git-svn-id: http://svn.savannah.nongnu.org/svn/lout/trunk@2 9365b830-b601-4143-9ba8-b4a8e2c3339c

1 files changed, 192 insertions, 0 deletions

diff --git a/z30.c b/z30.c
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+/*@z30.c:Symbol uses:InsertUses()@********************************************/
+/*                                                                           */
+/*  THE LOUT DOCUMENT FORMATTING SYSTEM (VERSION 3.17)                       */
+/*  COPYRIGHT (C) 1991, 1999 Jeffrey H. Kingston                             */
+/*                                                                           */
+/*  Jeffrey H. Kingston (jeff@cs.usyd.edu.au)                                */
+/*  Basser Department of Computer Science                                    */
+/*  The University of Sydney 2006                                            */
+/*  AUSTRALIA                                                                */
+/*                                                                           */
+/*  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 2, 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, write to the Free Software              */
+/*  Foundation, Inc., 59 Temple Place, Suite 330, Boston MA 02111-1307 USA   */
+/*                                                                           */
+/*  FILE:         z30.c                                                      */
+/*  MODULE:       Symbol Uses                                                */
+/*  EXTERNS:      InsertUses(), FlattenUses(), SearchUses(),                 */
+/*                FirstExternTarget(), NextExternTarget()                    */
+/*                                                                           */
+/*****************************************************************************/
+#include "externs.h"
+
+
+/*****************************************************************************/
+/*                                                                           */
+/*  InsertUses(x, y)                                                         */
+/*                                                                           */
+/*  Record the fact that symbol x uses symbol y, by linking them.            */
+/*  Increment count of the number of times y is used, if y is a parameter.   */
+/*                                                                           */
+/*****************************************************************************/
+
+void InsertUses(OBJECT x, OBJECT y)
+{ OBJECT tmp;
+  debug2(DSU, D, "InsertUses( %s, %s )", SymName(x), SymName(y));
+  if( type(x) == LOCAL && type(y) == LOCAL && !predefined(y) )
+  { GetMem(tmp, USES_SIZE, no_fpos);  item(tmp) = y;
+    if( base_uses(x) == nilobj )  next(tmp) = tmp;
+    else next(tmp) = next(base_uses(x)), next(base_uses(x)) = tmp;
+    base_uses(x) = tmp;
+  }
+  if( is_par(type(y)) )
+  {
+    uses_count(y) += (enclosing(y) == x ? 1 : 2);
+    if( dirty(y) || uses_count(y) > 1 )  dirty(enclosing(y)) = TRUE;
+  }
+  else if( sym_body(y) == nilobj || dirty(y) )  dirty(x) = TRUE;
+  debug5(DSU, D, "InsertUses returning ( %s %s; %s %s, count = %d )",
+    SymName(x), (dirty(x) ? "dirty" : "clean"),
+    SymName(y), (dirty(y) ? "dirty" : "clean"), uses_count(y));
+} /* end InsertUses */
+
+
+/*@::GatherUses(), GatherAllUses(), FlattenUses()@****************************/
+/*                                                                           */
+/*  static GatherUses(x, sym)                                                */
+/*  static GatherAllUses(x)                                                  */
+/*                                                                           */
+/*  GatherUses adds all the unmarked descendants of x to the uses relation   */
+/*  of sym;  GatherAllUses applies gather_uses to all descendants of x.      */
+/*                                                                           */
+/*****************************************************************************/
+
+static void GatherUses(OBJECT x, OBJECT sym)
+{ OBJECT link, y, tmp;
+  if( base_uses(x) != nilobj )
+  { link = next(base_uses(x));
+    do
+    { y = item(link);
+      if( marker(y) != sym )
+      {	if( y != sym )
+	{ marker(y) = sym;
+	  GetMem(tmp, USES_SIZE, no_fpos);  item(tmp) = y;
+	  if( uses(sym) == nilobj )  next(tmp) = tmp;
+	  else next(tmp) = next(uses(sym)), next(uses(sym)) = tmp;
+	  uses(sym) = tmp;
+	  if( indefinite(y) )  indefinite(sym) = TRUE;
+	  if( uses_extern_target(y) )  uses_extern_target(sym) = TRUE;
+	  GatherUses(y, sym);
+	}
+	else recursive(sym) = TRUE;
+      }
+      link = next(link);
+    } while( link != next(base_uses(x)) );
+  }
+} /* end GatherUses */
+
+
+static void GatherAllUses(OBJECT x)
+{ OBJECT link, y;
+  for( link = Down(x);  link != x;  link = NextDown(link) )
+  { Child(y, link);
+    if( type(y) == LOCAL )  GatherUses(y, y);
+    GatherAllUses(y);
+  }
+} /* end GatherAllUses */
+
+
+/*****************************************************************************/
+/*                                                                           */
+/*  FlattenUses()                                                            */
+/*                                                                           */
+/*  Traverse the directed graph assembled by InsertUses, finding its         */
+/*  transitive closure and storing this explicitly in uses(x) for all x.     */
+/*                                                                           */
+/*****************************************************************************/
+
+void FlattenUses(void)
+{ GatherAllUses(StartSym);
+} /* end FlattenUses */
+
+
+/*@::SearchUses(), FirstExternTarget(), NextExternTarget()@*******************/
+/*                                                                           */
+/*  BOOLEAN SearchUses(x, y)                                                 */
+/*                                                                           */
+/*  Discover whether symbol x uses symbol y by searching the uses list of x. */
+/*                                                                           */
+/*****************************************************************************/
+
+BOOLEAN SearchUses(OBJECT x, OBJECT y)
+{ OBJECT p;
+  debug3(DSU, DD, "SearchUses(%s, %s) uses: %d", SymName(x),SymName(y),uses(x));
+  if( x == y )  return TRUE;
+  if( uses(x) != nilobj )
+  { p = next(uses(x));
+    do
+    { debug1(DSU, DDD, "  checking %s", SymName(item(p)));
+      if( item(p) == y )  return TRUE;
+      p = next(p);
+    } while( p != next(uses(x)) );
+  }
+  return FALSE;
+} /* end SearchUses */
+
+
+/*****************************************************************************/
+/*                                                                           */
+/*  OBJECT FirstExternTarget(sym, cont)                                      */
+/*  OBJECT NextExternTarget(sym, cont)                                       */
+/*                                                                           */
+/*  Together these two procedures return all symbols which are both used by  */
+/*  sym and a target for at least one external galley.  Return nilobj at end.*/
+/*                                                                           */
+/*****************************************************************************/
+
+OBJECT FirstExternTarget(OBJECT sym, OBJECT *cont)
+{ OBJECT res;
+  debug1(DSU, D, "FirstExternTarget( %s )", SymName(sym));
+  res = nilobj;  *cont = nilobj;
+  if( is_extern_target(sym) )  res = sym;
+  else if( uses(sym) != nilobj )
+  { *cont = next(uses(sym));
+    do
+    { if( is_extern_target(item(*cont)) )
+      {	res = item(*cont);
+	break;
+      }
+      *cont = next(*cont);
+    } while( *cont != next(uses(sym)) );
+  }
+  debug1(DSU, D, "FirstExternTarget returning %s", SymName(res));
+  return res;
+} /* end FirstExternTarget */
+
+OBJECT NextExternTarget(OBJECT sym, OBJECT *cont)
+{ OBJECT res;
+  debug1(DSU, D, "NextExternTarget( %s )", SymName(sym));
+  res = nilobj;
+  if( *cont != nilobj )
+  { *cont = next(*cont);
+    while( *cont != next(uses(sym)) )
+    { if( is_extern_target(item(*cont)) )
+      {	res = item(*cont);
+	break;
+      }
+      *cont = next(*cont);
+    }
+  }
+  debug1(DSU, D, "NextExternTarget returning %s", SymName(res));
+  return res;
+} /* end NextExternTarget */