| /*@z30.c:Symbol uses:InsertUses()@********************************************/ |
| /* */ |
| /* THE LOUT DOCUMENT FORMATTING SYSTEM (VERSION 3.24) */ |
| /* COPYRIGHT (C) 1991, 2000 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 */ |
