o_cse.sa

 
---------------------------> Sather 1.1 source file <--------------------------

class CSE_DOUBLE_EXPRS < $HASH 
class CSE_DOUBLE_EXPRS < $HASH is
   include COMPARABLE;
   readonly attr expr:FLIST{$AM_EXPR};
   readonly attr pos:FLIST{AM_CURSOR};
   readonly attr locals:FLIST{AM_LOCAL_EXPR};

   create(e:$AM_EXPR,c:AM_CURSOR):SAME is 
      r::=new;
      r.expr:=r.expr.push(e);-- CSE_DOUBLE_EXPRS::expr CSE_DOUBLE_EXPRS::expr FLIST{1}::push
      r.pos:=r.pos.push(#(c));-- CSE_DOUBLE_EXPRS::pos CSE_DOUBLE_EXPRS::pos FLIST{1}::push AM_CURSOR::create
      r.locals:=r.locals.push(void);-- CSE_DOUBLE_EXPRS::locals CSE_DOUBLE_EXPRS::locals FLIST{1}::push
      return r;
   end;

   add_loc(e:$AM_EXPR,c:AM_CURSOR) is
      expr:=expr.push(e);-- CSE_DOUBLE_EXPRS::expr CSE_DOUBLE_EXPRS::expr FLIST{1}::push
      pos:=pos.push(#(c));-- CSE_DOUBLE_EXPRS::pos CSE_DOUBLE_EXPRS::pos FLIST{1}::push AM_CURSOR::create
      locals:=locals.push(void);-- CSE_DOUBLE_EXPRS::locals CSE_DOUBLE_EXPRS::locals FLIST{1}::push
   end;

   hash:INT is return expr[0].hash; end;-- CSE_DOUBLE_EXPRS::expr FLIST{1}::aget
   is_eq(e:CSE_DOUBLE_EXPRS):BOOL is return expr[0] = e.expr[0]; end;-- CSE_DOUBLE_EXPRS::expr FLIST{1}::aget CSE_DOUBLE_EXPRS::expr FLIST{1}::aget
   is_neq(e:CSE_DOUBLE_EXPRS):BOOL is return ~(expr[0] = e.expr[0]); end;
end;


class OPT_CSE 
class OPT_CSE is
   include OPT_HELPER;

   remove_cse(func:AM_ROUT_DEF) is
      c::=#AM_CURSOR(prog,func.code);-- AM_CURSOR::create OPT_CSE::prog AM_ROUT_DEF::code
      c.ignore_pre:=true;-- AM_CURSOR::ignore_pre
      c.ignore_post:=true;-- AM_CURSOR::ignore_post
      c.ignore_assert:=true;-- AM_CURSOR::ignore_assert
      c.assign_in_order:=true;-- AM_CURSOR::assign_in_order
      exprs:FSET{CSE_DOUBLE_EXPRS};
      replacements:FLIST{TUP{AM_CURSOR,$AM_EXPR}};
      found_double::=false;

      loop
	 if prog.opt_debug then-- OPT_CSE::prog PROG::opt_debug
	    #OUT+"O:CSE: current C: "+c.str;-- OUT::create OUT::plus OUT::plus AM_CURSOR::str
	 end;
         am::=c.next!;-- AM_CURSOR::next!
	 if prog.opt_debug then-- OPT_CSE::prog PROG::opt_debug
	    #OUT+"O_CSE: "+SYS::str_for_tp(SYS::tp(am))+"\n";-- OUT::create OUT::plus OUT::plus SYS::str_for_tp SYS::tp OUT::plus
	    #OUT+"current C: "+c.str;-- OUT::create OUT::plus OUT::plus AM_CURSOR::str
	 end;
	 typecase am
	 -- some expressions are never replaced with locals
	 when AM_LOCAL_EXPR then 
	 when AM_GLOBAL_EXPR then 
	 when AM_CLUSTER_EXPR then 
	 when AM_HERE_EXPR then 
	 when $AM_CONST then 
	 when $AM_EXPR then
	    if ~c.is_current_lhs and ~void(am.tp) then-- AM_CURSOR::is_current_lhs BOOL::not BOOL::not
	       e:CSE_DOUBLE_EXPRS:=#(am,c);-- CSE_DOUBLE_EXPRS::create
	       ee::=exprs.get(e);-- FSET{1}::get
	       if void(ee) then
		  exprs:=exprs.insert(e);-- FSET{1}::insert
		  if prog.opt_debug then-- OPT_CSE::prog PROG::opt_debug
		     #OUT+"inserting into CSE stack: ";AM_OUT::AM_out(am);#OUT+"\n";-- OUT::create OUT::plus AM_OUT::AM_out OUT::create OUT::plus
		  end;
	       else
		  e:=ee;
		  done::=false;
		  loop
		     i::=e.pos.ind!;-- CSE_DOUBLE_EXPRS::pos FLIST{1}::ind!
		     if SYS::id(e.expr[i])/=SYS::id(am) and-- SYS::id CSE_DOUBLE_EXPRS::expr FLIST{1}::aget INT::is_eq SYS::id BOOL::not
		       c.is_exec_after_and_const_from_there(e.pos[i],am) then-- AM_CURSOR::is_exec_after_and_const_from_there CSE_DOUBLE_EXPRS::pos FLIST{1}::aget
			if void(e.locals[i]) then-- CSE_DOUBLE_EXPRS::locals FLIST{1}::aget
			   e.locals[i]:=new_local(func,am.tp,am.source);-- CSE_DOUBLE_EXPRS::locals FLIST{1}::aset OPT_CSE::new_local
			   as::=#AM_ASSIGN_STMT(e.locals[i].source);-- AM_ASSIGN_STMT::create CSE_DOUBLE_EXPRS::locals FLIST{1}::aget AM_LOCAL_EXPR::source
			   as.dest:=e.locals[i];-- AM_ASSIGN_STMT::dest CSE_DOUBLE_EXPRS::locals FLIST{1}::aget
			   as.src:=e.expr[i];-- AM_ASSIGN_STMT::src CSE_DOUBLE_EXPRS::expr FLIST{1}::aget
			   st::=#AM_STMT_EXPR(e.locals[i].source);-- AM_STMT_EXPR::create CSE_DOUBLE_EXPRS::locals FLIST{1}::aget AM_LOCAL_EXPR::source
			   st.stmts:=as;-- AM_STMT_EXPR::stmts
			   st.expr:=e.locals[i];-- AM_STMT_EXPR::expr CSE_DOUBLE_EXPRS::locals FLIST{1}::aget
			   replacements:=replacements.push(#TUP{AM_CURSOR,$AM_EXPR}(e.pos[i],st))-- FLIST{1}::push TUP{2}::create CSE_DOUBLE_EXPRS::pos FLIST{1}::aget
			end;
			prog.stat.incr("O: # of cse");-- OPT_CSE::prog PROG::stat
			if prog.opt_debug then-- OPT_CSE::prog PROG::opt_debug
			   #OUT+"replacing  ";-- OUT::create OUT::plus
			   AM_OUT::AM_out(am);-- AM_OUT::AM_out
			   #OUT+"  with ";AM_OUT::AM_out(e.locals[i]);-- OUT::create OUT::plus AM_OUT::AM_out CSE_DOUBLE_EXPRS::locals FLIST{1}::aget
			   #OUT+"\n";-- OUT::create OUT::plus
			end;
			replacements:=replacements.push(#TUP{AM_CURSOR,$AM_EXPR}(#(c),e.locals[i]));-- FLIST{1}::push TUP{2}::create AM_CURSOR::create CSE_DOUBLE_EXPRS::locals FLIST{1}::aget
			done:=true;
			break!;
		     end;
		  end;
		  if ~done then-- BOOL::not
		     if prog.opt_debug then #OUT+"add_loc CSE stack: ";AM_OUT::AM_out(am);#OUT+"\n"; end;-- OPT_CSE::prog PROG::opt_debug OUT::create OUT::plus AM_OUT::AM_out OUT::create OUT::plus
		     e.add_loc(am,c);-- CSE_DOUBLE_EXPRS::add_loc
		  end;
	       end;
	    end;
	 else
	 end;
      end;
      if ~void(replacements) then-- BOOL::not
	 loop
	    tp::=replacements.elt!;-- FLIST{1}::elt!
	    if prog.opt_debug then-- OPT_CSE::prog PROG::opt_debug
	       #OUT+"replacing (lhs="+tp.t1.is_current_lhs+"):";-- OUT::create OUT::plus OUT::plus TUP{2}::t1 AM_CURSOR::is_current_lhs OUT::plus
	       AM_OUT::AM_out(tp.t1.cur);-- AM_OUT::AM_out TUP{2}::t1 AM_CURSOR::cur
	       #OUT+"\nwith: ";-- OUT::create OUT::plus
	       AM_OUT::AM_out(tp.t2);-- AM_OUT::AM_out TUP{2}::t2
	       #OUT+"\n";-- OUT::create OUT::plus
	    end;
	    tp.t1.replace_expr(tp.t2);-- TUP{2}::t1 AM_CURSOR::replace_expr TUP{2}::t2
	 end;
	 SYS::destroy(replacements);-- SYS::destroy
      end;
      if ~void(exprs) then SYS::destroy(exprs); end;-- BOOL::not SYS::destroy
   end;
end;

-- vim:sw=3:nosmartindent