.bp
.NH
Appendix B: Translation of a \fBPAR\fP construct to EM code using the library
routines to simulate parallelism 
.PP
Translation of the parallel construct:
.DS
.ft 5
	par
		P0
		par i = [ 1 for n ]
			P(i)
.DE
is
.TS
center;
lf5 lf5.
 lal -20	; Assume 20 bytes of local variables at this moment
 cal $parbegin	; Set up a process group
 asp 4		; Assume pointersize = 4
 cal $parfork	; Split stack in two from local -20
 lfr 4		; Assume wordsize = 4
 zne *23	; One end jumps to second process, other continues here
 lor 0	; Static link
 cal $P0
 asp 4
 bra *24	; Jump to the outer parend
23
 cal $parfork	; Fork off `par i = ...'  process
 lfr 4
 zne *25	; One end jumps to end of outer par
 lal -20	; Place break just above i
 cal $parbegin	; Set up another process group for the P(i)
 loc 1
 stl -24	; i:=1
 lol n	; Assume n can be addressed this simply
 stl -28	; A nameless counter
 bra *26	; Branch to counter test
27
 cal $parfork	; Fork off one P(i)
 lfr 4
 zne *28	; One jumps away to increment i, the other calls P(i)
 lol -24
 lor 0
 cal $P
 asp 8
 bra *29
28
 inl -24	; i:=i+1
 del -28	; counter:=counter-1
26
 lol -28
 zgt *27	; while counter>0 repeat loop
29
 cal $parend	; Wait for the P(i) to finish, then delete group
 bra *24	; Jump to the higher up meeting place with P0
25	; Note that the bra will be optimized away
24
 cal $parend	; Wait for both processes to end, then delete group
.TE