--- pgp/src/68000_32.s	2018/04/24 16:41:17	1.1.1.3
+++ pgp/src/68000_32.s	2018/04/24 16:45:46	1.1.1.5
@@ -124,41 +124,52 @@ P_ROTL:     move.b  d0,d1       ;boolean
 .base:      scs     d0              ;set returned carry
             rts
 
-            
+
 ;void P_SETP(short nbits);
 ; /* sets working precision to specified number of bits. */
 ; /* only to minimize portation differences              */
 ;Parameters: --
 ;Result:     --
-         
+
 P_SETP:		rts
 
-; ***NOT TESTED***
-;
 ;void P_SMUL(MULTUNIT *prod, MULTUNIT *multiplicand, MULTUNIT multiplier)
 ; /* multiprecision multiply */
 ;Parameters: A0.l: prod, A1.l: multiplicand, D0.w: multiplier
 ;Modifies: D0-D3/A0-A1
 ;Result:     --
 
-P_SMUL: move.w  global_precision,d3
-        lsl.w   #1,d3
-        subq.w  #1,d3
-        clr.l   d2
-        clr.l   d1
-
-.loop:  move.w  -(a1),d1
-        mulu.l  d0,d1
-        add.l   d2,d1
-        add.w   d1,-(a0)
-        scs     d2
-        lsr.l   #16,d1
-        add.w   d1,d2
-        dbf     d3,.loop
-
-        move.w  d2,(a0)
-        rts
-
-
-            END
+; Copied from 3B168000.S (GG)
+P_SMUL:     ;mov.l   4(sp),a0	;# fetch first argument: prod
+	;PureC already puts arguments there (GG)
+	    ;mov.l   8(sp),a1	;# fetch second argument: multiplicand
+	    ;mov.l   12(sp),d0	;# fetch third argument: multiplier
+	    ;mov.l   d2,-(sp)	;# save d2 -- not a Unix-PC scratch reg
+;	(OK for PureC -- GG)
+	    move.l   d3,-(sp)  ;# save d3 -- not a Unix-PC scratch reg
+	    move.l   d4,-(sp)  ;# save d4 -- not a Unix-PC scratch reg
+	clr.l	d2		;# clear the carry register
+	clr.l	d4		;# clear upper half of temp reg for prod
+	adda.w	#2,a0		;# position prod to 1 beyond LSB
+	adda.w	#2,a1		;# position multiplicand to 1 beyond LSB
+	move.w	global_precision,d3  ;# fetch size of multiplicand
+	add.w	d3,d3	; GG: convert 32bit to 16bit units
+	bra	ddbf1
+
+dloop:	move.w	-(a1),d1	;# fetch multiplicand
+	mulu.w	d0,d1		;# multiply by multiplier
+	move.w	-(a0),d4	;# fetch prod
+	add.l	d4,d1		;# add in prod
+	add.l	d2,d1		;# add in carry
+	move.w	d1,(a0)	;# store result back to prod
+	swap.w	d1		;# fetch carry info (upper 16 bits of mult)
+	move.w	d1,d2		;# and move it into carry
+ddbf1:	dbf	d3,dloop
+
+	move.w	d2,-(a0)	;# store carry
+	move.l	(sp)+,d4
+	move.l	(sp)+,d3
+;	move.l	(sp)+,d2
+	rts
 
+	END