some code/data size optimizations

src/aliases/,aliases_ram_lowmem_m65.s

@@ -54,7 +54,7 @@
 	!addr M65_TXTROW_OFF   = $592 ; $592-$593  offset to the current text row from the viewport start
 	!addr M65_SCRCOLMAX    = $594 ;            maximum allowed column
 	                               ; $595-$5EB  -- UNUSED --
-	!addr M65_DMAGIC_LIST  = $5EF ; $5EF-$5FF  reserved for DMAgic list, 17 bytes
+	!addr M65_DMAGIC_LIST  = $5F1 ; $5EF-$5FF  reserved for DMAgic list, 15 bytes (modulo bytes are not needed)
 	!addr M65_RS232_INBUF  = $600 ; $600-$6FF  -- reserved for RS-232 input buffer --
 	!addr M65_RS232_OUTBUF = $700 ; $700-$7FF  -- reserved for RS-232 output buffer --
 

src/basic/engine_variables/helper_cmp_fretop.s

@@ -14,9 +14,8 @@ helper_cmp_fretop:
 
 	lda DSCPNT+2
 	cmp FRETOP+1
-	beq @1    ; XXX! BNE+RTS would save one byte
+	bne @1
-	rts
-@1:
 	lda DSCPNT+1
 	cmp FRETOP+0
+@1:
 	rts

src/kernal/board_m65/mega65_dmagic.s

@@ -22,10 +22,12 @@ m65_dmagic_oper_fill:
 
 	; Set operation type
 
-	lda #($03 + $08)                   ; operation: FILL + allow interrupts
+	lda #$03                           ; operation: FILL
 	sta M65_DMAGIC_LIST+6
 
-	; XXX! put 0 into M65_DMAJOB_SRC_3 to clear the flags
+	; Put this into M65_DMAJOB_SRC_3 too - to make sure flags (4 most significant bits) are cleared
+
+	sta M65_DMAJOB_SRC_3
 
 	; Adapt the addresses, launch the job
 
@@ -42,7 +44,7 @@ m65_dmagic_oper_copy:
 
 	; Set operation type
 
-	lda #($00 + $08)                   ; operation: COPY + allow interrupts
+	lda #$00                           ; operation: COPY
 	sta M65_DMAGIC_LIST+6
 
 	; Adapt the addresses, launch the job
@@ -135,8 +137,6 @@ m65_dmagic_init:
 	lda #$00
 	sta M65_DMAGIC_LIST+5              ; <- end of options
 
-	; !XXX modulo is ignored - remove these, shift M65_DMAGIC_LIST up by 2 bytes 
+	; Modulo is never used - thus our list is 15 bytes, not 17
-	sta M65_DMAGIC_LIST+15             ; <- set modulo to 0
-	sta M65_DMAGIC_LIST+16
 
 	rts