feat: implement optimizations for ZX Next runtime

Author: boriel

src/arch/zxnext/library-asm/attr.asm

@@ -38,12 +38,13 @@ SET_ATTR:
     call __IN_SCREEN
     ret nc
 
+    call __ATTR_ADDR
+
 __SET_ATTR:
     ; Internal __FASTCALL__ Entry used by printing routines
+    ; HL contains the address of the ATTR cell to set
     PROC
 
-    call __ATTR_ADDR
-
 __SET_ATTR2:  ; Sets attr from ATTR_T to (HL) which points to the scr address
     ld de, (ATTR_T)    ; E = ATTR_T, D = MASK_T
 

src/arch/zxnext/library-asm/cls.asm

@@ -10,19 +10,21 @@ CLS:
 
     ld hl, 0
     ld (COORDS), hl
-    ld hl, 1821h
+    ld hl, SCR_SIZE
     ld (S_POSN), hl
     ld hl, (SCREEN_ADDR)
+    ld (DFCC), hl
     ld (hl), 0
     ld d, h
     ld e, l
     inc de
-    ld bc, 6144
+    ld bc, 6143
     ldir
 
     ; Now clear attributes
 
     ld hl, (SCREEN_ATTR_ADDR)
+    ld (DFCCL), hl
     ld d, h
     ld e, l
     inc de
@@ -35,4 +37,3 @@ CLS:
     ENDP
 
     pop namespace
-

src/arch/zxnext/library-asm/in_screen.asm

@@ -5,19 +5,18 @@
 
 __IN_SCREEN:
     ; Returns NO carry if current coords (D, E)
-    ; are OUT of the screen limits (MAXX, MAXY)
+    ; are OUT of the screen limits
 
     PROC
     LOCAL __IN_SCREEN_ERR
 
-    ld hl, MAXX
+    ld hl, SCR_SIZE
     ld a, e
-    cp (hl)
+    cp l
     jr nc, __IN_SCREEN_ERR	; Do nothing and return if out of range
 
     ld a, d
-    inc hl
-    cp (hl)
+    cp h
     ret c                       ; Return if carry (OK)
 
 __IN_SCREEN_ERR: