all screen control codes are now handled via jumptable

STATUS.md

@@ -178,7 +178,6 @@ Not all of them - only these we want to have implemented.
 | `$F646`   | IEC close                    | NOT DONE |                                                    |
 | `$FD30`   | default vectors              | DONE     |                                                    |
 | `$FD90`   | (unknown)                    | NOT DONE |                                                    |
-| `$FD90`   | (unknown)                    | NOT DONE |                                                    |
 | `$FE2D`   | memtop set part              | DONE     |                                                    |
 | `$FE47`   | default NMI                  | PARTIAL  |                                                    |
 | `$FE66`   | default BRK                  | DONE     |                                                    |

c64/kernal/screen/chrout_screen_control.s

@@ -7,62 +7,32 @@ chrout_screen_control:
 
 	txa
 
-	// Order here is not random
-	// 1. First handle the ones that do not depend on quote mode
-	// 2. Handle remaining control codes starting from the most commonly used
-	// We want to be as snappy as possible
-
-chrout_try_RETURN:
-
-	cmp #KEY_RETURN
-	bne !+
-
-	// RETURN clears quote and insert modes, it also clears reverse flag
-	lda #$00
-	sta QTSW
-	sta INSRT
-	sta RVS
-	jmp chrout_screen_advance_to_next_line
-!:
-chrout_try_DEL:
-
-	cmp #KEY_DEL
-	beq_far chrout_screen_DEL
-
-chrout_try_INS:
-
-	cmp #KEY_INS
-	beq_far chrout_screen_INS
-
-#if CONFIG_EDIT_STOPQUOTE
-chrout_try_STOP:
-
-	cmp #KEY_STOP
-	bne !+
-	
-	lda #$00
-	sta QTSW
-	sta INSRT
-	// Let it run, we are saving 3 bytes on JMP this way
-	// and the performance hit is not going to be visible nevertheless
-!:
-#endif
-chrout_try_quote:
-
-	lda QTSW
-	ora INSRT
-	beq !+
-	txa
-	jmp chrout_screen_quote
-!:
-	txa
-
 chrout_try_jumptable:
 
 	ldx #(__chrout_screen_jumptable_codes_end - chrout_screen_jumptable_codes - 1)
+
 chrout_try_jumptable_loop:
+
+	cpx #(__chrout_screen_jumptable_quote_guard - chrout_screen_jumptable_codes - 1)
+	bne chrout_try_jumptable_loop_noquote
+
+	// Is this insert/quote mode?
+	tay
+	lda QTSW
+	ora INSRT
+	beq !+
+	tya
+	jmp chrout_screen_quote
+!:
+	tya
+
+	// FALLTROUGH
+
+chrout_try_jumptable_loop_noquote:
+
 	cmp chrout_screen_jumptable_codes, x
 	bne !+
+
 	// Found, perform a jump to subroutine
 	lda chrout_screen_jumptable_hi, x
 	pha
@@ -76,7 +46,9 @@ chrout_try_jumptable_loop:
 chrout_try_COLOR:
 
 	ldx #$0F
+
 chrout_try_color_loop:
+
 	cmp colour_codes,x
 	bne !+
 	stx COLOR

c64/kernal/screen/chrout_screen_jumptable_codes.s

@@ -1,7 +1,7 @@
 
 //
 // Jumptable for screen control coldes support. To improve performance, should be sorted
-// starting from the least probable routine
+// starting from the least probable routine.
 //
 
 
@@ -20,6 +20,15 @@ chrout_screen_jumptable_codes:
 	.byte KEY_CRSR_DOWN
 	.byte KEY_CRSR_UP
 
+__chrout_screen_jumptable_quote_guard:
+
+#if CONFIG_EDIT_STOPQUOTE
+	.byte KEY_STOP
+#endif
+	.byte KEY_INS
+	.byte KEY_DEL
+	.byte KEY_RETURN
+
 __chrout_screen_jumptable_codes_end:
 
 
@@ -37,7 +46,12 @@ chrout_screen_jumptable_lo:
 	.byte <(chrout_screen_CRSR_LEFT  - 1)
 	.byte <(chrout_screen_CRSR_DOWN  - 1)
 	.byte <(chrout_screen_CRSR_UP    - 1)
-
+#if CONFIG_EDIT_STOPQUOTE
+	.byte <(chrout_screen_STOP       - 1)
+#endif
+	.byte <(chrout_screen_INS        - 1)
+	.byte <(chrout_screen_DEL        - 1)
+	.byte <(chrout_screen_RETURN     - 1)
 
 chrout_screen_jumptable_hi:
 
@@ -53,3 +67,9 @@ chrout_screen_jumptable_hi:
 	.byte >(chrout_screen_CRSR_LEFT  - 1)
 	.byte >(chrout_screen_CRSR_DOWN  - 1)
 	.byte >(chrout_screen_CRSR_UP    - 1)
+#if CONFIG_EDIT_STOPQUOTE
+	.byte >(chrout_screen_STOP       - 1)
+#endif
+	.byte >(chrout_screen_INS        - 1)
+	.byte >(chrout_screen_DEL        - 1)
+	.byte >(chrout_screen_RETURN     - 1)

c64/kernal/screen/chrout_screen_return.s

@@ -0,0 +1,14 @@
+
+//
+// RETURN key handling within CHROUT
+//
+
+
+chrout_screen_RETURN:
+
+	// RETURN clears quote and insert modes, it also clears reverse flag
+	lda #$00
+	sta QTSW
+	sta INSRT
+	sta RVS
+	jmp chrout_screen_advance_to_next_line

c64/kernal/screen/chrout_screen_stop.s

@@ -0,0 +1,18 @@
+
+//
+// STOP key handling within CHROUT
+//
+
+
+#if CONFIG_EDIT_STOPQUOTE
+
+
+chrout_screen_STOP:
+	
+	lda #$00
+	sta QTSW
+	sta INSRT
+	jmp chrout_screen_done
+
+
+#endif