fix exit() now actually correctly setting the return code in A

also, moved some cleanup stuff such as CLRCHN from exit() to the cleanup routine that is always called.
finally, also call the cleanup routine when  %option no_sysinit is used

codeGenCpu6502/src/prog8/codegen/cpu6502/ProgramAndVarsGen.kt

@@ -133,7 +133,6 @@ internal class ProgramAndVarsGen(
                 pha""")
         }
 
-        // make sure that on the cx16 and c64, basic rom is banked in again when we exit the program
         when(compTarget.name) {
             "cx16" -> {
                 if(options.floats)
@@ -143,17 +142,11 @@ internal class ProgramAndVarsGen(
             }
             "c64" -> {
                 asmgen.out("  jsr  p8b_main.p8s_start |  lda  #31 |  sta  $01")
-                if(!options.noSysInit)
+                asmgen.out("  jmp  sys.cleanup_at_exit")
-                    asmgen.out("  jmp  sys.cleanup_at_exit")
-                else
-                    asmgen.out("  rts")
             }
             "c128" -> {
                 asmgen.out("  jsr  p8b_main.p8s_start |  lda  #0 |  sta ${"$"}ff00")
-                if(!options.noSysInit)
+                asmgen.out("  jmp  sys.cleanup_at_exit")
-                    asmgen.out("  jmp  sys.cleanup_at_exit")
-                else
-                    asmgen.out("  rts")
             }
             else -> asmgen.jmp("p8b_main.p8s_start")
         }

compiler/res/prog8lib/atari/syslib.p8

@@ -252,9 +252,9 @@ save_SCRATCH_ZPWORD2	.word  0
         }}
     }
 
-    inline asmsub exit(ubyte returnvalue @A) {
+    asmsub exit(ubyte returnvalue @A) {
         ; -- immediately exit the program with a return code in the A register
-        ;    TODO
+        ;    TODO where to store A as exit code?
         %asm {{
             ldx  prog8_lib.orig_stackpointer
             txs

compiler/res/prog8lib/c128/syslib.p8

@@ -373,7 +373,13 @@ asmsub  init_system_phase2()  {
 asmsub  cleanup_at_exit() {
     ; executed when the main subroutine does rts
     %asm {{
-        jmp  sys.enable_runstop_and_charsetswitch
+        lda  #0
+        sta  $ff00          ; default bank 15
+        jsr  cbm.CLRCHN		; reset i/o channels
+        jsr  enable_runstop_and_charsetswitch
+_exitcode = *+1
+        lda  #0        ; exit code possibly modified in exit()
+        rts
     }}
 }
 
@@ -754,16 +760,13 @@ _longcopy
         }}
     }
 
-    inline asmsub exit(ubyte returnvalue @A) {
+    asmsub exit(ubyte returnvalue @A) {
         ; -- immediately exit the program with a return code in the A register
         %asm {{
-            lda  #0
+            sta  cleanup_at_exit._exitcode
-            sta  $ff00          ; default bank 15
-            jsr  cbm.CLRCHN		; reset i/o channels
-            jsr  sys.enable_runstop_and_charsetswitch
             ldx  prog8_lib.orig_stackpointer
             txs
-            rts		; return to original caller
+            jmp  cleanup_at_exit
         }}
     }
 

compiler/res/prog8lib/c64/syslib.p8

@@ -372,7 +372,13 @@ asmsub  init_system_phase2()  {
 asmsub  cleanup_at_exit() {
     ; executed when the main subroutine does rts
     %asm {{
-        jmp  sys.enable_runstop_and_charsetswitch
+        lda  #31
+        sta  $01        ; bank the kernal in
+        jsr  cbm.CLRCHN		; reset i/o channels
+        jsr  enable_runstop_and_charsetswitch
+_exitcode = *+1
+        lda  #0        ; exit code possibly modified in exit()
+        rts
     }}
 }
 
@@ -752,16 +758,13 @@ _longcopy
         }}
     }
 
-    inline asmsub exit(ubyte returnvalue @A) {
+    asmsub exit(ubyte returnvalue @A) {
         ; -- immediately exit the program with a return code in the A register
         %asm {{
-            lda  #31
+            sta  cleanup_at_exit._exitcode
-            sta  $01        ; bank the kernal in
-            jsr  cbm.CLRCHN		; reset i/o channels
-            jsr  sys.enable_runstop_and_charsetswitch
             ldx  prog8_lib.orig_stackpointer
             txs
-            rts		; return to original caller
+            jmp  cleanup_at_exit
         }}
     }
 

compiler/res/prog8lib/cx16/syslib.p8

@@ -1239,6 +1239,9 @@ asmsub  cleanup_at_exit() {
         lda  #4
         sta  $01        ; rom bank 4 (basic)
         stz  $2d        ; hack to reset machine code monitor bank to 0
+        jsr  cbm.CLRCHN		; reset i/o channels
+_exitcode = *+1
+        lda  #0        ; exit code possibly modified in exit()
         rts
     }}
 }
@@ -1602,10 +1605,10 @@ save_SCRATCH_ZPWORD2	.word  0
     asmsub exit(ubyte returnvalue @A) {
         ; -- immediately exit the program with a return code in the A register
         %asm {{
-            jsr  cbm.CLRCHN		; reset i/o channels
+            sta  cleanup_at_exit._exitcode
             ldx  prog8_lib.orig_stackpointer
             txs
-            rts		; return to original caller
+            jmp  cleanup_at_exit
         }}
     }
 

compiler/res/prog8lib/pet32/syslib.p8

@@ -110,6 +110,8 @@ asmsub  init_system_phase2()  {
 asmsub  cleanup_at_exit() {
     ; executed when the main subroutine does rts
     %asm {{
+_exitcode = *+1
+        lda  #0        ; exit code possibly modified in exit()
         rts
     }}
 }
@@ -345,12 +347,13 @@ save_SCRATCH_ZPWORD2	.word  0
         }}
     }
 
-    inline asmsub exit(ubyte returnvalue @A) {
+    asmsub exit(ubyte returnvalue @A) {
         ; -- immediately exit the program with a return code in the A register
         %asm {{
+            sta  cleanup_at_exit._exitcode
             ldx  prog8_lib.orig_stackpointer
             txs
-            rts		; return to original caller
+            jmp  cleanup_at_exit
         }}
     }
 

docs/source/todo.rst

@@ -1,7 +1,7 @@
 TODO
 ====
 
-keep Bool alive longer until codegen? (don't replace by UBYTE so quickly?)
+[on branch 'booleans']: keep Bool alive longer until codegen? (don't replace by UBYTE so quickly?)
 
 ...
 

examples/test.p8

@@ -1,17 +1,21 @@
-%import textio
 %zeropage basicsafe
+%option no_sysinit
 
 main {
     sub start() {
+        sub1()
+    }
 
-        cx16.r0 = 500
+    sub sub1() {
-        if cx16.r0 in 127 to 5555
+        cx16.r0++
-            cx16.r0++
+        sub2()
-
+    }
-
+    sub sub2() {
-        cx16.r0 = 50
+        cx16.r0++
-        if cx16.r0 in 5555 downto 127
+        sub3()
-            cx16.r0++
+    }
-
+    sub sub3() {
+        cx16.r0++
+        sys.exit(42)
     }
 }