MZ is back!HEADmain

1 files changed, 31 insertions, 0 deletions

diff --git a/v4.0/src/BIOS/JUMPMAC.INC b/v4.0/src/BIOS/JUMPMAC.INC
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+                                                  ;;Rev 3.30 Modification
+;
+; given a label <lbl> either 2 byte jump to another label <lbl>_J
+; if it is near enough or 3 byte jump to <lbl>
+;
+
+jump    macro lbl
+        local a
+.xcref
+
+        ifndef lbl&_j                   ;; is this the first invocation
+a:
+                                JMP lbl
+        ELSE
+            IF (lbl&_J GE $) OR ($-lbl&_J GT 126)
+a:
+                                JMP lbl ;; is the jump too far away?
+            ELSE
+a:
+                               JMP lbl&_J  ;; do the short one...
+            ENDIF
+        ENDIF
+lbl&_j = a
+.cref
+        endm
+.xcref  jump
+;REDEFINE THE ABOVE MACRO TO ALWAYS TRY A 3 BYTE NEAR JUMP               
+JUMP MACRO LBL                                                           
+                                        JMP LBL                          
+        ENDM                                    ;;End of Modification
+
\ No newline at end of file