Initial data commit

Task/Conditional-structures/6502-Assembly/conditional-structures-5.6502

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+ReturnTable:
+dw foo-1            ;each is a label to a section of code that ends in an RTS
+dw bar-1
+dw baz-1
+
+ReturnSpoof:        ;assume execution arrived here via a JSR command.
+lda indexVariable   ;contains the desired index into ReturnTable. 0 = foo, 1 = bar, 2 = baz.
+asl                 ;the data is word length so the index must be multiplied by 2.
+tax
+
+lda ReturnTable+1,x ;get the high byte of the return address.
+pha
+lda ReturnTable,x   ;get the low byte
+pha
+
+; Now, the desired subroutine's address minus 1 is on top of the stack.
+; The RTS command will take this address and jump there. That routine's RTS command will act as the RTS from "ReturnSpoof",
+; bringing execution to the point just after ReturnSpoof was called.
+; If done properly, return spoofing will not corrupt the stack.
+
+RTS                 ;this "RTS" acts as a JMP to the address we just put on the stack.