Panasonic MN1030 user manual Example subroutine call converted to a relative branch

Chapter 4 Optimization

Example: subroutine call converted to a relative branch

This section gives an example of a CALLS LABEL instruction with a target address within the range of a relative jump--that is, between -32,768 and +32,767 from the current program counter.

The source list is as follows.

	opt	on
_TEXT	section	CODE, PUBLIC,1
sub_func
addr_set	calls	func_end
	org	addr_set+128
func_end	rts
	end

The final list file after assembly is shown next. Since the CALLS LABEL instruction in line four con- tains a target address that may be expressed with a 2-byte relative branch, the assembler replaces it with the CALLS LABEL variant with a 2-byte address field. Note that the mnemonics and object code are different.

			opt4.lst Page 1
Loc	*** PanaX series Series MN1030 Cross Assembler ***
	Object	Line	Source	opt	on
		1	_TEXT
40000000		2		section	CODE, PUBLIC, 1
	FAFF8000	3	sub_func	Calls	func_end
40000000		@4	addr_set
		5		org	addr_set+128
40000080		6	func_end
	F0FC	7		rts
40000080		8
		9		end
*** Symbol	Table	***	opt4.lst Page 2
	40000000	T	sub_func
	40000000	T	addr_set
	40000080	T	func_end

58 Usage Example