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84 lines
1.4 KiB
ArmAsm
84 lines
1.4 KiB
ArmAsm
;;; Test 68HC12 FAR trampoline generation
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;;; 2 trampolines are generated:
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;;; - one for '_far_bar'
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;;; - one for '_far_foo'
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;;; 'far_no_tramp' does not have any trampoline generated.
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;;;
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.sect .text
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.globl _start
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_start:
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start:
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lds #stack-1
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ldx #0xabcd
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pshx
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ldd #0x1234
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ldx #0x5678
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bsr _far_bar ; Call to trampoline generated code
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cpx #0x1234
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bne fail ; X and D preserved (swapped by _far_bar)
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cpd #0x5678
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bne fail
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pulx
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cpx #0xabcd ; Stack parameter preserved
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bne fail
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ldd #_far_foo ; Get address of trampoline handler
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xgdx
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jsr 0,x
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ldd #_far_bar ; Likewise (unique trampoline check)
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xgdy
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jsr 0,y
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call _far_no_tramp ; No trampoline generated for _far_no_tramp
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clra
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clrb
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wai
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fail:
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ldd #1
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wai
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bra start
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.sect .bank1,"ax"
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.globl _far_bar
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.far _far_bar ; Must mark symbol as far
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_far_bar:
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jsr local_bank1
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xgdx
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rtc
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local_bank1:
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rts
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.sect .bank2,"ax"
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.globl _far_foo
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.far _far_foo
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_far_foo:
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jsr local_bank2
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rtc
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local_bank2:
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rts
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.sect .bank3,"ax"
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.globl _far_no_tramp
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.far _far_no_tramp
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_far_no_tramp:
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jsr local_bank3
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rtc
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local_bank3:
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rts
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.sect .text
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.globl __far_trampoline
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__far_trampoline:
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movb 0,sp, 2,sp ; Copy page register below the caller's return
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leas 2,sp ; address.
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jmp 0,y ; We have a 'call/rtc' stack layout now
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; and can jump to the far handler
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; (whose memory bank is mapped due to the
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; call to the trampoline).
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.sect .bss
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.skip 100
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stack:
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