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