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# MACRO: start
# All assembler tests should start with a call to "start"
.macro start
.text
# Skip over these inlined funcs.
jmp __start;
.global __pass
.type __pass, function
__pass:
# Note - we cannot just invoke:
#
# write 1, _passmsg, 5
#
# here because _passmsg contains the run-time (VMA) address of
# the pass string (probably 0x500) not the load-time (LMA)
# address (probably 0x804c). Normally using the VMA address
# would be the correct thing to do - *if* there was some start
# up code which copied data from LMA to VMA. But we have no
# start up code, so the data still resides at the LMA
# address. Hence we use __romdatastart instead.
#
# Note - we are cheating because the address that we pass to
# "write" should actually be:
#
# __romdatastart + (_passmsg - __datastart)
#
# but the assembler cannot cope with this expression. So we
# cheat and use the fact that we know that _passmsg is the
# first string in the .data section and so (_passmsg -
# __datastart) evaluates to zero.
write 1, __romdatastart, 5
exit 0
.global __fail
.type __fail, function
__fail:
# Note - see above.
#
# write 1, _failmsg, 5
#
# This time we use the fact that _passmsg is aligned to a
# 16 byte boundary to work out that (_failmsg - __datastart)
# evaluates to 0x10.
write 1, __romdatastart + 0x10, 5
exit 1
.data
_passmsg:
.ascii "pass\n"
.align 4
_failmsg:
.ascii "fail\n"
.align 4
.text
.global __start
.type __start, function
__start:
.endm
# MACRO: system_call
# Make a libgloss/Linux system call
.macro system_call nr:req
call #(0x180|\nr);
.endm
# MACRO: exit
# Quit the current test
.macro exit rc:req
mov #\rc, r12
system_call 1
.endm
# MACRO: pass
# Write 'pass' to stdout via syscalls and quit;
# meant for non-OS operating environments
.macro pass
jmp __pass;
.endm
# MACRO: fail
# Write 'fail' to stdout via syscalls and quit;
# meant for non-OS operating environments
.macro fail
jmp __fail;
.endm
# MACRO: write
# Just like the write() C function; uses system calls
.macro write fd:req, buf:req, count:req
mov #\fd, r12;
mov #\buf, r13;
mov #\count, r14;
system_call 5
.endm
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