17 lines
451 B
ArmAsm
17 lines
451 B
ArmAsm
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; Trap 0 handler (syscall interface).
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;
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; The trap handler returns the result in r0 and the error code (errno value)
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; in r2. r1 is reserved in case an 8 byte quantity ever needs to be
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; returned in registers.
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.text
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.global __trap0
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__trap0:
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trap #0 ; trap 0 returns result in r0, error code in r2
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cmpui r2,#1 ; is error code zero?
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bc .Lret ; yes, skip setting errno
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ld r4,@(sp) ; no, set errno
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st r2,@r4
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.Lret:
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jmp lr ; return to caller
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