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Re: m68k call_value insn
Bernardo Innocenti <bernie@develer.com> writes:
> Andreas Schwab wrote:
>> Bernardo Innocenti <bernie@develer.com> writes:
>>
>>>Hello,
>>>
>>>it seems the call_value insn in the m68k back-end isn't
>>>really doing what its specification says:
>>>
>>>`call_value'
>>> Subroutine call instruction returning a value. Operand 0 is the
>>> hard register in which the value is returned. There are three more
>>> operands, the same as the three operands of the `call' instruction
>>> (but with numbers increased by one).
>>>
>>> Subroutines that return `BLKmode' objects use the `call' insn.
>>>
>>>
>>>The code in m68k.md seems to be ignoring operand 0, thus leaving the
>>>return value in %d0 (or %fp0 for floats), which is apparently invalid:
>> Since the register for the return value is fixed, there is no point in
>> looking at operand 0.
>
> I thought that pattern was meant to do something like this:
>
> jsr %1
> move.l %%d0,%0
I think current uses never pass anything unusual.
Andreas.
--
Andreas Schwab, SuSE Labs, schwab@suse.de
SuSE Linux AG, Deutschherrnstr. 15-19, D-90429 Nürnberg
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