Re: [PATCH] riscv/atomic: Do proper sign extension also for unsigned in arch_cmpxchg

Andreas Schwab
2025-02-03T08:42:57Z

On Jan 30 2025, Jessica Clarke wrote:

> On 30 Jan 2025, at 15:53, Andreas Schwab <schwab@suse.de> wrote:
>>
>> On Jan 30 2025, Alexandre Ghiti wrote:
>>
>>> a2 is used as it is passed by the calling function, so we can't be sure a2
>>> is sign extended to me, what am I missing?
>>
>> 32-bit scalar arguments are guaranteed to be sign extended on entry.
>
> Firstly, the calling convention is irrelevant if the function is
> inlined, which this almost always will be.

This is only about the non-inlined variant.

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Andreas Schwab, SUSE Labs, schwab@suse.de
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