Re: [RFC PATCH v6 10/32] x86/apic: Change apic_*_vector() vector param to unsigned

[Borislav Petkov]

On Wed, May 14, 2025 at 12:47:41PM +0530, Neeraj Upadhyay wrote:
> Change vector parameter of apic_{set|clear|test}_vector to
> unsigned int to optimize code generation for modulo operation.
> 
> On gcc-14.2, code generation for below C statement is given
> after it.
> 
> long nr = APIC_VECTOR_TO_BIT_NUMBER(vec);
> 
> * Without change:
> 
>  mov    eax,edi
>  sar    eax,0x1f
>  shr    eax,0x1b
>  add    edi,eax
>  and    edi,0x1f
>  sub    edi,eax
>  movsxd rdi,edi
>  mov    QWORD PTR [rsp-0x8],rdi
> 
> * With change:
> 
>  and    edi,0x1f
>  mov    QWORD PTR [rsp-0x8],rdi

AT&T assembly please.

This change needs to go first too.

-- 
Regards/Gruss,
    Boris.

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