[Qemu-devel] Re: [PATCH 07/15] Correct ppc popcntb logic, implement popcntw and popcntd

[Alexander Graf]

On 12.02.2011, at 15:54, David Gibson wrote:

> From: David Gibson <address@hidden>
> 
> qemu already includes support for the popcntb instruction introduced
> in POWER5 (although it doesn't actually allow you to choose POWER5).
> 
> However, the logic is slightly incorrect: it will generate results
> truncated to 32-bits when the CPU is in 32-bit mode.  This is not
> normal for powerpc - generally arithmetic instructions on a 64-bit
> powerpc cpu will generate full 64 bit results, it's just that only the
> low 32 bits will be significant for condition codes.
> 
> This patch corrects this nit, which actually simplifies the code slightly.
> 
> In addition, this patch implements the popcntw and popcntd
> instructions added in POWER7, in preparation for allowing POWER7 as an
> emulated CPU.
> 
> Signed-off-by: David Gibson <address@hidden>

I trust you on the implementation details of this one. Rest looks good.

Acked-by: Alexander Graf <address@hidden>


Alex