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Re: [Qemu-devel] [RFC PATCH 1/6] target/ppc: introduce get_fpr() and set
Re: [Qemu-devel] [RFC PATCH 1/6] target/ppc: introduce get_fpr() and set_fpr() helpers for FP register access
Tue, 11 Dec 2018 19:06:20 +0000
Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.3.0
On 10/12/2018 05:17, David Gibson wrote:
> On Fri, Dec 07, 2018 at 08:56:30AM +0000, Mark Cave-Ayland wrote:
>> These helpers allow us to move FP register values to/from the specified
>> To prevent FP helpers accessing the cpu_fpr array directly, add extra TCG
>> temporaries as required.
> It's not obvious to me why that's a desirable thing. I'm assuming
> it's somehow necessary for the stuff later in the series, but I think
> we need a brief rationale here to explain why this isn't just adding
> extra reg copies for the sake of it.
Ah okay. It's because the VSX registers extend the set of VMX and FPR registers
the cpu_vsrh() and cpu_vsrl() helpers at the top of
target/ppc/translate/vsx-impl.inc.c). So in order to remove the static TCGv_i64
arrays then these helpers must also be converted.
[Qemu-devel] [RFC PATCH 6/6] target/ppc: convert vaddu[b, h, w, d] and vsubu[b, h, w, d] over to use vector operations, Mark Cave-Ayland, 2018/12/07