Re: [Qemu-devel] [RFC PATCH 4/6] target/ppc: switch FPR, VMX and VSX helpers to access data directly from cpu_env

[Richard Henderson <richard.henderson@linaro.org>]

On 12/7/18 2:56 AM, Mark Cave-Ayland wrote:
> Instead of accessing the FPR, VMX and VSX registers through static arrays of
> TCGv_i64 globals, remove them and change the helpers to load/store data directly
> within cpu_env.
> 
> Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
> ---
>  target/ppc/translate.c | 59 ++++++++++++++------------------------------------
>  1 file changed, 16 insertions(+), 43 deletions(-)

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

Note however, that there are other steps that you must add here before using
vector operations in the next patch:

(1a) The fpr and vsr arrays must be merged, since fpr[n] == vsrh[n].
     If this isn't done, then you simply cannot apply one operation
     to two disjoint memory blocks.

(1b) The vsr and avr arrays should be merged, since vsr[32+n] == avr[n].
     This is simply tidiness, matching the layout to the architecture.

These steps will modify gdbstub.c, machine.c, and linux-user/.

(2) The vsr array needs to be QEMU_ALIGN(16).  See target/arm/cpu.h.
    We assert that the host addresses are 16 byte aligned, so that we
    can eventually use Altivec/VSX in tcg/ppc/.


r~