Re: [PATCH 2/7] target/arm: Handle FPU being disabled in FPCXT_NS accesses

[Richard Henderson]

On 6/18/21 7:10 AM, Peter Maydell wrote:
> If the guest makes an FPCXT_NS access when the FPU is disabled,
> one of two things happens:
>   * if there is no active FP context, then the insn behaves the
>     same way as if the FPU was enabled: writes ignored, reads
>     same value as FPDSCR_NS
>   * if there is an active FP context, then we take a NOCP
>     exception
>
> Add code to the sysreg read/write functions which emits
> code to take the NOCP exception in the latter case.
>
> At the moment this will never be used, because the NOCP checks in
> m-nocp.decode happen first, and so the trans functions are never
> called when the FPU is disabled.  The code will be needed when we
> move the sysreg access insns to before the NOCP patterns in the
> following commit.
>
> Cc:qemu-stable@nongnu.org
> Signed-off-by: Peter Maydell<peter.maydell@linaro.org>
> ---

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

r~