Re: [Qemu-devel] [PATCH v1 3/3] tcg-runtime: short-circuit lookup_tb_ptr on IRQs

[Peter Maydell]

On 14 June 2017 at 18:49, Alex Bennée <address@hidden> wrote:
> diff --git a/target/arm/op_helper.c b/target/arm/op_helper.c
> index 2a85666579..7e67bb3db2 100644
> --- a/target/arm/op_helper.c
> +++ b/target/arm/op_helper.c
> @@ -835,6 +835,9 @@ void HELPER(msr_i_pstate)(CPUARMState *env, uint32_t op, 
> uint32_t imm)
>          break;
>      case 0x1f: /* DAIFClear */
>          env->daif &= ~((imm << 6) & PSTATE_DAIF);
> +        /* This may result in pending IRQs being unmasked so ensure we
> +           exit the loop */
> +        cpu_exit(ENV_GET_CPU(env));
>          break;
>      default:
>          g_assert_not_reached();

The 'op' field we're switching on here is just a constant
from the instruction encoding, so I'd rather see us
identify that in translate-a64.c and end the TB or
whatever when we need to, rather than doing the
longjump-out-of-here that cpu_exit() does at runtime.

thanks
-- PMM