Re: [RFC PATCH 10/25] target/riscv/debug: Maintain itrigger_enabled in helper_itrigger_match()

[Daniel Henrique Barboza <daniel.barboza@oss.qualcomm.com>]

On 1/14/2026 1:46 AM, Nicholas Piggin wrote:
> helper_itrigger_match() iterates over all triggers so it can maintain
> itrigger_enabled rather than calling riscv_itrigger_enabled() which
> becomes O(N^2) where N is the number of icount triggers.
> 
> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
> ---

Reviewed-by: Daniel Henrique Barboza <daniel.barboza@oss.qualcomm.com>

>   target/riscv/debug.c | 13 ++++++++++++-
>   1 file changed, 12 insertions(+), 1 deletion(-)
> 
> diff --git a/target/riscv/debug.c b/target/riscv/debug.c
> index d835c0e79a..7ae02fe2d2 100644
> --- a/target/riscv/debug.c
> +++ b/target/riscv/debug.c
> @@ -693,9 +693,18 @@ bool riscv_itrigger_enabled(CPURISCVState *env)
>       return false;
>   }
>   
> +/*
> + * This is called by TCG when an instruction completes.
> + * TCG runs in single-step mode when itrigger_enabled = true, so
> + * it can call after each insn.
> + */
>   void helper_itrigger_match(CPURISCVState *env)
>   {
>       int count;
> +    bool enabled = false;
> +
> +    g_assert(env->itrigger_enabled);
> +
>       for (int i = 0; i < RV_MAX_TRIGGERS; i++) {
>           if (get_trigger_type(env, i) != TRIGGER_TYPE_INST_CNT) {
>               continue;
> @@ -709,10 +718,12 @@ void helper_itrigger_match(CPURISCVState *env)
>           }
>           itrigger_set_count(env, i, count--);
>           if (!count) {
> -            env->itrigger_enabled = riscv_itrigger_enabled(env);
>               do_trigger_action(env, i);
> +        } else {
> +            enabled = true;
>           }
>       }
> +    env->itrigger_enabled = enabled;
>   }
>   
>   static void riscv_itrigger_update_count(CPURISCVState *env)