Re: [PATCH-for-10.1 07/12] tcg: Check TARGET_INSN_START_EXTRA_WORDS range at runtime

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

On 3/19/25 06:45, Philippe Mathieu-Daudé wrote:
> Define TARGET_INSN_START_WORDS_MAX and use it to check
> TARGET_INSN_START_EXTRA_WORDS at runtime in tb_gen_code().
> 
> Suggested-by: Peter Maydell <peter.maydell@linaro.org>
> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> ---
>   include/tcg/tcg-op.h      | 4 +---
>   include/tcg/tcg.h         | 2 ++
>   accel/tcg/translate-all.c | 2 ++
>   3 files changed, 5 insertions(+), 3 deletions(-)

Nack.

> @@ -52,8 +52,6 @@ static inline void tcg_gen_insn_start(uint64_t pc, uint64_t a1, uint64_t a2)
>       tcg_set_insn_start_param(op, 1, a1);
>       tcg_set_insn_start_param(op, 2, a2);
>   }
> -#else
> -#error Unhandled TARGET_INSN_START_EXTRA_WORDS value
>   #endif

This is far superior to ...

> @@ -351,6 +352,7 @@ TranslationBlock *tb_gen_code(CPUState *cpu,
>       tcg_ctx->tlb_dyn_max_bits = CPU_TLB_DYN_MAX_BITS;
>   #endif
>       tcg_ctx->insn_start_words = TARGET_INSN_START_WORDS;
> +    tcg_debug_assert(tcg_ctx->insn_start_words <= TARGET_INSN_START_WORDS_MAX);

... this.


r~