Re: [PATCH] gdb: LoongArch: Recognize LoongArch v1.10 store conditional instructions

[Tiezhu Yang <yangtiezhu@loongson.cn>]

On 2025/8/19 下午3:33, Xi Ruoyao wrote:
> We can't put a breakpoint in the middle of a ll/sc atomic sequence,
> recognize the sc.q, screl.w, and screl.d instructions added in LoongArch

sc.q, ll.acq.{w/d}, sc.rel.{w/d}

> v1.10 so a ll/sc atomic sequence using them won't loop forever being
> debugged.

It is better to add the references:

https://loongson.github.io/LoongArch-Documentation/LoongArch-Vol1-EN.html#_sc_q
https://loongson.github.io/LoongArch-Documentation/LoongArch-Vol1-EN.html#_ll_acq_wd_sc_rel_wd

> Signed-off-by: Xi Ruoyao <xry111@xry111.site>
> ---
>   gdb/loongarch-tdep.c | 9 +++++++--
>   1 file changed, 7 insertions(+), 2 deletions(-)
> 
> diff --git a/gdb/loongarch-tdep.c b/gdb/loongarch-tdep.c
> index cc75cd4a3d3..7556b81a9fa 100644
> --- a/gdb/loongarch-tdep.c
> +++ b/gdb/loongarch-tdep.c
> @@ -98,7 +98,9 @@ static bool
>   loongarch_insn_is_ll (insn_t insn)
>   {
>     if ((insn & 0xff000000) == 0x20000000		/* ll.w  */
> -      || (insn & 0xff000000) == 0x22000000)	/* ll.d  */
> +      || (insn & 0xff000000) == 0x22000000	/* ll.d  */
> +      || (insn & 0xfffffc00) == 0x38578000	/* llacq.w  */
> +      || (insn & 0xfffffc00) == 0x38578800)	/* llacq.d  */
>       return true;
>     return false;
>   }
> @@ -109,7 +111,10 @@ static bool
>   loongarch_insn_is_sc (insn_t insn)
>   {
>     if ((insn & 0xff000000) == 0x21000000		/* sc.w  */
> -      || (insn & 0xff000000) == 0x23000000)	/* sc.d  */
> +      || (insn & 0xff000000) == 0x23000000	/* sc.d  */
> +      || (insn & 0xffff8000) == 0x38570000	/* sc.q  */
> +      || (insn & 0xfffffc00) == 0x38578400	/* screl.w  */
> +      || (insn & 0xfffffc00) == 0x38578c00)	/* screl.d  */
>       return true;
>     return false;
>   }

The encodings for the instructions that you're handling look correct
to me. I prefer using ll.acq.w, ll.acq.d, sc.rel.w, sc.rel.d in the
code comments to make consistent with the manual.

If no more comments, I will amend these when applying in the next week,
no need to send v2.

Thanks,
Tiezhu