Re: [PATCH v7 06/15] perf annotate-arm64: Support store instruction tracking

[Namhyung Kim]

On Tue, Oct 13, 2026 at 01:28:04PM +0000, Tengda Wu wrote:
> Extend update_insn_state_arm64() to handle standard store instructions
> (str, stur, stlr, stp). Exclusive stores (e.g., stxr, stxp) are omitted
> as they exhibit different operand semantics.
> 
> Unlike load instructions, a store instruction sets a value in the struct
> within the memory where the destination register resides, and does not
> alter its type. Therefore, no processing is required for the transfer.

But the target location also can be stack which requires type info,
right?  Oh, I think you have a patch later to handle that.

Thanks,
Namhyung

> 
> The only point to note is that store instructions support pre-index and
> post-index addressing modes, so calling adjust_reg_index_state() is still
> necessary to handle their addressing.
> 
> Reviewed-by: Ian Rogers <irogers@xxxxxxxxxx>
> Signed-off-by: Tengda Wu <wutengda@xxxxxxxxxxxxxxx>
> ---
>  .../perf/util/annotate-arch/annotate-arm64.c  | 25 +++++++++++++++++++
>  1 file changed, 25 insertions(+)
> 
> diff --git a/tools/perf/util/annotate-arch/annotate-arm64.c b/tools/perf/util/annotate-arch/annotate-arm64.c
> index fb48bf95b32f..54d9928b536f 100644
> --- a/tools/perf/util/annotate-arch/annotate-arm64.c
> +++ b/tools/perf/util/annotate-arch/annotate-arm64.c
> @@ -661,6 +661,20 @@ static void update_load_insn_state(struct type_state *state,
>  	adjust_reg_index_state(state, dloc, dl, src);
>  }
>  
> +/*
> + * Match standard store variants (str, stur, stlr, stp) that follow
> + * straightforward store semantics: source registers on the left (read-only)
> + * and memory target on the right. Excludes exclusive stores (stxr, stxp, etc.)
> + * which have status/result register side effects.
> + */
> +static bool is_standard_store_insn(const char *name)
> +{
> +	return !strncmp(name, "str", 3)  ||  /* str, strb, strh */
> +	       !strncmp(name, "stur", 4) ||  /* stur, sturb, sturh */
> +	       !strncmp(name, "stlr", 4) ||  /* stlr, stlrb, stlrh */
> +	       !strncmp(name, "stp", 3);     /* stp */
> +}
> +
>  static void update_insn_state_arm64(struct type_state *state,
>  				    struct data_loc_info *dloc, Dwarf_Die *cu_die,
>  				    struct disasm_line *dl)
> @@ -742,6 +756,17 @@ static void update_insn_state_arm64(struct type_state *state,
>  	/* Memory to register transfers */
>  	if (is_standard_load_insn(dl->ins.name))
>  		update_load_insn_state(state, dloc, dl, src, dst);
> +	/* Register to memory transfers */
> +	else if (is_standard_store_insn(dl->ins.name)) {
> +		/*
> +		 * Ignore transfers since it'd set a value in a struct
> +		 * and won't change the type.
> +		 *
> +		 * Needs to update the pre-index and post-index addressing
> +		 * modes for the destination register.
> +		 */
> +		adjust_reg_index_state(state, dloc, dl, dst);
> +	}
>  }
>  #endif
>  
> -- 
> 2.34.1
>