RE: [PATCH 4/4] target/hexagon: idef-parser simplify predicate init

[<ltaylorsimpson@gmail.com>]

> -----Original Message-----
> From: Anton Johansson <anjo@rev.ng>
> Sent: Monday, May 6, 2024 1:31 PM
> To: qemu-devel@nongnu.org
> Cc: ale@rev.ng; ltaylorsimpson@gmail.com; bcain@quicinc.com
> Subject: [PATCH 4/4] target/hexagon: idef-parser simplify predicate init
> 
> Only predicate instruction arguments need to be initialized by
idef-parser.
> This commit removes registers from the init_list and simplifies
> gen_inst_init_args() slightly.
> 
> Signed-off-by: Anton Johansson <anjo@rev.ng>
> ---
>  target/hexagon/idef-parser/idef-parser.y    |  2 --
>  target/hexagon/idef-parser/parser-helpers.c | 20 +++++++++-----------
>  2 files changed, 9 insertions(+), 13 deletions(-)

> diff --git a/target/hexagon/idef-parser/parser-helpers.c
> b/target/hexagon/idef-parser/parser-helpers.c
> index bae01c2bb8..33e8f82007 100644
> --- a/target/hexagon/idef-parser/parser-helpers.c
> +++ b/target/hexagon/idef-parser/parser-helpers.c
> @@ -1652,26 +1652,24 @@ void gen_inst(Context *c, GString *iname)
> 
>  void gen_inst_init_args(Context *c, YYLTYPE *locp)  {
> +    /* If init_list is NULL arguments have already been initialized */
>      if (!c->inst.init_list) {
>          return;
>      }
> 
>      for (unsigned i = 0; i < c->inst.init_list->len; i++) {
>          HexValue *val = &g_array_index(c->inst.init_list, HexValue, i);
> -        if (val->type == REGISTER_ARG) {
> -            /* Nothing to do here */
> -        } else if (val->type == PREDICATE) {
> -            char suffix = val->is_dotnew ? 'N' : 'V';
> -            EMIT_HEAD(c, "tcg_gen_movi_i%u(P%c%c, 0);\n", val->bit_width,
> -                      val->pred.id, suffix);
> -        } else {
> -            yyassert(c, locp, false, "Invalid arg type!");
> -        }
> +        yyassert(c, locp, val->type == PREDICATE,
> +                 "Only predicates need to be initialized!");
> +        char suffix = val->is_dotnew ? 'N' : 'V';

Declarations should be at the beginning of the function per QEMU coding
standards.

> +        EMIT_HEAD(c, "tcg_gen_movi_i%u(P%c%c, 0);\n", val->bit_width,

Since you know this is a predicate, the bit_width will always be 32.  You
can hard-code that instead of using %u.

> +                  val->pred.id, suffix);
>      }
> 
>      /* Free argument init list once we have initialized everything */

Taylor