Re: [PATCH] x86: Handle vector broadcast source

[Hongtao Liu]

On Thu, Jun 26, 2025 at 1:59 PM H.J. Lu <hjl.to...@gmail.com> wrote:
>
> Use the inner scalar mode of vector broadcast source in:
>
>   (set (reg:V8DF 394)
>        (vec_duplicate:V8DF (reg:V2DF 190 [ alpha ])))
>
> to compute the vector mode for broadcast from vector source.

 ix86_get_vector_cse_mode (unsigned int size, machine_mode smode)
 {
+  /* Use the inner scalar mode of vector broadcast source in:
+
+     (set (reg:V8DF 394)
+   (vec_duplicate:V8DF (reg:V2DF 190 [ alpha ])))
+
+     to compute the vector mode for broadcast from vector source.
+   */
+  if (VECTOR_MODE_P (smode))
+    smode = GET_MODE_INNER (smode);

I think we need to figure out why vector mode is passed to
ix86_get_vector_cse_mode and fix there.
>
> gcc/
>
> PR target/120830
> * config/i386/i386-features.cc (ix86_get_vector_cse_mode): Handle
> vector broadcast source.
>
> gcc/testsuite/
>
> PR target/120830
> * g++.target/i386/pr120830.C: New test.
>
> OK for master?
>
> --
> H.J.



-- 
BR,
Hongtao