[PING][PATCH] ira: update allocated_hardreg_p[] in improve_allocation() [PR110254]

[Surya Kumari Jangala]

Ping

On 21/07/23 3:43 pm, Surya Kumari Jangala via Gcc-patches wrote:
> The improve_allocation() routine does not update the
> allocated_hardreg_p[] array after an allocno is assigned a register.
> 
> If the register chosen in improve_allocation() is one that already has
> been assigned to a conflicting allocno, then allocated_hardreg_p[]
> already has the corresponding bit set to TRUE, so nothing needs to be
> done.
> 
> But improve_allocation() can also choose a register that has not been
> assigned to a conflicting allocno, and also has not been assigned to any
> other allocno. In this case, allocated_hardreg_p[] has to be updated.
> 
> 2023-07-21  Surya Kumari Jangala  <jskumari@linux.ibm.com>
> 
> gcc/
> 	PR rtl-optimization/PR110254
> 	* ira-color.cc (improve_allocation): Update array
> ---
> 
> diff --git a/gcc/ira-color.cc b/gcc/ira-color.cc
> index 1fb2958bddd..5807d6d26f6 100644
> --- a/gcc/ira-color.cc
> +++ b/gcc/ira-color.cc
> @@ -3340,6 +3340,10 @@ improve_allocation (void)
>  	}
>        /* Assign the best chosen hard register to A.  */
>        ALLOCNO_HARD_REGNO (a) = best;
> +
> +      for (j = nregs - 1; j >= 0; j--)
> +	allocated_hardreg_p[best + j] = true;
> +
>        if (internal_flag_ira_verbose > 2 && ira_dump_file != NULL)
>  	fprintf (ira_dump_file, "Assigning %d to a%dr%d\n",
>  		 best, ALLOCNO_NUM (a), ALLOCNO_REGNO (a));