Re: [PATCH] Account for prologue spills in reg_pressure scheduling

[Richard Sandiford]

Maxim Kuvyrkov <maxim.kuvyr...@linaro.org> writes:
> +      for (i = 0; i < FIRST_PSEUDO_REGISTER; ++i)
> +     if (call_used_regs[i])
> +       for (c = 0; c < ira_pressure_classes_num; ++c)
> +         {
> +           int j;
> +           enum reg_class cl = ira_pressure_classes[c];
> +
> +           for (j = 0; j < ira_class_hard_regs_num[cl]; ++j)
> +             if (ira_class_hard_regs[cl][j] == i)
> +               {
> +                 /* Register I belongs to pressure class CL.  Pressure
> +                    classes do not intersect, so don't look further.  */
> +                 ++call_used_regs_num[cl];
> +                 break;
> +               }
> +         }

It'd be easier to iterate over the classes as the outer loop:

    for (int c = 0; c < ira_pressure_classes_num; ++c)
      {
        enum reg_class cl = ira_pressure_classes[c];
        for (int i = 0; i < ira_class_hard_regs_num[cl]; ++i)
          if (call_used_regs[ira_class_hard_regs[cl][i]])
            ...

Thanks,
Richard