Re: [PATCH] expand: Use less costly from sign and zero extensions for values where value range says they don't have MSB set [PR120434]

[Jakub Jelinek]

On Fri, Jun 06, 2025 at 10:07:54PM -0700, Andrew Pinski wrote:
> > --- gcc/expr.cc.jj      2025-06-05 10:36:06.545069723 +0200
> > +++ gcc/expr.cc 2025-06-05 19:14:45.601489036 +0200
> > @@ -9885,14 +9885,68 @@ expand_expr_real_2 (const_sepops ops, rt
> >         op0 = gen_rtx_fmt_e (TYPE_UNSIGNED (TREE_TYPE (treeop0))
> >                              ? ZERO_EXTEND : SIGN_EXTEND, mode, op0);
> >
> > +      else if (SCALAR_INT_MODE_P (GET_MODE (op0))
> > +              && optimize >= 2
> 
> Maybe flag_expensive_optimizations instead?

optimize >= 2 is used in other places doing similar things during expansion.

        Jakub