On Mon, Sep 20, 2021 at 10:18:15PM -0600, Jeff Law wrote: > On 9/20/2021 6:23 PM, Segher Boessenkool wrote: > >There is no such thing as "earlier than simplify-rtx", that is the > >point. simplify-rtx is not a pass: it is like a library that is used > >from all over the RTL routines. > I'm referring to earlier in the call chain, not an earlier pass. Sorry I > wasn't clear about that.
Ah okay, I see. > If we were catching the scenario which led to the creation of (subreg > (truncate)) in combine and instead of creating (subreg (truncate)) we > instead created the simplified, correct form would that ease your concerns? Yes please. And combine has access to the original instructions, so can make sure to only ever create something with the same semantics. Thanks, Segher
