https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109154
--- Comment #7 from Richard Biener <rguenth at gcc dot gnu.org> ---
(In reply to Richard Biener from comment #6)
> ah, probably it's the missing CSE there:
>
> <bb 3> :
> _1 = (float) l_10;
> _2 = _1 < 0.0;
> zone1_17 = (int) _2;
> if (_1 < 0.0)
>
> we are not considering to replace the FP compare control if (_1 < 0.0)
> with an integer compare control if (_2 != 0). Maybe we should do that?
Just to note it's forwprop which introudces the FP control stmt:
_1 = (float) l_10;
_2 = _1 < 0.0;
zone1_17 = (int) _2;
- zone1.1_18 = zone1_17;
- if (zone1.1_18 != 0)
+ if (_1 < 0.0)
goto <bb 4>; [INV]
else
goto <bb 5>; [INV]
<bb 4> :
- iftmp.0_20 = zone1.1_18;
<bb 5> :
- # iftmp.0_11 = PHI <iftmp.0_20(4), 1(3)>
+ # iftmp.0_11 = PHI <zone1_17(4), 1(3)>
that makes the situation more difficult for VRP, I suppose that relations
should still allow us to see zone1_17(4) is 1 on the edge 3->4? For
value-numbering the situation is not easily resovable.
