https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114151
--- Comment #10 from Richard Biener <rguenth at gcc dot gnu.org> --- (In reply to Andrew Macleod from comment #9) > Created attachment 57620 [details] > proposed patch > > Does this solve your problem if there is an active ranger? it bootstraps > with no regressions I'll check what it does. > ITs pretty minimal, and basically we invokes the cache's version of > range_of_expr if there is no context. I tweaked it such that if there is > no context, and the def has not been calculated yet, it calls range_of_def, > and combines it with any SSA_NAME_RANGE_INFO that may have pre-existed. All > without invoking any new lookups. > > This seems relatively harmless and does not spawn new dynamic lookups. As > long as it resolves your issue... If it still does not work, and we > require the def to actually be evaluated, I will look into that. we prpbably > should do that anyway. There appears to be a cycle when this is invoked > from the loop analysis, probably because folding of PHIs uses loop info... > and back and forth we go. Yeah, I ran into this as well. > I'd probably need to add a flag to the ranger > instantiation to tell it to avoid using loop info. I've quickly tried to detect active discovery in SCEV but it wasn't as easy as I thought. > Are we looking to fix this in this release? I think the full evaluation has to wait for stage1 because of that recursion issue. I'm also sure we're going to need ways to _not_ do this, so maybe a clearer separation in the API is warranted. As I see it when you call range_of_expr without context you get the same result as if using the global range query so maybe it should be a different API from the start (the one that is now without context) and range_of_expr without context using a conservative default (the definition point).
