[Bug tree-optimization/112843] during GIMPLE pass: bitintlower ICE: SIGSEGV in ranger_cache::range_of_expr (gimple-range-cache.cc:1204) with _BitInt() at -O1

["amacleod at redhat dot com" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112843

--- Comment #9 from Andrew Macleod <amacleod at redhat dot com> ---
Created attachment 56790
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=56790&action=edit
auxially patch to avid the trap

refining a range is fine...  the only issue we are really running into here
that is causing the trap is that the "update" on the original LHS DEF is a new
stmt which hasnt been added to the IL yet, so ranger is trapping when it asks
for the basic block of the def stmt.. It had one before, it expects it to still
have one when it looks at the context of the stmt to update the range.

Now that said, the update issue is primarily within the cache.  if we are
updating and the BB isn't set, we could simply just pick up the global value. 
Patch is attached, and pre-approved if you want to use it.