[Bug middle-end/65048] [5 Regression] ICE in add_phi_args_after_copy_edge, at tree-cfg.c

[spop at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65048

--- Comment #2 from Sebastian Pop <spop at gcc dot gnu.org> ---
Created attachment 34750
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=34750&action=edit
fix

We used to attempt to jump thread this path that is not connex:
FSM jump thread: (7, 10) (13, 14)

This is because we collect all the jump thread paths before doing code
generation, and so once we start code generating the jump threads, the CFG
changes.
The attached patch checks for valid jump threads before code generating them.

I'm testing the patch and if it passes bootstrap I will send it to gcc-patches
with an apropriate changelog.