[Bug tree-optimization/103317] Spec 2017 benchmark blender_r fails with -Ofast on PowerPc (power9, power10)

[bergner at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103317

Peter Bergner <bergner at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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                 CC|                            |rguenth at gcc dot gnu.org

--- Comment #4 from Peter Bergner <bergner at gcc dot gnu.org> ---
My bisect flagged the following commit as causing the ICE:

commit f98f373dd822b35c52356b753d528924e9f89678
Commit:     Richard Biener <rguenther@suse.de>
CommitDate: Tue Nov 16 11:31:05 2021 +0100

    tree-optimization/102880 - make PHI-OPT recognize more CFGs
----
    This allows extra edges into the middle BB for the PHI-OPT
    transforms using replace_phi_edge_with_variable that do not
    end up moving stmts from that middle BB.  This avoids regressing
    gcc.dg/tree-ssa/ssa-hoist-4.c with the actual fix for PR102880
    where CFG cleanup has the choice to remove two forwarders and
    picks "the wrong" leading to