[Bug tree-optimization/89430] A missing ifcvt optimization to generate csel

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89430

--- Comment #15 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Hao Liu <hliu@gcc.gnu.org>:

https://gcc.gnu.org/g:54ecfb182bc32140722022c1d9818dee4bdc0e45

commit r11-897-g54ecfb182bc32140722022c1d9818dee4bdc0e45
Author: Hao Liu <hliu@os.amperecomputing.com>
Date:   Thu Jun 4 16:28:37 2020 +0800

    cselim: Extend to check non-trapping for more references [PR89430]

    If there is a dominating store, a store to the same reference can not be
    trapped.  But previously, it only supports such check on MEM_REFs.
    So this patch extends it to support ARRAY_REFs and COMPONENT_REFs.

    This patch also supports a special case: if there is a dominating load of
    local variable without address escape, a store is not trapped, as local
    stack is always writable.  Other loads are ignored for simplicity, as they
    don't help to check if a store can be trapped (the memory may be
read-only).

    gcc/ChangeLog:

            PR tree-optimization/89430
            * tree-ssa-phiopt.c
            (struct name_to_bb): Rename to ref_to_bb; add a new field exp;
            remove ssa_name_ver, store, offset fields.
            (struct ssa_names_hasher): Rename to refs_hasher; update functions.
            (class nontrapping_dom_walker): Rename m_seen_ssa_names to
m_seen_refs.
            (nontrapping_dom_walker::add_or_mark_expr): Extend to support
ARRAY_REFs
            and COMPONENT_REFs.

    gcc/testsuite/ChangeLog:

            PR tree-optimization/89430
            * gcc.dg/tree-ssa/pr89430-1.c: Remove xfail.
            * gcc.dg/tree-ssa/pr89430-2.c: Remove xfail.
            * gcc.dg/tree-ssa/pr89430-5.c: Remove xfail.
            * gcc.dg/tree-ssa/pr89430-6.c: Remove xfail.
            * gcc.dg/tree-ssa/pr89430-7-comp-ref.c: New test.
            * gcc.dg/tree-ssa/pr89430-8-mem-ref-size.c: New test.
            * gcc.dg/tree-ssa/ssa-pre-17.c: Add -fno-tree-cselim.