[Bug target/89355] Unnecessary ENDBR

["cvs-commit at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89355

--- Comment #10 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-8 branch has been updated by H.J. Lu <hjl@gcc.gnu.org>:

https://gcc.gnu.org/g:99ddb11c0840f68466a14fd583dd4d3a558d4961

commit r8-10186-g99ddb11c0840f68466a14fd583dd4d3a558d4961
Author: H.J. Lu <hjl.tools@gmail.com>
Date:   Fri Apr 17 15:23:27 2020 -0700

    x86: Insert ENDBR if function will be called indirectly

    Since constant_call_address_operand has

    ;; Test for a pc-relative call operand
    (define_predicate "constant_call_address_operand"
      (match_code "symbol_ref")
    {
      if (ix86_cmodel == CM_LARGE || ix86_cmodel == CM_LARGE_PIC
          || flag_force_indirect_call)
        return false;
      if (TARGET_DLLIMPORT_DECL_ATTRIBUTES && SYMBOL_REF_DLLIMPORT_P (op))
        return false;
      return true;
    })

    even if cgraph_node::get (cfun->decl)->only_called_directly_p () returns
    false, the fuction may still be called indirectly.  Copy the logic from
    constant_call_address_operand to rest_of_insert_endbranch to insert ENDBR
    at function entry if function will be called indirectly.

    NB: gcc.target/i386/pr94417-2.c is updated to expect 4 ENDBRs, instead
    of 2, since only GCC 10 has the fix for PR target/89355 not to insert
    ENDBR after NOTE_INSN_DELETED_LABEL.

    gcc/

            Backport from master
            PR target/94417
            * config/i386/i386.c (rest_of_insert_endbranch): Insert ENDBR at
            function entry if function will be called indirectly.

    gcc/testsuite/

            Backport from master
            PR target/94417
            * gcc.target/i386/pr94417-1.c: New test.
            * gcc.target/i386/pr94417-2.c: Likewise.
            * gcc.target/i386/pr94417-3.c: Likewise.

    (cherry picked from commit c5f379653964a1d2c7037b2de3e947a48370a198)