Question on scalar replacement

[Richard Kenner]

    > <L10>:;
    >   #   TMT.192_94 = V_MAY_DEF <TMT.192_1>;
    >   #   TMT.193_95 = V_MAY_DEF <TMT.193_8>;
    >   #   FRAME.64_33 = V_MAY_DEF <FRAME.64_85>;
    >   FRAME.64.M12b = system__secondary_stack__ss_mark ();

    So much for that idea.  Set a breakpoint in tree-sra.c:scalarize_stmt
    and continue until you hit this statement.  Start stepping from there to
    see why we don't rewrite the LHS of that assignment.

The RHS is a call, so it calls scalarize_call_expr.  This seems to look
inside the args, but only check the RHS for is_sra_candidate_decl.  From
other code, it looks like checking is_sra_candidate_ref seems correct.