[Bug c++/58192] G++ emits incorrect code when passing enum classes as function parameters

["ubizjak at gmail dot com" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58192

--- Comment #9 from Uroš Bizjak <ubizjak at gmail dot com> ---
Looking at dumps, obtained with -m32 -O1, we have following sequence before the
call to _ZN2S1Ut_3setE3Foo:

_.dfinit:

(insn 7 3 8 2 (parallel [
            (set (reg:SI 88)
                (lshiftrt:SI (reg/v:SI 86 [ t ])
                    (const_int 16 [0x10])))
            (clobber (reg:CC 17 flags))
        ]) 539 {*lshrsi3_1}
     (nil))
(insn 8 7 9 2 (parallel [
            (set (reg:QI 85 [ t$2 ])
                (and:QI (subreg:QI (reg:SI 88) 0)
                    (const_int -1 [0xffffffffffffffff])))
            (clobber (reg:CC 17 flags))
        ]) 379 {*andqi_1}
     (nil))

...

(insn 10 9 11 2 (set (reg:QI 1 dx)
        (reg:QI 85 [ t$2 ])) gcc-bug.cc:72 93 {*movqi_internal}
     (nil))

...

(call_insn 12 11 13 2 (call (mem:QI (symbol_ref:SI ("_ZN2S1Ut_3setE3Foo")
[flags 0x3]  <function_decl 0x2ad94c491438 set>) [0 set S1 A8])
        (const_int 0 [0])) gcc-bug.cc:72 651 {*call}
     (expr_list:REG_EH_REGION (const_int 0 [0])
        (nil))
    (expr_list:SI (use (reg:SI 0 ax))
        (expr_list:QI (use (reg:QI 1 dx))
            (nil))))

_.cse1 mangles argument setup to:

(insn 8 7 9 2 (set (reg:QI 85 [ t$2 ])
        (subreg:QI (reg:SI 88) 0)) 93 {*movqi_internal}
     (expr_list:REG_DEAD (reg:SI 88)
        (expr_list:REG_UNUSED (reg:CC 17 flags)
            (nil))))

...

(insn 10 9 11 2 (set (reg:QI 1 dx)
        (subreg:QI (reg:SI 88) 0)) gcc-bug.cc:72 93 {*movqi_internal}
     (nil))

and _.fwprop1 merges both to:

(insn 10 9 11 2 (set (reg:QI 1 dx)
        (subreg:QI (reg:SI 88) 0)) gcc-bug.cc:72 93 {*movqi_internal}
     (nil))

resulting in:

#(insn 10 9 34 2 (set (reg:QI 1 dx)
#        (reg:QI 3 bx [88])) gcc-bug.cc:72 93 {*movqi_internal}
#     (nil))
    movl    %ebx, %edx    # 10    *movqi_internal/1    [length = 2]

However, x86 ABI mandates that arguments should be properly extended in the
call to the function. I don't think original (insn 8) is correct, as it is
effectively a NOP.
>From gcc-bugs-return-462096-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org Fri Sep 19 13:11:17 2014
Return-Path: <gcc-bugs-return-462096-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org>
Delivered-To: listarch-gcc-bugs@gcc.gnu.org
Received: (qmail 2073 invoked by alias); 19 Sep 2014 13:11:16 -0000
Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm
Precedence: bulk
List-Id: <gcc-bugs.gcc.gnu.org>
List-Archive: <http://gcc.gnu.org/ml/gcc-bugs/>
List-Post: <mailto:gcc-bugs@gcc.gnu.org>
List-Help: <mailto:gcc-bugs-help@gcc.gnu.org>
Sender: gcc-bugs-owner@gcc.gnu.org
Delivered-To: mailing list gcc-bugs@gcc.gnu.org
Received: (qmail 2050 invoked by uid 48); 19 Sep 2014 13:11:10 -0000
From: "marcos.diaz at tallertechnologies dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/63301] inconsistency on wchar_t and wint_t types and sizes for diverse architectures
Date: Fri, 19 Sep 2014 13:11:00 -0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: c
X-Bugzilla-Version: 4.8.3
X-Bugzilla-Keywords:
X-Bugzilla-Severity: normal
X-Bugzilla-Who: marcos.diaz at tallertechnologies dot com
X-Bugzilla-Status: RESOLVED
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org
X-Bugzilla-Target-Milestone: ---
X-Bugzilla-Flags:
X-Bugzilla-Changed-Fields:
Message-ID: <bug-63301-4-9fWWlDk79k@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-63301-4@http.gcc.gnu.org/bugzilla/>
References: <bug-63301-4@http.gcc.gnu.org/bugzilla/>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: 7bit
X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/
Auto-Submitted: auto-generated
MIME-Version: 1.0
X-SW-Source: 2014-09/txt/msg01930.txt.bz2
Content-length: 294

https://gcc.gnu.org/bugzilla/show_bug.cgi?idc301

--- Comment #2 from Marcos Diaz <marcos.diaz at tallertechnologies dot com> ---
Sorry, I expressed wrong the issue I was reporting, What I want to ask is the
following:

Is it ok that the wchar_t is a long int and the wint_t is just an int?