[Bug time/19363] x32: times() return value wrongly truncates/sign extends from 32bit

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

https://sourceware.org/bugzilla/show_bug.cgi?id=19363

--- Comment #12 from cvs-commit at gcc dot gnu.org <cvs-commit at gcc dot gnu.org> ---
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The branch, hjl/pr19363/2.22 has been created
        at  7c1c303f4ffa7eafe704c13d4f4549f007e3075d (commit)

- Log -----------------------------------------------------------------
https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=7c1c303f4ffa7eafe704c13d4f4549f007e3075d

commit 7c1c303f4ffa7eafe704c13d4f4549f007e3075d
Author: H.J. Lu <hjl.tools@gmail.com>
Date:   Thu Dec 17 11:46:49 2015 -0800

    Provide x32 times

    Since times returns 64-bit clock_t on x32, we need to provide x32 times
    by redefining INTERNAL_SYSCALL_NCS and INTERNAL_SYSCALL_ERROR_P with
    64-bit return type for syscall.  All system calls returning 64-bit
    integer, which are lseek, time and times, must be handled specially for
    x32.  lseek is handled by x32 lseek.S and time doesn't check syscall
    return.  times is the only missed one.  Before this patch, there are

    0000000 <__times>:
       0:       b8 64 00 00 40          mov    $0x40000064,%eax
       5:       0f 05                   syscall
       7:       48 63 d0                movslq %eax,%rdx
                                    ^^^^^^^^^^ Incorrect signed extension
       a:       48 83 fa f2             cmp    $0xfffffffffffffff2,%rdx
       e:       75 07                   jne    17 <__times+0x17>
      10:       3d 00 f0 ff ff          cmp    $0xfffff000,%eax
                                    ^^^^^^^^^^^^^^^^^^^^^ 32-bit compare
      15:       77 11                   ja     28 <__times+0x28>
      17:       48 83 fa ff             cmp    $0xffffffffffffffff,%rdx
      1b:       b8 00 00 00 00          mov    $0x0,%eax
      20:       48 0f 45 c2             cmovne %rdx,%rax
      24:       c3                      retq

    After this patch, there are

    00000000 <__times>:
       0:       b8 64 00 00 40          mov    $0x40000064,%eax
       5:       0f 05                   syscall
       7:       48 83 f8 f2             cmp    $0xfffffffffffffff2,%rax
       b:       75 08                   jne    15 <__times+0x15>
       d:       48 3d 00 f0 ff ff       cmp    $0xfffffffffffff000,%rax
      13:       77 13                   ja     28 <__times+0x28>
      15:       48 83 f8 ff             cmp    $0xffffffffffffffff,%rax
      19:       ba 00 00 00 00          mov    $0x0,%edx
      1e:       48 0f 44 c2             cmove  %rdx,%rax
      22:       c3                      retq

    The incorrect signed extension and 32-bit compare are gone.

        [BZ #19363]
        * sysdeps/unix/sysv/linux/x86_64/x32/times.c: New file.

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