pack has the minimal alignment, which is 1 byte.
在 2011年8月25日 下午4:20，Sun Chan <sun.c...@gmail.com>写道：
> you can think of pack is really a special case of no alignment
> Sun
>
> 2011/8/25 Sun Chan <sun.c...@gmail.com>:
> > it's not a question. I am saying, symbol of different alignment should
> > have different type. Hence, the alignment is associated at type table,
> > not symtab
> > Sim
> >
> > 2011/8/25 Jian-Xin Lai <laij...@gmail.com>:
> >> I'm not sure if I understand your question. The TY_IDX is composed by 2
> >> parts: index to TY_TABLE and extra flags for volatile, restrict and
> >> alignment. Every symbol with the same TY has its own alignment embeded
> in
> >> the TY_IDX.
> >>
> >> 在 2011年8月25日 下午4:01，Sun Chan <sun.c...@gmail.com>写道：
> >>>
> >>> I have problem having one attribute that have annotation in 2
> >>> different places. Also, the reason it is in TYPE is that symbols of
> >>> the same declaration but of different alignment should really be of
> >>> different type.
> >>> Sun
> >>>
> >>> 2011/8/25 Jian-Xin Lai <laij...@gmail.com>:
> >>> > The TY has "packed" flag and it's detected in Adjust_Alignment:
> >>> > 125 align= TY_align(ty_idx);
> >>> > 126
> >>> > 127 if (Is_Structure_Type(ty) && TY_is_packed(ty))
> >>> > 128 {
> >>> > 129 return align;
> >>> > 130 }
> >>> >
> >>> > If the TY is packed, the BE don't change its alignment. We did the
> >>> > similar
> >>> > thing. The different is our change is applied on ST instead of TY
> >>> > because
> >>> > this is a GNU extension on variable.
> >>> >
> >>> > 在 2011年8月25日 下午3:05，Sun Chan <sun.c...@gmail.com>写道：
> >>> >>
> >>> >> How would you classify "pack" data?
> >>> >> Sun
> >>> >>
> >>> >> 2011/8/25 Jian-Xin Lai <laij...@gmail.com>:
> >>> >> > The reason we introduce the "user align" is to separate this kind
> of
> >>> >> > case
> >>> >> > from the generic aggregate. So that we can do the two things well:
> >>> >> > If user specifies an alignment, we follow the size. Otherwise, the
> >>> >> > compiler
> >>> >> > can decide what's the proper alignment.
> >>> >> >
> >>> >> > 在 2011年8月25日 下午1:57，Mike Murphy <mmur...@nvidia.com>写道：
> >>> >> >>
> >>> >> >> So Aggregate_Alignment is a settable option (defaults to 16 in
> some
> >>> >> >> targets). What if you compile with -TENV:align_aggregates=8, or
> >>> >> >> don't
> >>> >> >> default it to 16?
> >>> >> >>
> >>> >> >> -----Original Message-----
> >>> >> >> From: 朱庆 [mailto:zqing1...@gmail.com]
> >>> >> >> Sent: Wednesday, August 24, 2011 10:53 PM
> >>> >> >> To: Mike Murphy
> >>> >> >> Cc: Sun Chan; open64-devel@lists.sourceforge.net
> >>> >> >> Subject: Re: [Open64-devel] Code Review request for bug832[wgen]
> >>> >> >>
> >>> >> >> The alignment is correct in .B file, but in Adjusted_Alignment
> there
> >>> >> >> are following code to modify the align. In our case we do not
> want
> >>> >> >> this happen.
> >>> >> >> else {
> >>> >> >> align = MAX(align, Aggregate_Alignment);
> >>> >> >> }
> >>> >> >>
> >>> >> >> Best wishes
> >>> >> >> zhuqing
> >>> >> >> 在 2011年8月25日 下午12:28，Mike Murphy <mmur...@nvidia.com> 写道：
> >>> >> >> > The alignment is stored in the ty_idx (see TY_align), and then
> >>> >> >> > there
> >>> >> >> > are
> >>> >> >> > routines like Adjusted_Alignment in stblock that can modify it.
> I
> >>> >> >> > suspect
> >>> >> >> > the problem here is that the alignment is being put on the
> object
> >>> >> >> > rather
> >>> >> >> > than the type, and then is lost (but should still be possible,
> >>> >> >> > because the
> >>> >> >> > TY_align is like qualifiers that can vary from the base type).
> >>> >> >> > Does
> >>> >> >> > the
> >>> >> >> > alignment show up properly in the intermediate .B file?
> >>> >> >> >
> >>> >> >> > -----Original Message-----
> >>> >> >> > From: Sun Chan [mailto:sun.c...@gmail.com]
> >>> >> >> > Sent: Wednesday, August 24, 2011 7:51 PM
> >>> >> >> > To: 朱庆
> >>> >> >> > Cc: open64-devel@lists.sourceforge.net
> >>> >> >> > Subject: Re: [Open64-devel] Code Review request for
> bug832[wgen]
> >>> >> >> >
> >>> >> >> > The reason I asked for the file is that I think there has to be
> >>> >> >> > some
> >>> >> >> > alignment attribute somewhere. I am sure data alignment has
> been
> >>> >> >> > dealt
> >>> >> >> > with in the compiler. That it is due to user, or just language
> >>> >> >> > attribute might be irrelevant from compiler point of view.
> >>> >> >> >
> >>> >> >> > Mike or Murthy,
> >>> >> >> > Do you remember where alignment is handled? I only found
> Alignment
> >>> >> >> > field in BLK of the symtab_defs.h
> >>> >> >> >
> >>> >> >> > Sun
> >>> >> >> >
> >>> >> >> > 2011/8/25 朱庆 <zqing1...@gmail.com>:
> >>> >> >> >> Hi Sun,
> >>> >> >> >>
> >>> >> >> >> Attached symtab_defs.h.
> >>> >> >> >>
> >>> >> >> >> Thanks
> >>> >> >> >> zhuqing
> >>> >> >> >> 2011/8/24 Sun Chan <sun.c...@gmail.com>:
> >>> >> >> >>> can you send me the full symtab_defs.h?
> >>> >> >> >>> Sun
> >>> >> >> >>>
> >>> >> >> >>> On Wed, Aug 24, 2011 at 4:56 PM, 朱庆 <zqing1...@gmail.com>
> wrote:
> >>> >> >> >>>> Hi all,
> >>> >> >> >>>>
> >>> >> >> >>>> Can gatekeeper help review following fix for bug832?
> >>> >> >> >>>> https://bugs.open64.net/show_bug.cgi?id=832
> >>> >> >> >>>>
> >>> >> >> >>>> small case, a.c:
> >>> >> >> >>>> struct obs_kernel_param {
> >>> >> >> >>>> const char *str;
> >>> >> >> >>>> };
> >>> >> >> >>>>
> >>> >> >> >>>> const char str1[] = "acpi_parse_apic_instance=";
> >>> >> >> >>>> const char str2[] = "acpi_os_name";
> >>> >> >> >>>> struct obs_kernel_param var1
> >>> >> >> >>>> __attribute__ ((aligned ((sizeof (long))))) =
> >>> >> >> >>>> {str1};
> >>> >> >> >>>>
> >>> >> >> >>>> struct obs_kernel_param var2
> >>> >> >> >>>> __attribute__ ((aligned ((sizeof (long))))) =
> >>> >> >> >>>> {str2};
> >>> >> >> >>>>
> >>> >> >> >>>> when compile with opencc, nm a.o
> >>> >> >> >>>> 0000000000000000 D var1
> >>> >> >> >>>> 0000000000000010 D var2
> >>> >> >> >>>> compile with gcc, nm a.o
> >>> >> >> >>>> 0000000000000000 D var1
> >>> >> >> >>>> 0000000000000008 D var2
> >>> >> >> >>>> the offset of var1 and var2 are different, the problem with
> >>> >> >> >>>> opencc
> >>> >> >> >>>> is
> >>> >> >> >>>> :fixed align attribute does not work, this may cause some
> >>> >> >> >>>> problems
> >>> >> >> >>>> when mix link two files with opencc and gcc.
> >>> >> >> >>>>
> >>> >> >> >>>> The fix is to add a new ST flag to record
> user_defined_align.
> >>> >> >> >>>>
> >>> >> >> >>>> Thanks
> >>> >> >> >>>> zhuqing
> >>> >> >> >>>>
> >>> >> >> >>>>
> >>> >> >> >>>>
> >>> >> >> >>>>
> >>> >> >> >>>>
> ------------------------------------------------------------------------------
> >>> >> >> >>>> EMC VNX: the world's simplest storage, starting under $10K
> >>> >> >> >>>> The only unified storage solution that offers unified
> >>> >> >> >>>> management
> >>> >> >> >>>> Up to 160% more powerful than alternatives and 25% more
> >>> >> >> >>>> efficient.
> >>> >> >> >>>> Guaranteed. http://p.sf.net/sfu/emc-vnx-dev2dev
> >>> >> >> >>>> _______________________________________________
> >>> >> >> >>>> Open64-devel mailing list
> >>> >> >> >>>> Open64-devel@lists.sourceforge.net
> >>> >> >> >>>> https://lists.sourceforge.net/lists/listinfo/open64-devel
> >>> >> >> >>>>
> >>> >> >> >>>>
> >>> >> >> >>>
> >>> >> >> >>
> >>> >> >> >
> >>> >> >> >
> >>> >> >> >
> >>> >> >> >
> >>> >> >> >
> ------------------------------------------------------------------------------
> >>> >> >> > EMC VNX: the world's simplest storage, starting under $10K
> >>> >> >> > The only unified storage solution that offers unified
> management
> >>> >> >> > Up to 160% more powerful than alternatives and 25% more
> efficient.
> >>> >> >> > Guaranteed. http://p.sf.net/sfu/emc-vnx-dev2dev
> >>> >> >> > _______________________________________________
> >>> >> >> > Open64-devel mailing list
> >>> >> >> > Open64-devel@lists.sourceforge.net
> >>> >> >> > https://lists.sourceforge.net/lists/listinfo/open64-devel
> >>> >> >> >
> >>> >> >> >
> >>> >> >> >
> >>> >> >> >
> >>> >> >> >
> -----------------------------------------------------------------------------------
> >>> >> >> > This email message is for the sole use of the intended
> >>> >> >> > recipient(s)
> >>> >> >> > and
> >>> >> >> > may contain
> >>> >> >> > confidential information. Any unauthorized review, use,
> >>> >> >> > disclosure
> >>> >> >> > or
> >>> >> >> > distribution
> >>> >> >> > is prohibited. If you are not the intended recipient, please
> >>> >> >> > contact
> >>> >> >> > the sender by
> >>> >> >> > reply email and destroy all copies of the original message.
> >>> >> >> >
> >>> >> >> >
> >>> >> >> >
> >>> >> >> >
> -----------------------------------------------------------------------------------
> >>> >> >> >
> >>> >> >>
> >>> >> >>
> >>> >> >>
> >>> >> >>
> ------------------------------------------------------------------------------
> >>> >> >> EMC VNX: the world's simplest storage, starting under $10K
> >>> >> >> The only unified storage solution that offers unified management
> >>> >> >> Up to 160% more powerful than alternatives and 25% more
> efficient.
> >>> >> >> Guaranteed. http://p.sf.net/sfu/emc-vnx-dev2dev
> >>> >> >> _______________________________________________
> >>> >> >> Open64-devel mailing list
> >>> >> >> Open64-devel@lists.sourceforge.net
> >>> >> >> https://lists.sourceforge.net/lists/listinfo/open64-devel
> >>> >> >
> >>> >> >
> >>> >> >
> >>> >> > --
> >>> >> > Regards,
> >>> >> > Lai Jian-Xin
> >>> >> >
> >>> >> >
> >>> >> >
> >>> >> >
> ------------------------------------------------------------------------------
> >>> >> > EMC VNX: the world's simplest storage, starting under $10K
> >>> >> > The only unified storage solution that offers unified management
> >>> >> > Up to 160% more powerful than alternatives and 25% more efficient.
> >>> >> > Guaranteed. http://p.sf.net/sfu/emc-vnx-dev2dev
> >>> >> > _______________________________________________
> >>> >> > Open64-devel mailing list
> >>> >> > Open64-devel@lists.sourceforge.net
> >>> >> > https://lists.sourceforge.net/lists/listinfo/open64-devel
> >>> >> >
> >>> >> >
> >>> >
> >>> >
> >>> >
> >>> > --
> >>> > Regards,
> >>> > Lai Jian-Xin
> >>> >
> >>
> >>
> >>
> >> --
> >> Regards,
> >> Lai Jian-Xin
> >>
> >
>
--
Regards,
Lai Jian-Xin
------------------------------------------------------------------------------
EMC VNX: the world's simplest storage, starting under $10K
The only unified storage solution that offers unified management
Up to 160% more powerful than alternatives and 25% more efficient.
Guaranteed. http://p.sf.net/sfu/emc-vnx-dev2dev
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