This is the mail archive of the
gcc@gcc.gnu.org
mailing list for the GCC project.
Re: Tree sharing issues...
- From: law at redhat dot com
- To: Jan Hubicka <jh at suse dot cz>
- Cc: Jan Hubicka <hubicka at ucw dot cz>, Richard Henderson <rth at redhat dot com>, gcc at gcc dot gnu dot org
- Date: Wed, 19 Nov 2003 15:16:25 -0700
- Subject: Re: Tree sharing issues...
- Reply-to: law at redhat dot com
In message <20031119221355.GN11681@kam.mff.cuni.cz>, Jan Hubicka writes:
>> > On Wed, Nov 19, 2003 at 08:01:52PM +0100, Jan Hubicka wrote:
>> > > I am almost done with verify_stmts except for tree sharing, as I am
>> > > still not clear about the tree sharing rules. (Did I mentioned it in
>> > > original email?)
>> >
>> > Yes. I don't know anything about tree sharing rules. I expect we
>> > can't share much.
>>
>> I think we do pretty heavy shaing via CCP that does move around the
>> constant PLUS_EXPRs and friends. I am not even aware of way to copy
>> tree expressions.
>> I wrote the code for testing and will run it once my other bootstrap
>> finish and come back with results.
>OK, first possitive in bootstrap is not very far:
>stage1/xgcc -Bstage1/ -B/usr/local/i686-pc-linux-gnu/bin/ -c -g -O2
>-DIN_GCC -W -Wall -Wwrite-strings -Wstrict-prototypes
>-Wmissing-prototypes -pedantic -Wno-long-long -Wold-style-definition
>-Werror -fno-common -DHAVE_CONFIG_H -DGENERATOR_FILE -I. -I.
>-I../../gcc -I../../gcc/.
>-I../../gcc/../include ../../gcc/gengtype.c -o gengtype.o
>(const char *)"*x";
>
>../../gcc/gengtype.c: In function `write_local_func_for_structure':
>
>../../gcc/gengtype.c:2184: error: Wrong sharing of tree nodes
>../../gcc/gengtype.c:2184: internal compiler error: verify_stmts failed.
>
>
>A shared NOP. Is this valid? If not, how to duplicate the nodes in CCP?
Not enough context to know if it's valid.
I would expect a NOP of a constant to be shared since that's still a
constant and we generally try to share constants.
jeff