Committed to mainline the patch to support instructions with auto-inc
operations in SMS after addressing Ayal's comments. The patch contains
two parts; one of them fixes a bug revealed during bootstrapping with
the patch and SMS flags.
http://gcc.gnu.org/ml/gcc-patches/2011-09/msg01988.htmlhttp://gcc.gnu.org/ml/gcc-patches/2011-09/msg01987.html
Looking at estimating register pressure with SMS: based on previous
discussion with Richard the current approach is to try and use the
register pressure estimation in loop invariant pass.
I'm compiling an application built with TI's DVSDK 3 *[0].
/home/user/ti/dvsdk/dvsdk_3_01_00_10/linuxutils_2_25_02_08/packages/ti/sdo/linuxutils/cmem/lib/cmem.a470MV(cmem.o470MV):(.ARM.exidx+0x0):
undefined reference to `__aeabi_unwind_cpp_pr0'
arm-linux-gnueabi-gcc --version
arm-linux-gnueabi-gcc (Ubuntu/Linaro 4.5.2-5ubuntu2~ppa1) 4.5.2
arm-linux-gnueabi-ld --version
GNU ld (GNU Binutils for Ubuntu) 2.21.0.20110302
More full output is here (but it isn't particularly helpful due to TI's RTSC
make system's black-magic)
https://gist.github.com/925674
FYI: the MV in cmem.a470MV stands for MontaVista.
This name is hard-coded somewhere even though it's not being linked against
a MontaVista system.
I believe the 470 means that it should work with ARMv4 through ARMv7, but
I'm not positive.
My googling suggest that this is a toolchain bug and that the best way
around the issue is to create a file which defines the function as a void
dummy and include it.
http://www.codesourcery.com/archives/arm-gnu/msg03604.htmlhttp://comments.gmane.org/gmane.comp.boot-loaders.u-boot/78649http://www.cs.fsu.edu/~baker/devices/lxr/http/ident?i=__aeabi_unwind_cpp_pr0
I have a script that I'll post shortly with instructions as to how to setup
TI's DVSDK with Linaro
AJ ONeal
[0] I'm not using the latest DVSDK version 4 because the paths and such are
so hard-coded for the 2009q3 version of codesourcery on ubuntu 10.04 LTS
that I don't know where to start fixing it.
===Progress===
* Patch review week.
* Looked at bootstrap issue for a while but Richard Sandiford picked
it up and sorted it out (Thanks Richard).
* Fun and games with some paperwork.
* Some backporting and testing patches. (50099 and 50186) underway.
=== Plans ===
* Clear out some of the old patches (POST_MODIFY_DISP for vfp,
BRANCH_COST ) and finish on auto-inc-dec patch from last week.
* Away for 1 day next week.
Meetings:
* 1-1s
* TCWG calls
Absences.
* 5th October -Out of Office.
* 13th - 14th October - Internal training.
* 31st Oct - 4th Nov - Linaro Summit Orlando.
* 08 Nov - 11 Nov - Tentatively booked
* Dec 19 - 31st Dec - Tentatively booked
== This week ==
* Applied patch for doing NEON high/low extraction using subregs.
Ramana pointed out that we do the same thing for insertion,
so I wrote a patch to handle that too. Both now merged into
Linaro sources.
* Looked at ARM bootstrap problem on trunk. Turned out to be
an aliasing problem. Submitted and applied patch.
* Reworked part of my SMS register-scheduling patch after feedback
from Ayal. Submitted new version upstream.
* Got SPEC2006 running on the powerpc boxes and tested one part
of my -fsched-pressure patch. Bit of a mixed bag. h264ref was
one of the worst sufferers, which was a bit worrying. I think
I'll need to make a third change too.
To recap, there are two pieces now:
1) Make -fsched-pressure honour the DFA
2) Make -fsched-pressure allow values that are live across a
loop to be spilled.
I naively hoped that (1) would be OK on its own, but h264 shows
that the current -fsched-pressure code is very conservative
when it comes to large blocks. It only considers register
deaths once there is a single remaining use; if there are two
unscheduled uses, it assumes that the register remains live
for the rest of the block.
So the problem that (1) was fixing was that -fsched-pressure was too
optimistic in terms of what it could schedule in a cycle. But with
that fixed, we seem to have too many sources of pessimism...
Richard
== GDB ==
* Worked on support for cross-platform core file generation.
* Followed up on patch to support disabling address space
randomization in gdbserver.
== GCC ==
* Followed up on patch for PR 50305.
Mit freundlichen Gruessen / Best Regards
Ulrich Weigand
--
Dr. Ulrich Weigand | Phone: +49-7031/16-3727
STSM, GNU compiler and toolchain for Linux on System z and Cell/B.E.
IBM Deutschland Research & Development GmbH
Vorsitzender des Aufsichtsrats: Martin Jetter | Geschäftsführung: Dirk
Wittkopp
Sitz der Gesellschaft: Böblingen | Registergericht: Amtsgericht
Stuttgart, HRB 243294
* Working on croos-compiling Firefox. Getting dependencies in place and
setting up the configuration file (.mozconfig). I have had the strategy to
fix one dependency at a time, picking prebuilt packages or building my self.
Michael told me at yesterday's meeting about multistrap, that could possibly
be used for fixing all dependencies at once. I will look into that next
week.
* During this process I have also spent some time reading up on cross
compilation in general and also on autoconf and the GNU build system.
Best Regards
Åsa
== String routines ==
* Got eglibc testing setup happy at last
- Note that -O3 builds generally seem to give a few more errors
that are probably worth looking at
- -march=armv6 -mthumb hit some non-thumb1 instructions (normally
non-lo registers), again worth looking at
- Cross testing to Qemu user mode often stalls, mostly on nptl
tests that abort/fail when run in system/natively
* Sent new version of eglibc/memchr patch upstream
* Now have working newlib test setup and reference set
- next step is to try adding my memchr there
== Other ==
* Testing a QEmu patch with Peter
* Looking at bug 861296 (difference in mmap layouts)
* Adding a few suggestions to the set of cpu hotplug tests.
* Dealing with the Manchester lab cold.
Short week; back on Monday
Dave
== GDB ==
* Committed hardware watchpoint support for gdbserver to mainline,
including two minor changes resulting from review comments;
backported those fixes to Linaro GDB as well.
* Implemented and tested support for disabling address space
randomization in gdbserver; patch posted for review.
* Investigated support for cross-platform core file generation.
== GCC ==
* Patch review week.
* Posted updated patch for PR 50305.
Mit freundlichen Gruessen / Best Regards
Ulrich Weigand
--
Dr. Ulrich Weigand | Phone: +49-7031/16-3727
STSM, GNU compiler and toolchain for Linux on System z and Cell/B.E.
IBM Deutschland Research & Development GmbH
Vorsitzender des Aufsichtsrats: Martin Jetter | Geschäftsführung: Dirk
Wittkopp
Sitz der Gesellschaft: Böblingen | Registergericht: Amtsgericht
Stuttgart, HRB 243294
