[Bug bootstrap/49789] New: Bootstrap failure with SMS flags on ARM

["revital.eres at linaro dot org" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49789

           Summary: Bootstrap failure with SMS flags on ARM
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: bootstrap
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: revital.eres@linaro.org
              Host: arm-linux-gnueabi
            Target: arm-linux-gnueabi


I get the following error while bootstrap trunk -r176434 on ARM machine with
SMS flags:

-O2 -fmodulo-sched -fmodulo-sched-allow-regmoves  -fno-auto-inc-dec --param
sms-min-sc=1

configure:3269: /home/40014/mainline/build3/./gcc/xgcc
-B/home/40014/mainline/build3/./gcc/
-B/home/40014/mainline/build3/armv7l-unknown-linux-gnueabi/bin/
-B/home/40014/mainline/build3/armv7l-unknown-linux-gnueabi/lib/ -isystem
/home/40014/mainline/build3/armv7l-unknown-linux-gnueabi/include -isystem
/home/40014/mainline/build3/armv7l-unknown-linux-gnueabi/sys-include    -c -g
-O2  conftest.c >&5
conftest.c: In function 'main':
conftest.c:16:1: internal compiler error: vector VEC(edge,base) index domain
error, in ei_edge at basic-block.h:672
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.
configure:3273: $? = 1

Investigating the problem; it seems that the cause is not related to
SMS but rather to the doloop optimization which is enabled only when
SMS flags are set. (but that also does not mean that doloop is the
reason for the fail; it could be some later passes)
The first file that doloop is applied on and causes bootstrap failure
is bb-reorder.c.
The problematic loop seems to be the last FOR_EACH_EDGE in
connect_traces function which is inlined into reorder_basic_block.