Command line:
gcc -O1 -fschedule-insns2 -fsched2-use-superblocks -m32 testcase.c && ./a.out
or
gcc -O2 -fsched2-use-superblocks -m32 testcase.c && ./a.out
Tested revisions:
r157965 - fail
r157877 - fail
r153685 - OK
4.4.3, 4.3.4, 4.2.4, 4.1.2, 3.4.6 - OK
Output:
$ /mnt/svn/gcc-trunk/binary-157965-lto/bin/gcc -O1 -fschedule-insns2
-fsched2-use-superblocks -m32 testcase.c && ./a.out
Aborted
The problem is the value is read before stored:
(reduced testcase, -O1 version)
...
pxor %xmm0, %xmm0 # tmp63
...
cmpl $0, 4(%esp) #, u.i
movdqa %xmm0, (%esp) # tmp63, u.v
jne .L2 #,
...
.L2:
call abort #
--
Summary: -fsched2-use-superblocks -m32 causes FAIL:
gcc.dg/pr32912-1.c execution test
Product: gcc
Version: 4.5.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: zsojka at seznam dot cz
GCC host triplet: x86_64-pc-linux-gnu
GCC target triplet: i686-pc-linux-gnu
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43671
