------- Comment #1 from dorit at gcc dot gnu dot org 2007-08-29 09:04 ------- > In the testcase below, after the inner-loop gets completely unrolled, the > enclosing i-loop does not get unrolled because of failure to analyze the loop > iv, possibly due to a bug in df: ... > Compiler options used: > /Develop/mainline-dn1/bin/gcc -O3 -maltivec -funroll-loops > vect-outer-fir2-kernel.c -S --param max-completely-peeled-insns=5000 --param > max-completely-peel-times=40 -fdump-tree-all -da -ftree-vectorize > (without -ftree-vectorize the i-loop does get unrolled).
(it could be ofcourse a result of something the vectorizer does. like, maybe the vectorizer is not updating the dominance information correctly or something. but I'd think most such information would be recomputed and verified between vectorization and rtl unrolling? anyhow, verify_dominance seem to pass). -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33224