ifcvt: Do not lower bitfields if we can't analyze dr's [PR107275]

The ifcvt dead code elimination code was not built to deal with inline
assembly, loops with such would never be if-converted in the past since we can't
do data-reference analysis on them and vectorization would eventually fail.  For
this reason we now also do not lower bitfields if the data-reference analysis
fails, as we would not end up vectorizing it.  As a consequence this also fixes
this PR as the dead code elimination will not run for such cases and wrongfully
eliminate inline assembly statements.

gcc/ChangeLog:

	PR tree-optimization/107275
	* tree-if-conv.cc (if_convertible_loop_p_1): Move
	find_data_references_in_loop call from here...
	(if_convertible_loop_p): And move data-reference vector initialization
	from here...
	(tree_if_conversion):... to here.

gcc/testsuite/ChangeLog:

	* gcc.dg/vect/pr107275.c: New test.

0 files changed, 0 insertions, 0 deletions