https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115866
--- Comment #5 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The trunk branch has been updated by Andi Kleen <a...@gcc.gnu.org>: https://gcc.gnu.org/g:c9ccc3961f5b8d333f5081b377cd9ee9e33079f7 commit r15-3167-gc9ccc3961f5b8d333f5081b377cd9ee9e33079f7 Author: Andi Kleen <a...@gcc.gnu.org> Date: Thu Aug 1 20:10:27 2024 -0700 Support if conversion for switches The gimple-if-to-switch pass converts if statements with multiple equal checks on the same value to a switch. This breaks vectorization which cannot handle switches. Teach the tree-if-conv pass used by the vectorizer to handle simple switch statements, like those created by if-to-switch earlier. These are switches that only have a single non default block, They are handled similar to COND in if conversion. This makes the vect-bitfield-read-1-not test fail. The test checks for a bitfield analysis failing, but it actually relied on the ifcvt erroring out early because the test is using a switch. The if conversion still does not work because the switch is not in a form that this patch can handle, but it fails much later and the bitfield analysis succeeds, which makes the test fail. I marked it xfail because it doesn't seem to be testing what it wants to test. PR tree-optimization/115866 gcc/ChangeLog: * tree-if-conv.cc (if_convertible_switch_p): New function. (if_convertible_stmt_p): Check for switch. (get_loop_body_in_if_conv_order): Handle switch. (predicate_bbs): Likewise. (predicate_statements): Likewise. (remove_conditions_and_labels): Likewise. (ifcvt_split_critical_edges): Likewise. (ifcvt_local_dce): Likewise. gcc/testsuite/ChangeLog: * gcc.dg/vect/vect-switch-ifcvt-1.c: New test. * gcc.dg/vect/vect-switch-ifcvt-2.c: New test. * gcc.dg/vect/vect-switch-search-line-fast.c: New test. * gcc.dg/vect/vect-bitfield-read-1-not.c: Change to xfail.
