The pattern subqi_2 and subqi_3 contain a reference to a construct (minus:HI (match_operand:QI) (match_operand:QI)). It is not obvious because the match_operand are written as match_dup. Such a RTL will never be generated.
-- Summary: X86: wrong mode in subqi_2 Product: gcc Version: 4.4.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: target AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: Erwin dot Unruh at fujitsu-siemens dot com GCC build triplet: x86_64-unknown-linux-gnu GCC host triplet: x86_64-unknown-linux-gnu GCC target triplet: x86_64-unknown-linux-gnu http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36627