Item 122 from the old PROBLEMS file (no test case available):
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When insn-output.c turns a bit-test into a sign-test, it should
see whether the condition code is already set up with that sign.
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Summary: [cc0] insn-output.c should optimize sign-tests better
Product: gcc
Version: unknown
Status: UNCONFIRMED
Keywords: missed-optimization
Severity: enhancement
Priority: P2
Component: middle-end
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: steven at gcc dot gnu dot org
CC: gcc-bugs at gcc dot gnu dot org
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19206
