Revision c95ec459
| ID | c95ec459c6c39b7a7e1850f82abd95eca4ccfcce |
target-s390: Optimize ADDC/SUBB
Giving the proper mask to disas_jcc allows us to generate an inline
comparison generating the carry/borrow with setcond.
In the very worst case, when we must use the external helper to compute
a value for CC, we generate (cc > 1) instead of (cc >> 1), which is only
very slightly slower on common cpus.
In the very best case, when the CC comes from a COMPARE insn and the
compiler is using ALCG with zero, everything folds out to become just
the setcond that the compiler wanted.
Signed-off-by: Richard Henderson <rth@twiddle.net>
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