http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59728
Andrew Pinski <pinskia at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Keywords| |missed-optimization Status|UNCONFIRMED |NEW Last reconfirmed| |2014-01-08 Component|target |rtl-optimization Target Milestone|--- |4.9.0 Summary|gcc.target/mips/octeon-badd |[4.9 Regression] |u-1.c is failing |gcc.target/mips/octeon-badd | |u-1.c is failing Ever confirmed|0 |1 --- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> --- (In reply to Steve Ellcey from comment #0) > I am not sure exactly what checkin caused this change or if the change > in generated code is correct or not. The generated code is correct just non-optimal. The most likely candidate patch which caused this performance regression is: 2013-12-10 Eric Botcazou <ebotca...@adacore.com> PR rtl-optimization/58295 * simplify-rtx.c (simplify_truncation): Restrict the distribution for WORD_REGISTER_OPERATIONS targets. Which was partly expected and octeon's baddu instruction was mentioned in the thread about this patch too.