https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85645
--- Comment #15 from Segher Boessenkool <segher at gcc dot gnu.org> --- Author: segher Date: Tue Jun 26 15:39:02 2018 New Revision: 262155 URL: https://gcc.gnu.org/viewcvs?rev=262155&root=gcc&view=rev Log: regrename: Don't rename the dest of a REG_CFA_REGISTER (PR85645) We should never change the destination of a REG_CFA_REGISTER, just like for insns with a REG_CFA_RESTORE, because we need to have the same control flow information on all branches that join. It is very doubtful that renaming the scratch registers used for prologue/epilogue will help anything either. Backport from trunk 2018-05-08 Segher Boessenkool <seg...@kernel.crashing.org> PR rtl-optimization/85645 * regrename.c (build_def_use): Also kill the chains that include the destination of a REG_CFA_REGISTER note. Modified: branches/gcc-8-branch/gcc/ChangeLog branches/gcc-8-branch/gcc/regrename.c
