2014-09-10 Andreas Krebbel PR target/62662 * config/s390/s390.c (s390_emit_epilogue): When doing the return address load optimization force s390_optimize_prologue to leave it that way. Only do the optimization if we already decided to push r14 into a stack slot. --- gcc/config/s390/s390.c +++ gcc/config/s390/s390.c @@ -9082,11 +9082,14 @@ s390_emit_epilogue (bool sibcall) if (! sibcall) { /* Fetch return address from stack before load multiple, - this will do good for scheduling. */ - - if (cfun_frame_layout.save_return_addr_p - || (cfun_frame_layout.first_restore_gpr < BASE_REGNUM - && cfun_frame_layout.last_restore_gpr > RETURN_REGNUM)) + this will do good for scheduling. + + Only do this if we already decided that r14 needs to be + saved to a stack slot. (And not just because r14 happens to + be in between two GPRs which need saving.) Otherwise it + would be difficult to take that decision back in + s390_optimize_prologue. */ + if (cfun_gpr_save_slot (RETURN_REGNUM) == -1) { int return_regnum = find_unused_clobbered_reg(); if (!return_regnum) @@ -9101,6 +9104,13 @@ s390_emit_epilogue (bool sibcall) addr = gen_rtx_MEM (Pmode, addr); set_mem_alias_set (addr, get_frame_alias_set ()); emit_move_insn (return_reg, addr); + + /* Once we did that optimization we have to make sure + s390_optimize_prologue does not try to remove the + store of r14 since we will not be able to find the + load issued here. */ + cfun_frame_layout.save_return_addr_p = true; + cfun_gpr_save_slot (RETURN_REGNUM) = -1; } }