Message ID | alpine.LNX.2.00.1104072116220.17990@monoid.intra.ispras.ru |
---|---|
State | New |
Headers | show |
On 04/07/2011 01:30 PM, Alexander Monakov wrote: > Hi, > > Selective scheduler does not explicitly forbid creating bookkeeping copies of > CALLs, but an assert in create_copy_of_insn_rtx does not expect a CALL. Since > there's little benefit from aggressive scheduling of CALLs, it makes sense to > restrict it so that CALLs cannot be duplicated. > > This patch makes CALLs non-clonable by adding an explicit check in additional > to other non-clonable insns (ASMs, instructions that are a part of > SCHED_GROUPs, etc.). We also need to forbid pipelining of loops that have no > exit edges, since our check for whether a motion would create bookkeeping does > not work in that case (it's one of the solutions; the other is to fixup > remove_insns_that_need_bookkeeping function, but this one is simpler and > faster). > > > PR target/48273 > * cfgloop.h (loop_has_exit_edges): New helper. > * sel-sched-ir.c (init_global_and_expr_for_insn): Make CALLs > non-clonable. > (sel_setup_region_sched_flags): Don't pipeline loops that have no > exit edges. > > testsuite: > * g++.dg/opt/pr48273.C: New. > Ok, thanks.
diff --git a/gcc/cfgloop.h b/gcc/cfgloop.h index f7bb134..0ff44de 100644 --- a/gcc/cfgloop.h +++ b/gcc/cfgloop.h @@ -443,6 +443,14 @@ loop_outer (const struct loop *loop) return VEC_index (loop_p, loop->superloops, n - 1); } +/* Returns true if LOOP has at least one exit edge. */ + +static inline bool +loop_has_exit_edges (const struct loop *loop) +{ + return loop->exits->next->e != NULL; +} + /* Returns the list of loops in current_loops. */ static inline VEC (loop_p, gc) * diff --git a/gcc/sel-sched-ir.c b/gcc/sel-sched-ir.c index 67484dd..95c1431 100644 --- a/gcc/sel-sched-ir.c +++ b/gcc/sel-sched-ir.c @@ -2905,6 +2905,7 @@ init_global_and_expr_for_insn (insn_t insn) if (CANT_MOVE (insn) || INSN_ASM_P (insn) || SCHED_GROUP_P (insn) + || CALL_P (insn) /* Exception handling insns are always unique. */ || (cfun->can_throw_non_call_exceptions && can_throw_internal (insn)) /* TRAP_IF though have an INSN code is control_flow_insn_p (). */ diff --git a/gcc/sel-sched.c b/gcc/sel-sched.c index 0e8173b..fb1a026 100644 --- a/gcc/sel-sched.c +++ b/gcc/sel-sched.c @@ -6781,7 +6781,8 @@ sel_setup_region_sched_flags (void) bookkeeping_p = 1; pipelining_p = (bookkeeping_p && (flag_sel_sched_pipelining != 0) - && current_loop_nest != NULL); + && current_loop_nest != NULL + && loop_has_exit_edges (current_loop_nest)); max_insns_to_rename = PARAM_VALUE (PARAM_SELSCHED_INSNS_TO_RENAME); max_ws = MAX_WS; } diff --git a/gcc/testsuite/g++.dg/opt/pr48273.C b/gcc/testsuite/g++.dg/opt/pr48273.C new file mode 100644 index 0000000..4c5108b --- /dev/null +++ b/gcc/testsuite/g++.dg/opt/pr48273.C @@ -0,0 +1,10 @@ +// { dg-do compile { target x86_64-*-* } } +// { dg-options "-fschedule-insns2 -fsel-sched-pipelining -fselective-scheduling2 -funroll-all-loops -march=core2" } + +void bar (); + +void foo () +{ + for (;;) + bar (); +}