#include "params.h"
#include "sched-int.h"
#include "target.h"
+#include "timevar.h"
+#include "tree-pass.h"
/* Define when we want to do count REG_DEAD notes before and after scheduling
for sanity checking. We can't do that when conditional execution is used,
static void
extract_edgelst (sbitmap set, edgelst *el)
{
- unsigned int i;
+ unsigned int i = 0;
sbitmap_iterator sbi;
/* edgelst table space is reused in each call to extract_edgelst. */
cc0 setters remain at the end because they can't be moved away from
their cc0 user.
+ COND_EXEC insns cannot be moved past a branch (see e.g. PR17808).
+
Insns setting CLASS_LIKELY_SPILLED_P registers (usually return values)
are not moved before reload because we can wind up with register
allocation failures. */
{
if (last != 0 && !find_insn_list (insn, LOG_LINKS (last)))
{
- add_dependence (last, insn, REG_DEP_ANTI);
+ if (! sched_insns_conditions_mutex_p (last, insn))
+ add_dependence (last, insn, REG_DEP_ANTI);
INSN_REF_COUNT (insn)++;
}
if (INSN_REF_COUNT (insn) != 0)
continue;
- add_dependence (last, insn, REG_DEP_ANTI);
+ if (! sched_insns_conditions_mutex_p (last, insn))
+ add_dependence (last, insn, REG_DEP_ANTI);
INSN_REF_COUNT (insn) = 1;
}
+
+#ifdef HAVE_conditional_execution
+ /* Finally, if the block ends in a jump, and we are doing intra-block
+ scheduling, make sure that the branch depends on any COND_EXEC insns
+ inside the block to avoid moving the COND_EXECs past the branch insn.
+
+ We only have to do this after reload, because (1) before reload there
+ are no COND_EXEC insns, and (2) the region scheduler is an intra-block
+ scheduler after reload.
+
+ FIXME: We could in some cases move COND_EXEC insns past the branch if
+ this scheduler would be a little smarter. Consider this code:
+
+ T = [addr]
+ C ? addr += 4
+ !C ? X += 12
+ C ? T += 1
+ C ? jump foo
+
+ On a target with a one cycle stall on a memory access the optimal
+ sequence would be:
+
+ T = [addr]
+ C ? addr += 4
+ C ? T += 1
+ C ? jump foo
+ !C ? X += 12
+
+ We don't want to put the 'X += 12' before the branch because it just
+ wastes a cycle of execution time when the branch is taken.
+
+ Note that in the example "!C" will always be true. That is another
+ possible improvement for handling COND_EXECs in this scheduler: it
+ could remove always-true predicates. */
+
+ if (!reload_completed || ! JUMP_P (tail))
+ return;
+
+ insn = tail;
+ while (insn != head)
+ {
+ insn = PREV_INSN (insn);
+
+ /* Note that we want to add this dependency even when
+ sched_insns_conditions_mutex_p returns true. The whole point
+ is that we _want_ this dependency, even if these insns really
+ are independent. */
+ if (INSN_P (insn) && GET_CODE (PATTERN (insn)) == COND_EXEC)
+ add_dependence (tail, insn, REG_DEP_ANTI);
+ }
+#endif
}
/* Data structures for the computation of data dependences in a regions. We
sbitmap_free (large_region_blocks);
}
#endif
+\f
+static bool
+gate_handle_sched (void)
+{
+#ifdef INSN_SCHEDULING
+ return flag_schedule_insns;
+#else
+ return 0;
+#endif
+}
+
+/* Run instruction scheduler. */
+static void
+rest_of_handle_sched (void)
+{
+#ifdef INSN_SCHEDULING
+ /* Do control and data sched analysis,
+ and write some of the results to dump file. */
+
+ schedule_insns (dump_file);
+#endif
+}
+
+static bool
+gate_handle_sched2 (void)
+{
+#ifdef INSN_SCHEDULING
+ return optimize > 0 && flag_schedule_insns_after_reload;
+#else
+ return 0;
+#endif
+}
+
+/* Run second scheduling pass after reload. */
+static void
+rest_of_handle_sched2 (void)
+{
+#ifdef INSN_SCHEDULING
+ /* Do control and data sched analysis again,
+ and write some more of the results to dump file. */
+
+ split_all_insns (1);
+
+ if (flag_sched2_use_superblocks || flag_sched2_use_traces)
+ {
+ schedule_ebbs (dump_file);
+ /* No liveness updating code yet, but it should be easy to do.
+ reg-stack recomputes the liveness when needed for now. */
+ count_or_remove_death_notes (NULL, 1);
+ cleanup_cfg (CLEANUP_EXPENSIVE);
+ }
+ else
+ schedule_insns (dump_file);
+#endif
+}
+
+struct tree_opt_pass pass_sched =
+{
+ "sched1", /* name */
+ gate_handle_sched, /* gate */
+ rest_of_handle_sched, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ TV_SCHED, /* tv_id */
+ 0, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ TODO_dump_func |
+ TODO_ggc_collect, /* todo_flags_finish */
+ 'S' /* letter */
+};
+
+struct tree_opt_pass pass_sched2 =
+{
+ "sched2", /* name */
+ gate_handle_sched2, /* gate */
+ rest_of_handle_sched2, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ TV_SCHED2, /* tv_id */
+ 0, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ TODO_dump_func |
+ TODO_ggc_collect, /* todo_flags_finish */
+ 'R' /* letter */
+};
+
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