/* Instruction scheduling pass.
- Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998,
- 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
- Free Software Foundation, Inc.
+ Copyright (C) 1992-2015 Free Software Foundation, Inc.
Contributed by Michael Tiemann (tiemann@cygnus.com) Enhanced by,
and currently maintained by, Jim Wilson (wilson@cygnus.com)
#include "system.h"
#include "coretypes.h"
#include "tm.h"
-#include "toplev.h"
+#include "diagnostic-core.h"
#include "rtl.h"
#include "tm_p.h"
#include "hard-reg-set.h"
#include "regs.h"
#include "function.h"
+#include "profile.h"
#include "flags.h"
#include "insn-config.h"
#include "insn-attr.h"
#include "except.h"
-#include "toplev.h"
#include "recog.h"
-#include "cfglayout.h"
#include "params.h"
+#include "dominance.h"
+#include "cfg.h"
+#include "cfgrtl.h"
+#include "cfgbuild.h"
+#include "predict.h"
+#include "basic-block.h"
#include "sched-int.h"
#include "target.h"
-#include "output.h"
\f
#ifdef INSN_SCHEDULING
/* Implementations of the sched_info functions for region scheduling. */
static void init_ready_list (void);
-static void begin_schedule_ready (rtx, rtx);
+static void begin_schedule_ready (rtx_insn *);
static int schedule_more_p (void);
-static const char *ebb_print_insn (const_rtx, int);
-static int rank (rtx, rtx);
-static int ebb_contributes_to_priority (rtx, rtx);
+static const char *ebb_print_insn (const rtx_insn *, int);
+static int rank (rtx_insn *, rtx_insn *);
+static int ebb_contributes_to_priority (rtx_insn *, rtx_insn *);
static basic_block earliest_block_with_similiar_load (basic_block, rtx);
-static void add_deps_for_risky_insns (rtx, rtx);
-static basic_block schedule_ebb (rtx, rtx);
-static void debug_ebb_dependencies (rtx, rtx);
+static void add_deps_for_risky_insns (rtx_insn *, rtx_insn *);
+static void debug_ebb_dependencies (rtx_insn *, rtx_insn *);
-static void ebb_add_remove_insn (rtx, int);
+static void ebb_add_remove_insn (rtx_insn *, int);
static void ebb_add_block (basic_block, basic_block);
-static basic_block advance_target_bb (basic_block, rtx);
+static basic_block advance_target_bb (basic_block, rtx_insn *);
static void ebb_fix_recovery_cfg (int, int, int);
+/* Allocate memory and store the state of the frontend. Return the allocated
+ memory. */
+static void *
+save_ebb_state (void)
+{
+ int *p = XNEW (int);
+ *p = sched_rgn_n_insns;
+ return p;
+}
+
+/* Restore the state of the frontend from P_, then free it. */
+static void
+restore_ebb_state (void *p_)
+{
+ int *p = (int *)p_;
+ sched_rgn_n_insns = *p;
+ free (p_);
+}
+
/* Return nonzero if there are more insns that should be scheduled. */
static int
/* Print dependency information about ebb between HEAD and TAIL. */
static void
-debug_ebb_dependencies (rtx head, rtx tail)
+debug_ebb_dependencies (rtx_insn *head, rtx_insn *tail)
{
fprintf (sched_dump,
";; --------------- forward dependences: ------------ \n");
init_ready_list (void)
{
int n = 0;
- rtx prev_head = current_sched_info->prev_head;
- rtx next_tail = current_sched_info->next_tail;
- rtx insn;
+ rtx_insn *prev_head = current_sched_info->prev_head;
+ rtx_insn *next_tail = current_sched_info->next_tail;
+ rtx_insn *insn;
sched_rgn_n_insns = 0;
/* INSN is being scheduled after LAST. Update counters. */
static void
-begin_schedule_ready (rtx insn, rtx last)
+begin_schedule_ready (rtx_insn *insn ATTRIBUTE_UNUSED)
{
sched_rgn_n_insns++;
+}
+/* INSN is being moved to its place in the schedule, after LAST. */
+static void
+begin_move_insn (rtx_insn *insn, rtx_insn *last)
+{
if (BLOCK_FOR_INSN (insn) == last_bb
/* INSN is a jump in the last block, ... */
&& control_flow_insn_p (insn)
&& last != PREV_INSN (insn))
{
edge e;
- edge_iterator ei;
basic_block bb;
/* An obscure special case, where we do have partially dead
instruction scheduled after last control flow instruction.
In this case we can create new basic block. It is
always exactly one basic block last in the sequence. */
-
- FOR_EACH_EDGE (e, ei, last_bb->succs)
- if (e->flags & EDGE_FALLTHRU)
- break;
-#ifdef ENABLE_CHECKING
- gcc_assert (!e || !(e->flags & EDGE_COMPLEX));
+ e = find_fallthru_edge (last_bb->succs);
- gcc_assert (BLOCK_FOR_INSN (insn) == last_bb
- && !IS_SPECULATION_CHECK_P (insn)
- && BB_HEAD (last_bb) != insn
- && BB_END (last_bb) == insn);
+ gcc_checking_assert (!e || !(e->flags & EDGE_COMPLEX));
- {
- rtx x;
+ gcc_checking_assert (BLOCK_FOR_INSN (insn) == last_bb
+ && !IS_SPECULATION_CHECK_P (insn)
+ && BB_HEAD (last_bb) != insn
+ && BB_END (last_bb) == insn);
- x = NEXT_INSN (insn);
+ {
+ rtx_insn *x = NEXT_INSN (insn);
if (e)
- gcc_assert (NOTE_P (x) || LABEL_P (x));
+ gcc_checking_assert (NOTE_P (x) || LABEL_P (x));
else
- gcc_assert (BARRIER_P (x));
+ gcc_checking_assert (BARRIER_P (x));
}
-#endif
if (e)
{
gcc_assert (NOTE_INSN_BASIC_BLOCK_P (BB_END (bb)));
}
else
- /* Create an empty unreachable block after the INSN. */
- bb = create_basic_block (NEXT_INSN (insn), NULL_RTX, last_bb);
-
+ {
+ /* Create an empty unreachable block after the INSN. */
+ rtx_insn *next = NEXT_INSN (insn);
+ if (next && BARRIER_P (next))
+ next = NEXT_INSN (next);
+ bb = create_basic_block (next, NULL_RTX, last_bb);
+ }
+
/* split_edge () creates BB before E->DEST. Keep in mind, that
this operation extends scheduling region till the end of BB.
Hence, we need to shift NEXT_TAIL, so haifa-sched.c won't go out
to be formatted so that multiple output lines will line up nicely. */
static const char *
-ebb_print_insn (const_rtx insn, int aligned ATTRIBUTE_UNUSED)
+ebb_print_insn (const rtx_insn *insn, int aligned ATTRIBUTE_UNUSED)
{
static char tmp[80];
is to be preferred. Zero if they are equally good. */
static int
-rank (rtx insn1, rtx insn2)
+rank (rtx_insn *insn1, rtx_insn *insn2)
{
basic_block bb1 = BLOCK_FOR_INSN (insn1);
basic_block bb2 = BLOCK_FOR_INSN (insn2);
calculations. */
static int
-ebb_contributes_to_priority (rtx next ATTRIBUTE_UNUSED,
- rtx insn ATTRIBUTE_UNUSED)
+ebb_contributes_to_priority (rtx_insn *next ATTRIBUTE_UNUSED,
+ rtx_insn *insn ATTRIBUTE_UNUSED)
{
return 1;
}
- /* INSN is a JUMP_INSN, COND_SET is the set of registers that are
- conditionally set before INSN. Store the set of registers that
- must be considered as used by this jump in USED and that of
- registers that must be considered as set in SET. */
+ /* INSN is a JUMP_INSN. Store the set of registers that
+ must be considered as used by this jump in USED. */
void
-ebb_compute_jump_reg_dependencies (rtx insn, regset cond_set, regset used,
- regset set)
+ebb_compute_jump_reg_dependencies (rtx insn, regset used)
{
basic_block b = BLOCK_FOR_INSN (insn);
edge e;
edge_iterator ei;
FOR_EACH_EDGE (e, ei, b->succs)
- if (e->flags & EDGE_FALLTHRU)
- /* The jump may be a by-product of a branch that has been merged
- in the main codepath after being conditionalized. Therefore
- it may guard the fallthrough block from using a value that has
- conditionally overwritten that of the main codepath. So we
- consider that it restores the value of the main codepath. */
- bitmap_and (set, df_get_live_in (e->dest), cond_set);
- else
+ if ((e->flags & EDGE_FALLTHRU) == 0)
bitmap_ior_into (used, df_get_live_in (e->dest));
}
rank,
ebb_print_insn,
ebb_contributes_to_priority,
+ NULL, /* insn_finishes_block_p */
NULL, NULL,
NULL, NULL,
ebb_add_remove_insn,
begin_schedule_ready,
+ begin_move_insn,
advance_target_bb,
+
+ save_ebb_state,
+ restore_ebb_state,
+
SCHED_EBB
/* We can create new blocks in begin_schedule_ready (). */
| NEW_BBS
FOR_EACH_DEP (load_insn, SD_LIST_BACK, back_sd_it, back_dep)
{
- rtx insn1 = DEP_PRO (back_dep);
+ rtx_insn *insn1 = DEP_PRO (back_dep);
- if (DEP_TYPE (back_dep) == REG_DEP_TRUE)
+ if (DEP_TYPE (back_dep) == REG_DEP_TRUE)
/* Found a DEF-USE dependence (insn1, load_insn). */
{
sd_iterator_def fore_sd_it;
FOR_EACH_DEP (insn1, SD_LIST_FORW, fore_sd_it, fore_dep)
{
- rtx insn2 = DEP_CON (fore_dep);
+ rtx_insn *insn2 = DEP_CON (fore_dep);
basic_block insn2_block = BLOCK_FOR_INSN (insn2);
if (DEP_TYPE (fore_dep) == REG_DEP_TRUE)
insns in given ebb. */
static void
-add_deps_for_risky_insns (rtx head, rtx tail)
+add_deps_for_risky_insns (rtx_insn *head, rtx_insn *tail)
{
- rtx insn, prev;
+ rtx_insn *insn, *prev;
int classification;
- rtx last_jump = NULL_RTX;
- rtx next_tail = NEXT_INSN (tail);
+ rtx_insn *last_jump = NULL;
+ rtx_insn *next_tail = NEXT_INSN (tail);
basic_block last_block = NULL, bb;
for (insn = head; insn != next_tail; insn = NEXT_INSN (insn))
- if (control_flow_insn_p (insn))
- {
- bb = BLOCK_FOR_INSN (insn);
- bb->aux = last_block;
- last_block = bb;
- last_jump = insn;
- }
- else if (INSN_P (insn) && last_jump != NULL_RTX)
- {
- classification = haifa_classify_insn (insn);
- prev = last_jump;
- switch (classification)
- {
- case PFREE_CANDIDATE:
- if (flag_schedule_speculative_load)
- {
- bb = earliest_block_with_similiar_load (last_block, insn);
- if (bb)
- {
- bb = (basic_block) bb->aux;
- if (!bb)
- break;
- prev = BB_END (bb);
- }
- }
- /* Fall through. */
- case TRAP_RISKY:
- case IRISKY:
- case PRISKY_CANDIDATE:
- /* ??? We could implement better checking PRISKY_CANDIDATEs
- analogous to sched-rgn.c. */
- /* We can not change the mode of the backward
- dependency because REG_DEP_ANTI has the lowest
- rank. */
- if (! sched_insns_conditions_mutex_p (insn, prev))
- {
- dep_def _dep, *dep = &_dep;
-
- init_dep (dep, prev, insn, REG_DEP_ANTI);
-
- if (!(current_sched_info->flags & USE_DEPS_LIST))
- {
- enum DEPS_ADJUST_RESULT res;
-
- res = sd_add_or_update_dep (dep, false);
-
- /* We can't change an existing dependency with
- DEP_ANTI. */
- gcc_assert (res != DEP_CHANGED);
- }
- else
- {
- if ((current_sched_info->flags & DO_SPECULATION)
- && (spec_info->mask & BEGIN_CONTROL))
- DEP_STATUS (dep) = set_dep_weak (DEP_ANTI, BEGIN_CONTROL,
- MAX_DEP_WEAK);
-
- sd_add_or_update_dep (dep, false);
-
- /* Dep_status could have been changed.
- No assertion here. */
- }
- }
-
- break;
-
- default:
- break;
- }
- }
+ {
+ add_delay_dependencies (insn);
+ if (control_flow_insn_p (insn))
+ {
+ bb = BLOCK_FOR_INSN (insn);
+ bb->aux = last_block;
+ last_block = bb;
+ /* Ensure blocks stay in the same order. */
+ if (last_jump)
+ add_dependence (insn, last_jump, REG_DEP_ANTI);
+ last_jump = insn;
+ }
+ else if (INSN_P (insn) && last_jump != NULL_RTX)
+ {
+ classification = haifa_classify_insn (insn);
+ prev = last_jump;
+
+ switch (classification)
+ {
+ case PFREE_CANDIDATE:
+ if (flag_schedule_speculative_load)
+ {
+ bb = earliest_block_with_similiar_load (last_block, insn);
+ if (bb)
+ {
+ bb = (basic_block) bb->aux;
+ if (!bb)
+ break;
+ prev = BB_END (bb);
+ }
+ }
+ /* Fall through. */
+ case TRAP_RISKY:
+ case IRISKY:
+ case PRISKY_CANDIDATE:
+ /* ??? We could implement better checking PRISKY_CANDIDATEs
+ analogous to sched-rgn.c. */
+ /* We can not change the mode of the backward
+ dependency because REG_DEP_ANTI has the lowest
+ rank. */
+ if (! sched_insns_conditions_mutex_p (insn, prev))
+ {
+ if ((current_sched_info->flags & DO_SPECULATION)
+ && (spec_info->mask & BEGIN_CONTROL))
+ {
+ dep_def _dep, *dep = &_dep;
+
+ init_dep (dep, prev, insn, REG_DEP_ANTI);
+
+ if (current_sched_info->flags & USE_DEPS_LIST)
+ {
+ DEP_STATUS (dep) = set_dep_weak (DEP_ANTI, BEGIN_CONTROL,
+ MAX_DEP_WEAK);
+
+ }
+ sd_add_or_update_dep (dep, false);
+ }
+ else
+ add_dependence (insn, prev, REG_DEP_CONTROL);
+ }
+
+ break;
+
+ default:
+ break;
+ }
+ }
+ }
/* Maintain the invariant that bb->aux is clear after use. */
while (last_block)
{
}
}
-/* Schedule a single extended basic block, defined by the boundaries HEAD
- and TAIL. */
+/* Schedule a single extended basic block, defined by the boundaries
+ HEAD and TAIL.
-static basic_block
-schedule_ebb (rtx head, rtx tail)
+ We change our expectations about scheduler behaviour depending on
+ whether MODULO_SCHEDULING is true. If it is, we expect that the
+ caller has already called set_modulo_params and created delay pairs
+ as appropriate. If the modulo schedule failed, we return
+ NULL_RTX. */
+
+basic_block
+schedule_ebb (rtx_insn *head, rtx_insn *tail, bool modulo_scheduling)
{
basic_block first_bb, target_bb;
- struct deps tmp_deps;
-
+ struct deps_desc tmp_deps;
+ bool success;
+
+ /* Blah. We should fix the rest of the code not to get confused by
+ a note or two. */
+ while (head != tail)
+ {
+ if (NOTE_P (head) || DEBUG_INSN_P (head))
+ head = NEXT_INSN (head);
+ else if (NOTE_P (tail) || DEBUG_INSN_P (tail))
+ tail = PREV_INSN (tail);
+ else if (LABEL_P (head))
+ head = NEXT_INSN (head);
+ else
+ break;
+ }
+
first_bb = BLOCK_FOR_INSN (head);
last_bb = BLOCK_FOR_INSN (tail);
init_deps_global ();
/* Compute dependencies. */
- init_deps (&tmp_deps);
+ init_deps (&tmp_deps, false);
sched_analyze (&tmp_deps, head, tail);
free_deps (&tmp_deps);
}
else
/* Only recovery blocks can have their dependencies already calculated,
- and they always are single block ebbs. */
+ and they always are single block ebbs. */
gcc_assert (first_bb == last_bb);
/* Set priorities. */
/* Make ready list big enough to hold all the instructions from the ebb. */
sched_extend_ready_list (rgn_n_insns);
- schedule_block (&target_bb);
+ success = schedule_block (&target_bb, NULL);
+ gcc_assert (success || modulo_scheduling);
+
/* Free ready list. */
sched_finish_ready_list ();
/* We might pack all instructions into fewer blocks,
so we may made some of them empty. Can't assert (b == last_bb). */
-
+
/* Sanity check: verify that all region insns were scheduled. */
- gcc_assert (sched_rgn_n_insns == rgn_n_insns);
+ gcc_assert (modulo_scheduling || sched_rgn_n_insns == rgn_n_insns);
/* Free dependencies. */
sched_free_deps (current_sched_info->head, current_sched_info->tail, true);
delete_basic_block (last_bb->next_bb);
}
- return last_bb;
+ return success ? last_bb : NULL;
}
-/* The one entry point in this file. */
-
+/* Perform initializations before running schedule_ebbs or a single
+ schedule_ebb. */
void
-schedule_ebbs (void)
+schedule_ebbs_init (void)
{
- basic_block bb;
- int probability_cutoff;
- rtx tail;
-
- if (profile_info && flag_branch_probabilities)
- probability_cutoff = PARAM_VALUE (TRACER_MIN_BRANCH_PROBABILITY_FEEDBACK);
- else
- probability_cutoff = PARAM_VALUE (TRACER_MIN_BRANCH_PROBABILITY);
- probability_cutoff = REG_BR_PROB_BASE / 100 * probability_cutoff;
-
- /* Taking care of this degenerate case makes the rest of
- this code simpler. */
- if (n_basic_blocks == NUM_FIXED_BLOCKS)
- return;
-
/* Setup infos. */
{
memcpy (&ebb_common_sched_info, &haifa_common_sched_info,
/* Initialize DONT_CALC_DEPS and ebb-{start, end} markers. */
bitmap_initialize (&dont_calc_deps, 0);
bitmap_clear (&dont_calc_deps);
+}
+
+/* Perform cleanups after scheduling using schedules_ebbs or schedule_ebb. */
+void
+schedule_ebbs_finish (void)
+{
+ bitmap_clear (&dont_calc_deps);
+
+ /* Reposition the prologue and epilogue notes in case we moved the
+ prologue/epilogue insns. */
+ if (reload_completed)
+ reposition_prologue_and_epilogue_notes ();
+
+ haifa_sched_finish ();
+}
+
+/* The main entry point in this file. */
+
+void
+schedule_ebbs (void)
+{
+ basic_block bb;
+ int probability_cutoff;
+ rtx_insn *tail;
+
+ /* Taking care of this degenerate case makes the rest of
+ this code simpler. */
+ if (n_basic_blocks_for_fn (cfun) == NUM_FIXED_BLOCKS)
+ return;
+
+ if (profile_info && flag_branch_probabilities)
+ probability_cutoff = PARAM_VALUE (TRACER_MIN_BRANCH_PROBABILITY_FEEDBACK);
+ else
+ probability_cutoff = PARAM_VALUE (TRACER_MIN_BRANCH_PROBABILITY);
+ probability_cutoff = REG_BR_PROB_BASE / 100 * probability_cutoff;
+
+ schedule_ebbs_init ();
/* Schedule every region in the subroutine. */
- FOR_EACH_BB (bb)
+ FOR_EACH_BB_FN (bb, cfun)
{
- rtx head = BB_HEAD (bb);
+ rtx_insn *head = BB_HEAD (bb);
+
+ if (bb->flags & BB_DISABLE_SCHEDULE)
+ continue;
for (;;)
{
edge e;
- edge_iterator ei;
tail = BB_END (bb);
- if (bb->next_bb == EXIT_BLOCK_PTR
+ if (bb->next_bb == EXIT_BLOCK_PTR_FOR_FN (cfun)
|| LABEL_P (BB_HEAD (bb->next_bb)))
break;
- FOR_EACH_EDGE (e, ei, bb->succs)
- if ((e->flags & EDGE_FALLTHRU) != 0)
- break;
+ e = find_fallthru_edge (bb->succs);
if (! e)
break;
if (e->probability <= probability_cutoff)
break;
+ if (e->dest->flags & BB_DISABLE_SCHEDULE)
+ break;
bb = bb->next_bb;
}
- /* Blah. We should fix the rest of the code not to get confused by
- a note or two. */
- while (head != tail)
- {
- if (NOTE_P (head))
- head = NEXT_INSN (head);
- else if (NOTE_P (tail))
- tail = PREV_INSN (tail);
- else if (LABEL_P (head))
- head = NEXT_INSN (head);
- else
- break;
- }
-
- bb = schedule_ebb (head, tail);
+ bb = schedule_ebb (head, tail, false);
}
- bitmap_clear (&dont_calc_deps);
-
- /* Reposition the prologue and epilogue notes in case we moved the
- prologue/epilogue insns. */
- if (reload_completed)
- reposition_prologue_and_epilogue_notes ();
-
- haifa_sched_finish ();
+ schedule_ebbs_finish ();
}
/* INSN has been added to/removed from current ebb. */
static void
-ebb_add_remove_insn (rtx insn ATTRIBUTE_UNUSED, int remove_p)
+ebb_add_remove_insn (rtx_insn *insn ATTRIBUTE_UNUSED, int remove_p)
{
if (!remove_p)
rgn_n_insns++;
static void
ebb_add_block (basic_block bb, basic_block after)
{
- /* Recovery blocks are always bounded by BARRIERS,
+ /* Recovery blocks are always bounded by BARRIERS,
therefore, they always form single block EBB,
therefore, we can use rec->index to identify such EBBs. */
- if (after == EXIT_BLOCK_PTR)
+ if (after == EXIT_BLOCK_PTR_FOR_FN (cfun))
bitmap_set_bit (&dont_calc_deps, bb->index);
else if (after == last_bb)
last_bb = bb;
/* Return next block in ebb chain. For parameter meaning please refer to
sched-int.h: struct sched_info: advance_target_bb. */
static basic_block
-advance_target_bb (basic_block bb, rtx insn)
+advance_target_bb (basic_block bb, rtx_insn *insn)
{
if (insn)
{
gcc_assert (last_bb->index != bbi);
if (jump_bb_nexti == last_bb->index)
- last_bb = BASIC_BLOCK (jump_bbi);
+ last_bb = BASIC_BLOCK_FOR_FN (cfun, jump_bbi);
}
#endif /* INSN_SCHEDULING */