/* Instruction scheduling pass. Selective scheduler and pipeliner.
- Copyright (C) 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
+ Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011
+ Free Software Foundation, Inc.
This file is part of GCC.
#include "coretypes.h"
#include "tm.h"
#include "diagnostic-core.h"
-#include "toplev.h"
#include "rtl.h"
#include "tm_p.h"
#include "hard-reg-set.h"
#include "insn-config.h"
#include "insn-attr.h"
#include "except.h"
-#include "toplev.h"
#include "recog.h"
#include "params.h"
#include "target.h"
static void remove_empty_bb (basic_block, bool);
static void sel_merge_blocks (basic_block, basic_block);
static void sel_remove_loop_preheader (void);
+static bool bb_has_removable_jump_to_p (basic_block, basic_block);
static bool insn_is_the_only_one_in_bb_p (insn_t);
static void create_initial_data_sets (basic_block);
gcc_assert ((s != NULL && dc != NULL && tc != NULL)
|| (s == NULL && dc == NULL && tc == NULL));
- if (s != NULL)
- free (s);
+ free (s);
if (dc != NULL)
delete_deps_context (dc);
*pvect = NULL;
}
+/* Merge vector FROM to PVECT. */
+static void
+merge_history_vect (VEC (expr_history_def, heap) **pvect,
+ VEC (expr_history_def, heap) *from)
+{
+ expr_history_def *phist;
+ int i;
+
+ /* We keep this vector sorted. */
+ for (i = 0; VEC_iterate (expr_history_def, from, i, phist); i++)
+ insert_in_history_vect (pvect, phist->uid, phist->type,
+ phist->old_expr_vinsn, phist->new_expr_vinsn,
+ phist->spec_ds);
+}
/* Compare two vinsns as rhses if possible and as vinsns otherwise. */
bool
void
merge_expr_data (expr_t to, expr_t from, insn_t split_point)
{
- int i;
- expr_history_def *phist;
-
/* For now, we just set the spec of resulting expr to be minimum of the specs
of merged exprs. */
if (EXPR_SPEC (to) > EXPR_SPEC (from))
EXPR_ORIG_SCHED_CYCLE (to) = MIN (EXPR_ORIG_SCHED_CYCLE (to),
EXPR_ORIG_SCHED_CYCLE (from));
- /* We keep this vector sorted. */
- for (i = 0;
- VEC_iterate (expr_history_def, EXPR_HISTORY_OF_CHANGES (from),
- i, phist);
- i++)
- insert_in_history_vect (&EXPR_HISTORY_OF_CHANGES (to),
- phist->uid, phist->type,
- phist->old_expr_vinsn, phist->new_expr_vinsn,
- phist->spec_ds);
-
EXPR_WAS_SUBSTITUTED (to) |= EXPR_WAS_SUBSTITUTED (from);
EXPR_WAS_RENAMED (to) |= EXPR_WAS_RENAMED (from);
EXPR_CANT_MOVE (to) |= EXPR_CANT_MOVE (from);
+ merge_history_vect (&EXPR_HISTORY_OF_CHANGES (to),
+ EXPR_HISTORY_OF_CHANGES (from));
update_target_availability (to, from, split_point);
update_speculative_bits (to, from, split_point);
}
}
/* Leave in AVP only those expressions, which are present in AV,
- and return it. */
+ and return it, merging history expressions. */
void
-av_set_intersect (av_set_t *avp, av_set_t av)
+av_set_code_motion_filter (av_set_t *avp, av_set_t av)
{
av_set_iterator i;
- expr_t expr;
+ expr_t expr, expr2;
FOR_EACH_EXPR_1 (expr, i, avp)
- if (av_set_lookup (av, EXPR_VINSN (expr)) == NULL)
+ if ((expr2 = av_set_lookup (av, EXPR_VINSN (expr))) == NULL)
av_set_iter_remove (&i);
+ else
+ /* When updating av sets in bookkeeping blocks, we can add more insns
+ there which will be transformed but the upper av sets will not
+ reflect those transformations. We then fail to undo those
+ when searching for such insns. So merge the history saved
+ in the av set of the block we are processing. */
+ merge_history_vect (&EXPR_HISTORY_OF_CHANGES (expr),
+ EXPR_HISTORY_OF_CHANGES (expr2));
}
\f
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 (). */
maybe_tidy_empty_bb (basic_block bb)
{
basic_block succ_bb, pred_bb;
+ VEC (basic_block, heap) *dom_bbs;
edge e;
edge_iterator ei;
bool rescan_p;
succ_bb = single_succ (bb);
rescan_p = true;
pred_bb = NULL;
+ dom_bbs = NULL;
/* Redirect all non-fallthru edges to the next bb. */
while (rescan_p)
if (!(e->flags & EDGE_FALLTHRU))
{
/* We can not invalidate computed topological order by moving
- the edge destination block (E->SUCC) along a fallthru edge. */
+ the edge destination block (E->SUCC) along a fallthru edge.
+
+ We will update dominators here only when we'll get
+ an unreachable block when redirecting, otherwise
+ sel_redirect_edge_and_branch will take care of it. */
+ if (e->dest != bb
+ && single_pred_p (e->dest))
+ VEC_safe_push (basic_block, heap, dom_bbs, e->dest);
sel_redirect_edge_and_branch (e, succ_bb);
rescan_p = true;
break;
remove_empty_bb (bb, true);
}
+ if (!VEC_empty (basic_block, dom_bbs))
+ {
+ VEC_safe_push (basic_block, heap, dom_bbs, succ_bb);
+ iterate_fix_dominators (CDI_DOMINATORS, dom_bbs, false);
+ VEC_free (basic_block, heap, dom_bbs);
+ }
+
return true;
}
return changed;
/* Check if there is a unnecessary jump after insn left. */
- if (jump_leads_only_to_bb_p (BB_END (xbb), xbb->next_bb)
+ if (bb_has_removable_jump_to_p (xbb, xbb->next_bb)
&& INSN_SCHED_TIMES (BB_END (xbb)) == 0
&& !IN_CURRENT_FENCE_P (BB_END (xbb)))
{
/* And unconditional jump in previous basic block leads to
next basic block of XBB and this jump can be safely removed. */
&& in_current_region_p (xbb->prev_bb)
- && jump_leads_only_to_bb_p (BB_END (xbb->prev_bb), xbb->next_bb)
+ && bb_has_removable_jump_to_p (xbb->prev_bb, xbb->next_bb)
&& INSN_SCHED_TIMES (BB_END (xbb->prev_bb)) == 0
/* Also this jump is not at the scheduling boundary. */
&& !IN_CURRENT_FENCE_P (BB_END (xbb->prev_bb)))
#ifdef ENABLE_CHECKING
verify_backedges ();
+ verify_dominators (CDI_DOMINATORS);
#endif
return changed;
void
purge_empty_blocks (void)
{
- /* Do not attempt to delete preheader. */
- int i = sel_is_loop_preheader_p (BASIC_BLOCK (BB_TO_BLOCK (0))) ? 1 : 0;
+ int i;
- while (i < current_nr_blocks)
+ /* Do not attempt to delete the first basic block in the region. */
+ for (i = 1; i < current_nr_blocks; )
{
basic_block b = BASIC_BLOCK (BB_TO_BLOCK (i));
if (!JUMP_P (jump))
return NULL;
- if (any_uncondjump_p (jump))
- return single_succ (BLOCK_FOR_INSN (jump));
-
if (!any_condjump_p (jump))
return NULL;
bitmap_clear_bit (blocks_to_reschedule, idx);
if (remove_from_cfg_p)
- delete_and_free_basic_block (bb);
+ {
+ basic_block succ = single_succ (bb);
+ delete_and_free_basic_block (bb);
+ set_immediate_dominator (CDI_DOMINATORS, succ,
+ recompute_dominator (CDI_DOMINATORS, succ));
+ }
rgn_setup_region (CONTAINING_RGN (idx));
}
void
sel_redirect_edge_and_branch_force (edge e, basic_block to)
{
- basic_block jump_bb, src;
+ basic_block jump_bb, src, orig_dest = e->dest;
int prev_max_uid;
rtx jump;
- gcc_assert (!sel_bb_empty_p (e->src));
-
+ /* This function is now used only for bookkeeping code creation, where
+ we'll never get the single pred of orig_dest block and thus will not
+ hit unreachable blocks when updating dominator info. */
+ gcc_assert (!sel_bb_empty_p (e->src)
+ && !single_pred_p (orig_dest));
src = e->src;
prev_max_uid = get_max_uid ();
jump_bb = redirect_edge_and_branch_force (e, to);
jump = find_new_jump (src, jump_bb, prev_max_uid);
if (jump)
sel_init_new_insn (jump, INSN_INIT_TODO_LUID | INSN_INIT_TODO_SIMPLEJUMP);
+ set_immediate_dominator (CDI_DOMINATORS, to,
+ recompute_dominator (CDI_DOMINATORS, to));
+ set_immediate_dominator (CDI_DOMINATORS, orig_dest,
+ recompute_dominator (CDI_DOMINATORS, orig_dest));
}
/* A wrapper for redirect_edge_and_branch. Return TRUE if blocks connected by
sel_redirect_edge_and_branch (edge e, basic_block to)
{
bool latch_edge_p;
- basic_block src;
+ basic_block src, orig_dest = e->dest;
int prev_max_uid;
rtx jump;
edge redirected;
bool recompute_toporder_p = false;
+ bool maybe_unreachable = single_pred_p (orig_dest);
latch_edge_p = (pipelining_p
&& current_loop_nest
if (jump)
sel_init_new_insn (jump, INSN_INIT_TODO_LUID | INSN_INIT_TODO_SIMPLEJUMP);
+ /* Only update dominator info when we don't have unreachable blocks.
+ Otherwise we'll update in maybe_tidy_empty_bb. */
+ if (!maybe_unreachable)
+ {
+ set_immediate_dominator (CDI_DOMINATORS, to,
+ recompute_dominator (CDI_DOMINATORS, to));
+ set_immediate_dominator (CDI_DOMINATORS, orig_dest,
+ recompute_dominator (CDI_DOMINATORS, orig_dest));
+ }
return recompute_toporder_p;
}
NULL, /* add_remove_insn */
NULL, /* begin_schedule_ready */
+ NULL, /* begin_move_insn */
NULL, /* advance_target_bb */
SEL_SCHED | NEW_BBS
};
bbs_in_loop_rgns = NULL;
}
-/* Adds the preheader blocks from previous loop to current region taking
- it from LOOP_PREHEADER_BLOCKS (current_loop_nest).
+/* Add the preheader blocks from previous loop to current region taking
+ it from LOOP_PREHEADER_BLOCKS (current_loop_nest) and record them in *BBS.
This function is only used with -fsel-sched-pipelining-outer-loops. */
void
-sel_add_loop_preheaders (void)
+sel_add_loop_preheaders (bb_vec_t *bbs)
{
int i;
basic_block bb;
VEC_iterate (basic_block, preheader_blocks, i, bb);
i++)
{
+ VEC_safe_push (basic_block, heap, *bbs, bb);
VEC_safe_push (basic_block, heap, last_added_blocks, bb);
sel_add_bb (bb);
}
return false;
}
-/* Checks whether JUMP leads to basic block DEST_BB and no other blocks. */
-bool
-jump_leads_only_to_bb_p (insn_t jump, basic_block dest_bb)
+/* Check whether JUMP_BB ends with a jump insn that leads only to DEST_BB and
+ can be removed, making the corresponding edge fallthrough (assuming that
+ all basic blocks between JUMP_BB and DEST_BB are empty). */
+static bool
+bb_has_removable_jump_to_p (basic_block jump_bb, basic_block dest_bb)
{
- basic_block jump_bb = BLOCK_FOR_INSN (jump);
-
- /* It is not jump, jump with side-effects or jump can lead to several
- basic blocks. */
- if (!onlyjump_p (jump)
- || !any_uncondjump_p (jump))
+ if (!onlyjump_p (BB_END (jump_bb))
+ || tablejump_p (BB_END (jump_bb), NULL, NULL))
return false;
/* Several outgoing edges, abnormal edge or destination of jump is
not DEST_BB. */
if (EDGE_COUNT (jump_bb->succs) != 1
- || EDGE_SUCC (jump_bb, 0)->flags & EDGE_ABNORMAL
+ || EDGE_SUCC (jump_bb, 0)->flags & (EDGE_ABNORMAL | EDGE_CROSSING)
|| EDGE_SUCC (jump_bb, 0)->dest != dest_bb)
return false;
basic block if it becomes empty. */
if (next_bb->prev_bb == prev_bb
&& prev_bb != ENTRY_BLOCK_PTR
- && jump_leads_only_to_bb_p (BB_END (prev_bb), next_bb))
+ && bb_has_removable_jump_to_p (prev_bb, next_bb))
{
redirect_edge_and_branch (EDGE_SUCC (prev_bb, 0), next_bb);
if (BB_END (prev_bb) == bb_note (prev_bb))
free_data_sets (prev_bb);
}
+
+ set_immediate_dominator (CDI_DOMINATORS, next_bb,
+ recompute_dominator (CDI_DOMINATORS,
+ next_bb));
}
}
VEC_free (basic_block, heap, preheader_blocks);
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