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+/* Control flow graph manipulation code for GNU compiler.
+ Copyright (C) 1987-2014 Free Software Foundation, Inc.
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 3, or (at your option) any later
+version.
+
+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with GCC; see the file COPYING3. If not see
+<http://www.gnu.org/licenses/>. */
+
+/* This file contains low level functions to manipulate the CFG and analyze it
+ that are aware of the RTL intermediate language.
+
+ Available functionality:
+ - Basic CFG/RTL manipulation API documented in cfghooks.h
+ - CFG-aware instruction chain manipulation
+ delete_insn, delete_insn_chain
+ - Edge splitting and committing to edges
+ insert_insn_on_edge, commit_edge_insertions
+ - CFG updating after insn simplification
+ purge_dead_edges, purge_all_dead_edges
+ - CFG fixing after coarse manipulation
+ fixup_abnormal_edges
+
+ Functions not supposed for generic use:
+ - Infrastructure to determine quickly basic block for insn
+ compute_bb_for_insn, update_bb_for_insn, set_block_for_insn,
+ - Edge redirection with updating and optimizing of insn chain
+ block_label, tidy_fallthru_edge, force_nonfallthru */
+
+#include "config.h"
+#include "system.h"
+#include "coretypes.h"
+#include "tm.h"
+#include "tree.h"
+#include "hard-reg-set.h"
+#include "basic-block.h"
+#include "bb-reorder.h"
+#include "regs.h"
+#include "flags.h"
+#include "function.h"
+#include "except.h"
+#include "rtl-error.h"
+#include "tm_p.h"
+#include "obstack.h"
+#include "insn-attr.h"
+#include "insn-config.h"
+#include "expr.h"
+#include "target.h"
+#include "common/common-target.h"
+#include "cfgloop.h"
+#include "ggc.h"
+#include "tree-pass.h"
+#include "df.h"
+
+/* Holds the interesting leading and trailing notes for the function.
+ Only applicable if the CFG is in cfglayout mode. */
+static GTY(()) rtx cfg_layout_function_footer;
+static GTY(()) rtx cfg_layout_function_header;
+
+static rtx skip_insns_after_block (basic_block);
+static void record_effective_endpoints (void);
+static rtx label_for_bb (basic_block);
+static void fixup_reorder_chain (void);
+
+void verify_insn_chain (void);
+static void fixup_fallthru_exit_predecessor (void);
+static int can_delete_note_p (const_rtx);
+static int can_delete_label_p (const_rtx);
+static basic_block rtl_split_edge (edge);
+static bool rtl_move_block_after (basic_block, basic_block);
+static int rtl_verify_flow_info (void);
+static basic_block cfg_layout_split_block (basic_block, void *);
+static edge cfg_layout_redirect_edge_and_branch (edge, basic_block);
+static basic_block cfg_layout_redirect_edge_and_branch_force (edge, basic_block);
+static void cfg_layout_delete_block (basic_block);
+static void rtl_delete_block (basic_block);
+static basic_block rtl_redirect_edge_and_branch_force (edge, basic_block);
+static edge rtl_redirect_edge_and_branch (edge, basic_block);
+static basic_block rtl_split_block (basic_block, void *);
+static void rtl_dump_bb (FILE *, basic_block, int, int);
+static int rtl_verify_flow_info_1 (void);
+static void rtl_make_forwarder_block (edge);
+
+/* Return true if NOTE is not one of the ones that must be kept paired,
+ so that we may simply delete it. */
+
+static int
+can_delete_note_p (const_rtx note)
+{
+ switch (NOTE_KIND (note))
+ {
+ case NOTE_INSN_DELETED:
+ case NOTE_INSN_BASIC_BLOCK:
+ case NOTE_INSN_EPILOGUE_BEG:
+ return true;
+
+ default:
+ return false;
+ }
+}
+
+/* True if a given label can be deleted. */
+
+static int
+can_delete_label_p (const_rtx label)
+{
+ return (!LABEL_PRESERVE_P (label)
+ /* User declared labels must be preserved. */
+ && LABEL_NAME (label) == 0
+ && !in_expr_list_p (forced_labels, label));
+}
+
+/* Delete INSN by patching it out. */
+
+void
+delete_insn (rtx insn)
+{
+ rtx note;
+ bool really_delete = true;
+
+ if (LABEL_P (insn))
+ {
+ /* Some labels can't be directly removed from the INSN chain, as they
+ might be references via variables, constant pool etc.
+ Convert them to the special NOTE_INSN_DELETED_LABEL note. */
+ if (! can_delete_label_p (insn))
+ {
+ const char *name = LABEL_NAME (insn);
+ basic_block bb = BLOCK_FOR_INSN (insn);
+ rtx bb_note = NEXT_INSN (insn);
+
+ really_delete = false;
+ PUT_CODE (insn, NOTE);
+ NOTE_KIND (insn) = NOTE_INSN_DELETED_LABEL;
+ NOTE_DELETED_LABEL_NAME (insn) = name;
+
+ /* If the note following the label starts a basic block, and the
+ label is a member of the same basic block, interchange the two. */
+ if (bb_note != NULL_RTX
+ && NOTE_INSN_BASIC_BLOCK_P (bb_note)
+ && bb != NULL
+ && bb == BLOCK_FOR_INSN (bb_note))
+ {
+ reorder_insns_nobb (insn, insn, bb_note);
+ BB_HEAD (bb) = bb_note;
+ if (BB_END (bb) == bb_note)
+ BB_END (bb) = insn;
+ }
+ }
+
+ remove_node_from_expr_list (insn, &nonlocal_goto_handler_labels);
+ }
+
+ if (really_delete)
+ {
+ /* If this insn has already been deleted, something is very wrong. */
+ gcc_assert (!INSN_DELETED_P (insn));
+ if (INSN_P (insn))
+ df_insn_delete (insn);
+ remove_insn (insn);
+ INSN_DELETED_P (insn) = 1;
+ }
+
+ /* If deleting a jump, decrement the use count of the label. Deleting
+ the label itself should happen in the normal course of block merging. */
+ if (JUMP_P (insn))
+ {
+ if (JUMP_LABEL (insn)
+ && LABEL_P (JUMP_LABEL (insn)))
+ LABEL_NUSES (JUMP_LABEL (insn))--;
+
+ /* If there are more targets, remove them too. */
+ while ((note
+ = find_reg_note (insn, REG_LABEL_TARGET, NULL_RTX)) != NULL_RTX
+ && LABEL_P (XEXP (note, 0)))
+ {
+ LABEL_NUSES (XEXP (note, 0))--;
+ remove_note (insn, note);
+ }
+ }
+
+ /* Also if deleting any insn that references a label as an operand. */
+ while ((note = find_reg_note (insn, REG_LABEL_OPERAND, NULL_RTX)) != NULL_RTX
+ && LABEL_P (XEXP (note, 0)))
+ {
+ LABEL_NUSES (XEXP (note, 0))--;
+ remove_note (insn, note);
+ }
+
+ if (JUMP_TABLE_DATA_P (insn))
+ {
+ rtx pat = PATTERN (insn);
+ int diff_vec_p = GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC;
+ int len = XVECLEN (pat, diff_vec_p);
+ int i;
+
+ for (i = 0; i < len; i++)
+ {
+ rtx label = XEXP (XVECEXP (pat, diff_vec_p, i), 0);
+
+ /* When deleting code in bulk (e.g. removing many unreachable
+ blocks) we can delete a label that's a target of the vector
+ before deleting the vector itself. */
+ if (!NOTE_P (label))
+ LABEL_NUSES (label)--;
+ }
+ }
+}
+
+/* Like delete_insn but also purge dead edges from BB. */
+
+void
+delete_insn_and_edges (rtx insn)
+{
+ bool purge = false;
+
+ if (INSN_P (insn)
+ && BLOCK_FOR_INSN (insn)
+ && BB_END (BLOCK_FOR_INSN (insn)) == insn)
+ purge = true;
+ delete_insn (insn);
+ if (purge)
+ purge_dead_edges (BLOCK_FOR_INSN (insn));
+}
+
+/* Unlink a chain of insns between START and FINISH, leaving notes
+ that must be paired. If CLEAR_BB is true, we set bb field for
+ insns that cannot be removed to NULL. */
+
+void
+delete_insn_chain (rtx start, rtx finish, bool clear_bb)
+{
+ rtx prev, current;
+
+ /* Unchain the insns one by one. It would be quicker to delete all of these
+ with a single unchaining, rather than one at a time, but we need to keep
+ the NOTE's. */
+ current = finish;
+ while (1)
+ {
+ prev = PREV_INSN (current);
+ if (NOTE_P (current) && !can_delete_note_p (current))
+ ;
+ else
+ delete_insn (current);
+
+ if (clear_bb && !INSN_DELETED_P (current))
+ set_block_for_insn (current, NULL);
+
+ if (current == start)
+ break;
+ current = prev;
+ }
+}
+
+/* Create a new basic block consisting of the instructions between HEAD and END
+ inclusive. This function is designed to allow fast BB construction - reuses
+ the note and basic block struct in BB_NOTE, if any and do not grow
+ BASIC_BLOCK chain and should be used directly only by CFG construction code.
+ END can be NULL in to create new empty basic block before HEAD. Both END
+ and HEAD can be NULL to create basic block at the end of INSN chain.
+ AFTER is the basic block we should be put after. */
+
+basic_block
+create_basic_block_structure (rtx head, rtx end, rtx bb_note, basic_block after)
+{
+ basic_block bb;
+
+ if (bb_note
+ && (bb = NOTE_BASIC_BLOCK (bb_note)) != NULL
+ && bb->aux == NULL)
+ {
+ /* If we found an existing note, thread it back onto the chain. */
+
+ rtx after;
+
+ if (LABEL_P (head))
+ after = head;
+ else
+ {
+ after = PREV_INSN (head);
+ head = bb_note;
+ }
+
+ if (after != bb_note && NEXT_INSN (after) != bb_note)
+ reorder_insns_nobb (bb_note, bb_note, after);
+ }
+ else
+ {
+ /* Otherwise we must create a note and a basic block structure. */
+
+ bb = alloc_block ();
+
+ init_rtl_bb_info (bb);
+ if (!head && !end)
+ head = end = bb_note
+ = emit_note_after (NOTE_INSN_BASIC_BLOCK, get_last_insn ());
+ else if (LABEL_P (head) && end)
+ {
+ bb_note = emit_note_after (NOTE_INSN_BASIC_BLOCK, head);
+ if (head == end)
+ end = bb_note;
+ }
+ else
+ {
+ bb_note = emit_note_before (NOTE_INSN_BASIC_BLOCK, head);
+ head = bb_note;
+ if (!end)
+ end = head;
+ }
+
+ NOTE_BASIC_BLOCK (bb_note) = bb;
+ }
+
+ /* Always include the bb note in the block. */
+ if (NEXT_INSN (end) == bb_note)
+ end = bb_note;
+
+ BB_HEAD (bb) = head;
+ BB_END (bb) = end;
+ bb->index = last_basic_block_for_fn (cfun)++;
+ bb->flags = BB_NEW | BB_RTL;
+ link_block (bb, after);
+ SET_BASIC_BLOCK_FOR_FN (cfun, bb->index, bb);
+ df_bb_refs_record (bb->index, false);
+ update_bb_for_insn (bb);
+ BB_SET_PARTITION (bb, BB_UNPARTITIONED);
+
+ /* Tag the block so that we know it has been used when considering
+ other basic block notes. */
+ bb->aux = bb;
+
+ return bb;
+}
+
+/* Create new basic block consisting of instructions in between HEAD and END
+ and place it to the BB chain after block AFTER. END can be NULL to
+ create a new empty basic block before HEAD. Both END and HEAD can be
+ NULL to create basic block at the end of INSN chain. */
+
+static basic_block
+rtl_create_basic_block (void *headp, void *endp, basic_block after)
+{
+ rtx head = (rtx) headp, end = (rtx) endp;
+ basic_block bb;
+
+ /* Grow the basic block array if needed. */
+ if ((size_t) last_basic_block_for_fn (cfun)
+ >= basic_block_info_for_fn (cfun)->length ())
+ {
+ size_t new_size =
+ (last_basic_block_for_fn (cfun)
+ + (last_basic_block_for_fn (cfun) + 3) / 4);
+ vec_safe_grow_cleared (basic_block_info_for_fn (cfun), new_size);
+ }
+
+ n_basic_blocks_for_fn (cfun)++;
+
+ bb = create_basic_block_structure (head, end, NULL, after);
+ bb->aux = NULL;
+ return bb;
+}
+
+static basic_block
+cfg_layout_create_basic_block (void *head, void *end, basic_block after)
+{
+ basic_block newbb = rtl_create_basic_block (head, end, after);
+
+ return newbb;
+}
+
+/* Delete the insns in a (non-live) block. We physically delete every
+ non-deleted-note insn, and update the flow graph appropriately.
+
+ Return nonzero if we deleted an exception handler. */
+
+/* ??? Preserving all such notes strikes me as wrong. It would be nice
+ to post-process the stream to remove empty blocks, loops, ranges, etc. */
+
+static void
+rtl_delete_block (basic_block b)
+{
+ rtx insn, end;
+
+ /* If the head of this block is a CODE_LABEL, then it might be the
+ label for an exception handler which can't be reached. We need
+ to remove the label from the exception_handler_label list. */
+ insn = BB_HEAD (b);
+
+ end = get_last_bb_insn (b);
+
+ /* Selectively delete the entire chain. */
+ BB_HEAD (b) = NULL;
+ delete_insn_chain (insn, end, true);
+
+
+ if (dump_file)
+ fprintf (dump_file, "deleting block %d\n", b->index);
+ df_bb_delete (b->index);
+}
+
+/* Records the basic block struct in BLOCK_FOR_INSN for every insn. */
+
+void
+compute_bb_for_insn (void)
+{
+ basic_block bb;
+
+ FOR_EACH_BB_FN (bb, cfun)
+ {
+ rtx end = BB_END (bb);
+ rtx insn;
+
+ for (insn = BB_HEAD (bb); ; insn = NEXT_INSN (insn))
+ {
+ BLOCK_FOR_INSN (insn) = bb;
+ if (insn == end)
+ break;
+ }
+ }
+}
+
+/* Release the basic_block_for_insn array. */
+
+unsigned int
+free_bb_for_insn (void)
+{
+ rtx insn;
+ for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
+ if (!BARRIER_P (insn))
+ BLOCK_FOR_INSN (insn) = NULL;
+ return 0;
+}
+
+static unsigned int
+rest_of_pass_free_cfg (void)
+{
+#ifdef DELAY_SLOTS
+ /* The resource.c machinery uses DF but the CFG isn't guaranteed to be
+ valid at that point so it would be too late to call df_analyze. */
+ if (optimize > 0 && flag_delayed_branch)
+ {
+ df_note_add_problem ();
+ df_analyze ();
+ }
+#endif
+
+ if (crtl->has_bb_partition)
+ insert_section_boundary_note ();
+
+ free_bb_for_insn ();
+ return 0;
+}
+
+namespace {
+
+const pass_data pass_data_free_cfg =
+{
+ RTL_PASS, /* type */
+ "*free_cfg", /* name */
+ OPTGROUP_NONE, /* optinfo_flags */
+ false, /* has_gate */
+ true, /* has_execute */
+ TV_NONE, /* tv_id */
+ 0, /* properties_required */
+ 0, /* properties_provided */
+ PROP_cfg, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ 0, /* todo_flags_finish */
+};
+
+class pass_free_cfg : public rtl_opt_pass
+{
+public:
+ pass_free_cfg (gcc::context *ctxt)
+ : rtl_opt_pass (pass_data_free_cfg, ctxt)
+ {}
+
+ /* opt_pass methods: */
+ unsigned int execute () { return rest_of_pass_free_cfg (); }
+
+}; // class pass_free_cfg
+
+} // anon namespace
+
+rtl_opt_pass *
+make_pass_free_cfg (gcc::context *ctxt)
+{
+ return new pass_free_cfg (ctxt);
+}
+
+/* Return RTX to emit after when we want to emit code on the entry of function. */
+rtx
+entry_of_function (void)
+{
+ return (n_basic_blocks_for_fn (cfun) > NUM_FIXED_BLOCKS ?
+ BB_HEAD (ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb) : get_insns ());
+}
+
+/* Emit INSN at the entry point of the function, ensuring that it is only
+ executed once per function. */
+void
+emit_insn_at_entry (rtx insn)
+{
+ edge_iterator ei = ei_start (ENTRY_BLOCK_PTR_FOR_FN (cfun)->succs);
+ edge e = ei_safe_edge (ei);
+ gcc_assert (e->flags & EDGE_FALLTHRU);
+
+ insert_insn_on_edge (insn, e);
+ commit_edge_insertions ();
+}
+
+/* Update BLOCK_FOR_INSN of insns between BEGIN and END
+ (or BARRIER if found) and notify df of the bb change.
+ The insn chain range is inclusive
+ (i.e. both BEGIN and END will be updated. */
+
+static void
+update_bb_for_insn_chain (rtx begin, rtx end, basic_block bb)
+{
+ rtx insn;
+
+ end = NEXT_INSN (end);
+ for (insn = begin; insn != end; insn = NEXT_INSN (insn))
+ if (!BARRIER_P (insn))
+ df_insn_change_bb (insn, bb);
+}
+
+/* Update BLOCK_FOR_INSN of insns in BB to BB,
+ and notify df of the change. */
+
+void
+update_bb_for_insn (basic_block bb)
+{
+ update_bb_for_insn_chain (BB_HEAD (bb), BB_END (bb), bb);
+}
+
+
+/* Like active_insn_p, except keep the return value clobber around
+ even after reload. */
+
+static bool
+flow_active_insn_p (const_rtx insn)
+{
+ if (active_insn_p (insn))
+ return true;
+
+ /* A clobber of the function return value exists for buggy
+ programs that fail to return a value. Its effect is to
+ keep the return value from being live across the entire
+ function. If we allow it to be skipped, we introduce the
+ possibility for register lifetime confusion. */
+ if (GET_CODE (PATTERN (insn)) == CLOBBER
+ && REG_P (XEXP (PATTERN (insn), 0))
+ && REG_FUNCTION_VALUE_P (XEXP (PATTERN (insn), 0)))
+ return true;
+
+ return false;
+}
+
+/* Return true if the block has no effect and only forwards control flow to
+ its single destination. */
+
+bool
+contains_no_active_insn_p (const_basic_block bb)
+{
+ rtx insn;
+
+ if (bb == EXIT_BLOCK_PTR_FOR_FN (cfun) || bb == ENTRY_BLOCK_PTR_FOR_FN (cfun)
+ || !single_succ_p (bb))
+ return false;
+
+ for (insn = BB_HEAD (bb); insn != BB_END (bb); insn = NEXT_INSN (insn))
+ if (INSN_P (insn) && flow_active_insn_p (insn))
+ return false;
+
+ return (!INSN_P (insn)
+ || (JUMP_P (insn) && simplejump_p (insn))
+ || !flow_active_insn_p (insn));
+}
+
+/* Likewise, but protect loop latches, headers and preheaders. */
+/* FIXME: Make this a cfg hook. */
+
+bool
+forwarder_block_p (const_basic_block bb)
+{
+ if (!contains_no_active_insn_p (bb))
+ return false;
+
+ /* Protect loop latches, headers and preheaders. */
+ if (current_loops)
+ {
+ basic_block dest;
+ if (bb->loop_father->header == bb)
+ return false;
+ dest = EDGE_SUCC (bb, 0)->dest;
+ if (dest->loop_father->header == dest)
+ return false;
+ }
+
+ return true;
+}
+
+/* Return nonzero if we can reach target from src by falling through. */
+/* FIXME: Make this a cfg hook, the result is only valid in cfgrtl mode. */
+
+bool
+can_fallthru (basic_block src, basic_block target)
+{
+ rtx insn = BB_END (src);
+ rtx insn2;
+ edge e;
+ edge_iterator ei;
+
+ if (target == EXIT_BLOCK_PTR_FOR_FN (cfun))
+ return true;
+ if (src->next_bb != target)
+ return false;
+
+ /* ??? Later we may add code to move jump tables offline. */
+ if (tablejump_p (insn, NULL, NULL))
+ return false;
+
+ FOR_EACH_EDGE (e, ei, src->succs)
+ if (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun)
+ && e->flags & EDGE_FALLTHRU)
+ return false;
+
+ insn2 = BB_HEAD (target);
+ if (!active_insn_p (insn2))
+ insn2 = next_active_insn (insn2);
+
+ return next_active_insn (insn) == insn2;
+}
+
+/* Return nonzero if we could reach target from src by falling through,
+ if the target was made adjacent. If we already have a fall-through
+ edge to the exit block, we can't do that. */
+static bool
+could_fall_through (basic_block src, basic_block target)
+{
+ edge e;
+ edge_iterator ei;
+
+ if (target == EXIT_BLOCK_PTR_FOR_FN (cfun))
+ return true;
+ FOR_EACH_EDGE (e, ei, src->succs)
+ if (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun)
+ && e->flags & EDGE_FALLTHRU)
+ return 0;
+ return true;
+}
+
+/* Return the NOTE_INSN_BASIC_BLOCK of BB. */
+rtx
+bb_note (basic_block bb)
+{
+ rtx note;
+
+ note = BB_HEAD (bb);
+ if (LABEL_P (note))
+ note = NEXT_INSN (note);
+
+ gcc_assert (NOTE_INSN_BASIC_BLOCK_P (note));
+ return note;
+}
+
+/* Return the INSN immediately following the NOTE_INSN_BASIC_BLOCK
+ note associated with the BLOCK. */
+
+static rtx
+first_insn_after_basic_block_note (basic_block block)
+{
+ rtx insn;
+
+ /* Get the first instruction in the block. */
+ insn = BB_HEAD (block);
+
+ if (insn == NULL_RTX)
+ return NULL_RTX;
+ if (LABEL_P (insn))
+ insn = NEXT_INSN (insn);
+ gcc_assert (NOTE_INSN_BASIC_BLOCK_P (insn));
+
+ return NEXT_INSN (insn);
+}
+
+/* Creates a new basic block just after basic block B by splitting
+ everything after specified instruction I. */
+
+static basic_block
+rtl_split_block (basic_block bb, void *insnp)
+{
+ basic_block new_bb;
+ rtx insn = (rtx) insnp;
+ edge e;
+ edge_iterator ei;
+
+ if (!insn)
+ {
+ insn = first_insn_after_basic_block_note (bb);
+
+ if (insn)
+ {
+ rtx next = insn;
+
+ insn = PREV_INSN (insn);
+
+ /* If the block contains only debug insns, insn would have
+ been NULL in a non-debug compilation, and then we'd end
+ up emitting a DELETED note. For -fcompare-debug
+ stability, emit the note too. */
+ if (insn != BB_END (bb)
+ && DEBUG_INSN_P (next)
+ && DEBUG_INSN_P (BB_END (bb)))
+ {
+ while (next != BB_END (bb) && DEBUG_INSN_P (next))
+ next = NEXT_INSN (next);
+
+ if (next == BB_END (bb))
+ emit_note_after (NOTE_INSN_DELETED, next);
+ }
+ }
+ else
+ insn = get_last_insn ();
+ }
+
+ /* We probably should check type of the insn so that we do not create
+ inconsistent cfg. It is checked in verify_flow_info anyway, so do not
+ bother. */
+ if (insn == BB_END (bb))
+ emit_note_after (NOTE_INSN_DELETED, insn);
+
+ /* Create the new basic block. */
+ new_bb = create_basic_block (NEXT_INSN (insn), BB_END (bb), bb);
+ BB_COPY_PARTITION (new_bb, bb);
+ BB_END (bb) = insn;
+
+ /* Redirect the outgoing edges. */
+ new_bb->succs = bb->succs;
+ bb->succs = NULL;
+ FOR_EACH_EDGE (e, ei, new_bb->succs)
+ e->src = new_bb;
+
+ /* The new block starts off being dirty. */
+ df_set_bb_dirty (bb);
+ return new_bb;
+}
+
+/* Return true if the single edge between blocks A and B is the only place
+ in RTL which holds some unique locus. */
+
+static bool
+unique_locus_on_edge_between_p (basic_block a, basic_block b)
+{
+ const location_t goto_locus = EDGE_SUCC (a, 0)->goto_locus;
+ rtx insn, end;
+
+ if (LOCATION_LOCUS (goto_locus) == UNKNOWN_LOCATION)
+ return false;
+
+ /* First scan block A backward. */
+ insn = BB_END (a);
+ end = PREV_INSN (BB_HEAD (a));
+ while (insn != end && (!NONDEBUG_INSN_P (insn) || !INSN_HAS_LOCATION (insn)))
+ insn = PREV_INSN (insn);
+
+ if (insn != end && INSN_LOCATION (insn) == goto_locus)
+ return false;
+
+ /* Then scan block B forward. */
+ insn = BB_HEAD (b);
+ if (insn)
+ {
+ end = NEXT_INSN (BB_END (b));
+ while (insn != end && !NONDEBUG_INSN_P (insn))
+ insn = NEXT_INSN (insn);
+
+ if (insn != end && INSN_HAS_LOCATION (insn)
+ && INSN_LOCATION (insn) == goto_locus)
+ return false;
+ }
+
+ return true;
+}
+
+/* If the single edge between blocks A and B is the only place in RTL which
+ holds some unique locus, emit a nop with that locus between the blocks. */
+
+static void
+emit_nop_for_unique_locus_between (basic_block a, basic_block b)
+{
+ if (!unique_locus_on_edge_between_p (a, b))
+ return;
+
+ BB_END (a) = emit_insn_after_noloc (gen_nop (), BB_END (a), a);
+ INSN_LOCATION (BB_END (a)) = EDGE_SUCC (a, 0)->goto_locus;
+}
+
+/* Blocks A and B are to be merged into a single block A. The insns
+ are already contiguous. */
+
+static void
+rtl_merge_blocks (basic_block a, basic_block b)
+{
+ rtx b_head = BB_HEAD (b), b_end = BB_END (b), a_end = BB_END (a);
+ rtx del_first = NULL_RTX, del_last = NULL_RTX;
+ rtx b_debug_start = b_end, b_debug_end = b_end;
+ bool forwarder_p = (b->flags & BB_FORWARDER_BLOCK) != 0;
+ int b_empty = 0;
+
+ if (dump_file)
+ fprintf (dump_file, "Merging block %d into block %d...\n", b->index,
+ a->index);
+
+ while (DEBUG_INSN_P (b_end))
+ b_end = PREV_INSN (b_debug_start = b_end);
+
+ /* If there was a CODE_LABEL beginning B, delete it. */
+ if (LABEL_P (b_head))
+ {
+ /* Detect basic blocks with nothing but a label. This can happen
+ in particular at the end of a function. */
+ if (b_head == b_end)
+ b_empty = 1;
+
+ del_first = del_last = b_head;
+ b_head = NEXT_INSN (b_head);
+ }
+
+ /* Delete the basic block note and handle blocks containing just that
+ note. */
+ if (NOTE_INSN_BASIC_BLOCK_P (b_head))
+ {
+ if (b_head == b_end)
+ b_empty = 1;
+ if (! del_last)
+ del_first = b_head;
+
+ del_last = b_head;
+ b_head = NEXT_INSN (b_head);
+ }
+
+ /* If there was a jump out of A, delete it. */
+ if (JUMP_P (a_end))
+ {
+ rtx prev;
+
+ for (prev = PREV_INSN (a_end); ; prev = PREV_INSN (prev))
+ if (!NOTE_P (prev)
+ || NOTE_INSN_BASIC_BLOCK_P (prev)
+ || prev == BB_HEAD (a))
+ break;
+
+ del_first = a_end;
+
+#ifdef HAVE_cc0
+ /* If this was a conditional jump, we need to also delete
+ the insn that set cc0. */
+ if (only_sets_cc0_p (prev))
+ {
+ rtx tmp = prev;
+
+ prev = prev_nonnote_insn (prev);
+ if (!prev)
+ prev = BB_HEAD (a);
+ del_first = tmp;
+ }
+#endif
+
+ a_end = PREV_INSN (del_first);
+ }
+ else if (BARRIER_P (NEXT_INSN (a_end)))
+ del_first = NEXT_INSN (a_end);
+
+ /* Delete everything marked above as well as crap that might be
+ hanging out between the two blocks. */
+ BB_END (a) = a_end;
+ BB_HEAD (b) = b_empty ? NULL_RTX : b_head;
+ delete_insn_chain (del_first, del_last, true);
+
+ /* When not optimizing CFG and the edge is the only place in RTL which holds
+ some unique locus, emit a nop with that locus in between. */
+ if (!optimize)
+ {
+ emit_nop_for_unique_locus_between (a, b);
+ a_end = BB_END (a);
+ }
+
+ /* Reassociate the insns of B with A. */
+ if (!b_empty)
+ {
+ update_bb_for_insn_chain (a_end, b_debug_end, a);
+
+ BB_END (a) = b_debug_end;
+ BB_HEAD (b) = NULL_RTX;
+ }
+ else if (b_end != b_debug_end)
+ {
+ /* Move any deleted labels and other notes between the end of A
+ and the debug insns that make up B after the debug insns,
+ bringing the debug insns into A while keeping the notes after
+ the end of A. */
+ if (NEXT_INSN (a_end) != b_debug_start)
+ reorder_insns_nobb (NEXT_INSN (a_end), PREV_INSN (b_debug_start),
+ b_debug_end);
+ update_bb_for_insn_chain (b_debug_start, b_debug_end, a);
+ BB_END (a) = b_debug_end;
+ }
+
+ df_bb_delete (b->index);
+
+ /* If B was a forwarder block, propagate the locus on the edge. */
+ if (forwarder_p
+ && LOCATION_LOCUS (EDGE_SUCC (b, 0)->goto_locus) == UNKNOWN_LOCATION)
+ EDGE_SUCC (b, 0)->goto_locus = EDGE_SUCC (a, 0)->goto_locus;
+
+ if (dump_file)
+ fprintf (dump_file, "Merged blocks %d and %d.\n", a->index, b->index);
+}
+
+
+/* Return true when block A and B can be merged. */
+
+static bool
+rtl_can_merge_blocks (basic_block a, basic_block b)
+{
+ /* If we are partitioning hot/cold basic blocks, we don't want to
+ mess up unconditional or indirect jumps that cross between hot
+ and cold sections.
+
+ Basic block partitioning may result in some jumps that appear to
+ be optimizable (or blocks that appear to be mergeable), but which really
+ must be left untouched (they are required to make it safely across
+ partition boundaries). See the comments at the top of
+ bb-reorder.c:partition_hot_cold_basic_blocks for complete details. */
+
+ if (BB_PARTITION (a) != BB_PARTITION (b))
+ return false;
+
+ /* Protect the loop latches. */
+ if (current_loops && b->loop_father->latch == b)
+ return false;
+
+ /* There must be exactly one edge in between the blocks. */
+ return (single_succ_p (a)
+ && single_succ (a) == b
+ && single_pred_p (b)
+ && a != b
+ /* Must be simple edge. */
+ && !(single_succ_edge (a)->flags & EDGE_COMPLEX)
+ && a->next_bb == b
+ && a != ENTRY_BLOCK_PTR_FOR_FN (cfun)
+ && b != EXIT_BLOCK_PTR_FOR_FN (cfun)
+ /* If the jump insn has side effects,
+ we can't kill the edge. */
+ && (!JUMP_P (BB_END (a))
+ || (reload_completed
+ ? simplejump_p (BB_END (a)) : onlyjump_p (BB_END (a)))));
+}
+
+/* Return the label in the head of basic block BLOCK. Create one if it doesn't
+ exist. */
+
+rtx
+block_label (basic_block block)
+{
+ if (block == EXIT_BLOCK_PTR_FOR_FN (cfun))
+ return NULL_RTX;
+
+ if (!LABEL_P (BB_HEAD (block)))
+ {
+ BB_HEAD (block) = emit_label_before (gen_label_rtx (), BB_HEAD (block));
+ }
+
+ return BB_HEAD (block);
+}
+
+/* Attempt to perform edge redirection by replacing possibly complex jump
+ instruction by unconditional jump or removing jump completely. This can
+ apply only if all edges now point to the same block. The parameters and
+ return values are equivalent to redirect_edge_and_branch. */
+
+edge
+try_redirect_by_replacing_jump (edge e, basic_block target, bool in_cfglayout)
+{
+ basic_block src = e->src;
+ rtx insn = BB_END (src), kill_from;
+ rtx set;
+ int fallthru = 0;
+
+ /* If we are partitioning hot/cold basic blocks, we don't want to
+ mess up unconditional or indirect jumps that cross between hot
+ and cold sections.
+
+ Basic block partitioning may result in some jumps that appear to
+ be optimizable (or blocks that appear to be mergeable), but which really
+ must be left untouched (they are required to make it safely across
+ partition boundaries). See the comments at the top of
+ bb-reorder.c:partition_hot_cold_basic_blocks for complete details. */
+
+ if (BB_PARTITION (src) != BB_PARTITION (target))
+ return NULL;
+
+ /* We can replace or remove a complex jump only when we have exactly
+ two edges. Also, if we have exactly one outgoing edge, we can
+ redirect that. */
+ if (EDGE_COUNT (src->succs) >= 3
+ /* Verify that all targets will be TARGET. Specifically, the
+ edge that is not E must also go to TARGET. */
+ || (EDGE_COUNT (src->succs) == 2
+ && EDGE_SUCC (src, EDGE_SUCC (src, 0) == e)->dest != target))
+ return NULL;
+
+ if (!onlyjump_p (insn))
+ return NULL;
+ if ((!optimize || reload_completed) && tablejump_p (insn, NULL, NULL))
+ return NULL;
+
+ /* Avoid removing branch with side effects. */
+ set = single_set (insn);
+ if (!set || side_effects_p (set))
+ return NULL;
+
+ /* In case we zap a conditional jump, we'll need to kill
+ the cc0 setter too. */
+ kill_from = insn;
+#ifdef HAVE_cc0
+ if (reg_mentioned_p (cc0_rtx, PATTERN (insn))
+ && only_sets_cc0_p (PREV_INSN (insn)))
+ kill_from = PREV_INSN (insn);
+#endif
+
+ /* See if we can create the fallthru edge. */
+ if (in_cfglayout || can_fallthru (src, target))
+ {
+ if (dump_file)
+ fprintf (dump_file, "Removing jump %i.\n", INSN_UID (insn));
+ fallthru = 1;
+
+ /* Selectively unlink whole insn chain. */
+ if (in_cfglayout)
+ {
+ rtx insn = BB_FOOTER (src);
+
+ delete_insn_chain (kill_from, BB_END (src), false);
+
+ /* Remove barriers but keep jumptables. */
+ while (insn)
+ {
+ if (BARRIER_P (insn))
+ {
+ if (PREV_INSN (insn))
+ NEXT_INSN (PREV_INSN (insn)) = NEXT_INSN (insn);
+ else
+ BB_FOOTER (src) = NEXT_INSN (insn);
+ if (NEXT_INSN (insn))
+ PREV_INSN (NEXT_INSN (insn)) = PREV_INSN (insn);
+ }
+ if (LABEL_P (insn))
+ break;
+ insn = NEXT_INSN (insn);
+ }
+ }
+ else
+ delete_insn_chain (kill_from, PREV_INSN (BB_HEAD (target)),
+ false);
+ }
+
+ /* If this already is simplejump, redirect it. */
+ else if (simplejump_p (insn))
+ {
+ if (e->dest == target)
+ return NULL;
+ if (dump_file)
+ fprintf (dump_file, "Redirecting jump %i from %i to %i.\n",
+ INSN_UID (insn), e->dest->index, target->index);
+ if (!redirect_jump (insn, block_label (target), 0))
+ {
+ gcc_assert (target == EXIT_BLOCK_PTR_FOR_FN (cfun));
+ return NULL;
+ }
+ }
+
+ /* Cannot do anything for target exit block. */
+ else if (target == EXIT_BLOCK_PTR_FOR_FN (cfun))
+ return NULL;
+
+ /* Or replace possibly complicated jump insn by simple jump insn. */
+ else
+ {
+ rtx target_label = block_label (target);
+ rtx barrier, label, table;
+
+ emit_jump_insn_after_noloc (gen_jump (target_label), insn);
+ JUMP_LABEL (BB_END (src)) = target_label;
+ LABEL_NUSES (target_label)++;
+ if (dump_file)
+ fprintf (dump_file, "Replacing insn %i by jump %i\n",
+ INSN_UID (insn), INSN_UID (BB_END (src)));
+
+
+ delete_insn_chain (kill_from, insn, false);
+
+ /* Recognize a tablejump that we are converting to a
+ simple jump and remove its associated CODE_LABEL
+ and ADDR_VEC or ADDR_DIFF_VEC. */
+ if (tablejump_p (insn, &label, &table))
+ delete_insn_chain (label, table, false);
+
+ barrier = next_nonnote_insn (BB_END (src));
+ if (!barrier || !BARRIER_P (barrier))
+ emit_barrier_after (BB_END (src));
+ else
+ {
+ if (barrier != NEXT_INSN (BB_END (src)))
+ {
+ /* Move the jump before barrier so that the notes
+ which originally were or were created before jump table are
+ inside the basic block. */
+ rtx new_insn = BB_END (src);
+
+ update_bb_for_insn_chain (NEXT_INSN (BB_END (src)),
+ PREV_INSN (barrier), src);
+
+ NEXT_INSN (PREV_INSN (new_insn)) = NEXT_INSN (new_insn);
+ PREV_INSN (NEXT_INSN (new_insn)) = PREV_INSN (new_insn);
+
+ NEXT_INSN (new_insn) = barrier;
+ NEXT_INSN (PREV_INSN (barrier)) = new_insn;
+
+ PREV_INSN (new_insn) = PREV_INSN (barrier);
+ PREV_INSN (barrier) = new_insn;
+ }
+ }
+ }
+
+ /* Keep only one edge out and set proper flags. */
+ if (!single_succ_p (src))
+ remove_edge (e);
+ gcc_assert (single_succ_p (src));
+
+ e = single_succ_edge (src);
+ if (fallthru)
+ e->flags = EDGE_FALLTHRU;
+ else
+ e->flags = 0;
+
+ e->probability = REG_BR_PROB_BASE;
+ e->count = src->count;
+
+ if (e->dest != target)
+ redirect_edge_succ (e, target);
+ return e;
+}
+
+/* Subroutine of redirect_branch_edge that tries to patch the jump
+ instruction INSN so that it reaches block NEW. Do this
+ only when it originally reached block OLD. Return true if this
+ worked or the original target wasn't OLD, return false if redirection
+ doesn't work. */
+
+static bool
+patch_jump_insn (rtx insn, rtx old_label, basic_block new_bb)
+{
+ rtx tmp;
+ /* Recognize a tablejump and adjust all matching cases. */
+ if (tablejump_p (insn, NULL, &tmp))
+ {
+ rtvec vec;
+ int j;
+ rtx new_label = block_label (new_bb);
+
+ if (new_bb == EXIT_BLOCK_PTR_FOR_FN (cfun))
+ return false;
+ if (GET_CODE (PATTERN (tmp)) == ADDR_VEC)
+ vec = XVEC (PATTERN (tmp), 0);
+ else
+ vec = XVEC (PATTERN (tmp), 1);
+
+ for (j = GET_NUM_ELEM (vec) - 1; j >= 0; --j)
+ if (XEXP (RTVEC_ELT (vec, j), 0) == old_label)
+ {
+ RTVEC_ELT (vec, j) = gen_rtx_LABEL_REF (Pmode, new_label);
+ --LABEL_NUSES (old_label);
+ ++LABEL_NUSES (new_label);
+ }
+
+ /* Handle casesi dispatch insns. */
+ if ((tmp = single_set (insn)) != NULL
+ && SET_DEST (tmp) == pc_rtx
+ && GET_CODE (SET_SRC (tmp)) == IF_THEN_ELSE
+ && GET_CODE (XEXP (SET_SRC (tmp), 2)) == LABEL_REF
+ && XEXP (XEXP (SET_SRC (tmp), 2), 0) == old_label)
+ {
+ XEXP (SET_SRC (tmp), 2) = gen_rtx_LABEL_REF (Pmode,
+ new_label);
+ --LABEL_NUSES (old_label);
+ ++LABEL_NUSES (new_label);
+ }
+ }
+ else if ((tmp = extract_asm_operands (PATTERN (insn))) != NULL)
+ {
+ int i, n = ASM_OPERANDS_LABEL_LENGTH (tmp);
+ rtx new_label, note;
+
+ if (new_bb == EXIT_BLOCK_PTR_FOR_FN (cfun))
+ return false;
+ new_label = block_label (new_bb);
+
+ for (i = 0; i < n; ++i)
+ {
+ rtx old_ref = ASM_OPERANDS_LABEL (tmp, i);
+ gcc_assert (GET_CODE (old_ref) == LABEL_REF);
+ if (XEXP (old_ref, 0) == old_label)
+ {
+ ASM_OPERANDS_LABEL (tmp, i)
+ = gen_rtx_LABEL_REF (Pmode, new_label);
+ --LABEL_NUSES (old_label);
+ ++LABEL_NUSES (new_label);
+ }
+ }
+
+ if (JUMP_LABEL (insn) == old_label)
+ {
+ JUMP_LABEL (insn) = new_label;
+ note = find_reg_note (insn, REG_LABEL_TARGET, new_label);
+ if (note)
+ remove_note (insn, note);
+ }
+ else
+ {
+ note = find_reg_note (insn, REG_LABEL_TARGET, old_label);
+ if (note)
+ remove_note (insn, note);
+ if (JUMP_LABEL (insn) != new_label
+ && !find_reg_note (insn, REG_LABEL_TARGET, new_label))
+ add_reg_note (insn, REG_LABEL_TARGET, new_label);
+ }
+ while ((note = find_reg_note (insn, REG_LABEL_OPERAND, old_label))
+ != NULL_RTX)
+ XEXP (note, 0) = new_label;
+ }
+ else
+ {
+ /* ?? We may play the games with moving the named labels from
+ one basic block to the other in case only one computed_jump is
+ available. */
+ if (computed_jump_p (insn)
+ /* A return instruction can't be redirected. */
+ || returnjump_p (insn))
+ return false;
+
+ if (!currently_expanding_to_rtl || JUMP_LABEL (insn) == old_label)
+ {
+ /* If the insn doesn't go where we think, we're confused. */
+ gcc_assert (JUMP_LABEL (insn) == old_label);
+
+ /* If the substitution doesn't succeed, die. This can happen
+ if the back end emitted unrecognizable instructions or if
+ target is exit block on some arches. */
+ if (!redirect_jump (insn, block_label (new_bb), 0))
+ {
+ gcc_assert (new_bb == EXIT_BLOCK_PTR_FOR_FN (cfun));
+ return false;
+ }
+ }
+ }
+ return true;
+}
+
+
+/* Redirect edge representing branch of (un)conditional jump or tablejump,
+ NULL on failure */
+static edge
+redirect_branch_edge (edge e, basic_block target)
+{
+ rtx old_label = BB_HEAD (e->dest);
+ basic_block src = e->src;
+ rtx insn = BB_END (src);
+
+ /* We can only redirect non-fallthru edges of jump insn. */
+ if (e->flags & EDGE_FALLTHRU)
+ return NULL;
+ else if (!JUMP_P (insn) && !currently_expanding_to_rtl)
+ return NULL;
+
+ if (!currently_expanding_to_rtl)
+ {
+ if (!patch_jump_insn (insn, old_label, target))
+ return NULL;
+ }
+ else
+ /* When expanding this BB might actually contain multiple
+ jumps (i.e. not yet split by find_many_sub_basic_blocks).
+ Redirect all of those that match our label. */
+ FOR_BB_INSNS (src, insn)
+ if (JUMP_P (insn) && !patch_jump_insn (insn, old_label, target))
+ return NULL;
+
+ if (dump_file)
+ fprintf (dump_file, "Edge %i->%i redirected to %i\n",
+ e->src->index, e->dest->index, target->index);
+
+ if (e->dest != target)
+ e = redirect_edge_succ_nodup (e, target);
+
+ return e;
+}
+
+/* Called when edge E has been redirected to a new destination,
+ in order to update the region crossing flag on the edge and
+ jump. */
+
+static void
+fixup_partition_crossing (edge e)
+{
+ rtx note;
+
+ if (e->src == ENTRY_BLOCK_PTR_FOR_FN (cfun) || e->dest
+ == EXIT_BLOCK_PTR_FOR_FN (cfun))
+ return;
+ /* If we redirected an existing edge, it may already be marked
+ crossing, even though the new src is missing a reg crossing note.
+ But make sure reg crossing note doesn't already exist before
+ inserting. */
+ if (BB_PARTITION (e->src) != BB_PARTITION (e->dest))
+ {
+ e->flags |= EDGE_CROSSING;
+ note = find_reg_note (BB_END (e->src), REG_CROSSING_JUMP, NULL_RTX);
+ if (JUMP_P (BB_END (e->src))
+ && !note)
+ add_reg_note (BB_END (e->src), REG_CROSSING_JUMP, NULL_RTX);
+ }
+ else if (BB_PARTITION (e->src) == BB_PARTITION (e->dest))
+ {
+ e->flags &= ~EDGE_CROSSING;
+ /* Remove the section crossing note from jump at end of
+ src if it exists, and if no other successors are
+ still crossing. */
+ note = find_reg_note (BB_END (e->src), REG_CROSSING_JUMP, NULL_RTX);
+ if (note)
+ {
+ bool has_crossing_succ = false;
+ edge e2;
+ edge_iterator ei;
+ FOR_EACH_EDGE (e2, ei, e->src->succs)
+ {
+ has_crossing_succ |= (e2->flags & EDGE_CROSSING);
+ if (has_crossing_succ)
+ break;
+ }
+ if (!has_crossing_succ)
+ remove_note (BB_END (e->src), note);
+ }
+ }
+}
+
+/* Called when block BB has been reassigned to the cold partition,
+ because it is now dominated by another cold block,
+ to ensure that the region crossing attributes are updated. */
+
+static void
+fixup_new_cold_bb (basic_block bb)
+{
+ edge e;
+ edge_iterator ei;
+
+ /* This is called when a hot bb is found to now be dominated
+ by a cold bb and therefore needs to become cold. Therefore,
+ its preds will no longer be region crossing. Any non-dominating
+ preds that were previously hot would also have become cold
+ in the caller for the same region. Any preds that were previously
+ region-crossing will be adjusted in fixup_partition_crossing. */
+ FOR_EACH_EDGE (e, ei, bb->preds)
+ {
+ fixup_partition_crossing (e);
+ }
+
+ /* Possibly need to make bb's successor edges region crossing,
+ or remove stale region crossing. */
+ FOR_EACH_EDGE (e, ei, bb->succs)
+ {
+ /* We can't have fall-through edges across partition boundaries.
+ Note that force_nonfallthru will do any necessary partition
+ boundary fixup by calling fixup_partition_crossing itself. */
+ if ((e->flags & EDGE_FALLTHRU)
+ && BB_PARTITION (bb) != BB_PARTITION (e->dest)
+ && e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun))
+ force_nonfallthru (e);
+ else
+ fixup_partition_crossing (e);
+ }
+}
+
+/* Attempt to change code to redirect edge E to TARGET. Don't do that on
+ expense of adding new instructions or reordering basic blocks.
+
+ Function can be also called with edge destination equivalent to the TARGET.
+ Then it should try the simplifications and do nothing if none is possible.
+
+ Return edge representing the branch if transformation succeeded. Return NULL
+ on failure.
+ We still return NULL in case E already destinated TARGET and we didn't
+ managed to simplify instruction stream. */
+
+static edge
+rtl_redirect_edge_and_branch (edge e, basic_block target)
+{
+ edge ret;
+ basic_block src = e->src;
+ basic_block dest = e->dest;
+
+ if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH))
+ return NULL;
+
+ if (dest == target)
+ return e;
+
+ if ((ret = try_redirect_by_replacing_jump (e, target, false)) != NULL)
+ {
+ df_set_bb_dirty (src);
+ fixup_partition_crossing (ret);
+ return ret;
+ }
+
+ ret = redirect_branch_edge (e, target);
+ if (!ret)
+ return NULL;
+
+ df_set_bb_dirty (src);
+ fixup_partition_crossing (ret);
+ return ret;
+}
+
+/* Emit a barrier after BB, into the footer if we are in CFGLAYOUT mode. */
+
+void
+emit_barrier_after_bb (basic_block bb)
+{
+ rtx barrier = emit_barrier_after (BB_END (bb));
+ gcc_assert (current_ir_type () == IR_RTL_CFGRTL
+ || current_ir_type () == IR_RTL_CFGLAYOUT);
+ if (current_ir_type () == IR_RTL_CFGLAYOUT)
+ BB_FOOTER (bb) = unlink_insn_chain (barrier, barrier);
+}
+
+/* Like force_nonfallthru below, but additionally performs redirection
+ Used by redirect_edge_and_branch_force. JUMP_LABEL is used only
+ when redirecting to the EXIT_BLOCK, it is either ret_rtx or
+ simple_return_rtx, indicating which kind of returnjump to create.
+ It should be NULL otherwise. */
+
+basic_block
+force_nonfallthru_and_redirect (edge e, basic_block target, rtx jump_label)
+{
+ basic_block jump_block, new_bb = NULL, src = e->src;
+ rtx note;
+ edge new_edge;
+ int abnormal_edge_flags = 0;
+ bool asm_goto_edge = false;
+ int loc;
+
+ /* In the case the last instruction is conditional jump to the next
+ instruction, first redirect the jump itself and then continue
+ by creating a basic block afterwards to redirect fallthru edge. */
+ if (e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun)
+ && e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)
+ && any_condjump_p (BB_END (e->src))
+ && JUMP_LABEL (BB_END (e->src)) == BB_HEAD (e->dest))
+ {
+ rtx note;
+ edge b = unchecked_make_edge (e->src, target, 0);
+ bool redirected;
+
+ redirected = redirect_jump (BB_END (e->src), block_label (target), 0);
+ gcc_assert (redirected);
+
+ note = find_reg_note (BB_END (e->src), REG_BR_PROB, NULL_RTX);
+ if (note)
+ {
+ int prob = XINT (note, 0);
+
+ b->probability = prob;
+ /* Update this to use GCOV_COMPUTE_SCALE. */
+ b->count = e->count * prob / REG_BR_PROB_BASE;
+ e->probability -= e->probability;
+ e->count -= b->count;
+ if (e->probability < 0)
+ e->probability = 0;
+ if (e->count < 0)
+ e->count = 0;
+ }
+ }
+
+ if (e->flags & EDGE_ABNORMAL)
+ {
+ /* Irritating special case - fallthru edge to the same block as abnormal
+ edge.
+ We can't redirect abnormal edge, but we still can split the fallthru
+ one and create separate abnormal edge to original destination.
+ This allows bb-reorder to make such edge non-fallthru. */
+ gcc_assert (e->dest == target);
+ abnormal_edge_flags = e->flags & ~EDGE_FALLTHRU;
+ e->flags &= EDGE_FALLTHRU;
+ }
+ else
+ {
+ gcc_assert (e->flags & EDGE_FALLTHRU);
+ if (e->src == ENTRY_BLOCK_PTR_FOR_FN (cfun))
+ {
+ /* We can't redirect the entry block. Create an empty block
+ at the start of the function which we use to add the new
+ jump. */
+ edge tmp;
+ edge_iterator ei;
+ bool found = false;
+
+ basic_block bb = create_basic_block (BB_HEAD (e->dest), NULL,
+ ENTRY_BLOCK_PTR_FOR_FN (cfun));
+
+ /* Change the existing edge's source to be the new block, and add
+ a new edge from the entry block to the new block. */
+ e->src = bb;
+ for (ei = ei_start (ENTRY_BLOCK_PTR_FOR_FN (cfun)->succs);
+ (tmp = ei_safe_edge (ei)); )
+ {
+ if (tmp == e)
+ {
+ ENTRY_BLOCK_PTR_FOR_FN (cfun)->succs->unordered_remove (ei.index);
+ found = true;
+ break;
+ }
+ else
+ ei_next (&ei);
+ }
+
+ gcc_assert (found);
+
+ vec_safe_push (bb->succs, e);
+ make_single_succ_edge (ENTRY_BLOCK_PTR_FOR_FN (cfun), bb,
+ EDGE_FALLTHRU);
+ }
+ }
+
+ /* If e->src ends with asm goto, see if any of the ASM_OPERANDS_LABELs
+ don't point to the target or fallthru label. */
+ if (JUMP_P (BB_END (e->src))
+ && target != EXIT_BLOCK_PTR_FOR_FN (cfun)
+ && (e->flags & EDGE_FALLTHRU)
+ && (note = extract_asm_operands (PATTERN (BB_END (e->src)))))
+ {
+ int i, n = ASM_OPERANDS_LABEL_LENGTH (note);
+ bool adjust_jump_target = false;
+
+ for (i = 0; i < n; ++i)
+ {
+ if (XEXP (ASM_OPERANDS_LABEL (note, i), 0) == BB_HEAD (e->dest))
+ {
+ LABEL_NUSES (XEXP (ASM_OPERANDS_LABEL (note, i), 0))--;
+ XEXP (ASM_OPERANDS_LABEL (note, i), 0) = block_label (target);
+ LABEL_NUSES (XEXP (ASM_OPERANDS_LABEL (note, i), 0))++;
+ adjust_jump_target = true;
+ }
+ if (XEXP (ASM_OPERANDS_LABEL (note, i), 0) == BB_HEAD (target))
+ asm_goto_edge = true;
+ }
+ if (adjust_jump_target)
+ {
+ rtx insn = BB_END (e->src), note;
+ rtx old_label = BB_HEAD (e->dest);
+ rtx new_label = BB_HEAD (target);
+
+ if (JUMP_LABEL (insn) == old_label)
+ {
+ JUMP_LABEL (insn) = new_label;
+ note = find_reg_note (insn, REG_LABEL_TARGET, new_label);
+ if (note)
+ remove_note (insn, note);
+ }
+ else
+ {
+ note = find_reg_note (insn, REG_LABEL_TARGET, old_label);
+ if (note)
+ remove_note (insn, note);
+ if (JUMP_LABEL (insn) != new_label
+ && !find_reg_note (insn, REG_LABEL_TARGET, new_label))
+ add_reg_note (insn, REG_LABEL_TARGET, new_label);
+ }
+ while ((note = find_reg_note (insn, REG_LABEL_OPERAND, old_label))
+ != NULL_RTX)
+ XEXP (note, 0) = new_label;
+ }
+ }
+
+ if (EDGE_COUNT (e->src->succs) >= 2 || abnormal_edge_flags || asm_goto_edge)
+ {
+ gcov_type count = e->count;
+ int probability = e->probability;
+ /* Create the new structures. */
+
+ /* If the old block ended with a tablejump, skip its table
+ by searching forward from there. Otherwise start searching
+ forward from the last instruction of the old block. */
+ if (!tablejump_p (BB_END (e->src), NULL, &note))
+ note = BB_END (e->src);
+ note = NEXT_INSN (note);
+
+ jump_block = create_basic_block (note, NULL, e->src);
+ jump_block->count = count;
+ jump_block->frequency = EDGE_FREQUENCY (e);
+
+ /* Make sure new block ends up in correct hot/cold section. */
+
+ BB_COPY_PARTITION (jump_block, e->src);
+
+ /* Wire edge in. */
+ new_edge = make_edge (e->src, jump_block, EDGE_FALLTHRU);
+ new_edge->probability = probability;
+ new_edge->count = count;
+
+ /* Redirect old edge. */
+ redirect_edge_pred (e, jump_block);
+ e->probability = REG_BR_PROB_BASE;
+
+ /* If e->src was previously region crossing, it no longer is
+ and the reg crossing note should be removed. */
+ fixup_partition_crossing (new_edge);
+
+ /* If asm goto has any label refs to target's label,
+ add also edge from asm goto bb to target. */
+ if (asm_goto_edge)
+ {
+ new_edge->probability /= 2;
+ new_edge->count /= 2;
+ jump_block->count /= 2;
+ jump_block->frequency /= 2;
+ new_edge = make_edge (new_edge->src, target,
+ e->flags & ~EDGE_FALLTHRU);
+ new_edge->probability = probability - probability / 2;
+ new_edge->count = count - count / 2;
+ }
+
+ new_bb = jump_block;
+ }
+ else
+ jump_block = e->src;
+
+ loc = e->goto_locus;
+ e->flags &= ~EDGE_FALLTHRU;
+ if (target == EXIT_BLOCK_PTR_FOR_FN (cfun))
+ {
+ if (jump_label == ret_rtx)
+ {
+#ifdef HAVE_return
+ emit_jump_insn_after_setloc (gen_return (), BB_END (jump_block), loc);
+#else
+ gcc_unreachable ();
+#endif
+ }
+ else
+ {
+ gcc_assert (jump_label == simple_return_rtx);
+#ifdef HAVE_simple_return
+ emit_jump_insn_after_setloc (gen_simple_return (),
+ BB_END (jump_block), loc);
+#else
+ gcc_unreachable ();
+#endif
+ }
+ set_return_jump_label (BB_END (jump_block));
+ }
+ else
+ {
+ rtx label = block_label (target);
+ emit_jump_insn_after_setloc (gen_jump (label), BB_END (jump_block), loc);
+ JUMP_LABEL (BB_END (jump_block)) = label;
+ LABEL_NUSES (label)++;
+ }
+
+ /* We might be in cfg layout mode, and if so, the following routine will
+ insert the barrier correctly. */
+ emit_barrier_after_bb (jump_block);
+ redirect_edge_succ_nodup (e, target);
+
+ if (abnormal_edge_flags)
+ make_edge (src, target, abnormal_edge_flags);
+
+ df_mark_solutions_dirty ();
+ fixup_partition_crossing (e);
+ return new_bb;
+}
+
+/* Edge E is assumed to be fallthru edge. Emit needed jump instruction
+ (and possibly create new basic block) to make edge non-fallthru.
+ Return newly created BB or NULL if none. */
+
+static basic_block
+rtl_force_nonfallthru (edge e)
+{
+ return force_nonfallthru_and_redirect (e, e->dest, NULL_RTX);
+}
+
+/* Redirect edge even at the expense of creating new jump insn or
+ basic block. Return new basic block if created, NULL otherwise.
+ Conversion must be possible. */
+
+static basic_block
+rtl_redirect_edge_and_branch_force (edge e, basic_block target)
+{
+ if (redirect_edge_and_branch (e, target)
+ || e->dest == target)
+ return NULL;
+
+ /* In case the edge redirection failed, try to force it to be non-fallthru
+ and redirect newly created simplejump. */
+ df_set_bb_dirty (e->src);
+ return force_nonfallthru_and_redirect (e, target, NULL_RTX);
+}
+
+/* The given edge should potentially be a fallthru edge. If that is in
+ fact true, delete the jump and barriers that are in the way. */
+
+static void
+rtl_tidy_fallthru_edge (edge e)
+{
+ rtx q;
+ basic_block b = e->src, c = b->next_bb;
+
+ /* ??? In a late-running flow pass, other folks may have deleted basic
+ blocks by nopping out blocks, leaving multiple BARRIERs between here
+ and the target label. They ought to be chastised and fixed.
+
+ We can also wind up with a sequence of undeletable labels between
+ one block and the next.
+
+ So search through a sequence of barriers, labels, and notes for
+ the head of block C and assert that we really do fall through. */
+
+ for (q = NEXT_INSN (BB_END (b)); q != BB_HEAD (c); q = NEXT_INSN (q))
+ if (INSN_P (q))
+ return;
+
+ /* Remove what will soon cease being the jump insn from the source block.
+ If block B consisted only of this single jump, turn it into a deleted
+ note. */
+ q = BB_END (b);
+ if (JUMP_P (q)
+ && onlyjump_p (q)
+ && (any_uncondjump_p (q)
+ || single_succ_p (b)))
+ {
+#ifdef HAVE_cc0
+ /* If this was a conditional jump, we need to also delete
+ the insn that set cc0. */
+ if (any_condjump_p (q) && only_sets_cc0_p (PREV_INSN (q)))
+ q = PREV_INSN (q);
+#endif
+
+ q = PREV_INSN (q);
+ }
+
+ /* Selectively unlink the sequence. */
+ if (q != PREV_INSN (BB_HEAD (c)))
+ delete_insn_chain (NEXT_INSN (q), PREV_INSN (BB_HEAD (c)), false);
+
+ e->flags |= EDGE_FALLTHRU;
+}
+
+/* Should move basic block BB after basic block AFTER. NIY. */
+
+static bool
+rtl_move_block_after (basic_block bb ATTRIBUTE_UNUSED,
+ basic_block after ATTRIBUTE_UNUSED)
+{
+ return false;
+}
+
+/* Locate the last bb in the same partition as START_BB. */
+
+static basic_block
+last_bb_in_partition (basic_block start_bb)
+{
+ basic_block bb;
+ FOR_BB_BETWEEN (bb, start_bb, EXIT_BLOCK_PTR_FOR_FN (cfun), next_bb)
+ {
+ if (BB_PARTITION (start_bb) != BB_PARTITION (bb->next_bb))
+ return bb;
+ }
+ /* Return bb before the exit block. */
+ return bb->prev_bb;
+}
+
+/* Split a (typically critical) edge. Return the new block.
+ The edge must not be abnormal.
+
+ ??? The code generally expects to be called on critical edges.
+ The case of a block ending in an unconditional jump to a
+ block with multiple predecessors is not handled optimally. */
+
+static basic_block
+rtl_split_edge (edge edge_in)
+{
+ basic_block bb, new_bb;
+ rtx before;
+
+ /* Abnormal edges cannot be split. */
+ gcc_assert (!(edge_in->flags & EDGE_ABNORMAL));
+
+ /* We are going to place the new block in front of edge destination.
+ Avoid existence of fallthru predecessors. */
+ if ((edge_in->flags & EDGE_FALLTHRU) == 0)
+ {
+ edge e = find_fallthru_edge (edge_in->dest->preds);
+
+ if (e)
+ force_nonfallthru (e);
+ }
+
+ /* Create the basic block note. */
+ if (edge_in->dest != EXIT_BLOCK_PTR_FOR_FN (cfun))
+ before = BB_HEAD (edge_in->dest);
+ else
+ before = NULL_RTX;
+
+ /* If this is a fall through edge to the exit block, the blocks might be
+ not adjacent, and the right place is after the source. */
+ if ((edge_in->flags & EDGE_FALLTHRU)
+ && edge_in->dest == EXIT_BLOCK_PTR_FOR_FN (cfun))
+ {
+ before = NEXT_INSN (BB_END (edge_in->src));
+ bb = create_basic_block (before, NULL, edge_in->src);
+ BB_COPY_PARTITION (bb, edge_in->src);
+ }
+ else
+ {
+ if (edge_in->src == ENTRY_BLOCK_PTR_FOR_FN (cfun))
+ {
+ bb = create_basic_block (before, NULL, edge_in->dest->prev_bb);
+ BB_COPY_PARTITION (bb, edge_in->dest);
+ }
+ else
+ {
+ basic_block after = edge_in->dest->prev_bb;
+ /* If this is post-bb reordering, and the edge crosses a partition
+ boundary, the new block needs to be inserted in the bb chain
+ at the end of the src partition (since we put the new bb into
+ that partition, see below). Otherwise we may end up creating
+ an extra partition crossing in the chain, which is illegal.
+ It can't go after the src, because src may have a fall-through
+ to a different block. */
+ if (crtl->bb_reorder_complete
+ && (edge_in->flags & EDGE_CROSSING))
+ {
+ after = last_bb_in_partition (edge_in->src);
+ before = NEXT_INSN (BB_END (after));
+ /* The instruction following the last bb in partition should
+ be a barrier, since it cannot end in a fall-through. */
+ gcc_checking_assert (BARRIER_P (before));
+ before = NEXT_INSN (before);
+ }
+ bb = create_basic_block (before, NULL, after);
+ /* Put the split bb into the src partition, to avoid creating
+ a situation where a cold bb dominates a hot bb, in the case
+ where src is cold and dest is hot. The src will dominate
+ the new bb (whereas it might not have dominated dest). */
+ BB_COPY_PARTITION (bb, edge_in->src);
+ }
+ }
+
+ make_single_succ_edge (bb, edge_in->dest, EDGE_FALLTHRU);
+
+ /* Can't allow a region crossing edge to be fallthrough. */
+ if (BB_PARTITION (bb) != BB_PARTITION (edge_in->dest)
+ && edge_in->dest != EXIT_BLOCK_PTR_FOR_FN (cfun))
+ {
+ new_bb = force_nonfallthru (single_succ_edge (bb));
+ gcc_assert (!new_bb);
+ }
+
+ /* For non-fallthru edges, we must adjust the predecessor's
+ jump instruction to target our new block. */
+ if ((edge_in->flags & EDGE_FALLTHRU) == 0)
+ {
+ edge redirected = redirect_edge_and_branch (edge_in, bb);
+ gcc_assert (redirected);
+ }
+ else
+ {
+ if (edge_in->src != ENTRY_BLOCK_PTR_FOR_FN (cfun))
+ {
+ /* For asm goto even splitting of fallthru edge might
+ need insn patching, as other labels might point to the
+ old label. */
+ rtx last = BB_END (edge_in->src);
+ if (last
+ && JUMP_P (last)
+ && edge_in->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)
+ && extract_asm_operands (PATTERN (last)) != NULL_RTX
+ && patch_jump_insn (last, before, bb))
+ df_set_bb_dirty (edge_in->src);
+ }
+ redirect_edge_succ (edge_in, bb);
+ }
+
+ return bb;
+}
+
+/* Queue instructions for insertion on an edge between two basic blocks.
+ The new instructions and basic blocks (if any) will not appear in the
+ CFG until commit_edge_insertions is called. */
+
+void
+insert_insn_on_edge (rtx pattern, edge e)
+{
+ /* We cannot insert instructions on an abnormal critical edge.
+ It will be easier to find the culprit if we die now. */
+ gcc_assert (!((e->flags & EDGE_ABNORMAL) && EDGE_CRITICAL_P (e)));
+
+ if (e->insns.r == NULL_RTX)
+ start_sequence ();
+ else
+ push_to_sequence (e->insns.r);
+
+ emit_insn (pattern);
+
+ e->insns.r = get_insns ();
+ end_sequence ();
+}
+
+/* Update the CFG for the instructions queued on edge E. */
+
+void
+commit_one_edge_insertion (edge e)
+{
+ rtx before = NULL_RTX, after = NULL_RTX, insns, tmp, last;
+ basic_block bb;
+
+ /* Pull the insns off the edge now since the edge might go away. */
+ insns = e->insns.r;
+ e->insns.r = NULL_RTX;
+
+ /* Figure out where to put these insns. If the destination has
+ one predecessor, insert there. Except for the exit block. */
+ if (single_pred_p (e->dest) && e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun))
+ {
+ bb = e->dest;
+
+ /* Get the location correct wrt a code label, and "nice" wrt
+ a basic block note, and before everything else. */
+ tmp = BB_HEAD (bb);
+ if (LABEL_P (tmp))
+ tmp = NEXT_INSN (tmp);
+ if (NOTE_INSN_BASIC_BLOCK_P (tmp))
+ tmp = NEXT_INSN (tmp);
+ if (tmp == BB_HEAD (bb))
+ before = tmp;
+ else if (tmp)
+ after = PREV_INSN (tmp);
+ else
+ after = get_last_insn ();
+ }
+
+ /* If the source has one successor and the edge is not abnormal,
+ insert there. Except for the entry block.
+ Don't do this if the predecessor ends in a jump other than
+ unconditional simple jump. E.g. for asm goto that points all
+ its labels at the fallthru basic block, we can't insert instructions
+ before the asm goto, as the asm goto can have various of side effects,
+ and can't emit instructions after the asm goto, as it must end
+ the basic block. */
+ else if ((e->flags & EDGE_ABNORMAL) == 0
+ && single_succ_p (e->src)
+ && e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun)
+ && (!JUMP_P (BB_END (e->src))
+ || simplejump_p (BB_END (e->src))))
+ {
+ bb = e->src;
+
+ /* It is possible to have a non-simple jump here. Consider a target
+ where some forms of unconditional jumps clobber a register. This
+ happens on the fr30 for example.
+
+ We know this block has a single successor, so we can just emit
+ the queued insns before the jump. */
+ if (JUMP_P (BB_END (bb)))
+ before = BB_END (bb);
+ else
+ {
+ /* We'd better be fallthru, or we've lost track of what's what. */
+ gcc_assert (e->flags & EDGE_FALLTHRU);
+
+ after = BB_END (bb);
+ }
+ }
+
+ /* Otherwise we must split the edge. */
+ else
+ {
+ bb = split_edge (e);
+
+ /* If E crossed a partition boundary, we needed to make bb end in
+ a region-crossing jump, even though it was originally fallthru. */
+ if (JUMP_P (BB_END (bb)))
+ before = BB_END (bb);
+ else
+ after = BB_END (bb);
+ }
+
+ /* Now that we've found the spot, do the insertion. */
+ if (before)
+ {
+ emit_insn_before_noloc (insns, before, bb);
+ last = prev_nonnote_insn (before);
+ }
+ else
+ last = emit_insn_after_noloc (insns, after, bb);
+
+ if (returnjump_p (last))
+ {
+ /* ??? Remove all outgoing edges from BB and add one for EXIT.
+ This is not currently a problem because this only happens
+ for the (single) epilogue, which already has a fallthru edge
+ to EXIT. */
+
+ e = single_succ_edge (bb);
+ gcc_assert (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun)
+ && single_succ_p (bb) && (e->flags & EDGE_FALLTHRU));
+
+ e->flags &= ~EDGE_FALLTHRU;
+ emit_barrier_after (last);
+
+ if (before)
+ delete_insn (before);
+ }
+ else
+ gcc_assert (!JUMP_P (last));
+}
+
+/* Update the CFG for all queued instructions. */
+
+void
+commit_edge_insertions (void)
+{
+ basic_block bb;
+
+ /* Optimization passes that invoke this routine can cause hot blocks
+ previously reached by both hot and cold blocks to become dominated only
+ by cold blocks. This will cause the verification below to fail,
+ and lead to now cold code in the hot section. In some cases this
+ may only be visible after newly unreachable blocks are deleted,
+ which will be done by fixup_partitions. */
+ fixup_partitions ();
+
+#ifdef ENABLE_CHECKING
+ verify_flow_info ();
+#endif
+
+ FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR_FOR_FN (cfun),
+ EXIT_BLOCK_PTR_FOR_FN (cfun), next_bb)
+ {
+ edge e;
+ edge_iterator ei;
+
+ FOR_EACH_EDGE (e, ei, bb->succs)
+ if (e->insns.r)
+ commit_one_edge_insertion (e);
+ }
+}
+
+
+/* Print out RTL-specific basic block information (live information
+ at start and end with TDF_DETAILS). FLAGS are the TDF_* masks
+ documented in dumpfile.h. */
+
+static void
+rtl_dump_bb (FILE *outf, basic_block bb, int indent, int flags)
+{
+ rtx insn;
+ rtx last;
+ char *s_indent;
+
+ s_indent = (char *) alloca ((size_t) indent + 1);
+ memset (s_indent, ' ', (size_t) indent);
+ s_indent[indent] = '\0';
+
+ if (df && (flags & TDF_DETAILS))
+ {
+ df_dump_top (bb, outf);
+ putc ('\n', outf);
+ }
+
+ if (bb->index != ENTRY_BLOCK && bb->index != EXIT_BLOCK)
+ for (insn = BB_HEAD (bb), last = NEXT_INSN (BB_END (bb)); insn != last;
+ insn = NEXT_INSN (insn))
+ {
+ if (flags & TDF_DETAILS)
+ df_dump_insn_top (insn, outf);
+ if (! (flags & TDF_SLIM))
+ print_rtl_single (outf, insn);
+ else
+ dump_insn_slim (outf, insn);
+ if (flags & TDF_DETAILS)
+ df_dump_insn_bottom (insn, outf);
+ }
+
+ if (df && (flags & TDF_DETAILS))
+ {
+ df_dump_bottom (bb, outf);
+ putc ('\n', outf);
+ }
+
+}
+
+/* Like dump_function_to_file, but for RTL. Print out dataflow information
+ for the start of each basic block. FLAGS are the TDF_* masks documented
+ in dumpfile.h. */
+
+void
+print_rtl_with_bb (FILE *outf, const_rtx rtx_first, int flags)
+{
+ const_rtx tmp_rtx;
+ if (rtx_first == 0)
+ fprintf (outf, "(nil)\n");
+ else
+ {
+ enum bb_state { NOT_IN_BB, IN_ONE_BB, IN_MULTIPLE_BB };
+ int max_uid = get_max_uid ();
+ basic_block *start = XCNEWVEC (basic_block, max_uid);
+ basic_block *end = XCNEWVEC (basic_block, max_uid);
+ enum bb_state *in_bb_p = XCNEWVEC (enum bb_state, max_uid);
+ basic_block bb;
+
+ /* After freeing the CFG, we still have BLOCK_FOR_INSN set on most
+ insns, but the CFG is not maintained so the basic block info
+ is not reliable. Therefore it's omitted from the dumps. */
+ if (! (cfun->curr_properties & PROP_cfg))
+ flags &= ~TDF_BLOCKS;
+
+ if (df)
+ df_dump_start (outf);
+
+ if (flags & TDF_BLOCKS)
+ {
+ FOR_EACH_BB_REVERSE_FN (bb, cfun)
+ {
+ rtx x;
+
+ start[INSN_UID (BB_HEAD (bb))] = bb;
+ end[INSN_UID (BB_END (bb))] = bb;
+ for (x = BB_HEAD (bb); x != NULL_RTX; x = NEXT_INSN (x))
+ {
+ enum bb_state state = IN_MULTIPLE_BB;
+
+ if (in_bb_p[INSN_UID (x)] == NOT_IN_BB)
+ state = IN_ONE_BB;
+ in_bb_p[INSN_UID (x)] = state;
+
+ if (x == BB_END (bb))
+ break;
+ }
+ }
+ }
+
+ for (tmp_rtx = rtx_first; NULL != tmp_rtx; tmp_rtx = NEXT_INSN (tmp_rtx))
+ {
+ if (flags & TDF_BLOCKS)
+ {
+ bb = start[INSN_UID (tmp_rtx)];
+ if (bb != NULL)
+ {
+ dump_bb_info (outf, bb, 0, dump_flags | TDF_COMMENT, true, false);
+ if (df && (flags & TDF_DETAILS))
+ df_dump_top (bb, outf);
+ }
+
+ if (in_bb_p[INSN_UID (tmp_rtx)] == NOT_IN_BB
+ && !NOTE_P (tmp_rtx)
+ && !BARRIER_P (tmp_rtx))
+ fprintf (outf, ";; Insn is not within a basic block\n");
+ else if (in_bb_p[INSN_UID (tmp_rtx)] == IN_MULTIPLE_BB)
+ fprintf (outf, ";; Insn is in multiple basic blocks\n");
+ }
+
+ if (flags & TDF_DETAILS)
+ df_dump_insn_top (tmp_rtx, outf);
+ if (! (flags & TDF_SLIM))
+ print_rtl_single (outf, tmp_rtx);
+ else
+ dump_insn_slim (outf, tmp_rtx);
+ if (flags & TDF_DETAILS)
+ df_dump_insn_bottom (tmp_rtx, outf);
+
+ if (flags & TDF_BLOCKS)
+ {
+ bb = end[INSN_UID (tmp_rtx)];
+ if (bb != NULL)
+ {
+ dump_bb_info (outf, bb, 0, dump_flags | TDF_COMMENT, false, true);
+ if (df && (flags & TDF_DETAILS))
+ df_dump_bottom (bb, outf);
+ putc ('\n', outf);
+ }
+ }
+ }
+
+ free (start);
+ free (end);
+ free (in_bb_p);
+ }
+}
+
+/* Update the branch probability of BB if a REG_BR_PROB is present. */
+
+void
+update_br_prob_note (basic_block bb)
+{
+ rtx note;
+ if (!JUMP_P (BB_END (bb)))
+ return;
+ note = find_reg_note (BB_END (bb), REG_BR_PROB, NULL_RTX);
+ if (!note || XINT (note, 0) == BRANCH_EDGE (bb)->probability)
+ return;
+ XINT (note, 0) = BRANCH_EDGE (bb)->probability;
+}
+
+/* Get the last insn associated with block BB (that includes barriers and
+ tablejumps after BB). */
+rtx
+get_last_bb_insn (basic_block bb)
+{
+ rtx tmp;
+ rtx end = BB_END (bb);
+
+ /* Include any jump table following the basic block. */
+ if (tablejump_p (end, NULL, &tmp))
+ end = tmp;
+
+ /* Include any barriers that may follow the basic block. */
+ tmp = next_nonnote_insn_bb (end);
+ while (tmp && BARRIER_P (tmp))
+ {
+ end = tmp;
+ tmp = next_nonnote_insn_bb (end);
+ }
+
+ return end;
+}
+
+/* Sanity check partition hotness to ensure that basic blocks in
+   the cold partition don't dominate basic blocks in the hot partition.
+ If FLAG_ONLY is true, report violations as errors. Otherwise
+ re-mark the dominated blocks as cold, since this is run after
+ cfg optimizations that may make hot blocks previously reached
+ by both hot and cold blocks now only reachable along cold paths. */
+
+static vec<basic_block>
+find_partition_fixes (bool flag_only)
+{
+ basic_block bb;
+ vec<basic_block> bbs_in_cold_partition = vNULL;
+ vec<basic_block> bbs_to_fix = vNULL;
+
+ /* Callers check this. */
+ gcc_checking_assert (crtl->has_bb_partition);
+
+ FOR_EACH_BB_FN (bb, cfun)
+ if ((BB_PARTITION (bb) == BB_COLD_PARTITION))
+ bbs_in_cold_partition.safe_push (bb);
+
+ if (bbs_in_cold_partition.is_empty ())
+ return vNULL;
+
+ bool dom_calculated_here = !dom_info_available_p (CDI_DOMINATORS);
+
+ if (dom_calculated_here)
+ calculate_dominance_info (CDI_DOMINATORS);
+
+ while (! bbs_in_cold_partition.is_empty ())
+ {
+ bb = bbs_in_cold_partition.pop ();
+ /* Any blocks dominated by a block in the cold section
+ must also be cold. */
+ basic_block son;
+ for (son = first_dom_son (CDI_DOMINATORS, bb);
+ son;
+ son = next_dom_son (CDI_DOMINATORS, son))
+ {
+ /* If son is not yet cold, then mark it cold here and
+ enqueue it for further processing. */
+ if ((BB_PARTITION (son) != BB_COLD_PARTITION))
+ {
+ if (flag_only)
+ error ("non-cold basic block %d dominated "
+ "by a block in the cold partition (%d)", son->index, bb->index);
+ else
+ BB_SET_PARTITION (son, BB_COLD_PARTITION);
+ bbs_to_fix.safe_push (son);
+ bbs_in_cold_partition.safe_push (son);
+ }
+ }
+ }
+
+ if (dom_calculated_here)
+ free_dominance_info (CDI_DOMINATORS);
+
+ return bbs_to_fix;
+}
+
+/* Perform cleanup on the hot/cold bb partitioning after optimization
+ passes that modify the cfg. */
+
+void
+fixup_partitions (void)
+{
+ basic_block bb;
+
+ if (!crtl->has_bb_partition)
+ return;
+
+ /* Delete any blocks that became unreachable and weren't
+ already cleaned up, for example during edge forwarding
+ and convert_jumps_to_returns. This will expose more
+ opportunities for fixing the partition boundaries here.
+ Also, the calculation of the dominance graph during verification
+ will assert if there are unreachable nodes. */
+ delete_unreachable_blocks ();
+
+ /* If there are partitions, do a sanity check on them: A basic block in
+   a cold partition cannot dominate a basic block in a hot partition.
+ Fixup any that now violate this requirement, as a result of edge
+ forwarding and unreachable block deletion.  */
+ vec<basic_block> bbs_to_fix = find_partition_fixes (false);
+
+ /* Do the partition fixup after all necessary blocks have been converted to
+ cold, so that we only update the region crossings the minimum number of
+ places, which can require forcing edges to be non fallthru. */
+ while (! bbs_to_fix.is_empty ())
+ {
+ bb = bbs_to_fix.pop ();
+ fixup_new_cold_bb (bb);
+ }
+}
+
+/* Verify, in the basic block chain, that there is at most one switch
+ between hot/cold partitions. This condition will not be true until
+ after reorder_basic_blocks is called. */
+
+static int
+verify_hot_cold_block_grouping (void)
+{
+ basic_block bb;
+ int err = 0;
+ bool switched_sections = false;
+ int current_partition = BB_UNPARTITIONED;
+
+ /* Even after bb reordering is complete, we go into cfglayout mode
+ again (in compgoto). Ensure we don't call this before going back
+ into linearized RTL when any layout fixes would have been committed. */
+ if (!crtl->bb_reorder_complete
+ || current_ir_type () != IR_RTL_CFGRTL)
+ return err;
+
+ FOR_EACH_BB_FN (bb, cfun)
+ {
+ if (current_partition != BB_UNPARTITIONED
+ && BB_PARTITION (bb) != current_partition)
+ {
+ if (switched_sections)
+ {
+ error ("multiple hot/cold transitions found (bb %i)",
+ bb->index);
+ err = 1;
+ }
+ else
+ switched_sections = true;
+
+ if (!crtl->has_bb_partition)
+ error ("partition found but function partition flag not set");
+ }
+ current_partition = BB_PARTITION (bb);
+ }
+
+ return err;
+}
+
+
+/* Perform several checks on the edges out of each block, such as
+ the consistency of the branch probabilities, the correctness
+ of hot/cold partition crossing edges, and the number of expected
+ successor edges. Also verify that the dominance relationship
+ between hot/cold blocks is sane. */
+
+static int
+rtl_verify_edges (void)
+{
+ int err = 0;
+ basic_block bb;
+
+ FOR_EACH_BB_REVERSE_FN (bb, cfun)
+ {
+ int n_fallthru = 0, n_branch = 0, n_abnormal_call = 0, n_sibcall = 0;
+ int n_eh = 0, n_abnormal = 0;
+ edge e, fallthru = NULL;
+ edge_iterator ei;
+ rtx note;
+ bool has_crossing_edge = false;
+
+ if (JUMP_P (BB_END (bb))
+ && (note = find_reg_note (BB_END (bb), REG_BR_PROB, NULL_RTX))
+ && EDGE_COUNT (bb->succs) >= 2
+ && any_condjump_p (BB_END (bb)))
+ {
+ if (XINT (note, 0) != BRANCH_EDGE (bb)->probability
+ && profile_status_for_fn (cfun) != PROFILE_ABSENT)
+ {
+ error ("verify_flow_info: REG_BR_PROB does not match cfg %i %i",
+ XINT (note, 0), BRANCH_EDGE (bb)->probability);
+ err = 1;
+ }
+ }
+
+ FOR_EACH_EDGE (e, ei, bb->succs)
+ {
+ bool is_crossing;
+
+ if (e->flags & EDGE_FALLTHRU)
+ n_fallthru++, fallthru = e;
+
+ is_crossing = (BB_PARTITION (e->src) != BB_PARTITION (e->dest)
+ && e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun)
+ && e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun));
+ has_crossing_edge |= is_crossing;
+ if (e->flags & EDGE_CROSSING)
+ {
+ if (!is_crossing)
+ {
+ error ("EDGE_CROSSING incorrectly set across same section");
+ err = 1;
+ }
+ if (e->flags & EDGE_FALLTHRU)
+ {
+ error ("fallthru edge crosses section boundary in bb %i",
+ e->src->index);
+ err = 1;
+ }
+ if (e->flags & EDGE_EH)
+ {
+ error ("EH edge crosses section boundary in bb %i",
+ e->src->index);
+ err = 1;
+ }
+ if (JUMP_P (BB_END (bb))
+ && !find_reg_note (BB_END (bb), REG_CROSSING_JUMP, NULL_RTX))
+ {
+ error ("No region crossing jump at section boundary in bb %i",
+ bb->index);
+ err = 1;
+ }
+ }
+ else if (is_crossing)
+ {
+ error ("EDGE_CROSSING missing across section boundary");
+ err = 1;
+ }
+
+ if ((e->flags & ~(EDGE_DFS_BACK
+ | EDGE_CAN_FALLTHRU
+ | EDGE_IRREDUCIBLE_LOOP
+ | EDGE_LOOP_EXIT
+ | EDGE_CROSSING
+ | EDGE_PRESERVE)) == 0)
+ n_branch++;
+
+ if (e->flags & EDGE_ABNORMAL_CALL)
+ n_abnormal_call++;
+
+ if (e->flags & EDGE_SIBCALL)
+ n_sibcall++;
+
+ if (e->flags & EDGE_EH)
+ n_eh++;
+
+ if (e->flags & EDGE_ABNORMAL)
+ n_abnormal++;
+ }
+
+ if (!has_crossing_edge
+ && find_reg_note (BB_END (bb), REG_CROSSING_JUMP, NULL_RTX))
+ {
+ print_rtl_with_bb (stderr, get_insns (), TDF_RTL | TDF_BLOCKS | TDF_DETAILS);
+ error ("Region crossing jump across same section in bb %i",
+ bb->index);
+ err = 1;
+ }
+
+ if (n_eh && !find_reg_note (BB_END (bb), REG_EH_REGION, NULL_RTX))
+ {
+ error ("missing REG_EH_REGION note at the end of bb %i", bb->index);
+ err = 1;
+ }
+ if (n_eh > 1)
+ {
+ error ("too many exception handling edges in bb %i", bb->index);
+ err = 1;
+ }
+ if (n_branch
+ && (!JUMP_P (BB_END (bb))
+ || (n_branch > 1 && (any_uncondjump_p (BB_END (bb))
+ || any_condjump_p (BB_END (bb))))))
+ {
+ error ("too many outgoing branch edges from bb %i", bb->index);
+ err = 1;
+ }
+ if (n_fallthru && any_uncondjump_p (BB_END (bb)))
+ {
+ error ("fallthru edge after unconditional jump in bb %i", bb->index);
+ err = 1;
+ }
+ if (n_branch != 1 && any_uncondjump_p (BB_END (bb)))
+ {
+ error ("wrong number of branch edges after unconditional jump"
+ " in bb %i", bb->index);
+ err = 1;
+ }
+ if (n_branch != 1 && any_condjump_p (BB_END (bb))
+ && JUMP_LABEL (BB_END (bb)) != BB_HEAD (fallthru->dest))
+ {
+ error ("wrong amount of branch edges after conditional jump"
+ " in bb %i", bb->index);
+ err = 1;
+ }
+ if (n_abnormal_call && !CALL_P (BB_END (bb)))
+ {
+ error ("abnormal call edges for non-call insn in bb %i", bb->index);
+ err = 1;
+ }
+ if (n_sibcall && !CALL_P (BB_END (bb)))
+ {
+ error ("sibcall edges for non-call insn in bb %i", bb->index);
+ err = 1;
+ }
+ if (n_abnormal > n_eh
+ && !(CALL_P (BB_END (bb))
+ && n_abnormal == n_abnormal_call + n_sibcall)
+ && (!JUMP_P (BB_END (bb))
+ || any_condjump_p (BB_END (bb))
+ || any_uncondjump_p (BB_END (bb))))
+ {
+ error ("abnormal edges for no purpose in bb %i", bb->index);
+ err = 1;
+ }
+ }
+
+ /* If there are partitions, do a sanity check on them: A basic block in
+   a cold partition cannot dominate a basic block in a hot partition.  */
+ if (crtl->has_bb_partition && !err)
+ {
+ vec<basic_block> bbs_to_fix = find_partition_fixes (true);
+ err = !bbs_to_fix.is_empty ();
+ }
+
+ /* Clean up. */
+ return err;
+}
+
+/* Checks on the instructions within blocks. Currently checks that each
+ block starts with a basic block note, and that basic block notes and
+ control flow jumps are not found in the middle of the block. */
+
+static int
+rtl_verify_bb_insns (void)
+{
+ rtx x;
+ int err = 0;
+ basic_block bb;
+
+ FOR_EACH_BB_REVERSE_FN (bb, cfun)
+ {
+ /* Now check the header of basic
+ block. It ought to contain optional CODE_LABEL followed
+ by NOTE_BASIC_BLOCK. */
+ x = BB_HEAD (bb);
+ if (LABEL_P (x))
+ {
+ if (BB_END (bb) == x)
+ {
+ error ("NOTE_INSN_BASIC_BLOCK is missing for block %d",
+ bb->index);
+ err = 1;
+ }
+
+ x = NEXT_INSN (x);
+ }
+
+ if (!NOTE_INSN_BASIC_BLOCK_P (x) || NOTE_BASIC_BLOCK (x) != bb)
+ {
+ error ("NOTE_INSN_BASIC_BLOCK is missing for block %d",
+ bb->index);
+ err = 1;
+ }
+
+ if (BB_END (bb) == x)
+ /* Do checks for empty blocks here. */
+ ;
+ else
+ for (x = NEXT_INSN (x); x; x = NEXT_INSN (x))
+ {
+ if (NOTE_INSN_BASIC_BLOCK_P (x))
+ {
+ error ("NOTE_INSN_BASIC_BLOCK %d in middle of basic block %d",
+ INSN_UID (x), bb->index);
+ err = 1;
+ }
+
+ if (x == BB_END (bb))
+ break;
+
+ if (control_flow_insn_p (x))
+ {
+ error ("in basic block %d:", bb->index);
+ fatal_insn ("flow control insn inside a basic block", x);
+ }
+ }
+ }
+
+ /* Clean up. */
+ return err;
+}
+
+/* Verify that block pointers for instructions in basic blocks, headers and
+ footers are set appropriately. */
+
+static int
+rtl_verify_bb_pointers (void)
+{
+ int err = 0;
+ basic_block bb;
+
+ /* Check the general integrity of the basic blocks. */
+ FOR_EACH_BB_REVERSE_FN (bb, cfun)
+ {
+ rtx insn;
+
+ if (!(bb->flags & BB_RTL))
+ {
+ error ("BB_RTL flag not set for block %d", bb->index);
+ err = 1;
+ }
+
+ FOR_BB_INSNS (bb, insn)
+ if (BLOCK_FOR_INSN (insn) != bb)
+ {
+ error ("insn %d basic block pointer is %d, should be %d",
+ INSN_UID (insn),
+ BLOCK_FOR_INSN (insn) ? BLOCK_FOR_INSN (insn)->index : 0,
+ bb->index);
+ err = 1;
+ }
+
+ for (insn = BB_HEADER (bb); insn; insn = NEXT_INSN (insn))
+ if (!BARRIER_P (insn)
+ && BLOCK_FOR_INSN (insn) != NULL)
+ {
+ error ("insn %d in header of bb %d has non-NULL basic block",
+ INSN_UID (insn), bb->index);
+ err = 1;
+ }
+ for (insn = BB_FOOTER (bb); insn; insn = NEXT_INSN (insn))
+ if (!BARRIER_P (insn)
+ && BLOCK_FOR_INSN (insn) != NULL)
+ {
+ error ("insn %d in footer of bb %d has non-NULL basic block",
+ INSN_UID (insn), bb->index);
+ err = 1;
+ }
+ }
+
+ /* Clean up. */
+ return err;
+}
+
+/* Verify the CFG and RTL consistency common for both underlying RTL and
+ cfglayout RTL.
+
+ Currently it does following checks:
+
+ - overlapping of basic blocks
+ - insns with wrong BLOCK_FOR_INSN pointers
+ - headers of basic blocks (the NOTE_INSN_BASIC_BLOCK note)
+ - tails of basic blocks (ensure that boundary is necessary)
+ - scans body of the basic block for JUMP_INSN, CODE_LABEL
+ and NOTE_INSN_BASIC_BLOCK
+ - verify that no fall_thru edge crosses hot/cold partition boundaries
+ - verify that there are no pending RTL branch predictions
+ - verify that hot blocks are not dominated by cold blocks
+
+ In future it can be extended check a lot of other stuff as well
+ (reachability of basic blocks, life information, etc. etc.). */
+
+static int
+rtl_verify_flow_info_1 (void)
+{
+ int err = 0;
+
+ err |= rtl_verify_bb_pointers ();
+
+ err |= rtl_verify_bb_insns ();
+
+ err |= rtl_verify_edges ();
+
+ return err;
+}
+
+/* Walk the instruction chain and verify that bb head/end pointers
+ are correct, and that instructions are in exactly one bb and have
+ correct block pointers. */
+
+static int
+rtl_verify_bb_insn_chain (void)
+{
+ basic_block bb;
+ int err = 0;
+ rtx x;
+ rtx last_head = get_last_insn ();
+ basic_block *bb_info;
+ const int max_uid = get_max_uid ();
+
+ bb_info = XCNEWVEC (basic_block, max_uid);
+
+ FOR_EACH_BB_REVERSE_FN (bb, cfun)
+ {
+ rtx head = BB_HEAD (bb);
+ rtx end = BB_END (bb);
+
+ for (x = last_head; x != NULL_RTX; x = PREV_INSN (x))
+ {
+ /* Verify the end of the basic block is in the INSN chain. */
+ if (x == end)
+ break;
+
+ /* And that the code outside of basic blocks has NULL bb field. */
+ if (!BARRIER_P (x)
+ && BLOCK_FOR_INSN (x) != NULL)
+ {
+ error ("insn %d outside of basic blocks has non-NULL bb field",
+ INSN_UID (x));
+ err = 1;
+ }
+ }
+
+ if (!x)
+ {
+ error ("end insn %d for block %d not found in the insn stream",
+ INSN_UID (end), bb->index);
+ err = 1;
+ }
+
+ /* Work backwards from the end to the head of the basic block
+ to verify the head is in the RTL chain. */
+ for (; x != NULL_RTX; x = PREV_INSN (x))
+ {
+ /* While walking over the insn chain, verify insns appear
+ in only one basic block. */
+ if (bb_info[INSN_UID (x)] != NULL)
+ {
+ error ("insn %d is in multiple basic blocks (%d and %d)",
+ INSN_UID (x), bb->index, bb_info[INSN_UID (x)]->index);
+ err = 1;
+ }
+
+ bb_info[INSN_UID (x)] = bb;
+
+ if (x == head)
+ break;
+ }
+ if (!x)
+ {
+ error ("head insn %d for block %d not found in the insn stream",
+ INSN_UID (head), bb->index);
+ err = 1;
+ }
+
+ last_head = PREV_INSN (x);
+ }
+
+ for (x = last_head; x != NULL_RTX; x = PREV_INSN (x))
+ {
+ /* Check that the code before the first basic block has NULL
+ bb field. */
+ if (!BARRIER_P (x)
+ && BLOCK_FOR_INSN (x) != NULL)
+ {
+ error ("insn %d outside of basic blocks has non-NULL bb field",
+ INSN_UID (x));
+ err = 1;
+ }
+ }
+ free (bb_info);
+
+ return err;
+}
+
+/* Verify that fallthru edges point to adjacent blocks in layout order and
+ that barriers exist after non-fallthru blocks. */
+
+static int
+rtl_verify_fallthru (void)
+{
+ basic_block bb;
+ int err = 0;
+
+ FOR_EACH_BB_REVERSE_FN (bb, cfun)
+ {
+ edge e;
+
+ e = find_fallthru_edge (bb->succs);
+ if (!e)
+ {
+ rtx insn;
+
+ /* Ensure existence of barrier in BB with no fallthru edges. */
+ for (insn = NEXT_INSN (BB_END (bb)); ; insn = NEXT_INSN (insn))
+ {
+ if (!insn || NOTE_INSN_BASIC_BLOCK_P (insn))
+ {
+ error ("missing barrier after block %i", bb->index);
+ err = 1;
+ break;
+ }
+ if (BARRIER_P (insn))
+ break;
+ }
+ }
+ else if (e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun)
+ && e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun))
+ {
+ rtx insn;
+
+ if (e->src->next_bb != e->dest)
+ {
+ error
+ ("verify_flow_info: Incorrect blocks for fallthru %i->%i",
+ e->src->index, e->dest->index);
+ err = 1;
+ }
+ else
+ for (insn = NEXT_INSN (BB_END (e->src)); insn != BB_HEAD (e->dest);
+ insn = NEXT_INSN (insn))
+ if (BARRIER_P (insn) || INSN_P (insn))
+ {
+ error ("verify_flow_info: Incorrect fallthru %i->%i",
+ e->src->index, e->dest->index);
+ fatal_insn ("wrong insn in the fallthru edge", insn);
+ err = 1;
+ }
+ }
+ }
+
+ return err;
+}
+
+/* Verify that blocks are laid out in consecutive order. While walking the
+ instructions, verify that all expected instructions are inside the basic
+ blocks, and that all returns are followed by barriers. */
+
+static int
+rtl_verify_bb_layout (void)
+{
+ basic_block bb;
+ int err = 0;
+ rtx x;
+ int num_bb_notes;
+ const rtx rtx_first = get_insns ();
+ basic_block last_bb_seen = ENTRY_BLOCK_PTR_FOR_FN (cfun), curr_bb = NULL;
+
+ num_bb_notes = 0;
+ last_bb_seen = ENTRY_BLOCK_PTR_FOR_FN (cfun);
+
+ for (x = rtx_first; x; x = NEXT_INSN (x))
+ {
+ if (NOTE_INSN_BASIC_BLOCK_P (x))
+ {
+ bb = NOTE_BASIC_BLOCK (x);
+
+ num_bb_notes++;
+ if (bb != last_bb_seen->next_bb)
+ internal_error ("basic blocks not laid down consecutively");
+
+ curr_bb = last_bb_seen = bb;
+ }
+
+ if (!curr_bb)
+ {
+ switch (GET_CODE (x))
+ {
+ case BARRIER:
+ case NOTE:
+ break;
+
+ case CODE_LABEL:
+ /* An ADDR_VEC is placed outside any basic block. */
+ if (NEXT_INSN (x)
+ && JUMP_TABLE_DATA_P (NEXT_INSN (x)))
+ x = NEXT_INSN (x);
+
+ /* But in any case, non-deletable labels can appear anywhere. */
+ break;
+
+ default:
+ fatal_insn ("insn outside basic block", x);
+ }
+ }
+
+ if (JUMP_P (x)
+ && returnjump_p (x) && ! condjump_p (x)
+ && ! (next_nonnote_insn (x) && BARRIER_P (next_nonnote_insn (x))))
+ fatal_insn ("return not followed by barrier", x);
+
+ if (curr_bb && x == BB_END (curr_bb))
+ curr_bb = NULL;
+ }
+
+ if (num_bb_notes != n_basic_blocks_for_fn (cfun) - NUM_FIXED_BLOCKS)
+ internal_error
+ ("number of bb notes in insn chain (%d) != n_basic_blocks (%d)",
+ num_bb_notes, n_basic_blocks_for_fn (cfun));
+
+ return err;
+}
+
+/* Verify the CFG and RTL consistency common for both underlying RTL and
+ cfglayout RTL, plus consistency checks specific to linearized RTL mode.
+
+ Currently it does following checks:
+ - all checks of rtl_verify_flow_info_1
+ - test head/end pointers
+ - check that blocks are laid out in consecutive order
+ - check that all insns are in the basic blocks
+ (except the switch handling code, barriers and notes)
+ - check that all returns are followed by barriers
+ - check that all fallthru edge points to the adjacent blocks
+ - verify that there is a single hot/cold partition boundary after bbro */
+
+static int
+rtl_verify_flow_info (void)
+{
+ int err = 0;
+
+ err |= rtl_verify_flow_info_1 ();
+
+ err |= rtl_verify_bb_insn_chain ();
+
+ err |= rtl_verify_fallthru ();
+
+ err |= rtl_verify_bb_layout ();
+
+ err |= verify_hot_cold_block_grouping ();
+
+ return err;
+}
+
+/* Assume that the preceding pass has possibly eliminated jump instructions
+ or converted the unconditional jumps. Eliminate the edges from CFG.
+ Return true if any edges are eliminated. */
+
+bool
+purge_dead_edges (basic_block bb)
+{
+ edge e;
+ rtx insn = BB_END (bb), note;
+ bool purged = false;
+ bool found;
+ edge_iterator ei;
+
+ if (DEBUG_INSN_P (insn) && insn != BB_HEAD (bb))
+ do
+ insn = PREV_INSN (insn);
+ while ((DEBUG_INSN_P (insn) || NOTE_P (insn)) && insn != BB_HEAD (bb));
+
+ /* If this instruction cannot trap, remove REG_EH_REGION notes. */
+ if (NONJUMP_INSN_P (insn)
+ && (note = find_reg_note (insn, REG_EH_REGION, NULL)))
+ {
+ rtx eqnote;
+
+ if (! may_trap_p (PATTERN (insn))
+ || ((eqnote = find_reg_equal_equiv_note (insn))
+ && ! may_trap_p (XEXP (eqnote, 0))))
+ remove_note (insn, note);
+ }
+
+ /* Cleanup abnormal edges caused by exceptions or non-local gotos. */
+ for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
+ {
+ bool remove = false;
+
+ /* There are three types of edges we need to handle correctly here: EH
+ edges, abnormal call EH edges, and abnormal call non-EH edges. The
+ latter can appear when nonlocal gotos are used. */
+ if (e->flags & EDGE_ABNORMAL_CALL)
+ {
+ if (!CALL_P (insn))
+ remove = true;
+ else if (can_nonlocal_goto (insn))
+ ;
+ else if ((e->flags & EDGE_EH) && can_throw_internal (insn))
+ ;
+ else if (flag_tm && find_reg_note (insn, REG_TM, NULL))
+ ;
+ else
+ remove = true;
+ }
+ else if (e->flags & EDGE_EH)
+ remove = !can_throw_internal (insn);
+
+ if (remove)
+ {
+ remove_edge (e);
+ df_set_bb_dirty (bb);
+ purged = true;
+ }
+ else
+ ei_next (&ei);
+ }
+
+ if (JUMP_P (insn))
+ {
+ rtx note;
+ edge b,f;
+ edge_iterator ei;
+
+ /* We do care only about conditional jumps and simplejumps. */
+ if (!any_condjump_p (insn)
+ && !returnjump_p (insn)
+ && !simplejump_p (insn))
+ return purged;
+
+ /* Branch probability/prediction notes are defined only for
+ condjumps. We've possibly turned condjump into simplejump. */
+ if (simplejump_p (insn))
+ {
+ note = find_reg_note (insn, REG_BR_PROB, NULL);
+ if (note)
+ remove_note (insn, note);
+ while ((note = find_reg_note (insn, REG_BR_PRED, NULL)))
+ remove_note (insn, note);
+ }
+
+ for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
+ {
+ /* Avoid abnormal flags to leak from computed jumps turned
+ into simplejumps. */
+
+ e->flags &= ~EDGE_ABNORMAL;
+
+ /* See if this edge is one we should keep. */
+ if ((e->flags & EDGE_FALLTHRU) && any_condjump_p (insn))
+ /* A conditional jump can fall through into the next
+ block, so we should keep the edge. */
+ {
+ ei_next (&ei);
+ continue;
+ }
+ else if (e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)
+ && BB_HEAD (e->dest) == JUMP_LABEL (insn))
+ /* If the destination block is the target of the jump,
+ keep the edge. */
+ {
+ ei_next (&ei);
+ continue;
+ }
+ else if (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun)
+ && returnjump_p (insn))
+ /* If the destination block is the exit block, and this
+ instruction is a return, then keep the edge. */
+ {
+ ei_next (&ei);
+ continue;
+ }
+ else if ((e->flags & EDGE_EH) && can_throw_internal (insn))
+ /* Keep the edges that correspond to exceptions thrown by
+ this instruction and rematerialize the EDGE_ABNORMAL
+ flag we just cleared above. */
+ {
+ e->flags |= EDGE_ABNORMAL;
+ ei_next (&ei);
+ continue;
+ }
+
+ /* We do not need this edge. */
+ df_set_bb_dirty (bb);
+ purged = true;
+ remove_edge (e);
+ }
+
+ if (EDGE_COUNT (bb->succs) == 0 || !purged)
+ return purged;
+
+ if (dump_file)
+ fprintf (dump_file, "Purged edges from bb %i\n", bb->index);
+
+ if (!optimize)
+ return purged;
+
+ /* Redistribute probabilities. */
+ if (single_succ_p (bb))
+ {
+ single_succ_edge (bb)->probability = REG_BR_PROB_BASE;
+ single_succ_edge (bb)->count = bb->count;
+ }
+ else
+ {
+ note = find_reg_note (insn, REG_BR_PROB, NULL);
+ if (!note)
+ return purged;
+
+ b = BRANCH_EDGE (bb);
+ f = FALLTHRU_EDGE (bb);
+ b->probability = XINT (note, 0);
+ f->probability = REG_BR_PROB_BASE - b->probability;
+ /* Update these to use GCOV_COMPUTE_SCALE. */
+ b->count = bb->count * b->probability / REG_BR_PROB_BASE;
+ f->count = bb->count * f->probability / REG_BR_PROB_BASE;
+ }
+
+ return purged;
+ }
+ else if (CALL_P (insn) && SIBLING_CALL_P (insn))
+ {
+ /* First, there should not be any EH or ABCALL edges resulting
+ from non-local gotos and the like. If there were, we shouldn't
+ have created the sibcall in the first place. Second, there
+ should of course never have been a fallthru edge. */
+ gcc_assert (single_succ_p (bb));
+ gcc_assert (single_succ_edge (bb)->flags
+ == (EDGE_SIBCALL | EDGE_ABNORMAL));
+
+ return 0;
+ }
+
+ /* If we don't see a jump insn, we don't know exactly why the block would
+ have been broken at this point. Look for a simple, non-fallthru edge,
+ as these are only created by conditional branches. If we find such an
+ edge we know that there used to be a jump here and can then safely
+ remove all non-fallthru edges. */
+ found = false;
+ FOR_EACH_EDGE (e, ei, bb->succs)
+ if (! (e->flags & (EDGE_COMPLEX | EDGE_FALLTHRU)))
+ {
+ found = true;
+ break;
+ }
+
+ if (!found)
+ return purged;
+
+ /* Remove all but the fake and fallthru edges. The fake edge may be
+ the only successor for this block in the case of noreturn
+ calls. */
+ for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
+ {
+ if (!(e->flags & (EDGE_FALLTHRU | EDGE_FAKE)))
+ {
+ df_set_bb_dirty (bb);
+ remove_edge (e);
+ purged = true;
+ }
+ else
+ ei_next (&ei);
+ }
+
+ gcc_assert (single_succ_p (bb));
+
+ single_succ_edge (bb)->probability = REG_BR_PROB_BASE;
+ single_succ_edge (bb)->count = bb->count;
+
+ if (dump_file)
+ fprintf (dump_file, "Purged non-fallthru edges from bb %i\n",
+ bb->index);
+ return purged;
+}
+
+/* Search all basic blocks for potentially dead edges and purge them. Return
+ true if some edge has been eliminated. */
+
+bool
+purge_all_dead_edges (void)
+{
+ int purged = false;
+ basic_block bb;
+
+ FOR_EACH_BB_FN (bb, cfun)
+ {
+ bool purged_here = purge_dead_edges (bb);
+
+ purged |= purged_here;
+ }
+
+ return purged;
+}
+
+/* This is used by a few passes that emit some instructions after abnormal
+ calls, moving the basic block's end, while they in fact do want to emit
+ them on the fallthru edge. Look for abnormal call edges, find backward
+ the call in the block and insert the instructions on the edge instead.
+
+ Similarly, handle instructions throwing exceptions internally.
+
+ Return true when instructions have been found and inserted on edges. */
+
+bool
+fixup_abnormal_edges (void)
+{
+ bool inserted = false;
+ basic_block bb;
+
+ FOR_EACH_BB_FN (bb, cfun)
+ {
+ edge e;
+ edge_iterator ei;
+
+ /* Look for cases we are interested in - calls or instructions causing
+ exceptions. */
+ FOR_EACH_EDGE (e, ei, bb->succs)
+ if ((e->flags & EDGE_ABNORMAL_CALL)
+ || ((e->flags & (EDGE_ABNORMAL | EDGE_EH))
+ == (EDGE_ABNORMAL | EDGE_EH)))
+ break;
+
+ if (e && !CALL_P (BB_END (bb)) && !can_throw_internal (BB_END (bb)))
+ {
+ rtx insn;
+
+ /* Get past the new insns generated. Allow notes, as the insns
+ may be already deleted. */
+ insn = BB_END (bb);
+ while ((NONJUMP_INSN_P (insn) || NOTE_P (insn))
+ && !can_throw_internal (insn)
+ && insn != BB_HEAD (bb))
+ insn = PREV_INSN (insn);
+
+ if (CALL_P (insn) || can_throw_internal (insn))
+ {
+ rtx stop, next;
+
+ e = find_fallthru_edge (bb->succs);
+
+ stop = NEXT_INSN (BB_END (bb));
+ BB_END (bb) = insn;
+
+ for (insn = NEXT_INSN (insn); insn != stop; insn = next)
+ {
+ next = NEXT_INSN (insn);
+ if (INSN_P (insn))
+ {
+ delete_insn (insn);
+
+ /* Sometimes there's still the return value USE.
+ If it's placed after a trapping call (i.e. that
+ call is the last insn anyway), we have no fallthru
+ edge. Simply delete this use and don't try to insert
+ on the non-existent edge. */
+ if (GET_CODE (PATTERN (insn)) != USE)
+ {
+ /* We're not deleting it, we're moving it. */
+ INSN_DELETED_P (insn) = 0;
+ PREV_INSN (insn) = NULL_RTX;
+ NEXT_INSN (insn) = NULL_RTX;
+
+ insert_insn_on_edge (insn, e);
+ inserted = true;
+ }
+ }
+ else if (!BARRIER_P (insn))
+ set_block_for_insn (insn, NULL);
+ }
+ }
+
+ /* It may be that we don't find any trapping insn. In this
+ case we discovered quite late that the insn that had been
+ marked as can_throw_internal in fact couldn't trap at all.
+ So we should in fact delete the EH edges out of the block. */
+ else
+ purge_dead_edges (bb);
+ }
+ }
+
+ return inserted;
+}
+
+/* Cut the insns from FIRST to LAST out of the insns stream. */
+
+rtx
+unlink_insn_chain (rtx first, rtx last)
+{
+ rtx prevfirst = PREV_INSN (first);
+ rtx nextlast = NEXT_INSN (last);
+
+ PREV_INSN (first) = NULL;
+ NEXT_INSN (last) = NULL;
+ if (prevfirst)
+ NEXT_INSN (prevfirst) = nextlast;
+ if (nextlast)
+ PREV_INSN (nextlast) = prevfirst;
+ else
+ set_last_insn (prevfirst);
+ if (!prevfirst)
+ set_first_insn (nextlast);
+ return first;
+}
+
+/* Skip over inter-block insns occurring after BB which are typically
+ associated with BB (e.g., barriers). If there are any such insns,
+ we return the last one. Otherwise, we return the end of BB. */
+
+static rtx
+skip_insns_after_block (basic_block bb)
+{
+ rtx insn, last_insn, next_head, prev;
+
+ next_head = NULL_RTX;
+ if (bb->next_bb != EXIT_BLOCK_PTR_FOR_FN (cfun))
+ next_head = BB_HEAD (bb->next_bb);
+
+ for (last_insn = insn = BB_END (bb); (insn = NEXT_INSN (insn)) != 0; )
+ {
+ if (insn == next_head)
+ break;
+
+ switch (GET_CODE (insn))
+ {
+ case BARRIER:
+ last_insn = insn;
+ continue;
+
+ case NOTE:
+ switch (NOTE_KIND (insn))
+ {
+ case NOTE_INSN_BLOCK_END:
+ gcc_unreachable ();
+ continue;
+ default:
+ continue;
+ break;
+ }
+ break;
+
+ case CODE_LABEL:
+ if (NEXT_INSN (insn)
+ && JUMP_TABLE_DATA_P (NEXT_INSN (insn)))
+ {
+ insn = NEXT_INSN (insn);
+ last_insn = insn;
+ continue;
+ }
+ break;
+
+ default:
+ break;
+ }
+
+ break;
+ }
+
+ /* It is possible to hit contradictory sequence. For instance:
+
+ jump_insn
+ NOTE_INSN_BLOCK_BEG
+ barrier
+
+ Where barrier belongs to jump_insn, but the note does not. This can be
+ created by removing the basic block originally following
+ NOTE_INSN_BLOCK_BEG. In such case reorder the notes. */
+
+ for (insn = last_insn; insn != BB_END (bb); insn = prev)
+ {
+ prev = PREV_INSN (insn);
+ if (NOTE_P (insn))
+ switch (NOTE_KIND (insn))
+ {
+ case NOTE_INSN_BLOCK_END:
+ gcc_unreachable ();
+ break;
+ case NOTE_INSN_DELETED:
+ case NOTE_INSN_DELETED_LABEL:
+ case NOTE_INSN_DELETED_DEBUG_LABEL:
+ continue;
+ default:
+ reorder_insns (insn, insn, last_insn);
+ }
+ }
+
+ return last_insn;
+}
+
+/* Locate or create a label for a given basic block. */
+
+static rtx
+label_for_bb (basic_block bb)
+{
+ rtx label = BB_HEAD (bb);
+
+ if (!LABEL_P (label))
+ {
+ if (dump_file)
+ fprintf (dump_file, "Emitting label for block %d\n", bb->index);
+
+ label = block_label (bb);
+ }
+
+ return label;
+}
+
+/* Locate the effective beginning and end of the insn chain for each
+ block, as defined by skip_insns_after_block above. */
+
+static void
+record_effective_endpoints (void)
+{
+ rtx next_insn;
+ basic_block bb;
+ rtx insn;
+
+ for (insn = get_insns ();
+ insn
+ && NOTE_P (insn)
+ && NOTE_KIND (insn) != NOTE_INSN_BASIC_BLOCK;
+ insn = NEXT_INSN (insn))
+ continue;
+ /* No basic blocks at all? */
+ gcc_assert (insn);
+
+ if (PREV_INSN (insn))
+ cfg_layout_function_header =
+ unlink_insn_chain (get_insns (), PREV_INSN (insn));
+ else
+ cfg_layout_function_header = NULL_RTX;
+
+ next_insn = get_insns ();
+ FOR_EACH_BB_FN (bb, cfun)
+ {
+ rtx end;
+
+ if (PREV_INSN (BB_HEAD (bb)) && next_insn != BB_HEAD (bb))
+ BB_HEADER (bb) = unlink_insn_chain (next_insn,
+ PREV_INSN (BB_HEAD (bb)));
+ end = skip_insns_after_block (bb);
+ if (NEXT_INSN (BB_END (bb)) && BB_END (bb) != end)
+ BB_FOOTER (bb) = unlink_insn_chain (NEXT_INSN (BB_END (bb)), end);
+ next_insn = NEXT_INSN (BB_END (bb));
+ }
+
+ cfg_layout_function_footer = next_insn;
+ if (cfg_layout_function_footer)
+ cfg_layout_function_footer = unlink_insn_chain (cfg_layout_function_footer, get_last_insn ());
+}
+
+static unsigned int
+into_cfg_layout_mode (void)
+{
+ cfg_layout_initialize (0);
+ return 0;
+}
+
+static unsigned int
+outof_cfg_layout_mode (void)
+{
+ basic_block bb;
+
+ FOR_EACH_BB_FN (bb, cfun)
+ if (bb->next_bb != EXIT_BLOCK_PTR_FOR_FN (cfun))
+ bb->aux = bb->next_bb;
+
+ cfg_layout_finalize ();
+
+ return 0;
+}
+
+namespace {
+
+const pass_data pass_data_into_cfg_layout_mode =
+{
+ RTL_PASS, /* type */
+ "into_cfglayout", /* name */
+ OPTGROUP_NONE, /* optinfo_flags */
+ false, /* has_gate */
+ true, /* has_execute */
+ TV_CFG, /* tv_id */
+ 0, /* properties_required */
+ PROP_cfglayout, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ 0, /* todo_flags_finish */
+};
+
+class pass_into_cfg_layout_mode : public rtl_opt_pass
+{
+public:
+ pass_into_cfg_layout_mode (gcc::context *ctxt)
+ : rtl_opt_pass (pass_data_into_cfg_layout_mode, ctxt)
+ {}
+
+ /* opt_pass methods: */
+ unsigned int execute () { return into_cfg_layout_mode (); }
+
+}; // class pass_into_cfg_layout_mode
+
+} // anon namespace
+
+rtl_opt_pass *
+make_pass_into_cfg_layout_mode (gcc::context *ctxt)
+{
+ return new pass_into_cfg_layout_mode (ctxt);
+}
+
+namespace {
+
+const pass_data pass_data_outof_cfg_layout_mode =
+{
+ RTL_PASS, /* type */
+ "outof_cfglayout", /* name */
+ OPTGROUP_NONE, /* optinfo_flags */
+ false, /* has_gate */
+ true, /* has_execute */
+ TV_CFG, /* tv_id */
+ 0, /* properties_required */
+ 0, /* properties_provided */
+ PROP_cfglayout, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ 0, /* todo_flags_finish */
+};
+
+class pass_outof_cfg_layout_mode : public rtl_opt_pass
+{
+public:
+ pass_outof_cfg_layout_mode (gcc::context *ctxt)
+ : rtl_opt_pass (pass_data_outof_cfg_layout_mode, ctxt)
+ {}
+
+ /* opt_pass methods: */
+ unsigned int execute () { return outof_cfg_layout_mode (); }
+
+}; // class pass_outof_cfg_layout_mode
+
+} // anon namespace
+
+rtl_opt_pass *
+make_pass_outof_cfg_layout_mode (gcc::context *ctxt)
+{
+ return new pass_outof_cfg_layout_mode (ctxt);
+}
+
+
+/* Link the basic blocks in the correct order, compacting the basic
+ block queue while at it. If STAY_IN_CFGLAYOUT_MODE is false, this
+ function also clears the basic block header and footer fields.
+
+ This function is usually called after a pass (e.g. tracer) finishes
+ some transformations while in cfglayout mode. The required sequence
+ of the basic blocks is in a linked list along the bb->aux field.
+ This functions re-links the basic block prev_bb and next_bb pointers
+ accordingly, and it compacts and renumbers the blocks.
+
+ FIXME: This currently works only for RTL, but the only RTL-specific
+ bits are the STAY_IN_CFGLAYOUT_MODE bits. The tracer pass was moved
+ to GIMPLE a long time ago, but it doesn't relink the basic block
+ chain. It could do that (to give better initial RTL) if this function
+ is made IR-agnostic (and moved to cfganal.c or cfg.c while at it). */
+
+void
+relink_block_chain (bool stay_in_cfglayout_mode)
+{
+ basic_block bb, prev_bb;
+ int index;
+
+ /* Maybe dump the re-ordered sequence. */
+ if (dump_file)
+ {
+ fprintf (dump_file, "Reordered sequence:\n");
+ for (bb = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb, index =
+ NUM_FIXED_BLOCKS;
+ bb;
+ bb = (basic_block) bb->aux, index++)
+ {
+ fprintf (dump_file, " %i ", index);
+ if (get_bb_original (bb))
+ fprintf (dump_file, "duplicate of %i ",
+ get_bb_original (bb)->index);
+ else if (forwarder_block_p (bb)
+ && !LABEL_P (BB_HEAD (bb)))
+ fprintf (dump_file, "compensation ");
+ else
+ fprintf (dump_file, "bb %i ", bb->index);
+ fprintf (dump_file, " [%i]\n", bb->frequency);
+ }
+ }
+
+ /* Now reorder the blocks. */
+ prev_bb = ENTRY_BLOCK_PTR_FOR_FN (cfun);
+ bb = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb;
+ for (; bb; prev_bb = bb, bb = (basic_block) bb->aux)
+ {
+ bb->prev_bb = prev_bb;
+ prev_bb->next_bb = bb;
+ }
+ prev_bb->next_bb = EXIT_BLOCK_PTR_FOR_FN (cfun);
+ EXIT_BLOCK_PTR_FOR_FN (cfun)->prev_bb = prev_bb;
+
+ /* Then, clean up the aux fields. */
+ FOR_ALL_BB_FN (bb, cfun)
+ {
+ bb->aux = NULL;
+ if (!stay_in_cfglayout_mode)
+ BB_HEADER (bb) = BB_FOOTER (bb) = NULL;
+ }
+
+ /* Maybe reset the original copy tables, they are not valid anymore
+ when we renumber the basic blocks in compact_blocks. If we are
+ are going out of cfglayout mode, don't re-allocate the tables. */
+ free_original_copy_tables ();
+ if (stay_in_cfglayout_mode)
+ initialize_original_copy_tables ();
+
+ /* Finally, put basic_block_info in the new order. */
+ compact_blocks ();
+}
+
+
+/* Given a reorder chain, rearrange the code to match. */
+
+static void
+fixup_reorder_chain (void)
+{
+ basic_block bb;
+ rtx insn = NULL;
+
+ if (cfg_layout_function_header)
+ {
+ set_first_insn (cfg_layout_function_header);
+ insn = cfg_layout_function_header;
+ while (NEXT_INSN (insn))
+ insn = NEXT_INSN (insn);
+ }
+
+ /* First do the bulk reordering -- rechain the blocks without regard to
+ the needed changes to jumps and labels. */
+
+ for (bb = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb; bb; bb = (basic_block)
+ bb->aux)
+ {
+ if (BB_HEADER (bb))
+ {
+ if (insn)
+ NEXT_INSN (insn) = BB_HEADER (bb);
+ else
+ set_first_insn (BB_HEADER (bb));
+ PREV_INSN (BB_HEADER (bb)) = insn;
+ insn = BB_HEADER (bb);
+ while (NEXT_INSN (insn))
+ insn = NEXT_INSN (insn);
+ }
+ if (insn)
+ NEXT_INSN (insn) = BB_HEAD (bb);
+ else
+ set_first_insn (BB_HEAD (bb));
+ PREV_INSN (BB_HEAD (bb)) = insn;
+ insn = BB_END (bb);
+ if (BB_FOOTER (bb))
+ {
+ NEXT_INSN (insn) = BB_FOOTER (bb);
+ PREV_INSN (BB_FOOTER (bb)) = insn;
+ while (NEXT_INSN (insn))
+ insn = NEXT_INSN (insn);
+ }
+ }
+
+ NEXT_INSN (insn) = cfg_layout_function_footer;
+ if (cfg_layout_function_footer)
+ PREV_INSN (cfg_layout_function_footer) = insn;
+
+ while (NEXT_INSN (insn))
+ insn = NEXT_INSN (insn);
+
+ set_last_insn (insn);
+#ifdef ENABLE_CHECKING
+ verify_insn_chain ();
+#endif
+
+ /* Now add jumps and labels as needed to match the blocks new
+ outgoing edges. */
+
+ for (bb = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb; bb ; bb = (basic_block)
+ bb->aux)
+ {
+ edge e_fall, e_taken, e;
+ rtx bb_end_insn;
+ rtx ret_label = NULL_RTX;
+ basic_block nb;
+ edge_iterator ei;
+
+ if (EDGE_COUNT (bb->succs) == 0)
+ continue;
+
+ /* Find the old fallthru edge, and another non-EH edge for
+ a taken jump. */
+ e_taken = e_fall = NULL;
+
+ FOR_EACH_EDGE (e, ei, bb->succs)
+ if (e->flags & EDGE_FALLTHRU)
+ e_fall = e;
+ else if (! (e->flags & EDGE_EH))
+ e_taken = e;
+
+ bb_end_insn = BB_END (bb);
+ if (JUMP_P (bb_end_insn))
+ {
+ ret_label = JUMP_LABEL (bb_end_insn);
+ if (any_condjump_p (bb_end_insn))
+ {
+ /* This might happen if the conditional jump has side
+ effects and could therefore not be optimized away.
+ Make the basic block to end with a barrier in order
+ to prevent rtl_verify_flow_info from complaining. */
+ if (!e_fall)
+ {
+ gcc_assert (!onlyjump_p (bb_end_insn)
+ || returnjump_p (bb_end_insn)
+ || (e_taken->flags & EDGE_CROSSING));
+ emit_barrier_after (bb_end_insn);
+ continue;
+ }
+
+ /* If the old fallthru is still next, nothing to do. */
+ if (bb->aux == e_fall->dest
+ || e_fall->dest == EXIT_BLOCK_PTR_FOR_FN (cfun))
+ continue;
+
+ /* The degenerated case of conditional jump jumping to the next
+ instruction can happen for jumps with side effects. We need
+ to construct a forwarder block and this will be done just
+ fine by force_nonfallthru below. */
+ if (!e_taken)
+ ;
+
+ /* There is another special case: if *neither* block is next,
+ such as happens at the very end of a function, then we'll
+ need to add a new unconditional jump. Choose the taken
+ edge based on known or assumed probability. */
+ else if (bb->aux != e_taken->dest)
+ {
+ rtx note = find_reg_note (bb_end_insn, REG_BR_PROB, 0);
+
+ if (note
+ && XINT (note, 0) < REG_BR_PROB_BASE / 2
+ && invert_jump (bb_end_insn,
+ (e_fall->dest
+ == EXIT_BLOCK_PTR_FOR_FN (cfun)
+ ? NULL_RTX
+ : label_for_bb (e_fall->dest)), 0))
+ {
+ e_fall->flags &= ~EDGE_FALLTHRU;
+ gcc_checking_assert (could_fall_through
+ (e_taken->src, e_taken->dest));
+ e_taken->flags |= EDGE_FALLTHRU;
+ update_br_prob_note (bb);
+ e = e_fall, e_fall = e_taken, e_taken = e;
+ }
+ }
+
+ /* If the "jumping" edge is a crossing edge, and the fall
+ through edge is non-crossing, leave things as they are. */
+ else if ((e_taken->flags & EDGE_CROSSING)
+ && !(e_fall->flags & EDGE_CROSSING))
+ continue;
+
+ /* Otherwise we can try to invert the jump. This will
+ basically never fail, however, keep up the pretense. */
+ else if (invert_jump (bb_end_insn,
+ (e_fall->dest
+ == EXIT_BLOCK_PTR_FOR_FN (cfun)
+ ? NULL_RTX
+ : label_for_bb (e_fall->dest)), 0))
+ {
+ e_fall->flags &= ~EDGE_FALLTHRU;
+ gcc_checking_assert (could_fall_through
+ (e_taken->src, e_taken->dest));
+ e_taken->flags |= EDGE_FALLTHRU;
+ update_br_prob_note (bb);
+ if (LABEL_NUSES (ret_label) == 0
+ && single_pred_p (e_taken->dest))
+ delete_insn (ret_label);
+ continue;
+ }
+ }
+ else if (extract_asm_operands (PATTERN (bb_end_insn)) != NULL)
+ {
+ /* If the old fallthru is still next or if
+ asm goto doesn't have a fallthru (e.g. when followed by
+ __builtin_unreachable ()), nothing to do. */
+ if (! e_fall
+ || bb->aux == e_fall->dest
+ || e_fall->dest == EXIT_BLOCK_PTR_FOR_FN (cfun))
+ continue;
+
+ /* Otherwise we'll have to use the fallthru fixup below. */
+ }
+ else
+ {
+ /* Otherwise we have some return, switch or computed
+ jump. In the 99% case, there should not have been a
+ fallthru edge. */
+ gcc_assert (returnjump_p (bb_end_insn) || !e_fall);
+ continue;
+ }
+ }
+ else
+ {
+ /* No fallthru implies a noreturn function with EH edges, or
+ something similarly bizarre. In any case, we don't need to
+ do anything. */
+ if (! e_fall)
+ continue;
+
+ /* If the fallthru block is still next, nothing to do. */
+ if (bb->aux == e_fall->dest)
+ continue;
+
+ /* A fallthru to exit block. */
+ if (e_fall->dest == EXIT_BLOCK_PTR_FOR_FN (cfun))
+ continue;
+ }
+
+ /* We got here if we need to add a new jump insn.
+ Note force_nonfallthru can delete E_FALL and thus we have to
+ save E_FALL->src prior to the call to force_nonfallthru. */
+ nb = force_nonfallthru_and_redirect (e_fall, e_fall->dest, ret_label);
+ if (nb)
+ {
+ nb->aux = bb->aux;
+ bb->aux = nb;
+ /* Don't process this new block. */
+ bb = nb;
+ }
+ }
+
+ relink_block_chain (/*stay_in_cfglayout_mode=*/false);
+
+ /* Annoying special case - jump around dead jumptables left in the code. */
+ FOR_EACH_BB_FN (bb, cfun)
+ {
+ edge e = find_fallthru_edge (bb->succs);
+
+ if (e && !can_fallthru (e->src, e->dest))
+ force_nonfallthru (e);
+ }
+
+ /* Ensure goto_locus from edges has some instructions with that locus
+ in RTL. */
+ if (!optimize)
+ FOR_EACH_BB_FN (bb, cfun)
+ {
+ edge e;
+ edge_iterator ei;
+
+ FOR_EACH_EDGE (e, ei, bb->succs)
+ if (LOCATION_LOCUS (e->goto_locus) != UNKNOWN_LOCATION
+ && !(e->flags & EDGE_ABNORMAL))
+ {
+ edge e2;
+ edge_iterator ei2;
+ basic_block dest, nb;
+ rtx end;
+
+ insn = BB_END (e->src);
+ end = PREV_INSN (BB_HEAD (e->src));
+ while (insn != end
+ && (!NONDEBUG_INSN_P (insn) || !INSN_HAS_LOCATION (insn)))
+ insn = PREV_INSN (insn);
+ if (insn != end
+ && INSN_LOCATION (insn) == e->goto_locus)
+ continue;
+ if (simplejump_p (BB_END (e->src))
+ && !INSN_HAS_LOCATION (BB_END (e->src)))
+ {
+ INSN_LOCATION (BB_END (e->src)) = e->goto_locus;
+ continue;
+ }
+ dest = e->dest;
+ if (dest == EXIT_BLOCK_PTR_FOR_FN (cfun))
+ {
+ /* Non-fallthru edges to the exit block cannot be split. */
+ if (!(e->flags & EDGE_FALLTHRU))
+ continue;
+ }
+ else
+ {
+ insn = BB_HEAD (dest);
+ end = NEXT_INSN (BB_END (dest));
+ while (insn != end && !NONDEBUG_INSN_P (insn))
+ insn = NEXT_INSN (insn);
+ if (insn != end && INSN_HAS_LOCATION (insn)
+ && INSN_LOCATION (insn) == e->goto_locus)
+ continue;
+ }
+ nb = split_edge (e);
+ if (!INSN_P (BB_END (nb)))
+ BB_END (nb) = emit_insn_after_noloc (gen_nop (), BB_END (nb),
+ nb);
+ INSN_LOCATION (BB_END (nb)) = e->goto_locus;
+
+ /* If there are other incoming edges to the destination block
+ with the same goto locus, redirect them to the new block as
+ well, this can prevent other such blocks from being created
+ in subsequent iterations of the loop. */
+ for (ei2 = ei_start (dest->preds); (e2 = ei_safe_edge (ei2)); )
+ if (LOCATION_LOCUS (e2->goto_locus) != UNKNOWN_LOCATION
+ && !(e2->flags & (EDGE_ABNORMAL | EDGE_FALLTHRU))
+ && e->goto_locus == e2->goto_locus)
+ redirect_edge_and_branch (e2, nb);
+ else
+ ei_next (&ei2);
+ }
+ }
+}
+
+/* Perform sanity checks on the insn chain.
+ 1. Check that next/prev pointers are consistent in both the forward and
+ reverse direction.
+ 2. Count insns in chain, going both directions, and check if equal.
+ 3. Check that get_last_insn () returns the actual end of chain. */
+
+DEBUG_FUNCTION void
+verify_insn_chain (void)
+{
+ rtx x, prevx, nextx;
+ int insn_cnt1, insn_cnt2;
+
+ for (prevx = NULL, insn_cnt1 = 1, x = get_insns ();
+ x != 0;
+ prevx = x, insn_cnt1++, x = NEXT_INSN (x))
+ gcc_assert (PREV_INSN (x) == prevx);
+
+ gcc_assert (prevx == get_last_insn ());
+
+ for (nextx = NULL, insn_cnt2 = 1, x = get_last_insn ();
+ x != 0;
+ nextx = x, insn_cnt2++, x = PREV_INSN (x))
+ gcc_assert (NEXT_INSN (x) == nextx);
+
+ gcc_assert (insn_cnt1 == insn_cnt2);
+}
+
+/* If we have assembler epilogues, the block falling through to exit must
+ be the last one in the reordered chain when we reach final. Ensure
+ that this condition is met. */
+static void
+fixup_fallthru_exit_predecessor (void)
+{
+ edge e;
+ basic_block bb = NULL;
+
+ /* This transformation is not valid before reload, because we might
+ separate a call from the instruction that copies the return
+ value. */
+ gcc_assert (reload_completed);
+
+ e = find_fallthru_edge (EXIT_BLOCK_PTR_FOR_FN (cfun)->preds);
+ if (e)
+ bb = e->src;
+
+ if (bb && bb->aux)
+ {
+ basic_block c = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb;
+
+ /* If the very first block is the one with the fall-through exit
+ edge, we have to split that block. */
+ if (c == bb)
+ {
+ bb = split_block (bb, NULL)->dest;
+ bb->aux = c->aux;
+ c->aux = bb;
+ BB_FOOTER (bb) = BB_FOOTER (c);
+ BB_FOOTER (c) = NULL;
+ }
+
+ while (c->aux != bb)
+ c = (basic_block) c->aux;
+
+ c->aux = bb->aux;
+ while (c->aux)
+ c = (basic_block) c->aux;
+
+ c->aux = bb;
+ bb->aux = NULL;
+ }
+}
+
+/* In case there are more than one fallthru predecessors of exit, force that
+ there is only one. */
+
+static void
+force_one_exit_fallthru (void)
+{
+ edge e, predecessor = NULL;
+ bool more = false;
+ edge_iterator ei;
+ basic_block forwarder, bb;
+
+ FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR_FOR_FN (cfun)->preds)
+ if (e->flags & EDGE_FALLTHRU)
+ {
+ if (predecessor == NULL)
+ predecessor = e;
+ else
+ {
+ more = true;
+ break;
+ }
+ }
+
+ if (!more)
+ return;
+
+ /* Exit has several fallthru predecessors. Create a forwarder block for
+ them. */
+ forwarder = split_edge (predecessor);
+ for (ei = ei_start (EXIT_BLOCK_PTR_FOR_FN (cfun)->preds);
+ (e = ei_safe_edge (ei)); )
+ {
+ if (e->src == forwarder
+ || !(e->flags & EDGE_FALLTHRU))
+ ei_next (&ei);
+ else
+ redirect_edge_and_branch_force (e, forwarder);
+ }
+
+ /* Fix up the chain of blocks -- make FORWARDER immediately precede the
+ exit block. */
+ FOR_EACH_BB_FN (bb, cfun)
+ {
+ if (bb->aux == NULL && bb != forwarder)
+ {
+ bb->aux = forwarder;
+ break;
+ }
+ }
+}
+
+/* Return true in case it is possible to duplicate the basic block BB. */
+
+static bool
+cfg_layout_can_duplicate_bb_p (const_basic_block bb)
+{
+ /* Do not attempt to duplicate tablejumps, as we need to unshare
+ the dispatch table. This is difficult to do, as the instructions
+ computing jump destination may be hoisted outside the basic block. */
+ if (tablejump_p (BB_END (bb), NULL, NULL))
+ return false;
+
+ /* Do not duplicate blocks containing insns that can't be copied. */
+ if (targetm.cannot_copy_insn_p)
+ {
+ rtx insn = BB_HEAD (bb);
+ while (1)
+ {
+ if (INSN_P (insn) && targetm.cannot_copy_insn_p (insn))
+ return false;
+ if (insn == BB_END (bb))
+ break;
+ insn = NEXT_INSN (insn);
+ }
+ }
+
+ return true;
+}
+
+rtx
+duplicate_insn_chain (rtx from, rtx to)
+{
+ rtx insn, next, last, copy;
+
+ /* Avoid updating of boundaries of previous basic block. The
+ note will get removed from insn stream in fixup. */
+ last = emit_note (NOTE_INSN_DELETED);
+
+ /* Create copy at the end of INSN chain. The chain will
+ be reordered later. */
+ for (insn = from; insn != NEXT_INSN (to); insn = NEXT_INSN (insn))
+ {
+ switch (GET_CODE (insn))
+ {
+ case DEBUG_INSN:
+ /* Don't duplicate label debug insns. */
+ if (TREE_CODE (INSN_VAR_LOCATION_DECL (insn)) == LABEL_DECL)
+ break;
+ /* FALLTHRU */
+ case INSN:
+ case CALL_INSN:
+ case JUMP_INSN:
+ copy = emit_copy_of_insn_after (insn, get_last_insn ());
+ if (JUMP_P (insn) && JUMP_LABEL (insn) != NULL_RTX
+ && ANY_RETURN_P (JUMP_LABEL (insn)))
+ JUMP_LABEL (copy) = JUMP_LABEL (insn);
+ maybe_copy_prologue_epilogue_insn (insn, copy);
+ break;
+
+ case JUMP_TABLE_DATA:
+ /* Avoid copying of dispatch tables. We never duplicate
+ tablejumps, so this can hit only in case the table got
+ moved far from original jump.
+ Avoid copying following barrier as well if any
+ (and debug insns in between). */
+ for (next = NEXT_INSN (insn);
+ next != NEXT_INSN (to);
+ next = NEXT_INSN (next))
+ if (!DEBUG_INSN_P (next))
+ break;
+ if (next != NEXT_INSN (to) && BARRIER_P (next))
+ insn = next;
+ break;
+
+ case CODE_LABEL:
+ break;
+
+ case BARRIER:
+ emit_barrier ();
+ break;
+
+ case NOTE:
+ switch (NOTE_KIND (insn))
+ {
+ /* In case prologue is empty and function contain label
+ in first BB, we may want to copy the block. */
+ case NOTE_INSN_PROLOGUE_END:
+
+ case NOTE_INSN_DELETED:
+ case NOTE_INSN_DELETED_LABEL:
+ case NOTE_INSN_DELETED_DEBUG_LABEL:
+ /* No problem to strip these. */
+ case NOTE_INSN_FUNCTION_BEG:
+ /* There is always just single entry to function. */
+ case NOTE_INSN_BASIC_BLOCK:
+ /* We should only switch text sections once. */
+ case NOTE_INSN_SWITCH_TEXT_SECTIONS:
+ break;
+
+ case NOTE_INSN_EPILOGUE_BEG:
+ emit_note_copy (insn);
+ break;
+
+ default:
+ /* All other notes should have already been eliminated. */
+ gcc_unreachable ();
+ }
+ break;
+ default:
+ gcc_unreachable ();
+ }
+ }
+ insn = NEXT_INSN (last);
+ delete_insn (last);
+ return insn;
+}
+
+/* Create a duplicate of the basic block BB. */
+
+static basic_block
+cfg_layout_duplicate_bb (basic_block bb)
+{
+ rtx insn;
+ basic_block new_bb;
+
+ insn = duplicate_insn_chain (BB_HEAD (bb), BB_END (bb));
+ new_bb = create_basic_block (insn,
+ insn ? get_last_insn () : NULL,
+ EXIT_BLOCK_PTR_FOR_FN (cfun)->prev_bb);
+
+ BB_COPY_PARTITION (new_bb, bb);
+ if (BB_HEADER (bb))
+ {
+ insn = BB_HEADER (bb);
+ while (NEXT_INSN (insn))
+ insn = NEXT_INSN (insn);
+ insn = duplicate_insn_chain (BB_HEADER (bb), insn);
+ if (insn)
+ BB_HEADER (new_bb) = unlink_insn_chain (insn, get_last_insn ());
+ }
+
+ if (BB_FOOTER (bb))
+ {
+ insn = BB_FOOTER (bb);
+ while (NEXT_INSN (insn))
+ insn = NEXT_INSN (insn);
+ insn = duplicate_insn_chain (BB_FOOTER (bb), insn);
+ if (insn)
+ BB_FOOTER (new_bb) = unlink_insn_chain (insn, get_last_insn ());
+ }
+
+ return new_bb;
+}
+
+
+/* Main entry point to this module - initialize the datastructures for
+ CFG layout changes. It keeps LOOPS up-to-date if not null.
+
+ FLAGS is a set of additional flags to pass to cleanup_cfg(). */
+
+void
+cfg_layout_initialize (unsigned int flags)
+{
+ rtx x;
+ basic_block bb;
+
+ /* Once bb reordering is complete, cfg layout mode should not be re-entered.
+ Entering cfg layout mode will perform optimizations on the cfg that
+ could affect the bb layout negatively or even require fixups. An
+ example of the latter is if edge forwarding performed when optimizing
+ the cfg layout required moving a block from the hot to the cold section
+ under -freorder-blocks-and-partition. This would create an illegal
+ partitioning unless some manual fixup was performed. */
+ gcc_assert (!crtl->bb_reorder_complete);
+
+ initialize_original_copy_tables ();
+
+ cfg_layout_rtl_register_cfg_hooks ();
+
+ record_effective_endpoints ();
+
+ /* Make sure that the targets of non local gotos are marked. */
+ for (x = nonlocal_goto_handler_labels; x; x = XEXP (x, 1))
+ {
+ bb = BLOCK_FOR_INSN (XEXP (x, 0));
+ bb->flags |= BB_NON_LOCAL_GOTO_TARGET;
+ }
+
+ cleanup_cfg (CLEANUP_CFGLAYOUT | flags);
+}
+
+/* Splits superblocks. */
+void
+break_superblocks (void)
+{
+ sbitmap superblocks;
+ bool need = false;
+ basic_block bb;
+
+ superblocks = sbitmap_alloc (last_basic_block_for_fn (cfun));
+ bitmap_clear (superblocks);
+
+ FOR_EACH_BB_FN (bb, cfun)
+ if (bb->flags & BB_SUPERBLOCK)
+ {
+ bb->flags &= ~BB_SUPERBLOCK;
+ bitmap_set_bit (superblocks, bb->index);
+ need = true;
+ }
+
+ if (need)
+ {
+ rebuild_jump_labels (get_insns ());
+ find_many_sub_basic_blocks (superblocks);
+ }
+
+ free (superblocks);
+}
+
+/* Finalize the changes: reorder insn list according to the sequence specified
+ by aux pointers, enter compensation code, rebuild scope forest. */
+
+void
+cfg_layout_finalize (void)
+{
+#ifdef ENABLE_CHECKING
+ verify_flow_info ();
+#endif
+ force_one_exit_fallthru ();
+ rtl_register_cfg_hooks ();
+ if (reload_completed
+#ifdef HAVE_epilogue
+ && !HAVE_epilogue
+#endif
+ )
+ fixup_fallthru_exit_predecessor ();
+ fixup_reorder_chain ();
+
+ rebuild_jump_labels (get_insns ());
+ delete_dead_jumptables ();
+
+#ifdef ENABLE_CHECKING
+ verify_insn_chain ();
+ verify_flow_info ();
+#endif
+}
+
+
+/* Same as split_block but update cfg_layout structures. */
+
+static basic_block
+cfg_layout_split_block (basic_block bb, void *insnp)
+{
+ rtx insn = (rtx) insnp;
+ basic_block new_bb = rtl_split_block (bb, insn);
+
+ BB_FOOTER (new_bb) = BB_FOOTER (bb);
+ BB_FOOTER (bb) = NULL;
+
+ return new_bb;
+}
+
+/* Redirect Edge to DEST. */
+static edge
+cfg_layout_redirect_edge_and_branch (edge e, basic_block dest)
+{
+ basic_block src = e->src;
+ edge ret;
+
+ if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH))
+ return NULL;
+
+ if (e->dest == dest)
+ return e;
+
+ if (e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun)
+ && (ret = try_redirect_by_replacing_jump (e, dest, true)))
+ {
+ df_set_bb_dirty (src);
+ return ret;
+ }
+
+ if (e->src == ENTRY_BLOCK_PTR_FOR_FN (cfun)
+ && (e->flags & EDGE_FALLTHRU) && !(e->flags & EDGE_COMPLEX))
+ {
+ if (dump_file)
+ fprintf (dump_file, "Redirecting entry edge from bb %i to %i\n",
+ e->src->index, dest->index);
+
+ df_set_bb_dirty (e->src);
+ redirect_edge_succ (e, dest);
+ return e;
+ }
+
+ /* Redirect_edge_and_branch may decide to turn branch into fallthru edge
+ in the case the basic block appears to be in sequence. Avoid this
+ transformation. */
+
+ if (e->flags & EDGE_FALLTHRU)
+ {
+ /* Redirect any branch edges unified with the fallthru one. */
+ if (JUMP_P (BB_END (src))
+ && label_is_jump_target_p (BB_HEAD (e->dest),
+ BB_END (src)))
+ {
+ edge redirected;
+
+ if (dump_file)
+ fprintf (dump_file, "Fallthru edge unified with branch "
+ "%i->%i redirected to %i\n",
+ e->src->index, e->dest->index, dest->index);
+ e->flags &= ~EDGE_FALLTHRU;
+ redirected = redirect_branch_edge (e, dest);
+ gcc_assert (redirected);
+ redirected->flags |= EDGE_FALLTHRU;
+ df_set_bb_dirty (redirected->src);
+ return redirected;
+ }
+ /* In case we are redirecting fallthru edge to the branch edge
+ of conditional jump, remove it. */
+ if (EDGE_COUNT (src->succs) == 2)
+ {
+ /* Find the edge that is different from E. */
+ edge s = EDGE_SUCC (src, EDGE_SUCC (src, 0) == e);
+
+ if (s->dest == dest
+ && any_condjump_p (BB_END (src))
+ && onlyjump_p (BB_END (src)))
+ delete_insn (BB_END (src));
+ }
+ if (dump_file)
+ fprintf (dump_file, "Redirecting fallthru edge %i->%i to %i\n",
+ e->src->index, e->dest->index, dest->index);
+ ret = redirect_edge_succ_nodup (e, dest);
+ }
+ else
+ ret = redirect_branch_edge (e, dest);
+
+ /* We don't want simplejumps in the insn stream during cfglayout. */
+ gcc_assert (!simplejump_p (BB_END (src)));
+
+ df_set_bb_dirty (src);
+ return ret;
+}
+
+/* Simple wrapper as we always can redirect fallthru edges. */
+static basic_block
+cfg_layout_redirect_edge_and_branch_force (edge e, basic_block dest)
+{
+ edge redirected = cfg_layout_redirect_edge_and_branch (e, dest);
+
+ gcc_assert (redirected);
+ return NULL;
+}
+
+/* Same as delete_basic_block but update cfg_layout structures. */
+
+static void
+cfg_layout_delete_block (basic_block bb)
+{
+ rtx insn, next, prev = PREV_INSN (BB_HEAD (bb)), *to, remaints;
+
+ if (BB_HEADER (bb))
+ {
+ next = BB_HEAD (bb);
+ if (prev)
+ NEXT_INSN (prev) = BB_HEADER (bb);
+ else
+ set_first_insn (BB_HEADER (bb));
+ PREV_INSN (BB_HEADER (bb)) = prev;
+ insn = BB_HEADER (bb);
+ while (NEXT_INSN (insn))
+ insn = NEXT_INSN (insn);
+ NEXT_INSN (insn) = next;
+ PREV_INSN (next) = insn;
+ }
+ next = NEXT_INSN (BB_END (bb));
+ if (BB_FOOTER (bb))
+ {
+ insn = BB_FOOTER (bb);
+ while (insn)
+ {
+ if (BARRIER_P (insn))
+ {
+ if (PREV_INSN (insn))
+ NEXT_INSN (PREV_INSN (insn)) = NEXT_INSN (insn);
+ else
+ BB_FOOTER (bb) = NEXT_INSN (insn);
+ if (NEXT_INSN (insn))
+ PREV_INSN (NEXT_INSN (insn)) = PREV_INSN (insn);
+ }
+ if (LABEL_P (insn))
+ break;
+ insn = NEXT_INSN (insn);
+ }
+ if (BB_FOOTER (bb))
+ {
+ insn = BB_END (bb);
+ NEXT_INSN (insn) = BB_FOOTER (bb);
+ PREV_INSN (BB_FOOTER (bb)) = insn;
+ while (NEXT_INSN (insn))
+ insn = NEXT_INSN (insn);
+ NEXT_INSN (insn) = next;
+ if (next)
+ PREV_INSN (next) = insn;
+ else
+ set_last_insn (insn);
+ }
+ }
+ if (bb->next_bb != EXIT_BLOCK_PTR_FOR_FN (cfun))
+ to = &BB_HEADER (bb->next_bb);
+ else
+ to = &cfg_layout_function_footer;
+
+ rtl_delete_block (bb);
+
+ if (prev)
+ prev = NEXT_INSN (prev);
+ else
+ prev = get_insns ();
+ if (next)
+ next = PREV_INSN (next);
+ else
+ next = get_last_insn ();
+
+ if (next && NEXT_INSN (next) != prev)
+ {
+ remaints = unlink_insn_chain (prev, next);
+ insn = remaints;
+ while (NEXT_INSN (insn))
+ insn = NEXT_INSN (insn);
+ NEXT_INSN (insn) = *to;
+ if (*to)
+ PREV_INSN (*to) = insn;
+ *to = remaints;
+ }
+}
+
+/* Return true when blocks A and B can be safely merged. */
+
+static bool
+cfg_layout_can_merge_blocks_p (basic_block a, basic_block b)
+{
+ /* If we are partitioning hot/cold basic blocks, we don't want to
+ mess up unconditional or indirect jumps that cross between hot
+ and cold sections.
+
+ Basic block partitioning may result in some jumps that appear to
+ be optimizable (or blocks that appear to be mergeable), but which really
+ must be left untouched (they are required to make it safely across
+ partition boundaries). See the comments at the top of
+ bb-reorder.c:partition_hot_cold_basic_blocks for complete details. */
+
+ if (BB_PARTITION (a) != BB_PARTITION (b))
+ return false;
+
+ /* Protect the loop latches. */
+ if (current_loops && b->loop_father->latch == b)
+ return false;
+
+ /* If we would end up moving B's instructions, make sure it doesn't fall
+ through into the exit block, since we cannot recover from a fallthrough
+ edge into the exit block occurring in the middle of a function. */
+ if (NEXT_INSN (BB_END (a)) != BB_HEAD (b))
+ {
+ edge e = find_fallthru_edge (b->succs);
+ if (e && e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun))
+ return false;
+ }
+
+ /* There must be exactly one edge in between the blocks. */
+ return (single_succ_p (a)
+ && single_succ (a) == b
+ && single_pred_p (b) == 1
+ && a != b
+ /* Must be simple edge. */
+ && !(single_succ_edge (a)->flags & EDGE_COMPLEX)
+ && a != ENTRY_BLOCK_PTR_FOR_FN (cfun)
+ && b != EXIT_BLOCK_PTR_FOR_FN (cfun)
+ /* If the jump insn has side effects, we can't kill the edge.
+ When not optimizing, try_redirect_by_replacing_jump will
+ not allow us to redirect an edge by replacing a table jump. */
+ && (!JUMP_P (BB_END (a))
+ || ((!optimize || reload_completed)
+ ? simplejump_p (BB_END (a)) : onlyjump_p (BB_END (a)))));
+}
+
+/* Merge block A and B. The blocks must be mergeable. */
+
+static void
+cfg_layout_merge_blocks (basic_block a, basic_block b)
+{
+ bool forwarder_p = (b->flags & BB_FORWARDER_BLOCK) != 0;
+ rtx insn;
+
+ gcc_checking_assert (cfg_layout_can_merge_blocks_p (a, b));
+
+ if (dump_file)
+ fprintf (dump_file, "Merging block %d into block %d...\n", b->index,
+ a->index);
+
+ /* If there was a CODE_LABEL beginning B, delete it. */
+ if (LABEL_P (BB_HEAD (b)))
+ {
+ delete_insn (BB_HEAD (b));
+ }
+
+ /* We should have fallthru edge in a, or we can do dummy redirection to get
+ it cleaned up. */
+ if (JUMP_P (BB_END (a)))
+ try_redirect_by_replacing_jump (EDGE_SUCC (a, 0), b, true);
+ gcc_assert (!JUMP_P (BB_END (a)));
+
+ /* When not optimizing CFG and the edge is the only place in RTL which holds
+ some unique locus, emit a nop with that locus in between. */
+ if (!optimize)
+ emit_nop_for_unique_locus_between (a, b);
+
+ /* Move things from b->footer after a->footer. */
+ if (BB_FOOTER (b))
+ {
+ if (!BB_FOOTER (a))
+ BB_FOOTER (a) = BB_FOOTER (b);
+ else
+ {
+ rtx last = BB_FOOTER (a);
+
+ while (NEXT_INSN (last))
+ last = NEXT_INSN (last);
+ NEXT_INSN (last) = BB_FOOTER (b);
+ PREV_INSN (BB_FOOTER (b)) = last;
+ }
+ BB_FOOTER (b) = NULL;
+ }
+
+ /* Move things from b->header before a->footer.
+ Note that this may include dead tablejump data, but we don't clean
+ those up until we go out of cfglayout mode. */
+ if (BB_HEADER (b))
+ {
+ if (! BB_FOOTER (a))
+ BB_FOOTER (a) = BB_HEADER (b);
+ else
+ {
+ rtx last = BB_HEADER (b);
+
+ while (NEXT_INSN (last))
+ last = NEXT_INSN (last);
+ NEXT_INSN (last) = BB_FOOTER (a);
+ PREV_INSN (BB_FOOTER (a)) = last;
+ BB_FOOTER (a) = BB_HEADER (b);
+ }
+ BB_HEADER (b) = NULL;
+ }
+
+ /* In the case basic blocks are not adjacent, move them around. */
+ if (NEXT_INSN (BB_END (a)) != BB_HEAD (b))
+ {
+ insn = unlink_insn_chain (BB_HEAD (b), BB_END (b));
+
+ emit_insn_after_noloc (insn, BB_END (a), a);
+ }
+ /* Otherwise just re-associate the instructions. */
+ else
+ {
+ insn = BB_HEAD (b);
+ BB_END (a) = BB_END (b);
+ }
+
+ /* emit_insn_after_noloc doesn't call df_insn_change_bb.
+ We need to explicitly call. */
+ update_bb_for_insn_chain (insn, BB_END (b), a);
+
+ /* Skip possible DELETED_LABEL insn. */
+ if (!NOTE_INSN_BASIC_BLOCK_P (insn))
+ insn = NEXT_INSN (insn);
+ gcc_assert (NOTE_INSN_BASIC_BLOCK_P (insn));
+ BB_HEAD (b) = BB_END (b) = NULL;
+ delete_insn (insn);
+
+ df_bb_delete (b->index);
+
+ /* If B was a forwarder block, propagate the locus on the edge. */
+ if (forwarder_p
+ && LOCATION_LOCUS (EDGE_SUCC (b, 0)->goto_locus) == UNKNOWN_LOCATION)
+ EDGE_SUCC (b, 0)->goto_locus = EDGE_SUCC (a, 0)->goto_locus;
+
+ if (dump_file)
+ fprintf (dump_file, "Merged blocks %d and %d.\n", a->index, b->index);
+}
+
+/* Split edge E. */
+
+static basic_block
+cfg_layout_split_edge (edge e)
+{
+ basic_block new_bb =
+ create_basic_block (e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun)
+ ? NEXT_INSN (BB_END (e->src)) : get_insns (),
+ NULL_RTX, e->src);
+
+ if (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun))
+ BB_COPY_PARTITION (new_bb, e->src);
+ else
+ BB_COPY_PARTITION (new_bb, e->dest);
+ make_edge (new_bb, e->dest, EDGE_FALLTHRU);
+ redirect_edge_and_branch_force (e, new_bb);
+
+ return new_bb;
+}
+
+/* Do postprocessing after making a forwarder block joined by edge FALLTHRU. */
+
+static void
+rtl_make_forwarder_block (edge fallthru ATTRIBUTE_UNUSED)
+{
+}
+
+/* Return true if BB contains only labels or non-executable
+ instructions. */
+
+static bool
+rtl_block_empty_p (basic_block bb)
+{
+ rtx insn;
+
+ if (bb == ENTRY_BLOCK_PTR_FOR_FN (cfun)
+ || bb == EXIT_BLOCK_PTR_FOR_FN (cfun))
+ return true;
+
+ FOR_BB_INSNS (bb, insn)
+ if (NONDEBUG_INSN_P (insn) && !any_uncondjump_p (insn))
+ return false;
+
+ return true;
+}
+
+/* Split a basic block if it ends with a conditional branch and if
+ the other part of the block is not empty. */
+
+static basic_block
+rtl_split_block_before_cond_jump (basic_block bb)
+{
+ rtx insn;
+ rtx split_point = NULL;
+ rtx last = NULL;
+ bool found_code = false;
+
+ FOR_BB_INSNS (bb, insn)
+ {
+ if (any_condjump_p (insn))
+ split_point = last;
+ else if (NONDEBUG_INSN_P (insn))
+ found_code = true;
+ last = insn;
+ }
+
+ /* Did not find everything. */
+ if (found_code && split_point)
+ return split_block (bb, split_point)->dest;
+ else
+ return NULL;
+}
+
+/* Return 1 if BB ends with a call, possibly followed by some
+ instructions that must stay with the call, 0 otherwise. */
+
+static bool
+rtl_block_ends_with_call_p (basic_block bb)
+{
+ rtx insn = BB_END (bb);
+
+ while (!CALL_P (insn)
+ && insn != BB_HEAD (bb)
+ && (keep_with_call_p (insn)
+ || NOTE_P (insn)
+ || DEBUG_INSN_P (insn)))
+ insn = PREV_INSN (insn);
+ return (CALL_P (insn));
+}
+
+/* Return 1 if BB ends with a conditional branch, 0 otherwise. */
+
+static bool
+rtl_block_ends_with_condjump_p (const_basic_block bb)
+{
+ return any_condjump_p (BB_END (bb));
+}
+
+/* Return true if we need to add fake edge to exit.
+ Helper function for rtl_flow_call_edges_add. */
+
+static bool
+need_fake_edge_p (const_rtx insn)
+{
+ if (!INSN_P (insn))
+ return false;
+
+ if ((CALL_P (insn)
+ && !SIBLING_CALL_P (insn)
+ && !find_reg_note (insn, REG_NORETURN, NULL)
+ && !(RTL_CONST_OR_PURE_CALL_P (insn))))
+ return true;
+
+ return ((GET_CODE (PATTERN (insn)) == ASM_OPERANDS
+ && MEM_VOLATILE_P (PATTERN (insn)))
+ || (GET_CODE (PATTERN (insn)) == PARALLEL
+ && asm_noperands (insn) != -1
+ && MEM_VOLATILE_P (XVECEXP (PATTERN (insn), 0, 0)))
+ || GET_CODE (PATTERN (insn)) == ASM_INPUT);
+}
+
+/* Add fake edges to the function exit for any non constant and non noreturn
+ calls, volatile inline assembly in the bitmap of blocks specified by
+ BLOCKS or to the whole CFG if BLOCKS is zero. Return the number of blocks
+ that were split.
+
+ The goal is to expose cases in which entering a basic block does not imply
+ that all subsequent instructions must be executed. */
+
+static int
+rtl_flow_call_edges_add (sbitmap blocks)
+{
+ int i;
+ int blocks_split = 0;
+ int last_bb = last_basic_block_for_fn (cfun);
+ bool check_last_block = false;
+
+ if (n_basic_blocks_for_fn (cfun) == NUM_FIXED_BLOCKS)
+ return 0;
+
+ if (! blocks)
+ check_last_block = true;
+ else
+ check_last_block = bitmap_bit_p (blocks,
+ EXIT_BLOCK_PTR_FOR_FN (cfun)->prev_bb->index);
+
+ /* In the last basic block, before epilogue generation, there will be
+ a fallthru edge to EXIT. Special care is required if the last insn
+ of the last basic block is a call because make_edge folds duplicate
+ edges, which would result in the fallthru edge also being marked
+ fake, which would result in the fallthru edge being removed by
+ remove_fake_edges, which would result in an invalid CFG.
+
+ Moreover, we can't elide the outgoing fake edge, since the block
+ profiler needs to take this into account in order to solve the minimal
+ spanning tree in the case that the call doesn't return.
+
+ Handle this by adding a dummy instruction in a new last basic block. */
+ if (check_last_block)
+ {
+ basic_block bb = EXIT_BLOCK_PTR_FOR_FN (cfun)->prev_bb;
+ rtx insn = BB_END (bb);
+
+ /* Back up past insns that must be kept in the same block as a call. */
+ while (insn != BB_HEAD (bb)
+ && keep_with_call_p (insn))
+ insn = PREV_INSN (insn);
+
+ if (need_fake_edge_p (insn))
+ {
+ edge e;
+
+ e = find_edge (bb, EXIT_BLOCK_PTR_FOR_FN (cfun));
+ if (e)
+ {
+ insert_insn_on_edge (gen_use (const0_rtx), e);
+ commit_edge_insertions ();
+ }
+ }
+ }
+
+ /* Now add fake edges to the function exit for any non constant
+ calls since there is no way that we can determine if they will
+ return or not... */
+
+ for (i = NUM_FIXED_BLOCKS; i < last_bb; i++)
+ {
+ basic_block bb = BASIC_BLOCK_FOR_FN (cfun, i);
+ rtx insn;
+ rtx prev_insn;
+
+ if (!bb)
+ continue;
+
+ if (blocks && !bitmap_bit_p (blocks, i))
+ continue;
+
+ for (insn = BB_END (bb); ; insn = prev_insn)
+ {
+ prev_insn = PREV_INSN (insn);
+ if (need_fake_edge_p (insn))
+ {
+ edge e;
+ rtx split_at_insn = insn;
+
+ /* Don't split the block between a call and an insn that should
+ remain in the same block as the call. */
+ if (CALL_P (insn))
+ while (split_at_insn != BB_END (bb)
+ && keep_with_call_p (NEXT_INSN (split_at_insn)))
+ split_at_insn = NEXT_INSN (split_at_insn);
+
+ /* The handling above of the final block before the epilogue
+ should be enough to verify that there is no edge to the exit
+ block in CFG already. Calling make_edge in such case would
+ cause us to mark that edge as fake and remove it later. */
+
+#ifdef ENABLE_CHECKING
+ if (split_at_insn == BB_END (bb))
+ {
+ e = find_edge (bb, EXIT_BLOCK_PTR_FOR_FN (cfun));
+ gcc_assert (e == NULL);
+ }
+#endif
+
+ /* Note that the following may create a new basic block
+ and renumber the existing basic blocks. */
+ if (split_at_insn != BB_END (bb))
+ {
+ e = split_block (bb, split_at_insn);
+ if (e)
+ blocks_split++;
+ }
+
+ make_edge (bb, EXIT_BLOCK_PTR_FOR_FN (cfun), EDGE_FAKE);
+ }
+
+ if (insn == BB_HEAD (bb))
+ break;
+ }
+ }
+
+ if (blocks_split)
+ verify_flow_info ();
+
+ return blocks_split;
+}
+
+/* Add COMP_RTX as a condition at end of COND_BB. FIRST_HEAD is
+ the conditional branch target, SECOND_HEAD should be the fall-thru
+ there is no need to handle this here the loop versioning code handles
+ this. the reason for SECON_HEAD is that it is needed for condition
+ in trees, and this should be of the same type since it is a hook. */
+static void
+rtl_lv_add_condition_to_bb (basic_block first_head ,
+ basic_block second_head ATTRIBUTE_UNUSED,
+ basic_block cond_bb, void *comp_rtx)
+{
+ rtx label, seq, jump;
+ rtx op0 = XEXP ((rtx)comp_rtx, 0);
+ rtx op1 = XEXP ((rtx)comp_rtx, 1);
+ enum rtx_code comp = GET_CODE ((rtx)comp_rtx);
+ enum machine_mode mode;
+
+
+ label = block_label (first_head);
+ mode = GET_MODE (op0);
+ if (mode == VOIDmode)
+ mode = GET_MODE (op1);
+
+ start_sequence ();
+ op0 = force_operand (op0, NULL_RTX);
+ op1 = force_operand (op1, NULL_RTX);
+ do_compare_rtx_and_jump (op0, op1, comp, 0,
+ mode, NULL_RTX, NULL_RTX, label, -1);
+ jump = get_last_insn ();
+ JUMP_LABEL (jump) = label;
+ LABEL_NUSES (label)++;
+ seq = get_insns ();
+ end_sequence ();
+
+ /* Add the new cond , in the new head. */
+ emit_insn_after (seq, BB_END (cond_bb));
+}
+
+
+/* Given a block B with unconditional branch at its end, get the
+ store the return the branch edge and the fall-thru edge in
+ BRANCH_EDGE and FALLTHRU_EDGE respectively. */
+static void
+rtl_extract_cond_bb_edges (basic_block b, edge *branch_edge,
+ edge *fallthru_edge)
+{
+ edge e = EDGE_SUCC (b, 0);
+
+ if (e->flags & EDGE_FALLTHRU)
+ {
+ *fallthru_edge = e;
+ *branch_edge = EDGE_SUCC (b, 1);
+ }
+ else
+ {
+ *branch_edge = e;
+ *fallthru_edge = EDGE_SUCC (b, 1);
+ }
+}
+
+void
+init_rtl_bb_info (basic_block bb)
+{
+ gcc_assert (!bb->il.x.rtl);
+ bb->il.x.head_ = NULL;
+ bb->il.x.rtl = ggc_alloc_cleared_rtl_bb_info ();
+}
+
+/* Returns true if it is possible to remove edge E by redirecting
+ it to the destination of the other edge from E->src. */
+
+static bool
+rtl_can_remove_branch_p (const_edge e)
+{
+ const_basic_block src = e->src;
+ const_basic_block target = EDGE_SUCC (src, EDGE_SUCC (src, 0) == e)->dest;
+ const_rtx insn = BB_END (src), set;
+
+ /* The conditions are taken from try_redirect_by_replacing_jump. */
+ if (target == EXIT_BLOCK_PTR_FOR_FN (cfun))
+ return false;
+
+ if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH))
+ return false;
+
+ if (BB_PARTITION (src) != BB_PARTITION (target))
+ return false;
+
+ if (!onlyjump_p (insn)
+ || tablejump_p (insn, NULL, NULL))
+ return false;
+
+ set = single_set (insn);
+ if (!set || side_effects_p (set))
+ return false;
+
+ return true;
+}
+
+static basic_block
+rtl_duplicate_bb (basic_block bb)
+{
+ bb = cfg_layout_duplicate_bb (bb);
+ bb->aux = NULL;
+ return bb;
+}
+
+/* Do book-keeping of basic block BB for the profile consistency checker.
+ If AFTER_PASS is 0, do pre-pass accounting, or if AFTER_PASS is 1
+ then do post-pass accounting. Store the counting in RECORD. */
+static void
+rtl_account_profile_record (basic_block bb, int after_pass,
+ struct profile_record *record)
+{
+ rtx insn;
+ FOR_BB_INSNS (bb, insn)
+ if (INSN_P (insn))
+ {
+ record->size[after_pass]
+ += insn_rtx_cost (PATTERN (insn), false);
+ if (profile_status_for_fn (cfun) == PROFILE_READ)
+ record->time[after_pass]
+ += insn_rtx_cost (PATTERN (insn), true) * bb->count;
+ else if (profile_status_for_fn (cfun) == PROFILE_GUESSED)
+ record->time[after_pass]
+ += insn_rtx_cost (PATTERN (insn), true) * bb->frequency;
+ }
+}
+
+/* Implementation of CFG manipulation for linearized RTL. */
+struct cfg_hooks rtl_cfg_hooks = {
+ "rtl",
+ rtl_verify_flow_info,
+ rtl_dump_bb,
+ rtl_dump_bb_for_graph,
+ rtl_create_basic_block,
+ rtl_redirect_edge_and_branch,
+ rtl_redirect_edge_and_branch_force,
+ rtl_can_remove_branch_p,
+ rtl_delete_block,
+ rtl_split_block,
+ rtl_move_block_after,
+ rtl_can_merge_blocks, /* can_merge_blocks_p */
+ rtl_merge_blocks,
+ rtl_predict_edge,
+ rtl_predicted_by_p,
+ cfg_layout_can_duplicate_bb_p,
+ rtl_duplicate_bb,
+ rtl_split_edge,
+ rtl_make_forwarder_block,
+ rtl_tidy_fallthru_edge,
+ rtl_force_nonfallthru,
+ rtl_block_ends_with_call_p,
+ rtl_block_ends_with_condjump_p,
+ rtl_flow_call_edges_add,
+ NULL, /* execute_on_growing_pred */
+ NULL, /* execute_on_shrinking_pred */
+ NULL, /* duplicate loop for trees */
+ NULL, /* lv_add_condition_to_bb */
+ NULL, /* lv_adjust_loop_header_phi*/
+ NULL, /* extract_cond_bb_edges */
+ NULL, /* flush_pending_stmts */
+ rtl_block_empty_p, /* block_empty_p */
+ rtl_split_block_before_cond_jump, /* split_block_before_cond_jump */
+ rtl_account_profile_record,
+};
+
+/* Implementation of CFG manipulation for cfg layout RTL, where
+ basic block connected via fallthru edges does not have to be adjacent.
+ This representation will hopefully become the default one in future
+ version of the compiler. */
+
+struct cfg_hooks cfg_layout_rtl_cfg_hooks = {
+ "cfglayout mode",
+ rtl_verify_flow_info_1,
+ rtl_dump_bb,
+ rtl_dump_bb_for_graph,
+ cfg_layout_create_basic_block,
+ cfg_layout_redirect_edge_and_branch,
+ cfg_layout_redirect_edge_and_branch_force,
+ rtl_can_remove_branch_p,
+ cfg_layout_delete_block,
+ cfg_layout_split_block,
+ rtl_move_block_after,
+ cfg_layout_can_merge_blocks_p,
+ cfg_layout_merge_blocks,
+ rtl_predict_edge,
+ rtl_predicted_by_p,
+ cfg_layout_can_duplicate_bb_p,
+ cfg_layout_duplicate_bb,
+ cfg_layout_split_edge,
+ rtl_make_forwarder_block,
+ NULL, /* tidy_fallthru_edge */
+ rtl_force_nonfallthru,
+ rtl_block_ends_with_call_p,
+ rtl_block_ends_with_condjump_p,
+ rtl_flow_call_edges_add,
+ NULL, /* execute_on_growing_pred */
+ NULL, /* execute_on_shrinking_pred */
+ duplicate_loop_to_header_edge, /* duplicate loop for trees */
+ rtl_lv_add_condition_to_bb, /* lv_add_condition_to_bb */
+ NULL, /* lv_adjust_loop_header_phi*/
+ rtl_extract_cond_bb_edges, /* extract_cond_bb_edges */
+ NULL, /* flush_pending_stmts */
+ rtl_block_empty_p, /* block_empty_p */
+ rtl_split_block_before_cond_jump, /* split_block_before_cond_jump */
+ rtl_account_profile_record,
+};
+
+#include "gt-cfgrtl.h"