/* Control flow graph manipulation code for GNU compiler.
Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
- 1999, 2000, 2001, 2002 Free Software Foundation, Inc.
+ 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
+ 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 2, or (at your option) any later
+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
for more details.
You should have received a copy of the GNU General Public License
-along with GCC; see the file COPYING. If not, write to the Free
-Software Foundation, 59 Temple Place - Suite 330, Boston, MA
-02111-1307, USA. */
+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
- - Basic block manipulation
- create_basic_block, flow_delete_block, split_block,
- merge_blocks_nomove
+ - 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, redirect_edge_and_branch,
- redirect_edge_and_branch_force, tidy_fallthru_edge, force_nonfallthru
- - Edge splitting and committing to edges
- split_edge, insert_insn_on_edge, commit_edge_insertions
- - Dumping and debugging
- print_rtl_with_bb, dump_bb, debug_bb, debug_bb_n
- - Consistency checking
- verify_flow_info
- - CFG updating after constant propagation
- purge_dead_edges, purge_all_dead_edges */
+ block_label, tidy_fallthru_edge, force_nonfallthru */
\f
#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "tm.h"
#include "tree.h"
-#include "rtl.h"
#include "hard-reg-set.h"
#include "basic-block.h"
#include "regs.h"
#include "output.h"
#include "function.h"
#include "except.h"
-#include "toplev.h"
+#include "rtl-error.h"
#include "tm_p.h"
#include "obstack.h"
+#include "insn-attr.h"
#include "insn-config.h"
-
-/* Stubs in case we don't have a return insn. */
-#ifndef HAVE_return
-#define HAVE_return 0
-#define gen_return() NULL_RTX
-#endif
-
-/* The labels mentioned in non-jump rtl. Valid during find_basic_blocks. */
-/* ??? Should probably be using LABEL_NUSES instead. It would take a
- bit of surgery to be able to use or co-opt the routines in jump. */
-rtx label_value_list;
-rtx tail_recursion_label_list;
-
-static int can_delete_note_p PARAMS ((rtx));
-static int can_delete_label_p PARAMS ((rtx));
-static void commit_one_edge_insertion PARAMS ((edge, int));
-static bool try_redirect_by_replacing_jump PARAMS ((edge, basic_block));
-static rtx last_loop_beg_note PARAMS ((rtx));
-static bool back_edge_of_syntactic_loop_p PARAMS ((basic_block, basic_block));
-basic_block force_nonfallthru_and_redirect PARAMS ((edge, basic_block));
+#include "cfglayout.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"
+
+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 (basic_block, FILE *, int, int);
+static int rtl_verify_flow_info_1 (void);
+static void rtl_make_forwarder_block (edge);
\f
/* 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 (note)
- rtx note;
+can_delete_note_p (const_rtx note)
{
- return (NOTE_LINE_NUMBER (note) == NOTE_INSN_DELETED
- || NOTE_LINE_NUMBER (note) == NOTE_INSN_BASIC_BLOCK
- || NOTE_LINE_NUMBER (note) == NOTE_INSN_PREDICTION);
+ 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 (label)
- rtx label;
+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)
- && !in_expr_list_p (label_value_list, label));
+ && !in_expr_list_p (forced_labels, label));
}
/* Delete INSN by patching it out. Return the next insn. */
rtx
-delete_insn (insn)
- rtx insn;
+delete_insn (rtx insn)
{
rtx next = NEXT_INSN (insn);
rtx note;
bool really_delete = true;
- if (GET_CODE (insn) == CODE_LABEL)
+ 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. */
+ 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);
really_delete = false;
PUT_CODE (insn, NOTE);
- NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED_LABEL;
- NOTE_SOURCE_FILE (insn) = name;
+ NOTE_KIND (insn) = NOTE_INSN_DELETED_LABEL;
+ NOTE_DELETED_LABEL_NAME (insn) = name;
}
remove_node_from_expr_list (insn, &nonlocal_goto_handler_labels);
if (really_delete)
{
/* If this insn has already been deleted, something is very wrong. */
- if (INSN_DELETED_P (insn))
- abort ();
+ gcc_assert (!INSN_DELETED_P (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 (GET_CODE (insn) == JUMP_INSN
- && JUMP_LABEL (insn)
- && GET_CODE (JUMP_LABEL (insn)) == CODE_LABEL)
- LABEL_NUSES (JUMP_LABEL (insn))--;
+ 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 an insn that references a label. */
- else if ((note = find_reg_note (insn, REG_LABEL, NULL_RTX)) != NULL_RTX
- && GET_CODE (XEXP (note, 0)) == CODE_LABEL)
- LABEL_NUSES (XEXP (note, 0))--;
+ /* 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 (GET_CODE (insn) == JUMP_INSN
- && (GET_CODE (PATTERN (insn)) == ADDR_VEC
- || GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC))
+ if (JUMP_TABLE_DATA_P (insn))
{
rtx pat = PATTERN (insn);
int diff_vec_p = GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC;
/* 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 (GET_CODE (label) != NOTE)
+ if (!NOTE_P (label))
LABEL_NUSES (label)--;
}
}
}
/* Like delete_insn but also purge dead edges from BB. */
+
rtx
-delete_insn_and_edges (insn)
- rtx insn;
+delete_insn_and_edges (rtx insn)
{
rtx x;
bool purge = false;
if (INSN_P (insn)
&& BLOCK_FOR_INSN (insn)
- && BLOCK_FOR_INSN (insn)->end == insn)
+ && BB_END (BLOCK_FOR_INSN (insn)) == insn)
purge = true;
x = delete_insn (insn);
if (purge)
}
/* Unlink a chain of insns between START and FINISH, leaving notes
- that must be paired. */
+ 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 (start, finish)
- rtx start, finish;
+delete_insn_chain (rtx start, rtx finish, bool clear_bb)
{
rtx next;
while (1)
{
next = NEXT_INSN (start);
- if (GET_CODE (start) == NOTE && !can_delete_note_p (start))
+ if (NOTE_P (start) && !can_delete_note_p (start))
;
else
next = delete_insn (start);
+ if (clear_bb && !INSN_DELETED_P (start))
+ set_block_for_insn (start, NULL);
+
if (start == finish)
break;
start = next;
}
}
-
-/* Like delete_insn but also purge dead edges from BB. */
-void
-delete_insn_chain_and_edges (first, last)
- rtx first, last;
-{
- bool purge = false;
-
- if (INSN_P (last)
- && BLOCK_FOR_INSN (last)
- && BLOCK_FOR_INSN (last)->end == last)
- purge = true;
- delete_insn_chain (first, last);
- if (purge)
- purge_dead_edges (BLOCK_FOR_INSN (last));
-}
\f
/* Create a new basic block consisting of the instructions between HEAD and END
inclusive. This function is designed to allow fast BB construction - reuses
AFTER is the basic block we should be put after. */
basic_block
-create_basic_block_structure (head, end, bb_note, after)
- rtx head, end, bb_note;
- basic_block after;
+create_basic_block_structure (rtx head, rtx end, rtx bb_note, basic_block after)
{
basic_block bb;
if (bb_note
- && ! RTX_INTEGRATED_P (bb_note)
&& (bb = NOTE_BASIC_BLOCK (bb_note)) != NULL
&& bb->aux == NULL)
{
rtx after;
- if (GET_CODE (head) == CODE_LABEL)
+ if (LABEL_P (head))
after = head;
else
{
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 (GET_CODE (head) == CODE_LABEL && end)
+ else if (LABEL_P (head) && end)
{
bb_note = emit_note_after (NOTE_INSN_BASIC_BLOCK, head);
if (head == end)
if (NEXT_INSN (end) == bb_note)
end = bb_note;
- bb->head = head;
- bb->end = end;
+ BB_HEAD (bb) = head;
+ BB_END (bb) = end;
bb->index = last_basic_block++;
- bb->flags = BB_NEW;
+ bb->flags = BB_NEW | BB_RTL;
link_block (bb, after);
- BASIC_BLOCK (bb->index) = bb;
+ SET_BASIC_BLOCK (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. */
create new empty basic block before HEAD. Both END and HEAD can be NULL to
create basic block at the end of INSN chain. */
-basic_block
-create_basic_block (head, end, after)
- rtx head, end;
- basic_block after;
+static basic_block
+rtl_create_basic_block (void *headp, void *endp, basic_block after)
{
+ rtx head = (rtx) headp, end = (rtx) endp;
basic_block bb;
- /* Place the new block just after the end. */
- VARRAY_GROW (basic_block_info, last_basic_block+1);
+ /* Grow the basic block array if needed. */
+ if ((size_t) last_basic_block >= VEC_length (basic_block, basic_block_info))
+ {
+ size_t new_size = last_basic_block + (last_basic_block + 3) / 4;
+ VEC_safe_grow_cleared (basic_block, gc, basic_block_info, new_size);
+ }
n_basic_blocks++;
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;
+}
\f
/* Delete the insns in a (non-live) block. We physically delete every
non-deleted-note insn, and update the flow graph appropriately.
/* ??? Preserving all such notes strikes me as wrong. It would be nice
to post-process the stream to remove empty blocks, loops, ranges, etc. */
-int
-flow_delete_block_noexpunge (b)
- basic_block b;
+static void
+rtl_delete_block (basic_block b)
{
- int deleted_handler = 0;
- rtx insn, end, tmp;
+ 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
- and remove the associated NOTE_INSN_EH_REGION_BEG and
- NOTE_INSN_EH_REGION_END notes. */
-
- /* Get rid of all NOTE_INSN_PREDICTIONs and NOTE_INSN_LOOP_CONTs
- hanging before the block. */
-
- for (insn = PREV_INSN (b->head); insn; insn = PREV_INSN (insn))
- {
- if (GET_CODE (insn) != NOTE)
- break;
- if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PREDICTION
- || NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_CONT)
- NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
- }
+ 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);
- insn = b->head;
-
- never_reached_warning (insn, b->end);
-
- if (GET_CODE (insn) == CODE_LABEL)
- maybe_remove_eh_handler (insn);
-
- /* Include any jump table following the basic block. */
- end = b->end;
- if (tablejump_p (end, NULL, &tmp))
- end = tmp;
-
- /* Include any barrier that may follow the basic block. */
- tmp = next_nonnote_insn (end);
- if (tmp && GET_CODE (tmp) == BARRIER)
- end = tmp;
+ end = get_last_bb_insn (b);
/* Selectively delete the entire chain. */
- b->head = NULL;
- delete_insn_chain (insn, end);
+ BB_HEAD (b) = NULL;
+ delete_insn_chain (insn, end, true);
- /* Remove the edges into and out of this block. Note that there may
- indeed be edges in, if we are removing an unreachable loop. */
- while (b->pred != NULL)
- remove_edge (b->pred);
- while (b->succ != NULL)
- remove_edge (b->succ);
- b->pred = NULL;
- b->succ = NULL;
-
- return deleted_handler;
-}
-
-int
-flow_delete_block (b)
- basic_block b;
-{
- int deleted_handler = flow_delete_block_noexpunge (b);
-
- /* Remove the basic block from the array. */
- expunge_block (b);
-
- return deleted_handler;
+ if (dump_file)
+ fprintf (dump_file, "deleting block %d\n", b->index);
+ df_bb_delete (b->index);
}
\f
/* Records the basic block struct in BLOCK_FOR_INSN for every insn. */
void
-compute_bb_for_insn ()
+compute_bb_for_insn (void)
{
basic_block bb;
FOR_EACH_BB (bb)
{
- rtx end = bb->end;
+ rtx end = BB_END (bb);
rtx insn;
- for (insn = bb->head; ; insn = NEXT_INSN (insn))
+ for (insn = BB_HEAD (bb); ; insn = NEXT_INSN (insn))
{
BLOCK_FOR_INSN (insn) = bb;
if (insn == end)
/* Release the basic_block_for_insn array. */
-void
-free_bb_for_insn ()
+unsigned int
+free_bb_for_insn (void)
{
rtx insn;
for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
- if (GET_CODE (insn) != BARRIER)
+ 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
+
+ free_bb_for_insn ();
+ return 0;
}
-/* Update insns block within BB. */
+struct rtl_opt_pass pass_free_cfg =
+{
+ {
+ RTL_PASS,
+ "*free_cfg", /* name */
+ NULL, /* gate */
+ rest_of_pass_free_cfg, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ TV_NONE, /* tv_id */
+ 0, /* properties_required */
+ 0, /* properties_provided */
+ PROP_cfg, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ 0, /* todo_flags_finish */
+ }
+};
+
+/* 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 > NUM_FIXED_BLOCKS ?
+ BB_HEAD (ENTRY_BLOCK_PTR->next_bb) : get_insns ());
+}
+/* Emit INSN at the entry point of the function, ensuring that it is only
+ executed once per function. */
void
-update_bb_for_insn (bb)
- basic_block bb;
+emit_insn_at_entry (rtx insn)
+{
+ edge_iterator ei = ei_start (ENTRY_BLOCK_PTR->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;
- for (insn = bb->head; ; insn = NEXT_INSN (insn))
- {
- if (GET_CODE (insn) != BARRIER)
- set_block_for_insn (insn, bb);
- if (insn == bb->end)
- break;
- }
+ 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);
}
+
\f
-/* Split a block BB after insn INSN creating a new fallthru edge.
- Return the new edge. Note that to keep other parts of the compiler happy,
- this function renumbers all the basic blocks so that the new
- one has a number one greater than the block split. */
+/* Return the INSN immediately following the NOTE_INSN_BASIC_BLOCK
+ note associated with the BLOCK. */
-edge
-split_block (bb, insn)
- basic_block bb;
- rtx insn;
+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;
- edge new_edge;
+ rtx insn = (rtx) insnp;
edge e;
+ edge_iterator ei;
- /* There is no point splitting the block after its end. */
- if (bb->end == insn)
- return 0;
+ if (!insn)
+ {
+ insn = first_insn_after_basic_block_note (bb);
- /* Create the new basic block. */
- new_bb = create_basic_block (NEXT_INSN (insn), bb->end, bb);
- new_bb->count = bb->count;
- new_bb->frequency = bb->frequency;
- new_bb->loop_depth = bb->loop_depth;
- bb->end = insn;
+ if (insn)
+ {
+ rtx next = insn;
- /* Redirect the outgoing edges. */
- new_bb->succ = bb->succ;
- bb->succ = NULL;
- for (e = new_bb->succ; e; e = e->succ_next)
- e->src = new_bb;
+ insn = PREV_INSN (insn);
- new_edge = make_single_succ_edge (bb, new_bb, EDGE_FALLTHRU);
-
- if (bb->global_live_at_start)
- {
- new_bb->global_live_at_start = OBSTACK_ALLOC_REG_SET (&flow_obstack);
- new_bb->global_live_at_end = OBSTACK_ALLOC_REG_SET (&flow_obstack);
- COPY_REG_SET (new_bb->global_live_at_end, bb->global_live_at_end);
-
- /* We now have to calculate which registers are live at the end
- of the split basic block and at the start of the new basic
- block. Start with those registers that are known to be live
- at the end of the original basic block and get
- propagate_block to determine which registers are live. */
- COPY_REG_SET (new_bb->global_live_at_start, bb->global_live_at_end);
- propagate_block (new_bb, new_bb->global_live_at_start, NULL, NULL, 0);
- COPY_REG_SET (bb->global_live_at_end,
- new_bb->global_live_at_start);
-#ifdef HAVE_conditional_execution
- /* In the presence of conditional execution we are not able to update
- liveness precisely. */
- if (reload_completed)
- {
- bb->flags |= BB_DIRTY;
- new_bb->flags |= BB_DIRTY;
+ /* 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);
+ }
}
-#endif
+ else
+ insn = get_last_insn ();
}
- return new_edge;
+ /* 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;
}
/* Blocks A and B are to be merged into a single block A. The insns
- are already contiguous, hence `nomove'. */
+ are already contiguous. */
-void
-merge_blocks_nomove (a, b)
- basic_block a, b;
+static void
+rtl_merge_blocks (basic_block a, basic_block b)
{
- rtx b_head = b->head, b_end = b->end, a_end = a->end;
+ 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;
- edge e;
+
+ 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 (GET_CODE (b_head) == CODE_LABEL)
+ 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 there was a jump out of A, delete it. */
- if (GET_CODE (a_end) == JUMP_INSN)
+ if (JUMP_P (a_end))
{
rtx prev;
for (prev = PREV_INSN (a_end); ; prev = PREV_INSN (prev))
- if (GET_CODE (prev) != NOTE
- || NOTE_LINE_NUMBER (prev) == NOTE_INSN_BASIC_BLOCK
- || prev == a->head)
+ if (!NOTE_P (prev)
+ || NOTE_INSN_BASIC_BLOCK_P (prev)
+ || prev == BB_HEAD (a))
break;
del_first = a_end;
prev = prev_nonnote_insn (prev);
if (!prev)
- prev = a->head;
+ prev = BB_HEAD (a);
del_first = tmp;
}
#endif
a_end = PREV_INSN (del_first);
}
- else if (GET_CODE (NEXT_INSN (a_end)) == BARRIER)
+ else if (BARRIER_P (NEXT_INSN (a_end)))
del_first = NEXT_INSN (a_end);
- /* Normally there should only be one successor of A and that is B, but
- partway though the merge of blocks for conditional_execution we'll
- be merging a TEST block with THEN and ELSE successors. Free the
- whole lot of them and hope the caller knows what they're doing. */
- while (a->succ)
- remove_edge (a->succ);
-
- /* Adjust the edges out of B for the new owner. */
- for (e = b->succ; e; e = e->succ_next)
- e->src = a;
- a->succ = b->succ;
- a->flags |= b->flags;
-
- /* B hasn't quite yet ceased to exist. Attempt to prevent mishap. */
- b->pred = b->succ = NULL;
- a->global_live_at_end = b->global_live_at_end;
-
- expunge_block (b);
-
/* Delete everything marked above as well as crap that might be
hanging out between the two blocks. */
- delete_insn_chain (del_first, del_last);
+ BB_HEAD (b) = NULL;
+ delete_insn_chain (del_first, del_last, true);
/* Reassociate the insns of B with A. */
if (!b_empty)
{
- rtx x;
+ update_bb_for_insn_chain (a_end, b_debug_end, a);
+
+ a_end = b_debug_end;
+ }
+ 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);
+ a_end = b_debug_end;
+ }
- for (x = a_end; x != b_end; x = NEXT_INSN (x))
- set_block_for_insn (x, a);
+ df_bb_delete (b->index);
+ BB_END (a) = a_end;
- set_block_for_insn (b_end, a);
+ /* If B was a forwarder block, propagate the locus on the edge. */
+ if (forwarder_p && !EDGE_SUCC (b, 0)->goto_locus)
+ 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);
+}
- a_end = b_end;
- }
- a->end = a_end;
+/* 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;
+
+ /* 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 && b != EXIT_BLOCK_PTR
+ /* 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)))));
}
\f
/* Return the label in the head of basic block BLOCK. Create one if it doesn't
exist. */
rtx
-block_label (block)
- basic_block block;
+block_label (basic_block block)
{
if (block == EXIT_BLOCK_PTR)
return NULL_RTX;
- if (GET_CODE (block->head) != CODE_LABEL)
+ if (!LABEL_P (BB_HEAD (block)))
{
- block->head = emit_label_before (gen_label_rtx (), block->head);
+ BB_HEAD (block) = emit_label_before (gen_label_rtx (), BB_HEAD (block));
}
- return block->head;
+ return BB_HEAD (block);
}
/* Attempt to perform edge redirection by replacing possibly complex jump
apply only if all edges now point to the same block. The parameters and
return values are equivalent to redirect_edge_and_branch. */
-static bool
-try_redirect_by_replacing_jump (e, target)
- edge e;
- basic_block target;
+edge
+try_redirect_by_replacing_jump (edge e, basic_block target, bool in_cfglayout)
{
basic_block src = e->src;
- rtx insn = src->end, kill_from;
- edge tmp;
+ rtx insn = BB_END (src), kill_from;
rtx set;
int fallthru = 0;
- /* Verify that all targets will be TARGET. */
- for (tmp = src->succ; tmp; tmp = tmp->succ_next)
- if (tmp->dest != target && tmp != e)
- break;
+ /* 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.
- if (tmp || !onlyjump_p (insn))
- return false;
- if ((!optimize || flow2_completed) && tablejump_p (insn, NULL, NULL))
- return false;
+ 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 (find_reg_note (insn, REG_CROSSING_JUMP, NULL_RTX)
+ || 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 false;
+ 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)))
+ 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 (can_fallthru (src, target))
+ if (in_cfglayout || can_fallthru (src, target))
{
- if (rtl_dump_file)
- fprintf (rtl_dump_file, "Removing jump %i.\n", INSN_UID (insn));
+ if (dump_file)
+ fprintf (dump_file, "Removing jump %i.\n", INSN_UID (insn));
fallthru = 1;
/* Selectively unlink whole insn chain. */
- delete_insn_chain (kill_from, PREV_INSN (target->head));
+ if (in_cfglayout)
+ {
+ rtx insn = src->il.rtl->footer;
+
+ 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
+ src->il.rtl->footer = 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 false;
- if (rtl_dump_file)
- fprintf (rtl_dump_file, "Redirecting jump %i from %i to %i.\n",
+ 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))
{
- if (target == EXIT_BLOCK_PTR)
- return false;
- abort ();
+ gcc_assert (target == EXIT_BLOCK_PTR);
+ return NULL;
}
}
/* Cannot do anything for target exit block. */
else if (target == EXIT_BLOCK_PTR)
- return false;
+ 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 (gen_jump (target_label), insn);
- JUMP_LABEL (src->end) = target_label;
+ emit_jump_insn_after_noloc (gen_jump (target_label), insn);
+ JUMP_LABEL (BB_END (src)) = target_label;
LABEL_NUSES (target_label)++;
- if (rtl_dump_file)
- fprintf (rtl_dump_file, "Replacing insn %i by jump %i\n",
- INSN_UID (insn), INSN_UID (src->end));
+ 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);
+ 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);
+ 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;
- barrier = next_nonnote_insn (src->end);
- if (!barrier || GET_CODE (barrier) != BARRIER)
- emit_barrier_after (src->end);
+ PREV_INSN (new_insn) = PREV_INSN (barrier);
+ PREV_INSN (barrier) = new_insn;
+ }
+ }
}
/* Keep only one edge out and set proper flags. */
- while (src->succ->succ_next)
- remove_edge (src->succ);
- e = src->succ;
+ 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->probability = REG_BR_PROB_BASE;
e->count = src->count;
- /* We don't want a block to end on a line-number note since that has
- the potential of changing the code between -g and not -g. */
- while (GET_CODE (e->src->end) == NOTE
- && NOTE_LINE_NUMBER (e->src->end) >= 0)
- delete_insn (e->src->end);
-
if (e->dest != target)
redirect_edge_succ (e, target);
-
- return true;
-}
-
-/* Return last loop_beg note appearing after INSN, before start of next
- basic block. Return INSN if there are no such notes.
-
- When emitting jump to redirect a fallthru edge, it should always appear
- after the LOOP_BEG notes, as loop optimizer expect loop to either start by
- fallthru edge or jump following the LOOP_BEG note jumping to the loop exit
- test. */
-
-static rtx
-last_loop_beg_note (insn)
- rtx insn;
-{
- rtx last = insn;
-
- for (insn = NEXT_INSN (insn); insn && GET_CODE (insn) == NOTE
- && NOTE_LINE_NUMBER (insn) != NOTE_INSN_BASIC_BLOCK;
- insn = NEXT_INSN (insn))
- if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_BEG)
- last = insn;
-
- return last;
+ return 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 true if transformation succeeded. We still return false in case E
- already destinated TARGET and we didn't managed to simplify instruction
- stream. */
+/* 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. */
-bool
-redirect_edge_and_branch (e, target)
- edge e;
- basic_block target;
+static bool
+patch_jump_insn (rtx insn, rtx old_label, basic_block new_bb)
{
rtx tmp;
- rtx old_label = e->dest->head;
- basic_block src = e->src;
- rtx insn = src->end;
-
- if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH))
- return false;
-
- if (try_redirect_by_replacing_jump (e, target))
- return true;
-
- /* Do this fast path late, as we want above code to simplify for cases
- where called on single edge leaving basic block containing nontrivial
- jump insn. */
- else if (e->dest == target)
- return false;
-
- /* We can only redirect non-fallthru edges of jump insn. */
- if (e->flags & EDGE_FALLTHRU)
- return false;
- else if (GET_CODE (insn) != JUMP_INSN)
- return false;
-
/* Recognize a tablejump and adjust all matching cases. */
if (tablejump_p (insn, NULL, &tmp))
{
rtvec vec;
int j;
- rtx new_label = block_label (target);
+ rtx new_label = block_label (new_bb);
- if (target == EXIT_BLOCK_PTR)
+ if (new_bb == EXIT_BLOCK_PTR)
return false;
if (GET_CODE (PATTERN (tmp)) == ADDR_VEC)
vec = XVEC (PATTERN (tmp), 0);
++LABEL_NUSES (new_label);
}
- /* Handle casesi dispatch insns */
+ /* 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 (VOIDmode,
+ 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)
+ 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
|| returnjump_p (insn))
return false;
- /* If the insn doesn't go where we think, we're confused. */
- if (JUMP_LABEL (insn) != old_label)
- abort ();
-
- /* 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 (target), 0))
+ if (!currently_expanding_to_rtl || JUMP_LABEL (insn) == old_label)
{
- if (target == EXIT_BLOCK_PTR)
- return false;
- abort ();
+ /* 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);
+ 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 (rtl_dump_file)
- fprintf (rtl_dump_file, "Edge %i->%i redirected to %i\n",
+ 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)
- redirect_edge_succ_nodup (e, target);
+ e = redirect_edge_succ_nodup (e, target);
- return true;
+ return e;
}
-/* Like force_nonfallthru below, but additionally performs redirection
- Used by redirect_edge_and_branch_force. */
+/* Attempt to change code to redirect edge E to TARGET. Don't do that on
+ expense of adding new instructions or reordering basic blocks.
-basic_block
-force_nonfallthru_and_redirect (e, target)
- edge e;
- basic_block target;
-{
- basic_block jump_block, new_bb = NULL, src = e->src;
- rtx note;
- edge new_edge;
- int abnormal_edge_flags = 0;
+ 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;
+
+ if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH))
+ return NULL;
+
+ if (e->dest == target)
+ return e;
+
+ if ((ret = try_redirect_by_replacing_jump (e, target, false)) != NULL)
+ {
+ df_set_bb_dirty (src);
+ return ret;
+ }
+
+ ret = redirect_branch_edge (e, target);
+ if (!ret)
+ return NULL;
+
+ df_set_bb_dirty (src);
+ return ret;
+}
+
+/* Like force_nonfallthru below, but additionally performs redirection
+ Used by redirect_edge_and_branch_force. */
+
+static basic_block
+force_nonfallthru_and_redirect (edge e, basic_block target)
+{
+ basic_block jump_block, new_bb = NULL, src = e->src;
+ rtx note;
+ edge new_edge;
+ int abnormal_edge_flags = 0;
+ 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 an basic block afterwards to redirect fallthru edge. */
+ by creating a basic block afterwards to redirect fallthru edge. */
if (e->src != ENTRY_BLOCK_PTR && e->dest != EXIT_BLOCK_PTR
- && any_condjump_p (e->src->end)
- /* When called from cfglayout, fallthru edges do not
- neccessarily go to the next block. */
- && e->src->next_bb == e->dest
- && JUMP_LABEL (e->src->end) == e->dest->head)
+ && 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;
- if (!redirect_jump (e->src->end, block_label (target), 0))
- abort ();
- note = find_reg_note (e->src->end, REG_BR_PROB, NULL_RTX);
+ 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 = INTVAL (XEXP (note, 0));
/* 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.
+ one and create separate abnormal edge to original destination.
This allows bb-reorder to make such edge non-fallthru. */
- if (e->dest != target)
- abort ();
+ gcc_assert (e->dest == target);
abnormal_edge_flags = e->flags & ~(EDGE_FALLTHRU | EDGE_CAN_FALLTHRU);
e->flags &= EDGE_FALLTHRU | EDGE_CAN_FALLTHRU;
}
- else if (!(e->flags & EDGE_FALLTHRU))
- abort ();
- else if (e->src == ENTRY_BLOCK_PTR)
+ else
{
- /* 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 *pe1;
- basic_block bb = create_basic_block (e->dest->head, NULL, ENTRY_BLOCK_PTR);
+ gcc_assert (e->flags & EDGE_FALLTHRU);
+ if (e->src == ENTRY_BLOCK_PTR)
+ {
+ /* 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);
+
+ /* 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->succs); (tmp = ei_safe_edge (ei)); )
+ {
+ if (tmp == e)
+ {
+ VEC_unordered_remove (edge, ENTRY_BLOCK_PTR->succs, ei.index);
+ found = true;
+ break;
+ }
+ else
+ ei_next (&ei);
+ }
- /* 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 (pe1 = &ENTRY_BLOCK_PTR->succ; *pe1; pe1 = &(*pe1)->succ_next)
- if (*pe1 == e)
- {
- *pe1 = e->succ_next;
- break;
- }
- e->succ_next = 0;
- bb->succ = e;
- make_single_succ_edge (ENTRY_BLOCK_PTR, bb, EDGE_FALLTHRU);
+ gcc_assert (found);
+
+ VEC_safe_push (edge, gc, bb->succs, e);
+ make_single_succ_edge (ENTRY_BLOCK_PTR, bb, EDGE_FALLTHRU);
+ }
}
- if (e->src->succ->succ_next || abnormal_edge_flags)
+ if (EDGE_COUNT (e->src->succs) >= 2 || abnormal_edge_flags)
{
/* Create the new structures. */
- /* Position the new block correctly relative to loop notes. */
- note = last_loop_beg_note (e->src->end);
+ /* 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, ¬e))
+ note = BB_END (e->src);
note = NEXT_INSN (note);
- /* ... and ADDR_VECs. */
- if (note != NULL
- && GET_CODE (note) == CODE_LABEL
- && NEXT_INSN (note)
- && GET_CODE (NEXT_INSN (note)) == JUMP_INSN
- && (GET_CODE (PATTERN (NEXT_INSN (note))) == ADDR_DIFF_VEC
- || GET_CODE (PATTERN (NEXT_INSN (note))) == ADDR_VEC))
- note = NEXT_INSN (NEXT_INSN (note));
-
jump_block = create_basic_block (note, NULL, e->src);
jump_block->count = e->count;
jump_block->frequency = EDGE_FREQUENCY (e);
jump_block->loop_depth = target->loop_depth;
- if (target->global_live_at_start)
- {
- jump_block->global_live_at_start
- = OBSTACK_ALLOC_REG_SET (&flow_obstack);
- jump_block->global_live_at_end
- = OBSTACK_ALLOC_REG_SET (&flow_obstack);
- COPY_REG_SET (jump_block->global_live_at_start,
- target->global_live_at_start);
- COPY_REG_SET (jump_block->global_live_at_end,
- target->global_live_at_start);
- }
+ /* Make sure new block ends up in correct hot/cold section. */
+
+ BB_COPY_PARTITION (jump_block, e->src);
+ if (flag_reorder_blocks_and_partition
+ && targetm_common.have_named_sections
+ && JUMP_P (BB_END (jump_block))
+ && !any_condjump_p (BB_END (jump_block))
+ && (EDGE_SUCC (jump_block, 0)->flags & EDGE_CROSSING))
+ add_reg_note (BB_END (jump_block), REG_CROSSING_JUMP, NULL_RTX);
/* Wire edge in. */
new_edge = make_edge (e->src, jump_block, EDGE_FALLTHRU);
else
jump_block = e->src;
+ if (e->goto_locus && e->goto_block == NULL)
+ loc = e->goto_locus;
+ else
+ loc = 0;
e->flags &= ~EDGE_FALLTHRU;
if (target == EXIT_BLOCK_PTR)
{
- if (HAVE_return)
- emit_jump_insn_after (gen_return (), jump_block->end);
- else
- abort ();
+#ifdef HAVE_return
+ emit_jump_insn_after_setloc (gen_return (), BB_END (jump_block), loc);
+#else
+ gcc_unreachable ();
+#endif
}
else
{
rtx label = block_label (target);
- emit_jump_insn_after (gen_jump (label), jump_block->end);
- JUMP_LABEL (jump_block->end) = label;
+ emit_jump_insn_after_setloc (gen_jump (label), BB_END (jump_block), loc);
+ JUMP_LABEL (BB_END (jump_block)) = label;
LABEL_NUSES (label)++;
}
- emit_barrier_after (jump_block->end);
+ emit_barrier_after (BB_END (jump_block));
redirect_edge_succ_nodup (e, target);
if (abnormal_edge_flags)
make_edge (src, target, abnormal_edge_flags);
+ df_mark_solutions_dirty ();
return new_bb;
}
(and possibly create new basic block) to make edge non-fallthru.
Return newly created BB or NULL if none. */
-basic_block
-force_nonfallthru (e)
- edge e;
+static basic_block
+rtl_force_nonfallthru (edge e)
{
return force_nonfallthru_and_redirect (e, e->dest);
}
/* Redirect edge even at the expense of creating new jump insn or
basic block. Return new basic block if created, NULL otherwise.
- Abort if conversion is impossible. */
+ Conversion must be possible. */
-basic_block
-redirect_edge_and_branch_force (e, target)
- edge e;
- basic_block target;
+static basic_block
+rtl_redirect_edge_and_branch_force (edge e, basic_block target)
{
if (redirect_edge_and_branch (e, target)
|| e->dest == target)
/* 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);
}
/* 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. */
-void
-tidy_fallthru_edge (e, b, c)
- edge e;
- basic_block b, c;
+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 chastized and fixed.
+ 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 (b->end); q != c->head; q = NEXT_INSN (q))
+ 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 = b->end;
- if (GET_CODE (q) == JUMP_INSN
+ q = BB_END (b);
+ if (JUMP_P (q)
&& onlyjump_p (q)
&& (any_uncondjump_p (q)
- || (b->succ == e && e->succ_next == NULL)))
+ || single_succ_p (b)))
{
#ifdef HAVE_cc0
/* If this was a conditional jump, we need to also delete
#endif
q = PREV_INSN (q);
-
- /* We don't want a block to end on a line-number note since that has
- the potential of changing the code between -g and not -g. */
- while (GET_CODE (q) == NOTE && NOTE_LINE_NUMBER (q) >= 0)
- q = PREV_INSN (q);
}
/* Selectively unlink the sequence. */
- if (q != PREV_INSN (c->head))
- delete_insn_chain (NEXT_INSN (q), PREV_INSN (c->head));
+ if (q != PREV_INSN (BB_HEAD (c)))
+ delete_insn_chain (NEXT_INSN (q), PREV_INSN (BB_HEAD (c)), false);
e->flags |= EDGE_FALLTHRU;
}
-
-/* Fix up edges that now fall through, or rather should now fall through
- but previously required a jump around now deleted blocks. Simplify
- the search by only examining blocks numerically adjacent, since this
- is how find_basic_blocks created them. */
-
-void
-tidy_fallthru_edges ()
-{
- basic_block b, c;
-
- if (ENTRY_BLOCK_PTR->next_bb == EXIT_BLOCK_PTR)
- return;
-
- FOR_BB_BETWEEN (b, ENTRY_BLOCK_PTR->next_bb, EXIT_BLOCK_PTR->prev_bb, next_bb)
- {
- edge s;
-
- c = b->next_bb;
-
- /* We care about simple conditional or unconditional jumps with
- a single successor.
-
- If we had a conditional branch to the next instruction when
- find_basic_blocks was called, then there will only be one
- out edge for the block which ended with the conditional
- branch (since we do not create duplicate edges).
-
- Furthermore, the edge will be marked as a fallthru because we
- merge the flags for the duplicate edges. So we do not want to
- check that the edge is not a FALLTHRU edge. */
-
- if ((s = b->succ) != NULL
- && ! (s->flags & EDGE_COMPLEX)
- && s->succ_next == NULL
- && s->dest == c
- /* If the jump insn has side effects, we can't tidy the edge. */
- && (GET_CODE (b->end) != JUMP_INSN
- || onlyjump_p (b->end)))
- tidy_fallthru_edge (s, b, c);
- }
-}
\f
-/* Helper function for split_edge. Return true in case edge BB2 to BB1
- is back edge of syntactic loop. */
+/* Should move basic block BB after basic block AFTER. NIY. */
static bool
-back_edge_of_syntactic_loop_p (bb1, bb2)
- basic_block bb1, bb2;
+rtl_move_block_after (basic_block bb ATTRIBUTE_UNUSED,
+ basic_block after ATTRIBUTE_UNUSED)
{
- rtx insn;
- int count = 0;
- basic_block bb;
-
- if (bb1 == bb2)
- return true;
-
- /* ??? Could we guarantee that bb indices are monotone, so that we could
- just compare them? */
- for (bb = bb1; bb && bb != bb2; bb = bb->next_bb)
- continue;
-
- if (!bb)
- return false;
-
- for (insn = bb1->end; insn != bb2->head && count >= 0;
- insn = NEXT_INSN (insn))
- if (GET_CODE (insn) == NOTE)
- {
- if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_BEG)
- count++;
- else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_END)
- count--;
- }
-
- return count >= 0;
+ return false;
}
/* Split a (typically critical) edge. Return the new block.
- Abort on abnormal edges.
+ 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. */
-basic_block
-split_edge (edge_in)
- edge edge_in;
+static basic_block
+rtl_split_edge (edge edge_in)
{
basic_block bb;
rtx before;
/* Abnormal edges cannot be split. */
- if ((edge_in->flags & EDGE_ABNORMAL) != 0)
- abort ();
+ 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;
-
- for (e = edge_in->dest->pred; e; e = e->pred_next)
- if (e->flags & EDGE_FALLTHRU)
- break;
+ edge e = find_fallthru_edge (edge_in->dest->preds);
if (e)
force_nonfallthru (e);
}
- /* Create the basic block note.
-
- Where we place the note can have a noticeable impact on the generated
- code. Consider this cfg:
-
- E
- |
- 0
- / \
- +->1-->2--->E
- | |
- +--+
-
- If we need to insert an insn on the edge from block 0 to block 1,
- we want to ensure the instructions we insert are outside of any
- loop notes that physically sit between block 0 and block 1. Otherwise
- we confuse the loop optimizer into thinking the loop is a phony. */
-
- if (edge_in->dest != EXIT_BLOCK_PTR
- && PREV_INSN (edge_in->dest->head)
- && GET_CODE (PREV_INSN (edge_in->dest->head)) == NOTE
- && (NOTE_LINE_NUMBER (PREV_INSN (edge_in->dest->head))
- == NOTE_INSN_LOOP_BEG)
- && !back_edge_of_syntactic_loop_p (edge_in->dest, edge_in->src))
- before = PREV_INSN (edge_in->dest->head);
- else if (edge_in->dest != EXIT_BLOCK_PTR)
- before = edge_in->dest->head;
+ /* Create the basic block note. */
+ if (edge_in->dest != EXIT_BLOCK_PTR)
+ before = BB_HEAD (edge_in->dest);
else
before = NULL_RTX;
- bb = create_basic_block (before, NULL, edge_in->dest->prev_bb);
- bb->count = edge_in->count;
- bb->frequency = EDGE_FREQUENCY (edge_in);
-
- /* ??? This info is likely going to be out of date very soon. */
- if (edge_in->dest->global_live_at_start)
+ /* If this is a fall through edge to the exit block, the blocks might be
+ not adjacent, and the right place is the after the source. */
+ if (edge_in->flags & EDGE_FALLTHRU && edge_in->dest == EXIT_BLOCK_PTR)
{
- bb->global_live_at_start = OBSTACK_ALLOC_REG_SET (&flow_obstack);
- bb->global_live_at_end = OBSTACK_ALLOC_REG_SET (&flow_obstack);
- COPY_REG_SET (bb->global_live_at_start,
- edge_in->dest->global_live_at_start);
- COPY_REG_SET (bb->global_live_at_end,
- edge_in->dest->global_live_at_start);
+ 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
+ {
+ bb = create_basic_block (before, NULL, edge_in->dest->prev_bb);
+ /* ??? Why not edge_in->dest->prev_bb here? */
+ BB_COPY_PARTITION (bb, edge_in->dest);
}
make_single_succ_edge (bb, edge_in->dest, EDGE_FALLTHRU);
- /* For non-fallthry edges, we must adjust the predecessor's
+ /* For non-fallthru edges, we must adjust the predecessor's
jump instruction to target our new block. */
if ((edge_in->flags & EDGE_FALLTHRU) == 0)
{
- if (!redirect_edge_and_branch (edge_in, bb))
- abort ();
+ edge redirected = redirect_edge_and_branch (edge_in, bb);
+ gcc_assert (redirected);
}
else
- redirect_edge_succ (edge_in, bb);
+ {
+ if (edge_in->src != ENTRY_BLOCK_PTR)
+ {
+ /* 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
+ && 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;
}
CFG until commit_edge_insertions is called. */
void
-insert_insn_on_edge (pattern, e)
- rtx pattern;
- edge e;
+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. */
- if ((e->flags & EDGE_ABNORMAL) && EDGE_CRITICAL_P (e))
- abort ();
+ gcc_assert (!((e->flags & EDGE_ABNORMAL) && EDGE_CRITICAL_P (e)));
- if (e->insns == NULL_RTX)
+ if (e->insns.r == NULL_RTX)
start_sequence ();
else
- push_to_sequence (e->insns);
+ push_to_sequence (e->insns.r);
emit_insn (pattern);
- e->insns = get_insns ();
+ e->insns.r = get_insns ();
end_sequence ();
}
/* Update the CFG for the instructions queued on edge E. */
-static void
-commit_one_edge_insertion (e, watch_calls)
- edge e;
- int watch_calls;
+void
+commit_one_edge_insertion (edge e)
{
rtx before = NULL_RTX, after = NULL_RTX, insns, tmp, last;
- basic_block bb = NULL;
+ basic_block bb;
/* Pull the insns off the edge now since the edge might go away. */
- insns = e->insns;
- e->insns = NULL_RTX;
+ insns = e->insns.r;
+ e->insns.r = NULL_RTX;
- /* Special case -- avoid inserting code between call and storing
- its return value. */
- if (watch_calls && (e->flags & EDGE_FALLTHRU) && !e->dest->pred->pred_next
- && e->src != ENTRY_BLOCK_PTR
- && GET_CODE (e->src->end) == CALL_INSN)
+ /* 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)
{
- rtx next = next_nonnote_insn (e->src->end);
-
- after = e->dest->head;
- /* The first insn after the call may be a stack pop, skip it. */
- while (next
- && keep_with_call_p (next))
- {
- after = next;
- next = next_nonnote_insn (next);
- }
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 (!before && !after)
+
+ /* If the source has one successor and the edge is not abnormal,
+ insert there. Except for the entry block. */
+ else if ((e->flags & EDGE_ABNORMAL) == 0
+ && single_succ_p (e->src)
+ && e->src != ENTRY_BLOCK_PTR)
{
- /* Figure out where to put these things. If the destination has
- one predecessor, insert there. Except for the exit block. */
- if (e->dest->pred->pred_next == NULL && e->dest != EXIT_BLOCK_PTR)
- {
- 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;
- if (GET_CODE (tmp) == CODE_LABEL)
- tmp = NEXT_INSN (tmp);
- if (NOTE_INSN_BASIC_BLOCK_P (tmp))
- tmp = NEXT_INSN (tmp);
- if (tmp == bb->head)
- before = tmp;
- else if (tmp)
- after = PREV_INSN (tmp);
- else
- after = get_last_insn ();
- }
+ bb = e->src;
- /* If the source has one successor and the edge is not abnormal,
- insert there. Except for the entry block. */
- else if ((e->flags & EDGE_ABNORMAL) == 0
- && e->src->succ->succ_next == NULL
- && e->src != ENTRY_BLOCK_PTR)
- {
- 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 (GET_CODE (bb->end) == JUMP_INSN)
- for (before = bb->end;
- GET_CODE (PREV_INSN (before)) == NOTE
- && NOTE_LINE_NUMBER (PREV_INSN (before)) ==
- NOTE_INSN_LOOP_BEG; before = PREV_INSN (before))
- ;
- else
- {
- /* We'd better be fallthru, or we've lost track of what's what. */
- if ((e->flags & EDGE_FALLTHRU) == 0)
- abort ();
+ /* 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.
- after = bb->end;
- }
- }
- /* Otherwise we must split the edge. */
+ 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
{
- bb = split_edge (e);
- after = bb->end;
+ /* We'd better be fallthru, or we've lost track of what's what. */
+ gcc_assert (e->flags & EDGE_FALLTHRU);
+
+ after = BB_END (bb);
}
}
- /* Now that we've found the spot, do the insertion. */
+ /* Otherwise we must split the edge. */
+ else
+ {
+ bb = split_edge (e);
+ after = BB_END (bb);
+
+ if (flag_reorder_blocks_and_partition
+ && targetm_common.have_named_sections
+ && e->src != ENTRY_BLOCK_PTR
+ && BB_PARTITION (e->src) == BB_COLD_PARTITION
+ && !(e->flags & EDGE_CROSSING)
+ && JUMP_P (after)
+ && !any_condjump_p (after)
+ && (single_succ_edge (bb)->flags & EDGE_CROSSING))
+ add_reg_note (after, REG_CROSSING_JUMP, NULL_RTX);
+ }
+ /* Now that we've found the spot, do the insertion. */
if (before)
{
- emit_insn_before (insns, before);
+ emit_insn_before_noloc (insns, before, bb);
last = prev_nonnote_insn (before);
}
else
- last = emit_insn_after (insns, after);
+ 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. */
+ This is not currently a problem because this only happens
+ for the (single) epilogue, which already has a fallthru edge
+ to EXIT. */
- e = bb->succ;
- if (e->dest != EXIT_BLOCK_PTR
- || e->succ_next != NULL || (e->flags & EDGE_FALLTHRU) == 0)
- abort ();
+ e = single_succ_edge (bb);
+ gcc_assert (e->dest == EXIT_BLOCK_PTR
+ && single_succ_p (bb) && (e->flags & EDGE_FALLTHRU));
e->flags &= ~EDGE_FALLTHRU;
emit_barrier_after (last);
if (before)
delete_insn (before);
}
- else if (GET_CODE (last) == JUMP_INSN)
- abort ();
-
- /* Mark the basic block for find_sub_basic_blocks. */
- bb->aux = &bb->aux;
+ else
+ gcc_assert (!JUMP_P (last));
}
/* Update the CFG for all queued instructions. */
void
-commit_edge_insertions ()
+commit_edge_insertions (void)
{
basic_block bb;
- sbitmap blocks;
- bool changed = false;
#ifdef ENABLE_CHECKING
verify_flow_info ();
FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, EXIT_BLOCK_PTR, next_bb)
{
- edge e, next;
+ edge e;
+ edge_iterator ei;
- for (e = bb->succ; e; e = next)
- {
- next = e->succ_next;
- if (e->insns)
- {
- changed = true;
- commit_one_edge_insertion (e, false);
- }
- }
+ FOR_EACH_EDGE (e, ei, bb->succs)
+ if (e->insns.r)
+ commit_one_edge_insertion (e);
}
-
- if (!changed)
- return;
-
- blocks = sbitmap_alloc (last_basic_block);
- sbitmap_zero (blocks);
- FOR_EACH_BB (bb)
- if (bb->aux)
- {
- SET_BIT (blocks, bb->index);
- /* Check for forgotten bb->aux values before commit_edge_insertions
- call. */
- if (bb->aux != &bb->aux)
- abort ();
- bb->aux = NULL;
- }
- find_many_sub_basic_blocks (blocks);
- sbitmap_free (blocks);
}
\f
-/* Update the CFG for all queued instructions, taking special care of inserting
- code on edges between call and storing its return value. */
-
-void
-commit_edge_insertions_watch_calls ()
-{
- basic_block bb;
- sbitmap blocks;
- bool changed = false;
-
-#ifdef ENABLE_CHECKING
- verify_flow_info ();
-#endif
-
- FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, EXIT_BLOCK_PTR, next_bb)
- {
- edge e, next;
-
- for (e = bb->succ; e; e = next)
- {
- next = e->succ_next;
- if (e->insns)
- {
- changed = true;
- commit_one_edge_insertion (e, true);
- }
- }
- }
- if (!changed)
- return;
-
- blocks = sbitmap_alloc (last_basic_block);
- sbitmap_zero (blocks);
- FOR_EACH_BB (bb)
- if (bb->aux)
- {
- SET_BIT (blocks, bb->index);
- /* Check for forgotten bb->aux values before commit_edge_insertions
- call. */
- if (bb->aux != &bb->aux)
- abort ();
- bb->aux = NULL;
- }
- find_many_sub_basic_blocks (blocks);
- sbitmap_free (blocks);
-}
-\f
-/* Print out one basic block with live information at start and end. */
+/* Print out RTL-specific basic block information (live information
+ at start and end). */
-void
-dump_bb (bb, outf)
- basic_block bb;
- FILE *outf;
+static void
+rtl_dump_bb (basic_block bb, FILE *outf, int indent, int flags ATTRIBUTE_UNUSED)
{
rtx insn;
rtx last;
- edge e;
+ char *s_indent;
- fprintf (outf, ";; Basic block %d, loop depth %d, count ",
- bb->index, bb->loop_depth);
- fprintf (outf, HOST_WIDEST_INT_PRINT_DEC, (HOST_WIDEST_INT) bb->count);
- putc ('\n', outf);
+ s_indent = (char *) alloca ((size_t) indent + 1);
+ memset (s_indent, ' ', (size_t) indent);
+ s_indent[indent] = '\0';
- fputs (";; Predecessors: ", outf);
- for (e = bb->pred; e; e = e->pred_next)
- dump_edge_info (outf, e, 0);
- putc ('\n', outf);
-
- fputs (";; Registers live at start:", outf);
- dump_regset (bb->global_live_at_start, outf);
- putc ('\n', outf);
+ if (df)
+ {
+ df_dump_top (bb, outf);
+ putc ('\n', outf);
+ }
- for (insn = bb->head, last = NEXT_INSN (bb->end); insn != last;
+ for (insn = BB_HEAD (bb), last = NEXT_INSN (BB_END (bb)); insn != last;
insn = NEXT_INSN (insn))
print_rtl_single (outf, insn);
- fputs (";; Registers live at end:", outf);
- dump_regset (bb->global_live_at_end, outf);
- putc ('\n', outf);
-
- fputs (";; Successors: ", outf);
- for (e = bb->succ; e; e = e->succ_next)
- dump_edge_info (outf, e, 1);
- putc ('\n', outf);
-}
-
-void
-debug_bb (bb)
- basic_block bb;
-{
- dump_bb (bb, stderr);
-}
+ if (df)
+ {
+ df_dump_bottom (bb, outf);
+ putc ('\n', outf);
+ }
-basic_block
-debug_bb_n (n)
- int n;
-{
- basic_block bb = BASIC_BLOCK (n);
- dump_bb (bb, stderr);
- return bb;
}
\f
/* Like print_rtl, but also print out live information for the start of each
basic block. */
void
-print_rtl_with_bb (outf, rtx_first)
- FILE *outf;
- rtx rtx_first;
+print_rtl_with_bb (FILE *outf, const_rtx rtx_first)
{
- rtx tmp_rtx;
-
+ 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
- = (basic_block *) xcalloc (max_uid, sizeof (basic_block));
- basic_block *end
- = (basic_block *) xcalloc (max_uid, sizeof (basic_block));
- enum bb_state *in_bb_p
- = (enum bb_state *) xcalloc (max_uid, sizeof (enum bb_state));
+ 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;
+ if (df)
+ df_dump_start (outf);
+
FOR_EACH_BB_REVERSE (bb)
{
rtx x;
- start[INSN_UID (bb->head)] = bb;
- end[INSN_UID (bb->end)] = bb;
- for (x = bb->head; x != NULL_RTX; x = NEXT_INSN (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;
state = IN_ONE_BB;
in_bb_p[INSN_UID (x)] = state;
- if (x == bb->end)
+ if (x == BB_END (bb))
break;
}
}
for (tmp_rtx = rtx_first; NULL != tmp_rtx; tmp_rtx = NEXT_INSN (tmp_rtx))
{
int did_output;
-
if ((bb = start[INSN_UID (tmp_rtx)]) != NULL)
{
- fprintf (outf, ";; Start of basic block %d, registers live:",
- bb->index);
- dump_regset (bb->global_live_at_start, outf);
- putc ('\n', outf);
+ edge e;
+ edge_iterator ei;
+
+ fprintf (outf, ";; Start of basic block (");
+ FOR_EACH_EDGE (e, ei, bb->preds)
+ fprintf (outf, " %d", e->src->index);
+ fprintf (outf, ") -> %d\n", bb->index);
+
+ if (df)
+ {
+ df_dump_top (bb, outf);
+ putc ('\n', outf);
+ }
+ FOR_EACH_EDGE (e, ei, bb->preds)
+ {
+ fputs (";; Pred edge ", outf);
+ dump_edge_info (outf, e, 0);
+ fputc ('\n', outf);
+ }
}
if (in_bb_p[INSN_UID (tmp_rtx)] == NOT_IN_BB
- && GET_CODE (tmp_rtx) != NOTE
- && GET_CODE (tmp_rtx) != BARRIER)
+ && !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 ((bb = end[INSN_UID (tmp_rtx)]) != NULL)
{
- fprintf (outf, ";; End of basic block %d, registers live:\n",
- bb->index);
- dump_regset (bb->global_live_at_end, outf);
+ edge e;
+ edge_iterator ei;
+
+ fprintf (outf, ";; End of basic block %d -> (", bb->index);
+ FOR_EACH_EDGE (e, ei, bb->succs)
+ fprintf (outf, " %d", e->dest->index);
+ fprintf (outf, ")\n");
+
+ if (df)
+ {
+ df_dump_bottom (bb, outf);
+ putc ('\n', outf);
+ }
putc ('\n', outf);
+ FOR_EACH_EDGE (e, ei, bb->succs)
+ {
+ fputs (";; Succ edge ", outf);
+ dump_edge_info (outf, e, 1);
+ fputc ('\n', outf);
+ }
}
-
if (did_output)
putc ('\n', outf);
}
free (in_bb_p);
}
- if (current_function_epilogue_delay_list != 0)
+ if (crtl->epilogue_delay_list != 0)
{
fprintf (outf, "\n;; Insns in epilogue delay list:\n\n");
- for (tmp_rtx = current_function_epilogue_delay_list; tmp_rtx != 0;
+ for (tmp_rtx = crtl->epilogue_delay_list; tmp_rtx != 0;
tmp_rtx = XEXP (tmp_rtx, 1))
print_rtl_single (outf, XEXP (tmp_rtx, 0));
}
}
\f
void
-update_br_prob_note (bb)
- basic_block bb;
+update_br_prob_note (basic_block bb)
{
rtx note;
- if (GET_CODE (bb->end) != JUMP_INSN)
+ if (!JUMP_P (BB_END (bb)))
return;
- note = find_reg_note (bb->end, REG_BR_PROB, NULL_RTX);
+ note = find_reg_note (BB_END (bb), REG_BR_PROB, NULL_RTX);
if (!note || INTVAL (XEXP (note, 0)) == BRANCH_EDGE (bb)->probability)
return;
XEXP (note, 0) = GEN_INT (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;
+}
\f
-/* Verify the CFG consistency. This function check some CFG invariants and
- aborts when something is wrong. Hope that this function will help to
- convert many optimization passes to preserve CFG consistent.
+/* Verify the CFG and RTL consistency common for both underlying RTL and
+ cfglayout RTL.
Currently it does following checks:
- - test head/end pointers
- overlapping of basic blocks
- - edge list correctness
+ - 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
- - 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
+ - verify that no fall_thru edge crosses hot/cold partition boundaries
+ - verify that there are no pending RTL branch predictions
In future it can be extended check a lot of other stuff as well
(reachability of basic blocks, life information, etc. etc.). */
-void
-verify_flow_info ()
+static int
+rtl_verify_flow_info_1 (void)
{
- const int max_uid = get_max_uid ();
- const rtx rtx_first = get_insns ();
- rtx last_head = get_last_insn ();
- basic_block *bb_info, *last_visited;
- size_t *edge_checksum;
rtx x;
- int num_bb_notes, err = 0;
- basic_block bb, last_bb_seen;
-
- bb_info = (basic_block *) xcalloc (max_uid, sizeof (basic_block));
- last_visited = (basic_block *) xcalloc (last_basic_block + 2,
- sizeof (basic_block));
- edge_checksum = (size_t *) xcalloc (last_basic_block + 2, sizeof (size_t));
+ int err = 0;
+ basic_block bb;
- /* Check bb chain & numbers. */
- last_bb_seen = ENTRY_BLOCK_PTR;
- FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR->next_bb, NULL, next_bb)
+ /* Check the general integrity of the basic blocks. */
+ FOR_EACH_BB_REVERSE (bb)
{
- if (bb != EXIT_BLOCK_PTR
- && bb != BASIC_BLOCK (bb->index))
- {
- error ("bb %d on wrong place", bb->index);
- err = 1;
- }
+ rtx insn;
- if (bb->prev_bb != last_bb_seen)
+ if (!(bb->flags & BB_RTL))
{
- error ("prev_bb of %d should be %d, not %d",
- bb->index, last_bb_seen->index, bb->prev_bb->index);
+ error ("BB_RTL flag not set for block %d", bb->index);
err = 1;
}
- last_bb_seen = bb;
+ 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->il.rtl->header; 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->il.rtl->footer; 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;
+ }
}
+ /* Now check the basic blocks (boundaries etc.) */
FOR_EACH_BB_REVERSE (bb)
{
- rtx head = bb->head;
- rtx end = bb->end;
-
- /* Verify the end of the basic block is in the INSN chain. */
- for (x = last_head; x != NULL_RTX; x = PREV_INSN (x))
- if (x == end)
- break;
+ int n_fallthru = 0, n_eh = 0, n_call = 0, n_abnormal = 0, n_branch = 0;
+ edge e, fallthru = NULL;
+ rtx note;
+ edge_iterator ei;
- if (!x)
+ 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)))
{
- error ("end insn %d for block %d not found in the insn stream",
- INSN_UID (end), bb->index);
- err = 1;
+ if (INTVAL (XEXP (note, 0)) != BRANCH_EDGE (bb)->probability
+ && profile_status != PROFILE_ABSENT)
+ {
+ error ("verify_flow_info: REG_BR_PROB does not match cfg %wi %i",
+ INTVAL (XEXP (note, 0)), BRANCH_EDGE (bb)->probability);
+ 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))
+ FOR_EACH_EDGE (e, ei, bb->succs)
{
- /* While walking over the insn chain, verify insns appear
- in only one basic block and initialize the BB_INFO array
- used by other passes. */
- if (bb_info[INSN_UID (x)] != NULL)
+ if (e->flags & EDGE_FALLTHRU)
{
- error ("insn %d is in multiple basic blocks (%d and %d)",
- INSN_UID (x), bb->index, bb_info[INSN_UID (x)]->index);
- err = 1;
+ n_fallthru++, fallthru = e;
+ if ((e->flags & EDGE_CROSSING)
+ || (BB_PARTITION (e->src) != BB_PARTITION (e->dest)
+ && e->src != ENTRY_BLOCK_PTR
+ && e->dest != EXIT_BLOCK_PTR))
+ {
+ error ("fallthru edge crosses section boundary (bb %i)",
+ e->src->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 = x;
- }
-
- /* Now check the basic blocks (boundaries etc.) */
- FOR_EACH_BB_REVERSE (bb)
- {
- int n_fallthru = 0, n_eh = 0, n_call = 0, n_abnormal = 0, n_branch = 0;
- edge e;
- rtx note;
-
- if (INSN_P (bb->end)
- && (note = find_reg_note (bb->end, REG_BR_PROB, NULL_RTX))
- && bb->succ && bb->succ->succ_next
- && any_condjump_p (bb->end))
- {
- if (INTVAL (XEXP (note, 0)) != BRANCH_EDGE (bb)->probability)
- {
- error ("verify_flow_info: REG_BR_PROB does not match cfg %i %i",
- INTVAL (XEXP (note, 0)), BRANCH_EDGE (bb)->probability);
- err = 1;
- }
- }
- if (bb->count < 0)
- {
- error ("verify_flow_info: Wrong count of block %i %i",
- bb->index, (int)bb->count);
- err = 1;
- }
- if (bb->frequency < 0)
- {
- error ("verify_flow_info: Wrong frequency of block %i %i",
- bb->index, bb->frequency);
- err = 1;
- }
- for (e = bb->succ; e; e = e->succ_next)
- {
- if (last_visited [e->dest->index + 2] == bb)
- {
- error ("verify_flow_info: Duplicate edge %i->%i",
- e->src->index, e->dest->index);
- err = 1;
- }
- if (e->probability < 0 || e->probability > REG_BR_PROB_BASE)
- {
- error ("verify_flow_info: Wrong probability of edge %i->%i %i",
- e->src->index, e->dest->index, e->probability);
- err = 1;
- }
- if (e->count < 0)
- {
- error ("verify_flow_info: Wrong count of edge %i->%i %i",
- e->src->index, e->dest->index, (int)e->count);
- err = 1;
- }
-
- last_visited [e->dest->index + 2] = bb;
-
- if (e->flags & EDGE_FALLTHRU)
- n_fallthru++;
-
- if ((e->flags & ~(EDGE_DFS_BACK | EDGE_CAN_FALLTHRU | EDGE_IRREDUCIBLE_LOOP)) == 0)
- n_branch++;
+ if ((e->flags & ~(EDGE_DFS_BACK
+ | EDGE_CAN_FALLTHRU
+ | EDGE_IRREDUCIBLE_LOOP
+ | EDGE_LOOP_EXIT
+ | EDGE_CROSSING)) == 0)
+ n_branch++;
if (e->flags & EDGE_ABNORMAL_CALL)
n_call++;
n_eh++;
else if (e->flags & EDGE_ABNORMAL)
n_abnormal++;
-
- if ((e->flags & EDGE_FALLTHRU)
- && e->src != ENTRY_BLOCK_PTR
- && e->dest != EXIT_BLOCK_PTR)
- {
- 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 (e->src->end); insn != e->dest->head;
- insn = NEXT_INSN (insn))
- if (GET_CODE (insn) == BARRIER
-#ifndef CASE_DROPS_THROUGH
- || INSN_P (insn)
-#else
- || (INSN_P (insn) && ! JUMP_TABLE_DATA_P (insn))
-#endif
- )
- {
- 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;
- }
- }
-
- if (e->src != bb)
- {
- error ("verify_flow_info: Basic block %d succ edge is corrupted",
- bb->index);
- fprintf (stderr, "Predecessor: ");
- dump_edge_info (stderr, e, 0);
- fprintf (stderr, "\nSuccessor: ");
- dump_edge_info (stderr, e, 1);
- fprintf (stderr, "\n");
- err = 1;
- }
-
- edge_checksum[e->dest->index + 2] += (size_t) e;
}
- if (n_eh && GET_CODE (PATTERN (bb->end)) != RESX
- && !find_reg_note (bb->end, REG_EH_REGION, NULL_RTX))
+ if (n_eh && !find_reg_note (BB_END (bb), REG_EH_REGION, NULL_RTX))
{
- error ("Missing REG_EH_REGION note in the end of bb %i", bb->index);
+ error ("missing REG_EH_REGION note in the end of bb %i", bb->index);
err = 1;
}
- if (n_branch
- && (GET_CODE (bb->end) != JUMP_INSN
- || (n_branch > 1 && (any_uncondjump_p (bb->end)
- || any_condjump_p (bb->end)))))
+ if (n_eh > 1)
{
- error ("Too many outgoing branch edges from bb %i", bb->index);
+ error ("too many eh edges %i", bb->index);
err = 1;
}
- if (n_fallthru && any_uncondjump_p (bb->end))
+ if (n_branch
+ && (!JUMP_P (BB_END (bb))
+ || (n_branch > 1 && (any_uncondjump_p (BB_END (bb))
+ || any_condjump_p (BB_END (bb))))))
{
- error ("Fallthru edge after unconditional jump %i", bb->index);
+ error ("too many outgoing branch edges from bb %i", bb->index);
err = 1;
}
- if (n_branch != 1 && any_uncondjump_p (bb->end))
+ if (n_fallthru && any_uncondjump_p (BB_END (bb)))
{
- error ("Wrong amount of branch edges after unconditional jump %i", bb->index);
+ error ("fallthru edge after unconditional jump %i", bb->index);
err = 1;
}
- if (n_branch != 1 && any_condjump_p (bb->end)
- && JUMP_LABEL (bb->end) != bb->next_bb->head)
+ if (n_branch != 1 && any_uncondjump_p (BB_END (bb)))
{
- error ("Wrong amount of branch edges after conditional jump %i", bb->index);
+ error ("wrong number of branch edges after unconditional jump %i",
+ bb->index);
err = 1;
}
- if (n_call && GET_CODE (bb->end) != CALL_INSN)
+ if (n_branch != 1 && any_condjump_p (BB_END (bb))
+ && JUMP_LABEL (BB_END (bb)) != BB_HEAD (fallthru->dest))
{
- error ("Call edges for non-call insn in bb %i", bb->index);
+ error ("wrong amount of branch edges after conditional jump %i",
+ bb->index);
err = 1;
}
- if (n_abnormal
- && (GET_CODE (bb->end) != CALL_INSN && n_call != n_abnormal)
- && (GET_CODE (bb->end) != JUMP_INSN
- || any_condjump_p (bb->end)
- || any_uncondjump_p (bb->end)))
+ if (n_call && !CALL_P (BB_END (bb)))
{
- error ("Abnormal edges for no purpose in bb %i", bb->index);
+ error ("call edges for non-call insn in bb %i", bb->index);
err = 1;
}
-
- if (!n_fallthru)
- {
- rtx insn;
-
- /* Ensure existence of barrier in BB with no fallthru edges. */
- for (insn = bb->end; !insn || GET_CODE (insn) != BARRIER;
- insn = NEXT_INSN (insn))
- if (!insn
- || (GET_CODE (insn) == NOTE
- && NOTE_LINE_NUMBER (insn) == NOTE_INSN_BASIC_BLOCK))
- {
- error ("missing barrier after block %i", bb->index);
- err = 1;
- break;
- }
- }
-
- for (e = bb->pred; e; e = e->pred_next)
+ if (n_abnormal
+ && (!CALL_P (BB_END (bb)) && n_call != n_abnormal)
+ && (!JUMP_P (BB_END (bb))
+ || any_condjump_p (BB_END (bb))
+ || any_uncondjump_p (BB_END (bb))))
{
- if (e->dest != bb)
- {
- error ("basic block %d pred edge is corrupted", bb->index);
- fputs ("Predecessor: ", stderr);
- dump_edge_info (stderr, e, 0);
- fputs ("\nSuccessor: ", stderr);
- dump_edge_info (stderr, e, 1);
- fputc ('\n', stderr);
- err = 1;
- }
- edge_checksum[e->dest->index + 2] -= (size_t) e;
+ error ("abnormal edges for no purpose in bb %i", bb->index);
+ err = 1;
}
- for (x = bb->head; x != NEXT_INSN (bb->end); x = NEXT_INSN (x))
- if (BLOCK_FOR_INSN (x) != bb)
+ for (x = BB_HEAD (bb); x != NEXT_INSN (BB_END (bb)); x = NEXT_INSN (x))
+ /* We may have a barrier inside a basic block before dead code
+ elimination. There is no BLOCK_FOR_INSN field in a barrier. */
+ if (!BARRIER_P (x) && BLOCK_FOR_INSN (x) != bb)
{
debug_rtx (x);
if (! BLOCK_FOR_INSN (x))
}
/* OK pointers are correct. Now check the header of basic
- block. It ought to contain optional CODE_LABEL followed
+ block. It ought to contain optional CODE_LABEL followed
by NOTE_BASIC_BLOCK. */
- x = bb->head;
- if (GET_CODE (x) == CODE_LABEL)
+ x = BB_HEAD (bb);
+ if (LABEL_P (x))
{
- if (bb->end == x)
+ if (BB_END (bb) == x)
{
error ("NOTE_INSN_BASIC_BLOCK is missing for block %d",
bb->index);
err = 1;
}
- if (bb->end == x)
- /* Do checks for empty blocks her. e */
+ if (BB_END (bb) == x)
+ /* Do checks for empty blocks here. */
;
else
for (x = NEXT_INSN (x); x; x = NEXT_INSN (x))
err = 1;
}
- if (x == bb->end)
+ if (x == BB_END (bb))
break;
if (control_flow_insn_p (x))
}
}
- /* Complete edge checksumming for ENTRY and EXIT. */
- {
- edge e;
+ /* Clean up. */
+ return err;
+}
- for (e = ENTRY_BLOCK_PTR->succ; e ; e = e->succ_next)
- edge_checksum[e->dest->index + 2] += (size_t) e;
+/* Verify the CFG and RTL consistency common for both underlying RTL and
+ cfglayout RTL.
- for (e = EXIT_BLOCK_PTR->pred; e ; e = e->pred_next)
- edge_checksum[e->dest->index + 2] -= (size_t) e;
- }
+ Currently it does following checks:
+ - all checks of rtl_verify_flow_info_1
+ - test head/end pointers
+ - 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. */
- FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, NULL, next_bb)
- if (edge_checksum[bb->index + 2])
- {
- error ("basic block %i edge lists are corrupted", bb->index);
- err = 1;
- }
+static int
+rtl_verify_flow_info (void)
+{
+ basic_block bb;
+ int err = rtl_verify_flow_info_1 ();
+ rtx x;
+ rtx last_head = get_last_insn ();
+ basic_block *bb_info;
+ int num_bb_notes;
+ const rtx rtx_first = get_insns ();
+ basic_block last_bb_seen = ENTRY_BLOCK_PTR, curr_bb = NULL;
+ const int max_uid = get_max_uid ();
+
+ bb_info = XCNEWVEC (basic_block, max_uid);
+
+ FOR_EACH_BB_REVERSE (bb)
+ {
+ edge e;
+ 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);
+
+ 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
+ && e->dest != EXIT_BLOCK_PTR)
+ {
+ 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;
+ }
+ }
+ }
+
+ 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);
num_bb_notes = 0;
last_bb_seen = ENTRY_BLOCK_PTR;
num_bb_notes++;
if (bb != last_bb_seen->next_bb)
- internal_error ("basic blocks not numbered consecutively");
+ internal_error ("basic blocks not laid down consecutively");
- last_bb_seen = bb;
+ curr_bb = last_bb_seen = bb;
}
- if (!bb_info[INSN_UID (x)])
+ if (!curr_bb)
{
switch (GET_CODE (x))
{
break;
case CODE_LABEL:
- /* An addr_vec is placed outside any block block. */
+ /* An addr_vec is placed outside any basic block. */
if (NEXT_INSN (x)
- && GET_CODE (NEXT_INSN (x)) == JUMP_INSN
- && (GET_CODE (PATTERN (NEXT_INSN (x))) == ADDR_DIFF_VEC
- || GET_CODE (PATTERN (NEXT_INSN (x))) == ADDR_VEC))
+ && JUMP_TABLE_DATA_P (NEXT_INSN (x)))
x = NEXT_INSN (x);
/* But in any case, non-deletable labels can appear anywhere. */
}
}
- if (INSN_P (x)
- && GET_CODE (x) == JUMP_INSN
+ if (JUMP_P (x)
&& returnjump_p (x) && ! condjump_p (x)
- && ! (NEXT_INSN (x) && GET_CODE (NEXT_INSN (x)) == BARRIER))
+ && ! (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)
+ if (num_bb_notes != n_basic_blocks - NUM_FIXED_BLOCKS)
internal_error
("number of bb notes in insn chain (%d) != n_basic_blocks (%d)",
num_bb_notes, n_basic_blocks);
- if (err)
- internal_error ("verify_flow_info failed");
-
- /* Clean up. */
- free (bb_info);
- free (last_visited);
- free (edge_checksum);
+ return err;
}
\f
/* Assume that the preceding pass has possibly eliminated jump instructions
Return true if any edges are eliminated. */
bool
-purge_dead_edges (bb)
- basic_block bb;
+purge_dead_edges (basic_block bb)
{
- edge e, next;
- rtx insn = bb->end, note;
+ 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 (GET_CODE (insn) == INSN
+ if (NONJUMP_INSN_P (insn)
&& (note = find_reg_note (insn, REG_EH_REGION, NULL)))
{
rtx eqnote;
}
/* Cleanup abnormal edges caused by exceptions or non-local gotos. */
- for (e = bb->succ; e; e = next)
+ for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
{
- next = e->succ_next;
- if (e->flags & EDGE_EH)
+ 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 (can_throw_internal (bb->end))
- continue;
+ if (!CALL_P (insn))
+ remove = true;
+ else if (can_nonlocal_goto (insn))
+ ;
+ else if ((e->flags & EDGE_EH) && can_throw_internal (insn))
+ ;
+ else
+ remove = true;
}
- else if (e->flags & EDGE_ABNORMAL_CALL)
+ else if (e->flags & EDGE_EH)
+ remove = !can_throw_internal (insn);
+
+ if (remove)
{
- if (GET_CODE (bb->end) == CALL_INSN
- && (! (note = find_reg_note (insn, REG_EH_REGION, NULL))
- || INTVAL (XEXP (note, 0)) >= 0))
- continue;
+ remove_edge (e);
+ df_set_bb_dirty (bb);
+ purged = true;
}
else
- continue;
-
- remove_edge (e);
- bb->flags |= BB_DIRTY;
- purged = true;
+ ei_next (&ei);
}
- if (GET_CODE (insn) == JUMP_INSN)
+ 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)
remove_note (insn, note);
}
- for (e = bb->succ; e; e = next)
+ for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
{
- next = e->succ_next;
-
/* Avoid abnormal flags to leak from computed jumps turned
into simplejumps. */
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. */
- continue;
+ {
+ ei_next (&ei);
+ continue;
+ }
else if (e->dest != EXIT_BLOCK_PTR
- && e->dest->head == JUMP_LABEL (insn))
+ && BB_HEAD (e->dest) == JUMP_LABEL (insn))
/* If the destination block is the target of the jump,
keep the edge. */
- continue;
+ {
+ ei_next (&ei);
+ continue;
+ }
else if (e->dest == EXIT_BLOCK_PTR && returnjump_p (insn))
/* If the destination block is the exit block, and this
instruction is a return, then keep the edge. */
- continue;
+ {
+ 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. */
- continue;
+ 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. */
- bb->flags |= BB_DIRTY;
+ df_set_bb_dirty (bb);
purged = true;
remove_edge (e);
}
- if (!bb->succ || !purged)
+ if (EDGE_COUNT (bb->succs) == 0 || !purged)
return purged;
- if (rtl_dump_file)
- fprintf (rtl_dump_file, "Purged edges from bb %i\n", bb->index);
+ if (dump_file)
+ fprintf (dump_file, "Purged edges from bb %i\n", bb->index);
if (!optimize)
return purged;
/* Redistribute probabilities. */
- if (!bb->succ->succ_next)
+ if (single_succ_p (bb))
{
- bb->succ->probability = REG_BR_PROB_BASE;
- bb->succ->count = bb->count;
+ single_succ_edge (bb)->probability = REG_BR_PROB_BASE;
+ single_succ_edge (bb)->count = bb->count;
}
else
{
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. */
- for (e = bb->succ; e && (e->flags & (EDGE_COMPLEX | EDGE_FALLTHRU));
- e = e->succ_next)
- ;
+ found = false;
+ FOR_EACH_EDGE (e, ei, bb->succs)
+ if (! (e->flags & (EDGE_COMPLEX | EDGE_FALLTHRU)))
+ {
+ found = true;
+ break;
+ }
- if (!e)
+ if (!found)
return purged;
- for (e = bb->succ; e; e = next)
+ /* 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)); )
{
- next = e->succ_next;
- if (!(e->flags & EDGE_FALLTHRU))
+ if (!(e->flags & (EDGE_FALLTHRU | EDGE_FAKE)))
{
- bb->flags |= BB_DIRTY;
+ df_set_bb_dirty (bb);
remove_edge (e);
purged = true;
}
+ else
+ ei_next (&ei);
}
- if (!bb->succ || bb->succ->succ_next)
- abort ();
+ gcc_assert (single_succ_p (bb));
- bb->succ->probability = REG_BR_PROB_BASE;
- bb->succ->count = bb->count;
+ single_succ_edge (bb)->probability = REG_BR_PROB_BASE;
+ single_succ_edge (bb)->count = bb->count;
- if (rtl_dump_file)
- fprintf (rtl_dump_file, "Purged non-fallthru edges from bb %i\n",
+ if (dump_file)
+ fprintf (dump_file, "Purged non-fallthru edges from bb %i\n",
bb->index);
return purged;
}
true if some edge has been eliminated. */
bool
-purge_all_dead_edges (update_life_p)
- int update_life_p;
+purge_all_dead_edges (void)
{
int purged = false;
- sbitmap blocks = 0;
basic_block bb;
- if (update_life_p)
+ FOR_EACH_BB (bb)
{
- blocks = sbitmap_alloc (last_basic_block);
- sbitmap_zero (blocks);
+ 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 (bb)
{
- bool purged_here = purge_dead_edges (bb);
+ 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;
- purged |= purged_here;
- if (purged_here && update_life_p)
- SET_BIT (blocks, bb->index);
+ 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);
+ }
}
- if (update_life_p && purged)
- update_life_info (blocks, UPDATE_LIFE_GLOBAL,
- PROP_DEATH_NOTES | PROP_SCAN_DEAD_CODE
- | PROP_KILL_DEAD_CODE);
+ return inserted;
+}
- if (update_life_p)
- sbitmap_free (blocks);
- return purged;
+/* 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);
+
+ new_bb->il.rtl->footer = bb->il.rtl->footer;
+ bb->il.rtl->footer = 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
+ && (ret = try_redirect_by_replacing_jump (e, dest, true)))
+ {
+ df_set_bb_dirty (src);
+ return ret;
+ }
+
+ if (e->src == ENTRY_BLOCK_PTR
+ && (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->il.rtl->header)
+ {
+ next = BB_HEAD (bb);
+ if (prev)
+ NEXT_INSN (prev) = bb->il.rtl->header;
+ else
+ set_first_insn (bb->il.rtl->header);
+ PREV_INSN (bb->il.rtl->header) = prev;
+ insn = bb->il.rtl->header;
+ while (NEXT_INSN (insn))
+ insn = NEXT_INSN (insn);
+ NEXT_INSN (insn) = next;
+ PREV_INSN (next) = insn;
+ }
+ next = NEXT_INSN (BB_END (bb));
+ if (bb->il.rtl->footer)
+ {
+ insn = bb->il.rtl->footer;
+ while (insn)
+ {
+ if (BARRIER_P (insn))
+ {
+ if (PREV_INSN (insn))
+ NEXT_INSN (PREV_INSN (insn)) = NEXT_INSN (insn);
+ else
+ bb->il.rtl->footer = 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->il.rtl->footer)
+ {
+ insn = BB_END (bb);
+ NEXT_INSN (insn) = bb->il.rtl->footer;
+ PREV_INSN (bb->il.rtl->footer) = 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)
+ to = &bb->next_bb->il.rtl->header;
+ 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;
+
+ /* 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 && b != EXIT_BLOCK_PTR
+ /* 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;
+
+ 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 and the edge is the only place in RTL which holds
+ some unique locus, emit a nop with that locus in between. */
+ if (!optimize && EDGE_SUCC (a, 0)->goto_locus)
+ {
+ rtx insn = BB_END (a), end = PREV_INSN (BB_HEAD (a));
+ int goto_locus = EDGE_SUCC (a, 0)->goto_locus;
+
+ while (insn != end && (!INSN_P (insn) || INSN_LOCATOR (insn) == 0))
+ insn = PREV_INSN (insn);
+ if (insn != end && locator_eq (INSN_LOCATOR (insn), goto_locus))
+ goto_locus = 0;
+ else
+ {
+ insn = BB_HEAD (b);
+ end = NEXT_INSN (BB_END (b));
+ while (insn != end && !INSN_P (insn))
+ insn = NEXT_INSN (insn);
+ if (insn != end && INSN_LOCATOR (insn) != 0
+ && locator_eq (INSN_LOCATOR (insn), goto_locus))
+ goto_locus = 0;
+ }
+ if (goto_locus)
+ {
+ BB_END (a) = emit_insn_after_noloc (gen_nop (), BB_END (a), a);
+ INSN_LOCATOR (BB_END (a)) = goto_locus;
+ }
+ }
+
+ /* Possible line number notes should appear in between. */
+ if (b->il.rtl->header)
+ {
+ rtx first = BB_END (a), last;
+
+ last = emit_insn_after_noloc (b->il.rtl->header, BB_END (a), a);
+ delete_insn_chain (NEXT_INSN (first), last, false);
+ b->il.rtl->header = NULL;
+ }
+
+ /* In the case basic blocks are not adjacent, move them around. */
+ if (NEXT_INSN (BB_END (a)) != BB_HEAD (b))
+ {
+ rtx first = unlink_insn_chain (BB_HEAD (b), BB_END (b));
+
+ emit_insn_after_noloc (first, BB_END (a), a);
+ /* Skip possible DELETED_LABEL insn. */
+ if (!NOTE_INSN_BASIC_BLOCK_P (first))
+ first = NEXT_INSN (first);
+ gcc_assert (NOTE_INSN_BASIC_BLOCK_P (first));
+ BB_HEAD (b) = NULL;
+
+ /* emit_insn_after_noloc doesn't call df_insn_change_bb.
+ We need to explicitly call. */
+ update_bb_for_insn_chain (NEXT_INSN (first),
+ BB_END (b),
+ a);
+
+ delete_insn (first);
+ }
+ /* Otherwise just re-associate the instructions. */
+ else
+ {
+ rtx insn;
+
+ update_bb_for_insn_chain (BB_HEAD (b), BB_END (b), a);
+
+ insn = BB_HEAD (b);
+ /* 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) = NULL;
+ BB_END (a) = BB_END (b);
+ delete_insn (insn);
+ }
+
+ df_bb_delete (b->index);
+
+ /* Possible tablejumps and barriers should appear after the block. */
+ if (b->il.rtl->footer)
+ {
+ if (!a->il.rtl->footer)
+ a->il.rtl->footer = b->il.rtl->footer;
+ else
+ {
+ rtx last = a->il.rtl->footer;
+
+ while (NEXT_INSN (last))
+ last = NEXT_INSN (last);
+ NEXT_INSN (last) = b->il.rtl->footer;
+ PREV_INSN (b->il.rtl->footer) = last;
+ }
+ b->il.rtl->footer = NULL;
+ }
+
+ /* If B was a forwarder block, propagate the locus on the edge. */
+ if (forwarder_p && !EDGE_SUCC (b, 0)->goto_locus)
+ 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
+ ? NEXT_INSN (BB_END (e->src)) : get_insns (),
+ NULL_RTX, e->src);
+
+ if (e->dest == EXIT_BLOCK_PTR)
+ 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 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;
+ bool check_last_block = false;
+
+ if (n_basic_blocks == NUM_FIXED_BLOCKS)
+ return 0;
+
+ if (! blocks)
+ check_last_block = true;
+ else
+ check_last_block = TEST_BIT (blocks, EXIT_BLOCK_PTR->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->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);
+ 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 (i);
+ rtx insn;
+ rtx prev_insn;
+
+ if (!bb)
+ continue;
+
+ if (blocks && !TEST_BIT (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);
+ 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, 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.rtl);
+ bb->il.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)
+ return false;
+
+ if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH))
+ return false;
+
+ if (find_reg_note (insn, REG_CROSSING_JUMP, NULL_RTX)
+ || 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;
+}
+
+/* Implementation of CFG manipulation for linearized RTL. */
+struct cfg_hooks rtl_cfg_hooks = {
+ "rtl",
+ rtl_verify_flow_info,
+ rtl_dump_bb,
+ 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,
+ NULL, /* can_duplicate_block_p */
+ NULL, /* duplicate_block */
+ 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 */
+};
+
+/* 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. */
+
+/* We do not want to declare these functions in a header file, since they
+ should only be used through the cfghooks interface, and we do not want to
+ move them here since it would require also moving quite a lot of related
+ code. They are in cfglayout.c. */
+extern bool cfg_layout_can_duplicate_bb_p (const_basic_block);
+extern basic_block cfg_layout_duplicate_bb (basic_block);
+
+struct cfg_hooks cfg_layout_rtl_cfg_hooks = {
+ "cfglayout mode",
+ rtl_verify_flow_info_1,
+ rtl_dump_bb,
+ 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 */
+};
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