/* Control flow graph manipulation code for GNU compiler.
Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
- 1999, 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
+ 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
+ 2011, 2012 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, 51 Franklin Street, Fifth Floor, Boston, MA
-02110-1301, 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.
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
#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"
#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 (rtx);
-static int can_delete_label_p (rtx);
-static void commit_one_edge_insertion (edge, int);
+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 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);
+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
so that we may simply delete it. */
static int
-can_delete_note_p (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);
+ 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 (rtx label)
+can_delete_label_p (const_rtx label)
{
return (!LABEL_PRESERVE_P (label)
/* User declared labels must be preserved. */
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_KIND (insn) = NOTE_INSN_DELETED_LABEL;
NOTE_DELETED_LABEL_NAME (insn) = name;
}
/* If deleting a jump, decrement the use count of the label. Deleting
the label itself should happen in the normal course of block merging. */
- if (JUMP_P (insn)
- && JUMP_LABEL (insn)
- && LABEL_P (JUMP_LABEL (insn)))
- LABEL_NUSES (JUMP_LABEL (insn))--;
-
- /* Also if deleting an insn that references a label. */
- else
+ if (JUMP_P (insn))
{
- while ((note = find_reg_note (insn, REG_LABEL, NULL_RTX)) != NULL_RTX
+ 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))--;
}
}
- if (JUMP_P (insn)
- && (GET_CODE (PATTERN (insn)) == ADDR_VEC
- || GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC))
+ /* Also if deleting any insn that references a label as an operand. */
+ while ((note = find_reg_note (insn, REG_LABEL_OPERAND, NULL_RTX)) != NULL_RTX
+ && LABEL_P (XEXP (note, 0)))
+ {
+ LABEL_NUSES (XEXP (note, 0))--;
+ remove_note (insn, note);
+ }
+
+ if (JUMP_TABLE_DATA_P (insn))
{
rtx pat = PATTERN (insn);
int diff_vec_p = GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC;
}
/* Like delete_insn but also purge dead edges from BB. */
+
rtx
delete_insn_and_edges (rtx insn)
{
}
/* 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 (rtx start, rtx finish)
+delete_insn_chain (rtx start, rtx finish, bool clear_bb)
{
rtx next;
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 (rtx first, rtx last)
-{
- bool purge = false;
-
- if (INSN_P (last)
- && BLOCK_FOR_INSN (last)
- && BB_END (BLOCK_FOR_INSN (last)) == 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
bb->flags = BB_NEW | BB_RTL;
link_block (bb, after);
SET_BASIC_BLOCK (bb->index, bb);
+ df_bb_refs_record (bb->index, false);
update_bb_for_insn (bb);
BB_SET_PARTITION (bb, BB_UNPARTITIONED);
}
/* Create new basic block consisting of instructions in between HEAD and END
- and place it to the BB chain after block AFTER. END can be NULL in to
- create new empty basic block before HEAD. Both END and HEAD can be NULL to
- create basic block at the end of INSN chain. */
+ and place it to the BB chain after block AFTER. END can be NULL to
+ create a new empty basic block before HEAD. Both END and HEAD can be
+ NULL to create basic block at the end of INSN chain. */
static basic_block
rtl_create_basic_block (void *headp, void *endp, basic_block after)
{
- rtx head = headp, end = endp;
+ rtx head = (rtx) headp, end = (rtx) endp;
basic_block bb;
/* Grow the basic block array if needed. */
if ((size_t) last_basic_block >= VEC_length (basic_block, basic_block_info))
{
- size_t old_size = VEC_length (basic_block, basic_block_info);
size_t new_size = last_basic_block + (last_basic_block + 3) / 4;
- basic_block *p;
- VEC_safe_grow (basic_block, gc, basic_block_info, new_size);
- p = VEC_address (basic_block, basic_block_info);
- memset (&p[old_size], 0, sizeof (basic_block) * (new_size - old_size));
+ VEC_safe_grow_cleared (basic_block, gc, basic_block_info, new_size);
}
n_basic_blocks++;
static void
rtl_delete_block (basic_block b)
{
- 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. */
insn = BB_HEAD (b);
- if (LABEL_P (insn))
- maybe_remove_eh_handler (insn);
-
- /* Include any jump table following the basic block. */
- end = BB_END (b);
- if (tablejump_p (end, NULL, &tmp))
- end = tmp;
- /* Include any barriers that may follow the basic block. */
- tmp = next_nonnote_insn (end);
- while (tmp && BARRIER_P (tmp))
- {
- end = tmp;
- tmp = next_nonnote_insn (end);
- }
+ end = get_last_bb_insn (b);
/* Selectively delete the entire chain. */
BB_HEAD (b) = NULL;
- delete_insn_chain (insn, end);
+ delete_insn_chain (insn, end, true);
+
+
+ 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. */
return 0;
}
-struct tree_opt_pass pass_free_cfg =
+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;
+}
+
+struct rtl_opt_pass pass_free_cfg =
{
- NULL, /* name */
+ {
+ RTL_PASS,
+ "*free_cfg", /* name */
NULL, /* gate */
- free_bb_for_insn, /* execute */
+ rest_of_pass_free_cfg, /* execute */
NULL, /* sub */
NULL, /* next */
0, /* static_pass_number */
- 0, /* tv_id */
+ TV_NONE, /* tv_id */
0, /* properties_required */
0, /* properties_provided */
PROP_cfg, /* properties_destroyed */
0, /* todo_flags_start */
0, /* todo_flags_finish */
- 0 /* letter */
+ }
};
/* 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 ?
+ return (n_basic_blocks > NUM_FIXED_BLOCKS ?
BB_HEAD (ENTRY_BLOCK_PTR->next_bb) : get_insns ());
}
-/* Update insns block within BB. */
+/* Emit INSN at the entry point of the function, ensuring that it is only
+ executed once per function. */
+void
+emit_insn_at_entry (rtx insn)
+{
+ edge_iterator ei = ei_start (ENTRY_BLOCK_PTR->succs);
+ edge e = ei_safe_edge (ei);
+ gcc_assert (e->flags & EDGE_FALLTHRU);
+
+ insert_insn_on_edge (insn, e);
+ commit_edge_insertions ();
+}
+
+/* Update BLOCK_FOR_INSN of insns between BEGIN and END
+ (or BARRIER if found) and notify df of the bb change.
+ The insn chain range is inclusive
+ (i.e. both BEGIN and END will be updated. */
+
+static void
+update_bb_for_insn_chain (rtx begin, rtx end, basic_block bb)
+{
+ rtx insn;
+
+ end = NEXT_INSN (end);
+ for (insn = begin; insn != end; insn = NEXT_INSN (insn))
+ if (!BARRIER_P (insn))
+ df_insn_change_bb (insn, bb);
+}
+
+/* Update BLOCK_FOR_INSN of insns in BB to BB,
+ and notify df of the change. */
void
update_bb_for_insn (basic_block bb)
{
+ update_bb_for_insn_chain (BB_HEAD (bb), BB_END (bb), bb);
+}
+
+\f
+/* Return the NOTE_INSN_BASIC_BLOCK of BB. */
+rtx
+bb_note (basic_block bb)
+{
+ rtx note;
+
+ note = BB_HEAD (bb);
+ if (LABEL_P (note))
+ note = NEXT_INSN (note);
+
+ gcc_assert (NOTE_INSN_BASIC_BLOCK_P (note));
+ return note;
+}
+
+/* Return the INSN immediately following the NOTE_INSN_BASIC_BLOCK
+ note associated with the BLOCK. */
+
+static rtx
+first_insn_after_basic_block_note (basic_block block)
+{
rtx insn;
- for (insn = BB_HEAD (bb); ; insn = NEXT_INSN (insn))
- {
- if (!BARRIER_P (insn))
- set_block_for_insn (insn, bb);
- if (insn == BB_END (bb))
- break;
- }
+ /* 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);
}
-\f
+
/* Creates a new basic block just after basic block B by splitting
everything after specified instruction I. */
rtl_split_block (basic_block bb, void *insnp)
{
basic_block new_bb;
- rtx insn = insnp;
+ rtx insn = (rtx) insnp;
edge e;
edge_iterator ei;
insn = first_insn_after_basic_block_note (bb);
if (insn)
- insn = PREV_INSN (insn);
+ {
+ rtx next = insn;
+
+ insn = PREV_INSN (insn);
+
+ /* If the block contains only debug insns, insn would have
+ been NULL in a non-debug compilation, and then we'd end
+ up emitting a DELETED note. For -fcompare-debug
+ stability, emit the note too. */
+ if (insn != BB_END (bb)
+ && DEBUG_INSN_P (next)
+ && DEBUG_INSN_P (BB_END (bb)))
+ {
+ while (next != BB_END (bb) && DEBUG_INSN_P (next))
+ next = NEXT_INSN (next);
+
+ if (next == BB_END (bb))
+ emit_note_after (NOTE_INSN_DELETED, next);
+ }
+ }
else
insn = get_last_insn ();
}
FOR_EACH_EDGE (e, ei, new_bb->succs)
e->src = new_bb;
- if (bb->il.rtl->global_live_at_start)
- {
- new_bb->il.rtl->global_live_at_start = ALLOC_REG_SET (®_obstack);
- new_bb->il.rtl->global_live_at_end = ALLOC_REG_SET (®_obstack);
- COPY_REG_SET (new_bb->il.rtl->global_live_at_end, bb->il.rtl->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->il.rtl->global_live_at_start, bb->il.rtl->global_live_at_end);
- propagate_block (new_bb, new_bb->il.rtl->global_live_at_start, NULL, NULL, 0);
- COPY_REG_SET (bb->il.rtl->global_live_at_end,
- new_bb->il.rtl->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;
- }
-#endif
- }
-
+ /* The new block starts off being dirty. */
+ df_set_bb_dirty (bb);
return new_bb;
}
{
rtx b_head = BB_HEAD (b), b_end = BB_END (b), a_end = BB_END (a);
rtx del_first = NULL_RTX, del_last = NULL_RTX;
+ rtx b_debug_start = b_end, b_debug_end = b_end;
+ bool forwarder_p = (b->flags & BB_FORWARDER_BLOCK) != 0;
int b_empty = 0;
+ if (dump_file)
+ fprintf (dump_file, "Merging block %d into block %d...\n", b->index,
+ a->index);
+
+ while (DEBUG_INSN_P (b_end))
+ b_end = PREV_INSN (b_debug_start = b_end);
+
/* If there was a CODE_LABEL beginning B, delete it. */
if (LABEL_P (b_head))
{
- /* This might have been an EH label that no longer has incoming
- EH edges. Update data structures to match. */
- maybe_remove_eh_handler (b_head);
-
/* Detect basic blocks with nothing but a label. This can happen
in particular at the end of a function. */
if (b_head == b_end)
for (prev = PREV_INSN (a_end); ; prev = PREV_INSN (prev))
if (!NOTE_P (prev)
- || NOTE_LINE_NUMBER (prev) == NOTE_INSN_BASIC_BLOCK
+ || NOTE_INSN_BASIC_BLOCK_P (prev)
|| prev == BB_HEAD (a))
break;
/* Delete everything marked above as well as crap that might be
hanging out between the two blocks. */
BB_HEAD (b) = NULL;
- delete_insn_chain (del_first, del_last);
+ delete_insn_chain (del_first, del_last, true);
/* Reassociate the insns of B with A. */
if (!b_empty)
{
- rtx x;
-
- for (x = a_end; x != b_end; x = NEXT_INSN (x))
- set_block_for_insn (x, a);
+ update_bb_for_insn_chain (a_end, b_debug_end, a);
- set_block_for_insn (b_end, a);
-
- a_end = b_end;
+ 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;
}
+ df_bb_delete (b->index);
BB_END (a) = a_end;
- a->il.rtl->global_live_at_end = b->il.rtl->global_live_at_end;
+
+ /* 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);
}
+
/* Return true when block A and B can be merged. */
+
static bool
-rtl_can_merge_blocks (basic_block a,basic_block b)
+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
+ 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))
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
+ 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;
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
{
rtx insn = src->il.rtl->footer;
- delete_insn_chain (kill_from, BB_END (src));
+ delete_insn_chain (kill_from, BB_END (src), false);
/* Remove barriers but keep jumptables. */
while (insn)
}
}
else
- delete_insn_chain (kill_from, PREV_INSN (BB_HEAD (target)));
+ delete_insn_chain (kill_from, PREV_INSN (BB_HEAD (target)),
+ false);
}
/* If this already is simplejump, redirect it. */
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))
which originally were or were created before jump table are
inside the basic block. */
rtx new_insn = BB_END (src);
- rtx tmp;
- for (tmp = NEXT_INSN (BB_END (src)); tmp != barrier;
- tmp = NEXT_INSN (tmp))
- set_block_for_insn (tmp, 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);
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 (NOTE_P (BB_END (e->src))
- && NOTE_LINE_NUMBER (BB_END (e->src)) >= 0)
- delete_insn (BB_END (e->src));
-
if (e->dest != target)
redirect_edge_succ (e, target);
-
return e;
}
-/* Redirect edge representing branch of (un)conditional jump or tablejump,
- NULL on failure */
-static edge
-redirect_branch_edge (edge e, basic_block target)
+/* Subroutine of redirect_branch_edge that tries to patch the jump
+ instruction INSN so that it reaches block NEW. Do this
+ only when it originally reached block OLD. Return true if this
+ worked or the original target wasn't OLD, return false if redirection
+ doesn't work. */
+
+static bool
+patch_jump_insn (rtx insn, rtx old_label, basic_block new_bb)
{
rtx tmp;
- 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))
- return NULL;
-
/* 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)
- return NULL;
+ if (new_bb == EXIT_BLOCK_PTR)
+ return false;
if (GET_CODE (PATTERN (tmp)) == ADDR_VEC)
vec = XVEC (PATTERN (tmp), 0);
else
++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
if (computed_jump_p (insn)
/* A return instruction can't be redirected. */
|| returnjump_p (insn))
- return NULL;
+ return false;
- /* 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 (target), 0))
+ if (!currently_expanding_to_rtl || JUMP_LABEL (insn) == old_label)
{
- gcc_assert (target == EXIT_BLOCK_PTR);
- return NULL;
+ /* 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 (!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",
if (e->dest != target)
e = redirect_edge_succ_nodup (e, target);
+
return e;
}
if ((ret = try_redirect_by_replacing_jump (e, target, false)) != NULL)
{
- src->flags |= BB_DIRTY;
+ df_set_bb_dirty (src);
return ret;
}
if (!ret)
return NULL;
- src->flags |= BB_DIRTY;
+ df_set_bb_dirty (src);
return ret;
}
/* Like force_nonfallthru below, but additionally performs redirection
- Used by redirect_edge_and_branch_force. */
+ Used by redirect_edge_and_branch_force. JUMP_LABEL is used only
+ when redirecting to the EXIT_BLOCK, it is either ret_rtx or
+ simple_return_rtx, indicating which kind of returnjump to create.
+ It should be NULL otherwise. */
-static basic_block
-force_nonfallthru_and_redirect (edge e, basic_block target)
+basic_block
+force_nonfallthru_and_redirect (edge e, basic_block target, rtx jump_label)
{
basic_block jump_block, new_bb = NULL, src = e->src;
rtx note;
edge new_edge;
int abnormal_edge_flags = 0;
+ bool asm_goto_edge = false;
+ int loc;
/* In the case the last instruction is conditional jump to the next
instruction, first redirect the jump itself and then continue
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)
{
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;
else
ei_next (&ei);
}
-
+
gcc_assert (found);
-
+
VEC_safe_push (edge, gc, bb->succs, e);
make_single_succ_edge (ENTRY_BLOCK_PTR, bb, EDGE_FALLTHRU);
}
}
- if (EDGE_COUNT (e->src->succs) >= 2 || abnormal_edge_flags)
+ /* If e->src ends with asm goto, see if any of the ASM_OPERANDS_LABELs
+ don't point to the target or fallthru label. */
+ if (JUMP_P (BB_END (e->src))
+ && target != EXIT_BLOCK_PTR
+ && (e->flags & EDGE_FALLTHRU)
+ && (note = extract_asm_operands (PATTERN (BB_END (e->src)))))
+ {
+ int i, n = ASM_OPERANDS_LABEL_LENGTH (note);
+
+ for (i = 0; i < n; ++i)
+ {
+ if (XEXP (ASM_OPERANDS_LABEL (note, i), 0) == BB_HEAD (e->dest))
+ XEXP (ASM_OPERANDS_LABEL (note, i), 0) = block_label (target);
+ if (XEXP (ASM_OPERANDS_LABEL (note, i), 0) == BB_HEAD (target))
+ asm_goto_edge = true;
+ }
+ }
+
+ if (EDGE_COUNT (e->src->succs) >= 2 || abnormal_edge_flags || asm_goto_edge)
{
+ gcov_type count = e->count;
+ int probability = e->probability;
/* Create the new structures. */
/* If the old block ended with a tablejump, skip its table
note = NEXT_INSN (note);
jump_block = create_basic_block (note, NULL, e->src);
- jump_block->count = e->count;
+ jump_block->count = count;
jump_block->frequency = EDGE_FREQUENCY (e);
jump_block->loop_depth = target->loop_depth;
- if (target->il.rtl->global_live_at_start)
- {
- jump_block->il.rtl->global_live_at_start = ALLOC_REG_SET (®_obstack);
- jump_block->il.rtl->global_live_at_end = ALLOC_REG_SET (®_obstack);
- COPY_REG_SET (jump_block->il.rtl->global_live_at_start,
- target->il.rtl->global_live_at_start);
- COPY_REG_SET (jump_block->il.rtl->global_live_at_end,
- target->il.rtl->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.have_named_sections
+ && 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))
- REG_NOTES (BB_END (jump_block)) = gen_rtx_EXPR_LIST (REG_CROSSING_JUMP,
- NULL_RTX,
- REG_NOTES
- (BB_END
- (jump_block)));
-
+ 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);
- new_edge->probability = e->probability;
- new_edge->count = e->count;
+ new_edge->probability = probability;
+ new_edge->count = count;
/* Redirect old edge. */
redirect_edge_pred (e, jump_block);
e->probability = REG_BR_PROB_BASE;
+ /* If asm goto has any label refs to target's label,
+ add also edge from asm goto bb to target. */
+ if (asm_goto_edge)
+ {
+ new_edge->probability /= 2;
+ new_edge->count /= 2;
+ jump_block->count /= 2;
+ jump_block->frequency /= 2;
+ new_edge = make_edge (new_edge->src, target,
+ e->flags & ~EDGE_FALLTHRU);
+ new_edge->probability = probability - probability / 2;
+ new_edge->count = count - count / 2;
+ }
+
new_bb = jump_block;
}
else
jump_block = e->src;
+ 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 (jump_label == ret_rtx)
+ {
#ifdef HAVE_return
- emit_jump_insn_after_noloc (gen_return (), BB_END (jump_block));
+ emit_jump_insn_after_setloc (gen_return (), BB_END (jump_block), loc);
+#else
+ gcc_unreachable ();
+#endif
+ }
+ else
+ {
+ gcc_assert (jump_label == simple_return_rtx);
+#ifdef HAVE_simple_return
+ emit_jump_insn_after_setloc (gen_simple_return (),
+ BB_END (jump_block), loc);
#else
- gcc_unreachable ();
+ gcc_unreachable ();
#endif
+ }
+ set_return_jump_label (BB_END (jump_block));
}
else
{
rtx label = block_label (target);
- emit_jump_insn_after_noloc (gen_jump (label), BB_END (jump_block));
+ emit_jump_insn_after_setloc (gen_jump (label), BB_END (jump_block), loc);
JUMP_LABEL (BB_END (jump_block)) = label;
LABEL_NUSES (label)++;
}
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 (edge e)
+static basic_block
+rtl_force_nonfallthru (edge e)
{
- return force_nonfallthru_and_redirect (e, e->dest);
+ return force_nonfallthru_and_redirect (e, e->dest, NULL_RTX);
}
/* Redirect edge even at the expense of creating new jump insn or
/* In case the edge redirection failed, try to force it to be non-fallthru
and redirect newly created simplejump. */
- e->src->flags |= BB_DIRTY;
- return force_nonfallthru_and_redirect (e, target);
+ df_set_bb_dirty (e->src);
+ return force_nonfallthru_and_redirect (e, target, NULL_RTX);
}
/* The given edge should potentially be a fallthru edge. If that is in
#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 (NOTE_P (q) && NOTE_LINE_NUMBER (q) >= 0)
- q = PREV_INSN (q);
}
/* Selectively unlink the sequence. */
if (q != PREV_INSN (BB_HEAD (c)))
- delete_insn_chain (NEXT_INSN (q), PREV_INSN (BB_HEAD (c)));
+ delete_insn_chain (NEXT_INSN (q), PREV_INSN (BB_HEAD (c)), false);
e->flags |= EDGE_FALLTHRU;
}
Avoid existence of fallthru predecessors. */
if ((edge_in->flags & EDGE_FALLTHRU) == 0)
{
- edge e;
- edge_iterator ei;
-
- FOR_EACH_EDGE (e, ei, edge_in->dest->preds)
- if (e->flags & EDGE_FALLTHRU)
- break;
+ edge e = find_fallthru_edge (edge_in->dest->preds);
if (e)
force_nonfallthru (e);
before = NULL_RTX;
/* If this is a fall through edge to the exit block, the blocks might be
- not adjacent, and the right place is the after the source. */
- if (edge_in->flags & EDGE_FALLTHRU && edge_in->dest == EXIT_BLOCK_PTR)
+ not adjacent, and the right place is after the source. */
+ if ((edge_in->flags & EDGE_FALLTHRU) && edge_in->dest == EXIT_BLOCK_PTR)
{
before = NEXT_INSN (BB_END (edge_in->src));
bb = create_basic_block (before, NULL, edge_in->src);
BB_COPY_PARTITION (bb, edge_in->dest);
}
- /* ??? This info is likely going to be out of date very soon. */
- if (edge_in->dest->il.rtl->global_live_at_start)
- {
- bb->il.rtl->global_live_at_start = ALLOC_REG_SET (®_obstack);
- bb->il.rtl->global_live_at_end = ALLOC_REG_SET (®_obstack);
- COPY_REG_SET (bb->il.rtl->global_live_at_start,
- edge_in->dest->il.rtl->global_live_at_start);
- COPY_REG_SET (bb->il.rtl->global_live_at_end,
- edge_in->dest->il.rtl->global_live_at_start);
- }
-
make_single_succ_edge (bb, edge_in->dest, EDGE_FALLTHRU);
/* For non-fallthru edges, we must adjust the predecessor's
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;
}
/* Update the CFG for the instructions queued on edge E. */
-static void
-commit_one_edge_insertion (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.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)
- && single_pred_p (e->dest)
- && e->src != ENTRY_BLOCK_PTR
- && CALL_P (BB_END (e->src)))
+ /* 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 (BB_END (e->src));
-
- after = BB_HEAD (e->dest);
- /* 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;
- }
- if (!before && !after)
- {
- /* Figure out where to put these things. If the destination has
- one predecessor, insert there. Except for the exit block. */
- if (single_pred_p (e->dest) && 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 (bb);
- if (LABEL_P (tmp))
- tmp = NEXT_INSN (tmp);
- if (NOTE_INSN_BASIC_BLOCK_P (tmp))
- tmp = NEXT_INSN (tmp);
- if (tmp == BB_HEAD (bb))
- before = tmp;
- else if (tmp)
- after = PREV_INSN (tmp);
- else
- after = get_last_insn ();
- }
- /* If the source has one successor and the edge is not abnormal,
- insert there. Except for the entry block. */
- else if ((e->flags & EDGE_ABNORMAL) == 0
- && single_succ_p (e->src)
- && e->src != ENTRY_BLOCK_PTR)
- {
- bb = e->src;
+ /* 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 ();
+ }
- /* 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.
+ /* 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)
+ {
+ bb = e->src;
- We know this block has a single successor, so we can just emit
- the queued insns before the jump. */
- if (JUMP_P (BB_END (bb)))
- before = BB_END (bb);
- else
- {
- /* We'd better be fallthru, or we've lost track of
- what's what. */
- gcc_assert (e->flags & EDGE_FALLTHRU);
+ /* 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 (bb);
- }
- }
- /* 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 (bb);
+ /* We'd better be fallthru, or we've lost track of what's what. */
+ gcc_assert (e->flags & EDGE_FALLTHRU);
- if (flag_reorder_blocks_and_partition
- && targetm.have_named_sections
- && e->src != ENTRY_BLOCK_PTR
- && BB_PARTITION (e->src) == BB_COLD_PARTITION
- && !(e->flags & EDGE_CROSSING))
- {
- rtx bb_note, cur_insn;
-
- bb_note = NULL_RTX;
- for (cur_insn = BB_HEAD (bb); cur_insn != NEXT_INSN (BB_END (bb));
- cur_insn = NEXT_INSN (cur_insn))
- if (NOTE_P (cur_insn)
- && NOTE_LINE_NUMBER (cur_insn) == NOTE_INSN_BASIC_BLOCK)
- {
- bb_note = cur_insn;
- break;
- }
-
- if (JUMP_P (BB_END (bb))
- && !any_condjump_p (BB_END (bb))
- && (single_succ_edge (bb)->flags & EDGE_CROSSING))
- REG_NOTES (BB_END (bb)) = gen_rtx_EXPR_LIST
- (REG_CROSSING_JUMP, NULL_RTX, REG_NOTES (BB_END (bb)));
- }
+ 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_noloc (insns, before);
+ emit_insn_before_noloc (insns, before, bb);
last = prev_nonnote_insn (before);
}
else
- last = emit_insn_after_noloc (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 = single_succ_edge (bb);
gcc_assert (e->dest == EXIT_BLOCK_PTR
}
else
gcc_assert (!JUMP_P (last));
-
- /* Mark the basic block for find_many_sub_basic_blocks. */
- bb->aux = &bb->aux;
}
/* Update the CFG for all queued instructions. */
commit_edge_insertions (void)
{
basic_block bb;
- sbitmap blocks;
- bool changed = false;
#ifdef ENABLE_CHECKING
verify_flow_info ();
FOR_EACH_EDGE (e, ei, bb->succs)
if (e->insns.r)
- {
- changed = true;
- commit_one_edge_insertion (e, false);
- }
+ 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. */
- gcc_assert (bb->aux == &bb->aux);
- 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 (void)
-{
- 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;
- edge_iterator ei;
-
- FOR_EACH_EDGE (e, ei, bb->succs)
- if (e->insns.r)
- {
- 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. */
- gcc_assert (bb->aux == &bb->aux);
- bb->aux = NULL;
- }
- find_many_sub_basic_blocks (blocks);
- sbitmap_free (blocks);
-}
-\f
-/* Print out RTL-specific basic block information (live information
- at start and end). */
+/* Print out RTL-specific basic block information (live information
+ at start and end). */
static void
-rtl_dump_bb (basic_block bb, FILE *outf, int indent)
+rtl_dump_bb (basic_block bb, FILE *outf, int indent, int flags ATTRIBUTE_UNUSED)
{
rtx insn;
rtx last;
char *s_indent;
- s_indent = alloca ((size_t) indent + 1);
+ s_indent = (char *) alloca ((size_t) indent + 1);
memset (s_indent, ' ', (size_t) indent);
s_indent[indent] = '\0';
- fprintf (outf, ";;%s Registers live at start: ", s_indent);
- dump_regset (bb->il.rtl->global_live_at_start, outf);
- putc ('\n', outf);
+ if (df)
+ {
+ df_dump_top (bb, outf);
+ putc ('\n', outf);
+ }
+
+ if (bb->index != ENTRY_BLOCK && bb->index != EXIT_BLOCK)
+ for (insn = BB_HEAD (bb), last = NEXT_INSN (BB_END (bb)); insn != last;
+ insn = NEXT_INSN (insn))
+ print_rtl_single (outf, insn);
- for (insn = BB_HEAD (bb), last = NEXT_INSN (BB_END (bb)); insn != last;
- insn = NEXT_INSN (insn))
- print_rtl_single (outf, insn);
+ if (df)
+ {
+ df_dump_bottom (bb, outf);
+ putc ('\n', outf);
+ }
- fprintf (outf, ";;%s Registers live at end: ", s_indent);
- dump_regset (bb->il.rtl->global_live_at_end, outf);
- putc ('\n', outf);
}
\f
/* Like print_rtl, but also print out live information for the start of each
basic block. */
void
-print_rtl_with_bb (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
basic_block bb;
+ if (df)
+ df_dump_start (outf);
+
FOR_EACH_BB_REVERSE (bb)
{
rtx x;
{
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->il.rtl->global_live_at_start, outf);
- putc ('\n', outf);
- }
+ bb = start[INSN_UID (tmp_rtx)];
+ if (bb != NULL)
+ dump_bb_info (bb, true, false, dump_flags, ";; ", outf);
if (in_bb_p[INSN_UID (tmp_rtx)] == NOT_IN_BB
&& !NOTE_P (tmp_rtx)
did_output = print_rtl_single (outf, tmp_rtx);
- if ((bb = end[INSN_UID (tmp_rtx)]) != NULL)
- {
- fprintf (outf, ";; End of basic block %d, registers live:\n",
- bb->index);
- dump_regset (bb->il.rtl->global_live_at_end, outf);
- putc ('\n', outf);
- }
-
+ bb = end[INSN_UID (tmp_rtx)];
+ if (bb != NULL)
+ dump_bb_info (bb, false, true, dump_flags, ";; ", 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));
}
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 and RTL consistency common for both underlying RTL and
cfglayout RTL.
Currently it does following checks:
- - test head/end pointers
- overlapping of basic blocks
+ - insns with wrong BLOCK_FOR_INSN pointers
- headers of basic blocks (the NOTE_INSN_BASIC_BLOCK note)
- tails of basic blocks (ensure that boundary is necessary)
- scans body of the basic block for JUMP_INSN, CODE_LABEL
and NOTE_INSN_BASIC_BLOCK
- verify that no fall_thru edge crosses hot/cold partition boundaries
+ - verify that there are no pending RTL branch predictions
In future it can be extended check a lot of other stuff as well
(reachability of basic blocks, life information, etc. etc.). */
static int
rtl_verify_flow_info_1 (void)
{
- const int max_uid = get_max_uid ();
- rtx last_head = get_last_insn ();
- basic_block *bb_info;
rtx x;
int err = 0;
basic_block bb;
- bb_info = XCNEWVEC (basic_block, max_uid);
-
+ /* Check the general integrity of the basic blocks. */
FOR_EACH_BB_REVERSE (bb)
{
- rtx head = BB_HEAD (bb);
- rtx end = BB_END (bb);
-
- /* 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;
+ rtx insn;
if (!(bb->flags & BB_RTL))
{
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 and initialize the BB_INFO array
- used by other passes. */
- 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;
- }
+ 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;
+ }
- last_head = x;
+ 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_EDGE (e, ei, bb->succs)
{
+ bool is_crossing;
+
if (e->flags & EDGE_FALLTHRU)
+ n_fallthru++, fallthru = e;
+
+ is_crossing = (BB_PARTITION (e->src) != BB_PARTITION (e->dest)
+ && e->src != ENTRY_BLOCK_PTR
+ && e->dest != EXIT_BLOCK_PTR);
+ if (e->flags & EDGE_CROSSING)
{
- 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))
- {
+ if (!is_crossing)
+ {
+ error ("EDGE_CROSSING incorrectly set across same section");
+ err = 1;
+ }
+ if (e->flags & EDGE_FALLTHRU)
+ {
error ("fallthru edge crosses section boundary (bb %i)",
e->src->index);
err = 1;
}
+ if (e->flags & EDGE_EH)
+ {
+ error ("EH edge crosses section boundary (bb %i)",
+ e->src->index);
+ err = 1;
+ }
+ }
+ else if (is_crossing)
+ {
+ error ("EDGE_CROSSING missing across section boundary");
+ err = 1;
}
if ((e->flags & ~(EDGE_DFS_BACK
| EDGE_CAN_FALLTHRU
| EDGE_IRREDUCIBLE_LOOP
| EDGE_LOOP_EXIT
- | EDGE_CROSSING)) == 0)
+ | EDGE_CROSSING
+ | EDGE_PRESERVE)) == 0)
n_branch++;
if (e->flags & EDGE_ABNORMAL_CALL)
n_abnormal++;
}
- if (n_eh && GET_CODE (PATTERN (BB_END (bb))) != RESX
- && !find_reg_note (BB_END (bb), 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);
err = 1;
}
+ if (n_eh > 1)
+ {
+ error ("too many eh edges %i", bb->index);
+ err = 1;
+ }
if (n_branch
&& (!JUMP_P (BB_END (bb))
|| (n_branch > 1 && (any_uncondjump_p (BB_END (bb))
}
if (n_branch != 1 && any_uncondjump_p (BB_END (bb)))
{
- error ("wrong amount of branch edges after unconditional jump %i", bb->index);
+ error ("wrong number of branch edges after unconditional jump %i",
+ bb->index);
err = 1;
}
if (n_branch != 1 && any_condjump_p (BB_END (bb))
}
/* 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 (bb);
if (LABEL_P (x))
}
/* Clean up. */
- free (bb_info);
return err;
}
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. */
+
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;
- edge_iterator ei;
+ rtx head = BB_HEAD (bb);
+ rtx end = BB_END (bb);
- if (bb->predictions)
+ 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 ("bb prediction set for block %i, but it is not used in RTL land", bb->index);
+ error ("end insn %d for block %d not found in the insn stream",
+ INSN_UID (end), bb->index);
err = 1;
}
- FOR_EACH_EDGE (e, ei, bb->succs)
- if (e->flags & EDGE_FALLTHRU)
- break;
+ /* 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 = BB_END (bb); !insn || !BARRIER_P (insn);
- insn = NEXT_INSN (insn))
- if (!insn
- || (NOTE_P (insn)
- && NOTE_LINE_NUMBER (insn) == NOTE_INSN_BASIC_BLOCK))
+ 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)
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;
case CODE_LABEL:
/* An addr_vec is placed outside any basic block. */
if (NEXT_INSN (x)
- && JUMP_P (NEXT_INSN (x))
- && (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 (JUMP_P (x)
&& returnjump_p (x) && ! condjump_p (x)
- && ! (NEXT_INSN (x) && BARRIER_P (NEXT_INSN (x))))
+ && ! (next_nonnote_insn (x) && BARRIER_P (next_nonnote_insn (x))))
fatal_insn ("return not followed by barrier", x);
if (curr_bb && x == BB_END (curr_bb))
curr_bb = NULL;
bool found;
edge_iterator ei;
+ if (DEBUG_INSN_P (insn) && insn != BB_HEAD (bb))
+ do
+ insn = PREV_INSN (insn);
+ while ((DEBUG_INSN_P (insn) || NOTE_P (insn)) && insn != BB_HEAD (bb));
+
/* If this instruction cannot trap, remove REG_EH_REGION notes. */
if (NONJUMP_INSN_P (insn)
&& (note = find_reg_note (insn, REG_EH_REGION, NULL)))
/* Cleanup abnormal edges caused by exceptions or non-local gotos. */
for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
{
+ bool remove = false;
+
/* There are three types of edges we need to handle correctly here: EH
edges, abnormal call EH edges, and abnormal call non-EH edges. The
latter can appear when nonlocal gotos are used. */
- if (e->flags & EDGE_EH)
+ if (e->flags & EDGE_ABNORMAL_CALL)
{
- if (can_throw_internal (BB_END (bb))
- /* If this is a call edge, verify that this is a call insn. */
- && (! (e->flags & EDGE_ABNORMAL_CALL)
- || CALL_P (BB_END (bb))))
- {
- ei_next (&ei);
- continue;
- }
+ if (!CALL_P (insn))
+ remove = true;
+ else if (can_nonlocal_goto (insn))
+ ;
+ else if ((e->flags & EDGE_EH) && can_throw_internal (insn))
+ ;
+ else if (flag_tm && find_reg_note (insn, REG_TM, NULL))
+ ;
+ else
+ remove = true;
}
- else if (e->flags & EDGE_ABNORMAL_CALL)
+ else if (e->flags & EDGE_EH)
+ remove = !can_throw_internal (insn);
+
+ if (remove)
{
- if (CALL_P (BB_END (bb))
- && (! (note = find_reg_note (insn, REG_EH_REGION, NULL))
- || INTVAL (XEXP (note, 0)) >= 0))
- {
- ei_next (&ei);
- continue;
- }
+ remove_edge (e);
+ df_set_bb_dirty (bb);
+ purged = true;
}
else
- {
- ei_next (&ei);
- continue;
- }
-
- remove_edge (e);
- bb->flags |= BB_DIRTY;
- purged = true;
+ ei_next (&ei);
}
if (JUMP_P (insn))
}
/* We do not need this edge. */
- bb->flags |= BB_DIRTY;
+ df_set_bb_dirty (bb);
purged = true;
remove_edge (e);
}
{
if (!(e->flags & (EDGE_FALLTHRU | EDGE_FAKE)))
{
- bb->flags |= BB_DIRTY;
+ df_set_bb_dirty (bb);
remove_edge (e);
purged = true;
}
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)
+ {
+ edge e;
+ edge_iterator ei;
+
+ /* Look for cases we are interested in - calls or instructions causing
+ exceptions. */
+ FOR_EACH_EDGE (e, ei, bb->succs)
+ if ((e->flags & EDGE_ABNORMAL_CALL)
+ || ((e->flags & (EDGE_ABNORMAL | EDGE_EH))
+ == (EDGE_ABNORMAL | EDGE_EH)))
+ break;
+
+ if (e && !CALL_P (BB_END (bb)) && !can_throw_internal (BB_END (bb)))
+ {
+ rtx insn;
+
+ /* Get past the new insns generated. Allow notes, as the insns
+ may be already deleted. */
+ insn = BB_END (bb);
+ while ((NONJUMP_INSN_P (insn) || NOTE_P (insn))
+ && !can_throw_internal (insn)
+ && insn != BB_HEAD (bb))
+ insn = PREV_INSN (insn);
+
+ if (CALL_P (insn) || can_throw_internal (insn))
+ {
+ rtx stop, next;
+
+ e = find_fallthru_edge (bb->succs);
+
+ stop = NEXT_INSN (BB_END (bb));
+ BB_END (bb) = insn;
+
+ for (insn = NEXT_INSN (insn); insn != stop; insn = next)
+ {
+ next = NEXT_INSN (insn);
+ if (INSN_P (insn))
+ {
+ delete_insn (insn);
+
+ /* Sometimes there's still the return value USE.
+ If it's placed after a trapping call (i.e. that
+ call is the last insn anyway), we have no fallthru
+ edge. Simply delete this use and don't try to insert
+ on the non-existent edge. */
+ if (GET_CODE (PATTERN (insn)) != USE)
+ {
+ /* We're not deleting it, we're moving it. */
+ INSN_DELETED_P (insn) = 0;
+ PREV_INSN (insn) = NULL_RTX;
+ NEXT_INSN (insn) = NULL_RTX;
+
+ insert_insn_on_edge (insn, e);
+ inserted = true;
+ }
+ }
+ else if (!BARRIER_P (insn))
+ set_block_for_insn (insn, NULL);
+ }
+ }
+
+ /* It may be that we don't find any trapping insn. In this
+ case we discovered quite late that the insn that had been
+ marked as can_throw_internal in fact couldn't trap at all.
+ So we should in fact delete the EH edges out of the block. */
+ else
+ purge_dead_edges (bb);
+ }
+ }
+
+ return inserted;
+}
+
/* Same as split_block but update cfg_layout structures. */
static basic_block
cfg_layout_split_block (basic_block bb, void *insnp)
{
- rtx insn = insnp;
+ rtx insn = (rtx) insnp;
basic_block new_bb = rtl_split_block (bb, insn);
new_bb->il.rtl->footer = bb->il.rtl->footer;
return new_bb;
}
-
/* Redirect Edge to DEST. */
static edge
cfg_layout_redirect_edge_and_branch (edge e, basic_block dest)
if (e->src != ENTRY_BLOCK_PTR
&& (ret = try_redirect_by_replacing_jump (e, dest, true)))
{
- src->flags |= BB_DIRTY;
+ df_set_bb_dirty (src);
return ret;
}
fprintf (dump_file, "Redirecting entry edge from bb %i to %i\n",
e->src->index, dest->index);
- e->src->flags |= BB_DIRTY;
+ df_set_bb_dirty (e->src);
redirect_edge_succ (e, dest);
return e;
}
BB_END (src)))
{
edge redirected;
-
+
if (dump_file)
fprintf (dump_file, "Fallthru edge unified with branch "
"%i->%i redirected to %i\n",
e->flags &= ~EDGE_FALLTHRU;
redirected = redirect_branch_edge (e, dest);
gcc_assert (redirected);
- e->flags |= EDGE_FALLTHRU;
- e->src->flags |= BB_DIRTY;
- return e;
+ 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. */
+ of conditional jump, remove it. */
if (EDGE_COUNT (src->succs) == 2)
{
/* Find the edge that is different from E. */
&& onlyjump_p (BB_END (src)))
delete_insn (BB_END (src));
}
- ret = redirect_edge_succ_nodup (e, dest);
if (dump_file)
- fprintf (dump_file, "Fallthru edge %i->%i redirected to %i\n",
+ 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)));
- src->flags |= BB_DIRTY;
+ df_set_bb_dirty (src);
return ret;
}
}
/* 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)
{
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
+ 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;
+ /* If we would end up moving B's instructions, make sure it doesn't fall
+ through into the exit block, since we cannot recover from a fallthrough
+ edge into the exit block occurring in the middle of a function. */
+ if (NEXT_INSN (BB_END (a)) != BB_HEAD (b))
+ {
+ edge e = find_fallthru_edge (b->succs);
+ if (e && e->dest == EXIT_BLOCK_PTR)
+ return false;
+ }
+
/* There must be exactly one edge in between the blocks. */
return (single_succ_p (a)
&& single_succ (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. */
+ /* 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))
- || (reload_completed
+ || ((!optimize || reload_completed)
? simplejump_p (BB_END (a)) : onlyjump_p (BB_END (a)))));
}
static void
cfg_layout_merge_blocks (basic_block a, basic_block b)
{
-#ifdef ENABLE_CHECKING
- gcc_assert (cfg_layout_can_merge_blocks_p (a, b));
-#endif
+ 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)))
{
- /* This might have been an EH label that no longer has incoming
- EH edges. Update data structures to match. */
- maybe_remove_eh_handler (BB_HEAD (b));
-
delete_insn (BB_HEAD (b));
}
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));
- delete_insn_chain (NEXT_INSN (first), last);
+ last = emit_insn_after_noloc (b->il.rtl->header, BB_END (a), a);
+ /* The above might add a BARRIER as BB_END, but as barriers
+ aren't valid parts of a bb, remove_insn doesn't update
+ BB_END if it is a barrier. So adjust BB_END here. */
+ while (BB_END (a) != first && BARRIER_P (BB_END (a)))
+ BB_END (a) = PREV_INSN (BB_END (a));
+ delete_insn_chain (NEXT_INSN (first), last, false);
b->il.rtl->header = NULL;
}
{
rtx first = unlink_insn_chain (BB_HEAD (b), BB_END (b));
- emit_insn_after_noloc (first, BB_END (a));
+ 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. */
{
rtx insn;
- for (insn = BB_HEAD (b);
- insn != NEXT_INSN (BB_END (b));
- insn = NEXT_INSN (insn))
- set_block_for_insn (insn, a);
+ 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))
delete_insn (insn);
}
+ df_bb_delete (b->index);
+
/* Possible tablejumps and barriers should appear after the block. */
if (b->il.rtl->footer)
{
}
b->il.rtl->footer = NULL;
}
- a->il.rtl->global_live_at_end = b->il.rtl->global_live_at_end;
+
+ /* 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);
+ fprintf (dump_file, "Merged blocks %d and %d.\n", a->index, b->index);
}
/* Split edge E. */
? NEXT_INSN (BB_END (e->src)) : get_insns (),
NULL_RTX, e->src);
- /* ??? This info is likely going to be out of date very soon, but we must
- create it to avoid getting an ICE later. */
- if (e->dest->il.rtl->global_live_at_start)
- {
- new_bb->il.rtl->global_live_at_start = ALLOC_REG_SET (®_obstack);
- new_bb->il.rtl->global_live_at_end = ALLOC_REG_SET (®_obstack);
- COPY_REG_SET (new_bb->il.rtl->global_live_at_start,
- e->dest->il.rtl->global_live_at_start);
- COPY_REG_SET (new_bb->il.rtl->global_live_at_end,
- e->dest->il.rtl->global_live_at_start);
- }
-
+ 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);
while (!CALL_P (insn)
&& insn != BB_HEAD (bb)
- && keep_with_call_p (insn))
+ && (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 (basic_block bb)
+rtl_block_ends_with_condjump_p (const_basic_block bb)
{
return any_condjump_p (BB_END (bb));
}
Helper function for rtl_flow_call_edges_add. */
static bool
-need_fake_edge_p (rtx insn)
+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)
- && !CONST_OR_PURE_CALL_P (insn)))
+ && !(RTL_CONST_OR_PURE_CALL_P (insn))))
return true;
return ((GET_CODE (PATTERN (insn)) == ASM_OPERANDS
e = find_edge (bb, EXIT_BLOCK_PTR);
if (e)
{
- insert_insn_on_edge (gen_rtx_USE (VOIDmode, const0_rtx), e);
+ insert_insn_on_edge (gen_use (const0_rtx), e);
commit_edge_insertions ();
}
}
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. */
+ 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
+ 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. */
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)
+ basic_block second_head ATTRIBUTE_UNUSED,
+ basic_block cond_bb, void *comp_rtx)
{
rtx label, seq, jump;
rtx op0 = XEXP ((rtx)comp_rtx, 0);
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);
+ mode, NULL_RTX, NULL_RTX, label, -1);
jump = get_last_insn ();
JUMP_LABEL (jump) = label;
LABEL_NUSES (label)++;
init_rtl_bb_info (basic_block bb)
{
gcc_assert (!bb->il.rtl);
- bb->il.rtl = ggc_alloc_cleared (sizeof (struct rtl_bb_info));
+ 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. */
-/* Add EXPR to the end of basic block BB. */
-
-rtx
-insert_insn_end_bb_new (rtx pat, basic_block bb)
+static bool
+rtl_can_remove_branch_p (const_edge e)
{
- rtx insn = BB_END (bb);
- rtx new_insn;
- rtx pat_end = pat;
-
- while (NEXT_INSN (pat_end) != NULL_RTX)
- pat_end = NEXT_INSN (pat_end);
+ 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;
- /* If the last insn is a jump, insert EXPR in front [taking care to
- handle cc0, etc. properly]. Similarly we need to care trapping
- instructions in presence of non-call exceptions. */
-
- if (JUMP_P (insn)
- || (NONJUMP_INSN_P (insn)
- && (!single_succ_p (bb)
- || single_succ_edge (bb)->flags & EDGE_ABNORMAL)))
- {
-#ifdef HAVE_cc0
- rtx note;
-#endif
- /* If this is a jump table, then we can't insert stuff here. Since
- we know the previous real insn must be the tablejump, we insert
- the new instruction just before the tablejump. */
- if (GET_CODE (PATTERN (insn)) == ADDR_VEC
- || GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC)
- insn = prev_real_insn (insn);
+ /* The conditions are taken from try_redirect_by_replacing_jump. */
+ if (target == EXIT_BLOCK_PTR)
+ return false;
-#ifdef HAVE_cc0
- /* FIXME: 'twould be nice to call prev_cc0_setter here but it aborts
- if cc0 isn't set. */
- note = find_reg_note (insn, REG_CC_SETTER, NULL_RTX);
- if (note)
- insn = XEXP (note, 0);
- else
- {
- rtx maybe_cc0_setter = prev_nonnote_insn (insn);
- if (maybe_cc0_setter
- && INSN_P (maybe_cc0_setter)
- && sets_cc0_p (PATTERN (maybe_cc0_setter)))
- insn = maybe_cc0_setter;
- }
-#endif
- /* FIXME: What if something in cc0/jump uses value set in new
- insn? */
- new_insn = emit_insn_before_noloc (pat, insn);
- }
+ if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH))
+ return false;
- /* Likewise if the last insn is a call, as will happen in the presence
- of exception handling. */
- else if (CALL_P (insn)
- && (!single_succ_p (bb)
- || single_succ_edge (bb)->flags & EDGE_ABNORMAL))
- {
- /* Keeping in mind SMALL_REGISTER_CLASSES and parameters in registers,
- we search backward and place the instructions before the first
- parameter is loaded. Do this for everyone for consistency and a
- presumption that we'll get better code elsewhere as well. */
+ if (find_reg_note (insn, REG_CROSSING_JUMP, NULL_RTX)
+ || BB_PARTITION (src) != BB_PARTITION (target))
+ return false;
- /* Since different machines initialize their parameter registers
- in different orders, assume nothing. Collect the set of all
- parameter registers. */
- insn = find_first_parameter_load (insn, BB_HEAD (bb));
+ if (!onlyjump_p (insn)
+ || tablejump_p (insn, NULL, NULL))
+ return false;
- /* If we found all the parameter loads, then we want to insert
- before the first parameter load.
+ set = single_set (insn);
+ if (!set || side_effects_p (set))
+ return false;
- If we did not find all the parameter loads, then we might have
- stopped on the head of the block, which could be a CODE_LABEL.
- If we inserted before the CODE_LABEL, then we would be putting
- the insn in the wrong basic block. In that case, put the insn
- after the CODE_LABEL. Also, respect NOTE_INSN_BASIC_BLOCK. */
- while (LABEL_P (insn)
- || NOTE_INSN_BASIC_BLOCK_P (insn))
- insn = NEXT_INSN (insn);
+ return true;
+}
- new_insn = emit_insn_before_noloc (pat, insn);
- }
- else
- new_insn = emit_insn_after_noloc (pat, insn);
+/* 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);
- return new_insn;
+static basic_block
+rtl_duplicate_bb (basic_block bb)
+{
+ bb = cfg_layout_duplicate_bb (bb);
+ bb->aux = NULL;
+ return bb;
}
/* Implementation of CFG manipulation for linearized RTL. */
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_merge_blocks,
rtl_predict_edge,
rtl_predicted_by_p,
- NULL, /* can_duplicate_block_p */
- NULL, /* duplicate_block */
+ cfg_layout_can_duplicate_bb_p,
+ rtl_duplicate_bb,
rtl_split_edge,
rtl_make_forwarder_block,
rtl_tidy_fallthru_edge,
+ rtl_force_nonfallthru,
rtl_block_ends_with_call_p,
rtl_block_ends_with_condjump_p,
rtl_flow_call_edges_add,
NULL, /* lv_add_condition_to_bb */
NULL, /* lv_adjust_loop_header_phi*/
NULL, /* extract_cond_bb_edges */
- NULL /* flush_pending_stmts */
+ NULL /* flush_pending_stmts */
};
/* Implementation of CFG manipulation for cfg layout RTL, where
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. */
-extern bool cfg_layout_can_duplicate_bb_p (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,
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_duplicate_bb,
cfg_layout_split_edge,
rtl_make_forwarder_block,
- NULL,
+ NULL, /* tidy_fallthru_edge */
+ rtl_force_nonfallthru,
rtl_block_ends_with_call_p,
rtl_block_ends_with_condjump_p,
rtl_flow_call_edges_add,
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 */
+ NULL /* flush_pending_stmts */
};
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