/* 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, 2006, 2007
- 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.
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 "flags.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"
+/* Holds the interesting leading and trailing notes for the function.
+ Only applicable if the CFG is in cfglayout mode. */
+static GTY(()) rtx cfg_layout_function_footer;
+static GTY(()) rtx cfg_layout_function_header;
+
+static rtx skip_insns_after_block (basic_block);
+static void record_effective_endpoints (void);
+static rtx label_for_bb (basic_block);
+static void fixup_reorder_chain (void);
+
+void verify_insn_chain (void);
+static void fixup_fallthru_exit_predecessor (void);
static int can_delete_note_p (const_rtx);
static int can_delete_label_p (const_rtx);
-static void commit_one_edge_insertion (edge);
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 (FILE *, basic_block, int, int);
static int rtl_verify_flow_info_1 (void);
static void rtl_make_forwarder_block (edge);
\f
static int
can_delete_note_p (const_rtx note)
{
- return (NOTE_KIND (note) == NOTE_INSN_DELETED
- || NOTE_KIND (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. */
&& !in_expr_list_p (forced_labels, label));
}
-/* Delete INSN by patching it out. Return the next insn. */
+/* Delete INSN by patching it out. */
-rtx
+void
delete_insn (rtx insn)
{
- rtx next = NEXT_INSN (insn);
rtx note;
bool really_delete = true;
if (! can_delete_label_p (insn))
{
const char *name = LABEL_NAME (insn);
+ basic_block bb = BLOCK_FOR_INSN (insn);
+ rtx bb_note = NEXT_INSN (insn);
really_delete = false;
PUT_CODE (insn, NOTE);
NOTE_KIND (insn) = NOTE_INSN_DELETED_LABEL;
NOTE_DELETED_LABEL_NAME (insn) = name;
+
+ if (bb_note != NULL_RTX && NOTE_INSN_BASIC_BLOCK_P (bb_note)
+ && BLOCK_FOR_INSN (bb_note) == bb)
+ {
+ reorder_insns_nobb (insn, insn, bb_note);
+ BB_HEAD (bb) = bb_note;
+ if (BB_END (bb) == bb_note)
+ BB_END (bb) = insn;
+ }
}
remove_node_from_expr_list (insn, &nonlocal_goto_handler_labels);
/* If 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)))
+ if (JUMP_P (insn))
{
- LABEL_NUSES (JUMP_LABEL (insn))--;
- JUMP_LABEL (insn) = NULL;
- }
+ if (JUMP_LABEL (insn)
+ && LABEL_P (JUMP_LABEL (insn)))
+ LABEL_NUSES (JUMP_LABEL (insn))--;
- /* Also if deleting an insn that references a label. */
- else
- {
- while ((note = find_reg_note (insn, REG_LABEL, NULL_RTX)) != NULL_RTX
+ /* 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;
LABEL_NUSES (label)--;
}
}
-
- return next;
}
/* Like delete_insn but also purge dead edges from BB. */
-rtx
+
+void
delete_insn_and_edges (rtx insn)
{
- rtx x;
bool purge = false;
if (INSN_P (insn)
&& BLOCK_FOR_INSN (insn)
&& BB_END (BLOCK_FOR_INSN (insn)) == insn)
purge = true;
- x = delete_insn (insn);
+ delete_insn (insn);
if (purge)
purge_dead_edges (BLOCK_FOR_INSN (insn));
- return x;
}
/* Unlink a chain of insns between START and FINISH, leaving notes
void
delete_insn_chain (rtx start, rtx finish, bool clear_bb)
{
- rtx next;
+ rtx prev, current;
/* Unchain the insns one by one. It would be quicker to delete all of these
with a single unchaining, rather than one at a time, but we need to keep
the NOTE's. */
+ current = finish;
while (1)
{
- next = NEXT_INSN (start);
- if (NOTE_P (start) && !can_delete_note_p (start))
+ prev = PREV_INSN (current);
+ if (NOTE_P (current) && !can_delete_note_p (current))
;
else
- next = delete_insn (start);
+ delete_insn (current);
- if (clear_bb && !INSN_DELETED_P (start))
- set_block_for_insn (start, NULL);
+ if (clear_bb && !INSN_DELETED_P (current))
+ set_block_for_insn (current, NULL);
- if (start == finish)
+ if (current == start)
break;
- start = next;
+ current = prev;
}
}
\f
}
/* 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)
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);
end = get_last_bb_insn (b);
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 */
+ OPTGROUP_NONE, /* optinfo_flags */
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. */
commit_edge_insertions ();
}
-/* Update insns block within BB. */
+/* 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
+/* Like active_insn_p, except keep the return value clobber around
+ even after reload. */
+
+static bool
+flow_active_insn_p (const_rtx insn)
+{
+ if (active_insn_p (insn))
+ return true;
+
+ /* A clobber of the function return value exists for buggy
+ programs that fail to return a value. Its effect is to
+ keep the return value from being live across the entire
+ function. If we allow it to be skipped, we introduce the
+ possibility for register lifetime confusion. */
+ if (GET_CODE (PATTERN (insn)) == CLOBBER
+ && REG_P (XEXP (PATTERN (insn), 0))
+ && REG_FUNCTION_VALUE_P (XEXP (PATTERN (insn), 0)))
+ return true;
+
+ return false;
+}
+
+/* Return true if the block has no effect and only forwards control flow to
+ its single destination. */
+
+bool
+contains_no_active_insn_p (const_basic_block bb)
+{
rtx insn;
- for (insn = BB_HEAD (bb); ; insn = NEXT_INSN (insn))
+ if (bb == EXIT_BLOCK_PTR || bb == ENTRY_BLOCK_PTR
+ || !single_succ_p (bb))
+ return false;
+
+ for (insn = BB_HEAD (bb); insn != BB_END (bb); insn = NEXT_INSN (insn))
+ if (INSN_P (insn) && flow_active_insn_p (insn))
+ return false;
+
+ return (!INSN_P (insn)
+ || (JUMP_P (insn) && simplejump_p (insn))
+ || !flow_active_insn_p (insn));
+}
+
+/* Likewise, but protect loop latches, headers and preheaders. */
+/* FIXME: Make this a cfg hook. */
+
+bool
+forwarder_block_p (const_basic_block bb)
+{
+ if (!contains_no_active_insn_p (bb))
+ return false;
+
+ /* Protect loop latches, headers and preheaders. */
+ if (current_loops)
{
- if (!BARRIER_P (insn))
- {
- set_block_for_insn (insn, bb);
- df_insn_change_bb (insn);
- }
- if (insn == BB_END (bb))
- break;
+ basic_block dest;
+ if (bb->loop_father->header == bb)
+ return false;
+ dest = EDGE_SUCC (bb, 0)->dest;
+ if (dest->loop_father->header == dest)
+ return false;
}
+
+ return true;
+}
+
+/* Return nonzero if we can reach target from src by falling through. */
+/* FIXME: Make this a cfg hook. */
+
+bool
+can_fallthru (basic_block src, basic_block target)
+{
+ rtx insn = BB_END (src);
+ rtx insn2;
+ edge e;
+ edge_iterator ei;
+
+ if (target == EXIT_BLOCK_PTR)
+ return true;
+ if (src->next_bb != target)
+ return 0;
+ FOR_EACH_EDGE (e, ei, src->succs)
+ if (e->dest == EXIT_BLOCK_PTR
+ && e->flags & EDGE_FALLTHRU)
+ return 0;
+
+ insn2 = BB_HEAD (target);
+ if (insn2 && !active_insn_p (insn2))
+ insn2 = next_active_insn (insn2);
+
+ /* ??? Later we may add code to move jump tables offline. */
+ return next_active_insn (insn) == insn2;
+}
+
+/* Return nonzero if we could reach target from src by falling through,
+ if the target was made adjacent. If we already have a fall-through
+ edge to the exit block, we can't do that. */
+static bool
+could_fall_through (basic_block src, basic_block target)
+{
+ edge e;
+ edge_iterator ei;
+
+ if (target == EXIT_BLOCK_PTR)
+ return true;
+ FOR_EACH_EDGE (e, ei, src->succs)
+ if (e->dest == EXIT_BLOCK_PTR
+ && e->flags & EDGE_FALLTHRU)
+ return 0;
+ return true;
}
\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. */
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 ();
}
return new_bb;
}
+/* Return true if the single edge between blocks A and B is the only place
+ in RTL which holds some unique locus. */
+
+static bool
+unique_locus_on_edge_between_p (basic_block a, basic_block b)
+{
+ const location_t goto_locus = EDGE_SUCC (a, 0)->goto_locus;
+ rtx insn, end;
+
+ if (LOCATION_LOCUS (goto_locus) == UNKNOWN_LOCATION)
+ return false;
+
+ /* First scan block A backward. */
+ insn = BB_END (a);
+ end = PREV_INSN (BB_HEAD (a));
+ while (insn != end && (!NONDEBUG_INSN_P (insn) || !INSN_HAS_LOCATION (insn)))
+ insn = PREV_INSN (insn);
+
+ if (insn != end && INSN_LOCATION (insn) == goto_locus)
+ return false;
+
+ /* Then scan block B forward. */
+ insn = BB_HEAD (b);
+ if (insn)
+ {
+ end = NEXT_INSN (BB_END (b));
+ while (insn != end && !NONDEBUG_INSN_P (insn))
+ insn = NEXT_INSN (insn);
+
+ if (insn != end && INSN_HAS_LOCATION (insn)
+ && INSN_LOCATION (insn) == goto_locus)
+ return false;
+ }
+
+ return true;
+}
+
+/* If the single edge between blocks A and B is the only place in RTL which
+ holds some unique locus, emit a nop with that locus between the blocks. */
+
+static void
+emit_nop_for_unique_locus_between (basic_block a, basic_block b)
+{
+ if (!unique_locus_on_edge_between_p (a, b))
+ return;
+
+ BB_END (a) = emit_insn_after_noloc (gen_nop (), BB_END (a), a);
+ INSN_LOCATION (BB_END (a)) = EDGE_SUCC (a, 0)->goto_locus;
+}
+
/* Blocks A and B are to be merged into a single block A. The insns
are already contiguous. */
{
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);
+ 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)
/* Delete everything marked above as well as crap that might be
hanging out between the two blocks. */
- BB_HEAD (b) = NULL;
+ BB_END (a) = a_end;
+ BB_HEAD (b) = b_empty ? NULL_RTX : b_head;
delete_insn_chain (del_first, del_last, true);
+ /* When not optimizing CFG and the edge is the only place in RTL which holds
+ some unique locus, emit a nop with that locus in between. */
+ if (!optimize)
+ {
+ emit_nop_for_unique_locus_between (a, b);
+ a_end = BB_END (a);
+ }
+
/* Reassociate the insns of B with A. */
if (!b_empty)
{
- rtx x;
-
- for (x = a_end; x != b_end; x = NEXT_INSN (x))
- {
- set_block_for_insn (x, a);
- df_insn_change_bb (x);
- }
+ update_bb_for_insn_chain (a_end, b_debug_end, a);
- set_block_for_insn (b_end, a);
- df_insn_change_bb (b_end);
-
- a_end = b_end;
+ BB_END (a) = b_debug_end;
+ BB_HEAD (b) = NULL_RTX;
+ }
+ else if (b_end != b_debug_end)
+ {
+ /* Move any deleted labels and other notes between the end of A
+ and the debug insns that make up B after the debug insns,
+ bringing the debug insns into A while keeping the notes after
+ the end of A. */
+ if (NEXT_INSN (a_end) != b_debug_start)
+ reorder_insns_nobb (NEXT_INSN (a_end), PREV_INSN (b_debug_start),
+ b_debug_end);
+ update_bb_for_insn_chain (b_debug_start, b_debug_end, a);
+ BB_END (a) = b_debug_end;
}
df_bb_delete (b->index);
- BB_END (a) = a_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);
}
if (BB_PARTITION (a) != BB_PARTITION (b))
return false;
+ /* Protect the loop latches. */
+ if (current_loops && b->loop_father->latch == b)
+ return false;
+
/* There must be exactly one edge in between the blocks. */
return (single_succ_p (a)
&& single_succ (a) == b
/* Selectively unlink whole insn chain. */
if (in_cfglayout)
{
- rtx insn = src->il.rtl->footer;
+ rtx insn = BB_FOOTER (src);
delete_insn_chain (kill_from, BB_END (src), false);
if (PREV_INSN (insn))
NEXT_INSN (PREV_INSN (insn)) = NEXT_INSN (insn);
else
- src->il.rtl->footer = NEXT_INSN (insn);
+ BB_FOOTER (src) = NEXT_INSN (insn);
if (NEXT_INSN (insn))
PREV_INSN (NEXT_INSN (insn)) = PREV_INSN (insn);
}
{
rtx target_label = block_label (target);
rtx barrier, label, table;
- bool jump_p;
emit_jump_insn_after_noloc (gen_jump (target_label), insn);
JUMP_LABEL (BB_END (src)) = target_label;
INSN_UID (insn), INSN_UID (BB_END (src)));
+ delete_insn_chain (kill_from, insn, false);
+
/* Recognize a tablejump that we are converting to a
simple jump and remove its associated CODE_LABEL
and ADDR_VEC or ADDR_DIFF_VEC. */
- jump_p = tablejump_p (insn, &label, &table);
-
- delete_insn_chain (kill_from, insn, false);
- if (jump_p)
- delete_insn_chain (label, table, false);
+ if (tablejump_p (insn, &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);
- df_insn_change_bb (tmp);
- }
+ 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);
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",
}
/* 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
one and create separate abnormal edge to original destination.
This allows bb-reorder to make such edge non-fallthru. */
gcc_assert (e->dest == target);
- abnormal_edge_flags = e->flags & ~(EDGE_FALLTHRU | EDGE_CAN_FALLTHRU);
- e->flags &= EDGE_FALLTHRU | EDGE_CAN_FALLTHRU;
+ abnormal_edge_flags = e->flags & ~EDGE_FALLTHRU;
+ e->flags &= EDGE_FALLTHRU;
}
else
{
}
}
- 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;
/* 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;
+ loc = e->goto_locus;
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 ();
+ gcc_unreachable ();
#endif
+ }
+ else
+ {
+ gcc_assert (jump_label == simple_return_rtx);
+#ifdef HAVE_simple_return
+ emit_jump_insn_after_setloc (gen_simple_return (),
+ BB_END (jump_block), loc);
+#else
+ gcc_unreachable ();
+#endif
+ }
+ set_return_jump_label (BB_END (jump_block));
}
else
{
rtx label = block_label (target);
- emit_jump_insn_after_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 ();
+ 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. */
df_set_bb_dirty (e->src);
- return force_nonfallthru_and_redirect (e, target);
+ return force_nonfallthru_and_redirect (e, target, NULL_RTX);
}
/* The given edge should potentially be a fallthru edge. If that is in
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);
gcc_assert (redirected);
}
else
- redirect_edge_succ (edge_in, bb);
-
- return 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;
+}
/* Queue instructions for insertion on an edge between two basic blocks.
The new instructions and basic blocks (if any) will not appear in the
/* Update the CFG for the instructions queued on edge E. */
-static void
+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;
- 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;
+ /* 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)
+ {
+ 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 ();
+ }
- /* 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);
+ /* We'd better be fallthru, or we've lost track of what's what. */
+ gcc_assert (e->flags & EDGE_FALLTHRU);
+
after = BB_END (bb);
+ }
+ }
- 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_INSN_BASIC_BLOCK_P (cur_insn))
- {
- bb_note = cur_insn;
- break;
- }
+ /* Otherwise we must split the edge. */
+ else
+ {
+ bb = split_edge (e);
+ after = BB_END (bb);
- 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)));
- }
- }
+ 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, bb);
}
else
gcc_assert (!JUMP_P (last));
-
- /* Mark the basic block for find_many_sub_basic_blocks. */
- if (current_ir_type () != IR_RTL_CFGLAYOUT)
- 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);
- }
+ commit_one_edge_insertion (e);
}
-
- if (!changed)
- return;
-
- /* In the old rtl CFG API, it was OK to insert control flow on an
- edge, apparently? In cfglayout mode, this will *not* work, and
- the caller is responsible for making sure that control flow is
- valid at all times. */
- if (current_ir_type () == IR_RTL_CFGLAYOUT)
- 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). */
+ at start and end with TDF_DETAILS). FLAGS are the TDF_* masks
+ documented in dumpfile.h. */
static void
-rtl_dump_bb (basic_block bb, FILE *outf, int indent)
+rtl_dump_bb (FILE *outf, basic_block bb, int indent, int flags)
{
rtx insn;
rtx last;
s_indent = (char *) alloca ((size_t) indent + 1);
memset (s_indent, ' ', (size_t) indent);
s_indent[indent] = '\0';
-
- if (df)
+
+ if (df && (flags & TDF_DETAILS))
{
df_dump_top (bb, outf);
putc ('\n', outf);
}
- for (insn = BB_HEAD (bb), last = NEXT_INSN (BB_END (bb)); insn != last;
- insn = NEXT_INSN (insn))
- print_rtl_single (outf, insn);
+ if (bb->index != ENTRY_BLOCK && bb->index != EXIT_BLOCK)
+ for (insn = BB_HEAD (bb), last = NEXT_INSN (BB_END (bb)); insn != last;
+ insn = NEXT_INSN (insn))
+ {
+ if (flags & TDF_DETAILS)
+ df_dump_insn_top (insn, outf);
+ if (! (flags & TDF_SLIM))
+ print_rtl_single (outf, insn);
+ else
+ dump_insn_slim (outf, insn);
+ if (flags & TDF_DETAILS)
+ df_dump_insn_bottom (insn, outf);
+ }
- if (df)
+ if (df && (flags & TDF_DETAILS))
{
df_dump_bottom (bb, outf);
putc ('\n', outf);
}
\f
-/* Like print_rtl, but also print out live information for the start of each
- basic block. */
+/* Like dump_function_to_file, but for RTL. Print out dataflow information
+ for the start of each basic block. FLAGS are the TDF_* masks documented
+ in dumpfile.h. */
void
-print_rtl_with_bb (FILE *outf, const_rtx rtx_first)
+print_rtl_with_bb (FILE *outf, const_rtx rtx_first, int flags)
{
const_rtx tmp_rtx;
if (rtx_first == 0)
basic_block *start = XCNEWVEC (basic_block, max_uid);
basic_block *end = XCNEWVEC (basic_block, max_uid);
enum bb_state *in_bb_p = XCNEWVEC (enum bb_state, max_uid);
-
basic_block bb;
+ /* After freeing the CFG, we still have BLOCK_FOR_INSN set on most
+ insns, but the CFG is not maintained so the basic block info
+ is not reliable. Therefore it's omitted from the dumps. */
+ if (! (cfun->curr_properties & PROP_cfg))
+ flags &= ~TDF_BLOCKS;
+
if (df)
df_dump_start (outf);
- FOR_EACH_BB_REVERSE (bb)
+ if (flags & TDF_BLOCKS)
{
- rtx x;
-
- start[INSN_UID (BB_HEAD (bb))] = bb;
- end[INSN_UID (BB_END (bb))] = bb;
- for (x = BB_HEAD (bb); x != NULL_RTX; x = NEXT_INSN (x))
+ FOR_EACH_BB_REVERSE (bb)
{
- enum bb_state state = IN_MULTIPLE_BB;
+ rtx x;
+
+ start[INSN_UID (BB_HEAD (bb))] = bb;
+ end[INSN_UID (BB_END (bb))] = bb;
+ for (x = BB_HEAD (bb); x != NULL_RTX; x = NEXT_INSN (x))
+ {
+ enum bb_state state = IN_MULTIPLE_BB;
- if (in_bb_p[INSN_UID (x)] == NOT_IN_BB)
- state = IN_ONE_BB;
- in_bb_p[INSN_UID (x)] = state;
+ if (in_bb_p[INSN_UID (x)] == NOT_IN_BB)
+ state = IN_ONE_BB;
+ in_bb_p[INSN_UID (x)] = state;
- if (x == BB_END (bb))
- break;
+ 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)
+ if (flags & TDF_BLOCKS)
{
- 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)
+ bb = start[INSN_UID (tmp_rtx)];
+ if (bb != NULL)
{
- fputs (";; Pred edge ", outf);
- dump_edge_info (outf, e, 0);
- fputc ('\n', outf);
+ dump_bb_info (outf, bb, 0, dump_flags | TDF_COMMENT, true, false);
+ if (df && (flags & TDF_DETAILS))
+ df_dump_top (bb, outf);
}
- }
- if (in_bb_p[INSN_UID (tmp_rtx)] == NOT_IN_BB
- && !NOTE_P (tmp_rtx)
- && !BARRIER_P (tmp_rtx))
- fprintf (outf, ";; Insn is not within a basic block\n");
- else if (in_bb_p[INSN_UID (tmp_rtx)] == IN_MULTIPLE_BB)
- fprintf (outf, ";; Insn is in multiple basic blocks\n");
+ if (in_bb_p[INSN_UID (tmp_rtx)] == NOT_IN_BB
+ && !NOTE_P (tmp_rtx)
+ && !BARRIER_P (tmp_rtx))
+ fprintf (outf, ";; Insn is not within a basic block\n");
+ else if (in_bb_p[INSN_UID (tmp_rtx)] == IN_MULTIPLE_BB)
+ fprintf (outf, ";; Insn is in multiple basic blocks\n");
+ }
- did_output = print_rtl_single (outf, tmp_rtx);
+ if (flags & TDF_DETAILS)
+ df_dump_insn_top (tmp_rtx, outf);
+ if (! (flags & TDF_SLIM))
+ print_rtl_single (outf, tmp_rtx);
+ else
+ dump_insn_slim (outf, tmp_rtx);
+ if (flags & TDF_DETAILS)
+ df_dump_insn_bottom (tmp_rtx, outf);
- if ((bb = end[INSN_UID (tmp_rtx)]) != NULL)
+ if (flags & TDF_BLOCKS)
{
- 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)
+ bb = end[INSN_UID (tmp_rtx)];
+ if (bb != NULL)
{
- df_dump_bottom (bb, outf);
+ dump_bb_info (outf, bb, 0, dump_flags | TDF_COMMENT, false, true);
+ if (df && (flags & TDF_DETAILS))
+ df_dump_bottom (bb, outf);
putc ('\n', outf);
}
- 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 (start);
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
+/* Update the branch probability of BB if a REG_BR_PROB is present. */
+
void
update_br_prob_note (basic_block bb)
{
end = tmp;
/* Include any barriers that may follow the basic block. */
- tmp = next_nonnote_insn (end);
+ tmp = next_nonnote_insn_bb (end);
while (tmp && BARRIER_P (tmp))
{
end = tmp;
- tmp = next_nonnote_insn (end);
+ tmp = next_nonnote_insn_bb (end);
}
return end;
err = 1;
}
- for (insn = bb->il.rtl->header; insn; insn = NEXT_INSN (insn))
+ for (insn = BB_HEADER (bb); insn; insn = NEXT_INSN (insn))
if (!BARRIER_P (insn)
&& BLOCK_FOR_INSN (insn) != NULL)
{
INSN_UID (insn), bb->index);
err = 1;
}
- for (insn = bb->il.rtl->footer; insn; insn = NEXT_INSN (insn))
+ for (insn = BB_FOOTER (bb); insn; insn = NEXT_INSN (insn))
if (!BARRIER_P (insn)
&& BLOCK_FOR_INSN (insn) != NULL)
{
}
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))
FOR_EACH_BB_REVERSE (bb)
{
edge e;
- edge_iterator ei;
rtx head = BB_HEAD (bb);
rtx end = BB_END (bb);
last_head = PREV_INSN (x);
- FOR_EACH_EDGE (e, ei, bb->succs)
- if (e->flags & EDGE_FALLTHRU)
- break;
+ 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_INSN_BASIC_BLOCK_P (insn))
+ 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)
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. */
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);
- df_set_bb_dirty (bb);
- purged = true;
+ ei_next (&ei);
}
if (JUMP_P (insn))
return purged;
}
-/* Same as split_block but update cfg_layout structures. */
+/* 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.
-static basic_block
-cfg_layout_split_block (basic_block bb, void *insnp)
+ Similarly, handle instructions throwing exceptions internally.
+
+ Return true when instructions have been found and inserted on edges. */
+
+bool
+fixup_abnormal_edges (void)
{
- rtx insn = (rtx) insnp;
- basic_block new_bb = rtl_split_block (bb, insn);
+ bool inserted = false;
+ basic_block bb;
+
+ FOR_EACH_BB (bb)
+ {
+ edge e;
+ edge_iterator ei;
- new_bb->il.rtl->footer = bb->il.rtl->footer;
- bb->il.rtl->footer = NULL;
+ /* 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;
- return new_bb;
-}
+ if (e && !CALL_P (BB_END (bb)) && !can_throw_internal (BB_END (bb)))
+ {
+ rtx insn;
-/* Redirect Edge to DEST. */
-static edge
-cfg_layout_redirect_edge_and_branch (edge e, basic_block dest)
-{
- basic_block src = e->src;
- edge ret;
+ /* 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 (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH))
- return NULL;
+ if (CALL_P (insn) || can_throw_internal (insn))
+ {
+ rtx stop, next;
- if (e->dest == dest)
- return e;
+ e = find_fallthru_edge (bb->succs);
- if (e->src != ENTRY_BLOCK_PTR
- && (ret = try_redirect_by_replacing_jump (e, dest, true)))
- {
- df_set_bb_dirty (src);
- return ret;
- }
+ stop = NEXT_INSN (BB_END (bb));
+ BB_END (bb) = insn;
- 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);
+ 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);
+ }
+ }
- df_set_bb_dirty (e->src);
- redirect_edge_succ (e, dest);
- return e;
+ /* 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);
+ }
}
- /* 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. */
+ return inserted;
+}
+\f
+/* Cut the insns from FIRST to LAST out of the insns stream. */
- if (e->flags & EDGE_FALLTHRU)
+rtx
+unlink_insn_chain (rtx first, rtx last)
+{
+ rtx prevfirst = PREV_INSN (first);
+ rtx nextlast = NEXT_INSN (last);
+
+ PREV_INSN (first) = NULL;
+ NEXT_INSN (last) = NULL;
+ if (prevfirst)
+ NEXT_INSN (prevfirst) = nextlast;
+ if (nextlast)
+ PREV_INSN (nextlast) = prevfirst;
+ else
+ set_last_insn (prevfirst);
+ if (!prevfirst)
+ set_first_insn (nextlast);
+ return first;
+}
+\f
+/* Skip over inter-block insns occurring after BB which are typically
+ associated with BB (e.g., barriers). If there are any such insns,
+ we return the last one. Otherwise, we return the end of BB. */
+
+static rtx
+skip_insns_after_block (basic_block bb)
+{
+ rtx insn, last_insn, next_head, prev;
+
+ next_head = NULL_RTX;
+ if (bb->next_bb != EXIT_BLOCK_PTR)
+ next_head = BB_HEAD (bb->next_bb);
+
+ for (last_insn = insn = BB_END (bb); (insn = NEXT_INSN (insn)) != 0; )
{
- /* 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 (insn == next_head)
+ break;
- 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);
- e->flags |= EDGE_FALLTHRU;
- df_set_bb_dirty (e->src);
- return e;
- }
- /* In case we are redirecting fallthru edge to the branch edge
- of conditional jump, remove it. */
- if (EDGE_COUNT (src->succs) == 2)
+ switch (GET_CODE (insn))
{
- /* Find the edge that is different from E. */
- edge s = EDGE_SUCC (src, EDGE_SUCC (src, 0) == e);
+ case BARRIER:
+ last_insn = insn;
+ continue;
- if (s->dest == dest
- && any_condjump_p (BB_END (src))
- && onlyjump_p (BB_END (src)))
- delete_insn (BB_END (src));
+ case NOTE:
+ switch (NOTE_KIND (insn))
+ {
+ case NOTE_INSN_BLOCK_END:
+ gcc_unreachable ();
+ continue;
+ default:
+ continue;
+ break;
+ }
+ break;
+
+ case CODE_LABEL:
+ if (NEXT_INSN (insn)
+ && JUMP_TABLE_DATA_P (NEXT_INSN (insn)))
+ {
+ insn = NEXT_INSN (insn);
+ last_insn = insn;
+ continue;
+ }
+ break;
+
+ default:
+ break;
}
- ret = redirect_edge_succ_nodup (e, dest);
- if (dump_file)
- fprintf (dump_file, "Fallthru edge %i->%i redirected to %i\n",
- e->src->index, e->dest->index, dest->index);
+
+ break;
}
- 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)));
+ /* It is possible to hit contradictory sequence. For instance:
- df_set_bb_dirty (src);
- return ret;
-}
+ jump_insn
+ NOTE_INSN_BLOCK_BEG
+ barrier
-/* 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);
+ Where barrier belongs to jump_insn, but the note does not. This can be
+ created by removing the basic block originally following
+ NOTE_INSN_BLOCK_BEG. In such case reorder the notes. */
- gcc_assert (redirected);
- return NULL;
+ for (insn = last_insn; insn != BB_END (bb); insn = prev)
+ {
+ prev = PREV_INSN (insn);
+ if (NOTE_P (insn))
+ switch (NOTE_KIND (insn))
+ {
+ case NOTE_INSN_BLOCK_END:
+ gcc_unreachable ();
+ break;
+ case NOTE_INSN_DELETED:
+ case NOTE_INSN_DELETED_LABEL:
+ case NOTE_INSN_DELETED_DEBUG_LABEL:
+ continue;
+ default:
+ reorder_insns (insn, insn, last_insn);
+ }
+ }
+
+ return last_insn;
}
-/* Same as delete_basic_block but update cfg_layout structures. */
+/* Locate or create a label for a given basic block. */
-static void
-cfg_layout_delete_block (basic_block bb)
+static rtx
+label_for_bb (basic_block bb)
{
- rtx insn, next, prev = PREV_INSN (BB_HEAD (bb)), *to, remaints;
+ rtx label = BB_HEAD (bb);
- if (bb->il.rtl->header)
+ if (!LABEL_P (label))
+ {
+ if (dump_file)
+ fprintf (dump_file, "Emitting label for block %d\n", bb->index);
+
+ label = block_label (bb);
+ }
+
+ return label;
+}
+
+/* Locate the effective beginning and end of the insn chain for each
+ block, as defined by skip_insns_after_block above. */
+
+static void
+record_effective_endpoints (void)
+{
+ rtx next_insn;
+ basic_block bb;
+ rtx insn;
+
+ for (insn = get_insns ();
+ insn
+ && NOTE_P (insn)
+ && NOTE_KIND (insn) != NOTE_INSN_BASIC_BLOCK;
+ insn = NEXT_INSN (insn))
+ continue;
+ /* No basic blocks at all? */
+ gcc_assert (insn);
+
+ if (PREV_INSN (insn))
+ cfg_layout_function_header =
+ unlink_insn_chain (get_insns (), PREV_INSN (insn));
+ else
+ cfg_layout_function_header = NULL_RTX;
+
+ next_insn = get_insns ();
+ FOR_EACH_BB (bb)
+ {
+ rtx end;
+
+ if (PREV_INSN (BB_HEAD (bb)) && next_insn != BB_HEAD (bb))
+ BB_HEADER (bb) = unlink_insn_chain (next_insn,
+ PREV_INSN (BB_HEAD (bb)));
+ end = skip_insns_after_block (bb);
+ if (NEXT_INSN (BB_END (bb)) && BB_END (bb) != end)
+ BB_FOOTER (bb) = unlink_insn_chain (NEXT_INSN (BB_END (bb)), end);
+ next_insn = NEXT_INSN (BB_END (bb));
+ }
+
+ cfg_layout_function_footer = next_insn;
+ if (cfg_layout_function_footer)
+ cfg_layout_function_footer = unlink_insn_chain (cfg_layout_function_footer, get_last_insn ());
+}
+\f
+static unsigned int
+into_cfg_layout_mode (void)
+{
+ cfg_layout_initialize (0);
+ return 0;
+}
+
+static unsigned int
+outof_cfg_layout_mode (void)
+{
+ basic_block bb;
+
+ FOR_EACH_BB (bb)
+ if (bb->next_bb != EXIT_BLOCK_PTR)
+ bb->aux = bb->next_bb;
+
+ cfg_layout_finalize ();
+
+ return 0;
+}
+
+struct rtl_opt_pass pass_into_cfg_layout_mode =
+{
+ {
+ RTL_PASS,
+ "into_cfglayout", /* name */
+ OPTGROUP_NONE, /* optinfo_flags */
+ NULL, /* gate */
+ into_cfg_layout_mode, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ TV_CFG, /* tv_id */
+ 0, /* properties_required */
+ PROP_cfglayout, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ 0 /* todo_flags_finish */
+ }
+};
+
+struct rtl_opt_pass pass_outof_cfg_layout_mode =
+{
+ {
+ RTL_PASS,
+ "outof_cfglayout", /* name */
+ OPTGROUP_NONE, /* optinfo_flags */
+ NULL, /* gate */
+ outof_cfg_layout_mode, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ TV_CFG, /* tv_id */
+ 0, /* properties_required */
+ 0, /* properties_provided */
+ PROP_cfglayout, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ 0 /* todo_flags_finish */
+ }
+};
+\f
+
+/* Link the basic blocks in the correct order, compacting the basic
+ block queue while at it. If STAY_IN_CFGLAYOUT_MODE is false, this
+ function also clears the basic block header and footer fields.
+
+ This function is usually called after a pass (e.g. tracer) finishes
+ some transformations while in cfglayout mode. The required sequence
+ of the basic blocks is in a linked list along the bb->aux field.
+ This functions re-links the basic block prev_bb and next_bb pointers
+ accordingly, and it compacts and renumbers the blocks.
+
+ FIXME: This currently works only for RTL, but the only RTL-specific
+ bits are the STAY_IN_CFGLAYOUT_MODE bits. The tracer pass was moved
+ to GIMPLE a long time ago, but it doesn't relink the basic block
+ chain. It could do that (to give better initial RTL) if this function
+ is made IR-agnostic (and moved to cfganal.c or cfg.c while at it). */
+
+void
+relink_block_chain (bool stay_in_cfglayout_mode)
+{
+ basic_block bb, prev_bb;
+ int index;
+
+ /* Maybe dump the re-ordered sequence. */
+ if (dump_file)
+ {
+ fprintf (dump_file, "Reordered sequence:\n");
+ for (bb = ENTRY_BLOCK_PTR->next_bb, index = NUM_FIXED_BLOCKS;
+ bb;
+ bb = (basic_block) bb->aux, index++)
+ {
+ fprintf (dump_file, " %i ", index);
+ if (get_bb_original (bb))
+ fprintf (dump_file, "duplicate of %i ",
+ get_bb_original (bb)->index);
+ else if (forwarder_block_p (bb)
+ && !LABEL_P (BB_HEAD (bb)))
+ fprintf (dump_file, "compensation ");
+ else
+ fprintf (dump_file, "bb %i ", bb->index);
+ fprintf (dump_file, " [%i]\n", bb->frequency);
+ }
+ }
+
+ /* Now reorder the blocks. */
+ prev_bb = ENTRY_BLOCK_PTR;
+ bb = ENTRY_BLOCK_PTR->next_bb;
+ for (; bb; prev_bb = bb, bb = (basic_block) bb->aux)
+ {
+ bb->prev_bb = prev_bb;
+ prev_bb->next_bb = bb;
+ }
+ prev_bb->next_bb = EXIT_BLOCK_PTR;
+ EXIT_BLOCK_PTR->prev_bb = prev_bb;
+
+ /* Then, clean up the aux fields. */
+ FOR_ALL_BB (bb)
+ {
+ bb->aux = NULL;
+ if (!stay_in_cfglayout_mode)
+ BB_HEADER (bb) = BB_FOOTER (bb) = NULL;
+ }
+
+ /* Maybe reset the original copy tables, they are not valid anymore
+ when we renumber the basic blocks in compact_blocks. If we are
+ are going out of cfglayout mode, don't re-allocate the tables. */
+ free_original_copy_tables ();
+ if (stay_in_cfglayout_mode)
+ initialize_original_copy_tables ();
+
+ /* Finally, put basic_block_info in the new order. */
+ compact_blocks ();
+}
+\f
+
+/* Given a reorder chain, rearrange the code to match. */
+
+static void
+fixup_reorder_chain (void)
+{
+ basic_block bb;
+ rtx insn = NULL;
+
+ if (cfg_layout_function_header)
+ {
+ set_first_insn (cfg_layout_function_header);
+ insn = cfg_layout_function_header;
+ while (NEXT_INSN (insn))
+ insn = NEXT_INSN (insn);
+ }
+
+ /* First do the bulk reordering -- rechain the blocks without regard to
+ the needed changes to jumps and labels. */
+
+ for (bb = ENTRY_BLOCK_PTR->next_bb; bb; bb = (basic_block) bb->aux)
+ {
+ if (BB_HEADER (bb))
+ {
+ if (insn)
+ NEXT_INSN (insn) = BB_HEADER (bb);
+ else
+ set_first_insn (BB_HEADER (bb));
+ PREV_INSN (BB_HEADER (bb)) = insn;
+ insn = BB_HEADER (bb);
+ while (NEXT_INSN (insn))
+ insn = NEXT_INSN (insn);
+ }
+ if (insn)
+ NEXT_INSN (insn) = BB_HEAD (bb);
+ else
+ set_first_insn (BB_HEAD (bb));
+ PREV_INSN (BB_HEAD (bb)) = insn;
+ insn = BB_END (bb);
+ if (BB_FOOTER (bb))
+ {
+ NEXT_INSN (insn) = BB_FOOTER (bb);
+ PREV_INSN (BB_FOOTER (bb)) = insn;
+ while (NEXT_INSN (insn))
+ insn = NEXT_INSN (insn);
+ }
+ }
+
+ NEXT_INSN (insn) = cfg_layout_function_footer;
+ if (cfg_layout_function_footer)
+ PREV_INSN (cfg_layout_function_footer) = insn;
+
+ while (NEXT_INSN (insn))
+ insn = NEXT_INSN (insn);
+
+ set_last_insn (insn);
+#ifdef ENABLE_CHECKING
+ verify_insn_chain ();
+#endif
+
+ /* Now add jumps and labels as needed to match the blocks new
+ outgoing edges. */
+
+ for (bb = ENTRY_BLOCK_PTR->next_bb; bb ; bb = (basic_block) bb->aux)
+ {
+ edge e_fall, e_taken, e;
+ rtx bb_end_insn;
+ rtx ret_label = NULL_RTX;
+ basic_block nb, src_bb;
+ edge_iterator ei;
+
+ if (EDGE_COUNT (bb->succs) == 0)
+ continue;
+
+ /* Find the old fallthru edge, and another non-EH edge for
+ a taken jump. */
+ e_taken = e_fall = NULL;
+
+ FOR_EACH_EDGE (e, ei, bb->succs)
+ if (e->flags & EDGE_FALLTHRU)
+ e_fall = e;
+ else if (! (e->flags & EDGE_EH))
+ e_taken = e;
+
+ bb_end_insn = BB_END (bb);
+ if (JUMP_P (bb_end_insn))
+ {
+ ret_label = JUMP_LABEL (bb_end_insn);
+ if (any_condjump_p (bb_end_insn))
+ {
+ /* This might happen if the conditional jump has side
+ effects and could therefore not be optimized away.
+ Make the basic block to end with a barrier in order
+ to prevent rtl_verify_flow_info from complaining. */
+ if (!e_fall)
+ {
+ gcc_assert (!onlyjump_p (bb_end_insn)
+ || returnjump_p (bb_end_insn));
+ BB_FOOTER (bb) = emit_barrier_after (bb_end_insn);
+ continue;
+ }
+
+ /* If the old fallthru is still next, nothing to do. */
+ if (bb->aux == e_fall->dest
+ || e_fall->dest == EXIT_BLOCK_PTR)
+ continue;
+
+ /* The degenerated case of conditional jump jumping to the next
+ instruction can happen for jumps with side effects. We need
+ to construct a forwarder block and this will be done just
+ fine by force_nonfallthru below. */
+ if (!e_taken)
+ ;
+
+ /* There is another special case: if *neither* block is next,
+ such as happens at the very end of a function, then we'll
+ need to add a new unconditional jump. Choose the taken
+ edge based on known or assumed probability. */
+ else if (bb->aux != e_taken->dest)
+ {
+ rtx note = find_reg_note (bb_end_insn, REG_BR_PROB, 0);
+
+ if (note
+ && INTVAL (XEXP (note, 0)) < REG_BR_PROB_BASE / 2
+ && invert_jump (bb_end_insn,
+ (e_fall->dest == EXIT_BLOCK_PTR
+ ? NULL_RTX
+ : label_for_bb (e_fall->dest)), 0))
+ {
+ e_fall->flags &= ~EDGE_FALLTHRU;
+ gcc_checking_assert (could_fall_through
+ (e_taken->src, e_taken->dest));
+ e_taken->flags |= EDGE_FALLTHRU;
+ update_br_prob_note (bb);
+ e = e_fall, e_fall = e_taken, e_taken = e;
+ }
+ }
+
+ /* If the "jumping" edge is a crossing edge, and the fall
+ through edge is non-crossing, leave things as they are. */
+ else if ((e_taken->flags & EDGE_CROSSING)
+ && !(e_fall->flags & EDGE_CROSSING))
+ continue;
+
+ /* Otherwise we can try to invert the jump. This will
+ basically never fail, however, keep up the pretense. */
+ else if (invert_jump (bb_end_insn,
+ (e_fall->dest == EXIT_BLOCK_PTR
+ ? NULL_RTX
+ : label_for_bb (e_fall->dest)), 0))
+ {
+ e_fall->flags &= ~EDGE_FALLTHRU;
+ gcc_checking_assert (could_fall_through
+ (e_taken->src, e_taken->dest));
+ e_taken->flags |= EDGE_FALLTHRU;
+ update_br_prob_note (bb);
+ if (LABEL_NUSES (ret_label) == 0
+ && single_pred_p (e_taken->dest))
+ delete_insn (ret_label);
+ continue;
+ }
+ }
+ else if (extract_asm_operands (PATTERN (bb_end_insn)) != NULL)
+ {
+ /* If the old fallthru is still next or if
+ asm goto doesn't have a fallthru (e.g. when followed by
+ __builtin_unreachable ()), nothing to do. */
+ if (! e_fall
+ || bb->aux == e_fall->dest
+ || e_fall->dest == EXIT_BLOCK_PTR)
+ continue;
+
+ /* Otherwise we'll have to use the fallthru fixup below. */
+ }
+ else
+ {
+ /* Otherwise we have some return, switch or computed
+ jump. In the 99% case, there should not have been a
+ fallthru edge. */
+ gcc_assert (returnjump_p (bb_end_insn) || !e_fall);
+ continue;
+ }
+ }
+ else
+ {
+ /* No fallthru implies a noreturn function with EH edges, or
+ something similarly bizarre. In any case, we don't need to
+ do anything. */
+ if (! e_fall)
+ continue;
+
+ /* If the fallthru block is still next, nothing to do. */
+ if (bb->aux == e_fall->dest)
+ continue;
+
+ /* A fallthru to exit block. */
+ if (e_fall->dest == EXIT_BLOCK_PTR)
+ continue;
+ }
+
+ /* We got here if we need to add a new jump insn.
+ Note force_nonfallthru can delete E_FALL and thus we have to
+ save E_FALL->src prior to the call to force_nonfallthru. */
+ src_bb = e_fall->src;
+ nb = force_nonfallthru_and_redirect (e_fall, e_fall->dest, ret_label);
+ if (nb)
+ {
+ nb->aux = bb->aux;
+ bb->aux = nb;
+ /* Don't process this new block. */
+ bb = nb;
+
+ /* Make sure new bb is tagged for correct section (same as
+ fall-thru source, since you cannot fall-thru across
+ section boundaries). */
+ BB_COPY_PARTITION (src_bb, single_pred (bb));
+ if (flag_reorder_blocks_and_partition
+ && targetm_common.have_named_sections
+ && JUMP_P (BB_END (bb))
+ && !any_condjump_p (BB_END (bb))
+ && (EDGE_SUCC (bb, 0)->flags & EDGE_CROSSING))
+ add_reg_note (BB_END (bb), REG_CROSSING_JUMP, NULL_RTX);
+ }
+ }
+
+ relink_block_chain (/*stay_in_cfglayout_mode=*/false);
+
+ /* Annoying special case - jump around dead jumptables left in the code. */
+ FOR_EACH_BB (bb)
+ {
+ edge e = find_fallthru_edge (bb->succs);
+
+ if (e && !can_fallthru (e->src, e->dest))
+ force_nonfallthru (e);
+ }
+
+ /* Ensure goto_locus from edges has some instructions with that locus
+ in RTL. */
+ if (!optimize)
+ FOR_EACH_BB (bb)
+ {
+ edge e;
+ edge_iterator ei;
+
+ FOR_EACH_EDGE (e, ei, bb->succs)
+ if (LOCATION_LOCUS (e->goto_locus) != UNKNOWN_LOCATION
+ && !(e->flags & EDGE_ABNORMAL))
+ {
+ edge e2;
+ edge_iterator ei2;
+ basic_block dest, nb;
+ rtx end;
+
+ insn = BB_END (e->src);
+ end = PREV_INSN (BB_HEAD (e->src));
+ while (insn != end
+ && (!NONDEBUG_INSN_P (insn) || !INSN_HAS_LOCATION (insn)))
+ insn = PREV_INSN (insn);
+ if (insn != end
+ && INSN_LOCATION (insn) == e->goto_locus)
+ continue;
+ if (simplejump_p (BB_END (e->src))
+ && !INSN_HAS_LOCATION (BB_END (e->src)))
+ {
+ INSN_LOCATION (BB_END (e->src)) = e->goto_locus;
+ continue;
+ }
+ dest = e->dest;
+ if (dest == EXIT_BLOCK_PTR)
+ {
+ /* Non-fallthru edges to the exit block cannot be split. */
+ if (!(e->flags & EDGE_FALLTHRU))
+ continue;
+ }
+ else
+ {
+ insn = BB_HEAD (dest);
+ end = NEXT_INSN (BB_END (dest));
+ while (insn != end && !NONDEBUG_INSN_P (insn))
+ insn = NEXT_INSN (insn);
+ if (insn != end && INSN_HAS_LOCATION (insn)
+ && INSN_LOCATION (insn) == e->goto_locus)
+ continue;
+ }
+ nb = split_edge (e);
+ if (!INSN_P (BB_END (nb)))
+ BB_END (nb) = emit_insn_after_noloc (gen_nop (), BB_END (nb),
+ nb);
+ INSN_LOCATION (BB_END (nb)) = e->goto_locus;
+
+ /* If there are other incoming edges to the destination block
+ with the same goto locus, redirect them to the new block as
+ well, this can prevent other such blocks from being created
+ in subsequent iterations of the loop. */
+ for (ei2 = ei_start (dest->preds); (e2 = ei_safe_edge (ei2)); )
+ if (LOCATION_LOCUS (e2->goto_locus) != UNKNOWN_LOCATION
+ && !(e2->flags & (EDGE_ABNORMAL | EDGE_FALLTHRU))
+ && e->goto_locus == e2->goto_locus)
+ redirect_edge_and_branch (e2, nb);
+ else
+ ei_next (&ei2);
+ }
+ }
+}
+\f
+/* Perform sanity checks on the insn chain.
+ 1. Check that next/prev pointers are consistent in both the forward and
+ reverse direction.
+ 2. Count insns in chain, going both directions, and check if equal.
+ 3. Check that get_last_insn () returns the actual end of chain. */
+
+DEBUG_FUNCTION void
+verify_insn_chain (void)
+{
+ rtx x, prevx, nextx;
+ int insn_cnt1, insn_cnt2;
+
+ for (prevx = NULL, insn_cnt1 = 1, x = get_insns ();
+ x != 0;
+ prevx = x, insn_cnt1++, x = NEXT_INSN (x))
+ gcc_assert (PREV_INSN (x) == prevx);
+
+ gcc_assert (prevx == get_last_insn ());
+
+ for (nextx = NULL, insn_cnt2 = 1, x = get_last_insn ();
+ x != 0;
+ nextx = x, insn_cnt2++, x = PREV_INSN (x))
+ gcc_assert (NEXT_INSN (x) == nextx);
+
+ gcc_assert (insn_cnt1 == insn_cnt2);
+}
+\f
+/* If we have assembler epilogues, the block falling through to exit must
+ be the last one in the reordered chain when we reach final. Ensure
+ that this condition is met. */
+static void
+fixup_fallthru_exit_predecessor (void)
+{
+ edge e;
+ basic_block bb = NULL;
+
+ /* This transformation is not valid before reload, because we might
+ separate a call from the instruction that copies the return
+ value. */
+ gcc_assert (reload_completed);
+
+ e = find_fallthru_edge (EXIT_BLOCK_PTR->preds);
+ if (e)
+ bb = e->src;
+
+ if (bb && bb->aux)
+ {
+ basic_block c = ENTRY_BLOCK_PTR->next_bb;
+
+ /* If the very first block is the one with the fall-through exit
+ edge, we have to split that block. */
+ if (c == bb)
+ {
+ bb = split_block (bb, NULL)->dest;
+ bb->aux = c->aux;
+ c->aux = bb;
+ BB_FOOTER (bb) = BB_FOOTER (c);
+ BB_FOOTER (c) = NULL;
+ }
+
+ while (c->aux != bb)
+ c = (basic_block) c->aux;
+
+ c->aux = bb->aux;
+ while (c->aux)
+ c = (basic_block) c->aux;
+
+ c->aux = bb;
+ bb->aux = NULL;
+ }
+}
+
+/* In case there are more than one fallthru predecessors of exit, force that
+ there is only one. */
+
+static void
+force_one_exit_fallthru (void)
+{
+ edge e, predecessor = NULL;
+ bool more = false;
+ edge_iterator ei;
+ basic_block forwarder, bb;
+
+ FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
+ if (e->flags & EDGE_FALLTHRU)
+ {
+ if (predecessor == NULL)
+ predecessor = e;
+ else
+ {
+ more = true;
+ break;
+ }
+ }
+
+ if (!more)
+ return;
+
+ /* Exit has several fallthru predecessors. Create a forwarder block for
+ them. */
+ forwarder = split_edge (predecessor);
+ for (ei = ei_start (EXIT_BLOCK_PTR->preds); (e = ei_safe_edge (ei)); )
+ {
+ if (e->src == forwarder
+ || !(e->flags & EDGE_FALLTHRU))
+ ei_next (&ei);
+ else
+ redirect_edge_and_branch_force (e, forwarder);
+ }
+
+ /* Fix up the chain of blocks -- make FORWARDER immediately precede the
+ exit block. */
+ FOR_EACH_BB (bb)
+ {
+ if (bb->aux == NULL && bb != forwarder)
+ {
+ bb->aux = forwarder;
+ break;
+ }
+ }
+}
+\f
+/* Return true in case it is possible to duplicate the basic block BB. */
+
+static bool
+cfg_layout_can_duplicate_bb_p (const_basic_block bb)
+{
+ /* Do not attempt to duplicate tablejumps, as we need to unshare
+ the dispatch table. This is difficult to do, as the instructions
+ computing jump destination may be hoisted outside the basic block. */
+ if (tablejump_p (BB_END (bb), NULL, NULL))
+ return false;
+
+ /* Do not duplicate blocks containing insns that can't be copied. */
+ if (targetm.cannot_copy_insn_p)
+ {
+ rtx insn = BB_HEAD (bb);
+ while (1)
+ {
+ if (INSN_P (insn) && targetm.cannot_copy_insn_p (insn))
+ return false;
+ if (insn == BB_END (bb))
+ break;
+ insn = NEXT_INSN (insn);
+ }
+ }
+
+ return true;
+}
+
+rtx
+duplicate_insn_chain (rtx from, rtx to)
+{
+ rtx insn, last, copy;
+
+ /* Avoid updating of boundaries of previous basic block. The
+ note will get removed from insn stream in fixup. */
+ last = emit_note (NOTE_INSN_DELETED);
+
+ /* Create copy at the end of INSN chain. The chain will
+ be reordered later. */
+ for (insn = from; insn != NEXT_INSN (to); insn = NEXT_INSN (insn))
+ {
+ switch (GET_CODE (insn))
+ {
+ case DEBUG_INSN:
+ /* Don't duplicate label debug insns. */
+ if (TREE_CODE (INSN_VAR_LOCATION_DECL (insn)) == LABEL_DECL)
+ break;
+ /* FALLTHRU */
+ case INSN:
+ case CALL_INSN:
+ case JUMP_INSN:
+ /* Avoid copying of dispatch tables. We never duplicate
+ tablejumps, so this can hit only in case the table got
+ moved far from original jump. */
+ if (GET_CODE (PATTERN (insn)) == ADDR_VEC
+ || GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC)
+ {
+ /* Avoid copying following barrier as well if any
+ (and debug insns in between). */
+ rtx next;
+
+ for (next = NEXT_INSN (insn);
+ next != NEXT_INSN (to);
+ next = NEXT_INSN (next))
+ if (!DEBUG_INSN_P (next))
+ break;
+ if (next != NEXT_INSN (to) && BARRIER_P (next))
+ insn = next;
+ break;
+ }
+ copy = emit_copy_of_insn_after (insn, get_last_insn ());
+ if (JUMP_P (insn) && JUMP_LABEL (insn) != NULL_RTX
+ && ANY_RETURN_P (JUMP_LABEL (insn)))
+ JUMP_LABEL (copy) = JUMP_LABEL (insn);
+ maybe_copy_prologue_epilogue_insn (insn, copy);
+ break;
+
+ case CODE_LABEL:
+ break;
+
+ case BARRIER:
+ emit_barrier ();
+ break;
+
+ case NOTE:
+ switch (NOTE_KIND (insn))
+ {
+ /* In case prologue is empty and function contain label
+ in first BB, we may want to copy the block. */
+ case NOTE_INSN_PROLOGUE_END:
+
+ case NOTE_INSN_DELETED:
+ case NOTE_INSN_DELETED_LABEL:
+ case NOTE_INSN_DELETED_DEBUG_LABEL:
+ /* No problem to strip these. */
+ case NOTE_INSN_FUNCTION_BEG:
+ /* There is always just single entry to function. */
+ case NOTE_INSN_BASIC_BLOCK:
+ break;
+
+ case NOTE_INSN_EPILOGUE_BEG:
+ case NOTE_INSN_SWITCH_TEXT_SECTIONS:
+ emit_note_copy (insn);
+ break;
+
+ default:
+ /* All other notes should have already been eliminated. */
+ gcc_unreachable ();
+ }
+ break;
+ default:
+ gcc_unreachable ();
+ }
+ }
+ insn = NEXT_INSN (last);
+ delete_insn (last);
+ return insn;
+}
+
+/* Create a duplicate of the basic block BB. */
+
+static basic_block
+cfg_layout_duplicate_bb (basic_block bb)
+{
+ rtx insn;
+ basic_block new_bb;
+
+ insn = duplicate_insn_chain (BB_HEAD (bb), BB_END (bb));
+ new_bb = create_basic_block (insn,
+ insn ? get_last_insn () : NULL,
+ EXIT_BLOCK_PTR->prev_bb);
+
+ BB_COPY_PARTITION (new_bb, bb);
+ if (BB_HEADER (bb))
+ {
+ insn = BB_HEADER (bb);
+ while (NEXT_INSN (insn))
+ insn = NEXT_INSN (insn);
+ insn = duplicate_insn_chain (BB_HEADER (bb), insn);
+ if (insn)
+ BB_HEADER (new_bb) = unlink_insn_chain (insn, get_last_insn ());
+ }
+
+ if (BB_FOOTER (bb))
+ {
+ insn = BB_FOOTER (bb);
+ while (NEXT_INSN (insn))
+ insn = NEXT_INSN (insn);
+ insn = duplicate_insn_chain (BB_FOOTER (bb), insn);
+ if (insn)
+ BB_FOOTER (new_bb) = unlink_insn_chain (insn, get_last_insn ());
+ }
+
+ return new_bb;
+}
+
+\f
+/* Main entry point to this module - initialize the datastructures for
+ CFG layout changes. It keeps LOOPS up-to-date if not null.
+
+ FLAGS is a set of additional flags to pass to cleanup_cfg(). */
+
+void
+cfg_layout_initialize (unsigned int flags)
+{
+ rtx x;
+ basic_block bb;
+
+ initialize_original_copy_tables ();
+
+ cfg_layout_rtl_register_cfg_hooks ();
+
+ record_effective_endpoints ();
+
+ /* Make sure that the targets of non local gotos are marked. */
+ for (x = nonlocal_goto_handler_labels; x; x = XEXP (x, 1))
+ {
+ bb = BLOCK_FOR_INSN (XEXP (x, 0));
+ bb->flags |= BB_NON_LOCAL_GOTO_TARGET;
+ }
+
+ cleanup_cfg (CLEANUP_CFGLAYOUT | flags);
+}
+
+/* Splits superblocks. */
+void
+break_superblocks (void)
+{
+ sbitmap superblocks;
+ bool need = false;
+ basic_block bb;
+
+ superblocks = sbitmap_alloc (last_basic_block);
+ bitmap_clear (superblocks);
+
+ FOR_EACH_BB (bb)
+ if (bb->flags & BB_SUPERBLOCK)
+ {
+ bb->flags &= ~BB_SUPERBLOCK;
+ bitmap_set_bit (superblocks, bb->index);
+ need = true;
+ }
+
+ if (need)
+ {
+ rebuild_jump_labels (get_insns ());
+ find_many_sub_basic_blocks (superblocks);
+ }
+
+ free (superblocks);
+}
+
+/* Finalize the changes: reorder insn list according to the sequence specified
+ by aux pointers, enter compensation code, rebuild scope forest. */
+
+void
+cfg_layout_finalize (void)
+{
+#ifdef ENABLE_CHECKING
+ verify_flow_info ();
+#endif
+ force_one_exit_fallthru ();
+ rtl_register_cfg_hooks ();
+ if (reload_completed
+#ifdef HAVE_epilogue
+ && !HAVE_epilogue
+#endif
+ )
+ fixup_fallthru_exit_predecessor ();
+ fixup_reorder_chain ();
+
+ rebuild_jump_labels (get_insns ());
+ delete_dead_jumptables ();
+
+#ifdef ENABLE_CHECKING
+ verify_insn_chain ();
+ verify_flow_info ();
+#endif
+}
+
+
+/* Same as split_block but update cfg_layout structures. */
+
+static basic_block
+cfg_layout_split_block (basic_block bb, void *insnp)
+{
+ rtx insn = (rtx) insnp;
+ basic_block new_bb = rtl_split_block (bb, insn);
+
+ BB_FOOTER (new_bb) = BB_FOOTER (bb);
+ BB_FOOTER (bb) = NULL;
+
+ return new_bb;
+}
+
+/* Redirect Edge to DEST. */
+static edge
+cfg_layout_redirect_edge_and_branch (edge e, basic_block dest)
+{
+ basic_block src = e->src;
+ edge ret;
+
+ if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH))
+ return NULL;
+
+ if (e->dest == dest)
+ return e;
+
+ if (e->src != ENTRY_BLOCK_PTR
+ && (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_HEADER (bb))
{
next = BB_HEAD (bb);
if (prev)
- NEXT_INSN (prev) = bb->il.rtl->header;
+ NEXT_INSN (prev) = BB_HEADER (bb);
else
- set_first_insn (bb->il.rtl->header);
- PREV_INSN (bb->il.rtl->header) = prev;
- insn = bb->il.rtl->header;
+ set_first_insn (BB_HEADER (bb));
+ PREV_INSN (BB_HEADER (bb)) = prev;
+ insn = BB_HEADER (bb);
while (NEXT_INSN (insn))
insn = NEXT_INSN (insn);
NEXT_INSN (insn) = next;
PREV_INSN (next) = insn;
}
next = NEXT_INSN (BB_END (bb));
- if (bb->il.rtl->footer)
+ if (BB_FOOTER (bb))
{
- insn = bb->il.rtl->footer;
+ insn = BB_FOOTER (bb);
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);
+ BB_FOOTER (bb) = NEXT_INSN (insn);
if (NEXT_INSN (insn))
PREV_INSN (NEXT_INSN (insn)) = PREV_INSN (insn);
}
break;
insn = NEXT_INSN (insn);
}
- if (bb->il.rtl->footer)
+ if (BB_FOOTER (bb))
{
insn = BB_END (bb);
- NEXT_INSN (insn) = bb->il.rtl->footer;
- PREV_INSN (bb->il.rtl->footer) = insn;
+ NEXT_INSN (insn) = BB_FOOTER (bb);
+ PREV_INSN (BB_FOOTER (bb)) = insn;
while (NEXT_INSN (insn))
insn = NEXT_INSN (insn);
NEXT_INSN (insn) = next;
}
}
if (bb->next_bb != EXIT_BLOCK_PTR)
- to = &bb->next_bb->il.rtl->header;
+ to = &BB_HEADER (bb->next_bb);
else
to = &cfg_layout_function_footer;
if (BB_PARTITION (a) != BB_PARTITION (b))
return false;
+ /* Protect the loop latches. */
+ if (current_loops && b->loop_father->latch == b)
+ return false;
+
+ /* If we would end up moving B's instructions, make sure it doesn't fall
+ through into the exit block, since we cannot recover from a fallthrough
+ edge into the exit block occurring in the middle of a function. */
+ if (NEXT_INSN (BB_END (a)) != BB_HEAD (b))
+ {
+ edge e = find_fallthru_edge (b->succs);
+ if (e && e->dest == EXIT_BLOCK_PTR)
+ return false;
+ }
+
/* There must be exactly one edge in between the blocks. */
return (single_succ_p (a)
&& single_succ (a) == b
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;
+ rtx insn;
+
+ gcc_checking_assert (cfg_layout_can_merge_blocks_p (a, b));
if (dump_file)
- fprintf (dump_file, "merging block %d into block %d\n", b->index, a->index);
+ 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 CFG and the edge is the only place in RTL which holds
+ some unique locus, emit a nop with that locus in between. */
+ if (!optimize)
+ emit_nop_for_unique_locus_between (a, b);
+
/* Possible line number notes should appear in between. */
- if (b->il.rtl->header)
+ if (BB_HEADER (b))
{
rtx first = BB_END (a), last;
- last = emit_insn_after_noloc (b->il.rtl->header, BB_END (a), a);
+ last = emit_insn_after_noloc (BB_HEADER (b), 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;
+ BB_HEADER (b) = 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));
+ insn = 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;
- delete_insn (first);
+ emit_insn_after_noloc (insn, BB_END (a), a);
}
/* Otherwise just re-associate the instructions. */
else
{
- rtx insn;
-
- for (insn = BB_HEAD (b);
- insn != NEXT_INSN (BB_END (b));
- insn = NEXT_INSN (insn))
- {
- set_block_for_insn (insn, a);
- df_insn_change_bb (insn);
- }
-
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);
}
+ /* emit_insn_after_noloc doesn't call df_insn_change_bb.
+ We need to explicitly call. */
+ update_bb_for_insn_chain (insn, BB_END (b), a);
+
+ /* Skip possible DELETED_LABEL insn. */
+ if (!NOTE_INSN_BASIC_BLOCK_P (insn))
+ insn = NEXT_INSN (insn);
+ gcc_assert (NOTE_INSN_BASIC_BLOCK_P (insn));
+ BB_HEAD (b) = NULL;
+ delete_insn (insn);
+
df_bb_delete (b->index);
/* Possible tablejumps and barriers should appear after the block. */
- if (b->il.rtl->footer)
+ if (BB_FOOTER (b))
{
- if (!a->il.rtl->footer)
- a->il.rtl->footer = b->il.rtl->footer;
+ if (!BB_FOOTER (a))
+ BB_FOOTER (a) = BB_FOOTER (b);
else
{
- rtx last = a->il.rtl->footer;
+ rtx last = BB_FOOTER (a);
while (NEXT_INSN (last))
last = NEXT_INSN (last);
- NEXT_INSN (last) = b->il.rtl->footer;
- PREV_INSN (b->il.rtl->footer) = last;
+ NEXT_INSN (last) = BB_FOOTER (b);
+ PREV_INSN (BB_FOOTER (b)) = last;
}
- b->il.rtl->footer = NULL;
+ BB_FOOTER (b) = NULL;
}
+ /* If B was a forwarder block, propagate the locus on the edge. */
+ if (forwarder_p
+ && LOCATION_LOCUS (EDGE_SUCC (b, 0)->goto_locus) != UNKNOWN_LOCATION)
+ EDGE_SUCC (b, 0)->goto_locus = EDGE_SUCC (a, 0)->goto_locus;
+
if (dump_file)
- fprintf (dump_file, "Merged blocks %d and %d.\n",
- a->index, b->index);
+ 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);
+ 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 true if BB contains only labels or non-executable
+ instructions. */
+
+static bool
+rtl_block_empty_p (basic_block bb)
+{
+ rtx insn;
+
+ if (bb == ENTRY_BLOCK_PTR || bb == EXIT_BLOCK_PTR)
+ return true;
+
+ FOR_BB_INSNS (bb, insn)
+ if (NONDEBUG_INSN_P (insn) && !any_uncondjump_p (insn))
+ return false;
+
+ return true;
+}
+
+/* Split a basic block if it ends with a conditional branch and if
+ the other part of the block is not empty. */
+
+static basic_block
+rtl_split_block_before_cond_jump (basic_block bb)
+{
+ rtx insn;
+ rtx split_point = NULL;
+ rtx last = NULL;
+ bool found_code = false;
+
+ FOR_BB_INSNS (bb, insn)
+ {
+ if (any_condjump_p (insn))
+ split_point = last;
+ else if (NONDEBUG_INSN_P (insn))
+ found_code = true;
+ last = insn;
+ }
+
+ /* Did not find everything. */
+ if (found_code && split_point)
+ return split_block (bb, split_point)->dest;
+ else
+ return NULL;
+}
+
/* Return 1 if BB ends with a call, possibly followed by some
instructions that must stay with the call, 0 otherwise. */
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));
}
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
if (! blocks)
check_last_block = true;
else
- check_last_block = TEST_BIT (blocks, EXIT_BLOCK_PTR->prev_bb->index);
+ check_last_block = bitmap_bit_p (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
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 ();
}
}
if (!bb)
continue;
- if (blocks && !TEST_BIT (blocks, i))
+ if (blocks && !bitmap_bit_p (blocks, i))
continue;
for (insn = BB_END (bb); ; insn = prev_insn)
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)++;
void
init_rtl_bb_info (basic_block bb)
{
- gcc_assert (!bb->il.rtl);
- bb->il.rtl = GGC_CNEW (struct rtl_bb_info);
-}
-
-
-/* Add EXPR to the end of basic block BB. */
-
-rtx
-insert_insn_end_bb_new (rtx pat, basic_block bb)
-{
- 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);
-
- /* 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);
-
-#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, bb);
- }
-
- /* 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. */
-
- /* 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 we found all the parameter loads, then we want to insert
- before the first parameter load.
-
- 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);
-
- new_insn = emit_insn_before_noloc (pat, insn, bb);
- }
- else
- new_insn = emit_insn_after_noloc (pat, insn, bb);
-
- return new_insn;
+ gcc_assert (!bb->il.x.rtl);
+ bb->il.x.head_ = NULL;
+ bb->il.x.rtl = ggc_alloc_cleared_rtl_bb_info ();
}
/* Returns true if it is possible to remove edge E by redirecting
return true;
}
+static basic_block
+rtl_duplicate_bb (basic_block bb)
+{
+ bb = cfg_layout_duplicate_bb (bb);
+ bb->aux = NULL;
+ return bb;
+}
+
+/* Do book-keeping of basic block BB for the profile consistency checker.
+ If AFTER_PASS is 0, do pre-pass accounting, or if AFTER_PASS is 1
+ then do post-pass accounting. Store the counting in RECORD. */
+static void
+rtl_account_profile_record (basic_block bb, int after_pass,
+ struct profile_record *record)
+{
+ rtx insn;
+ FOR_BB_INSNS (bb, insn)
+ if (INSN_P (insn))
+ {
+ record->size[after_pass]
+ += insn_rtx_cost (PATTERN (insn), false);
+ if (profile_status == PROFILE_READ)
+ record->time[after_pass]
+ += insn_rtx_cost (PATTERN (insn), true) * bb->count;
+ else if (profile_status == PROFILE_GUESSED)
+ record->time[after_pass]
+ += insn_rtx_cost (PATTERN (insn), true) * bb->frequency;
+ }
+}
+
/* Implementation of CFG manipulation for linearized RTL. */
struct cfg_hooks rtl_cfg_hooks = {
"rtl",
rtl_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 */
+ rtl_block_empty_p, /* block_empty_p */
+ rtl_split_block_before_cond_jump, /* split_block_before_cond_jump */
+ rtl_account_profile_record,
};
/* Implementation of CFG manipulation for cfg layout RTL, where
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,
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 */
+ rtl_block_empty_p, /* block_empty_p */
+ rtl_split_block_before_cond_jump, /* split_block_before_cond_jump */
+ rtl_account_profile_record,
};
+
+#include "gt-cfgrtl.h"
projects / platform / upstream / gcc.git / blobdiff