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diff --git a/gcc-4.2.1-5666.3/gcc/cfgbuild.c b/gcc-4.2.1-5666.3/gcc/cfgbuild.c
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+/* Control flow graph building code for GNU compiler.
+ Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
+ 1999, 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 2, or (at your option) any later
+version.
+
+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with GCC; see the file COPYING. If not, write to the Free
+Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301, USA. */
+
+/* find_basic_blocks divides the current function's rtl into basic
+ blocks and constructs the CFG. The blocks are recorded in the
+ basic_block_info array; the CFG exists in the edge structures
+ referenced by the blocks.
+
+ find_basic_blocks also finds any unreachable loops and deletes them.
+
+ Available functionality:
+ - CFG construction
+ find_basic_blocks */
+
+#include "config.h"
+#include "system.h"
+#include "coretypes.h"
+#include "tm.h"
+#include "tree.h"
+#include "rtl.h"
+#include "hard-reg-set.h"
+#include "basic-block.h"
+#include "regs.h"
+#include "flags.h"
+#include "output.h"
+#include "function.h"
+#include "except.h"
+#include "toplev.h"
+#include "timevar.h"
+
+static int count_basic_blocks (rtx);
+static void find_basic_blocks_1 (rtx);
+static void make_edges (basic_block, basic_block, int);
+static void make_label_edge (sbitmap, basic_block, rtx, int);
+static void find_bb_boundaries (basic_block);
+static void compute_outgoing_frequencies (basic_block);
+
+/* Return true if insn is something that should be contained inside basic
+ block. */
+
+bool
+inside_basic_block_p (rtx insn)
+{
+ switch (GET_CODE (insn))
+ {
+ case CODE_LABEL:
+ /* Avoid creating of basic block for jumptables. */
+ return (NEXT_INSN (insn) == 0
+ || !JUMP_P (NEXT_INSN (insn))
+ || (GET_CODE (PATTERN (NEXT_INSN (insn))) != ADDR_VEC
+ && GET_CODE (PATTERN (NEXT_INSN (insn))) != ADDR_DIFF_VEC));
+
+ case JUMP_INSN:
+ return (GET_CODE (PATTERN (insn)) != ADDR_VEC
+ && GET_CODE (PATTERN (insn)) != ADDR_DIFF_VEC);
+
+ case CALL_INSN:
+ case INSN:
+ return true;
+
+ case BARRIER:
+ case NOTE:
+ return false;
+
+ default:
+ gcc_unreachable ();
+ }
+}
+
+/* Return true if INSN may cause control flow transfer, so it should be last in
+ the basic block. */
+
+bool
+control_flow_insn_p (rtx insn)
+{
+ rtx note;
+
+ switch (GET_CODE (insn))
+ {
+ case NOTE:
+ case CODE_LABEL:
+ return false;
+
+ case JUMP_INSN:
+ /* Jump insn always causes control transfer except for tablejumps. */
+ return (GET_CODE (PATTERN (insn)) != ADDR_VEC
+ && GET_CODE (PATTERN (insn)) != ADDR_DIFF_VEC);
+
+ case CALL_INSN:
+ /* Noreturn and sibling call instructions terminate the basic blocks
+ (but only if they happen unconditionally). */
+ if ((SIBLING_CALL_P (insn)
+ || find_reg_note (insn, REG_NORETURN, 0))
+ && GET_CODE (PATTERN (insn)) != COND_EXEC)
+ return true;
+ /* Call insn may return to the nonlocal goto handler. */
+ return ((nonlocal_goto_handler_labels
+ && (0 == (note = find_reg_note (insn, REG_EH_REGION,
+ NULL_RTX))
+ || INTVAL (XEXP (note, 0)) >= 0))
+ /* Or may trap. */
+ || can_throw_internal (insn));
+
+ case INSN:
+ /* APPLE LOCAL begin deletion 6258941 */
+ /* APPLE LOCAL end deletion 6258941 */
+ return (flag_non_call_exceptions && can_throw_internal (insn));
+
+ case BARRIER:
+ /* It is nonsense to reach barrier when looking for the
+ end of basic block, but before dead code is eliminated
+ this may happen. */
+ return false;
+
+ default:
+ gcc_unreachable ();
+ }
+}
+
+/* Count the basic blocks of the function. */
+
+static int
+count_basic_blocks (rtx f)
+{
+ int count = NUM_FIXED_BLOCKS;
+ bool saw_insn = false;
+ rtx insn;
+
+ for (insn = f; insn; insn = NEXT_INSN (insn))
+ {
+ /* Code labels and barriers causes current basic block to be
+ terminated at previous real insn. */
+ if ((LABEL_P (insn) || BARRIER_P (insn))
+ && saw_insn)
+ count++, saw_insn = false;
+
+ /* Start basic block if needed. */
+ if (!saw_insn && inside_basic_block_p (insn))
+ saw_insn = true;
+
+ /* Control flow insn causes current basic block to be terminated. */
+ if (saw_insn && control_flow_insn_p (insn))
+ count++, saw_insn = false;
+ }
+
+ if (saw_insn)
+ count++;
+
+ /* The rest of the compiler works a bit smoother when we don't have to
+ check for the edge case of do-nothing functions with no basic blocks. */
+ if (count == NUM_FIXED_BLOCKS)
+ {
+ emit_insn (gen_rtx_USE (VOIDmode, const0_rtx));
+ count = NUM_FIXED_BLOCKS + 1;
+ }
+
+ return count;
+}
+
+/* Create an edge between two basic blocks. FLAGS are auxiliary information
+ about the edge that is accumulated between calls. */
+
+/* Create an edge from a basic block to a label. */
+
+static void
+make_label_edge (sbitmap edge_cache, basic_block src, rtx label, int flags)
+{
+ gcc_assert (LABEL_P (label));
+
+ /* If the label was never emitted, this insn is junk, but avoid a
+ crash trying to refer to BLOCK_FOR_INSN (label). This can happen
+ as a result of a syntax error and a diagnostic has already been
+ printed. */
+
+ if (INSN_UID (label) == 0)
+ return;
+
+ cached_make_edge (edge_cache, src, BLOCK_FOR_INSN (label), flags);
+}
+
+/* Create the edges generated by INSN in REGION. */
+
+void
+rtl_make_eh_edge (sbitmap edge_cache, basic_block src, rtx insn)
+{
+ int is_call = CALL_P (insn) ? EDGE_ABNORMAL_CALL : 0;
+ rtx handlers, i;
+
+ handlers = reachable_handlers (insn);
+
+ for (i = handlers; i; i = XEXP (i, 1))
+ make_label_edge (edge_cache, src, XEXP (i, 0),
+ EDGE_ABNORMAL | EDGE_EH | is_call);
+
+ free_INSN_LIST_list (&handlers);
+}
+
+/* States of basic block as seen by find_many_sub_basic_blocks. */
+enum state {
+ /* Basic blocks created via split_block belong to this state.
+ make_edges will examine these basic blocks to see if we need to
+ create edges going out of them. */
+ BLOCK_NEW = 0,
+
+ /* Basic blocks that do not need examining belong to this state.
+ These blocks will be left intact. In particular, make_edges will
+ not create edges going out of these basic blocks. */
+ BLOCK_ORIGINAL,
+
+ /* Basic blocks that may need splitting (due to a label appearing in
+ the middle, etc) belong to this state. After splitting them,
+ make_edges will create edges going out of them as needed. */
+ BLOCK_TO_SPLIT
+};
+
+#define STATE(BB) (enum state) ((size_t) (BB)->aux)
+#define SET_STATE(BB, STATE) ((BB)->aux = (void *) (size_t) (STATE))
+
+/* Used internally by purge_dead_tablejump_edges, ORed into state. */
+#define BLOCK_USED_BY_TABLEJUMP 32
+#define FULL_STATE(BB) ((size_t) (BB)->aux)
+
+/* Identify the edges going out of basic blocks between MIN and MAX,
+ inclusive, that have their states set to BLOCK_NEW or
+ BLOCK_TO_SPLIT.
+
+ UPDATE_P should be nonzero if we are updating CFG and zero if we
+ are building CFG from scratch. */
+
+static void
+make_edges (basic_block min, basic_block max, int update_p)
+{
+ basic_block bb;
+ sbitmap edge_cache = NULL;
+
+ /* Heavy use of computed goto in machine-generated code can lead to
+ nearly fully-connected CFGs. In that case we spend a significant
+ amount of time searching the edge lists for duplicates. */
+ if (forced_labels || cfun->max_jumptable_ents > 100)
+ edge_cache = sbitmap_alloc (last_basic_block);
+
+ /* By nature of the way these get numbered, ENTRY_BLOCK_PTR->next_bb block
+ is always the entry. */
+ if (min == ENTRY_BLOCK_PTR->next_bb)
+ make_edge (ENTRY_BLOCK_PTR, min, EDGE_FALLTHRU);
+
+ FOR_BB_BETWEEN (bb, min, max->next_bb, next_bb)
+ {
+ rtx insn, x;
+ enum rtx_code code;
+ edge e;
+ edge_iterator ei;
+
+ if (STATE (bb) == BLOCK_ORIGINAL)
+ continue;
+
+ /* If we have an edge cache, cache edges going out of BB. */
+ if (edge_cache)
+ {
+ sbitmap_zero (edge_cache);
+ if (update_p)
+ {
+ FOR_EACH_EDGE (e, ei, bb->succs)
+ if (e->dest != EXIT_BLOCK_PTR)
+ SET_BIT (edge_cache, e->dest->index);
+ }
+ }
+
+ if (LABEL_P (BB_HEAD (bb))
+ && LABEL_ALT_ENTRY_P (BB_HEAD (bb)))
+ cached_make_edge (NULL, ENTRY_BLOCK_PTR, bb, 0);
+
+ /* Examine the last instruction of the block, and discover the
+ ways we can leave the block. */
+
+ insn = BB_END (bb);
+ code = GET_CODE (insn);
+
+ /* A branch. */
+ if (code == JUMP_INSN)
+ {
+ rtx tmp;
+
+ /* Recognize exception handling placeholders. */
+ if (GET_CODE (PATTERN (insn)) == RESX)
+ rtl_make_eh_edge (edge_cache, bb, insn);
+
+ /* Recognize a non-local goto as a branch outside the
+ current function. */
+ else if (find_reg_note (insn, REG_NON_LOCAL_GOTO, NULL_RTX))
+ ;
+
+ /* Recognize a tablejump and do the right thing. */
+ else if (tablejump_p (insn, NULL, &tmp))
+ {
+ rtvec vec;
+ int j;
+
+ if (GET_CODE (PATTERN (tmp)) == ADDR_VEC)
+ vec = XVEC (PATTERN (tmp), 0);
+ else
+ vec = XVEC (PATTERN (tmp), 1);
+
+ for (j = GET_NUM_ELEM (vec) - 1; j >= 0; --j)
+ make_label_edge (edge_cache, bb,
+ XEXP (RTVEC_ELT (vec, j), 0), 0);
+
+ /* Some targets (eg, ARM) emit a conditional jump that also
+ contains the out-of-range target. Scan for these and
+ add an edge if necessary. */
+ if ((tmp = single_set (insn)) != NULL
+ && SET_DEST (tmp) == pc_rtx
+ && GET_CODE (SET_SRC (tmp)) == IF_THEN_ELSE
+ && GET_CODE (XEXP (SET_SRC (tmp), 2)) == LABEL_REF)
+ make_label_edge (edge_cache, bb,
+ XEXP (XEXP (SET_SRC (tmp), 2), 0), 0);
+ }
+
+ /* If this is a computed jump, then mark it as reaching
+ everything on the forced_labels list. */
+ else if (computed_jump_p (insn))
+ {
+ for (x = forced_labels; x; x = XEXP (x, 1))
+ make_label_edge (edge_cache, bb, XEXP (x, 0), EDGE_ABNORMAL);
+ }
+
+ /* Returns create an exit out. */
+ else if (returnjump_p (insn))
+ cached_make_edge (edge_cache, bb, EXIT_BLOCK_PTR, 0);
+
+ /* Otherwise, we have a plain conditional or unconditional jump. */
+ else
+ {
+ gcc_assert (JUMP_LABEL (insn));
+ make_label_edge (edge_cache, bb, JUMP_LABEL (insn), 0);
+ }
+ }
+
+ /* If this is a sibling call insn, then this is in effect a combined call
+ and return, and so we need an edge to the exit block. No need to
+ worry about EH edges, since we wouldn't have created the sibling call
+ in the first place. */
+ if (code == CALL_INSN && SIBLING_CALL_P (insn))
+ cached_make_edge (edge_cache, bb, EXIT_BLOCK_PTR,
+ EDGE_SIBCALL | EDGE_ABNORMAL);
+
+ /* If this is a CALL_INSN, then mark it as reaching the active EH
+ handler for this CALL_INSN. If we're handling non-call
+ exceptions then any insn can reach any of the active handlers.
+ Also mark the CALL_INSN as reaching any nonlocal goto handler. */
+ else if (code == CALL_INSN || flag_non_call_exceptions)
+ {
+ /* Add any appropriate EH edges. */
+ rtl_make_eh_edge (edge_cache, bb, insn);
+
+ if (code == CALL_INSN && nonlocal_goto_handler_labels)
+ {
+ /* ??? This could be made smarter: in some cases it's possible
+ to tell that certain calls will not do a nonlocal goto.
+ For example, if the nested functions that do the nonlocal
+ gotos do not have their addresses taken, then only calls to
+ those functions or to other nested functions that use them
+ could possibly do nonlocal gotos. */
+
+ /* We do know that a REG_EH_REGION note with a value less
+ than 0 is guaranteed not to perform a non-local goto. */
+ rtx note = find_reg_note (insn, REG_EH_REGION, NULL_RTX);
+
+ if (!note || INTVAL (XEXP (note, 0)) >= 0)
+ for (x = nonlocal_goto_handler_labels; x; x = XEXP (x, 1))
+ make_label_edge (edge_cache, bb, XEXP (x, 0),
+ EDGE_ABNORMAL | EDGE_ABNORMAL_CALL);
+ }
+ }
+
+ /* Find out if we can drop through to the next block. */
+ insn = NEXT_INSN (insn);
+ e = find_edge (bb, EXIT_BLOCK_PTR);
+ if (e && e->flags & EDGE_FALLTHRU)
+ insn = NULL;
+
+ while (insn
+ && NOTE_P (insn)
+ && NOTE_LINE_NUMBER (insn) != NOTE_INSN_BASIC_BLOCK)
+ insn = NEXT_INSN (insn);
+
+ if (!insn)
+ cached_make_edge (edge_cache, bb, EXIT_BLOCK_PTR, EDGE_FALLTHRU);
+ else if (bb->next_bb != EXIT_BLOCK_PTR)
+ {
+ if (insn == BB_HEAD (bb->next_bb))
+ cached_make_edge (edge_cache, bb, bb->next_bb, EDGE_FALLTHRU);
+ }
+ }
+
+ if (edge_cache)
+ sbitmap_vector_free (edge_cache);
+}
+
+/* Find all basic blocks of the function whose first insn is F.
+
+ Collect and return a list of labels whose addresses are taken. This
+ will be used in make_edges for use with computed gotos. */
+
+static void
+find_basic_blocks_1 (rtx f)
+{
+ rtx insn, next;
+ rtx bb_note = NULL_RTX;
+ rtx head = NULL_RTX;
+ rtx end = NULL_RTX;
+ basic_block prev = ENTRY_BLOCK_PTR;
+
+ /* We process the instructions in a slightly different way than we did
+ previously. This is so that we see a NOTE_BASIC_BLOCK after we have
+ closed out the previous block, so that it gets attached at the proper
+ place. Since this form should be equivalent to the previous,
+ count_basic_blocks continues to use the old form as a check. */
+
+ for (insn = f; insn; insn = next)
+ {
+ enum rtx_code code = GET_CODE (insn);
+
+ next = NEXT_INSN (insn);
+
+ if ((LABEL_P (insn) || BARRIER_P (insn))
+ && head)
+ {
+ prev = create_basic_block_structure (head, end, bb_note, prev);
+ head = end = NULL_RTX;
+ bb_note = NULL_RTX;
+ }
+
+ if (inside_basic_block_p (insn))
+ {
+ if (head == NULL_RTX)
+ head = insn;
+ end = insn;
+ }
+
+ if (head && control_flow_insn_p (insn))
+ {
+ prev = create_basic_block_structure (head, end, bb_note, prev);
+ head = end = NULL_RTX;
+ bb_note = NULL_RTX;
+ }
+
+ switch (code)
+ {
+ case NOTE:
+ {
+ int kind = NOTE_LINE_NUMBER (insn);
+
+ /* Look for basic block notes with which to keep the
+ basic_block_info pointers stable. Unthread the note now;
+ we'll put it back at the right place in create_basic_block.
+ Or not at all if we've already found a note in this block. */
+ if (kind == NOTE_INSN_BASIC_BLOCK)
+ {
+ if (bb_note == NULL_RTX)
+ bb_note = insn;
+ else
+ next = delete_insn (insn);
+ }
+ break;
+ }
+
+ case CODE_LABEL:
+ case JUMP_INSN:
+ case CALL_INSN:
+ case INSN:
+ case BARRIER:
+ break;
+
+ default:
+ gcc_unreachable ();
+ }
+ }
+
+ if (head != NULL_RTX)
+ create_basic_block_structure (head, end, bb_note, prev);
+ else if (bb_note)
+ delete_insn (bb_note);
+
+ gcc_assert (last_basic_block == n_basic_blocks);
+
+ clear_aux_for_blocks ();
+}
+
+
+/* Find basic blocks of the current function.
+ F is the first insn of the function. */
+
+void
+find_basic_blocks (rtx f)
+{
+ basic_block bb;
+
+ timevar_push (TV_CFG);
+
+ /* Flush out existing data. */
+ if (basic_block_info != NULL)
+ {
+ clear_edges ();
+
+ /* Clear bb->aux on all extant basic blocks. We'll use this as a
+ tag for reuse during create_basic_block, just in case some pass
+ copies around basic block notes improperly. */
+ FOR_EACH_BB (bb)
+ bb->aux = NULL;
+
+ basic_block_info = NULL;
+ }
+
+ n_basic_blocks = count_basic_blocks (f);
+ last_basic_block = NUM_FIXED_BLOCKS;
+ ENTRY_BLOCK_PTR->next_bb = EXIT_BLOCK_PTR;
+ EXIT_BLOCK_PTR->prev_bb = ENTRY_BLOCK_PTR;
+
+
+ /* Size the basic block table. The actual structures will be allocated
+ by find_basic_blocks_1, since we want to keep the structure pointers
+ stable across calls to find_basic_blocks. */
+ /* ??? This whole issue would be much simpler if we called find_basic_blocks
+ exactly once, and thereafter we don't have a single long chain of
+ instructions at all until close to the end of compilation when we
+ actually lay them out. */
+
+ basic_block_info = VEC_alloc (basic_block, gc, n_basic_blocks);
+ VEC_safe_grow (basic_block, gc, basic_block_info, n_basic_blocks);
+ memset (VEC_address (basic_block, basic_block_info), 0,
+ sizeof (basic_block) * n_basic_blocks);
+ SET_BASIC_BLOCK (ENTRY_BLOCK, ENTRY_BLOCK_PTR);
+ SET_BASIC_BLOCK (EXIT_BLOCK, EXIT_BLOCK_PTR);
+
+ find_basic_blocks_1 (f);
+
+ profile_status = PROFILE_ABSENT;
+
+ /* Tell make_edges to examine every block for out-going edges. */
+ FOR_EACH_BB (bb)
+ SET_STATE (bb, BLOCK_NEW);
+
+ /* Discover the edges of our cfg. */
+ make_edges (ENTRY_BLOCK_PTR->next_bb, EXIT_BLOCK_PTR->prev_bb, 0);
+
+ /* Do very simple cleanup now, for the benefit of code that runs between
+ here and cleanup_cfg, e.g. thread_prologue_and_epilogue_insns. */
+ tidy_fallthru_edges ();
+
+#ifdef ENABLE_CHECKING
+ verify_flow_info ();
+#endif
+ timevar_pop (TV_CFG);
+}
+
+static void
+mark_tablejump_edge (rtx label)
+{
+ basic_block bb;
+
+ gcc_assert (LABEL_P (label));
+ /* See comment in make_label_edge. */
+ if (INSN_UID (label) == 0)
+ return;
+ bb = BLOCK_FOR_INSN (label);
+ SET_STATE (bb, FULL_STATE (bb) | BLOCK_USED_BY_TABLEJUMP);
+}
+
+static void
+purge_dead_tablejump_edges (basic_block bb, rtx table)
+{
+ rtx insn = BB_END (bb), tmp;
+ rtvec vec;
+ int j;
+ edge_iterator ei;
+ edge e;
+
+ if (GET_CODE (PATTERN (table)) == ADDR_VEC)
+ vec = XVEC (PATTERN (table), 0);
+ else
+ vec = XVEC (PATTERN (table), 1);
+
+ for (j = GET_NUM_ELEM (vec) - 1; j >= 0; --j)
+ mark_tablejump_edge (XEXP (RTVEC_ELT (vec, j), 0));
+
+ /* Some targets (eg, ARM) emit a conditional jump that also
+ contains the out-of-range target. Scan for these and
+ add an edge if necessary. */
+ if ((tmp = single_set (insn)) != NULL
+ && SET_DEST (tmp) == pc_rtx
+ && GET_CODE (SET_SRC (tmp)) == IF_THEN_ELSE
+ && GET_CODE (XEXP (SET_SRC (tmp), 2)) == LABEL_REF)
+ mark_tablejump_edge (XEXP (XEXP (SET_SRC (tmp), 2), 0));
+
+ for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
+ {
+ if (FULL_STATE (e->dest) & BLOCK_USED_BY_TABLEJUMP)
+ SET_STATE (e->dest, FULL_STATE (e->dest)
+ & ~(size_t) BLOCK_USED_BY_TABLEJUMP);
+ else if (!(e->flags & (EDGE_ABNORMAL | EDGE_EH)))
+ {
+ remove_edge (e);
+ continue;
+ }
+ ei_next (&ei);
+ }
+}
+
+/* Scan basic block BB for possible BB boundaries inside the block
+ and create new basic blocks in the progress. */
+
+static void
+find_bb_boundaries (basic_block bb)
+{
+ basic_block orig_bb = bb;
+ rtx insn = BB_HEAD (bb);
+ rtx end = BB_END (bb);
+ rtx table;
+ rtx flow_transfer_insn = NULL_RTX;
+ edge fallthru = NULL;
+
+ if (insn == BB_END (bb))
+ return;
+
+ if (LABEL_P (insn))
+ insn = NEXT_INSN (insn);
+
+ /* Scan insn chain and try to find new basic block boundaries. */
+ while (1)
+ {
+ enum rtx_code code = GET_CODE (insn);
+
+ /* On code label, split current basic block. */
+ if (code == CODE_LABEL)
+ {
+ fallthru = split_block (bb, PREV_INSN (insn));
+ if (flow_transfer_insn)
+ BB_END (bb) = flow_transfer_insn;
+
+ bb = fallthru->dest;
+ remove_edge (fallthru);
+ flow_transfer_insn = NULL_RTX;
+ if (LABEL_ALT_ENTRY_P (insn))
+ make_edge (ENTRY_BLOCK_PTR, bb, 0);
+ }
+
+ /* In case we've previously seen an insn that effects a control
+ flow transfer, split the block. */
+ if (flow_transfer_insn && inside_basic_block_p (insn))
+ {
+ fallthru = split_block (bb, PREV_INSN (insn));
+ BB_END (bb) = flow_transfer_insn;
+ bb = fallthru->dest;
+ remove_edge (fallthru);
+ flow_transfer_insn = NULL_RTX;
+ }
+
+ if (control_flow_insn_p (insn))
+ flow_transfer_insn = insn;
+ if (insn == end)
+ break;
+ insn = NEXT_INSN (insn);
+ }
+
+ /* In case expander replaced normal insn by sequence terminating by
+ return and barrier, or possibly other sequence not behaving like
+ ordinary jump, we need to take care and move basic block boundary. */
+ if (flow_transfer_insn)
+ BB_END (bb) = flow_transfer_insn;
+
+ /* We've possibly replaced the conditional jump by conditional jump
+ followed by cleanup at fallthru edge, so the outgoing edges may
+ be dead. */
+ purge_dead_edges (bb);
+
+ /* purge_dead_edges doesn't handle tablejump's, but if we have split the
+ basic block, we might need to kill some edges. */
+ if (bb != orig_bb && tablejump_p (BB_END (bb), NULL, &table))
+ purge_dead_tablejump_edges (bb, table);
+}
+
+/* Assume that frequency of basic block B is known. Compute frequencies
+ and probabilities of outgoing edges. */
+
+static void
+compute_outgoing_frequencies (basic_block b)
+{
+ edge e, f;
+ edge_iterator ei;
+
+ if (EDGE_COUNT (b->succs) == 2)
+ {
+ rtx note = find_reg_note (BB_END (b), REG_BR_PROB, NULL);
+ int probability;
+
+ if (note)
+ {
+ probability = INTVAL (XEXP (note, 0));
+ e = BRANCH_EDGE (b);
+ e->probability = probability;
+ e->count = ((b->count * probability + REG_BR_PROB_BASE / 2)
+ / REG_BR_PROB_BASE);
+ f = FALLTHRU_EDGE (b);
+ f->probability = REG_BR_PROB_BASE - probability;
+ f->count = b->count - e->count;
+ return;
+ }
+ }
+
+ if (single_succ_p (b))
+ {
+ e = single_succ_edge (b);
+ e->probability = REG_BR_PROB_BASE;
+ e->count = b->count;
+ return;
+ }
+ guess_outgoing_edge_probabilities (b);
+ if (b->count)
+ FOR_EACH_EDGE (e, ei, b->succs)
+ e->count = ((b->count * e->probability + REG_BR_PROB_BASE / 2)
+ / REG_BR_PROB_BASE);
+}
+
+/* Assume that some pass has inserted labels or control flow
+ instructions within a basic block. Split basic blocks as needed
+ and create edges. */
+
+void
+find_many_sub_basic_blocks (sbitmap blocks)
+{
+ basic_block bb, min, max;
+
+ FOR_EACH_BB (bb)
+ SET_STATE (bb,
+ TEST_BIT (blocks, bb->index) ? BLOCK_TO_SPLIT : BLOCK_ORIGINAL);
+
+ FOR_EACH_BB (bb)
+ if (STATE (bb) == BLOCK_TO_SPLIT)
+ find_bb_boundaries (bb);
+
+ FOR_EACH_BB (bb)
+ if (STATE (bb) != BLOCK_ORIGINAL)
+ break;
+
+ min = max = bb;
+ for (; bb != EXIT_BLOCK_PTR; bb = bb->next_bb)
+ if (STATE (bb) != BLOCK_ORIGINAL)
+ max = bb;
+
+ /* Now re-scan and wire in all edges. This expect simple (conditional)
+ jumps at the end of each new basic blocks. */
+ make_edges (min, max, 1);
+
+ /* Update branch probabilities. Expect only (un)conditional jumps
+ to be created with only the forward edges. */
+ if (profile_status != PROFILE_ABSENT)
+ FOR_BB_BETWEEN (bb, min, max->next_bb, next_bb)
+ {
+ edge e;
+ edge_iterator ei;
+
+ if (STATE (bb) == BLOCK_ORIGINAL)
+ continue;
+ if (STATE (bb) == BLOCK_NEW)
+ {
+ bb->count = 0;
+ bb->frequency = 0;
+ FOR_EACH_EDGE (e, ei, bb->preds)
+ {
+ bb->count += e->count;
+ bb->frequency += EDGE_FREQUENCY (e);
+ }
+ }
+
+ compute_outgoing_frequencies (bb);
+ }
+
+ FOR_EACH_BB (bb)
+ SET_STATE (bb, 0);
+}