CbC/CbC_gcc: gcc/reorg.c comparison

comparison gcc/reorg.c @ 111:04ced10e8804

gcc 7

author	kono
date	Fri, 27 Oct 2017 22:46:09 +0900
parents	f6334be47118
children	84e7813d76e9

comparison

equal deleted inserted replaced

-:561a7518be6b
+:04ced10e8804
 /* Perform instruction reorganizations for delay slot filling.
-Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
+Copyright (C) 1992-2017 Free Software Foundation, Inc.
-2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
-Free Software Foundation, Inc.
 Contributed by Richard Kenner (kenner@vlsi1.ultra.nyu.edu).
 Hacked by Michael Tiemann (tiemann@cygnus.com).
 This file is part of GCC.
 allowed to be separated by placing an insn that sets CC0 (but not an insn
 that uses CC0; we could do this, but it doesn't seem worthwhile) in a
 delay slot.  In that case, we point each insn at the other with REG_CC_USER
 and REG_CC_SETTER notes.  Note that these restrictions affect very few
 machines because most RISC machines with delay slots will not use CC0
-(the RT is the only known exception at this point).
+(the RT is the only known exception at this point).  */
-Not yet implemented:
-The Acorn Risc Machine can conditionally execute most insns, so
-it is profitable to move single insns into a position to execute
-based on the condition code of the previous insn.
-The HP-PA can conditionally nullify insns, providing a similar
-effect to the ARM, differing mostly in which insn is "in charge".  */
 #include "config.h"
 #include "system.h"
 #include "coretypes.h"
-#include "tm.h"
+#include "backend.h"
-#include "diagnostic-core.h"
+#include "target.h"
 #include "rtl.h"
+#include "tree.h"
+#include "predict.h"
+#include "memmodel.h"
 #include "tm_p.h"
-#include "expr.h"
+#include "expmed.h"
-#include "function.h"
 #include "insn-config.h"
-#include "conditions.h"
+#include "emit-rtl.h"
-#include "hard-reg-set.h"
-#include "basic-block.h"
-#include "regs.h"
 #include "recog.h"
-#include "flags.h"
-#include "output.h"
-#include "obstack.h"
 #include "insn-attr.h"
 #include "resource.h"
-#include "except.h"
 #include "params.h"
-#include "timevar.h"
-#include "target.h"
 #include "tree-pass.h"
-#ifdef DELAY_SLOTS
+/* First, some functions that were used before GCC got a control flow graph.
-#ifndef ANNUL_IFTRUE_SLOTS
+These functions are now only used here in reorg.c, and have therefore
-#define eligible_for_annul_true(INSN, SLOTS, TRIAL, FLAGS) 0
+been moved here to avoid inadvertent misuse elsewhere in the compiler.  */
-#endif
-#ifndef ANNUL_IFFALSE_SLOTS
+/* Return the last label to mark the same position as LABEL.  Return LABEL
-#define eligible_for_annul_false(INSN, SLOTS, TRIAL, FLAGS) 0
+itself if it is null or any return rtx.  */
-#endif
+static rtx
+skip_consecutive_labels (rtx label_or_return)
+{
+rtx_insn *insn;
+if (label_or_return && ANY_RETURN_P (label_or_return))
+return label_or_return;
+rtx_insn *label = as_a <rtx_insn *> (label_or_return);
+for (insn = label; insn != 0 && !INSN_P (insn); insn = NEXT_INSN (insn))
+if (LABEL_P (insn))
+label = insn;
+return label;
+}
+/* INSN uses CC0 and is being moved into a delay slot.  Set up REG_CC_SETTER
+and REG_CC_USER notes so we can find it.  */
+static void
+link_cc0_insns (rtx_insn *insn)
+{
+rtx user = next_nonnote_insn (insn);
+if (NONJUMP_INSN_P (user) && GET_CODE (PATTERN (user)) == SEQUENCE)
+user = XVECEXP (PATTERN (user), 0, 0);
+add_reg_note (user, REG_CC_SETTER, insn);
+add_reg_note (insn, REG_CC_USER, user);
+}
 /* Insns which have delay slots that have not yet been filled.  */
 static struct obstack unfilled_slots_obstack;
 static rtx *unfilled_firstobj;
 /* Define macros to refer to the first and last slot containing unfilled
 insns.  These are used because the list may move and its address
 should be recomputed at each use.  */
 #define unfilled_slots_base	\
-((rtx *) obstack_base (&unfilled_slots_obstack))
+((rtx_insn **) obstack_base (&unfilled_slots_obstack))
 #define unfilled_slots_next	\
-((rtx *) obstack_next_free (&unfilled_slots_obstack))
+((rtx_insn **) obstack_next_free (&unfilled_slots_obstack))
-/* Points to the label before the end of the function.  */
+/* Points to the label before the end of the function, or before a
-static rtx end_of_function_label;
+return insn.  */
+static rtx_code_label *function_return_label;
+/* Likewise for a simple_return.  */
+static rtx_code_label *function_simple_return_label;
 /* Mapping between INSN_UID's and position in the code since INSN_UID's do
 not always monotonically increase.  */
 static int *uid_to_ruid;
 /* Highest valid index in `uid_to_ruid'.  */
 static int max_uid;
-static int stop_search_p (rtx, int);
+static int stop_search_p (rtx_insn *, int);
 static int resource_conflicts_p (struct resources *, struct resources *);
 static int insn_references_resource_p (rtx, struct resources *, bool);
 static int insn_sets_resource_p (rtx, struct resources *, bool);
-static rtx find_end_label (void);
+static rtx_code_label *find_end_label (rtx);
-static rtx emit_delay_sequence (rtx, rtx, int);
+static rtx_insn *emit_delay_sequence (rtx_insn *, const vec<rtx_insn *> &,
-static rtx add_to_delay_list (rtx, rtx);
+				      int);
-static rtx delete_from_delay_slot (rtx);
+static void add_to_delay_list (rtx_insn *, vec<rtx_insn *> *);
-static void delete_scheduled_jump (rtx);
+static rtx_insn *delete_from_delay_slot (rtx_insn *);
+static void delete_scheduled_jump (rtx_insn *);
 static void note_delay_statistics (int, int);
-#if defined(ANNUL_IFFALSE_SLOTS) || defined(ANNUL_IFTRUE_SLOTS)
+static int get_jump_flags (const rtx_insn *, rtx);
-static rtx optimize_skip (rtx);
+static int mostly_true_jump (rtx);
-#endif
+static rtx get_branch_condition (const rtx_insn *, rtx);
-static int get_jump_flags (rtx, rtx);
+static int condition_dominates_p (rtx, const rtx_insn *);
-static int rare_destination (rtx);
+static int redirect_with_delay_slots_safe_p (rtx_insn *, rtx, rtx);
-static int mostly_true_jump (rtx, rtx);
+static int redirect_with_delay_list_safe_p (rtx_insn *, rtx,
-static rtx get_branch_condition (rtx, rtx);
+					    const vec<rtx_insn *> &);
-static int condition_dominates_p (rtx, rtx);
+static int check_annul_list_true_false (int, const vec<rtx_insn *> &);
-static int redirect_with_delay_slots_safe_p (rtx, rtx, rtx);
+static void steal_delay_list_from_target (rtx_insn *, rtx, rtx_sequence *,
-static int redirect_with_delay_list_safe_p (rtx, rtx, rtx);
+					  vec<rtx_insn *> *,
-static int check_annul_list_true_false (int, rtx);
+					  struct resources *,
-static rtx steal_delay_list_from_target (rtx, rtx, rtx, rtx,
+					  struct resources *,
-					 struct resources *,
+					  struct resources *,
-					 struct resources *,
+					  int, int *, int *,
-					 struct resources *,
+					  rtx *);
-					 int, int *, int *, rtx *);
+static void steal_delay_list_from_fallthrough (rtx_insn *, rtx, rtx_sequence *,
-static rtx steal_delay_list_from_fallthrough (rtx, rtx, rtx, rtx,
+					       vec<rtx_insn *> *,
-					      struct resources *,
+					       struct resources *,
-					      struct resources *,
+					       struct resources *,
-					      struct resources *,
+					       struct resources *,
-					      int, int *, int *);
+					       int, int *, int *);
-static void try_merge_delay_insns (rtx, rtx);
+static void try_merge_delay_insns (rtx_insn *, rtx_insn *);
-static rtx redundant_insn (rtx, rtx, rtx);
+static rtx_insn *redundant_insn (rtx, rtx_insn *, const vec<rtx_insn *> &);
 static int own_thread_p (rtx, rtx, int);
-static void update_block (rtx, rtx);
+static void update_block (rtx_insn *, rtx_insn *);
-static int reorg_redirect_jump (rtx, rtx);
+static int reorg_redirect_jump (rtx_jump_insn *, rtx);
-static void update_reg_dead_notes (rtx, rtx);
+static void update_reg_dead_notes (rtx_insn *, rtx_insn *);
-static void fix_reg_dead_note (rtx, rtx);
+static void fix_reg_dead_note (rtx_insn *, rtx);
-static void update_reg_unused_notes (rtx, rtx);
+static void update_reg_unused_notes (rtx_insn *, rtx);
 static void fill_simple_delay_slots (int);
-static rtx fill_slots_from_thread (rtx, rtx, rtx, rtx,
+static void fill_slots_from_thread (rtx_jump_insn *, rtx, rtx, rtx,
-				   int, int, int, int,
+				    int, int, int, int,
-				   int *, rtx);
+				    int *, vec<rtx_insn *> *);
 static void fill_eager_delay_slots (void);
-static void relax_delay_slots (rtx);
+static void relax_delay_slots (rtx_insn *);
-#ifdef HAVE_return
+static void make_return_insns (rtx_insn *);
-static void make_return_insns (rtx);
-#endif
+/* A wrapper around next_active_insn which takes care to return ret_rtx
+unchanged.  */
+static rtx
+first_active_target_insn (rtx insn)
+{
+if (ANY_RETURN_P (insn))
+return insn;
+return next_active_insn (as_a <rtx_insn *> (insn));
+}
+/* Return true iff INSN is a simplejump, or any kind of return insn.  */
+static bool
+simplejump_or_return_p (rtx insn)
+{
+return (JUMP_P (insn)
+	  && (simplejump_p (as_a <rtx_insn *> (insn))
+	      || ANY_RETURN_P (PATTERN (insn))));
+}
 /* Return TRUE if this insn should stop the search for insn to fill delay
 slots.  LABELS_P indicates that labels should terminate the search.
 In all cases, jumps terminate the search.  */
 static int
-stop_search_p (rtx insn, int labels_p)
+stop_search_p (rtx_insn *insn, int labels_p)
 {
 if (insn == 0)
 return 1;
 /* If the insn can throw an exception that is caught within the function,
 static int
 resource_conflicts_p (struct resources *res1, struct resources *res2)
 {
 if ((res1->cc && res2->cc) || (res1->memory && res2->memory)
-|| (res1->unch_memory && res2->unch_memory)
 || res1->volatil || res2->volatil)
 return 1;
-#ifdef HARD_REG_SET
+return hard_reg_set_intersect_p (res1->regs, res2->regs);
-return (res1->regs & res2->regs) != HARD_CONST (0);
-#else
-{
-int i;
-for (i = 0; i < HARD_REG_SET_LONGS; i++)
-if ((res1->regs[i] & res2->regs[i]) != 0)
-	return 1;
-return 0;
-}
-#endif
 }
 /* Return TRUE if any resource marked in RES, a `struct resources', is
 referenced by INSN.  If INCLUDE_DELAYED_EFFECTS is set, return if the called
 routine is using those resources.
 turned into a jump to the label unconditionally.  In particular, the
 label cannot be placed before a RETURN insn with a filled delay slot.
 ??? There may be a problem with the current implementation.  Suppose
 we start with a bare RETURN insn and call find_end_label.  It may set
-end_of_function_label just before the RETURN.  Suppose the machinery
+function_return_label just before the RETURN.  Suppose the machinery
 is able to fill the delay slot of the RETURN insn afterwards.  Then
-end_of_function_label is no longer valid according to the property
+function_return_label is no longer valid according to the property
 described above and find_end_label will still return it unmodified.
 Note that this is probably mitigated by the following observation:
-once end_of_function_label is made, it is very likely the target of
+once function_return_label is made, it is very likely the target of
 a jump, so filling the delay slot of the RETURN will be much more
-difficult.  */
+difficult.
+KIND is either simple_return_rtx or ret_rtx, indicating which type of
-static rtx
+return we're looking for.  */
-find_end_label (void)
-{
+static rtx_code_label *
-rtx insn;
+find_end_label (rtx kind)
+{
+rtx_insn *insn;
+rtx_code_label **plabel;
+if (kind == ret_rtx)
+plabel = &function_return_label;
+else
+{
+gcc_assert (kind == simple_return_rtx);
+plabel = &function_simple_return_label;
+}
 /* If we found one previously, return it.  */
-if (end_of_function_label)
+if (*plabel)
-return end_of_function_label;
+return *plabel;
 /* Otherwise, see if there is a label at the end of the function.  If there
 is, it must be that RETURN insns aren't needed, so that is our return
 label and we don't have to do anything else.  */
 		 || GET_CODE (PATTERN (insn)) == CLOBBER)))
 insn = PREV_INSN (insn);
 /* When a target threads its epilogue we might already have a
 suitable return insn.  If so put a label before it for the
-end_of_function_label.  */
+function_return_label.  */
 if (BARRIER_P (insn)
 && JUMP_P (PREV_INSN (insn))
-&& GET_CODE (PATTERN (PREV_INSN (insn))) == RETURN)
+&& PATTERN (PREV_INSN (insn)) == kind)
 {
-rtx temp = PREV_INSN (PREV_INSN (insn));
+rtx_insn *temp = PREV_INSN (PREV_INSN (insn));
-end_of_function_label = gen_label_rtx ();
+rtx_code_label *label = gen_label_rtx ();
-LABEL_NUSES (end_of_function_label) = 0;
+LABEL_NUSES (label) = 0;
-/* Put the label before an USE insns that may precede the RETURN insn.  */
+/* Put the label before any USE insns that may precede the RETURN
+	 insn.  */
 while (GET_CODE (temp) == USE)
 	temp = PREV_INSN (temp);
-emit_label_after (end_of_function_label, temp);
+emit_label_after (label, temp);
+*plabel = label;
 }
 else if (LABEL_P (insn))
-end_of_function_label = insn;
+*plabel = as_a <rtx_code_label *> (insn);
 else
 {
-end_of_function_label = gen_label_rtx ();
+rtx_code_label *label = gen_label_rtx ();
-LABEL_NUSES (end_of_function_label) = 0;
+LABEL_NUSES (label) = 0;
 /* If the basic block reorder pass moves the return insn to
 	 some other place try to locate it again and put our
-	 end_of_function_label there.  */
+	 function_return_label there.  */
-while (insn && ! (JUMP_P (insn)
+while (insn && ! (JUMP_P (insn) && (PATTERN (insn) == kind)))
-		        && (GET_CODE (PATTERN (insn)) == RETURN)))
 	insn = PREV_INSN (insn);
 if (insn)
 	{
 	  insn = PREV_INSN (insn);
-	  /* Put the label before an USE insns that may proceed the
+	  /* Put the label before any USE insns that may precede the
 	     RETURN insn.  */
 	  while (GET_CODE (insn) == USE)
 	    insn = PREV_INSN (insn);
-	  emit_label_after (end_of_function_label, insn);
+	  emit_label_after (label, insn);
 	}
 else
 	{
-#ifdef HAVE_epilogue
+	  if (targetm.have_epilogue () && ! targetm.have_return ())
-	  if (HAVE_epilogue
+	    /* The RETURN insn has its delay slot filled so we cannot
-#ifdef HAVE_return
+	       emit the label just before it.  Since we already have
-	      && ! HAVE_return
+	       an epilogue and cannot emit a new RETURN, we cannot
-#endif
+	       emit the label at all.  */
-	      )
+	    return NULL;
-	    {
-	      /* The RETURN insn has its delay slot filled so we cannot
-		 emit the label just before it.  Since we already have
-		 an epilogue and cannot emit a new RETURN, we cannot
-		 emit the label at all.  */
-	      end_of_function_label = NULL_RTX;
-	      return end_of_function_label;
-	    }
-#endif /* HAVE_epilogue */
 	  /* Otherwise, make a new label and emit a RETURN and BARRIER,
 	     if needed.  */
-	  emit_label (end_of_function_label);
+	  emit_label (label);
-#ifdef HAVE_return
+	  if (targetm.have_return ())
-	  /* We don't bother trying to create a return insn if the
-	     epilogue has filled delay-slots; we would have to try and
-	     move the delay-slot fillers to the delay-slots for the new
-	     return insn or in front of the new return insn.  */
-	  if (crtl->epilogue_delay_list == NULL
-	      && HAVE_return)
 	    {
 	      /* The return we make may have delay slots too.  */
-	      rtx insn = gen_return ();
+	      rtx_insn *pat = targetm.gen_return ();
-	      insn = emit_jump_insn (insn);
+	      rtx_insn *insn = emit_jump_insn (pat);
+	      set_return_jump_label (insn);
 	      emit_barrier ();
 	      if (num_delay_slots (insn) > 0)
 		obstack_ptr_grow (&unfilled_slots_obstack, insn);
 	    }
-#endif
+	}
-	}
+*plabel = label;
 }
 /* Show one additional use for this label so it won't go away until
 we are done.  */
-++LABEL_NUSES (end_of_function_label);
+++LABEL_NUSES (*plabel);
-return end_of_function_label;
+return *plabel;
 }
 /* Put INSN and LIST together in a SEQUENCE rtx of LENGTH, and replace
 the pattern of INSN with the SEQUENCE.
-Chain the insns so that NEXT_INSN of each insn in the sequence points to
+Returns the insn containing the SEQUENCE that replaces INSN.  */
-the next and NEXT_INSN of the last insn in the sequence points to
-the first insn after the sequence.  Similarly for PREV_INSN.  This makes
+static rtx_insn *
-it easier to scan all insns.
+emit_delay_sequence (rtx_insn *insn, const vec<rtx_insn *> &list, int length)
+{
-Returns the SEQUENCE that replaces INSN.  */
-static rtx
-emit_delay_sequence (rtx insn, rtx list, int length)
-{
-int i = 1;
-rtx li;
-int had_barrier = 0;
 /* Allocate the rtvec to hold the insns and the SEQUENCE.  */
 rtvec seqv = rtvec_alloc (length + 1);
 rtx seq = gen_rtx_SEQUENCE (VOIDmode, seqv);
-rtx seq_insn = make_insn_raw (seq);
+rtx_insn *seq_insn = make_insn_raw (seq);
-rtx first = get_insns ();
-rtx last = get_last_insn ();
+/* If DELAY_INSN has a location, use it for SEQ_INSN.  If DELAY_INSN does
+not have a location, but one of the delayed insns does, we pick up a
-/* Make a copy of the insn having delay slots.  */
+location from there later.  */
-rtx delay_insn = copy_rtx (insn);
+INSN_LOCATION (seq_insn) = INSN_LOCATION (insn);
-/* If INSN is followed by a BARRIER, delete the BARRIER since it will only
+/* Unlink INSN from the insn chain, so that we can put it into
-confuse further processing.  Update LAST in case it was the last insn.
+the SEQUENCE.   Remember where we want to emit SEQUENCE in AFTER.  */
-We will put the BARRIER back in later.  */
+rtx_insn *after = PREV_INSN (insn);
-if (NEXT_INSN (insn) && BARRIER_P (NEXT_INSN (insn)))
+remove_insn (insn);
-{
+SET_NEXT_INSN (insn) = SET_PREV_INSN (insn) = NULL;
-delete_related_insns (NEXT_INSN (insn));
-last = get_last_insn ();
-had_barrier = 1;
-}
-/* Splice our SEQUENCE into the insn stream where INSN used to be.  */
-NEXT_INSN (seq_insn) = NEXT_INSN (insn);
-PREV_INSN (seq_insn) = PREV_INSN (insn);
-if (insn != last)
-PREV_INSN (NEXT_INSN (seq_insn)) = seq_insn;
-if (insn != first)
-NEXT_INSN (PREV_INSN (seq_insn)) = seq_insn;
-/* Note the calls to set_new_first_and_last_insn must occur after
-SEQ_INSN has been completely spliced into the insn stream.
-Otherwise CUR_INSN_UID will get set to an incorrect value because
-set_new_first_and_last_insn will not find SEQ_INSN in the chain.  */
-if (insn == last)
-set_new_first_and_last_insn (first, seq_insn);
-if (insn == first)
-set_new_first_and_last_insn (seq_insn, last);
 /* Build our SEQUENCE and rebuild the insn chain.  */
-XVECEXP (seq, 0, 0) = delay_insn;
+start_sequence ();
-INSN_DELETED_P (delay_insn) = 0;
+XVECEXP (seq, 0, 0) = emit_insn (insn);
-PREV_INSN (delay_insn) = PREV_INSN (seq_insn);
+unsigned int delay_insns = list.length ();
-INSN_LOCATOR (seq_insn) = INSN_LOCATOR (delay_insn);
+gcc_assert (delay_insns == (unsigned int) length);
+for (unsigned int i = 0; i < delay_insns; i++)
-for (li = list; li; li = XEXP (li, 1), i++)
+{
-{
+rtx_insn *tem = list[i];
-rtx tem = XEXP (li, 0);
 rtx note, next;
 /* Show that this copy of the insn isn't deleted.  */
-INSN_DELETED_P (tem) = 0;
+tem->set_undeleted ();
-XVECEXP (seq, 0, i) = tem;
+/* Unlink insn from its original place, and re-emit it into
-PREV_INSN (tem) = XVECEXP (seq, 0, i - 1);
+	 the sequence.  */
-NEXT_INSN (XVECEXP (seq, 0, i - 1)) = tem;
+SET_NEXT_INSN (tem) = SET_PREV_INSN (tem) = NULL;
+XVECEXP (seq, 0, i + 1) = emit_insn (tem);
 /* SPARC assembler, for instance, emit warning when debug info is output
 into the delay slot.  */
-if (INSN_LOCATOR (tem) && !INSN_LOCATOR (seq_insn))
+if (INSN_LOCATION (tem) && !INSN_LOCATION (seq_insn))
-	INSN_LOCATOR (seq_insn) = INSN_LOCATOR (tem);
+	INSN_LOCATION (seq_insn) = INSN_LOCATION (tem);
-INSN_LOCATOR (tem) = 0;
+INSN_LOCATION (tem) = 0;
 for (note = REG_NOTES (tem); note; note = next)
 	{
 	  next = XEXP (note, 1);
 	  switch (REG_NOTE_KIND (note))
 	    default:
 	      break;
 	    }
 	}
 }
+end_sequence ();
-NEXT_INSN (XVECEXP (seq, 0, length)) = NEXT_INSN (seq_insn);
+/* Splice our SEQUENCE into the insn stream where INSN used to be.  */
-/* If the previous insn is a SEQUENCE, update the NEXT_INSN pointer on the
+add_insn_after (seq_insn, after, NULL);
-last insn in that SEQUENCE to point to us.  Similarly for the first
-insn in the following insn if it is a SEQUENCE.  */
-if (PREV_INSN (seq_insn) && NONJUMP_INSN_P (PREV_INSN (seq_insn))
-&& GET_CODE (PATTERN (PREV_INSN (seq_insn))) == SEQUENCE)
-NEXT_INSN (XVECEXP (PATTERN (PREV_INSN (seq_insn)), 0,
-			XVECLEN (PATTERN (PREV_INSN (seq_insn)), 0) - 1))
-= seq_insn;
-if (NEXT_INSN (seq_insn) && NONJUMP_INSN_P (NEXT_INSN (seq_insn))
-&& GET_CODE (PATTERN (NEXT_INSN (seq_insn))) == SEQUENCE)
-PREV_INSN (XVECEXP (PATTERN (NEXT_INSN (seq_insn)), 0, 0)) = seq_insn;
-/* If there used to be a BARRIER, put it back.  */
-if (had_barrier)
-emit_barrier_after (seq_insn);
-gcc_assert (i == length + 1);
 return seq_insn;
 }
 /* Add INSN to DELAY_LIST and return the head of the new list.  The list must
 be in the order in which the insns are to be executed.  */
-static rtx
+static void
-add_to_delay_list (rtx insn, rtx delay_list)
+add_to_delay_list (rtx_insn *insn, vec<rtx_insn *> *delay_list)
 {
-/* If we have an empty list, just make a new list element.  If
+/* If INSN has its block number recorded, clear it since we may
-INSN has its block number recorded, clear it since we may
 be moving the insn to a new block.  */
-if (delay_list == 0)
-{
 clear_hashed_info_for_insn (insn);
-return gen_rtx_INSN_LIST (VOIDmode, insn, NULL_RTX);
+delay_list->safe_push (insn);
-}
-/* Otherwise this must be an INSN_LIST.  Add INSN to the end of the
-list.  */
-XEXP (delay_list, 1) = add_to_delay_list (insn, XEXP (delay_list, 1));
-return delay_list;
 }
 /* Delete INSN from the delay slot of the insn that it is in, which may
 produce an insn with no delay slots.  Return the new insn.  */
-static rtx
+static rtx_insn *
-delete_from_delay_slot (rtx insn)
+delete_from_delay_slot (rtx_insn *insn)
 {
-rtx trial, seq_insn, seq, prev;
+rtx_insn *trial, *seq_insn, *prev;
-rtx delay_list = 0;
+rtx_sequence *seq;
 int i;
 int had_barrier = 0;
 /* We first must find the insn containing the SEQUENCE with INSN in its
 delay slot.  Do this by finding an insn, TRIAL, where
 PREV_INSN (NEXT_INSN (trial)) == trial;
 trial = NEXT_INSN (trial))
 ;
 seq_insn = PREV_INSN (NEXT_INSN (trial));
-seq = PATTERN (seq_insn);
+seq = as_a <rtx_sequence *> (PATTERN (seq_insn));
 if (NEXT_INSN (seq_insn) && BARRIER_P (NEXT_INSN (seq_insn)))
 had_barrier = 1;
 /* Create a delay list consisting of all the insns other than the one
 we are deleting (unless we were the only one).  */
-if (XVECLEN (seq, 0) > 2)
+auto_vec<rtx_insn *, 5> delay_list;
-for (i = 1; i < XVECLEN (seq, 0); i++)
+if (seq->len () > 2)
-if (XVECEXP (seq, 0, i) != insn)
+for (i = 1; i < seq->len (); i++)
-	delay_list = add_to_delay_list (XVECEXP (seq, 0, i), delay_list);
+if (seq->insn (i) != insn)
+	add_to_delay_list (seq->insn (i), &delay_list);
 /* Delete the old SEQUENCE, re-emit the insn that used to have the delay
 list, and rebuild the delay list if non-empty.  */
 prev = PREV_INSN (seq_insn);
-trial = XVECEXP (seq, 0, 0);
+trial = seq->insn (0);
 delete_related_insns (seq_insn);
 add_insn_after (trial, prev, NULL);
 /* If there was a barrier after the old SEQUENCE, remit it.  */
 if (had_barrier)
 emit_barrier_after (trial);
 /* If there are any delay insns, remit them.  Otherwise clear the
 annul flag.  */
-if (delay_list)
+if (!delay_list.is_empty ())
 trial = emit_delay_sequence (trial, delay_list, XVECLEN (seq, 0) - 2);
-else if (INSN_P (trial))
+else if (JUMP_P (trial))
 INSN_ANNULLED_BRANCH_P (trial) = 0;
 INSN_FROM_TARGET_P (insn) = 0;
 /* Show we need to fill this insn again.  */
 /* Delete INSN, a JUMP_INSN.  If it is a conditional jump, we must track down
 the insn that sets CC0 for it and delete it too.  */
 static void
-delete_scheduled_jump (rtx insn)
+delete_scheduled_jump (rtx_insn *insn)
 {
 /* Delete the insn that sets cc0 for us.  On machines without cc0, we could
 delete the insn that sets the condition code, but it is hard to find it.
 Since this case is rare anyway, don't bother trying; there would likely
 be other insns that became dead anyway, which we wouldn't know to
 delete.  */
-#ifdef HAVE_cc0
+if (HAVE_cc0 && reg_mentioned_p (cc0_rtx, insn))
-if (reg_mentioned_p (cc0_rtx, insn))
 {
 rtx note = find_reg_note (insn, REG_CC_SETTER, NULL_RTX);
 /* If a reg-note was found, it points to an insn to set CC0.  This
 	 insn is in the delay list of some other insn.  So delete it from
 	 the delay list it was in.  */
 if (note)
 	{
 	  if (! FIND_REG_INC_NOTE (XEXP (note, 0), NULL_RTX)
 	      && sets_cc0_p (PATTERN (XEXP (note, 0))) == 1)
-	    delete_from_delay_slot (XEXP (note, 0));
+	    delete_from_delay_slot (as_a <rtx_insn *> (XEXP (note, 0)));
 	}
 else
 	{
 	  /* The insn setting CC0 is our previous insn, but it may be in
 	     a delay slot.  It will be the last insn in the delay slot, if
 	     it is.  */
-	  rtx trial = previous_insn (insn);
+	  rtx_insn *trial = previous_insn (insn);
 	  if (NOTE_P (trial))
 	    trial = prev_nonnote_insn (trial);
 	  if (sets_cc0_p (PATTERN (trial)) != 1
 	      || FIND_REG_INC_NOTE (trial, NULL_RTX))
 	    return;
 	    delete_related_insns (trial);
 	  else
 	    delete_from_delay_slot (trial);
 	}
 }
-#endif
 delete_related_insns (insn);
 }
 /* Counters for delay-slot filling.  */
 if (slots_filled > MAX_DELAY_HISTOGRAM)
 slots_filled = MAX_DELAY_HISTOGRAM;
 num_filled_delays[index][slots_filled][reorg_pass_number]++;
 }
-#if defined(ANNUL_IFFALSE_SLOTS) || defined(ANNUL_IFTRUE_SLOTS)
 /* Optimize the following cases:
 1.  When a conditional branch skips over only one instruction,
 use an annulling branch and put that insn in the delay slot.
 Use either a branch that annuls when the condition if true or
 INSN is a JUMP_INSN.
 This should be expanded to skip over N insns, where N is the number
 of delay slots required.  */
-static rtx
+static void
-optimize_skip (rtx insn)
+optimize_skip (rtx_jump_insn *insn, vec<rtx_insn *> *delay_list)
 {
-rtx trial = next_nonnote_insn (insn);
+rtx_insn *trial = next_nonnote_insn (insn);
-rtx next_trial = next_active_insn (trial);
+rtx_insn *next_trial = next_active_insn (trial);
-rtx delay_list = 0;
 int flags;
 flags = get_jump_flags (insn, JUMP_LABEL (insn));
 if (trial == 0
 || !NONJUMP_INSN_P (trial)
 || GET_CODE (PATTERN (trial)) == SEQUENCE
 || recog_memoized (trial) < 0
 || (! eligible_for_annul_false (insn, 0, trial, flags)
 	  && ! eligible_for_annul_true (insn, 0, trial, flags))
+|| RTX_FRAME_RELATED_P (trial)
 || can_throw_internal (trial))
-return 0;
+return;
 /* There are two cases where we are just executing one insn (we assume
 here that a branch requires only one insn; this should be generalized
 at some point):  Where the branch goes around a single insn or where
 we have one insn followed by a branch to the same label we branch to.
 In both of these cases, inverting the jump and annulling the delay
 slot give the same effect in fewer insns.  */
-if ((next_trial == next_active_insn (JUMP_LABEL (insn))
+if (next_trial == next_active_insn (JUMP_LABEL_AS_INSN (insn))
-&& ! (next_trial == 0 && crtl->epilogue_delay_list != 0))
 || (next_trial != 0
-	  && JUMP_P (next_trial)
+	  && simplejump_or_return_p (next_trial)
-	  && JUMP_LABEL (insn) == JUMP_LABEL (next_trial)
+	  && JUMP_LABEL (insn) == JUMP_LABEL (next_trial)))
-	  && (simplejump_p (next_trial)
-	      || GET_CODE (PATTERN (next_trial)) == RETURN)))
 {
 if (eligible_for_annul_false (insn, 0, trial, flags))
 	{
 	  if (invert_jump (insn, JUMP_LABEL (insn), 1))
 	    INSN_FROM_TARGET_P (trial) = 1;
 	  else if (! eligible_for_annul_true (insn, 0, trial, flags))
-	    return 0;
+	    return;
 	}
-delay_list = add_to_delay_list (trial, NULL_RTX);
+add_to_delay_list (trial, delay_list);
 next_trial = next_active_insn (trial);
 update_block (trial, trial);
 delete_related_insns (trial);
 /* Also, if we are targeting an unconditional
 	 branch, thread our jump to the target of that branch.  Don't
 	 change this into a RETURN here, because it may not accept what
 	 we have in the delay slot.  We'll fix this up later.  */
-if (next_trial && JUMP_P (next_trial)
+if (next_trial && simplejump_or_return_p (next_trial))
-	  && (simplejump_p (next_trial)
-	      || GET_CODE (PATTERN (next_trial)) == RETURN))
 	{
 	  rtx target_label = JUMP_LABEL (next_trial);
-	  if (target_label == 0)
+	  if (ANY_RETURN_P (target_label))
-	    target_label = find_end_label ();
+	    target_label = find_end_label (target_label);
 	  if (target_label)
 	    {
 	      /* Recompute the flags based on TARGET_LABEL since threading
 		 the jump to TARGET_LABEL may change the direction of the
 	    }
 	}
 INSN_ANNULLED_BRANCH_P (insn) = 1;
 }
+}
-return delay_list;
-}
-#endif
 /*  Encode and return branch direction and prediction information for
 INSN assuming it will jump to LABEL.
 Non conditional branches return no direction information and
 are predicted as very likely taken.  */
 static int
-get_jump_flags (rtx insn, rtx label)
+get_jump_flags (const rtx_insn *insn, rtx label)
 {
 int flags;
 /* get_jump_flags can be passed any insn with delay slots, these may
 be INSNs, CALL_INSNs, or JUMP_INSNs.  Only JUMP_INSNs have branch
 direction information, and only if they are conditional jumps.
-If LABEL is zero, then there is no way to determine the branch
+If LABEL is a return, then there is no way to determine the branch
 direction.  */
 if (JUMP_P (insn)
 && (condjump_p (insn) || condjump_in_parallel_p (insn))
+&& !ANY_RETURN_P (label)
 && INSN_UID (insn) <= max_uid
-&& label != 0
 && INSN_UID (label) <= max_uid)
 flags
 = (uid_to_ruid[INSN_UID (label)] > uid_to_ruid[INSN_UID (insn)])
 	 ? ATTR_FLAG_forward : ATTR_FLAG_backward;
 /* No valid direction information.  */
 else
 flags = 0;
-/* If insn is a conditional branch call mostly_true_jump to get
-determine the branch prediction.
-Non conditional branches are predicted as very likely taken.  */
-if (JUMP_P (insn)
-&& (condjump_p (insn) || condjump_in_parallel_p (insn)))
-{
-int prediction;
-prediction = mostly_true_jump (insn, get_branch_condition (insn, label));
-switch (prediction)
-	{
-	case 2:
-	  flags |= (ATTR_FLAG_very_likely | ATTR_FLAG_likely);
-	  break;
-	case 1:
-	  flags |= ATTR_FLAG_likely;
-	  break;
-	case 0:
-	  flags |= ATTR_FLAG_unlikely;
-	  break;
-	case -1:
-	  flags |= (ATTR_FLAG_very_unlikely | ATTR_FLAG_unlikely);
-	  break;
-	default:
-	  gcc_unreachable ();
-	}
-}
-else
-flags |= (ATTR_FLAG_very_likely | ATTR_FLAG_likely);
 return flags;
-}
-/* Return 1 if INSN is a destination that will be branched to rarely (the
-return point of a function); return 2 if DEST will be branched to very
-rarely (a call to a function that doesn't return).  Otherwise,
-return 0.  */
-static int
-rare_destination (rtx insn)
-{
-int jump_count = 0;
-rtx next;
-for (; insn; insn = next)
-{
-if (NONJUMP_INSN_P (insn) && GET_CODE (PATTERN (insn)) == SEQUENCE)
-	insn = XVECEXP (PATTERN (insn), 0, 0);
-next = NEXT_INSN (insn);
-switch (GET_CODE (insn))
-	{
-	case CODE_LABEL:
-	  return 0;
-	case BARRIER:
-	  /* A BARRIER can either be after a JUMP_INSN or a CALL_INSN.  We
-	     don't scan past JUMP_INSNs, so any barrier we find here must
-	     have been after a CALL_INSN and hence mean the call doesn't
-	     return.  */
-	  return 2;
-	case JUMP_INSN:
-	  if (GET_CODE (PATTERN (insn)) == RETURN)
-	    return 1;
-	  else if (simplejump_p (insn)
-		   && jump_count++ < 10)
-	    next = JUMP_LABEL (insn);
-	  else
-	    return 0;
-	default:
-	  break;
-	}
-}
-/* If we got here it means we hit the end of the function.  So this
-is an unlikely destination.  */
-return 1;
 }
 /* Return truth value of the statement that this branch
 is mostly taken.  If we think that the branch is extremely likely
 to be taken, we return 2.  If the branch is slightly more likely to be
 taken, return 1.  If the branch is slightly less likely to be taken,
-return 0 and if the branch is highly unlikely to be taken, return -1.
+return 0 and if the branch is highly unlikely to be taken, return -1.  */
-CONDITION, if nonzero, is the condition that JUMP_INSN is testing.  */
 static int
-mostly_true_jump (rtx jump_insn, rtx condition)
+mostly_true_jump (rtx jump_insn)
 {
-rtx target_label = JUMP_LABEL (jump_insn);
-rtx note;
-int rare_dest, rare_fallthrough;
 /* If branch probabilities are available, then use that number since it
 always gives a correct answer.  */
-note = find_reg_note (jump_insn, REG_BR_PROB, 0);
+rtx note = find_reg_note (jump_insn, REG_BR_PROB, 0);
 if (note)
 {
-int prob = INTVAL (XEXP (note, 0));
+int prob = profile_probability::from_reg_br_prob_note (XINT (note, 0))
+			.to_reg_br_prob_base ();
 if (prob >= REG_BR_PROB_BASE * 9 / 10)
 	return 2;
 else if (prob >= REG_BR_PROB_BASE / 2)
 	return 1;
 	return 0;
 else
 	return -1;
 }
-/* Look at the relative rarities of the fallthrough and destination.  If
+/* If there is no note, assume branches are not taken.
-they differ, we can predict the branch that way.  */
+This should be rare.  */
-rare_dest = rare_destination (target_label);
-rare_fallthrough = rare_destination (NEXT_INSN (jump_insn));
-switch (rare_fallthrough - rare_dest)
-{
-case -2:
-return -1;
-case -1:
-return 0;
-case 0:
-break;
-case 1:
-return 1;
-case 2:
-return 2;
-}
-/* If we couldn't figure out what this jump was, assume it won't be
-taken.  This should be rare.  */
-if (condition == 0)
 return 0;
-/* Predict backward branches usually take, forward branches usually not.  If
-we don't know whether this is forward or backward, assume the branch
-will be taken, since most are.  */
-return (target_label == 0 || INSN_UID (jump_insn) > max_uid
-	  || INSN_UID (target_label) > max_uid
-	  || (uid_to_ruid[INSN_UID (jump_insn)]
-	      > uid_to_ruid[INSN_UID (target_label)]));
 }
 /* Return the condition under which INSN will branch to TARGET.  If TARGET
 is zero, return the condition under which INSN will return.  If INSN is
 an unconditional branch, return const_true_rtx.  If INSN isn't a simple
 type of jump, or it doesn't go to TARGET, return 0.  */
 static rtx
-get_branch_condition (rtx insn, rtx target)
+get_branch_condition (const rtx_insn *insn, rtx target)
 {
 rtx pat = PATTERN (insn);
 rtx src;
 if (condjump_in_parallel_p (insn))
 pat = XVECEXP (pat, 0, 0);
-if (GET_CODE (pat) == RETURN)
+if (ANY_RETURN_P (pat) && pat == target)
-return target == 0 ? const_true_rtx : 0;
+return const_true_rtx;
-else if (GET_CODE (pat) != SET || SET_DEST (pat) != pc_rtx)
+if (GET_CODE (pat) != SET || SET_DEST (pat) != pc_rtx)
 return 0;
 src = SET_SRC (pat);
-if (GET_CODE (src) == LABEL_REF && XEXP (src, 0) == target)
+if (GET_CODE (src) == LABEL_REF && label_ref_label (src) == target)
 return const_true_rtx;
 else if (GET_CODE (src) == IF_THEN_ELSE
-	   && ((target == 0 && GET_CODE (XEXP (src, 1)) == RETURN)
+	   && XEXP (src, 2) == pc_rtx
-	       || (GET_CODE (XEXP (src, 1)) == LABEL_REF
+	   && ((GET_CODE (XEXP (src, 1)) == LABEL_REF
-		   && XEXP (XEXP (src, 1), 0) == target))
+		&& label_ref_label (XEXP (src, 1)) == target)
-	   && XEXP (src, 2) == pc_rtx)
+	       || (ANY_RETURN_P (XEXP (src, 1)) && XEXP (src, 1) == target)))
 return XEXP (src, 0);
 else if (GET_CODE (src) == IF_THEN_ELSE
-	   && ((target == 0 && GET_CODE (XEXP (src, 2)) == RETURN)
+	   && XEXP (src, 1) == pc_rtx
-	       || (GET_CODE (XEXP (src, 2)) == LABEL_REF
+	   && ((GET_CODE (XEXP (src, 2)) == LABEL_REF
-		   && XEXP (XEXP (src, 2), 0) == target))
+		&& label_ref_label (XEXP (src, 2)) == target)
-	   && XEXP (src, 1) == pc_rtx)
+	       || (ANY_RETURN_P (XEXP (src, 2)) && XEXP (src, 2) == target)))
 {
 enum rtx_code rev;
 rev = reversed_comparison_code (XEXP (src, 0), insn);
 if (rev != UNKNOWN)
 	return gen_rtx_fmt_ee (rev, GET_MODE (XEXP (src, 0)),
 /* Return nonzero if CONDITION is more strict than the condition of
 INSN, i.e., if INSN will always branch if CONDITION is true.  */
 static int
-condition_dominates_p (rtx condition, rtx insn)
+condition_dominates_p (rtx condition, const rtx_insn *insn)
 {
 rtx other_condition = get_branch_condition (insn, JUMP_LABEL (insn));
 enum rtx_code code = GET_CODE (condition);
 enum rtx_code other_code;
 /* Return nonzero if redirecting JUMP to NEWLABEL does not invalidate
 any insns already in the delay slot of JUMP.  */
 static int
-redirect_with_delay_slots_safe_p (rtx jump, rtx newlabel, rtx seq)
+redirect_with_delay_slots_safe_p (rtx_insn *jump, rtx newlabel, rtx seq)
 {
 int flags, i;
-rtx pat = PATTERN (seq);
+rtx_sequence *pat = as_a <rtx_sequence *> (PATTERN (seq));
 /* Make sure all the delay slots of this jump would still
 be valid after threading the jump.  If they are still
 valid, then return nonzero.  */
 flags = get_jump_flags (jump, newlabel);
-for (i = 1; i < XVECLEN (pat, 0); i++)
+for (i = 1; i < pat->len (); i++)
 if (! (
-#ifdef ANNUL_IFFALSE_SLOTS
+#if ANNUL_IFFALSE_SLOTS
 	   (INSN_ANNULLED_BRANCH_P (jump)
-	    && INSN_FROM_TARGET_P (XVECEXP (pat, 0, i)))
+	    && INSN_FROM_TARGET_P (pat->insn (i)))
-	   ? eligible_for_annul_false (jump, i - 1,
+	   ? eligible_for_annul_false (jump, i - 1, pat->insn (i), flags) :
-				       XVECEXP (pat, 0, i), flags) :
 #endif
-#ifdef ANNUL_IFTRUE_SLOTS
+#if ANNUL_IFTRUE_SLOTS
 	   (INSN_ANNULLED_BRANCH_P (jump)
 	    && ! INSN_FROM_TARGET_P (XVECEXP (pat, 0, i)))
-	   ? eligible_for_annul_true (jump, i - 1,
+	   ? eligible_for_annul_true (jump, i - 1, pat->insn (i), flags) :
-				      XVECEXP (pat, 0, i), flags) :
 #endif
-	   eligible_for_delay (jump, i - 1, XVECEXP (pat, 0, i), flags)))
+	   eligible_for_delay (jump, i - 1, pat->insn (i), flags)))
 break;
-return (i == XVECLEN (pat, 0));
+return (i == pat->len ());
 }
 /* Return nonzero if redirecting JUMP to NEWLABEL does not invalidate
 any insns we wish to place in the delay slot of JUMP.  */
 static int
-redirect_with_delay_list_safe_p (rtx jump, rtx newlabel, rtx delay_list)
+redirect_with_delay_list_safe_p (rtx_insn *jump, rtx newlabel,
-{
+				 const vec<rtx_insn *> &delay_list)
-int flags, i;
+{
-rtx li;
 /* Make sure all the insns in DELAY_LIST would still be
 valid after threading the jump.  If they are still
 valid, then return nonzero.  */
-flags = get_jump_flags (jump, newlabel);
+int flags = get_jump_flags (jump, newlabel);
-for (li = delay_list, i = 0; li; li = XEXP (li, 1), i++)
+unsigned int delay_insns = delay_list.length ();
+unsigned int i = 0;
+for (; i < delay_insns; i++)
 if (! (
-#ifdef ANNUL_IFFALSE_SLOTS
+#if ANNUL_IFFALSE_SLOTS
 	   (INSN_ANNULLED_BRANCH_P (jump)
-	    && INSN_FROM_TARGET_P (XEXP (li, 0)))
+	    && INSN_FROM_TARGET_P (delay_list[i]))
-	   ? eligible_for_annul_false (jump, i, XEXP (li, 0), flags) :
+	   ? eligible_for_annul_false (jump, i, delay_list[i], flags) :
 #endif
-#ifdef ANNUL_IFTRUE_SLOTS
+#if ANNUL_IFTRUE_SLOTS
 	   (INSN_ANNULLED_BRANCH_P (jump)
-	    && ! INSN_FROM_TARGET_P (XEXP (li, 0)))
+	    && ! INSN_FROM_TARGET_P (delay_list[i]))
-	   ? eligible_for_annul_true (jump, i, XEXP (li, 0), flags) :
+	   ? eligible_for_annul_true (jump, i, delay_list[i], flags) :
 #endif
-	   eligible_for_delay (jump, i, XEXP (li, 0), flags)))
+	   eligible_for_delay (jump, i, delay_list[i], flags)))
 break;
-return (li == NULL);
+return i == delay_insns;
 }
 /* DELAY_LIST is a list of insns that have already been placed into delay
 slots.  See if all of them have the same annulling status as ANNUL_TRUE_P.
 If not, return 0; otherwise return 1.  */
 static int
-check_annul_list_true_false (int annul_true_p, rtx delay_list)
+check_annul_list_true_false (int annul_true_p,
-{
+			     const vec<rtx_insn *> &delay_list)
-rtx temp;
+{
+rtx_insn *trial;
-if (delay_list)
+unsigned int i;
-{
+FOR_EACH_VEC_ELT (delay_list, i, trial)
-for (temp = delay_list; temp; temp = XEXP (temp, 1))
+if ((annul_true_p && INSN_FROM_TARGET_P (trial))
-	{
+	|| (!annul_true_p && !INSN_FROM_TARGET_P (trial)))
-	  rtx trial = XEXP (temp, 0);
+return 0;
-	  if ((annul_true_p && INSN_FROM_TARGET_P (trial))
-	      || (!annul_true_p && !INSN_FROM_TARGET_P (trial)))
-	    return 0;
-	}
-}
 return 1;
 }
 /* INSN branches to an insn whose pattern SEQ is a SEQUENCE.  Given that
 it may set that value nonzero.
 PNEW_THREAD points to a location that is to receive the place at which
 execution should continue.  */
-static rtx
+static void
-steal_delay_list_from_target (rtx insn, rtx condition, rtx seq,
+steal_delay_list_from_target (rtx_insn *insn, rtx condition, rtx_sequence *seq,
-			      rtx delay_list, struct resources *sets,
+			      vec<rtx_insn *> *delay_list, resources *sets,
 			      struct resources *needed,
 			      struct resources *other_needed,
 			      int slots_to_fill, int *pslots_filled,
 			      int *pannul_p, rtx *pnew_thread)
 {
-rtx temp;
 int slots_remaining = slots_to_fill - *pslots_filled;
 int total_slots_filled = *pslots_filled;
-rtx new_delay_list = 0;
+auto_vec<rtx_insn *, 5> new_delay_list;
 int must_annul = *pannul_p;
 int used_annul = 0;
 int i;
 struct resources cc_set;
+bool *redundant;
 /* We can't do anything if there are more delay slots in SEQ than we
 can handle, or if we don't know that it will be a taken branch.
 We know that it will be a taken branch if it is either an unconditional
 branch or a conditional branch with a stricter branch condition.
 sequence is a conditional jump. We can not do this because we can
 not change the direction of the jump because the condition codes
 will effect the direction of the jump in the sequence.  */
 CLEAR_RESOURCE (&cc_set);
-for (temp = delay_list; temp; temp = XEXP (temp, 1))
-{
+rtx_insn *trial;
-rtx trial = XEXP (temp, 0);
+FOR_EACH_VEC_ELT (*delay_list, i, trial)
+{
 mark_set_resources (trial, &cc_set, 0, MARK_SRC_DEST_CALL);
-if (insn_references_resource_p (XVECEXP (seq , 0, 0), &cc_set, false))
+if (insn_references_resource_p (seq->insn (0), &cc_set, false))
-	return delay_list;
+	return;
 }
 if (XVECLEN (seq, 0) - 1 > slots_remaining
-|| ! condition_dominates_p (condition, XVECEXP (seq, 0, 0))
+|| ! condition_dominates_p (condition, seq->insn (0))
-|| ! single_set (XVECEXP (seq, 0, 0)))
+|| ! single_set (seq->insn (0)))
-return delay_list;
+return;
-#ifdef MD_CAN_REDIRECT_BRANCH
 /* On some targets, branches with delay slots can have a limited
 displacement.  Give the back end a chance to tell us we can't do
 this.  */
-if (! MD_CAN_REDIRECT_BRANCH (insn, XVECEXP (seq, 0, 0)))
+if (! targetm.can_follow_jump (insn, seq->insn (0)))
-return delay_list;
+return;
-#endif
+redundant = XALLOCAVEC (bool, XVECLEN (seq, 0));
-for (i = 1; i < XVECLEN (seq, 0); i++)
+for (i = 1; i < seq->len (); i++)
 {
-rtx trial = XVECEXP (seq, 0, i);
+rtx_insn *trial = seq->insn (i);
 int flags;
 if (insn_references_resource_p (trial, sets, false)
 	  || insn_sets_resource_p (trial, needed, false)
 	  || insn_sets_resource_p (trial, sets, false)
-#ifdef HAVE_cc0
 	  /* If TRIAL sets CC0, we can't copy it, so we can't steal this
 	     delay list.  */
-	  || find_reg_note (trial, REG_CC_USER, NULL_RTX)
+	  || (HAVE_cc0 && find_reg_note (trial, REG_CC_USER, NULL_RTX))
-#endif
 	  /* If TRIAL is from the fallthrough code of an annulled branch insn
 	     in SEQ, we cannot use it.  */
-	  || (INSN_ANNULLED_BRANCH_P (XVECEXP (seq, 0, 0))
+	  || (INSN_ANNULLED_BRANCH_P (seq->insn (0))
 	      && ! INSN_FROM_TARGET_P (trial)))
-	return delay_list;
+	return;
 /* If this insn was already done (usually in a previous delay slot),
 	 pretend we put it in our delay slot.  */
-if (redundant_insn (trial, insn, new_delay_list))
+redundant[i] = redundant_insn (trial, insn, new_delay_list);
+if (redundant[i])
 	continue;
 /* We will end up re-vectoring this branch, so compute flags
 	 based on jumping to the new label.  */
-flags = get_jump_flags (insn, JUMP_LABEL (XVECEXP (seq, 0, 0)));
+flags = get_jump_flags (insn, JUMP_LABEL (seq->insn (0)));
 if (! must_annul
 	  && ((condition == const_true_rtx
 	       || (! insn_sets_resource_p (trial, other_needed, false)
 		   && ! may_trap_or_fault_p (PATTERN (trial)))))
 	  ? eligible_for_delay (insn, total_slots_filled, trial, flags)
-	  : (must_annul || (delay_list == NULL && new_delay_list == NULL))
+	  : (must_annul || (delay_list->is_empty () && new_delay_list.is_empty ()))
 	     && (must_annul = 1,
-	         check_annul_list_true_false (0, delay_list)
+		 check_annul_list_true_false (0, *delay_list)
 	         && check_annul_list_true_false (0, new_delay_list)
 	         && eligible_for_annul_false (insn, total_slots_filled,
 					      trial, flags)))
 	{
 	  if (must_annul)
-	    used_annul = 1;
+	    {
-	  temp = copy_rtx (trial);
+	      /* Frame related instructions cannot go into annulled delay
+		 slots, it messes up the dwarf info.  */
+	      if (RTX_FRAME_RELATED_P (trial))
+		return;
+	      used_annul = 1;
+	    }
+	  rtx_insn *temp = copy_delay_slot_insn (trial);
 	  INSN_FROM_TARGET_P (temp) = 1;
-	  new_delay_list = add_to_delay_list (temp, new_delay_list);
+	  add_to_delay_list (temp, &new_delay_list);
 	  total_slots_filled++;
 	  if (--slots_remaining == 0)
 	    break;
 	}
 else
-	return delay_list;
+	return;
 }
+/* Record the effect of the instructions that were redundant and which
+we therefore decided not to copy.  */
+for (i = 1; i < seq->len (); i++)
+if (redundant[i])
+update_block (seq->insn (i), insn);
 /* Show the place to which we will be branching.  */
-*pnew_thread = next_active_insn (JUMP_LABEL (XVECEXP (seq, 0, 0)));
+*pnew_thread = first_active_target_insn (JUMP_LABEL (seq->insn (0)));
 /* Add any new insns to the delay list and update the count of the
 number of slots filled.  */
 *pslots_filled = total_slots_filled;
 if (used_annul)
 *pannul_p = 1;
-if (delay_list == 0)
+rtx_insn *temp;
-return new_delay_list;
+FOR_EACH_VEC_ELT (new_delay_list, i, temp)
+add_to_delay_list (temp, delay_list);
-for (temp = new_delay_list; temp; temp = XEXP (temp, 1))
-delay_list = add_to_delay_list (XEXP (temp, 0), delay_list);
-return delay_list;
 }
 /* Similar to steal_delay_list_from_target except that SEQ is on the
 fallthrough path of INSN.  Here we only do something if the delay insn
 of SEQ is an unconditional branch.  In that case we steal its delay slot
 for INSN since unconditional branches are much easier to fill.  */
-static rtx
+static void
-steal_delay_list_from_fallthrough (rtx insn, rtx condition, rtx seq,
+steal_delay_list_from_fallthrough (rtx_insn *insn, rtx condition,
-				   rtx delay_list, struct resources *sets,
+				   rtx_sequence *seq,
+				   vec<rtx_insn *> *delay_list,
+				   struct resources *sets,
 				   struct resources *needed,
 				   struct resources *other_needed,
 				   int slots_to_fill, int *pslots_filled,
 				   int *pannul_p)
 {
 flags = get_jump_flags (insn, JUMP_LABEL (insn));
 /* We can't do anything if SEQ's delay insn isn't an
 unconditional branch.  */
-if (! simplejump_p (XVECEXP (seq, 0, 0))
+if (! simplejump_or_return_p (seq->insn (0)))
-&& GET_CODE (PATTERN (XVECEXP (seq, 0, 0))) != RETURN)
+return;
-return delay_list;
+for (i = 1; i < seq->len (); i++)
-for (i = 1; i < XVECLEN (seq, 0); i++)
+{
-{
+rtx_insn *trial = seq->insn (i);
-rtx trial = XVECEXP (seq, 0, i);
 /* If TRIAL sets CC0, stealing it will move it too far from the use
 	 of CC0.  */
 if (insn_references_resource_p (trial, sets, false)
 	  || insn_sets_resource_p (trial, needed, false)
 	  || insn_sets_resource_p (trial, sets, false)
-#ifdef HAVE_cc0
+	  || (HAVE_cc0 && sets_cc0_p (PATTERN (trial))))
-	  || sets_cc0_p (PATTERN (trial))
-#endif
-	  )
 	break;
 /* If this insn was already done, we don't need it.  */
-if (redundant_insn (trial, insn, delay_list))
+if (redundant_insn (trial, insn, *delay_list))
 	{
+	  update_block (trial, insn);
 	  delete_from_delay_slot (trial);
 	  continue;
 	}
 if (! must_annul
 	  && ((condition == const_true_rtx
 	       || (! insn_sets_resource_p (trial, other_needed, false)
 		   && ! may_trap_or_fault_p (PATTERN (trial)))))
 	  ? eligible_for_delay (insn, *pslots_filled, trial, flags)
-	  : (must_annul || delay_list == NULL) && (must_annul = 1,
+	  : (must_annul || delay_list->is_empty ()) && (must_annul = 1,
-	     check_annul_list_true_false (1, delay_list)
+	     check_annul_list_true_false (1, *delay_list)
 	     && eligible_for_annul_true (insn, *pslots_filled, trial, flags)))
 	{
 	  if (must_annul)
 	    used_annul = 1;
 	  delete_from_delay_slot (trial);
-	  delay_list = add_to_delay_list (trial, delay_list);
+	  add_to_delay_list (trial, delay_list);
 	  if (++(*pslots_filled) == slots_to_fill)
 	    break;
 	}
 else
 	break;
 }
 if (used_annul)
 *pannul_p = 1;
-return delay_list;
 }
 /* Try merging insns starting at THREAD which match exactly the insns in
 INSN's delay list.
 For each insn that is merged, if the branch is or will be non-annulling,
 we delete the merged insn.  */
 static void
-try_merge_delay_insns (rtx insn, rtx thread)
+try_merge_delay_insns (rtx_insn *insn, rtx_insn *thread)
 {
-rtx trial, next_trial;
+rtx_insn *trial, *next_trial;
-rtx delay_insn = XVECEXP (PATTERN (insn), 0, 0);
+rtx_insn *delay_insn = as_a <rtx_insn *> (XVECEXP (PATTERN (insn), 0, 0));
-int annul_p = INSN_ANNULLED_BRANCH_P (delay_insn);
+int annul_p = JUMP_P (delay_insn) && INSN_ANNULLED_BRANCH_P (delay_insn);
 int slot_number = 1;
 int num_slots = XVECLEN (PATTERN (insn), 0);
 rtx next_to_match = XVECEXP (PATTERN (insn), 0, slot_number);
-struct resources set, needed;
+struct resources set, needed, modified;
-rtx merged_insns = 0;
+auto_vec<std::pair<rtx_insn *, bool>, 10> merged_insns;
-int i;
 int flags;
 flags = get_jump_flags (delay_insn, JUMP_LABEL (delay_insn));
 CLEAR_RESOURCE (&needed);
 folded into one.  If we are annulling, this would be the correct
 thing to do.  (The alternative, looking at things set in NEXT_TO_MATCH
 will essentially disable this optimization.  This method is somewhat of
 a kludge, but I don't see a better way.)  */
 if (! annul_p)
-for (i = 1 ; i < num_slots; i++)
+for (int i = 1; i < num_slots; i++)
 if (XVECEXP (PATTERN (insn), 0, i))
 	mark_referenced_resources (XVECEXP (PATTERN (insn), 0, i), &needed,
 				   true);
 for (trial = thread; !stop_search_p (trial, 1); trial = next_trial)
 if (NONJUMP_INSN_P (trial)
 	  && (GET_CODE (pat) == USE || GET_CODE (pat) == CLOBBER))
 	continue;
 if (GET_CODE (next_to_match) == GET_CODE (trial)
-#ifdef HAVE_cc0
 	  /* We can't share an insn that sets cc0.  */
-	  && ! sets_cc0_p (pat)
+	  && (!HAVE_cc0 || ! sets_cc0_p (pat))
-#endif
 	  && ! insn_references_resource_p (trial, &set, true)
 	  && ! insn_sets_resource_p (trial, &set, true)
 	  && ! insn_sets_resource_p (trial, &needed, true)
 	  && (trial = try_split (pat, trial, 0)) != 0
 	  /* Update next_trial, in case try_split succeeded.  */
 	      delete_related_insns (trial);
 	      INSN_FROM_TARGET_P (next_to_match) = 0;
 	    }
 	  else
-	    merged_insns = gen_rtx_INSN_LIST (VOIDmode, trial, merged_insns);
+	    merged_insns.safe_push (std::pair<rtx_insn *, bool> (trial, false));
 	  if (++slot_number == num_slots)
 	    break;
 	  next_to_match = XVECEXP (PATTERN (insn), 0, slot_number);
 /* See if we stopped on a filled insn.  If we did, try to see if its
 delay slots match.  */
 if (slot_number != num_slots
 && trial && NONJUMP_INSN_P (trial)
 && GET_CODE (PATTERN (trial)) == SEQUENCE
-&& ! INSN_ANNULLED_BRANCH_P (XVECEXP (PATTERN (trial), 0, 0)))
+&& !(JUMP_P (XVECEXP (PATTERN (trial), 0, 0))
-{
+&& INSN_ANNULLED_BRANCH_P (XVECEXP (PATTERN (trial), 0, 0))))
-rtx pat = PATTERN (trial);
+{
+rtx_sequence *pat = as_a <rtx_sequence *> (PATTERN (trial));
 rtx filled_insn = XVECEXP (pat, 0, 0);
 /* Account for resources set/needed by the filled insn.  */
 mark_set_resources (filled_insn, &set, 0, MARK_SRC_DEST_CALL);
 mark_referenced_resources (filled_insn, &needed, true);
-for (i = 1; i < XVECLEN (pat, 0); i++)
+for (int i = 1; i < pat->len (); i++)
 	{
-	  rtx dtrial = XVECEXP (pat, 0, i);
+	  rtx_insn *dtrial = pat->insn (i);
+	  CLEAR_RESOURCE (&modified);
+	  /* Account for resources set by the insn following NEXT_TO_MATCH
+	     inside INSN's delay list. */
+	  for (int j = 1; slot_number + j < num_slots; j++)
+	    mark_set_resources (XVECEXP (PATTERN (insn), 0, slot_number + j),
+				&modified, 0, MARK_SRC_DEST_CALL);
+	  /* Account for resources set by the insn before DTRIAL and inside
+	     TRIAL's delay list. */
+	  for (int j = 1; j < i; j++)
+	    mark_set_resources (XVECEXP (pat, 0, j),
+				&modified, 0, MARK_SRC_DEST_CALL);
 	  if (! insn_references_resource_p (dtrial, &set, true)
 	      && ! insn_sets_resource_p (dtrial, &set, true)
 	      && ! insn_sets_resource_p (dtrial, &needed, true)
-#ifdef HAVE_cc0
+	      && (!HAVE_cc0 || ! sets_cc0_p (PATTERN (dtrial)))
-	      && ! sets_cc0_p (PATTERN (dtrial))
-#endif
 	      && rtx_equal_p (PATTERN (next_to_match), PATTERN (dtrial))
+	      /* Check that DTRIAL and NEXT_TO_MATCH does not reference a
+	         resource modified between them (only dtrial is checked because
+	         next_to_match and dtrial shall to be equal in order to hit
+	         this line) */
+	      && ! insn_references_resource_p (dtrial, &modified, true)
 	      && eligible_for_delay (delay_insn, slot_number - 1, dtrial, flags))
 	    {
 	      if (! annul_p)
 		{
-		  rtx new_rtx;
+		  rtx_insn *new_rtx;
 		  update_block (dtrial, thread);
 		  new_rtx = delete_from_delay_slot (dtrial);
-	          if (INSN_DELETED_P (thread))
+	          if (thread->deleted ())
 		    thread = new_rtx;
 		  INSN_FROM_TARGET_P (next_to_match) = 0;
 		}
 	      else
-		merged_insns = gen_rtx_INSN_LIST (SImode, dtrial,
+		merged_insns.safe_push (std::pair<rtx_insn *, bool> (dtrial,
-						  merged_insns);
+								     true));
 	      if (++slot_number == num_slots)
 		break;
 	      next_to_match = XVECEXP (PATTERN (insn), 0, slot_number);
 merged insns.  Also clear the INSN_FROM_TARGET_P bit of each insn in
 the delay list so that we know that it isn't only being used at the
 target.  */
 if (slot_number == num_slots && annul_p)
 {
-for (; merged_insns; merged_insns = XEXP (merged_insns, 1))
+unsigned int len = merged_insns.length ();
-	{
+for (unsigned int i = len - 1; i < len; i--)
-	  if (GET_MODE (merged_insns) == SImode)
+	if (merged_insns[i].second)
-	    {
+	  {
-	      rtx new_rtx;
+	    update_block (merged_insns[i].first, thread);
+	    rtx_insn *new_rtx = delete_from_delay_slot (merged_insns[i].first);
-	      update_block (XEXP (merged_insns, 0), thread);
+	    if (thread->deleted ())
-	      new_rtx = delete_from_delay_slot (XEXP (merged_insns, 0));
+	      thread = new_rtx;
-	      if (INSN_DELETED_P (thread))
+	  }
-		thread = new_rtx;
+	else
-	    }
+	  {
-	  else
+	    update_block (merged_insns[i].first, thread);
-	    {
+	    delete_related_insns (merged_insns[i].first);
-	      update_block (XEXP (merged_insns, 0), thread);
+	  }
-	      delete_related_insns (XEXP (merged_insns, 0));
-	    }
-	}
 INSN_ANNULLED_BRANCH_P (delay_insn) = 0;
-for (i = 0; i < XVECLEN (PATTERN (insn), 0); i++)
+for (int i = 0; i < XVECLEN (PATTERN (insn), 0); i++)
 	INSN_FROM_TARGET_P (XVECEXP (PATTERN (insn), 0, i)) = 0;
 }
 }
 /* See if INSN is redundant with an insn in front of TARGET.  Often this
 We do not split insns we encounter.  This could cause us not to find a
 redundant insn, but the cost of splitting seems greater than the possible
 gain in rare cases.  */
-static rtx
+static rtx_insn *
-redundant_insn (rtx insn, rtx target, rtx delay_list)
+redundant_insn (rtx insn, rtx_insn *target, const vec<rtx_insn *> &delay_list)
 {
 rtx target_main = target;
 rtx ipat = PATTERN (insn);
-rtx trial, pat;
+rtx_insn *trial;
+rtx pat;
 struct resources needed, set;
 int i;
 unsigned insns_to_search;
 /* If INSN has any REG_UNUSED notes, it can't match anything since we
 for (trial = PREV_INSN (target),
 	 insns_to_search = MAX_DELAY_SLOT_INSN_SEARCH;
 trial && insns_to_search > 0;
 trial = PREV_INSN (trial))
 {
-if (LABEL_P (trial))
+/* (use (insn))s can come immediately after a barrier if the
+	 label that used to precede them has been deleted as dead.
+	 See delete_related_insns.  */
+if (LABEL_P (trial) || BARRIER_P (trial))
 	return 0;
-if (!NONDEBUG_INSN_P (trial))
+if (!INSN_P (trial))
 	continue;
 --insns_to_search;
 pat = PATTERN (trial);
 if (GET_CODE (pat) == USE || GET_CODE (pat) == CLOBBER)
 	continue;
-if (GET_CODE (pat) == SEQUENCE)
+if (rtx_sequence *seq = dyn_cast <rtx_sequence *> (pat))
 	{
 	  /* Stop for a CALL and its delay slots because it is difficult to
 	     track its resource needs correctly.  */
-	  if (CALL_P (XVECEXP (pat, 0, 0)))
+	  if (CALL_P (seq->element (0)))
 	    return 0;
 	  /* Stop for an INSN or JUMP_INSN with delayed effects and its delay
 	     slots because it is difficult to track its resource needs
 	     correctly.  */
-#ifdef INSN_SETS_ARE_DELAYED
+	  if (INSN_SETS_ARE_DELAYED (seq->insn (0)))
-	  if (INSN_SETS_ARE_DELAYED (XVECEXP (pat, 0, 0)))
 	    return 0;
-#endif
+	  if (INSN_REFERENCES_ARE_DELAYED (seq->insn (0)))
-#ifdef INSN_REFERENCES_ARE_DELAYED
-	  if (INSN_REFERENCES_ARE_DELAYED (XVECEXP (pat, 0, 0)))
 	    return 0;
-#endif
 	  /* See if any of the insns in the delay slot match, updating
 	     resource requirements as we go.  */
-	  for (i = XVECLEN (pat, 0) - 1; i > 0; i--)
+	  for (i = seq->len () - 1; i > 0; i--)
-	    if (GET_CODE (XVECEXP (pat, 0, i)) == GET_CODE (insn)
+	    if (GET_CODE (seq->element (i)) == GET_CODE (insn)
-		&& rtx_equal_p (PATTERN (XVECEXP (pat, 0, i)), ipat)
+		&& rtx_equal_p (PATTERN (seq->element (i)), ipat)
-		&& ! find_reg_note (XVECEXP (pat, 0, i), REG_UNUSED, NULL_RTX))
+		&& ! find_reg_note (seq->element (i), REG_UNUSED, NULL_RTX))
 	      break;
 	  /* If found a match, exit this loop early.  */
 	  if (i > 0)
 	    break;
 /* If TARGET is a SEQUENCE, get the main insn.  */
 if (NONJUMP_INSN_P (target) && GET_CODE (PATTERN (target)) == SEQUENCE)
 target_main = XVECEXP (PATTERN (target), 0, 0);
 if (resource_conflicts_p (&needed, &set)
-#ifdef HAVE_cc0
+|| (HAVE_cc0 && reg_mentioned_p (cc0_rtx, ipat))
-|| reg_mentioned_p (cc0_rtx, ipat)
-#endif
 /* The insn requiring the delay may not set anything needed or set by
 	 INSN.  */
 || insn_sets_resource_p (target_main, &needed, true)
 || insn_sets_resource_p (target_main, &set, true))
 return 0;
 /* Insns we pass may not set either NEEDED or SET, so merge them for
 simpler tests.  */
 needed.memory |= set.memory;
-needed.unch_memory |= set.unch_memory;
 IOR_HARD_REG_SET (needed.regs, set.regs);
 /* This insn isn't redundant if it conflicts with an insn that either is
 or will be in a delay slot of TARGET.  */
-while (delay_list)
+unsigned int j;
-{
+rtx_insn *temp;
-if (insn_sets_resource_p (XEXP (delay_list, 0), &needed, true))
+FOR_EACH_VEC_ELT (delay_list, j, temp)
-	return 0;
+if (insn_sets_resource_p (temp, &needed, true))
-delay_list = XEXP (delay_list, 1);
+return 0;
-}
 if (NONJUMP_INSN_P (target) && GET_CODE (PATTERN (target)) == SEQUENCE)
 for (i = 1; i < XVECLEN (PATTERN (target), 0); i++)
 if (insn_sets_resource_p (XVECEXP (PATTERN (target), 0, i), &needed,
 				true))
 for (trial = PREV_INSN (target),
 	 insns_to_search = MAX_DELAY_SLOT_INSN_SEARCH;
 trial && !LABEL_P (trial) && insns_to_search > 0;
 trial = PREV_INSN (trial))
 {
-if (!NONDEBUG_INSN_P (trial))
+if (!INSN_P (trial))
 	continue;
 --insns_to_search;
 pat = PATTERN (trial);
 if (GET_CODE (pat) == USE || GET_CODE (pat) == CLOBBER)
 	continue;
-if (GET_CODE (pat) == SEQUENCE)
+if (rtx_sequence *seq = dyn_cast <rtx_sequence *> (pat))
 	{
+	  bool annul_p = false;
+rtx_insn *control = seq->insn (0);
 	  /* If this is a CALL_INSN and its delay slots, it is hard to track
 	     the resource needs properly, so give up.  */
-	  if (CALL_P (XVECEXP (pat, 0, 0)))
+	  if (CALL_P (control))
 	    return 0;
 	  /* If this is an INSN or JUMP_INSN with delayed effects, it
 	     is hard to track the resource needs properly, so give up.  */
-#ifdef INSN_SETS_ARE_DELAYED
+	  if (INSN_SETS_ARE_DELAYED (control))
-	  if (INSN_SETS_ARE_DELAYED (XVECEXP (pat, 0, 0)))
 	    return 0;
-#endif
+	  if (INSN_REFERENCES_ARE_DELAYED (control))
-#ifdef INSN_REFERENCES_ARE_DELAYED
-	  if (INSN_REFERENCES_ARE_DELAYED (XVECEXP (pat, 0, 0)))
 	    return 0;
-#endif
+	  if (JUMP_P (control))
+	    annul_p = INSN_ANNULLED_BRANCH_P (control);
 	  /* See if any of the insns in the delay slot match, updating
 	     resource requirements as we go.  */
-	  for (i = XVECLEN (pat, 0) - 1; i > 0; i--)
+	  for (i = seq->len () - 1; i > 0; i--)
 	    {
-	      rtx candidate = XVECEXP (pat, 0, i);
+	      rtx_insn *candidate = seq->insn (i);
 	      /* If an insn will be annulled if the branch is false, it isn't
 		 considered as a possible duplicate insn.  */
 	      if (rtx_equal_p (PATTERN (candidate), ipat)
-		  && ! (INSN_ANNULLED_BRANCH_P (XVECEXP (pat, 0, 0))
+		  && ! (annul_p && INSN_FROM_TARGET_P (candidate)))
-			&& INSN_FROM_TARGET_P (candidate)))
 		{
 		  /* Show that this insn will be used in the sequel.  */
 		  INSN_FROM_TARGET_P (candidate) = 0;
 		  return candidate;
 		}
 	      /* Unless this is an annulled insn from the target of a branch,
 		 we must stop if it sets anything needed or set by INSN.  */
-	      if ((! INSN_ANNULLED_BRANCH_P (XVECEXP (pat, 0, 0))
+	      if ((!annul_p || !INSN_FROM_TARGET_P (candidate))
-		   || ! INSN_FROM_TARGET_P (candidate))
 		  && insn_sets_resource_p (candidate, &needed, true))
 		return 0;
 	    }
 	  /* If the insn requiring the delay slot conflicts with INSN, we
 	     must stop.  */
-	  if (insn_sets_resource_p (XVECEXP (pat, 0, 0), &needed, true))
+	  if (insn_sets_resource_p (control, &needed, true))
 	    return 0;
 	}
 else
 	{
 	  /* See if TRIAL is the same as INSN.  */
 finding an active insn, we do not own this thread.  */
 static int
 own_thread_p (rtx thread, rtx label, int allow_fallthrough)
 {
-rtx active_insn;
+rtx_insn *active_insn;
-rtx insn;
+rtx_insn *insn;
 /* We don't own the function end.  */
-if (thread == 0)
+if (thread == 0 || ANY_RETURN_P (thread))
 return 0;
-/* Get the first active insn, or THREAD, if it is an active insn.  */
+/* We have a non-NULL insn.  */
-active_insn = next_active_insn (PREV_INSN (thread));
+rtx_insn *thread_insn = as_a <rtx_insn *> (thread);
-for (insn = thread; insn != active_insn; insn = NEXT_INSN (insn))
+/* Get the first active insn, or THREAD_INSN, if it is an active insn.  */
+active_insn = next_active_insn (PREV_INSN (thread_insn));
+for (insn = thread_insn; insn != active_insn; insn = NEXT_INSN (insn))
 if (LABEL_P (insn)
 	&& (insn != label || LABEL_NUSES (insn) != 1))
 return 0;
 if (allow_fallthrough)
 return 1;
 /* Ensure that we reach a BARRIER before any insn or label.  */
-for (insn = prev_nonnote_insn (thread);
+for (insn = prev_nonnote_insn (thread_insn);
 insn == 0 || !BARRIER_P (insn);
 insn = prev_nonnote_insn (insn))
 if (insn == 0
 	|| LABEL_P (insn)
 	|| (NONJUMP_INSN_P (insn)
 return 1;
 }
 /* Called when INSN is being moved from a location near the target of a jump.
-We leave a marker of the form (use (INSN)) immediately in front
+We leave a marker of the form (use (INSN)) immediately in front of WHERE
-of WHERE for mark_target_live_regs.  These markers will be deleted when
+for mark_target_live_regs.  These markers will be deleted at the end.
-reorg finishes.
 We used to try to update the live status of registers if WHERE is at
 the start of a basic block, but that can't work since we may remove a
 BARRIER in relax_delay_slots.  */
 static void
-update_block (rtx insn, rtx where)
+update_block (rtx_insn *insn, rtx_insn *where)
 {
-/* Ignore if this was in a delay slot and it came from the target of
-a branch.  */
-if (INSN_FROM_TARGET_P (insn))
-return;
 emit_insn_before (gen_rtx_USE (VOIDmode, insn), where);
 /* INSN might be making a value live in a block where it didn't use to
 be.  So recompute liveness information for this block.  */
 incr_ticks_for_insn (insn);
 }
 /* Similar to REDIRECT_JUMP except that we update the BB_TICKS entry for
 the basic block containing the jump.  */
 static int
-reorg_redirect_jump (rtx jump, rtx nlabel)
+reorg_redirect_jump (rtx_jump_insn *jump, rtx nlabel)
 {
 incr_ticks_for_insn (jump);
 return redirect_jump (jump, nlabel, 1);
 }
 gets moved before a CODE_LABEL because it is a redundant insn.  In this
 case, mark_target_live_regs may be confused into thinking the register
 is dead because it sees a REG_DEAD note immediately before a CODE_LABEL.  */
 static void
-update_reg_dead_notes (rtx insn, rtx delayed_insn)
+update_reg_dead_notes (rtx_insn *insn, rtx_insn *delayed_insn)
 {
-rtx p, link, next;
+rtx link, next;
+rtx_insn *p;
 for (p = next_nonnote_insn (insn); p != delayed_insn;
 p = next_nonnote_insn (p))
 for (link = REG_NOTES (p); link; link = next)
 {
 If the REG_DEAD note isn't deleted, then mark_target_live_regs may be
 confused into thinking the register is dead.  */
 static void
-fix_reg_dead_note (rtx start_insn, rtx stop_insn)
+fix_reg_dead_note (rtx_insn *start_insn, rtx stop_insn)
 {
-rtx p, link, next;
+rtx link, next;
+rtx_insn *p;
 for (p = next_nonnote_insn (start_insn); p != stop_insn;
 p = next_nonnote_insn (p))
 for (link = REG_NOTES (p); link; link = next)
 {
 output depending on whether any REG_UNUSED notes are present.
 we must make sure that INSN calculates as many results as REDUNDANT_INSN
 does.  */
 static void
-update_reg_unused_notes (rtx insn, rtx redundant_insn)
+update_reg_unused_notes (rtx_insn *insn, rtx redundant_insn)
 {
 rtx link, next;
 for (link = REG_NOTES (insn); link; link = next)
 {
 			     REGNO (XEXP (link, 0))))
 	remove_note (insn, link);
 }
 }
-/* Return the label before INSN, or put a new label there.  */
+static vec <rtx> sibling_labels;
-static rtx
+/* Return the label before INSN, or put a new label there.  If SIBLING is
-get_label_before (rtx insn)
+non-zero, it is another label associated with the new label (if any),
-{
+typically the former target of the jump that will be redirected to
-rtx label;
+the new label.  */
+static rtx_insn *
+get_label_before (rtx_insn *insn, rtx sibling)
+{
+rtx_insn *label;
 /* Find an existing label at this point
 or make a new one if there is none.  */
 label = prev_nonnote_insn (insn);
 if (label == 0 || !LABEL_P (label))
 {
-rtx prev = PREV_INSN (insn);
+rtx_insn *prev = PREV_INSN (insn);
 label = gen_label_rtx ();
 emit_label_after (label, prev);
 LABEL_NUSES (label) = 0;
+if (sibling)
+	{
+	  sibling_labels.safe_push (label);
+	  sibling_labels.safe_push (sibling);
+	}
 }
 return label;
 }
 /* Scan a function looking for insns that need a delay slot and find insns to
 through FINAL_SEQUENCE.  */
 static void
 fill_simple_delay_slots (int non_jumps_p)
 {
-rtx insn, pat, trial, next_trial;
+rtx_insn *insn, *trial, *next_trial;
+rtx pat;
 int i;
 int num_unfilled_slots = unfilled_slots_next - unfilled_slots_base;
 struct resources needed, set;
 int slots_to_fill, slots_filled;
-rtx delay_list;
+auto_vec<rtx_insn *, 5> delay_list;
 for (i = 0; i < num_unfilled_slots; i++)
 {
 int flags;
 /* Get the next insn to fill.  If it has already had any slots assigned,
 	 we can't do anything with it.  Maybe we'll improve this later.  */
 insn = unfilled_slots_base[i];
 if (insn == 0
-	  || INSN_DELETED_P (insn)
+	  || insn->deleted ()
 	  || (NONJUMP_INSN_P (insn)
 	      && GET_CODE (PATTERN (insn)) == SEQUENCE)
 	  || (JUMP_P (insn) && non_jumps_p)
 	  || (!JUMP_P (insn) && ! non_jumps_p))
 	continue;
 	 This is tried on each insn with delay slots as some machines
 	 have insns which perform calls, but are not represented as
 	 CALL_INSNs.  */
 slots_filled = 0;
-delay_list = 0;
+delay_list.truncate (0);
 if (JUMP_P (insn))
 	flags = get_jump_flags (insn, JUMP_LABEL (insn));
 else
 	flags = get_jump_flags (insn, NULL_RTX);
 	  && simplejump_p (trial)
 	  && eligible_for_delay (insn, slots_filled, trial, flags)
 	  && no_labels_between_p (insn, trial)
 	  && ! can_throw_internal (trial))
 	{
-	  rtx *tmp;
+	  rtx_insn **tmp;
 	  slots_filled++;
-	  delay_list = add_to_delay_list (trial, delay_list);
+	  add_to_delay_list (trial, &delay_list);
 	  /* TRIAL may have had its delay slot filled, then unfilled.  When
 	     the delay slot is unfilled, TRIAL is placed back on the unfilled
 	     slots obstack.  Unfortunately, it is placed on the end of the
 	     obstack, not in its original location.  Therefore, we must search
 	  /* Remove the unconditional jump from consideration for delay slot
 	     filling and unthread it.  */
 	  if (*tmp == trial)
 	    *tmp = 0;
 	  {
-	    rtx next = NEXT_INSN (trial);
+	    rtx_insn *next = NEXT_INSN (trial);
-	    rtx prev = PREV_INSN (trial);
+	    rtx_insn *prev = PREV_INSN (trial);
 	    if (prev)
-	      NEXT_INSN (prev) = next;
+	      SET_NEXT_INSN (prev) = next;
 	    if (next)
-	      PREV_INSN (next) = prev;
+	      SET_PREV_INSN (next) = prev;
 	  }
 	}
 /* Now, scan backwards from the insn to search for a potential
 	 delay-slot candidate.  Stop searching when a label or jump is hit.
 	 (in which case the called routine, not the insn itself, is doing
 	 the setting).  */
 if (slots_filled < slots_to_fill)
 	{
+	  /* If the flags register is dead after the insn, then we want to be
+	     able to accept a candidate that clobbers it.  For this purpose,
+	     we need to filter the flags register during life analysis, so
+	     that it doesn't create RAW and WAW dependencies, while still
+	     creating the necessary WAR dependencies.  */
+	  bool filter_flags
+	    = (slots_to_fill == 1
+	       && targetm.flags_regnum != INVALID_REGNUM
+	       && find_regno_note (insn, REG_DEAD, targetm.flags_regnum));
+	  struct resources fset;
 	  CLEAR_RESOURCE (&needed);
 	  CLEAR_RESOURCE (&set);
 	  mark_set_resources (insn, &set, 0, MARK_SRC_DEST);
+	  if (filter_flags)
+	    {
+	      CLEAR_RESOURCE (&fset);
+	      mark_set_resources (insn, &fset, 0, MARK_SRC_DEST);
+	    }
 	  mark_referenced_resources (insn, &needed, false);
 	  for (trial = prev_nonnote_insn (insn); ! stop_search_p (trial, 1);
 	       trial = next_trial)
 	    {
 	      next_trial = prev_nonnote_insn (trial);
 	      /* This must be an INSN or CALL_INSN.  */
 	      pat = PATTERN (trial);
-	      /* USE and CLOBBER at this level was just for flow; ignore it.  */
+	      /* Stand-alone USE and CLOBBER are just for flow.  */
 	      if (GET_CODE (pat) == USE || GET_CODE (pat) == CLOBBER)
 		continue;
 	      /* Check for resource conflict first, to avoid unnecessary
 		 splitting.  */
 	      if (! insn_references_resource_p (trial, &set, true)
-		  && ! insn_sets_resource_p (trial, &set, true)
+		  && ! insn_sets_resource_p (trial,
+					     filter_flags ? &fset : &set,
+					     true)
 		  && ! insn_sets_resource_p (trial, &needed, true)
-#ifdef HAVE_cc0
 		  /* Can't separate set of cc0 from its use.  */
-		  && ! (reg_mentioned_p (cc0_rtx, pat) && ! sets_cc0_p (pat))
+		  && (!HAVE_cc0 || ! (reg_mentioned_p (cc0_rtx, pat) && ! sets_cc0_p (pat)))
-#endif
 		  && ! can_throw_internal (trial))
 		{
 		  trial = try_split (pat, trial, 1);
 		  next_trial = prev_nonnote_insn (trial);
 		  if (eligible_for_delay (insn, slots_filled, trial, flags))
 			 find insns to put on the delay list, we want
 			 to put them at the head, rather than the
 			 tail, of the list.  */
 		      update_reg_dead_notes (trial, insn);
-		      delay_list = gen_rtx_INSN_LIST (VOIDmode,
+		      delay_list.safe_insert (0, trial);
-						      trial, delay_list);
 		      update_block (trial, trial);
 		      delete_related_insns (trial);
 		      if (slots_to_fill == ++slots_filled)
 			break;
 		      continue;
 		    }
 		}
 	      mark_set_resources (trial, &set, 0, MARK_SRC_DEST_CALL);
+	      if (filter_flags)
+		{
+		  mark_set_resources (trial, &fset, 0, MARK_SRC_DEST_CALL);
+		  /* If the flags register is set, then it doesn't create RAW
+		     dependencies any longer and it also doesn't create WAW
+		     dependencies since it's dead after the original insn.  */
+		  if (TEST_HARD_REG_BIT (fset.regs, targetm.flags_regnum))
+		    {
+		      CLEAR_HARD_REG_BIT (needed.regs, targetm.flags_regnum);
+		      CLEAR_HARD_REG_BIT (fset.regs, targetm.flags_regnum);
+		    }
+		}
 	      mark_referenced_resources (trial, &needed, true);
 	    }
 	}
 /* If all needed slots haven't been filled, we come here.  */
 /* Try to optimize case of jumping around a single insn.  */
-#if defined(ANNUL_IFFALSE_SLOTS) || defined(ANNUL_IFTRUE_SLOTS)
+if ((ANNUL_IFTRUE_SLOTS || ANNUL_IFFALSE_SLOTS)
-if (slots_filled != slots_to_fill
+	&& slots_filled != slots_to_fill
-	  && delay_list == 0
+	  && delay_list.is_empty ()
 	  && JUMP_P (insn)
-	  && (condjump_p (insn) || condjump_in_parallel_p (insn)))
+	  && (condjump_p (insn) || condjump_in_parallel_p (insn))
-	{
+	  && !ANY_RETURN_P (JUMP_LABEL (insn)))
-	  delay_list = optimize_skip (insn);
+	{
-	  if (delay_list)
+	  optimize_skip (as_a <rtx_jump_insn *> (insn), &delay_list);
+	  if (!delay_list.is_empty ())
 	    slots_filled += 1;
 	}
-#endif
 /* Try to get insns from beyond the insn needing the delay slot.
 	 These insns can neither set or reference resources set in insns being
 	 skipped, cannot set resources in the insn being skipped, and, if this
 	 is a CALL_INSN (or a CALL_INSN is passed), cannot trap (because the
 	     exception.
 	     Presumably, we should also check to see if we could get
 	     back to this function via `setjmp'.  */
 	  && ! can_throw_internal (insn)
-	  && (!JUMP_P (insn)
+	  && !JUMP_P (insn))
-	      || ((condjump_p (insn) || condjump_in_parallel_p (insn))
+	{
-		  && ! simplejump_p (insn)
-		  && JUMP_LABEL (insn) != 0)))
-	{
-	  /* Invariant: If insn is a JUMP_INSN, the insn's jump
-	     label.  Otherwise, zero.  */
-	  rtx target = 0;
 	  int maybe_never = 0;
 	  rtx pat, trial_delay;
 	  CLEAR_RESOURCE (&needed);
 	  CLEAR_RESOURCE (&set);
+	  mark_set_resources (insn, &set, 0, MARK_SRC_DEST_CALL);
+	  mark_referenced_resources (insn, &needed, true);
 	  if (CALL_P (insn))
+	    maybe_never = 1;
+	  for (trial = next_nonnote_insn (insn); !stop_search_p (trial, 1);
+	       trial = next_trial)
 	    {
-	      mark_set_resources (insn, &set, 0, MARK_SRC_DEST_CALL);
+	      next_trial = next_nonnote_insn (trial);
-	      mark_referenced_resources (insn, &needed, true);
-	      maybe_never = 1;
+	      /* This must be an INSN or CALL_INSN.  */
+	      pat = PATTERN (trial);
+	      /* Stand-alone USE and CLOBBER are just for flow.  */
+	      if (GET_CODE (pat) == USE || GET_CODE (pat) == CLOBBER)
+		continue;
+	      /* If this already has filled delay slots, get the insn needing
+		 the delay slots.  */
+	      if (GET_CODE (pat) == SEQUENCE)
+		trial_delay = XVECEXP (pat, 0, 0);
+	      else
+		trial_delay = trial;
+	      /* Stop our search when seeing a jump.  */
+	      if (JUMP_P (trial_delay))
+		break;
+	      /* See if we have a resource problem before we try to split.  */
+	      if (GET_CODE (pat) != SEQUENCE
+		  && ! insn_references_resource_p (trial, &set, true)
+		  && ! insn_sets_resource_p (trial, &set, true)
+		  && ! insn_sets_resource_p (trial, &needed, true)
+		  && (!HAVE_cc0 && ! (reg_mentioned_p (cc0_rtx, pat) && ! sets_cc0_p (pat)))
+		  && ! (maybe_never && may_trap_or_fault_p (pat))
+		  && (trial = try_split (pat, trial, 0))
+		  && eligible_for_delay (insn, slots_filled, trial, flags)
+		  && ! can_throw_internal (trial))
+		{
+		  next_trial = next_nonnote_insn (trial);
+		  add_to_delay_list (trial, &delay_list);
+		  if (HAVE_cc0 && reg_mentioned_p (cc0_rtx, pat))
+		    link_cc0_insns (trial);
+		  delete_related_insns (trial);
+		  if (slots_to_fill == ++slots_filled)
+		    break;
+		  continue;
+		}
+	      mark_set_resources (trial, &set, 0, MARK_SRC_DEST_CALL);
+	      mark_referenced_resources (trial, &needed, true);
+	      /* Ensure we don't put insns between the setting of cc and the
+		 comparison by moving a setting of cc into an earlier delay
+		 slot since these insns could clobber the condition code.  */
+	      set.cc = 1;
+	      /* If this is a call, we might not get here.  */
+	      if (CALL_P (trial_delay))
+		maybe_never = 1;
 	    }
-	  else
-	    {
-	      mark_set_resources (insn, &set, 0, MARK_SRC_DEST_CALL);
-	      mark_referenced_resources (insn, &needed, true);
-	      if (JUMP_P (insn))
-		target = JUMP_LABEL (insn);
-	    }
-	  if (target == 0)
-	    for (trial = next_nonnote_insn (insn); trial; trial = next_trial)
-	      {
-		next_trial = next_nonnote_insn (trial);
-		if (LABEL_P (trial)
-		    || BARRIER_P (trial))
-		  break;
-		/* We must have an INSN, JUMP_INSN, or CALL_INSN.  */
-		pat = PATTERN (trial);
-		/* Stand-alone USE and CLOBBER are just for flow.  */
-		if (GET_CODE (pat) == USE || GET_CODE (pat) == CLOBBER)
-		  continue;
-		/* If this already has filled delay slots, get the insn needing
-		   the delay slots.  */
-		if (GET_CODE (pat) == SEQUENCE)
-		  trial_delay = XVECEXP (pat, 0, 0);
-		else
-		  trial_delay = trial;
-		/* Stop our search when seeing an unconditional jump.  */
-		if (JUMP_P (trial_delay))
-		  break;
-		/* See if we have a resource problem before we try to
-		   split.  */
-		if (GET_CODE (pat) != SEQUENCE
-		    && ! insn_references_resource_p (trial, &set, true)
-		    && ! insn_sets_resource_p (trial, &set, true)
-		    && ! insn_sets_resource_p (trial, &needed, true)
-#ifdef HAVE_cc0
-		    && ! (reg_mentioned_p (cc0_rtx, pat) && ! sets_cc0_p (pat))
-#endif
-		    && ! (maybe_never && may_trap_or_fault_p (pat))
-		    && (trial = try_split (pat, trial, 0))
-		    && eligible_for_delay (insn, slots_filled, trial, flags)
-		    && ! can_throw_internal(trial))
-		  {
-		    next_trial = next_nonnote_insn (trial);
-		    delay_list = add_to_delay_list (trial, delay_list);
-#ifdef HAVE_cc0
-		    if (reg_mentioned_p (cc0_rtx, pat))
-		      link_cc0_insns (trial);
-#endif
-		    delete_related_insns (trial);
-		    if (slots_to_fill == ++slots_filled)
-		      break;
-		    continue;
-		  }
-		mark_set_resources (trial, &set, 0, MARK_SRC_DEST_CALL);
-		mark_referenced_resources (trial, &needed, true);
-		/* Ensure we don't put insns between the setting of cc and the
-		   comparison by moving a setting of cc into an earlier delay
-		   slot since these insns could clobber the condition code.  */
-		set.cc = 1;
-		/* If this is a call or jump, we might not get here.  */
-		if (CALL_P (trial_delay)
-		    || JUMP_P (trial_delay))
-		  maybe_never = 1;
-	      }
 	  /* If there are slots left to fill and our search was stopped by an
 	     unconditional branch, try the insn at the branch target.  We can
 	     redirect the branch if it works.
 	     Don't do this if the insn at the branch target is a branch.  */
 	  if (slots_to_fill != slots_filled
 	      && trial
-	      && JUMP_P (trial)
+	      && jump_to_label_p (trial)
 	      && simplejump_p (trial)
-	      && (target == 0 || JUMP_LABEL (trial) == target)
+	      && (next_trial = next_active_insn (JUMP_LABEL_AS_INSN (trial))) != 0
-	      && (next_trial = next_active_insn (JUMP_LABEL (trial))) != 0
 	      && ! (NONJUMP_INSN_P (next_trial)
 		    && GET_CODE (PATTERN (next_trial)) == SEQUENCE)
 	      && !JUMP_P (next_trial)
 	      && ! insn_references_resource_p (next_trial, &set, true)
 	      && ! insn_sets_resource_p (next_trial, &set, true)
 	      && ! insn_sets_resource_p (next_trial, &needed, true)
-#ifdef HAVE_cc0
+	      && (!HAVE_cc0 || ! reg_mentioned_p (cc0_rtx, PATTERN (next_trial)))
-	      && ! reg_mentioned_p (cc0_rtx, PATTERN (next_trial))
-#endif
 	      && ! (maybe_never && may_trap_or_fault_p (PATTERN (next_trial)))
 	      && (next_trial = try_split (PATTERN (next_trial), next_trial, 0))
 	      && eligible_for_delay (insn, slots_filled, next_trial, flags)
 	      && ! can_throw_internal (trial))
 	    {
 	      /* See comment in relax_delay_slots about necessity of using
 		 next_real_insn here.  */
-	      rtx new_label = next_real_insn (next_trial);
+	      rtx_insn *new_label = next_real_insn (next_trial);
 	      if (new_label != 0)
-		new_label = get_label_before (new_label);
+		new_label = get_label_before (new_label, JUMP_LABEL (trial));
 	      else
-		new_label = find_end_label ();
+		new_label = find_end_label (simple_return_rtx);
 	      if (new_label)
 	        {
-		  delay_list
+		  add_to_delay_list (copy_delay_slot_insn (next_trial),
-		    = add_to_delay_list (copy_rtx (next_trial), delay_list);
+				     &delay_list);
 		  slots_filled++;
-		  reorg_redirect_jump (trial, new_label);
+		  reorg_redirect_jump (as_a <rtx_jump_insn *> (trial),
+				       new_label);
-		  /* If we merged because we both jumped to the same place,
-		     redirect the original insn also.  */
-		  if (target)
-		    reorg_redirect_jump (insn, new_label);
 		}
 	    }
 	}
 /* If this is an unconditional jump, then try to get insns from the
 	 target of the jump.  */
-if (JUMP_P (insn)
+rtx_jump_insn *jump_insn;
-	  && simplejump_p (insn)
+if ((jump_insn = dyn_cast <rtx_jump_insn *> (insn))
+	  && simplejump_p (jump_insn)
 	  && slots_filled != slots_to_fill)
-	delay_list
+	fill_slots_from_thread (jump_insn, const_true_rtx,
-	  = fill_slots_from_thread (insn, const_true_rtx,
+				next_active_insn (JUMP_LABEL_AS_INSN (insn)),
-				    next_active_insn (JUMP_LABEL (insn)),
+				NULL, 1, 1, own_thread_p (JUMP_LABEL (insn),
-				    NULL, 1, 1,
+						 JUMP_LABEL (insn), 0),
-				    own_thread_p (JUMP_LABEL (insn),
+				slots_to_fill, &slots_filled, &delay_list);
-						  JUMP_LABEL (insn), 0),
-				    slots_to_fill, &slots_filled,
+if (!delay_list.is_empty ())
-				    delay_list);
-if (delay_list)
 	unfilled_slots_base[i]
 	  = emit_delay_sequence (insn, delay_list, slots_filled);
 if (slots_to_fill == slots_filled)
 	unfilled_slots_base[i] = 0;
 note_delay_statistics (slots_filled, 0);
 }
-#ifdef DELAY_SLOTS_FOR_EPILOGUE
-/* See if the epilogue needs any delay slots.  Try to fill them if so.
-The only thing we can do is scan backwards from the end of the
-function.  If we did this in a previous pass, it is incorrect to do it
-again.  */
-if (crtl->epilogue_delay_list)
-return;
-slots_to_fill = DELAY_SLOTS_FOR_EPILOGUE;
-if (slots_to_fill == 0)
-return;
-slots_filled = 0;
-CLEAR_RESOURCE (&set);
-/* The frame pointer and stack pointer are needed at the beginning of
-the epilogue, so instructions setting them can not be put in the
-epilogue delay slot.  However, everything else needed at function
-end is safe, so we don't want to use end_of_function_needs here.  */
-CLEAR_RESOURCE (&needed);
-if (frame_pointer_needed)
-{
-SET_HARD_REG_BIT (needed.regs, FRAME_POINTER_REGNUM);
-#if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
-SET_HARD_REG_BIT (needed.regs, HARD_FRAME_POINTER_REGNUM);
-#endif
-if (! EXIT_IGNORE_STACK
-	  || current_function_sp_is_unchanging)
-	SET_HARD_REG_BIT (needed.regs, STACK_POINTER_REGNUM);
-}
-else
-SET_HARD_REG_BIT (needed.regs, STACK_POINTER_REGNUM);
-#ifdef EPILOGUE_USES
-for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
-{
-if (EPILOGUE_USES (i))
-	SET_HARD_REG_BIT (needed.regs, i);
-}
-#endif
-for (trial = get_last_insn (); ! stop_search_p (trial, 1);
-trial = PREV_INSN (trial))
-{
-if (NOTE_P (trial))
-	continue;
-pat = PATTERN (trial);
-if (GET_CODE (pat) == USE || GET_CODE (pat) == CLOBBER)
-	continue;
-if (! insn_references_resource_p (trial, &set, true)
-	  && ! insn_sets_resource_p (trial, &needed, true)
-	  && ! insn_sets_resource_p (trial, &set, true)
-#ifdef HAVE_cc0
-	  /* Don't want to mess with cc0 here.  */
-	  && ! reg_mentioned_p (cc0_rtx, pat)
-#endif
-	  && ! can_throw_internal (trial))
-	{
-	  trial = try_split (pat, trial, 1);
-	  if (ELIGIBLE_FOR_EPILOGUE_DELAY (trial, slots_filled))
-	    {
-	      /* Here as well we are searching backward, so put the
-		 insns we find on the head of the list.  */
-	      crtl->epilogue_delay_list
-		= gen_rtx_INSN_LIST (VOIDmode, trial,
-				     crtl->epilogue_delay_list);
-	      mark_end_of_function_resources (trial, true);
-	      update_block (trial, trial);
-	      delete_related_insns (trial);
-	      /* Clear deleted bit so final.c will output the insn.  */
-	      INSN_DELETED_P (trial) = 0;
-	      if (slots_to_fill == ++slots_filled)
-		break;
-	      continue;
-	    }
-	}
-mark_set_resources (trial, &set, 0, MARK_SRC_DEST_CALL);
-mark_referenced_resources (trial, &needed, true);
-}
-note_delay_statistics (slots_filled, 0);
-#endif
 }
-/* Follow any unconditional jump at LABEL;
+/* Follow any unconditional jump at LABEL, for the purpose of redirecting JUMP;
 return the ultimate label reached by any such chain of jumps.
-Return null if the chain ultimately leads to a return instruction.
+Return a suitable return rtx if the chain ultimately leads to a
+return instruction.
 If LABEL is not followed by a jump, return LABEL.
 If the chain loops or we can't find end, return LABEL,
-since that tells caller to avoid changing the insn.  */
+since that tells caller to avoid changing the insn.
+If the returned label is obtained by following a crossing jump,
+set *CROSSING to true, otherwise set it to false.  */
 static rtx
-follow_jumps (rtx label)
+follow_jumps (rtx label, rtx_insn *jump, bool *crossing)
 {
-rtx insn;
+rtx_insn *insn;
-rtx next;
+rtx_insn *next;
-rtx value = label;
 int depth;
+*crossing = false;
+if (ANY_RETURN_P (label))
+return label;
+rtx_insn *value = as_a <rtx_insn *> (label);
 for (depth = 0;
 (depth < 10
 	&& (insn = next_active_insn (value)) != 0
 	&& JUMP_P (insn)
-	&& ((JUMP_LABEL (insn) != 0 && any_uncondjump_p (insn)
+	&& JUMP_LABEL (insn) != NULL_RTX
-	     && onlyjump_p (insn))
+	&& ((any_uncondjump_p (insn) && onlyjump_p (insn))
-	    || GET_CODE (PATTERN (insn)) == RETURN)
+	    || ANY_RETURN_P (PATTERN (insn)))
 	&& (next = NEXT_INSN (insn))
 	&& BARRIER_P (next));
 depth++)
 {
-rtx tem;
+rtx this_label_or_return = JUMP_LABEL (insn);
 /* If we have found a cycle, make the insn jump to itself.  */
-if (JUMP_LABEL (insn) == label)
+if (this_label_or_return == label)
 	return label;
-tem = next_active_insn (JUMP_LABEL (insn));
+/* Cannot follow returns and cannot look through tablejumps.  */
-if (tem && (GET_CODE (PATTERN (tem)) == ADDR_VEC
+if (ANY_RETURN_P (this_label_or_return))
-		  || GET_CODE (PATTERN (tem)) == ADDR_DIFF_VEC))
+	return this_label_or_return;
+rtx_insn *this_label = as_a <rtx_insn *> (this_label_or_return);
+if (NEXT_INSN (this_label)
+	  && JUMP_TABLE_DATA_P (NEXT_INSN (this_label)))
 	break;
-value = JUMP_LABEL (insn);
+if (!targetm.can_follow_jump (jump, insn))
+	break;
+if (!*crossing)
+	*crossing = CROSSING_JUMP_P (jump);
+value = this_label;
 }
 if (depth == 10)
 return label;
 return value;
 }
 If OWN_THREAD is false, it must be the "true" thread of a jump.  In that
 case, we can only take insns from the head of the thread for our delay
 slot.  We then adjust the jump to point after the insns we have taken.  */
-static rtx
+static void
-fill_slots_from_thread (rtx insn, rtx condition, rtx thread,
+fill_slots_from_thread (rtx_jump_insn *insn, rtx condition,
-			rtx opposite_thread, int likely, int thread_if_true,
+			rtx thread_or_return, rtx opposite_thread, int likely,
-			int own_thread, int slots_to_fill,
+			int thread_if_true, int own_thread, int slots_to_fill,
-			int *pslots_filled, rtx delay_list)
+			int *pslots_filled, vec<rtx_insn *> *delay_list)
 {
 rtx new_thread;
 struct resources opposite_needed, set, needed;
-rtx trial;
+rtx_insn *trial;
 int lose = 0;
 int must_annul = 0;
 int flags;
 /* Validate our arguments.  */
-gcc_assert(condition != const_true_rtx || thread_if_true);
+gcc_assert (condition != const_true_rtx || thread_if_true);
-gcc_assert(own_thread || thread_if_true);
+gcc_assert (own_thread || thread_if_true);
 flags = get_jump_flags (insn, JUMP_LABEL (insn));
 /* If our thread is the end of subroutine, we can't get any delay
 insns from that.  */
-if (thread == 0)
+if (thread_or_return == NULL_RTX || ANY_RETURN_P (thread_or_return))
-return delay_list;
+return;
+rtx_insn *thread = as_a <rtx_insn *> (thread_or_return);
 /* If this is an unconditional branch, nothing is needed at the
 opposite thread.  Otherwise, compute what is needed there.  */
 if (condition == const_true_rtx)
 CLEAR_RESOURCE (&opposite_needed);
 /* If TRIAL conflicts with the insns ahead of it, we lose.  Also,
 	 don't separate or copy insns that set and use CC0.  */
 if (! insn_references_resource_p (trial, &set, true)
 	  && ! insn_sets_resource_p (trial, &set, true)
 	  && ! insn_sets_resource_p (trial, &needed, true)
-#ifdef HAVE_cc0
+	  && (!HAVE_cc0 || (! (reg_mentioned_p (cc0_rtx, pat)
-	  && ! (reg_mentioned_p (cc0_rtx, pat)
+			      && (! own_thread || ! sets_cc0_p (pat)))))
-		&& (! own_thread || ! sets_cc0_p (pat)))
-#endif
 	  && ! can_throw_internal (trial))
 	{
-	  rtx prior_insn;
+	  rtx_insn *prior_insn;
 	  /* If TRIAL is redundant with some insn before INSN, we don't
 	     actually need to add it to the delay list; we can merely pretend
 	     we did.  */
-	  if ((prior_insn = redundant_insn (trial, insn, delay_list)))
+	  if ((prior_insn = redundant_insn (trial, insn, *delay_list)))
 	    {
 	      fix_reg_dead_note (prior_insn, insn);
 	      if (own_thread)
 		{
 		  update_block (trial, thread);
 	      continue;
 	    }
 	  /* There are two ways we can win:  If TRIAL doesn't set anything
 	     needed at the opposite thread and can't trap, or if it can
-	     go into an annulled delay slot.  */
+	     go into an annulled delay slot.  But we want neither to copy
+	     nor to speculate frame-related insns.  */
 	  if (!must_annul
-	      && (condition == const_true_rtx
+	      && ((condition == const_true_rtx
+		   && (own_thread || !RTX_FRAME_RELATED_P (trial)))
 	          || (! insn_sets_resource_p (trial, &opposite_needed, true)
-		      && ! may_trap_or_fault_p (pat))))
+		      && ! may_trap_or_fault_p (pat)
+		      && ! RTX_FRAME_RELATED_P (trial))))
 	    {
 	      old_trial = trial;
 	      trial = try_split (pat, trial, 0);
 	      if (new_thread == old_trial)
 		new_thread = trial;
 		thread = trial;
 	      pat = PATTERN (trial);
 	      if (eligible_for_delay (insn, *pslots_filled, trial, flags))
 		goto winner;
 	    }
-	  else if (0
+	  else if (!RTX_FRAME_RELATED_P (trial)
-#ifdef ANNUL_IFTRUE_SLOTS
+		   && ((ANNUL_IFTRUE_SLOTS && ! thread_if_true)
-		   || ! thread_if_true
+		        || (ANNUL_IFFALSE_SLOTS && thread_if_true)))
-#endif
-#ifdef ANNUL_IFFALSE_SLOTS
-		   || thread_if_true
-#endif
-		   )
 	    {
 	      old_trial = trial;
 	      trial = try_split (pat, trial, 0);
 	      if (new_thread == old_trial)
 		new_thread = trial;
 	      if (thread == old_trial)
 		thread = trial;
 	      pat = PATTERN (trial);
-	      if ((must_annul || delay_list == NULL) && (thread_if_true
+	      if ((must_annul || delay_list->is_empty ()) && (thread_if_true
-		   ? check_annul_list_true_false (0, delay_list)
+		   ? check_annul_list_true_false (0, *delay_list)
 		     && eligible_for_annul_false (insn, *pslots_filled, trial, flags)
-		   : check_annul_list_true_false (1, delay_list)
+		   : check_annul_list_true_false (1, *delay_list)
 		     && eligible_for_annul_true (insn, *pslots_filled, trial, flags)))
 		{
-		  rtx temp;
+		  rtx_insn *temp;
 		  must_annul = 1;
 		winner:
-#ifdef HAVE_cc0
+		  if (HAVE_cc0 && reg_mentioned_p (cc0_rtx, pat))
-		  if (reg_mentioned_p (cc0_rtx, pat))
 		    link_cc0_insns (trial);
-#endif
 		  /* If we own this thread, delete the insn.  If this is the
 		     destination of a branch, show that a basic block status
 		     may have been updated.  In any case, mark the new
 		     starting point of this thread.  */
 			      LABEL_NUSES (XEXP (note, 0))++;
 			    else
 			      gcc_assert (REG_NOTE_KIND (note)
 					  == REG_LABEL_OPERAND);
 			  }
-		      if (JUMP_P (trial) && JUMP_LABEL (trial))
+		      if (jump_to_label_p (trial))
 			LABEL_NUSES (JUMP_LABEL (trial))++;
 		      delete_related_insns (trial);
 		      for (note = REG_NOTES (trial);
 			      LABEL_NUSES (XEXP (note, 0))--;
 			    else
 			      gcc_assert (REG_NOTE_KIND (note)
 					  == REG_LABEL_OPERAND);
 			  }
-		      if (JUMP_P (trial) && JUMP_LABEL (trial))
+		      if (jump_to_label_p (trial))
 			LABEL_NUSES (JUMP_LABEL (trial))--;
 		    }
 		  else
 		    new_thread = next_active_insn (trial);
-		  temp = own_thread ? trial : copy_rtx (trial);
+		  temp = own_thread ? trial : copy_delay_slot_insn (trial);
 		  if (thread_if_true)
 		    INSN_FROM_TARGET_P (temp) = 1;
-		  delay_list = add_to_delay_list (temp, delay_list);
+		  add_to_delay_list (temp, delay_list);
 		  if (slots_to_fill == ++(*pslots_filled))
 		    {
 		      /* Even though we have filled all the slots, we
 			 may be branching to a location that has a
 							true)
 			     && ! insn_references_resource_p (new_thread,
 							      &set, true)
 			     && (prior_insn
 				 = redundant_insn (new_thread, insn,
-						   delay_list)))
+						   *delay_list)))
 			{
 			  /* We know we do not own the thread, so no need
 			     to call update_block and delete_insn.  */
 			  fix_reg_dead_note (prior_insn, insn);
 			  update_reg_unused_notes (prior_insn, new_thread);
-			  new_thread = next_active_insn (new_thread);
+			  new_thread
+			    = next_active_insn (as_a<rtx_insn *> (new_thread));
 			}
 		      break;
 		    }
 		  continue;
 if (NONJUMP_INSN_P (trial) && GET_CODE (pat) == SET
 	  && REG_P (SET_SRC (pat))
 	  && REG_P (SET_DEST (pat))
 	  && !reg_overlap_mentioned_p (SET_DEST (pat), SET_SRC (pat)))
 	{
-	  rtx next = next_nonnote_insn (trial);
+	  rtx_insn *next = next_nonnote_insn (trial);
 	  if (next && NONJUMP_INSN_P (next)
 	      && GET_CODE (PATTERN (next)) != USE
 	      && ! reg_set_p (SET_DEST (pat), next)
 	      && ! reg_set_p (SET_SRC (pat), next)
 steal some of the insns in those slots.  */
 if (trial && NONJUMP_INSN_P (trial)
 && GET_CODE (PATTERN (trial)) == SEQUENCE
 && JUMP_P (XVECEXP (PATTERN (trial), 0, 0)))
 {
+rtx_sequence *sequence = as_a <rtx_sequence *> (PATTERN (trial));
 /* If this is the `true' thread, we will want to follow the jump,
 	 so we can only do this if we have taken everything up to here.  */
 if (thread_if_true && trial == new_thread)
 	{
-	  delay_list
+	  steal_delay_list_from_target (insn, condition, sequence,
-	    = steal_delay_list_from_target (insn, condition, PATTERN (trial),
+					delay_list, &set, &needed,
-					    delay_list, &set, &needed,
+					&opposite_needed, slots_to_fill,
-					    &opposite_needed, slots_to_fill,
+					pslots_filled, &must_annul,
-					    pslots_filled, &must_annul,
+					&new_thread);
-					    &new_thread);
 	  /* If we owned the thread and are told that it branched
 	     elsewhere, make sure we own the thread at the new location.  */
 	  if (own_thread && trial != new_thread)
 	    own_thread = own_thread_p (new_thread, new_thread, 0);
 	}
 else if (! thread_if_true)
-	delay_list
+	steal_delay_list_from_fallthrough (insn, condition, sequence,
-	  = steal_delay_list_from_fallthrough (insn, condition,
+					   delay_list, &set, &needed,
-					       PATTERN (trial),
+					   &opposite_needed, slots_to_fill,
-					       delay_list, &set, &needed,
+					   pslots_filled, &must_annul);
-					       &opposite_needed, slots_to_fill,
-					       pslots_filled, &must_annul);
 }
 /* If we haven't found anything for this delay slot and it is very
 likely that the branch will be taken, see if the insn at our target
 increments or decrements a register with an increment that does not
 depend on the destination register.  If so, try to place the opposite
 arithmetic insn after the jump insn and put the arithmetic insn in the
 delay slot.  If we can't do this, return.  */
-if (delay_list == 0 && likely && new_thread
+if (delay_list->is_empty () && likely
+&& new_thread && !ANY_RETURN_P (new_thread)
 && NONJUMP_INSN_P (new_thread)
+&& !RTX_FRAME_RELATED_P (new_thread)
 && GET_CODE (PATTERN (new_thread)) != ASM_INPUT
 && asm_noperands (PATTERN (new_thread)) < 0)
 {
 rtx pat = PATTERN (new_thread);
 rtx dest;
 rtx src;
-trial = new_thread;
+/* We know "new_thread" is an insn due to NONJUMP_INSN_P (new_thread)
+	 above.  */
+trial = as_a <rtx_insn *> (new_thread);
 pat = PATTERN (trial);
 if (!NONJUMP_INSN_P (trial)
 	  || GET_CODE (pat) != SET
 	  || ! eligible_for_delay (insn, 0, trial, flags)
 	  || can_throw_internal (trial))
-	return 0;
+	return;
 dest = SET_DEST (pat), src = SET_SRC (pat);
 if ((GET_CODE (src) == PLUS || GET_CODE (src) == MINUS)
 	  && rtx_equal_p (XEXP (src, 0), dest)
 	  && (!FLOAT_MODE_P (GET_MODE (src))
 	  && ! reg_overlap_mentioned_p (dest, XEXP (src, 1))
 	  && ! side_effects_p (pat))
 	{
 	  rtx other = XEXP (src, 1);
 	  rtx new_arith;
-	  rtx ninsn;
+	  rtx_insn *ninsn;
 	  /* If this is a constant adjustment, use the same code with
 	     the negated constant.  Otherwise, reverse the sense of the
 	     arithmetic.  */
 	  if (CONST_INT_P (other))
 					negate_rtx (GET_MODE (src), other));
 	  else
 	    new_arith = gen_rtx_fmt_ee (GET_CODE (src) == PLUS ? MINUS : PLUS,
 					GET_MODE (src), dest, other);
-	  ninsn = emit_insn_after (gen_rtx_SET (VOIDmode, dest, new_arith),
+	  ninsn = emit_insn_after (gen_rtx_SET (dest, new_arith), insn);
-				   insn);
 	  if (recog_memoized (ninsn) < 0
-	      || (extract_insn (ninsn), ! constrain_operands (1)))
+	      || (extract_insn (ninsn),
+		  !constrain_operands (1, get_preferred_alternatives (ninsn))))
 	    {
 	      delete_related_insns (ninsn);
-	      return 0;
+	      return;
 	    }
 	  if (own_thread)
 	    {
 	      update_block (trial, thread);
 	      delete_related_insns (trial);
 	    }
 	  else
 	    new_thread = next_active_insn (trial);
-	  ninsn = own_thread ? trial : copy_rtx (trial);
+	  ninsn = own_thread ? trial : copy_delay_slot_insn (trial);
 	  if (thread_if_true)
 	    INSN_FROM_TARGET_P (ninsn) = 1;
-	  delay_list = add_to_delay_list (ninsn, NULL_RTX);
+	  add_to_delay_list (ninsn, delay_list);
 	  (*pslots_filled)++;
 	}
 }
-if (delay_list && must_annul)
+if (!delay_list->is_empty () && must_annul)
 INSN_ANNULLED_BRANCH_P (insn) = 1;
 /* If we are to branch into the middle of this thread, find an appropriate
 label or make a new one if none, and redirect INSN to it.  If we hit the
 end of the function, use the end-of-function label.  */
 if (new_thread != thread)
 {
 rtx label;
+bool crossing = false;
 gcc_assert (thread_if_true);
-if (new_thread && JUMP_P (new_thread)
+if (new_thread && simplejump_or_return_p (new_thread)
-	  && (simplejump_p (new_thread)
-	      || GET_CODE (PATTERN (new_thread)) == RETURN)
 	  && redirect_with_delay_list_safe_p (insn,
 					      JUMP_LABEL (new_thread),
-					      delay_list))
+					      *delay_list))
-	new_thread = follow_jumps (JUMP_LABEL (new_thread));
+	new_thread = follow_jumps (JUMP_LABEL (new_thread), insn,
+				   &crossing);
-if (new_thread == 0)
-	label = find_end_label ();
+if (ANY_RETURN_P (new_thread))
+	label = find_end_label (new_thread);
 else if (LABEL_P (new_thread))
 	label = new_thread;
 else
-	label = get_label_before (new_thread);
+	label = get_label_before (as_a <rtx_insn *> (new_thread),
+				  JUMP_LABEL (insn));
 if (label)
-	reorg_redirect_jump (insn, label);
+	{
-}
+	  reorg_redirect_jump (insn, label);
+	  if (crossing)
-return delay_list;
+	    CROSSING_JUMP_P (insn) = 1;
+	}
+}
 }
 /* Make another attempt to find insns to place in delay slots.
 We previously looked for insns located in front of the delay insn
 if safe.  */
 static void
 fill_eager_delay_slots (void)
 {
-rtx insn;
+rtx_insn *insn;
 int i;
 int num_unfilled_slots = unfilled_slots_next - unfilled_slots_base;
 for (i = 0; i < num_unfilled_slots; i++)
 {
 rtx condition;
-rtx target_label, insn_at_target, fallthrough_insn;
+rtx target_label, insn_at_target;
-rtx delay_list = 0;
+rtx_insn *fallthrough_insn;
+auto_vec<rtx_insn *, 5> delay_list;
+rtx_jump_insn *jump_insn;
 int own_target;
 int own_fallthrough;
 int prediction, slots_to_fill, slots_filled;
 insn = unfilled_slots_base[i];
 if (insn == 0
-	  || INSN_DELETED_P (insn)
+	  || insn->deleted ()
-	  || !JUMP_P (insn)
+	  || ! (jump_insn = dyn_cast <rtx_jump_insn *> (insn))
-	  || ! (condjump_p (insn) || condjump_in_parallel_p (insn)))
+	  || ! (condjump_p (jump_insn) || condjump_in_parallel_p (jump_insn)))
 	continue;
-slots_to_fill = num_delay_slots (insn);
+slots_to_fill = num_delay_slots (jump_insn);
 /* Some machine description have defined instructions to have
 	 delay slots only in certain circumstances which may depend on
 	 nearby insns (which change due to reorg's actions).
 	 For example, the PA port normally has delay slots for unconditional
 	 the unconditional jump.  */
 if (slots_to_fill == 0)
 	continue;
 slots_filled = 0;
-target_label = JUMP_LABEL (insn);
+target_label = JUMP_LABEL (jump_insn);
-condition = get_branch_condition (insn, target_label);
+condition = get_branch_condition (jump_insn, target_label);
 if (condition == 0)
 	continue;
 /* Get the next active fallthrough and target insns and see if we own
 	 them.  Then see whether the branch is likely true.  We don't need
 	 to do a lot of this for unconditional branches.  */
-insn_at_target = next_active_insn (target_label);
+insn_at_target = first_active_target_insn (target_label);
 own_target = own_thread_p (target_label, target_label, 0);
 if (condition == const_true_rtx)
 	{
 	  own_fallthrough = 0;
 	  fallthrough_insn = 0;
 	  prediction = 2;
 	}
 else
 	{
-	  fallthrough_insn = next_active_insn (insn);
+	  fallthrough_insn = next_active_insn (jump_insn);
-	  own_fallthrough = own_thread_p (NEXT_INSN (insn), NULL_RTX, 1);
+	  own_fallthrough = own_thread_p (NEXT_INSN (jump_insn), NULL_RTX, 1);
-	  prediction = mostly_true_jump (insn, condition);
+	  prediction = mostly_true_jump (jump_insn);
 	}
 /* If this insn is expected to branch, first try to get insns from our
 	 target, then our fallthrough insns.  If it is not expected to branch,
 	 try the other order.  */
 if (prediction > 0)
 	{
-	  delay_list
+	  fill_slots_from_thread (jump_insn, condition, insn_at_target,
-	    = fill_slots_from_thread (insn, condition, insn_at_target,
+				  fallthrough_insn, prediction == 2, 1,
-				      fallthrough_insn, prediction == 2, 1,
+				  own_target,
-				      own_target,
+				  slots_to_fill, &slots_filled, &delay_list);
-				      slots_to_fill, &slots_filled, delay_list);
+	  if (delay_list.is_empty () && own_fallthrough)
-	  if (delay_list == 0 && own_fallthrough)
 	    {
 	      /* Even though we didn't find anything for delay slots,
 		 we might have found a redundant insn which we deleted
 		 from the thread that was filled.  So we have to recompute
 		 the next insn at the target.  */
-	      target_label = JUMP_LABEL (insn);
+	      target_label = JUMP_LABEL (jump_insn);
-	      insn_at_target = next_active_insn (target_label);
+	      insn_at_target = first_active_target_insn (target_label);
-	      delay_list
+	      fill_slots_from_thread (jump_insn, condition, fallthrough_insn,
-		= fill_slots_from_thread (insn, condition, fallthrough_insn,
+				      insn_at_target, 0, 0, own_fallthrough,
-					  insn_at_target, 0, 0,
+				      slots_to_fill, &slots_filled,
-					  own_fallthrough,
+				      &delay_list);
-					  slots_to_fill, &slots_filled,
-					  delay_list);
 	    }
 	}
 else
 	{
 	  if (own_fallthrough)
-	    delay_list
+	    fill_slots_from_thread (jump_insn, condition, fallthrough_insn,
-	      = fill_slots_from_thread (insn, condition, fallthrough_insn,
+				    insn_at_target, 0, 0, own_fallthrough,
-					insn_at_target, 0, 0,
+				    slots_to_fill, &slots_filled, &delay_list);
-					own_fallthrough,
-					slots_to_fill, &slots_filled,
+	  if (delay_list.is_empty ())
-					delay_list);
+	    fill_slots_from_thread (jump_insn, condition, insn_at_target,
+				    next_active_insn (insn), 0, 1, own_target,
-	  if (delay_list == 0)
+				    slots_to_fill, &slots_filled, &delay_list);
-	    delay_list
+	}
-	      = fill_slots_from_thread (insn, condition, insn_at_target,
-					next_active_insn (insn), 0, 1,
+if (!delay_list.is_empty ())
-					own_target,
-					slots_to_fill, &slots_filled,
-					delay_list);
-	}
-if (delay_list)
 	unfilled_slots_base[i]
-	  = emit_delay_sequence (insn, delay_list, slots_filled);
+	  = emit_delay_sequence (jump_insn, delay_list, slots_filled);
 if (slots_to_fill == slots_filled)
 	unfilled_slots_base[i] = 0;
 note_delay_statistics (slots_filled, 1);
 }
 }
-static void delete_computation (rtx insn);
+static void delete_computation (rtx_insn *insn);
 /* Recursively delete prior insns that compute the value (used only by INSN
 which the caller is deleting) stored in the register mentioned by NOTE
 which is a REG_DEAD note associated with INSN.  */
 static void
-delete_prior_computation (rtx note, rtx insn)
+delete_prior_computation (rtx note, rtx_insn *insn)
 {
-rtx our_prev;
+rtx_insn *our_prev;
 rtx reg = XEXP (note, 0);
 for (our_prev = prev_nonnote_insn (insn);
 our_prev && (NONJUMP_INSN_P (our_prev)
 		    || CALL_P (our_prev));
 On machines with CC0, if CC0 is used in this insn, we may be able to
 delete the insn that set it.  */
 static void
-delete_computation (rtx insn)
+delete_computation (rtx_insn *insn)
 {
 rtx note, next;
-#ifdef HAVE_cc0
+if (HAVE_cc0 && reg_referenced_p (cc0_rtx, PATTERN (insn)))
-if (reg_referenced_p (cc0_rtx, PATTERN (insn)))
+{
-{
+rtx_insn *prev = prev_nonnote_insn (insn);
-rtx prev = prev_nonnote_insn (insn);
 /* We assume that at this stage
 	 CC's are always set explicitly
 	 and always immediately before the jump that
 	 will use them.  So if the previous insn
 	 exists to set the CC's, delete it
 	  else
 	    /* Otherwise, show that cc0 won't be used.  */
 	    add_reg_note (prev, REG_UNUSED, cc0_rtx);
 	}
 }
-#endif
 for (note = REG_NOTES (insn); note; note = next)
 {
 next = XEXP (note, 1);
 /* If all INSN does is set the pc, delete it,
 and delete the insn that set the condition codes for it
 if that's what the previous thing was.  */
 static void
-delete_jump (rtx insn)
+delete_jump (rtx_insn *insn)
 {
 rtx set = single_set (insn);
 if (set && GET_CODE (SET_DEST (set)) == PC)
 delete_computation (insn);
+}
+static rtx_insn *
+label_before_next_insn (rtx_insn *x, rtx scan_limit)
+{
+rtx_insn *insn = next_active_insn (x);
+while (insn)
+{
+insn = PREV_INSN (insn);
+if (insn == scan_limit || insn == NULL_RTX)
+	return NULL;
+if (LABEL_P (insn))
+	break;
+}
+return insn;
+}
+/* Return TRUE if there is a NOTE_INSN_SWITCH_TEXT_SECTIONS note in between
+BEG and END.  */
+static bool
+switch_text_sections_between_p (const rtx_insn *beg, const rtx_insn *end)
+{
+const rtx_insn *p;
+for (p = beg; p != end; p = NEXT_INSN (p))
+if (NOTE_P (p) && NOTE_KIND (p) == NOTE_INSN_SWITCH_TEXT_SECTIONS)
+return true;
+return false;
 }
 /* Once we have tried two ways to fill a delay slot, make a pass over the
 code to try to improve the results and to do such things as more jump
 threading.  */
 static void
-relax_delay_slots (rtx first)
+relax_delay_slots (rtx_insn *first)
 {
-rtx insn, next, pat;
+rtx_insn *insn, *next;
-rtx trial, delay_insn, target_label;
+rtx_sequence *pat;
+rtx_insn *delay_insn;
+rtx target_label;
 /* Look at every JUMP_INSN and see if we can improve it.  */
 for (insn = first; insn; insn = next)
 {
-rtx other;
+rtx_insn *other;
+bool crossing;
 next = next_active_insn (insn);
 /* If this is a jump insn, see if it now jumps to a jump, jumps to
 	 the next insn, or jumps to a label that is not the last of a
 	 group of consecutive labels.  */
-if (JUMP_P (insn)
+if (is_a <rtx_jump_insn *> (insn)
 	  && (condjump_p (insn) || condjump_in_parallel_p (insn))
-	  && (target_label = JUMP_LABEL (insn)) != 0)
+	  && !ANY_RETURN_P (target_label = JUMP_LABEL (insn)))
 	{
-	  target_label = skip_consecutive_labels (follow_jumps (target_label));
+	  rtx_jump_insn *jump_insn = as_a <rtx_jump_insn *> (insn);
-	  if (target_label == 0)
+	  target_label
-	    target_label = find_end_label ();
+	    = skip_consecutive_labels (follow_jumps (target_label, jump_insn,
+						     &crossing));
-	  if (target_label && next_active_insn (target_label) == next
+	  if (ANY_RETURN_P (target_label))
-	      && ! condjump_in_parallel_p (insn))
+	    target_label = find_end_label (target_label);
+	  if (target_label
+	      && next_active_insn (as_a<rtx_insn *> (target_label)) == next
+	      && ! condjump_in_parallel_p (jump_insn)
+	      && ! (next && switch_text_sections_between_p (jump_insn, next)))
 	    {
-	      delete_jump (insn);
+	      delete_jump (jump_insn);
 	      continue;
 	    }
-	  if (target_label && target_label != JUMP_LABEL (insn))
+	  if (target_label && target_label != JUMP_LABEL (jump_insn))
-	    reorg_redirect_jump (insn, target_label);
+	    {
+	      reorg_redirect_jump (jump_insn, target_label);
+	      if (crossing)
+		CROSSING_JUMP_P (jump_insn) = 1;
+	    }
 	  /* See if this jump conditionally branches around an unconditional
 	     jump.  If so, invert this jump and point it to the target of the
-	     second jump.  */
+	     second jump.  Check if it's possible on the target.  */
-	  if (next && JUMP_P (next)
+	  if (next && simplejump_or_return_p (next)
-	      && any_condjump_p (insn)
+	      && any_condjump_p (jump_insn)
-	      && (simplejump_p (next) || GET_CODE (PATTERN (next)) == RETURN)
 	      && target_label
-	      && next_active_insn (target_label) == next_active_insn (next)
+	      && (next_active_insn (as_a<rtx_insn *> (target_label))
-	      && no_labels_between_p (insn, next))
+		  == next_active_insn (next))
+	      && no_labels_between_p (jump_insn, next)
+	      && targetm.can_follow_jump (jump_insn, next))
 	    {
 	      rtx label = JUMP_LABEL (next);
 	      /* Be careful how we do this to avoid deleting code or
 		 labels that are momentarily dead.  See similar optimization
 		 We also need to ensure we properly handle the case when
 		 invert_jump fails.  */
 	      ++LABEL_NUSES (target_label);
-	      if (label)
+	      if (!ANY_RETURN_P (label))
 		++LABEL_NUSES (label);
-	      if (invert_jump (insn, label, 1))
+	      if (invert_jump (jump_insn, label, 1))
 		{
 		  delete_related_insns (next);
-		  next = insn;
+		  next = jump_insn;
 		}
-	      if (label)
+	      if (!ANY_RETURN_P (label))
 		--LABEL_NUSES (label);
 	      if (--LABEL_NUSES (target_label) == 0)
 		delete_related_insns (target_label);
 	 fill the slots.
 	 Don't do this if we expect the conditional branch to be true, because
 	 we would then be making the more common case longer.  */
-if (JUMP_P (insn)
+if (simplejump_or_return_p (insn)
-	  && (simplejump_p (insn) || GET_CODE (PATTERN (insn)) == RETURN)
 	  && (other = prev_active_insn (insn)) != 0
 	  && any_condjump_p (other)
 	  && no_labels_between_p (other, insn)
-	  && 0 > mostly_true_jump (other,
+	  && 0 > mostly_true_jump (other))
-				   get_branch_condition (other,
-							 JUMP_LABEL (other))))
 	{
 	  rtx other_target = JUMP_LABEL (other);
 	  target_label = JUMP_LABEL (insn);
-	  if (invert_jump (other, target_label, 0))
+	  if (invert_jump (as_a <rtx_jump_insn *> (other), target_label, 0))
-	    reorg_redirect_jump (insn, other_target);
+	    reorg_redirect_jump (as_a <rtx_jump_insn *> (insn), other_target);
 	}
-/* Now look only at cases where we have filled a delay slot.  */
+/* Now look only at cases where we have a filled delay slot.  */
-if (!NONJUMP_INSN_P (insn)
+if (!NONJUMP_INSN_P (insn) || GET_CODE (PATTERN (insn)) != SEQUENCE)
-	  || GET_CODE (PATTERN (insn)) != SEQUENCE)
 	continue;
-pat = PATTERN (insn);
+pat = as_a <rtx_sequence *> (PATTERN (insn));
-delay_insn = XVECEXP (pat, 0, 0);
+delay_insn = pat->insn (0);
 /* See if the first insn in the delay slot is redundant with some
 	 previous insn.  Remove it from the delay slot if so; then set up
 	 to reprocess this insn.  */
-if (redundant_insn (XVECEXP (pat, 0, 1), delay_insn, 0))
+if (redundant_insn (pat->insn (1), delay_insn, vNULL))
 	{
-	  delete_from_delay_slot (XVECEXP (pat, 0, 1));
+	  update_block (pat->insn (1), insn);
+	  delete_from_delay_slot (pat->insn (1));
 	  next = prev_active_insn (next);
 	  continue;
 	}
 /* See if we have a RETURN insn with a filled delay slot followed
 	 effect in fewer instructions.
 	 Only do so if optimizing for size since this results in slower, but
 	 smaller code.  */
 if (optimize_function_for_size_p (cfun)
-	  && GET_CODE (PATTERN (delay_insn)) == RETURN
+	  && ANY_RETURN_P (PATTERN (delay_insn))
 	  && next
 	  && JUMP_P (next)
-	  && GET_CODE (PATTERN (next)) == RETURN)
+	  && PATTERN (next) == PATTERN (delay_insn))
 	{
-	  rtx after;
+	  rtx_insn *after;
 	  int i;
 	  /* Delete the RETURN and just execute the delay list insns.
 	     We do this by deleting the INSN containing the SEQUENCE, then
 	     Clear the from target bit, since these insns are no longer
 	     in delay slots.  */
 	  for (i = 0; i < XVECLEN (pat, 0); i++)
 	    INSN_FROM_TARGET_P (XVECEXP (pat, 0, i)) = 0;
-	  trial = PREV_INSN (insn);
+	  rtx_insn *prev = PREV_INSN (insn);
 	  delete_related_insns (insn);
 	  gcc_assert (GET_CODE (pat) == SEQUENCE);
-	  add_insn_after (delay_insn, trial, NULL);
+	  add_insn_after (delay_insn, prev, NULL);
 	  after = delay_insn;
-	  for (i = 1; i < XVECLEN (pat, 0); i++)
+	  for (i = 1; i < pat->len (); i++)
-	    after = emit_copy_of_insn_after (XVECEXP (pat, 0, i), after);
+	    after = emit_copy_of_insn_after (pat->insn (i), after);
 	  delete_scheduled_jump (delay_insn);
 	  continue;
 	}
 /* Now look only at the cases where we have a filled JUMP_INSN.  */
-if (!JUMP_P (XVECEXP (PATTERN (insn), 0, 0))
+rtx_jump_insn *delay_jump_insn =
-	  || ! (condjump_p (XVECEXP (PATTERN (insn), 0, 0))
+		dyn_cast <rtx_jump_insn *> (delay_insn);
-		|| condjump_in_parallel_p (XVECEXP (PATTERN (insn), 0, 0))))
+if (! delay_jump_insn || !(condjump_p (delay_jump_insn)
+	  || condjump_in_parallel_p (delay_jump_insn)))
 	continue;
-target_label = JUMP_LABEL (delay_insn);
+target_label = JUMP_LABEL (delay_jump_insn);
+if (target_label && ANY_RETURN_P (target_label))
-if (target_label)
+	continue;
-	{
-	  /* If this jump goes to another unconditional jump, thread it, but
+/* If this jump goes to another unconditional jump, thread it, but
-	     don't convert a jump into a RETURN here.  */
+	 don't convert a jump into a RETURN here.  */
-	  trial = skip_consecutive_labels (follow_jumps (target_label));
+rtx trial = skip_consecutive_labels (follow_jumps (target_label,
-	  if (trial == 0)
+							 delay_jump_insn,
-	    trial = find_end_label ();
+							 &crossing));
+if (ANY_RETURN_P (trial))
-	  if (trial && trial != target_label
+	trial = find_end_label (trial);
-	      && redirect_with_delay_slots_safe_p (delay_insn, trial, insn))
+if (trial && trial != target_label
+	  && redirect_with_delay_slots_safe_p (delay_jump_insn, trial, insn))
+	{
+	  reorg_redirect_jump (delay_jump_insn, trial);
+	  target_label = trial;
+	  if (crossing)
+	    CROSSING_JUMP_P (delay_jump_insn) = 1;
+	}
+/* If the first insn at TARGET_LABEL is redundant with a previous
+	 insn, redirect the jump to the following insn and process again.
+	 We use next_real_insn instead of next_active_insn so we
+	 don't skip USE-markers, or we'll end up with incorrect
+	 liveness info.  */
+trial = next_real_insn (target_label);
+if (trial && GET_CODE (PATTERN (trial)) != SEQUENCE
+	  && redundant_insn (trial, insn, vNULL)
+	  && ! can_throw_internal (trial))
+	{
+	  /* Figure out where to emit the special USE insn so we don't
+	     later incorrectly compute register live/death info.  */
+	  rtx_insn *tmp = next_active_insn (as_a<rtx_insn *> (trial));
+	  if (tmp == 0)
+	    tmp = find_end_label (simple_return_rtx);
+	  if (tmp)
 	    {
-	      reorg_redirect_jump (delay_insn, trial);
+	      /* Insert the special USE insn and update dataflow info.
-	      target_label = trial;
+		 We know "trial" is an insn here as it is the output of
+		 next_real_insn () above.  */
+	      update_block (as_a <rtx_insn *> (trial), tmp);
+	      /* Now emit a label before the special USE insn, and
+		 redirect our jump to the new label.  */
+	      target_label = get_label_before (PREV_INSN (tmp), target_label);
+	      reorg_redirect_jump (delay_jump_insn, target_label);
+	      next = insn;
+	      continue;
 	    }
+	}
-	  /* If the first insn at TARGET_LABEL is redundant with a previous
-	     insn, redirect the jump to the following insn and process again.
+/* Similarly, if it is an unconditional jump with one insn in its
-	     We use next_real_insn instead of next_active_insn so we
+	 delay list and that insn is redundant, thread the jump.  */
-	     don't skip USE-markers, or we'll end up with incorrect
+rtx_sequence *trial_seq =
-	     liveness info.  */
+	trial ? dyn_cast <rtx_sequence *> (PATTERN (trial)) : NULL;
-	  trial = next_real_insn (target_label);
+if (trial_seq
-	  if (trial && GET_CODE (PATTERN (trial)) != SEQUENCE
+	  && trial_seq->len () == 2
-	      && redundant_insn (trial, insn, 0)
+	  && JUMP_P (trial_seq->insn (0))
-	      && ! can_throw_internal (trial))
+	  && simplejump_or_return_p (trial_seq->insn (0))
+	  && redundant_insn (trial_seq->insn (1), insn, vNULL))
+	{
+	  rtx temp_label = JUMP_LABEL (trial_seq->insn (0));
+	  if (ANY_RETURN_P (temp_label))
+	    temp_label = find_end_label (temp_label);
+	  if (temp_label
+	      && redirect_with_delay_slots_safe_p (delay_jump_insn,
+						   temp_label, insn))
 	    {
-	      /* Figure out where to emit the special USE insn so we don't
+	      update_block (trial_seq->insn (1), insn);
-		 later incorrectly compute register live/death info.  */
+	      reorg_redirect_jump (delay_jump_insn, temp_label);
-	      rtx tmp = next_active_insn (trial);
+	      next = insn;
-	      if (tmp == 0)
+	      continue;
-		tmp = find_end_label ();
-	      if (tmp)
-	        {
-		  /* Insert the special USE insn and update dataflow info.  */
-		  update_block (trial, tmp);
-		  /* Now emit a label before the special USE insn, and
-		     redirect our jump to the new label.  */
-		  target_label = get_label_before (PREV_INSN (tmp));
-		  reorg_redirect_jump (delay_insn, target_label);
-		  next = insn;
-		  continue;
-		}
 	    }
+	}
-	  /* Similarly, if it is an unconditional jump with one insn in its
-	     delay list and that insn is redundant, thread the jump.  */
+/* See if we have a simple (conditional) jump that is useless.  */
-	  if (trial && GET_CODE (PATTERN (trial)) == SEQUENCE
+if (! INSN_ANNULLED_BRANCH_P (delay_jump_insn)
-	      && XVECLEN (PATTERN (trial), 0) == 2
+	  && ! condjump_in_parallel_p (delay_jump_insn)
-	      && JUMP_P (XVECEXP (PATTERN (trial), 0, 0))
+	  && prev_active_insn (as_a<rtx_insn *> (target_label)) == insn
-	      && (simplejump_p (XVECEXP (PATTERN (trial), 0, 0))
+	  && ! BARRIER_P (prev_nonnote_insn (as_a<rtx_insn *> (target_label)))
-		  || GET_CODE (PATTERN (XVECEXP (PATTERN (trial), 0, 0))) == RETURN)
-	      && redundant_insn (XVECEXP (PATTERN (trial), 0, 1), insn, 0))
-	    {
-	      target_label = JUMP_LABEL (XVECEXP (PATTERN (trial), 0, 0));
-	      if (target_label == 0)
-		target_label = find_end_label ();
-	      if (target_label
-	          && redirect_with_delay_slots_safe_p (delay_insn, target_label,
-						       insn))
-		{
-		  reorg_redirect_jump (delay_insn, target_label);
-		  next = insn;
-		  continue;
-		}
-	    }
-	}
-if (! INSN_ANNULLED_BRANCH_P (delay_insn)
-	  && prev_active_insn (target_label) == insn
-	  && ! condjump_in_parallel_p (delay_insn)
-#ifdef HAVE_cc0
 	  /* If the last insn in the delay slot sets CC0 for some insn,
 	     various code assumes that it is in a delay slot.  We could
 	     put it back where it belonged and delete the register notes,
 	     but it doesn't seem worthwhile in this uncommon case.  */
-	  && ! find_reg_note (XVECEXP (pat, 0, XVECLEN (pat, 0) - 1),
+	  && (!HAVE_cc0
-			      REG_CC_USER, NULL_RTX)
+	      || ! find_reg_note (XVECEXP (pat, 0, XVECLEN (pat, 0) - 1),
-#endif
+				  REG_CC_USER, NULL_RTX)))
-	  )
+	{
-	{
+	  rtx_insn *after;
-	  rtx after;
 	  int i;
 	  /* All this insn does is execute its delay list and jump to the
 	     following insn.  So delete the jump and just execute the delay
 	     list insns.
 	     Clear the from target bit, since these insns are no longer
 	     in delay slots.  */
 	  for (i = 0; i < XVECLEN (pat, 0); i++)
 	    INSN_FROM_TARGET_P (XVECEXP (pat, 0, i)) = 0;
-	  trial = PREV_INSN (insn);
+	  rtx_insn *prev = PREV_INSN (insn);
 	  delete_related_insns (insn);
 	  gcc_assert (GET_CODE (pat) == SEQUENCE);
-	  add_insn_after (delay_insn, trial, NULL);
+	  add_insn_after (delay_jump_insn, prev, NULL);
-	  after = delay_insn;
+	  after = delay_jump_insn;
-	  for (i = 1; i < XVECLEN (pat, 0); i++)
+	  for (i = 1; i < pat->len (); i++)
-	    after = emit_copy_of_insn_after (XVECEXP (pat, 0, i), after);
+	    after = emit_copy_of_insn_after (pat->insn (i), after);
-	  delete_scheduled_jump (delay_insn);
+	  delete_scheduled_jump (delay_jump_insn);
 	  continue;
 	}
 /* See if this is an unconditional jump around a single insn which is
 	 identical to the one in its delay slot.  In this case, we can just
 	 delete the branch and the insn in its delay slot.  */
 if (next && NONJUMP_INSN_P (next)
-	  && prev_label (next_active_insn (next)) == target_label
+	  && label_before_next_insn (next, insn) == target_label
 	  && simplejump_p (insn)
 	  && XVECLEN (pat, 0) == 2
-	  && rtx_equal_p (PATTERN (next), PATTERN (XVECEXP (pat, 0, 1))))
+	  && rtx_equal_p (PATTERN (next), PATTERN (pat->insn (1))))
 	{
 	  delete_related_insns (insn);
 	  continue;
 	}
 /* See if this jump (with its delay slots) conditionally branches
 	 around an unconditional jump (without delay slots).  If so, invert
 	 this jump and point it to the target of the second jump.  We cannot
 	 do this for annulled jumps, though.  Again, don't convert a jump to
 	 a RETURN here.  */
-if (! INSN_ANNULLED_BRANCH_P (delay_insn)
+if (! INSN_ANNULLED_BRANCH_P (delay_jump_insn)
-	  && any_condjump_p (delay_insn)
+	  && any_condjump_p (delay_jump_insn)
-	  && next && JUMP_P (next)
+	  && next && simplejump_or_return_p (next)
-	  && (simplejump_p (next) || GET_CODE (PATTERN (next)) == RETURN)
+	  && (next_active_insn (as_a<rtx_insn *> (target_label))
-	  && next_active_insn (target_label) == next_active_insn (next)
+	      == next_active_insn (next))
 	  && no_labels_between_p (insn, next))
 	{
 	  rtx label = JUMP_LABEL (next);
-	  rtx old_label = JUMP_LABEL (delay_insn);
+	  rtx old_label = JUMP_LABEL (delay_jump_insn);
-	  if (label == 0)
+	  if (ANY_RETURN_P (label))
-	    label = find_end_label ();
+	    label = find_end_label (label);
 	  /* find_end_label can generate a new label. Check this first.  */
 	  if (label
 	      && no_labels_between_p (insn, next)
-	      && redirect_with_delay_slots_safe_p (delay_insn, label, insn))
+	      && redirect_with_delay_slots_safe_p (delay_jump_insn,
+						   label, insn))
 	    {
 	      /* Be careful how we do this to avoid deleting code or labels
 		 that are momentarily dead.  See similar optimization in
 		 jump.c  */
 	      if (old_label)
 		++LABEL_NUSES (old_label);
-	      if (invert_jump (delay_insn, label, 1))
+	      if (invert_jump (delay_jump_insn, label, 1))
 		{
 		  int i;
 		  /* Must update the INSN_FROM_TARGET_P bits now that
 		     the branch is reversed, so that mark_target_live_regs
 	    }
 	}
 /* If we own the thread opposite the way this insn branches, see if we
 	 can merge its delay slots with following insns.  */
-if (INSN_FROM_TARGET_P (XVECEXP (pat, 0, 1))
+if (INSN_FROM_TARGET_P (pat->insn (1))
 	  && own_thread_p (NEXT_INSN (insn), 0, 1))
 	try_merge_delay_insns (insn, next);
-else if (! INSN_FROM_TARGET_P (XVECEXP (pat, 0, 1))
+else if (! INSN_FROM_TARGET_P (pat->insn (1))
 	       && own_thread_p (target_label, target_label, 0))
-	try_merge_delay_insns (insn, next_active_insn (target_label));
+	try_merge_delay_insns (insn,
+			       next_active_insn (as_a<rtx_insn *> (target_label)));
 /* If we get here, we haven't deleted INSN.  But we may have deleted
 	 NEXT, so recompute it.  */
 next = next_active_insn (insn);
 }
 }
-#ifdef HAVE_return
 /* Look for filled jumps to the end of function label.  We can try to convert
 them into RETURN insns if the insns in the delay slot are valid for the
 RETURN as well.  */
 static void
-make_return_insns (rtx first)
+make_return_insns (rtx_insn *first)
 {
-rtx insn, jump_insn, pat;
+rtx_insn *insn;
-rtx real_return_label = end_of_function_label;
+rtx_jump_insn *jump_insn;
+rtx real_return_label = function_return_label;
+rtx real_simple_return_label = function_simple_return_label;
 int slots, i;
-#ifdef DELAY_SLOTS_FOR_EPILOGUE
-/* If a previous pass filled delay slots in the epilogue, things get a
-bit more complicated, as those filler insns would generally (without
-data flow analysis) have to be executed after any existing branch
-delay slot filler insns.  It is also unknown whether such a
-transformation would actually be profitable.  Note that the existing
-code only cares for branches with (some) filled delay slots.  */
-if (crtl->epilogue_delay_list != NULL)
-return;
-#endif
 /* See if there is a RETURN insn in the function other than the one we
 made for END_OF_FUNCTION_LABEL.  If so, set up anything we can't change
 into a RETURN to jump to it.  */
 for (insn = first; insn; insn = NEXT_INSN (insn))
-if (JUMP_P (insn) && GET_CODE (PATTERN (insn)) == RETURN)
+if (JUMP_P (insn) && ANY_RETURN_P (PATTERN (insn)))
 {
-	real_return_label = get_label_before (insn);
+	rtx t = get_label_before (insn, NULL_RTX);
+	if (PATTERN (insn) == ret_rtx)
+	  real_return_label = t;
+	else
+	  real_simple_return_label = t;
 	break;
 }
 /* Show an extra usage of REAL_RETURN_LABEL so it won't go away if it
 was equal to END_OF_FUNCTION_LABEL.  */
-LABEL_NUSES (real_return_label)++;
+if (real_return_label)
+LABEL_NUSES (real_return_label)++;
+if (real_simple_return_label)
+LABEL_NUSES (real_simple_return_label)++;
 /* Clear the list of insns to fill so we can use it.  */
 obstack_free (&unfilled_slots_obstack, unfilled_firstobj);
 for (insn = first; insn; insn = NEXT_INSN (insn))
 {
 int flags;
+rtx kind, real_label;
 /* Only look at filled JUMP_INSNs that go to the end of function
 	 label.  */
-if (!NONJUMP_INSN_P (insn)
+if (!NONJUMP_INSN_P (insn))
-	  || GET_CODE (PATTERN (insn)) != SEQUENCE
-	  || !JUMP_P (XVECEXP (PATTERN (insn), 0, 0))
-	  || JUMP_LABEL (XVECEXP (PATTERN (insn), 0, 0)) != end_of_function_label)
 	continue;
-pat = PATTERN (insn);
+if (GET_CODE (PATTERN (insn)) != SEQUENCE)
-jump_insn = XVECEXP (pat, 0, 0);
+	continue;
+rtx_sequence *pat = as_a <rtx_sequence *> (PATTERN (insn));
+if (!jump_to_label_p (pat->insn (0)))
+	continue;
+if (JUMP_LABEL (pat->insn (0)) == function_return_label)
+	{
+	  kind = ret_rtx;
+	  real_label = real_return_label;
+	}
+else if (JUMP_LABEL (pat->insn (0)) == function_simple_return_label)
+	{
+	  kind = simple_return_rtx;
+	  real_label = real_simple_return_label;
+	}
+else
+	continue;
+jump_insn = as_a <rtx_jump_insn *> (pat->insn (0));
 /* If we can't make the jump into a RETURN, try to redirect it to the best
 	 RETURN and go on to the next insn.  */
-if (! reorg_redirect_jump (jump_insn, NULL_RTX))
+if (!reorg_redirect_jump (jump_insn, kind))
 	{
 	  /* Make sure redirecting the jump will not invalidate the delay
 	     slot insns.  */
-	  if (redirect_with_delay_slots_safe_p (jump_insn,
+	  if (redirect_with_delay_slots_safe_p (jump_insn, real_label, insn))
-						real_return_label,
+	    reorg_redirect_jump (jump_insn, real_label);
-						insn))
-	    reorg_redirect_jump (jump_insn, real_return_label);
 	  continue;
 	}
 /* See if this RETURN can accept the insns current in its delay slot.
 	 It can if it has more or an equal number of slots and the contents
 slots = num_delay_slots (jump_insn);
 if (slots >= XVECLEN (pat, 0) - 1)
 	{
 	  for (i = 1; i < XVECLEN (pat, 0); i++)
 	    if (! (
-#ifdef ANNUL_IFFALSE_SLOTS
+#if ANNUL_IFFALSE_SLOTS
 		   (INSN_ANNULLED_BRANCH_P (jump_insn)
-		    && INSN_FROM_TARGET_P (XVECEXP (pat, 0, i)))
+		    && INSN_FROM_TARGET_P (pat->insn (i)))
 		   ? eligible_for_annul_false (jump_insn, i - 1,
-					       XVECEXP (pat, 0, i), flags) :
+					       pat->insn (i), flags) :
 #endif
-#ifdef ANNUL_IFTRUE_SLOTS
+#if ANNUL_IFTRUE_SLOTS
 		   (INSN_ANNULLED_BRANCH_P (jump_insn)
-		    && ! INSN_FROM_TARGET_P (XVECEXP (pat, 0, i)))
+		    && ! INSN_FROM_TARGET_P (pat->insn (i)))
 		   ? eligible_for_annul_true (jump_insn, i - 1,
-					      XVECEXP (pat, 0, i), flags) :
+					      pat->insn (i), flags) :
 #endif
 		   eligible_for_delay (jump_insn, i - 1,
-				       XVECEXP (pat, 0, i), flags)))
+				       pat->insn (i), flags)))
 	      break;
 	}
 else
 	i = 0;
 /* We have to do something with this insn.  If it is an unconditional
 	 RETURN, delete the SEQUENCE and output the individual insns,
 	 followed by the RETURN.  Then set things up so we try to find
 	 insns for its delay slots, if it needs some.  */
-if (GET_CODE (PATTERN (jump_insn)) == RETURN)
+if (ANY_RETURN_P (PATTERN (jump_insn)))
 	{
-	  rtx prev = PREV_INSN (insn);
+	  rtx_insn *prev = PREV_INSN (insn);
 	  delete_related_insns (insn);
 	  for (i = 1; i < XVECLEN (pat, 0); i++)
 	    prev = emit_insn_after (PATTERN (XVECEXP (pat, 0, i)), prev);
 	    obstack_ptr_grow (&unfilled_slots_obstack, insn);
 	}
 else
 	/* It is probably more efficient to keep this with its current
 	   delay slot as a branch to a RETURN.  */
-	reorg_redirect_jump (jump_insn, real_return_label);
+	reorg_redirect_jump (jump_insn, real_label);
 }
 /* Now delete REAL_RETURN_LABEL if we never used it.  Then try to fill any
 new delay slots we have created.  */
-if (--LABEL_NUSES (real_return_label) == 0)
+if (real_return_label != NULL_RTX && --LABEL_NUSES (real_return_label) == 0)
 delete_related_insns (real_return_label);
+if (real_simple_return_label != NULL_RTX
+&& --LABEL_NUSES (real_simple_return_label) == 0)
+delete_related_insns (real_simple_return_label);
 fill_simple_delay_slots (1);
 fill_simple_delay_slots (0);
 }
-#endif
 /* Try to find insns to place in delay slots.  */
-void
+static void
-dbr_schedule (rtx first)
+dbr_schedule (rtx_insn *first)
 {
-rtx insn, next, epilogue_insn = 0;
+rtx_insn *insn, *next, *epilogue_insn = 0;
 int i;
+bool need_return_insns;
 /* If the current function has no insns other than the prologue and
 epilogue, then do not try to fill any delay slots.  */
-if (n_basic_blocks == NUM_FIXED_BLOCKS)
+if (n_basic_blocks_for_fn (cfun) == NUM_FIXED_BLOCKS)
 return;
 /* Find the highest INSN_UID and allocate and initialize our map from
 INSN_UID's to position in code.  */
 for (max_uid = 0, insn = first; insn; insn = NEXT_INSN (insn))
 for (insn = next_active_insn (first); insn; insn = next_active_insn (insn))
 {
 rtx target;
-INSN_ANNULLED_BRANCH_P (insn) = 0;
-INSN_FROM_TARGET_P (insn) = 0;
 /* Skip vector tables.  We can't get attributes for them.  */
 if (JUMP_TABLE_DATA_P (insn))
 	continue;
+if (JUMP_P (insn))
+INSN_ANNULLED_BRANCH_P (insn) = 0;
+INSN_FROM_TARGET_P (insn) = 0;
 if (num_delay_slots (insn) > 0)
 	obstack_ptr_grow (&unfilled_slots_obstack, insn);
 /* Ensure all jumps go to the last of a set of consecutive labels.  */
 if (JUMP_P (insn)
 	  && (condjump_p (insn) || condjump_in_parallel_p (insn))
-	  && JUMP_LABEL (insn) != 0
+	  && !ANY_RETURN_P (JUMP_LABEL (insn))
 	  && ((target = skip_consecutive_labels (JUMP_LABEL (insn)))
 	      != JUMP_LABEL (insn)))
-	redirect_jump (insn, target, 1);
+	redirect_jump (as_a <rtx_jump_insn *> (insn), target, 1);
 }
 init_resource_info (epilogue_insn);
 /* Show we haven't computed an end-of-function label yet.  */
-end_of_function_label = 0;
+function_return_label = function_simple_return_label = NULL;
 /* Initialize the statistics for this function.  */
 memset (num_insns_needing_delays, 0, sizeof num_insns_needing_delays);
 memset (num_filled_delays, 0, sizeof num_filled_delays);
 reorg_pass_number < MAX_REORG_PASSES;
 reorg_pass_number++)
 {
 fill_simple_delay_slots (1);
 fill_simple_delay_slots (0);
-fill_eager_delay_slots ();
+if (!targetm.no_speculation_in_delay_slots_p ())
+	fill_eager_delay_slots ();
 relax_delay_slots (first);
 }
 /* If we made an end of function label, indicate that it is now
 safe to delete it by undoing our prior adjustment to LABEL_NUSES.
 If it is now unused, delete it.  */
-if (end_of_function_label && --LABEL_NUSES (end_of_function_label) == 0)
+if (function_return_label && --LABEL_NUSES (function_return_label) == 0)
-delete_related_insns (end_of_function_label);
+delete_related_insns (function_return_label);
+if (function_simple_return_label
-#ifdef HAVE_return
+&& --LABEL_NUSES (function_simple_return_label) == 0)
-if (HAVE_return && end_of_function_label != 0)
+delete_related_insns (function_simple_return_label);
+need_return_insns = false;
+need_return_insns |= targetm.have_return () && function_return_label != 0;
+need_return_insns |= (targetm.have_simple_return ()
+			&& function_simple_return_label != 0);
+if (need_return_insns)
 make_return_insns (first);
-#endif
 /* Delete any USE insns made by update_block; subsequent passes don't need
 them or know how to deal with them.  */
 for (insn = first; insn; insn = next)
 {
 	}
 memset (total_delay_slots, 0, sizeof total_delay_slots);
 memset (total_annul_slots, 0, sizeof total_annul_slots);
 for (insn = first; insn; insn = NEXT_INSN (insn))
 	{
-	  if (! INSN_DELETED_P (insn)
+	  if (! insn->deleted ()
 	      && NONJUMP_INSN_P (insn)
 	      && GET_CODE (PATTERN (insn)) != USE
 	      && GET_CODE (PATTERN (insn)) != CLOBBER)
 	    {
 	      if (GET_CODE (PATTERN (insn)) == SEQUENCE)
 		{
+rtx control;
 		  j = XVECLEN (PATTERN (insn), 0) - 1;
 		  if (j > MAX_DELAY_HISTOGRAM)
 		    j = MAX_DELAY_HISTOGRAM;
-		  if (INSN_ANNULLED_BRANCH_P (XVECEXP (PATTERN (insn), 0, 0)))
+control = XVECEXP (PATTERN (insn), 0, 0);
+		  if (JUMP_P (control) && INSN_ANNULLED_BRANCH_P (control))
 		    total_annul_slots[j]++;
 		  else
 		    total_delay_slots[j]++;
 		}
 	      else if (num_delay_slots (insn) > 0)
 	      need_comma = 1;
 	      fprintf (dump_file, "%d got %d delays", total_delay_slots[j], j);
 	    }
 	}
 fprintf (dump_file, "\n");
-#if defined (ANNUL_IFTRUE_SLOTS) || defined (ANNUL_IFFALSE_SLOTS)
-fprintf (dump_file, ";; Reorg annuls: ");
+if (ANNUL_IFTRUE_SLOTS || ANNUL_IFFALSE_SLOTS)
-need_comma = 0;
+	{
-for (j = 0; j < MAX_DELAY_HISTOGRAM + 1; j++)
+	  fprintf (dump_file, ";; Reorg annuls: ");
-	{
+	  need_comma = 0;
-	  if (total_annul_slots[j])
+	  for (j = 0; j < MAX_DELAY_HISTOGRAM + 1; j++)
 	    {
-	      if (need_comma)
+	      if (total_annul_slots[j])
-		fprintf (dump_file, ", ");
+		{
-	      need_comma = 1;
+		  if (need_comma)
-	      fprintf (dump_file, "%d got %d delays", total_annul_slots[j], j);
+		    fprintf (dump_file, ", ");
+		  need_comma = 1;
+		  fprintf (dump_file, "%d got %d delays", total_annul_slots[j], j);
+		}
 	    }
-	}
+	  fprintf (dump_file, "\n");
+	}
 fprintf (dump_file, "\n");
-#endif
+}
-fprintf (dump_file, "\n");
-}
+if (!sibling_labels.is_empty ())
+{
-/* For all JUMP insns, fill in branch prediction notes, so that during
+update_alignments (sibling_labels);
-assembler output a target can set branch prediction bits in the code.
+sibling_labels.release ();
-We have to do this now, as up until this point the destinations of
+}
-JUMPS can be moved around and changed, but past right here that cannot
-happen.  */
-for (insn = first; insn; insn = NEXT_INSN (insn))
-{
-int pred_flags;
-if (NONJUMP_INSN_P (insn))
-	{
-	  rtx pat = PATTERN (insn);
-	  if (GET_CODE (pat) == SEQUENCE)
-	    insn = XVECEXP (pat, 0, 0);
-	}
-if (!JUMP_P (insn))
-	continue;
-pred_flags = get_jump_flags (insn, JUMP_LABEL (insn));
-add_reg_note (insn, REG_BR_PRED, GEN_INT (pred_flags));
-}
 free_resource_info ();
 free (uid_to_ruid);
-#ifdef DELAY_SLOTS_FOR_EPILOGUE
-/* SPARC assembler, for instance, emit warning when debug info is output
-into the delay slot.  */
-{
-rtx link;
-for (link = crtl->epilogue_delay_list;
-link;
-link = XEXP (link, 1))
-INSN_LOCATOR (XEXP (link, 0)) = 0;
-}
-#endif
 crtl->dbr_scheduled_p = true;
 }
-#endif /* DELAY_SLOTS */
-static bool
-gate_handle_delay_slots (void)
-{
-#ifdef DELAY_SLOTS
-/* At -O0 dataflow info isn't updated after RA.  */
-return optimize > 0 && flag_delayed_branch && !crtl->dbr_scheduled_p;
-#else
-return 0;
-#endif
-}
 /* Run delay slot optimization.  */
 static unsigned int
 rest_of_handle_delay_slots (void)
 {
-#ifdef DELAY_SLOTS
+if (DELAY_SLOTS)
 dbr_schedule (get_insns ());
-#endif
 return 0;
 }
-struct rtl_opt_pass pass_delay_slots =
+namespace {
-{
-{
+const pass_data pass_data_delay_slots =
-RTL_PASS,
+{
-"dbr",                                /* name */
+RTL_PASS, /* type */
-gate_handle_delay_slots,              /* gate */
+"dbr", /* name */
-rest_of_handle_delay_slots,           /* execute */
+OPTGROUP_NONE, /* optinfo_flags */
-NULL,                                 /* sub */
+TV_DBR_SCHED, /* tv_id */
-NULL,                                 /* next */
+0, /* properties_required */
-0,                                    /* static_pass_number */
+0, /* properties_provided */
-TV_DBR_SCHED,                         /* tv_id */
+0, /* properties_destroyed */
-0,                                    /* properties_required */
+0, /* todo_flags_start */
-0,                                    /* properties_provided */
+0, /* todo_flags_finish */
-0,                                    /* properties_destroyed */
-0,                                    /* todo_flags_start */
-TODO_dump_func |
-TODO_ggc_collect                      /* todo_flags_finish */
-}
 };
+class pass_delay_slots : public rtl_opt_pass
+{
+public:
+pass_delay_slots (gcc::context *ctxt)
+: rtl_opt_pass (pass_data_delay_slots, ctxt)
+{}
+/* opt_pass methods: */
+virtual bool gate (function *);
+virtual unsigned int execute (function *)
+{
+return rest_of_handle_delay_slots ();
+}
+}; // class pass_delay_slots
+bool
+pass_delay_slots::gate (function *)
+{
+/* At -O0 dataflow info isn't updated after RA.  */
+if (DELAY_SLOTS)
+return optimize > 0 && flag_delayed_branch && !crtl->dbr_scheduled_p;
+return false;
+}
+} // anon namespace
+rtl_opt_pass *
+make_pass_delay_slots (gcc::context *ctxt)
+{
+return new pass_delay_slots (ctxt);
+}
 /* Machine dependent reorg pass.  */
-static bool
-gate_handle_machine_reorg (void)
+namespace {
-{
-return targetm.machine_dependent_reorg != 0;
+const pass_data pass_data_machine_reorg =
-}
+{
+RTL_PASS, /* type */
+"mach", /* name */
-static unsigned int
+OPTGROUP_NONE, /* optinfo_flags */
-rest_of_handle_machine_reorg (void)
+TV_MACH_DEP, /* tv_id */
-{
+0, /* properties_required */
-targetm.machine_dependent_reorg ();
+0, /* properties_provided */
-return 0;
+0, /* properties_destroyed */
-}
+0, /* todo_flags_start */
+0, /* todo_flags_finish */
-struct rtl_opt_pass pass_machine_reorg =
-{
-{
-RTL_PASS,
-"mach",                               /* name */
-gate_handle_machine_reorg,            /* gate */
-rest_of_handle_machine_reorg,         /* execute */
-NULL,                                 /* sub */
-NULL,                                 /* next */
-0,                                    /* static_pass_number */
-TV_MACH_DEP,                          /* tv_id */
-0,                                    /* properties_required */
-0,                                    /* properties_provided */
-0,                                    /* properties_destroyed */
-0,                                    /* todo_flags_start */
-TODO_dump_func |
-TODO_ggc_collect                      /* todo_flags_finish */
-}
 };
+class pass_machine_reorg : public rtl_opt_pass
+{
+public:
+pass_machine_reorg (gcc::context *ctxt)
+: rtl_opt_pass (pass_data_machine_reorg, ctxt)
+{}
+/* opt_pass methods: */
+virtual bool gate (function *)
+{
+return targetm.machine_dependent_reorg != 0;
+}
+virtual unsigned int execute (function *)
+{
+targetm.machine_dependent_reorg ();
+return 0;
+}
+}; // class pass_machine_reorg
+} // anon namespace
+rtl_opt_pass *
+make_pass_machine_reorg (gcc::context *ctxt)
+{
+return new pass_machine_reorg (ctxt);
+}

Mercurial > hg > CbC > CbC_gcc

comparison gcc/reorg.c @ 111:04ced10e8804