* rtlanal.c (label_is_jump_target_p): Return true for a matching

	REG_LABEL_TARGET.
	* reorg.c (fill_slots_from_thread): Correct last change to use
	NULL_RTX, not NULL.  Outside of REG_NOTES loop, increase and
	decrease LABEL_NUSES for JUMP_LABEL (trial), not XEXP (note, 0).
	* jump.c (mark_jump_label_1): Add comment for last change
	regarding JUMP_LABEL setting.
	* gcse.c (add_label_notes): Remove conditional that the label is
	mentioned in insn before adding regnote.
	* sched-rgn.c (is_cfg_nonregular): Don't return 1 for a
	single_set insn only feeding a label to a jump through a
	register that dies there.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@130398 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 4c34686..670c0ac 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,18 @@
+2007-11-24  Hans-Peter Nilsson  <hp@axis.com>
+
+       * rtlanal.c (label_is_jump_target_p): Return true for a matching
+       REG_LABEL_TARGET.
+       * reorg.c (fill_slots_from_thread): Correct last change to use
+       NULL_RTX, not NULL.  Outside of REG_NOTES loop, increase and
+       decrease LABEL_NUSES for JUMP_LABEL (trial), not XEXP (note, 0).
+       * jump.c (mark_jump_label_1): Add comment for last change
+       regarding JUMP_LABEL setting.
+       * gcse.c (add_label_notes): Remove conditional that the label is
+       mentioned in insn before adding regnote.
+       * sched-rgn.c (is_cfg_nonregular): Don't return 1 for a
+       single_set insn only feeding a label to a jump through a
+       register that dies there.
+
 2007-11-23  Dirk Mueller  <dmueller@suse.de>
        Richard Guenther <rguenther@suse.de>
 

diff --git a/gcc/gcse.c b/gcc/gcse.c
index 84c0994..db7e03c 100644 (file)
--- a/gcc/gcse.c
+++ b/gcc/gcse.c
@@ -4614,18 +4614,16 @@ add_label_notes (rtx x, rtx insn)
         We no longer ignore such label references (see LABEL_REF handling in
         mark_jump_label for additional information).  */
 
-       if (reg_mentioned_p (XEXP (x, 0), insn))
-         {
-           /* There's no reason for current users to emit jump-insns
-              with such a LABEL_REF, so we don't have to handle
-              REG_LABEL_TARGET notes.  */
-           gcc_assert (!JUMP_P (insn));
-           REG_NOTES (insn)
-             = gen_rtx_INSN_LIST (REG_LABEL_OPERAND, XEXP (x, 0),
-                                  REG_NOTES (insn));
-           if (LABEL_P (XEXP (x, 0)))
-             LABEL_NUSES (XEXP (x, 0))++;
-         }
+      /* There's no reason for current users to emit jump-insns with
+        such a LABEL_REF, so we don't have to handle REG_LABEL_TARGET
+        notes.  */
+      gcc_assert (!JUMP_P (insn));
+      REG_NOTES (insn)
+       = gen_rtx_INSN_LIST (REG_LABEL_OPERAND, XEXP (x, 0),
+                            REG_NOTES (insn));
+      if (LABEL_P (XEXP (x, 0)))
+       LABEL_NUSES (XEXP (x, 0))++;
+
       return;
     }
 

diff --git a/gcc/jump.c b/gcc/jump.c
index e17f148..4564cd1 100644 (file)
--- a/gcc/jump.c
+++ b/gcc/jump.c
@@ -1051,6 +1051,9 @@ mark_jump_label_1 (rtx x, rtx insn, bool in_mem, bool is_target)
        if (insn)
          {
            if (is_target
+               /* Do not change a previous setting of JUMP_LABEL.  If the
+                  JUMP_LABEL slot is occupied by a different label,
+                  create a note for this label.  */
                && (JUMP_LABEL (insn) == NULL || JUMP_LABEL (insn) == label))
              JUMP_LABEL (insn) = label;
            else

diff --git a/gcc/reorg.c b/gcc/reorg.c
index 51acaa3..985c118 100644 (file)
--- a/gcc/reorg.c
+++ b/gcc/reorg.c
@@ -2740,7 +2740,7 @@ fill_slots_from_thread (rtx insn, rtx condition, rtx thread,
                         temporarily increment the use count on any referenced
                         label lest it be deleted by delete_related_insns.  */
                      for (note = REG_NOTES (trial);
-                          note != NULL;
+                          note != NULL_RTX;
                           note = XEXP (note, 1))
                        if (REG_NOTE_KIND (note) == REG_LABEL_OPERAND
                            || REG_NOTE_KIND (note) == REG_LABEL_TARGET)
@@ -2754,12 +2754,12 @@ fill_slots_from_thread (rtx insn, rtx condition, rtx thread,
                                          == REG_LABEL_OPERAND);
                          }
                      if (JUMP_P (trial) && JUMP_LABEL (trial))
-                       LABEL_NUSES (XEXP (note, 0))++;
+                       LABEL_NUSES (JUMP_LABEL (trial))++;
 
                      delete_related_insns (trial);
 
                      for (note = REG_NOTES (trial);
-                          note != NULL;
+                          note != NULL_RTX;
                           note = XEXP (note, 1))
                        if (REG_NOTE_KIND (note) == REG_LABEL_OPERAND
                            || REG_NOTE_KIND (note) == REG_LABEL_TARGET)
@@ -2773,7 +2773,7 @@ fill_slots_from_thread (rtx insn, rtx condition, rtx thread,
                                          == REG_LABEL_OPERAND);
                          }
                      if (JUMP_P (trial) && JUMP_LABEL (trial))
-                       LABEL_NUSES (XEXP (note, 0))--;
+                       LABEL_NUSES (JUMP_LABEL (trial))--;
                    }
                  else
                    new_thread = next_active_insn (trial);

diff --git a/gcc/rtlanal.c b/gcc/rtlanal.c
index 0e0f7e3..d9e60d3 100644 (file)
--- a/gcc/rtlanal.c
+++ b/gcc/rtlanal.c
@@ -3434,6 +3434,9 @@ label_is_jump_target_p (const_rtx label, const_rtx jump_insn)
          return true;
     }
 
+  if (find_reg_note (jump_insn, REG_LABEL_TARGET, label))
+    return true;
+
   return false;
 }
 

diff --git a/gcc/sched-rgn.c b/gcc/sched-rgn.c
index 12f2e66..b340bd5 100644 (file)
--- a/gcc/sched-rgn.c
+++ b/gcc/sched-rgn.c
@@ -320,16 +320,40 @@ is_cfg_nonregular (void)
   FOR_EACH_BB (b)
     FOR_BB_INSNS (b, insn)
       {
-       /* Check for labels referred to but (at least not directly) as
-          jump targets.  */
-       if (INSN_P (insn)
-           && find_reg_note (insn, REG_LABEL_OPERAND, NULL_RTX))
-         return 1;
+       rtx note, next, set, dest;
 
        /* If this function has a computed jump, then we consider the cfg
           not well structured.  */
        if (JUMP_P (insn) && computed_jump_p (insn))
          return 1;
+
+       if (!INSN_P (insn))
+         continue;
+
+       note = find_reg_note (insn, REG_LABEL_OPERAND, NULL_RTX);
+       if (note == NULL_RTX)
+         continue;
+
+       /* For that label not to be seen as a referred-to label, this
+          must be a single-set which is feeding a jump *only*.  This
+          could be a conditional jump with the label split off for
+          machine-specific reasons or a casesi/tablejump.  */
+       next = next_nonnote_insn (insn);
+       if (next == NULL_RTX
+           || !JUMP_P (next)
+           || (JUMP_LABEL (next) != XEXP (note, 0)
+               && find_reg_note (next, REG_LABEL_TARGET,
+                                 XEXP (note, 0)) == NULL_RTX)
+           || BLOCK_FOR_INSN (insn) != BLOCK_FOR_INSN (next))
+         return 1;
+
+       set = single_set (insn);
+       if (set == NULL_RTX)
+         return 1;
+
+       dest = SET_DEST (set);
+       if (!REG_P (dest) || !dead_or_set_p (next, dest))
+         return 1;
       }
 
   /* Unreachable loops with more than one basic block are detected