recog.c (verify_changes, [...]): New functions, broken out of apply_change_group.

	* recog.c (verify_changes, confirm_change_group): New functions,
	broken out of apply_change_group.
	(apply_change_group): Use them.
	* recog.h (verify_change, confirm_change_group): Declare.
	* rtl.h (redirect_jump_2): Declare.
	* jump.c (redirect_exp, invert_exp): Delete.
	(invert_exp_1): Take second parameter.  Return value.  Changed caller.
	(redirect_jump_2): New function, broken out of redirect_jump.
	(redirect_jump): Use redirect_jump_1 and redirect_jump_2.
	(invert_jump): Use invert_jump_1 and redirect_jump_2.
	* ifcvt.c (dead_or_predicable): Use redirect_jump_2.

From-SVN: r95813

gcc/ChangeLog

+2005-03-02  J"orn Rennecke <joern.rennecke@st.com>
+
+	* recog.c (verify_changes, confirm_change_group): New functions,
+	broken out of apply_change_group.
+	(apply_change_group): Use them.
+	* recog.h (verify_change, confirm_change_group): Declare.
+	* rtl.h (redirect_jump_2): Declare.
+	* jump.c (redirect_exp, invert_exp): Delete.
+	(invert_exp_1): Take second parameter.  Return value.  Changed caller.
+	(redirect_jump_2): New function, broken out of redirect_jump.
+	(redirect_jump): Use redirect_jump_1 and redirect_jump_2.
+	(invert_jump): Use invert_jump_1 and redirect_jump_2.
+	* ifcvt.c (dead_or_predicable): Use redirect_jump_2.
+
 2005-03-02  Geoffrey Keating  <geoffk@apple.com>
 
 	* varasm.c (named_section): Use xstrdup rather than doing it by

gcc/ifcvt.c

@@ -3258,13 +3258,7 @@ dead_or_predicable (basic_block test_bb, basic_block merge_bb,
 
   if (other_bb != new_dest)
     {
-      if (old_dest)
-	LABEL_NUSES (old_dest) -= 1;
-      if (new_label)
-	LABEL_NUSES (new_label) += 1;
-      JUMP_LABEL (jump) = new_label;
-      if (reversep)
-	invert_br_probabilities (jump);
+      redirect_jump_2 (jump, old_dest, new_label, -1, reversep);
 
       redirect_edge_succ (BRANCH_EDGE (test_bb), new_dest);
       if (reversep)

gcc/jump.c

@@ -67,9 +67,7 @@ static void init_label_info (rtx);
 static void mark_all_labels (rtx);
 static void delete_computation (rtx);
 static void redirect_exp_1 (rtx *, rtx, rtx, rtx);
-static int redirect_exp (rtx, rtx, rtx);
-static void invert_exp_1 (rtx);
-static int invert_exp (rtx);
+static int invert_exp_1 (rtx, rtx);
 static int returnjump_p_1 (rtx *, void *);
 static void delete_prior_computation (rtx, rtx);
 
@@ -1570,25 +1568,6 @@ redirect_exp_1 (rtx *loc, rtx olabel, rtx nlabel, rtx insn)
     }
 }
 
-/* Similar, but apply the change group and report success or failure.  */
-
-static int
-redirect_exp (rtx olabel, rtx nlabel, rtx insn)
-{
-  rtx *loc;
-
-  if (GET_CODE (PATTERN (insn)) == PARALLEL)
-    loc = &XVECEXP (PATTERN (insn), 0, 0);
-  else
-    loc = &PATTERN (insn);
-
-  redirect_exp_1 (loc, olabel, nlabel, insn);
-  if (num_validated_changes () == 0)
-    return 0;
-
-  return apply_change_group ();
-}
-
 /* Make JUMP go to NLABEL instead of where it jumps now.  Accrue
    the modifications into the change group.  Return false if we did
    not see how to do that.  */
@@ -1622,14 +1601,28 @@ int
 redirect_jump (rtx jump, rtx nlabel, int delete_unused)
 {
   rtx olabel = JUMP_LABEL (jump);
-  rtx note;
 
   if (nlabel == olabel)
     return 1;
 
-  if (! redirect_exp (olabel, nlabel, jump))
+  if (! redirect_jump_1 (jump, nlabel) || ! apply_change_group ())
     return 0;
 
+  redirect_jump_2 (jump, olabel, nlabel, delete_unused, 0);
+  return 1;
+}
+
+/* Fix up JUMP_LABEL and label ref counts after OLABEL has been replaced with
+   NLABEL in JUMP.  If DELETE_UNUSED is non-negative, copy a
+   NOTE_INSN_FUNCTION_END found after OLABEL to the place after NLABEL.
+   If DELETE_UNUSED is positive, delete related insn to OLABEL if its ref
+   count has dropped to zero.  */
+void
+redirect_jump_2 (rtx jump, rtx olabel, rtx nlabel, int delete_unused,
+		 int invert)
+{
+  rtx note;
+
   JUMP_LABEL (jump) = nlabel;
   if (nlabel)
     ++LABEL_NUSES (nlabel);
@@ -1637,24 +1630,13 @@ redirect_jump (rtx jump, rtx nlabel, int delete_unused)
   /* Update labels in any REG_EQUAL note.  */
   if ((note = find_reg_note (jump, REG_EQUAL, NULL_RTX)) != NULL_RTX)
     {
-      if (nlabel && olabel)
+      if (!nlabel || (invert && !invert_exp_1 (XEXP (note, 0), jump)))
+	remove_note (jump, note);
+      else
 	{
-	  rtx dest = XEXP (note, 0);
-
-	  if (GET_CODE (dest) == IF_THEN_ELSE)
-	    {
-	      if (GET_CODE (XEXP (dest, 1)) == LABEL_REF
-		  && XEXP (XEXP (dest, 1), 0) == olabel)
-		XEXP (XEXP (dest, 1), 0) = nlabel;
-	      if (GET_CODE (XEXP (dest, 2)) == LABEL_REF
-		  && XEXP (XEXP (dest, 2), 0) == olabel)
-		XEXP (XEXP (dest, 2), 0) = nlabel;
-	    }
-	  else
-	    remove_note (jump, note);
+	  redirect_exp_1 (&XEXP (note, 0), olabel, nlabel, jump);
+	  confirm_change_group ();
 	}
-      else
-        remove_note (jump, note);
     }
 
   /* If we're eliding the jump over exception cleanups at the end of a
@@ -1662,31 +1644,24 @@ redirect_jump (rtx jump, rtx nlabel, int delete_unused)
   if (olabel && nlabel
       && NEXT_INSN (olabel)
       && NOTE_P (NEXT_INSN (olabel))
-      && NOTE_LINE_NUMBER (NEXT_INSN (olabel)) == NOTE_INSN_FUNCTION_END)
+      && NOTE_LINE_NUMBER (NEXT_INSN (olabel)) == NOTE_INSN_FUNCTION_END
+      && delete_unused >= 0)
     emit_note_after (NOTE_INSN_FUNCTION_END, nlabel);
 
-  if (olabel && --LABEL_NUSES (olabel) == 0 && delete_unused
+  if (olabel && --LABEL_NUSES (olabel) == 0 && delete_unused > 0
       /* Undefined labels will remain outside the insn stream.  */
       && INSN_UID (olabel))
     delete_related_insns (olabel);
-
-  return 1;
+  if (invert)
+    invert_br_probabilities (jump);
 }
 
-/* Invert the jump condition of rtx X contained in jump insn, INSN.
-   Accrue the modifications into the change group.  */
-
-static void
-invert_exp_1 (rtx insn)
+/* Invert the jump condition X contained in jump insn INSN.  Accrue the
+   modifications into the change group.  Return nonzero for success.  */
+static int
+invert_exp_1 (rtx x, rtx insn)
 {
-  RTX_CODE code;
-  rtx x = pc_set (insn);
-
-  if (!x)
-    abort ();
-  x = SET_SRC (x);
-
-  code = GET_CODE (x);
+  RTX_CODE code = GET_CODE (x);
 
   if (code == IF_THEN_ELSE)
     {
@@ -1708,30 +1683,16 @@ invert_exp_1 (rtx insn)
 					   GET_MODE (comp), XEXP (comp, 0),
 					   XEXP (comp, 1)),
 			   1);
-	  return;
+	  return 1;
 	}
 
       tem = XEXP (x, 1);
       validate_change (insn, &XEXP (x, 1), XEXP (x, 2), 1);
       validate_change (insn, &XEXP (x, 2), tem, 1);
+      return 1;
     }
   else
-    abort ();
-}
-
-/* Invert the jump condition of conditional jump insn, INSN.
-
-   Return 1 if we can do so, 0 if we cannot find a way to do so that
-   matches a pattern.  */
-
-static int
-invert_exp (rtx insn)
-{
-  invert_exp_1 (insn);
-  if (num_validated_changes () == 0)
     return 0;
-
-  return apply_change_group ();
 }
 
 /* Invert the condition of the jump JUMP, and make it jump to label
@@ -1742,10 +1703,12 @@ invert_exp (rtx insn)
 int
 invert_jump_1 (rtx jump, rtx nlabel)
 {
+  rtx x = pc_set (jump);
   int ochanges;
 
   ochanges = num_validated_changes ();
-  invert_exp_1 (jump);
+  if (!x || !invert_exp_1 (SET_SRC (x), jump))
+    abort ();
   if (num_validated_changes () == ochanges)
     return 0;
 
@@ -1758,30 +1721,14 @@ invert_jump_1 (rtx jump, rtx nlabel)
 int
 invert_jump (rtx jump, rtx nlabel, int delete_unused)
 {
-  /* We have to either invert the condition and change the label or
-     do neither.  Either operation could fail.  We first try to invert
-     the jump. If that succeeds, we try changing the label.  If that fails,
-     we invert the jump back to what it was.  */
-
-  if (! invert_exp (jump))
-    return 0;
+  rtx olabel = JUMP_LABEL (jump);
 
-  if (redirect_jump (jump, nlabel, delete_unused))
+  if (invert_jump_1 (jump, nlabel) && apply_change_group ())
     {
-      /* Remove REG_EQUAL note if we have one.  */
-      rtx note = find_reg_note (jump, REG_EQUAL, NULL_RTX);
-      if (note)
-	remove_note (jump, note);
-
-      invert_br_probabilities (jump);
-
+      redirect_jump_2 (jump, olabel, nlabel, delete_unused, 1);
       return 1;
     }
-
-  if (! invert_exp (jump))
-    /* This should just be putting it back the way it was.  */
-    abort ();
-
+  cancel_changes (0);
   return 0;
 }
 

gcc/recog.c

@@ -294,11 +294,11 @@ num_changes_pending (void)
   return num_changes;
 }
 
-/* Apply a group of changes previously issued with `validate_change'.
+/* Tentatively apply the changes numbered NUM and up.
    Return 1 if all changes are valid, zero otherwise.  */
 
 int
-apply_change_group (void)
+verify_changes (int num)
 {
   int i;
   rtx last_validated = NULL_RTX;
@@ -312,7 +312,7 @@ apply_change_group (void)
      we also require that the operands meet the constraints for
      the insn.  */
 
-  for (i = 0; i < num_changes; i++)
+  for (i = num; i < num_changes; i++)
     {
       rtx object = changes[i].object;
 
@@ -376,17 +376,38 @@ apply_change_group (void)
       last_validated = object;
     }
 
-  if (i == num_changes)
-    {
-      basic_block bb;
+  return (i == num_changes);
+}
 
-      for (i = 0; i < num_changes; i++)
-	if (changes[i].object
-	    && INSN_P (changes[i].object)
-	    && (bb = BLOCK_FOR_INSN (changes[i].object)))
-	  bb->flags |= BB_DIRTY;
+/* A group of changes has previously been issued with validate_change and
+   verified with verify_changes.  Update the BB_DIRTY flags of the affected
+   blocks, and clear num_changes.  */
 
-      num_changes = 0;
+void
+confirm_change_group (void)
+{
+  int i;
+  basic_block bb;
+
+  for (i = 0; i < num_changes; i++)
+    if (changes[i].object
+	&& INSN_P (changes[i].object)
+	&& (bb = BLOCK_FOR_INSN (changes[i].object)))
+      bb->flags |= BB_DIRTY;
+
+  num_changes = 0;
+}
+
+/* Apply a group of changes previously issued with `validate_change'.
+   If all changes are valid, call confirm_change_group and return 1,
+   otherwise, call cancel_changes and return 0.  */
+
+int
+apply_change_group (void)
+{
+  if (verify_changes (0))
+    {
+      confirm_change_group ();
       return 1;
     }
   else
@@ -396,6 +417,7 @@ apply_change_group (void)
     }
 }
 
+
 /* Return the number of changes so far in the current group.  */
 
 int

gcc/recog.h

@@ -75,6 +75,8 @@ extern int check_asm_operands (rtx);
 extern int asm_operand_ok (rtx, const char *);
 extern int validate_change (rtx, rtx *, rtx, int);
 extern int insn_invalid_p (rtx);
+extern int verify_changes (int);
+extern void confirm_change_group (void);
 extern int apply_change_group (void);
 extern int num_validated_changes (void);
 extern void cancel_changes (int);

gcc/rtl.h

@@ -1912,6 +1912,7 @@ extern int rtx_renumbered_equal_p (rtx, rtx);
 extern int true_regnum (rtx);
 extern unsigned int reg_or_subregno (rtx);
 extern int redirect_jump_1 (rtx, rtx);
+extern void redirect_jump_2 (rtx, rtx, rtx, int, int);
 extern int redirect_jump (rtx, rtx, int);
 extern void rebuild_jump_labels (rtx);
 extern enum rtx_code reversed_comparison_code (rtx, rtx);