2005-06-07 Jerry DeLisle <jvdelisle@verizon.net>

[pf3gnuchains/gcc-fork.git] / gcc / recog.c

diff --git a/gcc/recog.c b/gcc/recog.c
index 28b2410..836ebb3 100644 (file)
--- a/gcc/recog.c
+++ b/gcc/recog.c
@@ -235,6 +235,46 @@ validate_change (rtx object, rtx *loc, rtx new, int in_group)
     return apply_change_group ();
 }
 
+
+/* Function to be passed to for_each_rtx to test whether a piece of
+   RTL contains any mem/v.  */
+static int
+volatile_mem_p (rtx *x, void *data ATTRIBUTE_UNUSED)
+{
+  return (MEM_P (*x) && MEM_VOLATILE_P (*x));
+}
+
+/* Same as validate_change, but doesn't support groups, and it accepts
+   volatile mems if they're already present in the original insn.  */
+
+int
+validate_change_maybe_volatile (rtx object, rtx *loc, rtx new)
+{
+  int result;
+
+  if (validate_change (object, loc, new, 0))
+    return 1;
+
+  if (volatile_ok
+      /* If there isn't a volatile MEM, there's nothing we can do.  */
+      || !for_each_rtx (&PATTERN (object), volatile_mem_p, 0)
+      /* Make sure we're not adding or removing volatile MEMs.  */
+      || for_each_rtx (loc, volatile_mem_p, 0)
+      || for_each_rtx (&new, volatile_mem_p, 0)
+      || !insn_invalid_p (object))
+    return 0;
+
+  volatile_ok = 1;
+
+  gcc_assert (!insn_invalid_p (object));
+
+  result = validate_change (object, loc, new, 0);
+
+  volatile_ok = 0;
+
+  return result;
+}
+
 /* This subroutine of apply_change_group verifies whether the changes to INSN
    were valid; i.e. whether INSN can still be recognized.  */
 
@@ -294,11 +334,11 @@ 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)
+static int
+verify_changes (int num)
 {
   int i;
   rtx last_validated = NULL_RTX;
@@ -312,7 +352,7 @@ 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 +416,38 @@ 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 +457,7 @@ apply_change_group (void)
     }
 }
 
+
 /* Return the number of changes so far in the current group.  */
 
 int
@@ -3070,7 +3132,6 @@ peephole2_optimize (FILE *dump_file ATTRIBUTE_UNUSED)
                          {
                          case REG_NORETURN:
                          case REG_SETJMP:
-                         case REG_ALWAYS_RETURN:
                            REG_NOTES (new_insn)
                              = gen_rtx_EXPR_LIST (REG_NOTE_KIND (note),
                                                   XEXP (note, 0),