final.c (shorten_branches): Tag the loop alignment onto the first label after NOTE_IN...

	* final.c (shorten_branches): Tag the loop alignment onto the
	first label after NOTE_INSN_LOOP_BEG even if there is an
	intervening insn.

From-SVN: r18396

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 454f439d337096d2fd1abcab486963a5cafa110d..52f74dbd6ccc177a03fe68bcdcbbe19bdd3c60a7 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+Wed Mar  4 15:51:19 1998  J"orn Rennecke <amylaar@cygnus.co.uk>
+
+       * final.c (shorten_branches): Tag the loop alignment onto the
+       first label after NOTE_INSN_LOOP_BEG even if there is an
+       intervening insn.
+
 Tue Mar  3 21:48:35 1998  J"orn Rennecke <amylaar@cygnus.co.uk>
 
        * final.c (insn_current_reference_address):

diff --git a/gcc/final.c b/gcc/final.c
index 35628f6419d2176ef7c7599054c66abec01e4731..9fb40ac871ed848db436bb086986de95ecc944c0 100644 (file)
--- a/gcc/final.c
+++ b/gcc/final.c
@@ -982,13 +982,23 @@ shorten_branches (first)
 
   /* Initialize label_align and set up uid_shuid to be strictly
      monotonically rising with insn order.  */
+  /* We use max_log here to keep track of the maximum alignment we want to
+     impose on the next CODE_LABEL (or the current one if we are processing
+     the CODE_LABEL itself).  */
+     
   for (max_log = 0, insn = get_insns (), i = 1; insn; insn = NEXT_INSN (insn))
     {
       int log;
 
       INSN_SHUID (insn) = i++;
       if (GET_RTX_CLASS (GET_CODE (insn)) == 'i')
-       max_log = 0;
+       {
+         /* reorg might make the first insn of a loop being run once only,
+             and delete the label in front of it.  Then we want to apply
+             the loop alignment to the new label created by reorg, which
+             is separated by the former loop start insn from the
+            NOTE_INSN_LOOP_BEG.  */
+       }
       else if (GET_CODE (insn) == CODE_LABEL)
        {
          rtx next;
@@ -1028,13 +1038,14 @@ shorten_branches (first)
                break;
              }
        }
+      /* Again, we allow NOTE_INSN_LOOP_BEG - INSN - CODE_LABEL
+        sequences in order to handle reorg output efficiently.  */
       else if (GET_CODE (insn) == NOTE
               && NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_BEG)
        {
          rtx label;
 
-         for (label = insn; label && GET_RTX_CLASS (GET_CODE (label)) != 'i';
-              label = NEXT_INSN (label))
+         for (label = insn; label; label = NEXT_INSN (label))
            if (GET_CODE (label) == CODE_LABEL)
              {
                log = LOOP_ALIGN (insn);