(reposition_prologue_and_epilogue_notes): Search for the notes without using...

(reposition_prologue_and_epilogue_notes): Search for the notes without
using basic_block_end[0] or basic_block_head[N-1].

From-SVN: r1735

diff --git a/gcc/function.c b/gcc/function.c
index 4fa8ed019a0d9d749de93d1b1ccc8bad4dd4b7a7..92502eb9369395c4fd4a10938a0d6992c756cacb 100644 (file)
--- a/gcc/function.c
+++ b/gcc/function.c
@@ -4379,58 +4379,74 @@ reposition_prologue_and_epilogue_notes (f)
   if (n_basic_blocks)
     {
       rtx next, prev;
+      int len;
 
       if (prologue)
        {
-         register rtx insn, end_prologue;
-
-         /* From the end of the first basic block, search backward for a
-            prologue insn.  */
-         for (insn = NEXT_INSN (PREV_INSN (basic_block_end[0]));
-              insn; insn = prev_nonnote_insn (insn))
-           if (contains (insn, prologue))
+         register rtx insn, note = 0;
+
+         /* Scan from the beginning until we reach the last prologue insn.
+            We apparently can't depend on basic_block_{head,end} after
+            reorg has run.  */
+         for (len = 0; prologue[len]; len++)
+           ;
+         for (insn = f; insn; insn = NEXT_INSN (insn))
+           if (GET_CODE (insn) == NOTE)
+             {
+               if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
+                 note = insn;
+             }
+           else if (contains (insn, prologue) && --len == 0)
              {
-               end_prologue = insn;
-               /* Find the prologue-end note and move it to just after the
-                  last prologue insn.  */
-               for (insn = f; insn; insn = NEXT_INSN (insn))
-                 if (GET_CODE (insn) == NOTE
-                     && NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
-                   break;
-               next = NEXT_INSN (insn);
-               prev = PREV_INSN (insn);
+               /* Find the prologue-end note if we haven't already, and
+                  move it to just after the last prologue insn.  */
+               if (note == 0)
+                 for (note = insn; note = NEXT_INSN (note);)
+                   if (GET_CODE (note) == NOTE
+                       && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
+                     break;
+               next = NEXT_INSN (note);
+               prev = PREV_INSN (note);
                if (prev)
                  NEXT_INSN (prev) = next;
                if (next)
                  PREV_INSN (next) = prev;
-               add_insn_after (insn, end_prologue);
+               add_insn_after (note, insn);
                break;
              }
        }
 
       if (epilogue)
        {
-         register rtx insn, beg_epilogue;
-
-         /* From the start of the last basic block, search forward for an
-            epilogue insn.  */
-         for (insn = PREV_INSN (NEXT_INSN (basic_block_head[n_basic_blocks - 1]));
-              insn; insn = next_nonnote_insn (insn))
-           if (beg_epilogue = contains (insn, epilogue))
+         register rtx insn, note = 0;
+
+         /* Scan from the end until we reach the first epilogue insn.
+            We apparently can't depend on basic_block_{head,end} after
+            reorg has run.  */
+         for (len = 0; epilogue[len]; len++)
+           ;
+         for (insn = get_last_insn (); insn; insn = PREV_INSN (insn))
+           if (GET_CODE (insn) == NOTE)
+             {
+               if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
+                 note = insn;
+             }
+           else if (contains (insn, epilogue) && --len == 0)
              {
-               /* Find the epilogue-begin note and move it to just before
-                  the first epilogue insn.  */
-               for (insn = get_last_insn (); insn; insn = PREV_INSN (insn))
-                 if (GET_CODE (insn) == NOTE
-                     && NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
-                   break;
-               next = NEXT_INSN (insn);
-               prev = PREV_INSN (insn);
+               /* Find the epilogue-begin note if we haven't already, and
+                  move it to just before the first epilogue insn.  */
+               if (note == 0)
+                 for (note = insn; note = PREV_INSN (note);)
+                   if (GET_CODE (note) == NOTE
+                       && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
+                     break;
+               next = NEXT_INSN (note);
+               prev = PREV_INSN (note);
                if (prev)
                  NEXT_INSN (prev) = next;
                if (next)
                  PREV_INSN (next) = prev;
-               add_insn_after (insn, PREV_INSN (beg_epilogue));
+               add_insn_after (note, PREV_INSN (insn));
                break;
              }
        }