* function.c (thread_prologue_epilogue_insns): Don't move the

        line note at the head of the chain.  Only force a lineno note
        before the end of block 0.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@34207 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 74b7cb3..6dfc954 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,5 +1,11 @@
 2000-05-27  Richard Henderson  <rth@cygnus.com>
 
+       * function.c (thread_prologue_epilogue_insns): Don't move the
+       line note at the head of the chain.  Only force a lineno note
+       before the end of block 0.
+
+2000-05-27  Richard Henderson  <rth@cygnus.com>
+
        * gensupport.c (collect_insn_data): Record the maximum number
        of alternatives, not the last seen.
 

diff --git a/gcc/function.c b/gcc/function.c
index 63634bb..a59de4b 100644 (file)
--- a/gcc/function.c
+++ b/gcc/function.c
@@ -7038,10 +7038,11 @@ epilogue_done:
       rtx insn, prev;
 
       /* GDB handles `break f' by setting a breakpoint on the first
-        line note *after* the prologue.  Which means (1) that if
+        line note after the prologue.  Which means (1) that if
         there are line number notes before where we inserted the
-        prologue we should move them, and (2) if there is no such
-        note, then we should generate one at the prologue.  */
+        prologue we should move them, and (2) we should generate a
+        note before the end of the first basic block, if there isn't
+        one already there.  */
 
       for (insn = prologue_end; insn ; insn = prev)
        {
@@ -7050,32 +7051,34 @@ epilogue_done:
            {
              /* Note that we cannot reorder the first insn in the
                 chain, since rest_of_compilation relies on that
-                remaining constant.  Do the next best thing.  */
+                remaining constant.  */
              if (prev == NULL)
-               {
-                 emit_line_note_after (NOTE_SOURCE_FILE (insn),
-                                       NOTE_LINE_NUMBER (insn),
-                                       prologue_end);
-                 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
-               }
-             else
-               reorder_insns (insn, insn, prologue_end);
+               break;
+             reorder_insns (insn, insn, prologue_end);
            }
        }
 
-      insn = NEXT_INSN (prologue_end);
-      if (! insn || GET_CODE (insn) != NOTE || NOTE_LINE_NUMBER (insn) <= 0)
+      /* Find the last line number note in the first block.  */
+      for (insn = BASIC_BLOCK (0)->end;
+          insn != prologue_end;
+          insn = PREV_INSN (insn))
+       if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
+         break;
+
+      /* If we didn't find one, make a copy of the first line number
+        we run across.  */
+      if (! insn)
        {
-         for (insn = next_active_insn (f); insn ; insn = PREV_INSN (insn))
-           {
-             if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
-               {
-                 emit_line_note_after (NOTE_SOURCE_FILE (insn),
-                                       NOTE_LINE_NUMBER (insn),
-                                       prologue_end);
-                 break;
-               }
-           }
+         for (insn = next_active_insn (prologue_end);
+              insn;
+              insn = PREV_INSN (insn))
+           if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
+             {
+               emit_line_note_after (NOTE_SOURCE_FILE (insn),
+                                     NOTE_LINE_NUMBER (insn),
+                                     prologue_end);
+               break;
+             }
        }
     }
 #endif