re PR rtl-optimization/23392 (foward-1.m fails with -funroll-loops -O3 -fgnu-runtime)

	PR rtl-optimization/23392
	* regrename.c (enum scan_actions) Add mark_access.
	(scan_actions_name): Ditto.
	(scan_rtx_reg): Handle mark_access.
	(scan_rtx_address): Do nothing for mark_access.
	(build_def_use): Mark source registers in REG_FRAME_RELATED_EXPR
	and regs in REG_INC notes before closing chains for dead regs.
	Mark destination regs in REG_FRAME_RELATED_EXPR notes after
	opening chains for new writes.

From-SVN: r107059

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 48f8948..1ffb83f 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,15 @@
+2005-11-16  Alan Modra  <amodra@bigpond.net.au>
+
+       PR rtl-optimization/23392
+       * regrename.c (enum scan_actions) Add mark_access.
+       (scan_actions_name): Ditto.
+       (scan_rtx_reg): Handle mark_access.
+       (scan_rtx_address): Do nothing for mark_access.
+       (build_def_use): Mark source registers in REG_FRAME_RELATED_EXPR
+       and regs in REG_INC notes before closing chains for dead regs.
+       Mark destination regs in REG_FRAME_RELATED_EXPR notes after
+       opening chains for new writes.
+
 2005-11-15  David Edelsohn  <edelsohn@gnu.org>
 
        * c.opt (ffixed-line-length-none): New.

diff --git a/gcc/regrename.c b/gcc/regrename.c
index cd448c4..06b1c5b 100644 (file)
--- a/gcc/regrename.c
+++ b/gcc/regrename.c
@@ -58,7 +58,11 @@ enum scan_actions
   terminate_write,
   terminate_dead,
   mark_read,
-  mark_write
+  mark_write,
+  /* mark_access is for marking the destination regs in
+     REG_FRAME_RELATED_EXPR notes (as if they were read) so that the
+     note is updated properly.  */
+  mark_access
 };
 
 static const char * const scan_actions_name[] =
@@ -68,7 +72,8 @@ static const char * const scan_actions_name[] =
   "terminate_write",
   "terminate_dead",
   "mark_read",
-  "mark_write"
+  "mark_write",
+  "mark_access"
 };
 
 static struct obstack rename_obstack;
@@ -408,8 +413,7 @@ scan_rtx_reg (rtx insn, rtx *loc, enum reg_class cl,
       return;
     }
 
-  if ((type == OP_OUT && action != terminate_write)
-      || (type != OP_OUT && action == terminate_write))
+  if ((type == OP_OUT) != (action == terminate_write || action == mark_access))
     return;
 
   for (p = &open_chains; *p;)
@@ -438,7 +442,7 @@ scan_rtx_reg (rtx insn, rtx *loc, enum reg_class cl,
              continue;
            }
 
-         if (action == mark_read)
+         if (action == mark_read || action == mark_access)
            {
              gcc_assert (exact_match);
 
@@ -509,7 +513,7 @@ scan_rtx_address (rtx insn, rtx *loc, enum reg_class cl,
   const char *fmt;
   int i, j;
 
-  if (action == mark_write)
+  if (action == mark_write || action == mark_access)
     return;
 
   switch (code)
@@ -866,17 +870,19 @@ build_def_use (basic_block bb)
                scan_rtx (insn, loc, cl, mark_read, type, 0);
            }
 
-         /* Step 4: Close chains for registers that die here.
-            Also record updates for REG_INC notes.  */
+         /* Step 3B: Record updates for regs in REG_INC notes, and
+            source regs in REG_FRAME_RELATED_EXPR notes.  */
          for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
-           {
-             if (REG_NOTE_KIND (note) == REG_DEAD)
-               scan_rtx (insn, &XEXP (note, 0), NO_REGS, terminate_dead,
-                         OP_IN, 0);
-             else if (REG_NOTE_KIND (note) == REG_INC)
-               scan_rtx (insn, &XEXP (note, 0), ALL_REGS, mark_read,
-                         OP_INOUT, 0);
-           }
+           if (REG_NOTE_KIND (note) == REG_INC
+               || REG_NOTE_KIND (note) == REG_FRAME_RELATED_EXPR)
+             scan_rtx (insn, &XEXP (note, 0), ALL_REGS, mark_read,
+                       OP_INOUT, 0);
+
+         /* Step 4: Close chains for registers that die here.  */
+         for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
+           if (REG_NOTE_KIND (note) == REG_DEAD)
+             scan_rtx (insn, &XEXP (note, 0), NO_REGS, terminate_dead,
+                       OP_IN, 0);
 
          /* Step 4B: If this is a call, any chain live at this point
             requires a caller-saved reg.  */
@@ -949,6 +955,13 @@ build_def_use (basic_block bb)
                            recog_op_alt[opn][alt].earlyclobber);
              }
 
+         /* Step 6B: Record destination regs in REG_FRAME_RELATED_EXPR
+            notes for update.  */
+         for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
+           if (REG_NOTE_KIND (note) == REG_FRAME_RELATED_EXPR)
+             scan_rtx (insn, &XEXP (note, 0), ALL_REGS, mark_access,
+                       OP_INOUT, 0);
+
          /* Step 7: Close chains for registers that were never
             really used here.  */
          for (note = REG_NOTES (insn); note; note = XEXP (note, 1))