* trans-array.c (gfc_trans_array_bound_check,

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

diff --git a/gcc/cfgcleanup.c b/gcc/cfgcleanup.c
index f413791..b59cf7b 100644 (file)
--- a/gcc/cfgcleanup.c
+++ b/gcc/cfgcleanup.c
@@ -895,13 +895,15 @@ merge_memattrs (rtx x, rtx y)
            {
              set_mem_expr (x, 0);
              set_mem_expr (y, 0);
-             set_mem_offset (x, 0);
-             set_mem_offset (y, 0);
+             clear_mem_offset (x);
+             clear_mem_offset (y);
            }
-         else if (MEM_OFFSET (x) != MEM_OFFSET (y))
+         else if (MEM_OFFSET_KNOWN_P (x) != MEM_OFFSET_KNOWN_P (y)
+                  || (MEM_OFFSET_KNOWN_P (x)
+                      && MEM_OFFSET (x) != MEM_OFFSET (y)))
            {
-             set_mem_offset (x, 0);
-             set_mem_offset (y, 0);
+             clear_mem_offset (x);
+             clear_mem_offset (y);
            }
 
          if (MEM_SIZE_KNOWN_P (x) && MEM_SIZE_KNOWN_P (y))
@@ -1076,6 +1078,25 @@ old_insns_match_p (int mode ATTRIBUTE_UNUSED, rtx i1, rtx i2)
   if (NOTE_INSN_BASIC_BLOCK_P (i1) && NOTE_INSN_BASIC_BLOCK_P (i2))
     return dir_both;
 
+  /* ??? Do not allow cross-jumping between different stack levels.  */
+  p1 = find_reg_note (i1, REG_ARGS_SIZE, NULL);
+  p2 = find_reg_note (i2, REG_ARGS_SIZE, NULL);
+  if (p1 && p2)
+    {
+      p1 = XEXP (p1, 0);
+      p2 = XEXP (p2, 0);
+      if (!rtx_equal_p (p1, p2))
+        return dir_none;
+
+      /* ??? Worse, this adjustment had better be constant lest we
+         have differing incoming stack levels.  */
+      if (!frame_pointer_needed
+          && find_args_size_adjust (i1) == HOST_WIDE_INT_MIN)
+       return dir_none;
+    }
+  else if (p1 || p2)
+    return dir_none;
+
   p1 = PATTERN (i1);
   p2 = PATTERN (i2);
 
@@ -1467,6 +1488,16 @@ outgoing_edges_match (int mode, basic_block bb1, basic_block bb2)
   edge e1, e2;
   edge_iterator ei;
 
+  /* If we performed shrink-wrapping, edges to the EXIT_BLOCK_PTR can
+     only be distinguished for JUMP_INSNs.  The two paths may differ in
+     whether they went through the prologue.  Sibcalls are fine, we know
+     that we either didn't need or inserted an epilogue before them.  */
+  if (crtl->shrink_wrapped
+      && single_succ_p (bb1) && single_succ (bb1) == EXIT_BLOCK_PTR
+      && !JUMP_P (BB_END (bb1))
+      && !(CALL_P (BB_END (bb1)) && SIBLING_CALL_P (BB_END (bb1))))
+    return false;
+  
   /* If BB1 has only one successor, we may be looking at either an
      unconditional jump, or a fake edge to exit.  */
   if (single_succ_p (bb1)
@@ -2193,7 +2224,14 @@ try_head_merge_bb (basic_block bb)
 
   cond = get_condition (jump, &move_before, true, false);
   if (cond == NULL_RTX)
-    move_before = jump;
+    {
+#ifdef HAVE_cc0
+      if (reg_mentioned_p (cc0_rtx, jump))
+       move_before = prev_nonnote_nondebug_insn (jump);
+      else
+#endif
+       move_before = jump;
+    }
 
   for (ix = 0; ix < nedges; ix++)
     if (EDGE_SUCC (bb, ix)->dest == EXIT_BLOCK_PTR)
@@ -2355,7 +2393,14 @@ try_head_merge_bb (basic_block bb)
       jump = BB_END (final_dest_bb);
       cond = get_condition (jump, &move_before, true, false);
       if (cond == NULL_RTX)
-       move_before = jump;
+       {
+#ifdef HAVE_cc0
+         if (reg_mentioned_p (cc0_rtx, jump))
+           move_before = prev_nonnote_nondebug_insn (jump);
+         else
+#endif
+           move_before = jump;
+       }
     }
 
   do