PR target/45815

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

diff --git a/gcc/cfgcleanup.c b/gcc/cfgcleanup.c
index 9f3e68e..d28ae6f 100644 (file)
--- a/gcc/cfgcleanup.c
+++ b/gcc/cfgcleanup.c
@@ -1944,7 +1944,7 @@ try_head_merge_bb (basic_block bb)
   basic_block final_dest_bb = NULL;
   int max_match = INT_MAX;
   edge e0;
-  rtx *headptr, *currptr;
+  rtx *headptr, *currptr, *nextptr;
   bool changed, moveall;
   unsigned ix;
   rtx e0_last_head, cond, move_before;
@@ -2077,6 +2077,7 @@ try_head_merge_bb (basic_block bb)
 
   currptr = XNEWVEC (rtx, nedges);
   headptr = XNEWVEC (rtx, nedges);
+  nextptr = XNEWVEC (rtx, nedges);
 
   for (ix = 0; ix < nedges; ix++)
     {
@@ -2132,6 +2133,14 @@ try_head_merge_bb (basic_block bb)
 
          /* Try again, using a different insertion point.  */
          move_before = jump;
+
+#ifdef HAVE_cc0
+         /* Don't try moving before a cc0 user, as that may invalidate
+            the cc0.  */
+         if (reg_mentioned_p (cc0_rtx, jump))
+           break;
+#endif
+
          continue;
        }
 
@@ -2155,6 +2164,18 @@ try_head_merge_bb (basic_block bb)
            }
        }
 
+      /* If we can't currently move all of the identical insns, remember
+        each insn after the range that we'll merge.  */
+      if (!moveall)
+       for (ix = 0; ix < nedges; ix++)
+         {
+           rtx curr = currptr[ix];
+           do
+             curr = NEXT_INSN (curr);
+           while (!NONDEBUG_INSN_P (curr));
+           nextptr[ix] = curr;
+         }
+
       reorder_insns (headptr[0], currptr[0], PREV_INSN (move_before));
       df_set_bb_dirty (EDGE_SUCC (bb, 0)->dest);
       if (final_dest_bb != NULL)
@@ -2170,16 +2191,18 @@ try_head_merge_bb (basic_block bb)
          if (jump == move_before)
            break;
 
-         /* Try again, using a different insertion point.  */
+         /* For the unmerged insns, try a different insertion point.  */
          move_before = jump;
+
+#ifdef HAVE_cc0
+         /* Don't try moving before a cc0 user, as that may invalidate
+            the cc0.  */
+         if (reg_mentioned_p (cc0_rtx, jump))
+           break;
+#endif
+
          for (ix = 0; ix < nedges; ix++)
-           {
-             rtx curr = currptr[ix];
-             do
-               curr = NEXT_INSN (curr);
-             while (!NONDEBUG_INSN_P (curr));
-             currptr[ix] = headptr[ix] = curr;
-           }
+           currptr[ix] = headptr[ix] = nextptr[ix];
        }
     }
   while (!moveall);
@@ -2187,6 +2210,7 @@ try_head_merge_bb (basic_block bb)
  out:
   free (currptr);
   free (headptr);
+  free (nextptr);
 
   crossjumps_occured |= changed;