2006-01-16 Gabor Loki <loki@gcc.gnu.org>

	* rtl-factoring.c : Add sequence abstraction algorithm.
	* cfgcleanup.c (outgoing_edges_match): Extra checks.
	(try_crossjump_to_edge): Avoid deleting preserve label when redirecting
	ABNORMAL edges.
	(block_has_preserve_label): New function.
	* common.opt: Register new pass.
	* Makefile.in: Ditto.
	* passes.c: Ditto.
	* timevar.def: Ditto.
	* tree-pass.h: Ditto.
	* emit-rtl.c (make_jump_insn_raw): Remove forward decl.
	* rtl.h (make_jump_insn_raw): Add forward decl.
	* doc/invoke.texi: Add documentation for
																	                  -frtl-abstract-sequences.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@109750 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 39 insertions, 2 deletions

diff --git a/gcc/cfgcleanup.c b/gcc/cfgcleanup.c
index 8bc49a2abd8..4f0c9d4de8a 100644
--- a/gcc/cfgcleanup.c
+++ b/gcc/cfgcleanup.c
@@ -1589,11 +1589,43 @@ outgoing_edges_match (int mode, basic_block bb1, basic_block bb2)
       return false;
   }
 
-  /* We don't need to match the rest of edges as above checks should be enough
-     to ensure that they are equivalent.  */
+  /* The same checks as in try_crossjump_to_edge. It is required for RTL
+     version of sequence abstraction.  */
+  FOR_EACH_EDGE (e1, ei, bb2->succs)
+    {
+      edge e2;
+      edge_iterator ei;
+      basic_block d1 = e1->dest;
+
+      if (FORWARDER_BLOCK_P (d1))
+        d1 = EDGE_SUCC (d1, 0)->dest;
+
+      FOR_EACH_EDGE (e2, ei, bb1->succs)
+        {
+          basic_block d2 = e2->dest;
+          if (FORWARDER_BLOCK_P (d2))
+            d2 = EDGE_SUCC (d2, 0)->dest;
+          if (d1 == d2)
+            break;
+        }
+
+      if (!e2)
+        return false;
+    }
+
   return true;
 }
 
+/* Returns true if BB basic block has a preserve label.  */
+
+static bool
+block_has_preserve_label (basic_block bb)
+{
+  return (bb
+          && block_label (bb)
+          && LABEL_PRESERVE_P (block_label (bb)));
+}
+
 /* E1 and E2 are edges with the same destination block.  Search their
    predecessors for common code.  If found, redirect control flow from
    (maybe the middle of) E1->SRC to (maybe the middle of) E2->SRC.  */
@@ -1669,6 +1701,11 @@ try_crossjump_to_edge (int mode, edge e1, edge e2)
       && (newpos1 != BB_HEAD (src1)))
     return false;
 
+  /* Avoid deleting preseve label when redirecting ABNORMAL edeges.  */
+  if (block_has_preserve_label (e1->dest)
+      && (e1->flags & EDGE_ABNORMAL))
+    return false;
+
   /* Here we know that the insns in the end of SRC1 which are common with SRC2
      will be deleted.
      If we have tablejumps in the end of SRC1 and SRC2