gcc: another round of merges from the gcc pre-43 branch.

Bring The following revisions from the gcc43 branch[1]:

118360, 118361, 118363, 118576, 119820,
123906, 125246, and 125721.

They all have in common that the were merged long ago
into Apple's gcc and should help improve the general
quality of the compiler and make it easier to bring
new features from Apple's gcc42.

For details please review the additions to the files:
gcc/ChangeLog.gcc43
gcc/cp/ChangeLog.gcc43 (new, adds previous revisions)

Reference:
[1] http://gcc.gnu.org/viewcvs/gcc/trunk/?pathrev=126700

Obtained from:	gcc pre4.3 (GPLv2) branch
MFC after:	3 weeks

1 files changed, 19 insertions, 3 deletions

diff --git a/contrib/gcc/tree-ssa-propagate.c b/contrib/gcc/tree-ssa-propagate.c
index e085911..1a8a614 100644
--- a/contrib/gcc/tree-ssa-propagate.c
+++ b/contrib/gcc/tree-ssa-propagate.c
@@ -1,5 +1,5 @@
 /* Generic SSA value propagation engine.
-   Copyright (C) 2004, 2005, 2006 Free Software Foundation, Inc.
+   Copyright (C) 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
    Contributed by Diego Novillo <dnovillo@redhat.com>
 
    This file is part of GCC.
@@ -176,6 +176,8 @@ cfg_blocks_empty_p (void)
 static void 
 cfg_blocks_add (basic_block bb)
 {
+  bool head = false;
+
   gcc_assert (bb != ENTRY_BLOCK_PTR && bb != EXIT_BLOCK_PTR);
   gcc_assert (!TEST_BIT (bb_in_list, bb->index));
 
@@ -198,12 +200,26 @@ cfg_blocks_add (basic_block bb)
 	  cfg_blocks_head = 0;
 	  VEC_safe_grow (basic_block, heap, cfg_blocks, 2 * cfg_blocks_tail);
 	}
-      else
+      /* Minor optimization: we prefer to see blocks with more
+	 predecessors later, because there is more of a chance that
+	 the incoming edges will be executable.  */
+      else if (EDGE_COUNT (bb->preds)
+	       >= EDGE_COUNT (VEC_index (basic_block, cfg_blocks,
+					 cfg_blocks_head)->preds))
 	cfg_blocks_tail = ((cfg_blocks_tail + 1)
 			   % VEC_length (basic_block, cfg_blocks));
+      else
+	{
+	  if (cfg_blocks_head == 0)
+	    cfg_blocks_head = VEC_length (basic_block, cfg_blocks);
+	  --cfg_blocks_head;
+	  head = true;
+	}
     }
 
-  VEC_replace (basic_block, cfg_blocks, cfg_blocks_tail, bb);
+  VEC_replace (basic_block, cfg_blocks,
+	       head ? cfg_blocks_head : cfg_blocks_tail,
+	       bb);
   SET_BIT (bb_in_list, bb->index);
 }