2012-10-18 Basile Starynkevitch <basile@starynkevitch.net>

	MELT branch merged with trunk rev 192552 using svnmerge.py



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/branches/melt-branch@192557 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 33 insertions, 10 deletions

diff --git a/gcc/dse.c b/gcc/dse.c
index eff4a3909c8..631a1f20ac7 100644
--- a/gcc/dse.c
+++ b/gcc/dse.c
@@ -989,7 +989,32 @@ delete_dead_store_insn (insn_info_t insn_info)
   insn_info->wild_read = false;
 }
 
-/* Check if EXPR can possibly escape the current function scope.  */
+/* Return whether DECL, a local variable, can possibly escape the current
+   function scope.  */
+
+static bool
+local_variable_can_escape (tree decl)
+{
+  if (TREE_ADDRESSABLE (decl))
+    return true;
+
+  /* If this is a partitioned variable, we need to consider all the variables
+     in the partition.  This is necessary because a store into one of them can
+     be replaced with a store into another and this may not change the outcome
+     of the escape analysis.  */
+  if (cfun->gimple_df->decls_to_pointers != NULL)
+    {
+      void *namep
+	= pointer_map_contains (cfun->gimple_df->decls_to_pointers, decl);
+      if (namep)
+	return TREE_ADDRESSABLE (*(tree *)namep);
+    }
+
+  return false;
+}
+
+/* Return whether EXPR can possibly escape the current function scope.  */
+
 static bool
 can_escape (tree expr)
 {
@@ -998,7 +1023,11 @@ can_escape (tree expr)
     return true;
   base = get_base_address (expr);
   if (DECL_P (base)
-      && !may_be_aliased (base))
+      && !may_be_aliased (base)
+      && !(TREE_CODE (base) == VAR_DECL
+	   && !DECL_EXTERNAL (base)
+	   && !TREE_STATIC (base)
+	   && local_variable_can_escape (base)))
     return false;
   return true;
 }
@@ -2518,14 +2547,8 @@ scan_insn (bb_info_t bb_info, rtx insn)
       const_call = RTL_CONST_CALL_P (insn);
       if (!const_call)
 	{
-	  rtx call = PATTERN (insn);
-	  if (GET_CODE (call) == PARALLEL)
-	    call = XVECEXP (call, 0, 0);
-	  if (GET_CODE (call) == SET)
-	    call = SET_SRC (call);
-	  if (GET_CODE (call) == CALL
-	      && MEM_P (XEXP (call, 0))
-	      && GET_CODE (XEXP (XEXP (call, 0), 0)) == SYMBOL_REF)
+	  rtx call = get_call_rtx_from (insn);
+	  if (call && GET_CODE (XEXP (XEXP (call, 0), 0)) == SYMBOL_REF)
 	    {
 	      rtx symbol = XEXP (XEXP (call, 0), 0);
 	      if (SYMBOL_REF_DECL (symbol)