2013-11-27 Bernd Edlinger <bernd.edlinger@hotmail.de>

	reverted r205398 on request: Remove parameter keep_aligning from
	get_inner_reference.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@205452 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 30 insertions, 7 deletions

diff --git a/gcc/expr.c b/gcc/expr.c
index 8f8b5272846..4815c886f77 100644
--- a/gcc/expr.c
+++ b/gcc/expr.c
@@ -4657,7 +4657,7 @@ get_bit_range (unsigned HOST_WIDE_INT *bitstart,
       int unsignedp;
       int volatilep = 0;
       get_inner_reference (TREE_OPERAND (exp, 0), &rbitsize, &rbitpos,
-			   &roffset, &rmode, &unsignedp, &volatilep);
+			   &roffset, &rmode, &unsignedp, &volatilep, false);
       if ((rbitpos % BITS_PER_UNIT) != 0)
 	{
 	  *bitstart = *bitend = 0;
@@ -4810,7 +4810,7 @@ expand_assignment (tree to, tree from, bool nontemporal)
 
       push_temp_slots ();
       tem = get_inner_reference (to, &bitsize, &bitpos, &offset, &mode1,
-				 &unsignedp, &volatilep);
+				 &unsignedp, &volatilep, true);
 
       /* Make sure bitpos is not negative, it can wreak havoc later.  */
       if (bitpos < 0)
@@ -6652,13 +6652,27 @@ store_field (rtx target, HOST_WIDE_INT bitsize, HOST_WIDE_INT bitpos,
 
    If the field describes a variable-sized object, *PMODE is set to
    BLKmode and *PBITSIZE is set to -1.  An access cannot be made in
-   this case, but the address of the object can be found.  */
+   this case, but the address of the object can be found.
+
+   If KEEP_ALIGNING is true and the target is STRICT_ALIGNMENT, we don't
+   look through nodes that serve as markers of a greater alignment than
+   the one that can be deduced from the expression.  These nodes make it
+   possible for front-ends to prevent temporaries from being created by
+   the middle-end on alignment considerations.  For that purpose, the
+   normal operating mode at high-level is to always pass FALSE so that
+   the ultimate containing object is really returned; moreover, the
+   associated predicate handled_component_p will always return TRUE
+   on these nodes, thus indicating that they are essentially handled
+   by get_inner_reference.  TRUE should only be passed when the caller
+   is scanning the expression in order to build another representation
+   and specifically knows how to handle these nodes; as such, this is
+   the normal operating mode in the RTL expanders.  */
 
 tree
 get_inner_reference (tree exp, HOST_WIDE_INT *pbitsize,
 		     HOST_WIDE_INT *pbitpos, tree *poffset,
 		     enum machine_mode *pmode, int *punsignedp,
-		     int *pvolatilep)
+		     int *pvolatilep, bool keep_aligning)
 {
   tree size_tree = 0;
   enum machine_mode mode = VOIDmode;
@@ -6778,6 +6792,14 @@ get_inner_reference (tree exp, HOST_WIDE_INT *pbitsize,
 	  break;
 
 	case VIEW_CONVERT_EXPR:
+	  if (keep_aligning && STRICT_ALIGNMENT
+	      && (TYPE_ALIGN (TREE_TYPE (exp))
+	       > TYPE_ALIGN (TREE_TYPE (TREE_OPERAND (exp, 0))))
+	      && (TYPE_ALIGN (TREE_TYPE (TREE_OPERAND (exp, 0)))
+		  < BIGGEST_ALIGNMENT)
+	      && (TYPE_ALIGN_OK (TREE_TYPE (exp))
+		  || TYPE_ALIGN_OK (TREE_TYPE (TREE_OPERAND (exp, 0)))))
+	    goto done;
 	  break;
 
 	case MEM_REF:
@@ -7642,7 +7664,7 @@ expand_expr_addr_expr_1 (tree exp, rtx target, enum machine_mode tmode,
 	 they won't change the final object whose address will be returned
 	 (they actually exist only for that purpose).  */
       inner = get_inner_reference (exp, &bitsize, &bitpos, &offset,
-				   &mode1, &unsignedp, &volatilep);
+				   &mode1, &unsignedp, &volatilep, false);
       break;
     }
 
@@ -9919,7 +9941,7 @@ expand_expr_real_1 (tree exp, rtx target, enum machine_mode tmode,
 	tree offset;
 	int volatilep = 0, must_force_mem;
 	tree tem = get_inner_reference (exp, &bitsize, &bitpos, &offset,
-					&mode1, &unsignedp, &volatilep);
+					&mode1, &unsignedp, &volatilep, true);
 	rtx orig_op0, memloc;
 	bool mem_attrs_from_type = false;
 
@@ -10280,7 +10302,8 @@ expand_expr_real_1 (tree exp, rtx target, enum machine_mode tmode,
 	int volatilep = 0;
 	tree tem
 	  = get_inner_reference (treeop0, &bitsize, &bitpos,
-				 &offset, &mode1, &unsignedp, &volatilep);
+				 &offset, &mode1, &unsignedp, &volatilep,
+				 true);
 	rtx orig_op0;
 
 	/* ??? We should work harder and deal with non-zero offsets.  */