diff options
Diffstat (limited to 'gcc-4.6/gcc/ada/gcc-interface/decl.c')
| -rw-r--r-- | gcc-4.6/gcc/ada/gcc-interface/decl.c | 25 |
1 files changed, 20 insertions, 5 deletions
diff --git a/gcc-4.6/gcc/ada/gcc-interface/decl.c b/gcc-4.6/gcc/ada/gcc-interface/decl.c index e576895..58459d4 100644 --- a/gcc-4.6/gcc/ada/gcc-interface/decl.c +++ b/gcc-4.6/gcc/ada/gcc-interface/decl.c @@ -808,16 +808,30 @@ gnat_to_gnu_entity (Entity_Id gnat_entity, tree gnu_expr, int definition) && No (Address_Clause (gnat_entity)))) && TREE_CODE (TYPE_SIZE (gnu_type)) == INTEGER_CST) { - /* No point in jumping through all the hoops needed in order + unsigned int size_cap, align_cap; + + /* No point in promoting the alignment if this doesn't prevent + BLKmode access to the object, in particular block copy, as + this will for example disable the NRV optimization for it. + No point in jumping through all the hoops needed in order to support BIGGEST_ALIGNMENT if we don't really have to. So we cap to the smallest alignment that corresponds to a known efficient memory access pattern of the target. */ - unsigned int align_cap = Is_Atomic (gnat_entity) - ? BIGGEST_ALIGNMENT - : get_mode_alignment (ptr_mode); + if (Is_Atomic (gnat_entity)) + { + size_cap = UINT_MAX; + align_cap = BIGGEST_ALIGNMENT; + } + else + { + size_cap = MAX_FIXED_MODE_SIZE; + align_cap = get_mode_alignment (ptr_mode); + } if (!host_integerp (TYPE_SIZE (gnu_type), 1) - || compare_tree_int (TYPE_SIZE (gnu_type), align_cap) >= 0) + || compare_tree_int (TYPE_SIZE (gnu_type), size_cap) > 0) + align = 0; + else if (compare_tree_int (TYPE_SIZE (gnu_type), align_cap) > 0) align = align_cap; else align = ceil_alignment (tree_low_cst (TYPE_SIZE (gnu_type), 1)); @@ -6422,6 +6436,7 @@ maybe_pad_type (tree type, tree size, unsigned int align, if (align != 0 && TREE_CODE (type) == RECORD_TYPE && TYPE_MODE (type) == BLKmode + && !TREE_ADDRESSABLE (type) && TREE_CODE (orig_size) == INTEGER_CST && !TREE_OVERFLOW (orig_size) && compare_tree_int (orig_size, MAX_FIXED_MODE_SIZE) <= 0 |