diff options
Diffstat (limited to 'gcc/builtins.c')
| -rw-r--r-- | gcc/builtins.c | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/gcc/builtins.c b/gcc/builtins.c index 5b49b08..c940899 100644 --- a/gcc/builtins.c +++ b/gcc/builtins.c @@ -3990,10 +3990,32 @@ std_expand_builtin_va_arg (tree valist, tree type) tree align, alignm1; tree rounded_size; rtx addr; + HOST_WIDE_INT boundary; /* Compute the rounded size of the type. */ align = size_int (PARM_BOUNDARY / BITS_PER_UNIT); alignm1 = size_int (PARM_BOUNDARY / BITS_PER_UNIT - 1); + boundary = FUNCTION_ARG_BOUNDARY (TYPE_MODE (type), type); + + /* va_list pointer is aligned to PARM_BOUNDARY. If argument actually + requires greater alignment, we must perform dynamic alignment. */ + + if (boundary > PARM_BOUNDARY) + { + if (!PAD_VARARGS_DOWN) + { + t = build (MODIFY_EXPR, TREE_TYPE (valist), valist, + build (PLUS_EXPR, TREE_TYPE (valist), valist, + build_int_2 (boundary / BITS_PER_UNIT - 1, 0))); + TREE_SIDE_EFFECTS (t) = 1; + expand_expr (t, const0_rtx, VOIDmode, EXPAND_NORMAL); + } + t = build (MODIFY_EXPR, TREE_TYPE (valist), valist, + build (BIT_AND_EXPR, TREE_TYPE (valist), valist, + build_int_2 (~(boundary / BITS_PER_UNIT - 1), -1))); + TREE_SIDE_EFFECTS (t) = 1; + expand_expr (t, const0_rtx, VOIDmode, EXPAND_NORMAL); + } if (type == error_mark_node || (type_size = TYPE_SIZE_UNIT (TYPE_MAIN_VARIANT (type))) == NULL || TREE_OVERFLOW (type_size)) |