Use is_empty_type instead of zero-sized type.

Instead of only removing assignments of zero-sized types,
assignments of all empty types should be removed during gimplification.
This moves to use is_empty_type which will be used in other places too.

OK?  Bootstrapped and tested on aarch64-linux-gnu with no regressions.

Thanks,
Andrew Pinski

gcc/ChangeLog:

	* gimplify.c (zero_sized_field_decl): Delete
	(zero_sized_type): Delete
	(gimplify_init_ctor_eval): Use is_empty_type instead
	of zero_sized_field_decl.
	(gimplify_modify_expr): Use is_empty_type instead of
	zero_sized_type.
This commit is contained in:
Andrew Pinski 2021-05-31 12:25:28 +00:00
parent 833d348aec
commit 34aae6b561
1 changed files with 7 additions and 27 deletions

View File

@ -4644,28 +4644,6 @@ gimplify_init_ctor_eval_range (tree object, tree lower, tree upper,
gimplify_seq_add_stmt (pre_p, gimple_build_label (loop_exit_label));
}
/* Return true if FDECL is accessing a field that is zero sized. */
static bool
zero_sized_field_decl (const_tree fdecl)
{
if (TREE_CODE (fdecl) == FIELD_DECL && DECL_SIZE (fdecl)
&& integer_zerop (DECL_SIZE (fdecl)))
return true;
return false;
}
/* Return true if TYPE is zero sized. */
static bool
zero_sized_type (const_tree type)
{
if (AGGREGATE_TYPE_P (type) && TYPE_SIZE (type)
&& integer_zerop (TYPE_SIZE (type)))
return true;
return false;
}
/* A subroutine of gimplify_init_constructor. Generate individual
MODIFY_EXPRs for a CONSTRUCTOR. OBJECT is the LHS against which the
assignments should happen. ELTS is the CONSTRUCTOR_ELTS of the
@ -4699,11 +4677,13 @@ gimplify_init_ctor_eval (tree object, vec<constructor_elt, va_gc> *elts,
gcc_assert (purpose);
/* Skip zero-sized fields, unless value has side-effects. This can
happen with calls to functions returning a zero-sized type, which
happen with calls to functions returning a empty type, which
we shouldn't discard. As a number of downstream passes don't
expect sets of zero-sized fields, we rely on the gimplification of
expect sets of empty type fields, we rely on the gimplification of
the MODIFY_EXPR we make below to drop the assignment statement. */
if (! TREE_SIDE_EFFECTS (value) && zero_sized_field_decl (purpose))
if (!TREE_SIDE_EFFECTS (value)
&& TREE_CODE (purpose) == FIELD_DECL
&& is_empty_type (TREE_TYPE (purpose)))
continue;
/* If we have a RANGE_EXPR, we have to build a loop to assign the
@ -5781,11 +5761,11 @@ gimplify_modify_expr (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p,
if (ret != GS_UNHANDLED)
return ret;
/* For zero sized types only gimplify the left hand side and right hand
/* For empty types only gimplify the left hand side and right hand
side as statements and throw away the assignment. Do this after
gimplify_modify_expr_rhs so we handle TARGET_EXPRs of addressable
types properly. */
if (zero_sized_type (TREE_TYPE (*from_p))
if (is_empty_type (TREE_TYPE (*from_p))
&& !want_value
/* Don't do this for calls that return addressable types, expand_call
relies on those having a lhs. */