tree.h (struct record_layout_info_s): New field unpadded_align.

* tree.h (struct record_layout_info_s): New field unpadded_align.
	(set_lang_adjust_rli): New declaration.
	* stor-layout.c (layout_decl): If DECL is packed, but at alignment
	it would have if not packed, do not downgrade DECL_ALIGN.
	(lang_adjust_rli, set_lang_adjust_rli): New.
	(start_record_layout): Initialize new field unpadded_align.
	(debug_rli): Display it.
	(place_union_field, place_field): Set it.
	(layout_type, case RECORD_TYPE): Call via lang_adjust_rli if set.

From-SVN: r42796
This commit is contained in:
Richard Kenner 2001-06-02 11:14:06 +00:00 committed by Richard Kenner
parent 3af78b060b
commit e0cea8d93a
3 changed files with 45 additions and 8 deletions

View File

@ -1,5 +1,15 @@
Sat Jun 2 06:53:50 2001 Richard Kenner <kenner@vlsi1.ultra.nyu.edu>
* tree.h (struct record_layout_info_s): New field unpadded_align.
(set_lang_adjust_rli): New declaration.
* stor-layout.c (layout_decl): If DECL is packed, but at alignment
it would have if not packed, do not downgrade DECL_ALIGN.
(lang_adjust_rli, set_lang_adjust_rli): New.
(start_record_layout): Initialize new field unpadded_align.
(debug_rli): Display it.
(place_union_field, place_field): Set it.
(layout_type, case RECORD_TYPE): Call via lang_adjust_rli if set.
* print-tree.c (print_node): Don't print "regdecl" when bit doesn't
mean that; use proper names instead.
Print DECL_NO_STATIC_CHAIN.

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@ -381,7 +381,7 @@ layout_decl (decl, known_align)
DECL_BIT_FIELD_TYPE (decl) = DECL_BIT_FIELD (decl) ? type : 0;
if (maximum_field_alignment != 0)
DECL_ALIGN (decl) = MIN (DECL_ALIGN (decl), maximum_field_alignment);
else if (DECL_PACKED (decl))
else if (DECL_PACKED (decl) && known_align % DECL_ALIGN (decl) != 0)
{
DECL_ALIGN (decl) = MIN (DECL_ALIGN (decl), BITS_PER_UNIT);
DECL_USER_ALIGN (decl) = 0;
@ -444,6 +444,18 @@ layout_decl (decl, known_align)
}
}
/* Hook for a front-end function that can modify the record layout as needed
immediately before it is finalized. */
void (*lang_adjust_rli) PARAMS ((record_layout_info)) = 0;
void
set_lang_adjust_rli (f)
void (*f) PARAMS ((record_layout_info));
{
lang_adjust_rli = f;
}
/* Begin laying out type T, which may be a RECORD_TYPE, UNION_TYPE, or
QUAL_UNION_TYPE. Return a pointer to a struct record_layout_info which
is to be passed to all other layout functions for this record. It is the
@ -464,7 +476,7 @@ start_record_layout (t)
declaration, for example) use it -- otherwise, start with a
one-byte alignment. */
rli->record_align = MAX (BITS_PER_UNIT, TYPE_ALIGN (t));
rli->unpacked_align = rli->record_align;
rli->unpacked_align = rli->unpadded_align = rli->record_align;
rli->offset_align = MAX (rli->record_align, BIGGEST_ALIGNMENT);
#ifdef STRUCTURE_SIZE_BOUNDARY
@ -571,8 +583,9 @@ debug_rli (rli)
print_node_brief (stderr, "\noffset", rli->offset, 0);
print_node_brief (stderr, " bitpos", rli->bitpos, 0);
fprintf (stderr, "\nrec_align = %u, unpack_align = %u, off_align = %u\n",
rli->record_align, rli->unpacked_align, rli->offset_align);
fprintf (stderr, "\naligns: rec = %u, unpack = %u, unpad = %u, off = %u\n",
rli->record_align, rli->unpacked_align, rli->unpadded_align,
rli->offset_align);
if (rli->packed_maybe_necessary)
fprintf (stderr, "packed may be necessary\n");
@ -639,13 +652,18 @@ place_union_field (rli, field)
/* Union must be at least as aligned as any field requires. */
rli->record_align = MAX (rli->record_align, desired_align);
rli->unpadded_align = MAX (rli->unpadded_align, desired_align);
#ifdef PCC_BITFIELD_TYPE_MATTERS
/* On the m88000, a bit field of declare type `int' forces the
entire union to have `int' alignment. */
if (PCC_BITFIELD_TYPE_MATTERS && DECL_BIT_FIELD_TYPE (field))
rli->record_align = MAX (rli->record_align,
TYPE_ALIGN (TREE_TYPE (field)));
{
rli->record_align = MAX (rli->record_align,
TYPE_ALIGN (TREE_TYPE (field)));
rli->unpadded_align = MAX (rli->unpadded_align,
TYPE_ALIGN (TREE_TYPE (field)));
}
#endif
/* We assume the union's size will be a multiple of a byte so we don't
@ -773,9 +791,9 @@ place_field (rli, field)
type_align = MIN (type_align, BITS_PER_UNIT);
rli->record_align = MAX (rli->record_align, type_align);
rli->unpadded_align = MAX (rli->unpadded_align, DECL_ALIGN (field));
if (warn_packed)
rli->unpacked_align = MAX (rli->unpacked_align,
TYPE_ALIGN (type));
rli->unpacked_align = MAX (rli->unpacked_align, TYPE_ALIGN (type));
}
}
else
@ -783,6 +801,7 @@ place_field (rli, field)
{
rli->record_align = MAX (rli->record_align, desired_align);
rli->unpacked_align = MAX (rli->unpacked_align, TYPE_ALIGN (type));
rli->unpadded_align = MAX (rli->unpadded_align, DECL_ALIGN (field));
}
if (warn_packed && DECL_PACKED (field))
@ -1498,6 +1517,9 @@ layout_type (type)
if (TREE_CODE (type) == QUAL_UNION_TYPE)
TYPE_FIELDS (type) = nreverse (TYPE_FIELDS (type));
if (lang_adjust_rli)
(*lang_adjust_rli) (rli);
/* Finish laying out the record. */
finish_record_layout (rli);
}

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@ -2118,12 +2118,17 @@ typedef struct record_layout_info_s
unsigned int record_align;
/* The alignment of the record so far, not including padding, in bits. */
unsigned int unpacked_align;
/* The alignment of the record so far, allowing for the record to be
padded only at the end, in bits. */
unsigned int unpadded_align;
/* The static variables (i.e., class variables, as opposed to
instance variables) encountered in T. */
tree pending_statics;
int packed_maybe_necessary;
} *record_layout_info;
extern void set_lang_adjust_rli PARAMS ((void (*) PARAMS
((record_layout_info))));
extern record_layout_info start_record_layout PARAMS ((tree));
extern tree bit_from_pos PARAMS ((tree, tree));
extern tree byte_from_pos PARAMS ((tree, tree));