May be overridden by front-ends. */
unsigned int set_alignment = 0;
-static tree layout_record PARAMS ((tree));
-static void layout_union PARAMS ((tree));
+static void finalize_record_size PARAMS ((record_layout_info));
+static void finalize_type_size PARAMS ((tree));
+static void place_union_field PARAMS ((record_layout_info, tree));
\f
/* SAVE_EXPRs for sizes of types and decls, waiting to be expanded. */
int immediate_size_expand;
+/* Get a list of all the objects put on the pending sizes list. */
+
tree
get_pending_sizes ()
{
return chain;
}
+/* Put a chain of objects into the pending sizes list, which must be
+ empty. */
+
void
put_pending_sizes (chain)
tree chain;
Also, we would like to pass const0_rtx here, but don't have it. */
expand_expr (size, expand_expr (integer_zero_node, NULL_PTR, VOIDmode, 0),
VOIDmode, 0);
- else if (cfun != 0
- && cfun->x_dont_save_pending_sizes_p)
+ else if (cfun != 0 && cfun->x_dont_save_pending_sizes_p)
/* The front-end doesn't want us to keep a list of the expressions
that determine sizes for variable size objects. */
;
{
register enum machine_mode mode;
- if (limit && size > (unsigned int)(MAX_FIXED_MODE_SIZE))
+ if (limit && size > MAX_FIXED_MODE_SIZE)
return BLKmode;
/* Get the first mode which has this size, in the specified class. */
for (mode = GET_CLASS_NARROWEST_MODE (class); mode != VOIDmode;
mode = GET_MODE_WIDER_MODE (mode))
- if ((unsigned int)GET_MODE_BITSIZE (mode) == size)
+ if (GET_MODE_BITSIZE (mode) == size)
return mode;
return BLKmode;
}
+/* Similar, except passed a tree node. */
+
+enum machine_mode
+mode_for_size_tree (size, class, limit)
+ tree size;
+ enum mode_class class;
+ int limit;
+{
+ if (TREE_CODE (size) != INTEGER_CST
+ /* What we really want to say here is that the size can fit in a
+ host integer, but we know there's no way we'd find a mode for
+ this many bits, so there's no point in doing the precise test. */
+ || compare_tree_int (size, 1000) > 0)
+ return BLKmode;
+ else
+ return mode_for_size (TREE_INT_CST_LOW (size), class, limit);
+}
+
/* Similar, but never return BLKmode; return the narrowest mode that
contains at least the requested number of bits. */
specified class. */
for (mode = GET_CLASS_NARROWEST_MODE (class); mode != VOIDmode;
mode = GET_MODE_WIDER_MODE (mode))
- if ((unsigned int)GET_MODE_BITSIZE (mode) >= size)
+ if (GET_MODE_BITSIZE (mode) >= size)
return mode;
abort ();
case MODE_CC:
default:
- abort();
+ abort ();
}
return mode;
if (type == error_mark_node)
type = void_type_node;
- /* Usually the size and mode come from the data type without change. */
- DECL_MODE (decl) = TYPE_MODE (type);
+ /* Usually the size and mode come from the data type without change,
+ however, the front-end may set the explicit width of the field, so its
+ size may not be the same as the size of its type. This happens with
+ bitfields, of course (an `int' bitfield may be only 2 bits, say), but it
+ also happens with other fields. For example, the C++ front-end creates
+ zero-sized fields corresponding to empty base classes, and depends on
+ layout_type setting DECL_FIELD_BITPOS correctly for the field. Set the
+ size in bytes from the size in bits. If we have already set the mode,
+ don't set it again since we can be called twice for FIELD_DECLs. */
+
TREE_UNSIGNED (decl) = TREE_UNSIGNED (type);
+ if (DECL_MODE (decl) == VOIDmode)
+ DECL_MODE (decl) = TYPE_MODE (type);
+
if (DECL_SIZE (decl) == 0)
{
DECL_SIZE (decl) = TYPE_SIZE (type);
DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (type);
}
- else if (code == FIELD_DECL)
- {
- HOST_WIDE_INT spec_size;
-
- /* The front-end may set the explicit width of the field, so its
- size may not be the same as the size of its type. This happens
- with bitfields, of course (an `int' bitfield may be only 2 bits,
- say), but it also happens with other fields. For example, the
- C++ front-end creates zero-sized fields corresponding to empty
- base classes, and depends on layout_type setting
- DECL_FIELD_BITPOS correctly for the field. */
- if (integer_zerop (DECL_SIZE (decl))
- && DECL_NAME (decl) != NULL_TREE)
- abort ();
-
- /* Size is specified in number of bits. */
- spec_size = TREE_INT_CST_LOW (DECL_SIZE (decl));
- if (spec_size % BITS_PER_UNIT == 0)
- DECL_SIZE_UNIT (decl) = size_int (spec_size / BITS_PER_UNIT);
- else
- DECL_SIZE_UNIT (decl) = 0;
- }
+ else
+ DECL_SIZE_UNIT (decl)
+ = convert (sizetype, size_binop (CEIL_DIV_EXPR, DECL_SIZE (decl),
+ bitsize_unit_node));
/* Force alignment required for the data type.
But if the decl itself wants greater alignment, don't override that.
Likewise, if the decl is packed, don't override it. */
- if (!(code == FIELD_DECL && DECL_BIT_FIELD (decl))
+ if (! (code == FIELD_DECL && DECL_BIT_FIELD (decl))
&& (DECL_ALIGN (decl) == 0
- || (! DECL_PACKED (decl) && TYPE_ALIGN (type) > DECL_ALIGN (decl))))
+ || (! (code == FIELD_DECL && DECL_PACKED (decl))
+ && TYPE_ALIGN (type) > DECL_ALIGN (decl))))
DECL_ALIGN (decl) = TYPE_ALIGN (type);
- /* See if we can use an ordinary integer mode for a bit-field.
- Conditions are: a fixed size that is correct for another mode
- and occupying a complete byte or bytes on proper boundary. */
+ /* For fields, set the bit field type and update the alignment. */
if (code == FIELD_DECL)
{
DECL_BIT_FIELD_TYPE (decl) = DECL_BIT_FIELD (decl) ? type : 0;
DECL_ALIGN (decl) = MIN (DECL_ALIGN (decl), BITS_PER_UNIT);
}
- if (DECL_BIT_FIELD (decl)
+ /* See if we can use an ordinary integer mode for a bit-field.
+ Conditions are: a fixed size that is correct for another mode
+ and occupying a complete byte or bytes on proper boundary. */
+ if (code == FIELD_DECL && DECL_BIT_FIELD (decl)
&& TYPE_SIZE (type) != 0
&& TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST
&& GET_MODE_CLASS (TYPE_MODE (type)) == MODE_INT)
{
register enum machine_mode xmode
- = mode_for_size (TREE_INT_CST_LOW (DECL_SIZE (decl)), MODE_INT, 1);
+ = mode_for_size_tree (DECL_SIZE (decl), MODE_INT, 1);
- if (xmode != BLKmode
- && known_align % GET_MODE_ALIGNMENT (xmode) == 0)
+ if (xmode != BLKmode && known_align >= GET_MODE_ALIGNMENT (xmode))
{
DECL_ALIGN (decl) = MAX (GET_MODE_ALIGNMENT (xmode),
DECL_ALIGN (decl));
DECL_MODE (decl) = xmode;
- DECL_SIZE (decl) = bitsize_int (GET_MODE_BITSIZE (xmode));
- DECL_SIZE_UNIT (decl) = size_int (GET_MODE_SIZE (xmode));
- /* This no longer needs to be accessed as a bit field. */
DECL_BIT_FIELD (decl) = 0;
}
}
/* Turn off DECL_BIT_FIELD if we won't need it set. */
- if (DECL_BIT_FIELD (decl) && TYPE_MODE (type) == BLKmode
- && known_align % TYPE_ALIGN (type) == 0
- && DECL_SIZE_UNIT (decl) != 0
- && DECL_ALIGN (decl) >= TYPE_ALIGN (type))
+ if (code == FIELD_DECL && DECL_BIT_FIELD (decl)
+ && TYPE_MODE (type) == BLKmode && DECL_MODE (decl) == BLKmode
+ && known_align >= TYPE_ALIGN (type)
+ && DECL_ALIGN (decl) >= TYPE_ALIGN (type)
+ && DECL_SIZE_UNIT (decl) != 0)
DECL_BIT_FIELD (decl) = 0;
/* Evaluate nonconstant size only once, either now or as soon as safe. */
/* If requested, warn about definitions of large data objects. */
if (warn_larger_than
- && (TREE_CODE (decl) == VAR_DECL || TREE_CODE (decl) == PARM_DECL)
+ && (code == VAR_DECL || code == PARM_DECL)
&& ! DECL_EXTERNAL (decl))
{
tree size = DECL_SIZE_UNIT (decl);
if (size != 0 && TREE_CODE (size) == INTEGER_CST
- && (TREE_INT_CST_HIGH (size) != 0
- || TREE_INT_CST_LOW (size) > larger_than_size))
+ && compare_tree_int (size, larger_than_size) > 0)
{
- int size_as_int = TREE_INT_CST_LOW (size);
+ unsigned int size_as_int = TREE_INT_CST_LOW (size);
- if (size_as_int == TREE_INT_CST_LOW (size)
- && TREE_INT_CST_HIGH (size) == 0)
+ if (compare_tree_int (size, size_as_int) == 0)
warning_with_decl (decl, "size of `%s' is %d bytes", size_as_int);
else
warning_with_decl (decl, "size of `%s' is larger than %d bytes",
}
}
\f
-/* Lay out a RECORD_TYPE type (a C struct).
- This means laying out the fields, determining their positions,
- and computing the overall size and required alignment of the record.
- Note that if you set the TYPE_ALIGN before calling this
- then the struct is aligned to at least that boundary.
-
- If the type has basetypes, you must call layout_basetypes
- before calling this function.
+/* 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
+ responsibility of the caller to call `free' for the storage returned.
+ Note that garbage collection is not permitted until we finish laying
+ out the record. */
+
+record_layout_info
+start_record_layout (t)
+ tree t;
+{
+ record_layout_info rli
+ = (record_layout_info) xmalloc (sizeof (struct record_layout_info));
- The return value is a list of static members of the record.
- They still need to be laid out. */
+ rli->t = t;
-static tree
-layout_record (rec)
- tree rec;
-{
- register tree field;
- unsigned int record_align = MAX (BITS_PER_UNIT, TYPE_ALIGN (rec));
- unsigned int unpacked_align = record_align;
- /* These must be laid out *after* the record is. */
- tree pending_statics = NULL_TREE;
- /* Record size so far is CONST_SIZE + VAR_SIZE bits,
- where CONST_SIZE is an integer
- and VAR_SIZE is a tree expression.
- If VAR_SIZE is null, the size is just CONST_SIZE.
- Naturally we try to avoid using VAR_SIZE. */
- HOST_WIDE_INT const_size = 0;
- tree var_size = 0;
- /* Once we start using VAR_SIZE, this is the maximum alignment
- that we know VAR_SIZE has. */
- unsigned int var_align = BITS_PER_UNIT;
- int packed_maybe_necessary = 0;
+ /* If the type has a minimum specified alignment (via an attribute
+ 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->offset_align = MAX (rli->record_align, BIGGEST_ALIGNMENT);
#ifdef STRUCTURE_SIZE_BOUNDARY
/* Packed structures don't need to have minimum size. */
- if (! TYPE_PACKED (rec))
- record_align = MAX (record_align, STRUCTURE_SIZE_BOUNDARY);
+ if (! TYPE_PACKED (t))
+ rli->record_align = MAX (rli->record_align, STRUCTURE_SIZE_BOUNDARY);
#endif
- for (field = TYPE_FIELDS (rec); field; field = TREE_CHAIN (field))
+ rli->offset = size_zero_node;
+ rli->bitpos = bitsize_zero_node;
+ rli->pending_statics = 0;
+ rli->packed_maybe_necessary = 0;
+
+ return rli;
+}
+
+/* These four routines perform computations that convert between
+ the offset/bitpos forms and byte and bit offsets. */
+
+tree
+bit_from_pos (offset, bitpos)
+ tree offset, bitpos;
+{
+ return size_binop (PLUS_EXPR, bitpos,
+ size_binop (MULT_EXPR, convert (bitsizetype, offset),
+ bitsize_unit_node));
+}
+
+tree
+byte_from_pos (offset, bitpos)
+ tree offset, bitpos;
+{
+ return size_binop (PLUS_EXPR, offset,
+ convert (sizetype,
+ size_binop (TRUNC_DIV_EXPR, bitpos,
+ bitsize_unit_node)));
+}
+
+void
+pos_from_byte (poffset, pbitpos, off_align, pos)
+ tree *poffset, *pbitpos;
+ unsigned int off_align;
+ tree pos;
+{
+ *poffset
+ = size_binop (MULT_EXPR,
+ convert (sizetype,
+ size_binop (FLOOR_DIV_EXPR, pos,
+ bitsize_int (off_align
+ / BITS_PER_UNIT))),
+ size_int (off_align / BITS_PER_UNIT));
+ *pbitpos = size_binop (MULT_EXPR,
+ size_binop (FLOOR_MOD_EXPR, pos,
+ bitsize_int (off_align / BITS_PER_UNIT)),
+ bitsize_unit_node);
+}
+
+void
+pos_from_bit (poffset, pbitpos, off_align, pos)
+ tree *poffset, *pbitpos;
+ unsigned int off_align;
+ tree pos;
+{
+ *poffset = size_binop (MULT_EXPR,
+ convert (sizetype,
+ size_binop (FLOOR_DIV_EXPR, pos,
+ bitsize_int (off_align))),
+ size_int (off_align / BITS_PER_UNIT));
+ *pbitpos = size_binop (FLOOR_MOD_EXPR, pos, bitsize_int (off_align));
+}
+
+/* Given a pointer to bit and byte offsets and an offset alignment,
+ normalize the offsets so they are within the alignment. */
+
+void
+normalize_offset (poffset, pbitpos, off_align)
+ tree *poffset, *pbitpos;
+ unsigned int off_align;
+{
+ /* If the bit position is now larger than it should be, adjust it
+ downwards. */
+ if (compare_tree_int (*pbitpos, off_align) >= 0)
{
- unsigned int known_align = var_size ? var_align : const_size;
- unsigned int desired_align = 0;
- tree type = TREE_TYPE (field);
+ tree extra_aligns = size_binop (FLOOR_DIV_EXPR, *pbitpos,
+ bitsize_int (off_align));
+
+ *poffset
+ = size_binop (PLUS_EXPR, *poffset,
+ size_binop (MULT_EXPR, convert (sizetype, extra_aligns),
+ size_int (off_align / BITS_PER_UNIT)));
+
+ *pbitpos
+ = size_binop (FLOOR_MOD_EXPR, *pbitpos, bitsize_int (off_align));
+ }
+}
- /* If FIELD is static, then treat it like a separate variable,
- not really like a structure field.
- If it is a FUNCTION_DECL, it's a method.
- In both cases, all we do is lay out the decl,
- and we do it *after* the record is laid out. */
+/* Print debugging information about the information in RLI. */
- if (TREE_CODE (field) == VAR_DECL)
- {
- pending_statics = tree_cons (NULL_TREE, field, pending_statics);
- continue;
- }
+void
+debug_rli (rli)
+ record_layout_info rli;
+{
+ print_node_brief (stderr, "type", rli->t, 0);
+ print_node_brief (stderr, "\noffset", rli->offset, 0);
+ print_node_brief (stderr, " bitpos", rli->bitpos, 0);
- /* Enumerators and enum types which are local to this class need not
- be laid out. Likewise for initialized constant fields. */
- if (TREE_CODE (field) != FIELD_DECL)
- continue;
+ fprintf (stderr, "\nrec_align = %u, unpack_align = %u, off_align = %u\n",
+ rli->record_align, rli->unpacked_align, rli->offset_align);
+ if (rli->packed_maybe_necessary)
+ fprintf (stderr, "packed may be necessary\n");
- /* Lay out the field so we know what alignment it needs.
- For a packed field, use the alignment as specified,
- disregarding what the type would want. */
- if (DECL_PACKED (field))
- desired_align = DECL_ALIGN (field);
- layout_decl (field, known_align);
- if (! DECL_PACKED (field))
- desired_align = DECL_ALIGN (field);
- /* Some targets (i.e. VMS) limit struct field alignment
- to a lower boundary than alignment of variables. */
-#ifdef BIGGEST_FIELD_ALIGNMENT
- desired_align = MIN (desired_align, BIGGEST_FIELD_ALIGNMENT);
-#endif
-#ifdef ADJUST_FIELD_ALIGN
- desired_align = ADJUST_FIELD_ALIGN (field, desired_align);
-#endif
+ if (rli->pending_statics)
+ {
+ fprintf (stderr, "pending statics:\n");
+ debug_tree (rli->pending_statics);
+ }
+}
- /* Record must have at least as much alignment as any field.
- Otherwise, the alignment of the field within the record
- is meaningless. */
+/* Given an RLI with a possibly-incremented BITPOS, adjust OFFSET and
+ BITPOS if necessary to keep BITPOS below OFFSET_ALIGN. */
-#ifdef PCC_BITFIELD_TYPE_MATTERS
- if (PCC_BITFIELD_TYPE_MATTERS && type != error_mark_node
- && DECL_BIT_FIELD_TYPE (field)
- && ! integer_zerop (TYPE_SIZE (type)))
- {
- /* For these machines, a zero-length field does not
- affect the alignment of the structure as a whole.
- It does, however, affect the alignment of the next field
- within the structure. */
- if (! integer_zerop (DECL_SIZE (field)))
- record_align = MAX (record_align, desired_align);
- else if (! DECL_PACKED (field))
- desired_align = TYPE_ALIGN (type);
- /* A named bit field of declared type `int'
- forces the entire structure to have `int' alignment. */
- if (DECL_NAME (field) != 0)
- {
- unsigned int type_align = TYPE_ALIGN (type);
+void
+normalize_rli (rli)
+ record_layout_info rli;
+{
+ normalize_offset (&rli->offset, &rli->bitpos, rli->offset_align);
+}
- if (maximum_field_alignment != 0)
- type_align = MIN (type_align, maximum_field_alignment);
- else if (DECL_PACKED (field))
- type_align = MIN (type_align, BITS_PER_UNIT);
+/* Returns the size in bytes allocated so far. */
- record_align = MAX (record_align, type_align);
- if (warn_packed)
- unpacked_align = MAX (unpacked_align, TYPE_ALIGN (type));
- }
- }
- else
-#endif
- {
- record_align = MAX (record_align, desired_align);
- if (warn_packed)
- unpacked_align = MAX (unpacked_align, TYPE_ALIGN (type));
- }
+tree
+rli_size_unit_so_far (rli)
+ record_layout_info rli;
+{
+ return byte_from_pos (rli->offset, rli->bitpos);
+}
- if (warn_packed && DECL_PACKED (field))
- {
- if (const_size % TYPE_ALIGN (type) == 0
- || (var_align % TYPE_ALIGN (type) == 0 && var_size != NULL_TREE))
- {
- if (TYPE_ALIGN (type) > desired_align)
- {
- if (STRICT_ALIGNMENT)
- warning_with_decl (field, "packed attribute causes inefficient alignment for `%s'");
- else
- warning_with_decl (field, "packed attribute is unnecessary for `%s'");
- }
- }
- else
- packed_maybe_necessary = 1;
- }
+/* Returns the size in bits allocated so far. */
- /* Does this field automatically have alignment it needs
- by virtue of the fields that precede it and the record's
- own alignment? */
+tree
+rli_size_so_far (rli)
+ record_layout_info rli;
+{
+ return bit_from_pos (rli->offset, rli->bitpos);
+}
- if (const_size % desired_align != 0
- || (var_align % desired_align != 0 && var_size != NULL_TREE))
- {
- /* No, we need to skip space before this field.
- Bump the cumulative size to multiple of field alignment. */
+/* Called from place_field to handle unions. */
- if (warn_padded)
- warning_with_decl (field, "padding struct to align `%s'");
+static void
+place_union_field (rli, field)
+ record_layout_info rli;
+ tree field;
+{
+ layout_decl (field, 0);
+
+ DECL_FIELD_OFFSET (field) = size_zero_node;
+ DECL_FIELD_BIT_OFFSET (field) = bitsize_zero_node;
+ DECL_OFFSET_ALIGN (field) = BIGGEST_ALIGNMENT;
- if (var_size == NULL_TREE || var_align % desired_align == 0)
- const_size
- = CEIL (const_size, desired_align) * desired_align;
- else
- {
- if (const_size > 0)
- var_size = size_binop (PLUS_EXPR, var_size,
- bitsize_int (const_size));
- const_size = 0;
- var_size = round_up (var_size, desired_align);
- var_align = MIN (var_align, desired_align);
- }
- }
+ /* Union must be at least as aligned as any field requires. */
+ rli->record_align = MAX (rli->record_align, DECL_ALIGN (field));
#ifdef PCC_BITFIELD_TYPE_MATTERS
- if (PCC_BITFIELD_TYPE_MATTERS
- && TREE_CODE (field) == FIELD_DECL
- && type != error_mark_node
- && DECL_BIT_FIELD_TYPE (field)
- && !DECL_PACKED (field)
- && maximum_field_alignment == 0
- && !integer_zerop (DECL_SIZE (field)))
- {
- unsigned int type_align = TYPE_ALIGN (type);
- register tree dsize = DECL_SIZE (field);
- int field_size = TREE_INT_CST_LOW (dsize);
-
- /* A bit field may not span more units of alignment of its type
- than its type itself. Advance to next boundary if necessary. */
- if (((const_size + field_size + type_align - 1) / type_align
- - const_size / type_align)
- > TREE_INT_CST_LOW (TYPE_SIZE (TREE_TYPE (field))) / type_align)
- const_size = CEIL (const_size, type_align) * type_align;
- }
+ /* 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)));
#endif
-/* No existing machine description uses this parameter.
- So I have made it in this aspect identical to PCC_BITFIELD_TYPE_MATTERS. */
-#ifdef BITFIELD_NBYTES_LIMITED
- if (BITFIELD_NBYTES_LIMITED
- && TREE_CODE (field) == FIELD_DECL
- && type != error_mark_node
- && DECL_BIT_FIELD_TYPE (field)
- && !DECL_PACKED (field)
- && !integer_zerop (DECL_SIZE (field)))
+ /* We assume the union's size will be a multiple of a byte so we don't
+ bother with BITPOS. */
+ if (TREE_CODE (rli->t) == UNION_TYPE)
+ rli->offset = size_binop (MAX_EXPR, rli->offset, DECL_SIZE_UNIT (field));
+ else if (TREE_CODE (rli->t) == QUAL_UNION_TYPE)
+ rli->offset = fold (build (COND_EXPR, sizetype,
+ DECL_QUALIFIER (field),
+ DECL_SIZE_UNIT (field), rli->offset));
+}
+
+/* RLI contains information about the layout of a RECORD_TYPE. FIELD
+ is a FIELD_DECL to be added after those fields already present in
+ T. (FIELD is not actually added to the TYPE_FIELDS list here;
+ callers that desire that behavior must manually perform that step.) */
+
+void
+place_field (rli, field)
+ record_layout_info rli;
+ tree field;
+{
+ /* The alignment required for FIELD. */
+ unsigned int desired_align;
+ /* The alignment FIELD would have if we just dropped it into the
+ record as it presently stands. */
+ unsigned int known_align;
+ unsigned int actual_align;
+ /* The type of this field. */
+ tree type = TREE_TYPE (field);
+
+ /* If FIELD is static, then treat it like a separate variable, not
+ really like a structure field. If it is a FUNCTION_DECL, it's a
+ method. In both cases, all we do is lay out the decl, and we do
+ it *after* the record is laid out. */
+ if (TREE_CODE (field) == VAR_DECL)
+ {
+ rli->pending_statics = tree_cons (NULL_TREE, field,
+ rli->pending_statics);
+ return;
+ }
+
+ /* Enumerators and enum types which are local to this class need not
+ be laid out. Likewise for initialized constant fields. */
+ else if (TREE_CODE (field) != FIELD_DECL)
+ return;
+
+ /* Unions are laid out very differently than records, so split
+ that code off to another function. */
+ else if (TREE_CODE (rli->t) != RECORD_TYPE)
+ {
+ place_union_field (rli, field);
+ return;
+ }
+
+ /* Work out the known alignment so far. Note that A & (-A) is the
+ value of the least-significant bit in A that is one. */
+ if (! integer_zerop (rli->bitpos))
+ known_align = (tree_low_cst (rli->bitpos, 1)
+ & - tree_low_cst (rli->bitpos, 1));
+ else if (integer_zerop (rli->offset))
+ known_align = BIGGEST_ALIGNMENT;
+ else if (host_integerp (rli->offset, 1))
+ known_align = (BITS_PER_UNIT
+ * (tree_low_cst (rli->offset, 1)
+ & - tree_low_cst (rli->offset, 1)));
+ else
+ known_align = rli->offset_align;
+
+ /* Lay out the field so we know what alignment it needs. For a
+ packed field, use the alignment as specified, disregarding what
+ the type would want. */
+ desired_align = DECL_ALIGN (field);
+ layout_decl (field, known_align);
+ if (! DECL_PACKED (field))
+ desired_align = DECL_ALIGN (field);
+
+ /* Some targets (i.e. VMS) limit struct field alignment
+ to a lower boundary than alignment of variables. */
+#ifdef BIGGEST_FIELD_ALIGNMENT
+ desired_align = MIN (desired_align, BIGGEST_FIELD_ALIGNMENT);
+#endif
+#ifdef ADJUST_FIELD_ALIGN
+ desired_align = ADJUST_FIELD_ALIGN (field, desired_align);
+#endif
+
+ /* Record must have at least as much alignment as any field.
+ Otherwise, the alignment of the field within the record is
+ meaningless. */
+#ifdef PCC_BITFIELD_TYPE_MATTERS
+ if (PCC_BITFIELD_TYPE_MATTERS && type != error_mark_node
+ && DECL_BIT_FIELD_TYPE (field)
+ && ! integer_zerop (TYPE_SIZE (type)))
+ {
+ /* For these machines, a zero-length field does not
+ affect the alignment of the structure as a whole.
+ It does, however, affect the alignment of the next field
+ within the structure. */
+ if (! integer_zerop (DECL_SIZE (field)))
+ rli->record_align = MAX (rli->record_align, desired_align);
+ else if (! DECL_PACKED (field))
+ desired_align = TYPE_ALIGN (type);
+
+ /* A named bit field of declared type `int'
+ forces the entire structure to have `int' alignment. */
+ if (DECL_NAME (field) != 0)
{
unsigned int type_align = TYPE_ALIGN (type);
- register tree dsize = DECL_SIZE (field);
- int field_size = TREE_INT_CST_LOW (dsize);
if (maximum_field_alignment != 0)
type_align = MIN (type_align, maximum_field_alignment);
- /* ??? This test is opposite the test in the containing if
- statement, so this code is unreachable currently. */
else if (DECL_PACKED (field))
type_align = MIN (type_align, BITS_PER_UNIT);
- /* A bit field may not span the unit of alignment of its type.
- Advance to next boundary if necessary. */
- /* ??? This code should match the code above for the
- PCC_BITFIELD_TYPE_MATTERS case. */
- if (const_size / type_align
- != (const_size + field_size - 1) / type_align)
- const_size = CEIL (const_size, type_align) * type_align;
+ rli->record_align = MAX (rli->record_align, type_align);
+ if (warn_packed)
+ rli->unpacked_align = MAX (rli->unpacked_align,
+ TYPE_ALIGN (type));
}
+ }
+ else
#endif
+ {
+ rli->record_align = MAX (rli->record_align, desired_align);
+ rli->unpacked_align = MAX (rli->unpacked_align, TYPE_ALIGN (type));
+ }
+
+ if (warn_packed && DECL_PACKED (field))
+ {
+ if (known_align > TYPE_ALIGN (type))
+ {
+ if (TYPE_ALIGN (type) > desired_align)
+ {
+ if (STRICT_ALIGNMENT)
+ warning_with_decl (field, "packed attribute causes inefficient alignment for `%s'");
+ else
+ warning_with_decl (field, "packed attribute is unnecessary for `%s'");
+ }
+ }
+ else
+ rli->packed_maybe_necessary = 1;
+ }
+
+ /* Does this field automatically have alignment it needs by virtue
+ of the fields that precede it and the record's own alignment? */
+ if (known_align < desired_align)
+ {
+ /* No, we need to skip space before this field.
+ Bump the cumulative size to multiple of field alignment. */
- /* Size so far becomes the position of this field. */
+ if (warn_padded)
+ warning_with_decl (field, "padding struct to align `%s'");
- if (var_size && const_size)
- DECL_FIELD_BITPOS (field)
- = size_binop (PLUS_EXPR, var_size, bitsize_int (const_size));
- else if (var_size)
- DECL_FIELD_BITPOS (field) = var_size;
+ /* If the alignment is still within offset_align, just align
+ the bit position. */
+ if (desired_align < rli->offset_align)
+ rli->bitpos = round_up (rli->bitpos, desired_align);
else
{
- DECL_FIELD_BITPOS (field) = bitsize_int (const_size);
-
- /* If this field ended up more aligned than we thought it
- would be (we approximate this by seeing if its position
- changed), lay out the field again; perhaps we can use an
- integral mode for it now. */
- if (known_align != const_size)
- layout_decl (field, const_size);
+ /* First adjust OFFSET by the partial bits, then align. */
+ rli->offset
+ = size_binop (PLUS_EXPR, rli->offset,
+ convert (sizetype,
+ size_binop (CEIL_DIV_EXPR, rli->bitpos,
+ bitsize_unit_node)));
+ rli->bitpos = bitsize_zero_node;
+
+ rli->offset = round_up (rli->offset, desired_align / BITS_PER_UNIT);
}
- /* Now add size of this field to the size of the record. */
+ if (! TREE_CONSTANT (rli->offset))
+ rli->offset_align = desired_align;
- {
- register tree dsize = DECL_SIZE (field);
-
- /* This can happen when we have an invalid nested struct definition,
- such as struct j { struct j { int i; } }. The error message is
- printed in finish_struct. */
- if (dsize == 0)
- /* Do nothing. */;
- else if (TREE_CODE (dsize) == INTEGER_CST
- && ! TREE_CONSTANT_OVERFLOW (dsize)
- && TREE_INT_CST_HIGH (dsize) == 0
- && TREE_INT_CST_LOW (dsize) + const_size >= const_size)
- /* Use const_size if there's no overflow. */
- const_size += TREE_INT_CST_LOW (dsize);
- else
- {
- if (var_size == NULL_TREE)
- var_size = dsize;
- else
- var_size = size_binop (PLUS_EXPR, var_size, dsize);
- }
- }
}
- /* Work out the total size and alignment of the record
- as one expression and store in the record type.
- Round it up to a multiple of the record's alignment. */
+ /* Handle compatibility with PCC. Note that if the record has any
+ variable-sized fields, we need not worry about compatibility. */
+#ifdef PCC_BITFIELD_TYPE_MATTERS
+ if (PCC_BITFIELD_TYPE_MATTERS
+ && TREE_CODE (field) == FIELD_DECL
+ && type != error_mark_node
+ && DECL_BIT_FIELD (field)
+ && ! DECL_PACKED (field)
+ && maximum_field_alignment == 0
+ && ! integer_zerop (DECL_SIZE (field))
+ && host_integerp (DECL_SIZE (field), 1)
+ && host_integerp (rli->offset, 1)
+ && host_integerp (TYPE_SIZE (type), 1))
+ {
+ unsigned int type_align = TYPE_ALIGN (type);
+ tree dsize = DECL_SIZE (field);
+ HOST_WIDE_INT field_size = tree_low_cst (dsize, 1);
+ HOST_WIDE_INT offset = tree_low_cst (rli->offset, 0);
+ HOST_WIDE_INT bit_offset = tree_low_cst (rli->bitpos, 0);
+
+ /* A bit field may not span more units of alignment of its type
+ than its type itself. Advance to next boundary if necessary. */
+ if ((((offset * BITS_PER_UNIT + bit_offset + field_size +
+ type_align - 1)
+ / type_align)
+ - (offset * BITS_PER_UNIT + bit_offset) / type_align)
+ > tree_low_cst (TYPE_SIZE (type), 1) / type_align)
+ rli->bitpos = round_up (rli->bitpos, type_align);
+ }
+#endif
- if (var_size == NULL_TREE)
- TYPE_SIZE (rec) = bitsize_int (const_size);
- else
+#ifdef BITFIELD_NBYTES_LIMITED
+ if (BITFIELD_NBYTES_LIMITED
+ && TREE_CODE (field) == FIELD_DECL
+ && type != error_mark_node
+ && DECL_BIT_FIELD_TYPE (field)
+ && ! DECL_PACKED (field)
+ && ! integer_zerop (DECL_SIZE (field))
+ && host_integerp (DECL_SIZE (field), 1)
+ && host_integerp (rli->size, 1)
+ && host_integerp (TYPE_SIZE (type), 1))
{
- if (const_size)
- var_size = size_binop (PLUS_EXPR, var_size, bitsize_int (const_size));
+ unsigned int type_align = TYPE_ALIGN (type);
+ tree dsize = DECL_SIZE (field);
+ HOST_WIDE_INT field_size = tree_low_cst (dsize, 1);
+ HOST_WIDE_INT offset = tree_low_cst (rli->offset, 0);
+ HOST_WIDE_INT bit_offset = tree_low_cst (rli->bitpos, 0);
+
+ if (maximum_field_alignment != 0)
+ type_align = MIN (type_align, maximum_field_alignment);
+ /* ??? This test is opposite the test in the containing if
+ statement, so this code is unreachable currently. */
+ else if (DECL_PACKED (field))
+ type_align = MIN (type_align, BITS_PER_UNIT);
+
+ /* A bit field may not span the unit of alignment of its type.
+ Advance to next boundary if necessary. */
+ /* ??? This code should match the code above for the
+ PCC_BITFIELD_TYPE_MATTERS case. */
+ if ((offset * BITS_PER_UNIT + bit_offset) / type_align
+ != ((offset * BITS_PER_UNIT + bit_offset + field_size - 1)
+ / type_align))
+ rli->bitpos = round_up (rli->bitpos, type_align);
+ }
+#endif
- TYPE_SIZE (rec) = var_size;
+ /* Offset so far becomes the position of this field after normalizing. */
+ normalize_rli (rli);
+ DECL_FIELD_OFFSET (field) = rli->offset;
+ DECL_FIELD_BIT_OFFSET (field) = rli->bitpos;
+ DECL_OFFSET_ALIGN (field) = rli->offset_align;
+
+ /* If this field ended up more aligned than we thought it would be (we
+ approximate this by seeing if its position changed), lay out the field
+ again; perhaps we can use an integral mode for it now. */
+ if (! integer_zerop (DECL_FIELD_BIT_OFFSET (field)))
+ actual_align = (tree_low_cst (DECL_FIELD_BIT_OFFSET (field), 1)
+ & - tree_low_cst (DECL_FIELD_BIT_OFFSET (field), 1));
+ else if (integer_zerop (DECL_FIELD_OFFSET (field)))
+ actual_align = BIGGEST_ALIGNMENT;
+ else if (host_integerp (DECL_FIELD_OFFSET (field), 1))
+ actual_align = (BITS_PER_UNIT
+ * (tree_low_cst (DECL_FIELD_OFFSET (field), 1)
+ & - tree_low_cst (DECL_FIELD_OFFSET (field), 1)));
+ else
+ actual_align = DECL_OFFSET_ALIGN (field);
+
+ if (known_align != actual_align)
+ layout_decl (field, actual_align);
+
+ /* Now add size of this field to the size of the record. If the size is
+ not constant, treat the field as being a multiple of bytes and just
+ adjust the offset, resetting the bit position. Otherwise, apportion the
+ size amongst the bit position and offset. First handle the case of an
+ unspecified size, which can happen when we have an invalid nested struct
+ definition, such as struct j { struct j { int i; } }. The error message
+ is printed in finish_struct. */
+ if (DECL_SIZE (field) == 0)
+ /* Do nothing. */;
+ else if (! TREE_CONSTANT (DECL_SIZE_UNIT (field)))
+ {
+ rli->offset
+ = size_binop (PLUS_EXPR, rli->offset,
+ convert (sizetype,
+ size_binop (CEIL_DIV_EXPR, rli->bitpos,
+ bitsize_unit_node)));
+ rli->offset
+ = size_binop (PLUS_EXPR, rli->offset, DECL_SIZE_UNIT (field));
+ rli->bitpos = bitsize_zero_node;
+ rli->offset_align = MIN (rli->offset_align, DECL_ALIGN (field));
+ }
+ else
+ {
+ rli->bitpos = size_binop (PLUS_EXPR, rli->bitpos, DECL_SIZE (field));
+ normalize_rli (rli);
}
+}
+
+/* Assuming that all the fields have been laid out, this function uses
+ RLI to compute the final TYPE_SIZE, TYPE_ALIGN, etc. for the type
+ inidicated by RLI. */
+
+static void
+finalize_record_size (rli)
+ record_layout_info rli;
+{
+ tree unpadded_size, unpadded_size_unit;
+
+ /* Now we want just byte and bit offsets, so set the offset alignment
+ to be a byte and then normalize. */
+ rli->offset_align = BITS_PER_UNIT;
+ normalize_rli (rli);
/* Determine the desired alignment. */
#ifdef ROUND_TYPE_ALIGN
- TYPE_ALIGN (rec) = ROUND_TYPE_ALIGN (rec, TYPE_ALIGN (rec), record_align);
+ TYPE_ALIGN (rli->t) = ROUND_TYPE_ALIGN (rli->t, TYPE_ALIGN (rli->t),
+ rli->record_align);
#else
- TYPE_ALIGN (rec) = MAX (TYPE_ALIGN (rec), record_align);
+ TYPE_ALIGN (rli->t) = MAX (TYPE_ALIGN (rli->t), rli->record_align);
#endif
+ /* Compute the size so far. Be sure to allow for extra bits in the
+ size in bytes. We have guaranteed above that it will be no more
+ than a single byte. */
+ unpadded_size = rli_size_so_far (rli);
+ unpadded_size_unit = rli_size_unit_so_far (rli);
+ if (! integer_zerop (rli->bitpos))
+ unpadded_size_unit
+ = size_binop (PLUS_EXPR, unpadded_size_unit, size_one_node);
+
/* Record the un-rounded size in the binfo node. But first we check
the size of TYPE_BINFO to make sure that BINFO_SIZE is available. */
- if (TYPE_BINFO (rec) && TREE_VEC_LENGTH (TYPE_BINFO (rec)) > 6)
+ if (TYPE_BINFO (rli->t) && TREE_VEC_LENGTH (TYPE_BINFO (rli->t)) > 6)
{
- TYPE_BINFO_SIZE (rec) = TYPE_SIZE (rec);
- TYPE_BINFO_SIZE_UNIT (rec)
- = convert (sizetype,
- size_binop (FLOOR_DIV_EXPR, TYPE_SIZE (rec),
- bitsize_int (BITS_PER_UNIT)));
+ TYPE_BINFO_SIZE (rli->t) = unpadded_size;
+ TYPE_BINFO_SIZE_UNIT (rli->t) = unpadded_size_unit;
}
-
- {
- tree unpadded_size = TYPE_SIZE (rec);
+ /* Round the size up to be a multiple of the required alignment */
#ifdef ROUND_TYPE_SIZE
- TYPE_SIZE (rec) = ROUND_TYPE_SIZE (rec, TYPE_SIZE (rec), TYPE_ALIGN (rec));
+ TYPE_SIZE (rli->t) = ROUND_TYPE_SIZE (rli->t, unpadded_size,
+ TYPE_ALIGN (rli->t));
+ TYPE_SIZE_UNIT (rli->t)
+ = ROUND_TYPE_SIZE_UNIT (rli->t, unpaded_size_unit,
+ TYPE_ALIGN (rli->t) / BITS_PER_UNIT);
#else
- /* Round the size up to be a multiple of the required alignment */
- TYPE_SIZE (rec) = round_up (TYPE_SIZE (rec), TYPE_ALIGN (rec));
+ TYPE_SIZE (rli->t) = round_up (unpadded_size, TYPE_ALIGN (rli->t));
+ TYPE_SIZE_UNIT (rli->t) = round_up (unpadded_size_unit,
+ TYPE_ALIGN (rli->t) / BITS_PER_UNIT);
#endif
- if (warn_padded && var_size == NULL_TREE
- && simple_cst_equal (unpadded_size, TYPE_SIZE (rec)) == 0)
- warning ("padding struct size to alignment boundary");
- }
+ if (warn_padded && TREE_CONSTANT (unpadded_size)
+ && simple_cst_equal (unpadded_size, TYPE_SIZE (rli->t)) == 0)
+ warning ("padding struct size to alignment boundary");
- if (warn_packed && TYPE_PACKED (rec) && !packed_maybe_necessary
- && var_size == NULL_TREE)
+ if (warn_packed && TREE_CODE (rli->t) == RECORD_TYPE
+ && TYPE_PACKED (rli->t) && ! rli->packed_maybe_necessary
+ && TREE_CONSTANT (unpadded_size))
{
tree unpacked_size;
- TYPE_PACKED (rec) = 0;
#ifdef ROUND_TYPE_ALIGN
- unpacked_align
- = ROUND_TYPE_ALIGN (rec, TYPE_ALIGN (rec), unpacked_align);
+ rli->unpacked_align
+ = ROUND_TYPE_ALIGN (rli->t, TYPE_ALIGN (rli->t), rli->unpacked_align);
#else
- unpacked_align = MAX (TYPE_ALIGN (rec), unpacked_align);
+ rli->unpacked_align = MAX (TYPE_ALIGN (rli->t), rli->unpacked_align);
#endif
+
#ifdef ROUND_TYPE_SIZE
- unpacked_size = ROUND_TYPE_SIZE (rec, TYPE_SIZE (rec), unpacked_align);
+ unpacked_size = ROUND_TYPE_SIZE (rli->t, TYPE_SIZE (rli->t),
+ rli->unpacked_align);
#else
- unpacked_size = round_up (TYPE_SIZE (rec), unpacked_align);
+ unpacked_size = round_up (TYPE_SIZE (rli->t), rli->unpacked_align);
#endif
- if (simple_cst_equal (unpacked_size, TYPE_SIZE (rec)))
+ if (simple_cst_equal (unpacked_size, TYPE_SIZE (rli->t)))
{
- if (TYPE_NAME (rec))
+ TYPE_PACKED (rli->t) = 0;
+
+ if (TYPE_NAME (rli->t))
{
char *name;
- if (TREE_CODE (TYPE_NAME (rec)) == IDENTIFIER_NODE)
- name = IDENTIFIER_POINTER (TYPE_NAME (rec));
+ if (TREE_CODE (TYPE_NAME (rli->t)) == IDENTIFIER_NODE)
+ name = IDENTIFIER_POINTER (TYPE_NAME (rli->t));
else
- name = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (rec)));
+ name = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (rli->t)));
+
if (STRICT_ALIGNMENT)
warning ("packed attribute causes inefficient alignment for `%s'", name);
else
warning ("packed attribute is unnecessary");
}
}
- TYPE_PACKED (rec) = 1;
}
-
- return pending_statics;
}
-\f
-/* Lay out a UNION_TYPE or QUAL_UNION_TYPE type.
- Lay out all the fields, set their positions to zero,
- and compute the size and alignment of the union (maximum of any field).
- Note that if you set the TYPE_ALIGN before calling this
- then the union align is aligned to at least that boundary. */
-static void
-layout_union (rec)
- tree rec;
+/* Compute the TYPE_MODE for the TYPE (which is a RECORD_TYPE). */
+
+void
+compute_record_mode (type)
+ tree type;
{
- register tree field;
- unsigned int union_align = BITS_PER_UNIT;
+ tree field;
+ enum machine_mode mode = VOIDmode;
- /* The size of the union, based on the fields scanned so far,
- is max (CONST_SIZE, VAR_SIZE).
- VAR_SIZE may be null; then CONST_SIZE by itself is the size. */
- register HOST_WIDE_INT const_size = 0;
- register tree var_size = 0;
+ /* Most RECORD_TYPEs have BLKmode, so we start off assuming that.
+ However, if possible, we use a mode that fits in a register
+ instead, in order to allow for better optimization down the
+ line. */
+ TYPE_MODE (type) = BLKmode;
-#ifdef STRUCTURE_SIZE_BOUNDARY
- /* Packed structures don't need to have minimum size. */
- if (! TYPE_PACKED (rec))
- union_align = STRUCTURE_SIZE_BOUNDARY;
-#endif
-
- /* If this is a QUAL_UNION_TYPE, we want to process the fields in
- the reverse order in building the COND_EXPR that denotes its
- size. We reverse them again later. */
- if (TREE_CODE (rec) == QUAL_UNION_TYPE)
- TYPE_FIELDS (rec) = nreverse (TYPE_FIELDS (rec));
+ if (! host_integerp (TYPE_SIZE (type), 1))
+ return;
- for (field = TYPE_FIELDS (rec); field; field = TREE_CHAIN (field))
+ /* A record which has any BLKmode members must itself be
+ BLKmode; it can't go in a register. Unless the member is
+ BLKmode only because it isn't aligned. */
+ for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
{
- tree dsize;
-
- /* Enums which are local to this class need not be laid out. */
- if (TREE_CODE (field) == CONST_DECL || TREE_CODE (field) == TYPE_DECL)
- continue;
+ unsigned HOST_WIDE_INT bitpos;
- layout_decl (field, 0);
- DECL_FIELD_BITPOS (field) = bitsize_int (0);
-
- /* Union must be at least as aligned as any field requires. */
+ if (TREE_CODE (field) != FIELD_DECL)
+ continue;
- union_align = MAX (union_align, DECL_ALIGN (field));
+ if (TREE_CODE (TREE_TYPE (field)) == ERROR_MARK
+ || (TYPE_MODE (TREE_TYPE (field)) == BLKmode
+ && ! TYPE_NO_FORCE_BLK (TREE_TYPE (field)))
+ || ! host_integerp (bit_position (field), 1)
+ || ! host_integerp (DECL_SIZE (field), 1))
+ return;
+
+ bitpos = int_bit_position (field);
+
+ /* Must be BLKmode if any field crosses a word boundary,
+ since extract_bit_field can't handle that in registers. */
+ if (bitpos / BITS_PER_WORD
+ != ((TREE_INT_CST_LOW (DECL_SIZE (field)) + bitpos - 1)
+ / BITS_PER_WORD)
+ /* But there is no problem if the field is entire words. */
+ && tree_low_cst (DECL_SIZE (field), 1) % BITS_PER_WORD != 0)
+ return;
+
+ /* If this field is the whole struct, remember its mode so
+ that, say, we can put a double in a class into a DF
+ register instead of forcing it to live in the stack. */
+ if (field == TYPE_FIELDS (type) && TREE_CHAIN (field) == 0)
+ mode = DECL_MODE (field);
-#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))
- union_align = MAX (union_align, TYPE_ALIGN (TREE_TYPE (field)));
-#endif
+#ifdef STRUCT_FORCE_BLK
+ /* With some targets, eg. c4x, it is sub-optimal
+ to access an aligned BLKmode structure as a scalar. */
+ if (mode == VOIDmode && STRUCT_FORCE_BLK (field))
+ return;
+#endif /* STRUCT_FORCE_BLK */
+ }
- dsize = DECL_SIZE (field);
- if (TREE_CODE (rec) == UNION_TYPE)
- {
- /* Set union_size to max (decl_size, union_size).
- There are more and less general ways to do this.
- Use only CONST_SIZE unless forced to use VAR_SIZE. */
-
- if (TREE_CODE (dsize) == INTEGER_CST
- && ! TREE_CONSTANT_OVERFLOW (dsize)
- && TREE_INT_CST_HIGH (dsize) == 0)
- const_size
- = MAX (const_size, TREE_INT_CST_LOW (dsize));
- else if (var_size == 0)
- var_size = dsize;
- else
- var_size = size_binop (MAX_EXPR, var_size, dsize);
- }
- else if (TREE_CODE (rec) == QUAL_UNION_TYPE)
- var_size = fold (build (COND_EXPR, bitsizetype, DECL_QUALIFIER (field),
- DECL_SIZE (field),
- var_size ? var_size : bitsize_int (0)));
- }
+ if (mode != VOIDmode)
+ /* We only have one real field; use its mode. */
+ TYPE_MODE (type) = mode;
+ else
+ TYPE_MODE (type) = mode_for_size_tree (TYPE_SIZE (type), MODE_INT, 1);
+
+ /* If structure's known alignment is less than what the scalar
+ mode would need, and it matters, then stick with BLKmode. */
+ if (TYPE_MODE (type) != BLKmode
+ && STRICT_ALIGNMENT
+ && ! (TYPE_ALIGN (type) >= BIGGEST_ALIGNMENT
+ || TYPE_ALIGN (type) >= GET_MODE_ALIGNMENT (TYPE_MODE (type))))
+ {
+ /* If this is the only reason this type is BLKmode, then
+ don't force containing types to be BLKmode. */
+ TYPE_NO_FORCE_BLK (type) = 1;
+ TYPE_MODE (type) = BLKmode;
+ }
+}
- if (TREE_CODE (rec) == QUAL_UNION_TYPE)
- TYPE_FIELDS (rec) = nreverse (TYPE_FIELDS (rec));
+/* Compute TYPE_SIZE and TYPE_ALIGN for TYPE, once it has been laid
+ out. */
- /* Determine the ultimate size of the union (in bytes). */
- if (NULL == var_size)
- TYPE_SIZE (rec)
- = bitsize_int (CEIL (const_size, BITS_PER_UNIT) * BITS_PER_UNIT);
+static void
+finalize_type_size (type)
+ tree type;
+{
+ /* Normally, use the alignment corresponding to the mode chosen.
+ However, where strict alignment is not required, avoid
+ over-aligning structures, since most compilers do not do this
+ alignment. */
- else if (const_size == 0)
- TYPE_SIZE (rec) = var_size;
- else
- TYPE_SIZE (rec) = size_binop (MAX_EXPR, var_size,
- round_up (bitsize_int (const_size),
- BITS_PER_UNIT));
+ if (TYPE_MODE (type) != BLKmode && TYPE_MODE (type) != VOIDmode
+ && (STRICT_ALIGNMENT
+ || (TREE_CODE (type) != RECORD_TYPE && TREE_CODE (type) != UNION_TYPE
+ && TREE_CODE (type) != QUAL_UNION_TYPE
+ && TREE_CODE (type) != ARRAY_TYPE)))
+ TYPE_ALIGN (type) = GET_MODE_ALIGNMENT (TYPE_MODE (type));
- /* Determine the desired alignment. */
+ /* Do machine-dependent extra alignment. */
#ifdef ROUND_TYPE_ALIGN
- TYPE_ALIGN (rec) = ROUND_TYPE_ALIGN (rec, TYPE_ALIGN (rec), union_align);
-#else
- TYPE_ALIGN (rec) = MAX (TYPE_ALIGN (rec), union_align);
+ TYPE_ALIGN (type)
+ = ROUND_TYPE_ALIGN (type, TYPE_ALIGN (type), BITS_PER_UNIT);
#endif
+ /* If we failed to find a simple way to calculate the unit size
+ of the type, find it by division. */
+ if (TYPE_SIZE_UNIT (type) == 0 && TYPE_SIZE (type) != 0)
+ /* TYPE_SIZE (type) is computed in bitsizetype. After the division, the
+ result will fit in sizetype. We will get more efficient code using
+ sizetype, so we force a conversion. */
+ TYPE_SIZE_UNIT (type)
+ = convert (sizetype,
+ size_binop (FLOOR_DIV_EXPR, TYPE_SIZE (type),
+ bitsize_unit_node));
+
+ if (TYPE_SIZE (type) != 0)
+ {
#ifdef ROUND_TYPE_SIZE
- TYPE_SIZE (rec) = ROUND_TYPE_SIZE (rec, TYPE_SIZE (rec), TYPE_ALIGN (rec));
+ TYPE_SIZE (type)
+ = ROUND_TYPE_SIZE (type, TYPE_SIZE (type), TYPE_ALIGN (type));
+ TYPE_SIZE_UNIT (type)
+ = ROUND_TYPE_SIZE_UNIT (type, TYPE_SIZE_UNIT (type),
+ TYPE_ALIGN (type) / BITS_PER_UNIT);
#else
- /* Round the size up to be a multiple of the required alignment */
- TYPE_SIZE (rec) = round_up (TYPE_SIZE (rec), TYPE_ALIGN (rec));
+ TYPE_SIZE (type) = round_up (TYPE_SIZE (type), TYPE_ALIGN (type));
+ TYPE_SIZE_UNIT (type)
+ = round_up (TYPE_SIZE_UNIT (type), TYPE_ALIGN (type) / BITS_PER_UNIT);
#endif
+ }
+
+ /* Evaluate nonconstant sizes only once, either now or as soon as safe. */
+ if (TYPE_SIZE (type) != 0 && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
+ TYPE_SIZE (type) = variable_size (TYPE_SIZE (type));
+ if (TYPE_SIZE_UNIT (type) != 0
+ && TREE_CODE (TYPE_SIZE_UNIT (type)) != INTEGER_CST)
+ TYPE_SIZE_UNIT (type) = variable_size (TYPE_SIZE_UNIT (type));
+
+ /* Also layout any other variants of the type. */
+ if (TYPE_NEXT_VARIANT (type)
+ || type != TYPE_MAIN_VARIANT (type))
+ {
+ tree variant;
+ /* Record layout info of this variant. */
+ tree size = TYPE_SIZE (type);
+ tree size_unit = TYPE_SIZE_UNIT (type);
+ unsigned int align = TYPE_ALIGN (type);
+ enum machine_mode mode = TYPE_MODE (type);
+
+ /* Copy it into all variants. */
+ for (variant = TYPE_MAIN_VARIANT (type);
+ variant != 0;
+ variant = TYPE_NEXT_VARIANT (variant))
+ {
+ TYPE_SIZE (variant) = size;
+ TYPE_SIZE_UNIT (variant) = size_unit;
+ TYPE_ALIGN (variant) = align;
+ TYPE_MODE (variant) = mode;
+ }
+ }
+}
+
+/* Do all of the work required to layout the type indicated by RLI,
+ once the fields have been laid out. This function will call `free'
+ for RLI. */
+
+void
+finish_record_layout (rli)
+ record_layout_info rli;
+{
+ /* Compute the final size. */
+ finalize_record_size (rli);
+
+ /* Compute the TYPE_MODE for the record. */
+ compute_record_mode (rli->t);
+
+ /* Lay out any static members. This is done now because their type
+ may use the record's type. */
+ while (rli->pending_statics)
+ {
+ layout_decl (TREE_VALUE (rli->pending_statics), 0);
+ rli->pending_statics = TREE_CHAIN (rli->pending_statics);
+ }
+
+ /* Perform any last tweaks to the TYPE_SIZE, etc. */
+ finalize_type_size (rli->t);
+
+ /* Clean up. */
+ free (rli);
}
\f
/* Calculate the mode, size, and alignment for TYPE.
tree type;
{
int old;
- tree pending_statics;
if (type == 0)
abort ();
if (TYPE_SIZE (type))
return;
- /* Make sure all nodes we allocate are not momentary;
- they must last past the current statement. */
+ /* Make sure all nodes we allocate are not momentary; they must last
+ past the current statement. */
old = suspend_momentary ();
/* Put all our nodes into the same obstack as the type. Also,
break;
case VOID_TYPE:
- TYPE_SIZE (type) = size_zero_node;
- TYPE_SIZE_UNIT (type) = size_zero_node;
+ /* This is an incomplete type and so doesn't have a size. */
TYPE_ALIGN (type) = 1;
TYPE_MODE (type) = VOIDmode;
break;
TYPE_MODE (type) = BLKmode;
if (TYPE_SIZE (type) != 0
- && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST
/* BLKmode elements force BLKmode aggregate;
else extract/store fields may lose. */
&& (TYPE_MODE (TREE_TYPE (type)) != BLKmode
|| TYPE_NO_FORCE_BLK (TREE_TYPE (type))))
{
TYPE_MODE (type)
- = mode_for_size (TREE_INT_CST_LOW (TYPE_SIZE (type)),
- MODE_INT, 1);
+ = mode_for_size_tree (TYPE_SIZE (type), MODE_INT, 1);
- if (STRICT_ALIGNMENT && TYPE_ALIGN (type) < BIGGEST_ALIGNMENT
- && ((int) TYPE_ALIGN (type)
- < TREE_INT_CST_LOW (TYPE_SIZE (type)))
+ if (TYPE_MODE (type) != BLKmode
+ && STRICT_ALIGNMENT && TYPE_ALIGN (type) < BIGGEST_ALIGNMENT
+ && TYPE_ALIGN (type) < GET_MODE_ALIGNMENT (TYPE_MODE (type))
&& TYPE_MODE (type) != BLKmode)
{
TYPE_NO_FORCE_BLK (type) = 1;
}
case RECORD_TYPE:
- pending_statics = layout_record (type);
- TYPE_MODE (type) = BLKmode;
- if (TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST)
- {
- tree field;
- enum machine_mode mode = VOIDmode;
-
- /* A record which has any BLKmode members must itself be BLKmode;
- it can't go in a register.
- Unless the member is BLKmode only because it isn't aligned. */
- for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
- {
- int bitpos;
-
- if (TREE_CODE (field) != FIELD_DECL
- || TREE_CODE (TREE_TYPE (field)) == ERROR_MARK)
- continue;
-
- if (TYPE_MODE (TREE_TYPE (field)) == BLKmode
- && ! TYPE_NO_FORCE_BLK (TREE_TYPE (field)))
- goto record_lose;
-
- if (TREE_CODE (DECL_FIELD_BITPOS (field)) != INTEGER_CST)
- goto record_lose;
-
- bitpos = TREE_INT_CST_LOW (DECL_FIELD_BITPOS (field));
-
- /* Must be BLKmode if any field crosses a word boundary,
- since extract_bit_field can't handle that in registers. */
- if (bitpos / BITS_PER_WORD
- != ((TREE_INT_CST_LOW (DECL_SIZE (field)) + bitpos - 1)
- / BITS_PER_WORD)
- /* But there is no problem if the field is entire words. */
- && TREE_INT_CST_LOW (DECL_SIZE (field)) % BITS_PER_WORD != 0)
- goto record_lose;
-
- /* If this field is the whole struct, remember its mode so
- that, say, we can put a double in a class into a DF
- register instead of forcing it to live in the stack. */
- if (simple_cst_equal (TYPE_SIZE (type), DECL_SIZE (field)))
- mode = DECL_MODE (field);
-
-#ifdef STRUCT_FORCE_BLK
- /* With some targets, eg. c4x, it is sub-optimal
- to access an aligned BLKmode structure as a scalar. */
- if (mode == VOIDmode && STRUCT_FORCE_BLK (field))
- goto record_lose;
-#endif /* STRUCT_FORCE_BLK */
- }
-
- if (mode != VOIDmode)
- /* We only have one real field; use its mode. */
- TYPE_MODE (type) = mode;
- else
- TYPE_MODE (type)
- = mode_for_size (TREE_INT_CST_LOW (TYPE_SIZE (type)),
- MODE_INT, 1);
-
- /* If structure's known alignment is less than
- what the scalar mode would need, and it matters,
- then stick with BLKmode. */
- if (STRICT_ALIGNMENT
- && ! (TYPE_ALIGN (type) >= BIGGEST_ALIGNMENT
- || ((int) TYPE_ALIGN (type)
- >= TREE_INT_CST_LOW (TYPE_SIZE (type)))))
- {
- if (TYPE_MODE (type) != BLKmode)
- /* If this is the only reason this type is BLKmode,
- then don't force containing types to be BLKmode. */
- TYPE_NO_FORCE_BLK (type) = 1;
- TYPE_MODE (type) = BLKmode;
- }
-
- record_lose: ;
- }
-
- /* Lay out any static members. This is done now
- because their type may use the record's type. */
- while (pending_statics)
- {
- layout_decl (TREE_VALUE (pending_statics), 0);
- pending_statics = TREE_CHAIN (pending_statics);
- }
- break;
-
case UNION_TYPE:
case QUAL_UNION_TYPE:
- layout_union (type);
- TYPE_MODE (type) = BLKmode;
- if (TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST
- /* If structure's known alignment is less than
- what the scalar mode would need, and it matters,
- then stick with BLKmode. */
- && (! STRICT_ALIGNMENT
- || TYPE_ALIGN (type) >= BIGGEST_ALIGNMENT
- || ((int) TYPE_ALIGN (type)
- >= TREE_INT_CST_LOW (TYPE_SIZE (type)))))
- {
- tree field;
+ {
+ tree field;
+ record_layout_info rli;
- /* A union which has any BLKmode members must itself be BLKmode;
- it can't go in a register.
- Unless the member is BLKmode only because it isn't aligned. */
- for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
- {
- if (TREE_CODE (field) != FIELD_DECL)
- continue;
+ /* Initialize the layout information. */
+ rli = start_record_layout (type);
- if (TYPE_MODE (TREE_TYPE (field)) == BLKmode
- && ! TYPE_NO_FORCE_BLK (TREE_TYPE (field)))
- goto union_lose;
- }
+ /* If this is a QUAL_UNION_TYPE, we want to process the fields
+ in the reverse order in building the COND_EXPR that denotes
+ its size. We reverse them again later. */
+ if (TREE_CODE (type) == QUAL_UNION_TYPE)
+ TYPE_FIELDS (type) = nreverse (TYPE_FIELDS (type));
- TYPE_MODE (type)
- = mode_for_size (TREE_INT_CST_LOW (TYPE_SIZE (type)),
- MODE_INT, 1);
+ /* Place all the fields. */
+ for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
+ place_field (rli, field);
- union_lose: ;
- }
+ if (TREE_CODE (type) == QUAL_UNION_TYPE)
+ TYPE_FIELDS (type) = nreverse (TYPE_FIELDS (type));
+
+ /* Finish laying out the record. */
+ finish_record_layout (rli);
+ }
break;
case SET_TYPE: /* Used by Chill and Pascal. */
abort ();
}
- /* Normally, use the alignment corresponding to the mode chosen.
- However, where strict alignment is not required, avoid
- over-aligning structures, since most compilers do not do this
- alignment. */
-
- if (TYPE_MODE (type) != BLKmode && TYPE_MODE (type) != VOIDmode
- && (STRICT_ALIGNMENT
- || (TREE_CODE (type) != RECORD_TYPE && TREE_CODE (type) != UNION_TYPE
- && TREE_CODE (type) != QUAL_UNION_TYPE
- && TREE_CODE (type) != ARRAY_TYPE)))
- TYPE_ALIGN (type) = GET_MODE_ALIGNMENT (TYPE_MODE (type));
-
- /* Do machine-dependent extra alignment. */
-#ifdef ROUND_TYPE_ALIGN
- TYPE_ALIGN (type)
- = ROUND_TYPE_ALIGN (type, TYPE_ALIGN (type), BITS_PER_UNIT);
-#endif
-
-#ifdef ROUND_TYPE_SIZE
- if (TYPE_SIZE (type) != 0)
- TYPE_SIZE (type)
- = ROUND_TYPE_SIZE (type, TYPE_SIZE (type), TYPE_ALIGN (type));
-#endif
-
- /* Evaluate nonconstant size only once, either now or as soon as safe. */
- if (TYPE_SIZE (type) != 0 && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
- TYPE_SIZE (type) = variable_size (TYPE_SIZE (type));
-
- /* If we failed to find a simple way to calculate the unit size
- of the type above, find it by division. */
- if (TYPE_SIZE_UNIT (type) == 0 && TYPE_SIZE (type) != 0)
- /* TYPE_SIZE (type) is computed in bitsizetype. After the division, the
- result will fit in sizetype. We will get more efficient code using
- sizetype, so we force a conversion. */
- TYPE_SIZE_UNIT (type)
- = convert (sizetype,
- size_binop (FLOOR_DIV_EXPR, TYPE_SIZE (type),
- bitsize_int (BITS_PER_UNIT)));
-
- /* Once again evaluate only once, either now or as soon as safe. */
- if (TYPE_SIZE_UNIT (type) != 0
- && TREE_CODE (TYPE_SIZE_UNIT (type)) != INTEGER_CST)
- TYPE_SIZE_UNIT (type) = variable_size (TYPE_SIZE_UNIT (type));
+ /* Compute the final TYPE_SIZE, TYPE_ALIGN, etc. for TYPE. For
+ records and unions, finish_record_layout already called this
+ function. */
+ if (TREE_CODE (type) != RECORD_TYPE
+ && TREE_CODE (type) != UNION_TYPE
+ && TREE_CODE (type) != QUAL_UNION_TYPE)
+ finalize_type_size (type);
- /* Also layout any other variants of the type. */
- if (TYPE_NEXT_VARIANT (type)
- || type != TYPE_MAIN_VARIANT (type))
- {
- tree variant;
- /* Record layout info of this variant. */
- tree size = TYPE_SIZE (type);
- tree size_unit = TYPE_SIZE_UNIT (type);
- unsigned int align = TYPE_ALIGN (type);
- enum machine_mode mode = TYPE_MODE (type);
-
- /* Copy it into all variants. */
- for (variant = TYPE_MAIN_VARIANT (type);
- variant != 0;
- variant = TYPE_NEXT_VARIANT (variant))
- {
- TYPE_SIZE (variant) = size;
- TYPE_SIZE_UNIT (variant) = size_unit;
- TYPE_ALIGN (variant) = align;
- TYPE_MODE (variant) = mode;
- }
- }
-
pop_obstacks ();
resume_momentary (old);
/* If this type is created before sizetype has been permanently set,
record it so set_sizetype can fix it up. */
if (! sizetype_set)
- {
- TREE_CHAIN (type) = early_type_list;
- early_type_list = type;
- }
+ early_type_list = tree_cons (NULL_TREE, type, early_type_list);
}
\f
/* Create and return a type for signed integers of PRECISION bits. */
TREE_UNSIGNED (t) = 1;
TYPE_PRECISION (t) = GET_MODE_BITSIZE (SImode);
TYPE_MIN_VALUE (t) = build_int_2 (0, 0);
+ TYPE_IS_SIZETYPE (t) = 1;
/* 1000 avoids problems with possible overflow and is certainly
larger than any size value we'd want to be storing. */
int precision = MIN (oprecision + BITS_PER_UNIT_LOG + 1,
2 * HOST_BITS_PER_WIDE_INT);
unsigned int i;
- tree t, next;
+ tree t;
if (sizetype_set)
abort ();
/* Make copies of nodes since we'll be setting TYPE_IS_SIZETYPE. */
sizetype = copy_node (type);
+ TYPE_DOMAIN (sizetype) = type;
+ TYPE_IS_SIZETYPE (sizetype) = 1;
bitsizetype = make_node (INTEGER_TYPE);
TYPE_NAME (bitsizetype) = TYPE_NAME (type);
TYPE_PRECISION (bitsizetype) = precision;
+ TYPE_IS_SIZETYPE (bitsizetype) = 1;
if (TREE_UNSIGNED (type))
fixup_unsigned_type (bitsizetype);
TYPE_NAME (bitsizetype) = get_identifier ("bit_size_type");
+ /* Show is a sizetype, is a main type, and has no pointers to it. */
for (i = 0; i < sizeof sizetype_tab / sizeof sizetype_tab[0]; i++)
- TYPE_IS_SIZETYPE (sizetype_tab[i]) = 1;
+ {
+ TYPE_IS_SIZETYPE (sizetype_tab[i]) = 1;
+ TYPE_MAIN_VARIANT (sizetype_tab[i]) = sizetype_tab[i];
+ TYPE_NEXT_VARIANT (sizetype_tab[i]) = 0;
+ TYPE_POINTER_TO (sizetype_tab[i]) = 0;
+ TYPE_REFERENCE_TO (sizetype_tab[i]) = 0;
+ }
ggc_add_tree_root ((tree *) &sizetype_tab,
sizeof sizetype_tab / sizeof (tree));
/* Go down each of the types we already made and set the proper type
for the sizes in them. */
- for (t = early_type_list; t != 0; t = next)
+ for (t = early_type_list; t != 0; t = TREE_CHAIN (t))
{
- next = TREE_CHAIN (t);
- TREE_CHAIN (t) = 0;
-
- if (TREE_CODE (t) != INTEGER_TYPE)
+ if (TREE_CODE (TREE_VALUE (t)) != INTEGER_TYPE)
abort ();
- TREE_TYPE (TYPE_SIZE (t)) = bitsizetype;
- TREE_TYPE (TYPE_SIZE_UNIT (t)) = sizetype;
+ TREE_TYPE (TYPE_SIZE (TREE_VALUE (t))) = bitsizetype;
+ TREE_TYPE (TYPE_SIZE_UNIT (TREE_VALUE (t))) = sizetype;
}
early_type_list = 0;
int volatilep;
{
enum machine_mode mode;
- int unit = 0;
+ unsigned int unit = 0;
/* Find the narrowest integer mode that contains the bit field. */
for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT); mode != VOIDmode;
if the extra 4th byte is past the end of memory.
(Though at least one Unix compiler ignores this problem:
that on the Sequent 386 machine. */
- || MIN (unit, BIGGEST_ALIGNMENT) > (int) align
+ || MIN (unit, BIGGEST_ALIGNMENT) > align
|| (largest_mode != VOIDmode && unit > GET_MODE_BITSIZE (largest_mode)))
return VOIDmode;
unit = GET_MODE_BITSIZE (tmode);
if (bitpos / unit == (bitpos + bitsize - 1) / unit
&& unit <= BITS_PER_WORD
- && unit <= (int) MIN (align, BIGGEST_ALIGNMENT)
+ && unit <= MIN (align, BIGGEST_ALIGNMENT)
&& (largest_mode == VOIDmode
|| unit <= GET_MODE_BITSIZE (largest_mode)))
wide_mode = tmode;
get_mode_alignment (mode)
enum machine_mode mode;
{
- unsigned alignment = GET_MODE_UNIT_SIZE (mode);
+ unsigned int alignment = GET_MODE_UNIT_SIZE (mode) * BITS_PER_UNIT;
/* Extract the LSB of the size. */
alignment = alignment & -alignment;
-
- alignment *= BITS_PER_UNIT;
alignment = MIN (BIGGEST_ALIGNMENT, MAX (1, alignment));
return alignment;
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