/* C-compiler utilities for types and variables storage layout
Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1996, 1998,
- 1999, 2000, 2001, 2002 Free Software Foundation, Inc.
+ 1999, 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
This file is part of GCC.
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));
+#if defined (PCC_BITFIELD_TYPE_MATTERS) || defined (BITFIELD_NBYTES_LIMITED)
static int excess_unit_span PARAMS ((HOST_WIDE_INT, HOST_WIDE_INT,
HOST_WIDE_INT, HOST_WIDE_INT,
tree));
+#endif
static unsigned int update_alignment_for_field
PARAMS ((record_layout_info, tree,
unsigned int));
variable_size (size)
tree size;
{
+ tree save;
+
/* If the language-processor is to take responsibility for variable-sized
items (e.g., languages which have elaboration procedures like Ada),
just return SIZE unchanged. Likewise for self-referential sizes and
|| contains_placeholder_p (size))
return size;
- size = save_expr (size);
+ if (TREE_CODE (size) == MINUS_EXPR && integer_onep (TREE_OPERAND (size, 1)))
+ /* If this is the upper bound of a C array, leave the minus 1 outside
+ the SAVE_EXPR so it can be folded away. */
+ TREE_OPERAND (size, 0) = save = save_expr (TREE_OPERAND (size, 0));
+ else
+ size = save = save_expr (size);
/* If an array with a variable number of elements is declared, and
the elements require destruction, we will emit a cleanup for the
`unsaved', i.e., all SAVE_EXPRs are recalculated. However, we do
not wish to do that here; the array-size is the same in both
places. */
- if (TREE_CODE (size) == SAVE_EXPR)
- SAVE_EXPR_PERSISTENT_P (size) = 1;
+ if (TREE_CODE (save) == SAVE_EXPR)
+ SAVE_EXPR_PERSISTENT_P (save) = 1;
if ((*lang_hooks.decls.global_bindings_p) ())
{
}
if (immediate_size_expand)
- /* NULL_RTX is not defined; neither is the rtx type.
- Also, we would like to pass const0_rtx here, but don't have it. */
- expand_expr (size, expand_expr (integer_zero_node, NULL_RTX, VOIDmode, 0),
- VOIDmode, 0);
+ expand_expr (save, const0_rtx, VOIDmode, 0);
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. */
;
else
- put_pending_size (size);
+ put_pending_size (save);
return size;
}
return mode;
}
+/* Return the alignment of MODE. This will be bounded by 1 and
+ BIGGEST_ALIGNMENT. */
+
+unsigned int
+get_mode_alignment (mode)
+ enum machine_mode mode;
+{
+ unsigned int alignment;
+
+ if (GET_MODE_CLASS (mode) == MODE_COMPLEX_FLOAT
+ || GET_MODE_CLASS (mode) == MODE_COMPLEX_INT)
+ alignment = GET_MODE_UNIT_SIZE (mode);
+ else
+ alignment = GET_MODE_SIZE (mode);
+
+ /* Extract the LSB of the size. */
+ alignment = alignment & -alignment;
+ alignment *= BITS_PER_UNIT;
+
+ alignment = MIN (BIGGEST_ALIGNMENT, MAX (1, alignment));
+ return alignment;
+}
+
/* Return the value of VALUE, rounded up to a multiple of DIVISOR.
This can only be applied to objects of a sizetype. */
#ifdef STRUCTURE_SIZE_BOUNDARY
/* Packed structures don't need to have minimum size. */
if (! TYPE_PACKED (t))
- rli->record_align = MAX (rli->record_align, STRUCTURE_SIZE_BOUNDARY);
+ rli->record_align = MAX (rli->record_align, (unsigned) STRUCTURE_SIZE_BOUNDARY);
#endif
rli->offset = size_zero_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. */
+ /* A zero-length bit-field affects the alignment of the next
+ field. */
+ if (!DECL_PACKED (field) && integer_zerop (DECL_SIZE (field)))
+ {
+ desired_align = TYPE_ALIGN (type);
+#ifdef ADJUST_FIELD_ALIGN
+ desired_align = ADJUST_FIELD_ALIGN (field, desired_align);
+#endif
+ }
+
+ /* Named bit-fields cause the entire structure to have the
+ alignment implied by their type. */
if (DECL_NAME (field) != 0)
{
unsigned int type_align = TYPE_ALIGN (type);
else if (DECL_PACKED (field))
type_align = MIN (type_align, BITS_PER_UNIT);
+ /* The alignment of the record is increased to the maximum
+ of the current alignment, the alignment indicated on the
+ field (i.e., the alignment specified by an __aligned__
+ attribute), and the alignment indicated by the type of
+ the field. */
+ rli->record_align = MAX (rli->record_align, desired_align);
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));
DECL_SIZE_UNIT (field), rli->offset));
}
+#if defined (PCC_BITFIELD_TYPE_MATTERS) || defined (BITFIELD_NBYTES_LIMITED)
/* A bitfield of SIZE with a required access alignment of ALIGN is allocated
at BYTE_OFFSET / BIT_OFFSET. Return nonzero if the field would span more
units of alignment than the underlying TYPE. */
> ((unsigned HOST_WIDE_INT) tree_low_cst (TYPE_SIZE (type), 1)
/ align));
}
+#endif
/* RLI contains information about the layout of a RECORD_TYPE. FIELD
is a FIELD_DECL to be added after those fields already present in
used in the record, and any additional adjacent long bitfields are
packed into the same chunk of 32 bits. However, if the size
changes, a new field of that size is allocated.) In an unpacked
- record, this is the same as using alignment, but not eqivalent
+ record, this is the same as using alignment, but not equivalent
when packing.
- Note: for compatability, we use the type size, not the type alignment
+ Note: for compatibility, we use the type size, not the type alignment
to determine alignment, since that matches the documentation */
if ((* targetm.ms_bitfield_layout_p) (rli->t)
TYPE_SIZE (TREE_TYPE (prev_saved)))
: !integer_zerop (DECL_SIZE (field)) ))
{
- unsigned int type_align = 8; /* Never below 8 for compatability */
+ unsigned int type_align = 8; /* Never below 8 for compatibility */
/* (When not a bitfield), we could be seeing a flex array (with
no DECL_SIZE). Since we won't be using remaining_in_alignment
/* 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. */
+ indicated by RLI. */
static void
finalize_record_size (rli)
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 (rli->t) && TREE_VEC_LENGTH (TYPE_BINFO (rli->t)) > 6)
- {
- TYPE_BINFO_SIZE (rli->t) = unpadded_size;
- TYPE_BINFO_SIZE_UNIT (rli->t) = unpadded_size_unit;
- }
-
- /* Round the size up to be a multiple of the required alignment */
+ /* Round the size up to be a multiple of the required alignment */
#ifdef ROUND_TYPE_SIZE
TYPE_SIZE (rli->t) = ROUND_TYPE_SIZE (rli->t, unpadded_size,
TYPE_ALIGN (rli->t));
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