/* C-compiler utilities for types and variables storage layout
- Copyright (C) 1987, 88, 92-97, 1998 Free Software Foundation, Inc.
+ Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1996, 1998,
+ 1999, 2000, 2001 Free Software Foundation, Inc.
This file is part of GNU CC.
#include "config.h"
#include "system.h"
-
#include "tree.h"
#include "rtl.h"
+#include "tm_p.h"
#include "flags.h"
#include "function.h"
#include "expr.h"
#include "toplev.h"
#include "ggc.h"
-#define CEIL(x,y) (((x) + (y) - 1) / (y))
+/* Set to one when set_sizetype has been called. */
+static int sizetype_set;
+
+/* List of types created before set_sizetype has been called. We do not
+ make this a GGC root since we want these nodes to be reclaimed. */
+static tree early_type_list;
/* Data type for the expressions representing sizes of data types.
It is the first integer type laid out. */
-
-struct sizetype_tab sizetype_tab;
-
-/* An integer constant with value 0 whose type is sizetype. */
-
-tree size_zero_node;
-
-/* An integer constant with value 1 whose type is sizetype. */
-
-tree size_one_node;
+tree sizetype_tab[(int) TYPE_KIND_LAST];
/* If nonzero, this is an upper limit on alignment of structure fields.
The value is measured in bits. */
-int maximum_field_alignment;
+unsigned int maximum_field_alignment;
/* If non-zero, the alignment of a bitstring or (power-)set value, in bits.
May be overridden by front-ends. */
-int set_alignment = 0;
+unsigned int set_alignment = 0;
+
+/* Nonzero if all REFERENCE_TYPEs are internal and hence should be
+ allocated in Pmode, not ptr_mode. Set only by internal_reference_types
+ called only by a front end. */
+static int reference_types_internal = 0;
-static tree layout_record PROTO((tree));
-static void layout_union PROTO((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));
+extern void debug_rli PARAMS ((record_layout_info));
\f
/* SAVE_EXPRs for sizes of types and decls, waiting to be expanded. */
int immediate_size_expand;
+/* Show that REFERENCE_TYPES are internal and should be Pmode. Called only
+ by front end. */
+
+void
+internal_reference_types ()
+{
+ reference_types_internal = 1;
+}
+
+/* Get a list of all the objects put on the pending sizes list. */
+
tree
get_pending_sizes ()
{
/* Put each SAVE_EXPR into the current function. */
for (t = chain; t; t = TREE_CHAIN (t))
SAVE_EXPR_CONTEXT (TREE_VALUE (t)) = current_function_decl;
+
pending_sizes = 0;
return chain;
}
+/* Return non-zero if EXPR is present on the pending sizes list. */
+
+int
+is_pending_size (expr)
+ tree expr;
+{
+ tree t;
+
+ for (t = pending_sizes; t; t = TREE_CHAIN (t))
+ if (TREE_VALUE (t) == expr)
+ return 1;
+ return 0;
+}
+
+/* Add EXPR to the pending sizes list. */
+
+void
+put_pending_size (expr)
+ tree expr;
+{
+ if (TREE_CODE (expr) == SAVE_EXPR)
+ pending_sizes = tree_cons (NULL_TREE, expr, pending_sizes);
+}
+
+/* Put a chain of objects into the pending sizes list, which must be
+ empty. */
+
void
put_pending_sizes (chain)
tree chain;
size = 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
+ array. That cleanup is run both on normal exit from the block
+ and in the exception-handler for the block. Normally, when code
+ is used in both ordinary code and in an exception handler it is
+ `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 (global_bindings_p ())
{
if (TREE_CONSTANT (size))
else
error ("variable-size type declared outside of any function");
- return size_int (1);
+ return size_one_node;
}
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_PTR, VOIDmode, 0),
+ expand_expr (size, expand_expr (integer_zero_node, NULL_RTX, VOIDmode, 0),
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
- pending_sizes = tree_cons (NULL_TREE, size, pending_sizes);
+ put_pending_size (size);
return size;
}
{
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_COMPLEX_INT:
case MODE_COMPLEX_FLOAT:
case MODE_FLOAT:
+ case MODE_VECTOR_INT:
+ case MODE_VECTOR_FLOAT:
mode = mode_for_size (GET_MODE_BITSIZE (mode), MODE_INT, 0);
break;
case MODE_RANDOM:
if (mode == BLKmode)
break;
- /* FALLTHRU */
+
+ /* ... fall through ... */
case MODE_CC:
default:
- abort();
+ abort ();
}
return mode;
}
-/* Return the value of VALUE, rounded up to a multiple of DIVISOR. */
+/* Return the value of VALUE, rounded up to a multiple of DIVISOR.
+ This can only be applied to objects of a sizetype. */
tree
round_up (value, divisor)
tree value;
int divisor;
{
- return size_binop (MULT_EXPR,
- size_binop (CEIL_DIV_EXPR, value, size_int (divisor)),
- size_int (divisor));
+ tree arg = size_int_type (divisor, TREE_TYPE (value));
+
+ return size_binop (MULT_EXPR, size_binop (CEIL_DIV_EXPR, value, arg), arg);
+}
+
+/* Likewise, but round down. */
+
+tree
+round_down (value, divisor)
+ tree value;
+ int divisor;
+{
+ tree arg = size_int_type (divisor, TREE_TYPE (value));
+
+ return size_binop (MULT_EXPR, size_binop (FLOOR_DIV_EXPR, value, arg), arg);
}
\f
/* Set the size, mode and alignment of a ..._DECL node.
void
layout_decl (decl, known_align)
tree decl;
- unsigned known_align;
+ unsigned int known_align;
{
register tree type = TREE_TYPE (decl);
register enum tree_code code = TREE_CODE (decl);
- int spec_size = DECL_FIELD_SIZE (decl);
if (code == CONST_DECL)
return;
-
- if (code != VAR_DECL && code != PARM_DECL && code != RESULT_DECL
- && code != FIELD_DECL && code != TYPE_DECL)
+ else if (code != VAR_DECL && code != PARM_DECL && code != RESULT_DECL
+ && code != TYPE_DECL && code != FIELD_DECL)
abort ();
if (type == error_mark_node)
- {
- type = void_type_node;
- spec_size = 0;
- }
-
- /* Usually the size and mode come from the data type without change. */
+ type = void_type_node;
+
+ /* 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. */
- DECL_MODE (decl) = TYPE_MODE (type);
TREE_UNSIGNED (decl) = TREE_UNSIGNED (type);
- if (DECL_SIZE (decl) == 0)
- DECL_SIZE (decl) = TYPE_SIZE (type);
+ if (DECL_MODE (decl) == VOIDmode)
+ DECL_MODE (decl) = TYPE_MODE (type);
- if (code == FIELD_DECL && DECL_BIT_FIELD (decl))
+ if (DECL_SIZE (decl) == 0)
{
- if (spec_size == 0 && DECL_NAME (decl) != 0)
- abort ();
-
- /* Size is specified number of bits. */
- DECL_SIZE (decl) = size_int (spec_size);
+ DECL_SIZE (decl) = TYPE_SIZE (type);
+ DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (type);
}
+ 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. */
- else if (DECL_ALIGN (decl) == 0
- || (! DECL_PACKED (decl) && TYPE_ALIGN (type) > DECL_ALIGN (decl)))
- DECL_ALIGN (decl) = TYPE_ALIGN (type);
+ if (! (code == FIELD_DECL && DECL_BIT_FIELD (decl))
+ && (DECL_ALIGN (decl) == 0
+ || (! (code == FIELD_DECL && DECL_PACKED (decl))
+ && TYPE_ALIGN (type) > DECL_ALIGN (decl))))
+ {
+ DECL_ALIGN (decl) = TYPE_ALIGN (type);
+ DECL_USER_ALIGN (decl) = TYPE_USER_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;
if (maximum_field_alignment != 0)
- DECL_ALIGN (decl) = MIN (DECL_ALIGN (decl),
- (unsigned)maximum_field_alignment);
+ DECL_ALIGN (decl) = MIN (DECL_ALIGN (decl), maximum_field_alignment);
else if (DECL_PACKED (decl))
- DECL_ALIGN (decl) = MIN (DECL_ALIGN (decl), BITS_PER_UNIT);
+ {
+ DECL_ALIGN (decl) = MIN (DECL_ALIGN (decl), BITS_PER_UNIT);
+ DECL_USER_ALIGN (decl) = 0;
+ }
}
- 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 ((unsigned) GET_MODE_ALIGNMENT (xmode),
+ DECL_ALIGN (decl) = MAX (GET_MODE_ALIGNMENT (xmode),
DECL_ALIGN (decl));
DECL_MODE (decl) = xmode;
- DECL_SIZE (decl) = size_int (GET_MODE_BITSIZE (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 (decl) != 0
- && (TREE_CODE (DECL_SIZE (decl)) != INTEGER_CST
- || (TREE_INT_CST_LOW (DECL_SIZE (decl)) % BITS_PER_UNIT) == 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 (DECL_SIZE (decl) != 0 && TREE_CODE (DECL_SIZE (decl)) != INTEGER_CST)
DECL_SIZE (decl) = variable_size (DECL_SIZE (decl));
+ if (DECL_SIZE_UNIT (decl) != 0
+ && TREE_CODE (DECL_SIZE_UNIT (decl)) != INTEGER_CST)
+ DECL_SIZE_UNIT (decl) = variable_size (DECL_SIZE_UNIT (decl));
+
+ /* If requested, warn about definitions of large data objects. */
+ if (warn_larger_than
+ && (code == VAR_DECL || code == PARM_DECL)
+ && ! DECL_EXTERNAL (decl))
+ {
+ tree size = DECL_SIZE_UNIT (decl);
+
+ if (size != 0 && TREE_CODE (size) == INTEGER_CST
+ && compare_tree_int (size, larger_than_size) > 0)
+ {
+ unsigned int size_as_int = TREE_INT_CST_LOW (size);
+
+ 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",
+ larger_than_size);
+ }
+ }
}
\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_s));
- 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 record_align = MAX (BITS_PER_UNIT, TYPE_ALIGN (rec));
- /* 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. */
- register HOST_WIDE_INT const_size = 0;
- register tree var_size = 0;
- /* Once we start using VAR_SIZE, this is the maximum alignment
- that we know VAR_SIZE has. */
- register int var_align = BITS_PER_UNIT;
+ /* 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)
{
- register int known_align = var_size ? var_align : const_size;
- register int desired_align = 0;
+ 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;
- }
- /* 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;
+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);
+
+ 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");
+
+ if (rli->pending_statics)
+ {
+ fprintf (stderr, "pending statics:\n");
+ debug_tree (rli->pending_statics);
+ }
+}
+
+/* Given an RLI with a possibly-incremented BITPOS, adjust OFFSET and
+ BITPOS if necessary to keep BITPOS below OFFSET_ALIGN. */
+
+void
+normalize_rli (rli)
+ record_layout_info rli;
+{
+ normalize_offset (&rli->offset, &rli->bitpos, rli->offset_align);
+}
+
+/* Returns the size in bytes allocated so far. */
+
+tree
+rli_size_unit_so_far (rli)
+ record_layout_info rli;
+{
+ return byte_from_pos (rli->offset, rli->bitpos);
+}
+
+/* Returns the size in bits allocated so far. */
+
+tree
+rli_size_so_far (rli)
+ record_layout_info rli;
+{
+ return bit_from_pos (rli->offset, rli->bitpos);
+}
+
+/* Called from place_field to handle unions. */
+
+static void
+place_union_field (rli, field)
+ record_layout_info rli;
+ tree field;
+{
+ unsigned int desired_align;
+
+ layout_decl (field, 0);
+
+ DECL_FIELD_OFFSET (field) = size_zero_node;
+ DECL_FIELD_BIT_OFFSET (field) = bitsize_zero_node;
+ SET_DECL_OFFSET_ALIGN (field, BIGGEST_ALIGNMENT);
+
+ desired_align = DECL_ALIGN (field);
- /* 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);
+ /* Some targets (i.e. i386) limit union field alignment
+ to a lower boundary than alignment of variables unless
+ it was overridden by attribute aligned. */
+ if (! DECL_USER_ALIGN (field))
+ desired_align =
+ MIN (desired_align, (unsigned) BIGGEST_FIELD_ALIGNMENT);
#endif
-#ifdef ADJUST_FIELD_ALIGN
- desired_align = ADJUST_FIELD_ALIGN (field, desired_align);
+
+ /* Union must be at least as aligned as any field requires. */
+ rli->record_align = MAX (rli->record_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)));
#endif
- /* Record must have at least as much alignment as any field.
- Otherwise, the alignment of the field within the record
- is meaningless. */
+ /* 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));
+}
-#ifndef PCC_BITFIELD_TYPE_MATTERS
- record_align = MAX (record_align, desired_align);
-#else
- if (PCC_BITFIELD_TYPE_MATTERS && TREE_TYPE (field) != error_mark_node
- && DECL_BIT_FIELD_TYPE (field)
- && ! integer_zerop (TYPE_SIZE (TREE_TYPE (field))))
- {
- /* 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 ((int)record_align, desired_align);
- else if (! DECL_PACKED (field))
- desired_align = TYPE_ALIGN (TREE_TYPE (field));
- /* A named bit field of declared type `int'
- forces the entire structure to have `int' alignment. */
- if (DECL_NAME (field) != 0)
- {
- int type_align = TYPE_ALIGN (TREE_TYPE (field));
- 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);
+/* 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.) */
- record_align = MAX ((int)record_align, type_align);
- }
- }
- else
- record_align = MAX ((int)record_align, desired_align);
-#endif
+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;
+ unsigned int user_align;
+ /* The type of this field. */
+ tree type = TREE_TYPE (field);
+
+ if (TREE_CODE (field) == ERROR_MARK || TREE_CODE (type) == ERROR_MARK)
+ return;
+
+ /* 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;
+ }
- /* Does this field automatically have alignment it needs
- by virtue of the fields that precede it and the record's
- own alignment? */
+ /* 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;
- if (const_size % desired_align != 0
- || (var_align % desired_align != 0
- && var_size != 0))
- {
- /* No, we need to skip space before this field.
- Bump the cumulative size to multiple of field alignment. */
+ /* 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;
+ }
- if (var_size == 0
- || 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, 0L));
- const_size = 0;
- var_size = round_up (var_size, desired_align);
- var_align = MIN (var_align, desired_align);
- }
- }
+ /* 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);
+ user_align = DECL_USER_ALIGN (field);
+ layout_decl (field, known_align);
+ if (! DECL_PACKED (field))
+ {
+ desired_align = DECL_ALIGN (field);
+ user_align = DECL_USER_ALIGN (field);
+ }
-#ifdef PCC_BITFIELD_TYPE_MATTERS
- if (PCC_BITFIELD_TYPE_MATTERS
- && TREE_CODE (field) == FIELD_DECL
- && TREE_TYPE (field) != error_mark_node
- && DECL_BIT_FIELD_TYPE (field)
- && !DECL_PACKED (field)
- && maximum_field_alignment == 0
- && !integer_zerop (DECL_SIZE (field)))
- {
- int type_align = TYPE_ALIGN (TREE_TYPE (field));
- 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;
- }
+ /* Some targets (i.e. i386, VMS) limit struct field alignment
+ to a lower boundary than alignment of variables unless
+ it was overridden by attribute aligned. */
+#ifdef BIGGEST_FIELD_ALIGNMENT
+ if (! user_align)
+ desired_align
+ = MIN (desired_align, (unsigned) BIGGEST_FIELD_ALIGNMENT);
#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
- && TREE_TYPE (field) != error_mark_node
- && DECL_BIT_FIELD_TYPE (field)
- && !DECL_PACKED (field)
- && !integer_zerop (DECL_SIZE (field)))
+#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)
{
- int type_align = TYPE_ALIGN (TREE_TYPE (field));
- register tree dsize = DECL_SIZE (field);
- int field_size = TREE_INT_CST_LOW (dsize);
+ unsigned int type_align = TYPE_ALIGN (type);
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));
+ }
- /* Size so far becomes the position of this field. */
+ 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. */
- if (var_size && const_size)
- DECL_FIELD_BITPOS (field)
- = size_binop (PLUS_EXPR, var_size, bitsize_int (const_size, 0L));
- else if (var_size)
- DECL_FIELD_BITPOS (field) = var_size;
+ if (warn_padded)
+ warning_with_decl (field, "padding struct to align `%s'");
+
+ /* 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) = size_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 == 0)
- 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
+
+#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->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);
+
+ 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
- if (var_size == 0)
+ /* 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;
+ SET_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_CODE (DECL_SIZE_UNIT (field)) != INTEGER_CST
+ || TREE_CONSTANT_OVERFLOW (DECL_SIZE_UNIT (field)))
{
- TYPE_SIZE (rec) = size_int (const_size);
+ 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
{
- if (const_size)
- var_size
- = size_binop (PLUS_EXPR, var_size, bitsize_int (const_size, 0L));
- TYPE_SIZE (rec) = var_size;
+ 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
+ TYPE_USER_ALIGN (rli->t) = 1;
+
+ /* 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)
- TYPE_BINFO_SIZE (rec) = TYPE_SIZE (rec);
+ 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 */
#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, unpadded_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
- 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;
-{
- register tree field;
- unsigned union_align = BITS_PER_UNIT;
+ 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 && TREE_CODE (rli->t) == RECORD_TYPE
+ && TYPE_PACKED (rli->t) && ! rli->packed_maybe_necessary
+ && TREE_CONSTANT (unpadded_size))
+ {
+ tree unpacked_size;
- /* 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 int const_size = 0;
- register tree var_size = 0;
+#ifdef ROUND_TYPE_ALIGN
+ rli->unpacked_align
+ = ROUND_TYPE_ALIGN (rli->t, TYPE_ALIGN (rli->t), rli->unpacked_align);
+#else
+ rli->unpacked_align = MAX (TYPE_ALIGN (rli->t), rli->unpacked_align);
+#endif
-#ifdef STRUCTURE_SIZE_BOUNDARY
- /* Packed structures don't need to have minimum size. */
- if (! TYPE_PACKED (rec))
- union_align = STRUCTURE_SIZE_BOUNDARY;
+#ifdef ROUND_TYPE_SIZE
+ unpacked_size = ROUND_TYPE_SIZE (rli->t, TYPE_SIZE (rli->t),
+ rli->unpacked_align);
+#else
+ unpacked_size = round_up (TYPE_SIZE (rli->t), rli->unpacked_align);
#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 (simple_cst_equal (unpacked_size, TYPE_SIZE (rli->t)))
+ {
+ TYPE_PACKED (rli->t) = 0;
- for (field = TYPE_FIELDS (rec); field; field = TREE_CHAIN (field))
- {
- /* Enums which are local to this class need not be laid out. */
- if (TREE_CODE (field) == CONST_DECL || TREE_CODE (field) == TYPE_DECL)
- continue;
+ if (TYPE_NAME (rli->t))
+ {
+ const char *name;
+
+ if (TREE_CODE (TYPE_NAME (rli->t)) == IDENTIFIER_NODE)
+ name = IDENTIFIER_POINTER (TYPE_NAME (rli->t));
+ else
+ name = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (rli->t)));
- layout_decl (field, 0);
- DECL_FIELD_BITPOS (field) = bitsize_int (0L, 0L);
+ if (STRICT_ALIGNMENT)
+ warning ("packed attribute causes inefficient alignment for `%s'", name);
+ else
+ warning ("packed attribute is unnecessary for `%s'", name);
+ }
+ else
+ {
+ if (STRICT_ALIGNMENT)
+ warning ("packed attribute causes inefficient alignment");
+ else
+ warning ("packed attribute is unnecessary");
+ }
+ }
+ }
+}
- /* Union must be at least as aligned as any field requires. */
+/* Compute the TYPE_MODE for the TYPE (which is a RECORD_TYPE). */
- union_align = MAX (union_align, DECL_ALIGN (field));
+void
+compute_record_mode (type)
+ tree type;
+{
+ tree field;
+ enum machine_mode mode = VOIDmode;
-#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
+ /* 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;
- 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 (DECL_SIZE (field)) == INTEGER_CST)
- const_size
- = MAX (const_size, TREE_INT_CST_LOW (DECL_SIZE (field)));
- else if (var_size == 0)
- var_size = DECL_SIZE (field);
- else
- var_size = size_binop (MAX_EXPR, var_size, DECL_SIZE (field));
- }
- else if (TREE_CODE (rec) == QUAL_UNION_TYPE)
- var_size = fold (build (COND_EXPR, sizetype, DECL_QUALIFIER (field),
- DECL_SIZE (field),
- var_size ? var_size : bitsize_int (0L, 0L)));
- }
+ if (! host_integerp (TYPE_SIZE (type), 1))
+ return;
+
+ /* 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))
+ {
+ unsigned HOST_WIDE_INT bitpos;
+
+ if (TREE_CODE (field) != FIELD_DECL)
+ continue;
- if (TREE_CODE (rec) == QUAL_UNION_TYPE)
- TYPE_FIELDS (rec) = nreverse (TYPE_FIELDS (rec));
+ 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_low_cst (DECL_SIZE (field), 1) + 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 (simple_cst_equal (TYPE_SIZE (type), DECL_SIZE (field)))
+ mode = DECL_MODE (field);
+
+#ifdef MEMBER_TYPE_FORCES_BLK
+ /* With some targets, eg. c4x, it is sub-optimal
+ to access an aligned BLKmode structure as a scalar. */
+ if (mode == VOIDmode && MEMBER_TYPE_FORCES_BLK (field))
+ return;
+#endif /* MEMBER_TYPE_FORCES_BLK */
+ }
- /* 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, 0L);
- else if (const_size == 0)
- TYPE_SIZE (rec) = var_size;
+ /* If we only have one real field; use its mode. This only applies to
+ RECORD_TYPE. This does not apply to unions. */
+ if (TREE_CODE (type) == RECORD_TYPE && mode != VOIDmode)
+ TYPE_MODE (type) = mode;
else
- TYPE_SIZE (rec) = size_binop (MAX_EXPR, var_size,
- round_up (bitsize_int (const_size, 0L),
- BITS_PER_UNIT));
+ 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;
+ }
+}
- /* Determine the desired alignment. */
+/* Compute TYPE_SIZE and TYPE_ALIGN for TYPE, once it has been laid
+ out. */
+
+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. */
+
+ 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));
+ TYPE_USER_ALIGN (type) = 0;
+ }
+
+ /* 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);
+ unsigned int user_align = TYPE_USER_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_USER_ALIGN (variant) = user_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);
+
+ /* Perform any last tweaks to the TYPE_SIZE, etc. */
+ finalize_type_size (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);
+ }
+
+ /* Clean up. */
+ free (rli);
}
\f
/* Calculate the mode, size, and alignment for TYPE.
layout_type (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. */
- old = suspend_momentary ();
-
- /* Put all our nodes into the same obstack as the type. Also,
- make expressions saveable (this is a no-op for permanent types). */
-
- push_obstacks (TYPE_OBSTACK (type), TYPE_OBSTACK (type));
- saveable_allocation ();
-
switch (TREE_CODE (type))
{
case LANG_TYPE:
case BOOLEAN_TYPE: /* Used for Java, Pascal, and Chill. */
if (TYPE_PRECISION (type) == 0)
TYPE_PRECISION (type) = 1; /* default to one byte/boolean. */
+
/* ... fall through ... */
case INTEGER_TYPE:
TYPE_MODE (type) = smallest_mode_for_size (TYPE_PRECISION (type),
MODE_INT);
- TYPE_SIZE (type) = bitsize_int (GET_MODE_BITSIZE (TYPE_MODE (type)), 0L);
+ TYPE_SIZE (type) = bitsize_int (GET_MODE_BITSIZE (TYPE_MODE (type)));
TYPE_SIZE_UNIT (type) = size_int (GET_MODE_SIZE (TYPE_MODE (type)));
break;
case REAL_TYPE:
TYPE_MODE (type) = mode_for_size (TYPE_PRECISION (type), MODE_FLOAT, 0);
- TYPE_SIZE (type) = bitsize_int (GET_MODE_BITSIZE (TYPE_MODE (type)), 0L);
+ TYPE_SIZE (type) = bitsize_int (GET_MODE_BITSIZE (TYPE_MODE (type)));
TYPE_SIZE_UNIT (type) = size_int (GET_MODE_SIZE (TYPE_MODE (type)));
break;
(TREE_CODE (TREE_TYPE (type)) == INTEGER_TYPE
? MODE_COMPLEX_INT : MODE_COMPLEX_FLOAT),
0);
- TYPE_SIZE (type) = bitsize_int (GET_MODE_BITSIZE (TYPE_MODE (type)), 0L);
+ TYPE_SIZE (type) = bitsize_int (GET_MODE_BITSIZE (TYPE_MODE (type)));
TYPE_SIZE_UNIT (type) = size_int (GET_MODE_SIZE (TYPE_MODE (type)));
break;
+ case VECTOR_TYPE:
+ {
+ tree subtype;
+
+ subtype = TREE_TYPE (type);
+ TREE_UNSIGNED (type) = TREE_UNSIGNED (subtype);
+ TYPE_SIZE (type) = bitsize_int (GET_MODE_BITSIZE (TYPE_MODE (type)));
+ TYPE_SIZE_UNIT (type) = size_int (GET_MODE_SIZE (TYPE_MODE (type)));
+ }
+ 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_USER_ALIGN (type) = 0;
TYPE_MODE (type) = VOIDmode;
break;
case OFFSET_TYPE:
- TYPE_SIZE (type) = bitsize_int (POINTER_SIZE, 0L);
+ TYPE_SIZE (type) = bitsize_int (POINTER_SIZE);
TYPE_SIZE_UNIT (type) = size_int (POINTER_SIZE / BITS_PER_UNIT);
- TYPE_MODE (type) = ptr_mode;
+ /* A pointer might be MODE_PARTIAL_INT,
+ but ptrdiff_t must be integral. */
+ TYPE_MODE (type) = mode_for_size (POINTER_SIZE, MODE_INT, 0);
break;
case FUNCTION_TYPE:
case METHOD_TYPE:
TYPE_MODE (type) = mode_for_size (2 * POINTER_SIZE, MODE_INT, 0);
- TYPE_SIZE (type) = bitsize_int (2 * POINTER_SIZE, 0);
+ TYPE_SIZE (type) = bitsize_int (2 * POINTER_SIZE);
TYPE_SIZE_UNIT (type) = size_int ((2 * POINTER_SIZE) / BITS_PER_UNIT);
break;
case POINTER_TYPE:
case REFERENCE_TYPE:
- TYPE_MODE (type) = ptr_mode;
- TYPE_SIZE (type) = bitsize_int (POINTER_SIZE, 0L);
- TYPE_SIZE_UNIT (type) = size_int (POINTER_SIZE / BITS_PER_UNIT);
- TREE_UNSIGNED (type) = 1;
- TYPE_PRECISION (type) = POINTER_SIZE;
+ {
+ int nbits = ((TREE_CODE (type) == REFERENCE_TYPE
+ && reference_types_internal)
+ ? GET_MODE_BITSIZE (Pmode) : POINTER_SIZE);
+
+ TYPE_MODE (type) = nbits == POINTER_SIZE ? ptr_mode : Pmode;
+ TYPE_SIZE (type) = bitsize_int (nbits);
+ TYPE_SIZE_UNIT (type) = size_int (nbits / BITS_PER_UNIT);
+ TREE_UNSIGNED (type) = 1;
+ TYPE_PRECISION (type) = nbits;
+ }
break;
case ARRAY_TYPE:
tree length;
tree element_size;
- /* If UB is max (lb - 1, x), remove the MAX_EXPR since the
- test for negative below covers it. */
- if (TREE_CODE (ub) == MAX_EXPR
- && TREE_CODE (TREE_OPERAND (ub, 0)) == MINUS_EXPR
- && integer_onep (TREE_OPERAND (TREE_OPERAND (ub, 0), 1))
- && operand_equal_p (TREE_OPERAND (TREE_OPERAND (ub, 0), 0),
- lb, 0))
- ub = TREE_OPERAND (ub, 1);
- else if (TREE_CODE (ub) == MAX_EXPR
- && TREE_CODE (TREE_OPERAND (ub, 1)) == MINUS_EXPR
- && integer_onep (TREE_OPERAND (TREE_OPERAND (ub, 1), 1))
- && operand_equal_p (TREE_OPERAND (TREE_OPERAND (ub, 1),
- 0),
- lb, 0))
- ub = TREE_OPERAND (ub, 0);
-
/* The initial subtraction should happen in the original type so
that (possible) negative values are handled appropriately. */
length = size_binop (PLUS_EXPR, size_one_node,
- fold (build (MINUS_EXPR, TREE_TYPE (lb),
- ub, lb)));
-
- /* If neither bound is a constant and sizetype is signed, make
- sure the size is never negative. We should really do this
- if *either* bound is non-constant, but this is the best
- compromise between C and Ada. */
- if (! TREE_UNSIGNED (sizetype)
- && TREE_CODE (TYPE_MIN_VALUE (index)) != INTEGER_CST
- && TREE_CODE (TYPE_MAX_VALUE (index)) != INTEGER_CST)
- length = size_binop (MAX_EXPR, length, size_zero_node);
+ convert (sizetype,
+ fold (build (MINUS_EXPR,
+ TREE_TYPE (lb),
+ ub, lb))));
/* Special handling for arrays of bits (for Chill). */
element_size = TYPE_SIZE (element);
- if (TYPE_PACKED (type) && INTEGRAL_TYPE_P (element))
+ if (TYPE_PACKED (type) && INTEGRAL_TYPE_P (element)
+ && (integer_zerop (TYPE_MAX_VALUE (element))
+ || integer_onep (TYPE_MAX_VALUE (element)))
+ && host_integerp (TYPE_MIN_VALUE (element), 1))
{
- HOST_WIDE_INT maxvalue, minvalue;
- maxvalue = TREE_INT_CST_LOW (TYPE_MAX_VALUE (element));
- minvalue = TREE_INT_CST_LOW (TYPE_MIN_VALUE (element));
+ HOST_WIDE_INT maxvalue
+ = tree_low_cst (TYPE_MAX_VALUE (element), 1);
+ HOST_WIDE_INT minvalue
+ = tree_low_cst (TYPE_MIN_VALUE (element), 1);
+
if (maxvalue - minvalue == 1
&& (maxvalue == 1 || maxvalue == 0))
element_size = integer_one_node;
}
- TYPE_SIZE (type) = size_binop (MULT_EXPR, element_size, length);
+ TYPE_SIZE (type) = size_binop (MULT_EXPR, element_size,
+ convert (bitsizetype, length));
/* If we know the size of the element, calculate the total
size directly, rather than do some division thing below.
Note that we can't do this in the case where the size of
the elements is one bit since TYPE_SIZE_UNIT cannot be
set correctly in that case. */
- if (TYPE_SIZE_UNIT (element) != 0
- && element_size != integer_one_node)
- {
- TYPE_SIZE_UNIT (type)
- = size_binop (MULT_EXPR, TYPE_SIZE_UNIT (element), length);
- }
+ if (TYPE_SIZE_UNIT (element) != 0 && ! integer_onep (element_size))
+ TYPE_SIZE_UNIT (type)
+ = size_binop (MULT_EXPR, TYPE_SIZE_UNIT (element), length);
}
/* Now round the alignment and size,
#ifdef ROUND_TYPE_SIZE
if (TYPE_SIZE (type) != 0)
{
- tree tmp;
- tmp = ROUND_TYPE_SIZE (type, TYPE_SIZE (type), TYPE_ALIGN (type));
+ tree tmp
+ = ROUND_TYPE_SIZE (type, TYPE_SIZE (type), TYPE_ALIGN (type));
+
/* If the rounding changed the size of the type, remove any
pre-calculated TYPE_SIZE_UNIT. */
if (simple_cst_equal (TYPE_SIZE (type), tmp) != 1)
TYPE_SIZE_UNIT (type) = NULL;
+
TYPE_SIZE (type) = tmp;
}
#endif
TYPE_MODE (type) = BLKmode;
if (TYPE_SIZE (type) != 0
- && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST
+#ifdef MEMBER_TYPE_FORCES_BLK
+ && ! MEMBER_TYPE_FORCES_BLK (type)
+#endif
/* 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);
- }
-
- 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;
- /* 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;
+ {
+ tree field;
+ record_layout_info rli;
- if (TYPE_MODE (TREE_TYPE (field)) == BLKmode
- && ! TYPE_NO_FORCE_BLK (TREE_TYPE (field)))
- goto union_lose;
- }
+ /* Initialize the layout information. */
+ rli = start_record_layout (type);
- TYPE_MODE (type)
- = mode_for_size (TREE_INT_CST_LOW (TYPE_SIZE (type)),
- MODE_INT, 1);
+ /* 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));
- union_lose: ;
- }
+ /* Place all the fields. */
+ for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
+ place_field (rli, field);
+
+ 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. */
#ifndef SET_WORD_SIZE
#define SET_WORD_SIZE BITS_PER_WORD
#endif
- int alignment = set_alignment ? set_alignment : SET_WORD_SIZE;
+ unsigned int alignment
+ = set_alignment ? set_alignment : SET_WORD_SIZE;
int size_in_bits
= (TREE_INT_CST_LOW (TYPE_MAX_VALUE (TYPE_DOMAIN (type)))
- TREE_INT_CST_LOW (TYPE_MIN_VALUE (TYPE_DOMAIN (type))) + 1);
int rounded_size
= ((size_in_bits + alignment - 1) / alignment) * alignment;
- if (rounded_size > alignment)
+
+ if (rounded_size > (int) alignment)
TYPE_MODE (type) = BLKmode;
else
TYPE_MODE (type) = mode_for_size (alignment, MODE_INT, 1);
- TYPE_SIZE (type) = bitsize_int (rounded_size, 0L);
+
+ TYPE_SIZE (type) = bitsize_int (rounded_size);
TYPE_SIZE_UNIT (type) = size_int (rounded_size / BITS_PER_UNIT);
TYPE_ALIGN (type) = alignment;
+ TYPE_USER_ALIGN (type) = 0;
TYPE_PRECISION (type) = size_in_bits;
}
break;
/* The size may vary in different languages, so the language front end
should fill in the size. */
TYPE_ALIGN (type) = BIGGEST_ALIGNMENT;
+ TYPE_USER_ALIGN (type) = 0;
TYPE_MODE (type) = BLKmode;
break;
default:
abort ();
- } /* end switch */
-
- /* 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_UNIT (type) = size_binop (FLOOR_DIV_EXPR, TYPE_SIZE (type),
- size_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));
-
- /* 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);
- int align = TYPE_ALIGN (type);
- enum machine_mode mode = TYPE_MODE (type);
-
- /* Copy it into all variants. */
- for (variant = TYPE_MAIN_VARIANT (type);
- variant;
- 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);
+ /* 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);
+
+ /* If this type is created before sizetype has been permanently set,
+ record it so set_sizetype can fix it up. */
+ if (! sizetype_set)
+ early_type_list = tree_cons (NULL_TREE, type, early_type_list);
+
+ /* If an alias set has been set for this aggregate when it was incomplete,
+ force it into alias set 0.
+ This is too conservative, but we cannot call record_component_aliases
+ here because some frontends still change the aggregates after
+ layout_type. */
+ if (AGGREGATE_TYPE_P (type) && TYPE_ALIAS_SET_KNOWN_P (type))
+ TYPE_ALIAS_SET (type) = 0;
}
\f
/* Create and return a type for signed integers of PRECISION bits. */
TYPE_PRECISION (type) = precision;
- /* Create the extreme values based on the number of bits. */
-
- TYPE_MIN_VALUE (type)
- = build_int_2 ((precision - HOST_BITS_PER_WIDE_INT > 0
- ? 0 : (HOST_WIDE_INT) (-1) << (precision - 1)),
- (((HOST_WIDE_INT) (-1)
- << (precision - HOST_BITS_PER_WIDE_INT - 1 > 0
- ? precision - HOST_BITS_PER_WIDE_INT - 1
- : 0))));
- TYPE_MAX_VALUE (type)
- = build_int_2 ((precision - HOST_BITS_PER_WIDE_INT > 0
- ? -1 : ((HOST_WIDE_INT) 1 << (precision - 1)) - 1),
- (precision - HOST_BITS_PER_WIDE_INT - 1 > 0
- ? (((HOST_WIDE_INT) 1
- << (precision - HOST_BITS_PER_WIDE_INT - 1))) - 1
- : 0));
-
- /* Give this type's extreme values this type as their type. */
-
- TREE_TYPE (TYPE_MIN_VALUE (type)) = type;
- TREE_TYPE (TYPE_MAX_VALUE (type)) = type;
-
- /* The first type made with this or `make_unsigned_type'
- is the type for size values. */
-
- if (sizetype == 0)
- set_sizetype (type);
-
- /* Lay out the type: set its alignment, size, etc. */
-
- layout_type (type);
-
+ fixup_signed_type (type);
return type;
}
TYPE_PRECISION (type) = precision;
- /* The first type made with this or `make_signed_type'
- is the type for size values. */
-
- if (sizetype == 0)
- {
- TREE_UNSIGNED (type) = 1;
- set_sizetype (type);
- }
-
fixup_unsigned_type (type);
return type;
}
+\f
+/* Initialize sizetype and bitsizetype to a reasonable and temporary
+ value to enable integer types to be created. */
+
+void
+initialize_sizetypes ()
+{
+ tree t = make_node (INTEGER_TYPE);
+
+ /* Set this so we do something reasonable for the build_int_2 calls
+ below. */
+ integer_type_node = t;
+
+ TYPE_MODE (t) = SImode;
+ TYPE_ALIGN (t) = GET_MODE_ALIGNMENT (SImode);
+ TYPE_USER_ALIGN (t) = 0;
+ TYPE_SIZE (t) = build_int_2 (GET_MODE_BITSIZE (SImode), 0);
+ TYPE_SIZE_UNIT (t) = build_int_2 (GET_MODE_SIZE (SImode), 0);
+ 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. */
+ TYPE_MAX_VALUE (t) = build_int_2 (1000, 0);
+
+ /* These two must be different nodes because of the caching done in
+ size_int_wide. */
+ sizetype = t;
+ bitsizetype = copy_node (t);
+ integer_type_node = 0;
+}
/* Set sizetype to TYPE, and initialize *sizetype accordingly.
Also update the type of any standard type's sizes made so far. */
set_sizetype (type)
tree type;
{
- int oprecision = TYPE_PRECISION (type), precision;
+ int oprecision = TYPE_PRECISION (type);
+ /* The *bitsizetype types use a precision that avoids overflows when
+ calculating signed sizes / offsets in bits. However, when
+ cross-compiling from a 32 bit to a 64 bit host, we are limited to 64 bit
+ precision. */
+ int precision = MIN (oprecision + BITS_PER_UNIT_LOG + 1,
+ 2 * HOST_BITS_PER_WIDE_INT);
+ unsigned int i;
+ tree t;
- sizetype = type;
+ if (sizetype_set)
+ abort ();
- /* The *bitsizetype types use a precision that avoids overflows when
- calculating signed sizes / offsets in bits.
-
- We are allocating bitsizetype once and change it in place when
- we decide later that we want to change it. This way, we avoid the
- hassle of changing all the TYPE_SIZE (TREE_TYPE (sometype))
- individually in each front end. */
- if (! bitsizetype)
- bitsizetype = make_node (INTEGER_TYPE);
- if (TYPE_NAME (sizetype) && ! TYPE_NAME (bitsizetype))
- TYPE_NAME (bitsizetype) = TYPE_NAME (sizetype);
-
- precision = oprecision + BITS_PER_UNIT_LOG + 1;
- /* However, when cross-compiling from a 32 bit to a 64 bit host,
- we are limited to 64 bit precision. */
- if (precision > 2 * HOST_BITS_PER_WIDE_INT)
- precision = 2 * HOST_BITS_PER_WIDE_INT;
+ /* 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);
else
fixup_signed_type (bitsizetype);
+
layout_type (bitsizetype);
if (TREE_UNSIGNED (type))
{
usizetype = sizetype;
ubitsizetype = bitsizetype;
- ssizetype = make_signed_type (oprecision);
- sbitsizetype = make_signed_type (precision);
+ ssizetype = copy_node (make_signed_type (oprecision));
+ sbitsizetype = copy_node (make_signed_type (precision));
}
else
{
ssizetype = sizetype;
sbitsizetype = bitsizetype;
- usizetype = make_unsigned_type (oprecision);
- ubitsizetype = make_unsigned_type (precision);
+ usizetype = copy_node (make_unsigned_type (oprecision));
+ ubitsizetype = copy_node (make_unsigned_type (precision));
}
- ggc_add_tree_root ((tree*) &sizetype_tab, sizeof(sizetype_tab)/sizeof(tree));
-}
+ 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 < ARRAY_SIZE (sizetype_tab); i++)
+ {
+ 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 = TREE_CHAIN (t))
+ {
+ if (TREE_CODE (TREE_VALUE (t)) != INTEGER_TYPE)
+ abort ();
+
+ TREE_TYPE (TYPE_SIZE (TREE_VALUE (t))) = bitsizetype;
+ TREE_TYPE (TYPE_SIZE_UNIT (TREE_VALUE (t))) = sizetype;
+ }
+
+ early_type_list = 0;
+ sizetype_set = 1;
+}
+\f
/* Set the extreme values of TYPE based on its precision in bits,
then lay it out. Used when make_signed_type won't do
because the tree code is not INTEGER_TYPE.
TREE_TYPE (TYPE_MAX_VALUE (type)) = type;
/* Lay out the type: set its alignment, size, etc. */
-
layout_type (type);
}
TREE_TYPE (TYPE_MAX_VALUE (type)) = type;
/* Lay out the type: set its alignment, size, etc. */
-
layout_type (type);
}
\f
enum machine_mode
get_best_mode (bitsize, bitpos, align, largest_mode, volatilep)
int bitsize, bitpos;
- int align;
+ unsigned int align;
enum machine_mode largest_mode;
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;
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 = GET_MODE_UNIT_SIZE (mode) * BITS_PER_UNIT;
+
+ /* Extract the LSB of the size. */
+ alignment = alignment & -alignment;
+
+ alignment = MIN (BIGGEST_ALIGNMENT, MAX (1, alignment));
+ return alignment;
+}
+
/* This function is run once to initialize stor-layout.c. */
void
OSDN Git Service
