43577e6bd7
* Makefile.in (fold-const.o, stor-layout.o, stmt.o, sdbout.o, profile.o): Update. * c-common.c (c_common_nodes_and_builtins): Use pushdecl langhook. * c-common.h (gettags): Move here from tree.h. * c-tree.h (pushdecl, pushlevel, poplevel, set_block, insert_block, getdecls, kept_level_p, global_bindings_p): New. * dbxout.c (dbxout_init): Use getdecls langhook. * expr.c (expand_expr): Use insert_block langhook. * fold-const.c: Include langhooks.h. (fold_range_test, fold_binary_op_with_conditional_arg, fold): Use global_bindings_p langhook. * integrate.c (expand_inline_function): Use insert_block langhook. * langhooks-def.h (LANG_HOOKS_DECLS, LANG_HOOKS_PUSHLEVEL, LANG_HOOKS_POPLEVEL, LANG_HOOKS_GLOBAL_BINDINGS_P, LANG_HOOKS_INSERT_BLOCK, LANG_HOOKS_SET_BLOCK, LANG_HOOKS_PUSHDECL, LANG_HOOKS_GETDECLS): New. (LANG_HOOKS_INITIALIZER): Update. * langhooks.c (lhd_clear_binding_stack): Use global_bindings_p langhook. * langhooks.h (struct lang_hooks_for_decls): New. (struct lang_hooks): Update. * profile.c: Include langhooks.h. (output_func_start_profiler): Use new langhooks. * sdbout.c: Include langhooks.h. (sdbout_init, sdbout_finish): Use getdecls langhook. * stmt.c: Include langhooks.h. (expand_fixup, fixup_gotos): Use new langhooks. * stor-layout.c: Include langhooks.h. (variable_size): Use global_bindings_p langhook. * toplev.c (compile_file): Use getdecls langhook. * tree-inline.c (remap_block): Use insert_block langhook. * tree.h (pushdecl, pushlevel, poplevel, set_block, gettags, insert_block, getdecls, kept_level_p, global_bindings_p): Remove. cp: * cp-tree.h (pushdecl, pushlevel, poplevel, set_block, insert_block, getdecls, global_bindings_p): New. java: * cp-tree.h (pushdecl, pushlevel, poplevel, set_block, insert_block, getdecls, kept_level_p, global_bindings_p): New. f: * cp-tree.h (pushdecl, pushlevel, poplevel, set_block, insert_block, getdecls, global_bindings_p): New. From-SVN: r51136
1985 lines
62 KiB
C
1985 lines
62 KiB
C
/* 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.
|
||
|
||
This file is part of GCC.
|
||
|
||
GCC is free software; you can redistribute it and/or modify it under
|
||
the terms of the GNU General Public License as published by the Free
|
||
Software Foundation; either version 2, or (at your option) any later
|
||
version.
|
||
|
||
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
|
||
WARRANTY; without even the implied warranty of MERCHANTABILITY or
|
||
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
|
||
for more details.
|
||
|
||
You should have received a copy of the GNU General Public License
|
||
along with GCC; see the file COPYING. If not, write to the Free
|
||
Software Foundation, 59 Temple Place - Suite 330, Boston, MA
|
||
02111-1307, USA. */
|
||
|
||
|
||
#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"
|
||
#include "target.h"
|
||
#include "langhooks.h"
|
||
|
||
/* 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. */
|
||
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. */
|
||
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. */
|
||
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 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));
|
||
|
||
/* SAVE_EXPRs for sizes of types and decls, waiting to be expanded. */
|
||
|
||
static tree pending_sizes;
|
||
|
||
/* Nonzero means cannot safely call expand_expr now,
|
||
so put variable sizes onto `pending_sizes' instead. */
|
||
|
||
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 ()
|
||
{
|
||
tree chain = pending_sizes;
|
||
tree t;
|
||
|
||
/* 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;
|
||
{
|
||
/* Strip any simple arithmetic from EXPR to see if it has an underlying
|
||
SAVE_EXPR. */
|
||
while (TREE_CODE_CLASS (TREE_CODE (expr)) == '1'
|
||
|| (TREE_CODE_CLASS (TREE_CODE (expr)) == '2'
|
||
&& TREE_CONSTANT (TREE_OPERAND (expr, 1))))
|
||
expr = TREE_OPERAND (expr, 0);
|
||
|
||
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;
|
||
{
|
||
if (pending_sizes)
|
||
abort ();
|
||
|
||
pending_sizes = chain;
|
||
}
|
||
|
||
/* Given a size SIZE that may not be a constant, return a SAVE_EXPR
|
||
to serve as the actual size-expression for a type or decl. */
|
||
|
||
tree
|
||
variable_size (size)
|
||
tree size;
|
||
{
|
||
/* 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
|
||
constant sizes. */
|
||
if (TREE_CONSTANT (size)
|
||
|| (*lang_hooks.decls.global_bindings_p) () < 0
|
||
|| contains_placeholder_p (size))
|
||
return size;
|
||
|
||
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 ((*lang_hooks.decls.global_bindings_p) ())
|
||
{
|
||
if (TREE_CONSTANT (size))
|
||
error ("type size can't be explicitly evaluated");
|
||
else
|
||
error ("variable-size type declared outside of any function");
|
||
|
||
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_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
|
||
put_pending_size (size);
|
||
|
||
return size;
|
||
}
|
||
|
||
#ifndef MAX_FIXED_MODE_SIZE
|
||
#define MAX_FIXED_MODE_SIZE GET_MODE_BITSIZE (DImode)
|
||
#endif
|
||
|
||
/* Return the machine mode to use for a nonscalar of SIZE bits.
|
||
The mode must be in class CLASS, and have exactly that many bits.
|
||
If LIMIT is nonzero, modes of wider than MAX_FIXED_MODE_SIZE will not
|
||
be used. */
|
||
|
||
enum machine_mode
|
||
mode_for_size (size, class, limit)
|
||
unsigned int size;
|
||
enum mode_class class;
|
||
int limit;
|
||
{
|
||
enum machine_mode mode;
|
||
|
||
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 (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. */
|
||
|
||
enum machine_mode
|
||
smallest_mode_for_size (size, class)
|
||
unsigned int size;
|
||
enum mode_class class;
|
||
{
|
||
enum machine_mode mode;
|
||
|
||
/* Get the first mode which has at least this size, in the
|
||
specified class. */
|
||
for (mode = GET_CLASS_NARROWEST_MODE (class); mode != VOIDmode;
|
||
mode = GET_MODE_WIDER_MODE (mode))
|
||
if (GET_MODE_BITSIZE (mode) >= size)
|
||
return mode;
|
||
|
||
abort ();
|
||
}
|
||
|
||
/* Find an integer mode of the exact same size, or BLKmode on failure. */
|
||
|
||
enum machine_mode
|
||
int_mode_for_mode (mode)
|
||
enum machine_mode mode;
|
||
{
|
||
switch (GET_MODE_CLASS (mode))
|
||
{
|
||
case MODE_INT:
|
||
case MODE_PARTIAL_INT:
|
||
break;
|
||
|
||
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;
|
||
|
||
/* ... fall through ... */
|
||
|
||
case MODE_CC:
|
||
default:
|
||
abort ();
|
||
}
|
||
|
||
return mode;
|
||
}
|
||
|
||
/* 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;
|
||
{
|
||
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);
|
||
}
|
||
|
||
/* Set the size, mode and alignment of a ..._DECL node.
|
||
TYPE_DECL does need this for C++.
|
||
Note that LABEL_DECL and CONST_DECL nodes do not need this,
|
||
and FUNCTION_DECL nodes have them set up in a special (and simple) way.
|
||
Don't call layout_decl for them.
|
||
|
||
KNOWN_ALIGN is the amount of alignment we can assume this
|
||
decl has with no special effort. It is relevant only for FIELD_DECLs
|
||
and depends on the previous fields.
|
||
All that matters about KNOWN_ALIGN is which powers of 2 divide it.
|
||
If KNOWN_ALIGN is 0, it means, "as much alignment as you like":
|
||
the record will be aligned to suit. */
|
||
|
||
void
|
||
layout_decl (decl, known_align)
|
||
tree decl;
|
||
unsigned int known_align;
|
||
{
|
||
tree type = TREE_TYPE (decl);
|
||
enum tree_code code = TREE_CODE (decl);
|
||
|
||
if (code == CONST_DECL)
|
||
return;
|
||
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;
|
||
|
||
/* 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
|
||
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))
|
||
&& (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) = 0;
|
||
}
|
||
|
||
/* 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), maximum_field_alignment);
|
||
|
||
/* If the field is of variable size, we can't misalign it since we
|
||
have no way to make a temporary to align the result. But this
|
||
isn't an issue if the decl is not addressable. Likewise if it
|
||
is of unknown size. */
|
||
else if (DECL_PACKED (decl)
|
||
&& (DECL_NONADDRESSABLE_P (decl)
|
||
|| DECL_SIZE_UNIT (decl) == 0
|
||
|| TREE_CODE (DECL_SIZE_UNIT (decl)) == INTEGER_CST))
|
||
{
|
||
DECL_ALIGN (decl) = MIN (DECL_ALIGN (decl), BITS_PER_UNIT);
|
||
DECL_USER_ALIGN (decl) = 0;
|
||
}
|
||
}
|
||
|
||
/* 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)
|
||
{
|
||
enum machine_mode xmode
|
||
= mode_for_size_tree (DECL_SIZE (decl), MODE_INT, 1);
|
||
|
||
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_BIT_FIELD (decl) = 0;
|
||
}
|
||
}
|
||
|
||
/* Turn off DECL_BIT_FIELD if we won't need it set. */
|
||
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);
|
||
}
|
||
}
|
||
}
|
||
|
||
/* Hook for a front-end function that can modify the record layout as needed
|
||
immediately before it is finalized. */
|
||
|
||
void (*lang_adjust_rli) PARAMS ((record_layout_info)) = 0;
|
||
|
||
void
|
||
set_lang_adjust_rli (f)
|
||
void (*f) PARAMS ((record_layout_info));
|
||
{
|
||
lang_adjust_rli = f;
|
||
}
|
||
|
||
/* Begin laying out type T, which may be a RECORD_TYPE, UNION_TYPE, or
|
||
QUAL_UNION_TYPE. Return a pointer to a struct record_layout_info which
|
||
is to be passed to all other layout functions for this record. It is the
|
||
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));
|
||
|
||
rli->t = t;
|
||
|
||
/* 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->unpadded_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 (t))
|
||
rli->record_align = MAX (rli->record_align, STRUCTURE_SIZE_BOUNDARY);
|
||
#endif
|
||
|
||
rli->offset = size_zero_node;
|
||
rli->bitpos = bitsize_zero_node;
|
||
rli->prev_field = 0;
|
||
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)
|
||
{
|
||
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));
|
||
}
|
||
}
|
||
|
||
/* Print debugging information about the information in RLI. */
|
||
|
||
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, "\naligns: rec = %u, unpack = %u, unpad = %u, off = %u\n",
|
||
rli->record_align, rli->unpacked_align, rli->unpadded_align,
|
||
rli->offset_align);
|
||
if (rli->packed_maybe_necessary)
|
||
fprintf (stderr, "packed may be necessary\n");
|
||
|
||
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);
|
||
|
||
#ifdef 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);
|
||
#endif
|
||
|
||
TYPE_USER_ALIGN (rli->t) |= DECL_USER_ALIGN (field);
|
||
|
||
/* Union must be at least as aligned as any field requires. */
|
||
rli->record_align = MAX (rli->record_align, desired_align);
|
||
rli->unpadded_align = MAX (rli->unpadded_align, desired_align);
|
||
|
||
#ifdef PCC_BITFIELD_TYPE_MATTERS
|
||
/* On the m88000, a bit field of declare type `int' forces the
|
||
entire union to have `int' alignment. */
|
||
if (PCC_BITFIELD_TYPE_MATTERS && DECL_BIT_FIELD_TYPE (field))
|
||
{
|
||
rli->record_align = MAX (rli->record_align,
|
||
TYPE_ALIGN (TREE_TYPE (field)));
|
||
rli->unpadded_align = MAX (rli->unpadded_align,
|
||
TYPE_ALIGN (TREE_TYPE (field)));
|
||
}
|
||
#endif
|
||
|
||
/* We assume the union's size will be a multiple of a byte so we don't
|
||
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;
|
||
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;
|
||
}
|
||
|
||
/* 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);
|
||
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);
|
||
}
|
||
|
||
/* 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
|
||
|
||
#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. */
|
||
if ((* targetm.ms_bitfield_layout_p) (rli->t)
|
||
&& type != error_mark_node
|
||
&& DECL_BIT_FIELD_TYPE (field)
|
||
&& ! integer_zerop (TYPE_SIZE (type))
|
||
&& integer_zerop (DECL_SIZE (field)))
|
||
{
|
||
if (rli->prev_field
|
||
&& DECL_BIT_FIELD_TYPE (rli->prev_field)
|
||
&& ! integer_zerop (DECL_SIZE (rli->prev_field)))
|
||
{
|
||
rli->record_align = MAX (rli->record_align, desired_align);
|
||
rli->unpacked_align = MAX (rli->unpacked_align, TYPE_ALIGN (type));
|
||
}
|
||
else
|
||
desired_align = 1;
|
||
}
|
||
else
|
||
#ifdef PCC_BITFIELD_TYPE_MATTERS
|
||
if (PCC_BITFIELD_TYPE_MATTERS && type != error_mark_node
|
||
&& ! (* targetm.ms_bitfield_layout_p) (rli->t)
|
||
&& 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);
|
||
|
||
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->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));
|
||
}
|
||
}
|
||
else
|
||
#endif
|
||
{
|
||
rli->record_align = MAX (rli->record_align, desired_align);
|
||
rli->unpacked_align = MAX (rli->unpacked_align, TYPE_ALIGN (type));
|
||
rli->unpadded_align = MAX (rli->unpadded_align, DECL_ALIGN (field));
|
||
}
|
||
|
||
if (warn_packed && DECL_PACKED (field))
|
||
{
|
||
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 (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
|
||
{
|
||
/* 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);
|
||
}
|
||
|
||
if (! TREE_CONSTANT (rli->offset))
|
||
rli->offset_align = desired_align;
|
||
|
||
}
|
||
|
||
/* 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
|
||
&& ! (* targetm.ms_bitfield_layout_p) (rli->t)
|
||
&& 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
|
||
&& ! (* targetm.ms_bitfield_layout_p) (rli->t)
|
||
&& 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
|
||
|
||
/* See the docs for TARGET_MS_BITFIELD_LAYOUT_P for details. */
|
||
if ((* targetm.ms_bitfield_layout_p) (rli->t)
|
||
&& TREE_CODE (field) == FIELD_DECL
|
||
&& type != error_mark_node
|
||
&& ! DECL_PACKED (field)
|
||
&& rli->prev_field
|
||
&& DECL_SIZE (field)
|
||
&& host_integerp (DECL_SIZE (field), 1)
|
||
&& DECL_SIZE (rli->prev_field)
|
||
&& host_integerp (DECL_SIZE (rli->prev_field), 1)
|
||
&& host_integerp (rli->offset, 1)
|
||
&& host_integerp (TYPE_SIZE (type), 1)
|
||
&& host_integerp (TYPE_SIZE (TREE_TYPE (rli->prev_field)), 1)
|
||
&& ((DECL_BIT_FIELD_TYPE (rli->prev_field)
|
||
&& ! integer_zerop (DECL_SIZE (rli->prev_field)))
|
||
|| (DECL_BIT_FIELD_TYPE (field)
|
||
&& ! integer_zerop (DECL_SIZE (field))))
|
||
&& (! simple_cst_equal (TYPE_SIZE (type),
|
||
TYPE_SIZE (TREE_TYPE (rli->prev_field)))
|
||
/* If the previous field was a zero-sized bit-field, either
|
||
it was ignored, in which case we must ensure the proper
|
||
alignment of this field here, or it already forced the
|
||
alignment of this field, in which case forcing the
|
||
alignment again is harmless. So, do it in both cases. */
|
||
|| (DECL_BIT_FIELD_TYPE (rli->prev_field)
|
||
&& integer_zerop (DECL_SIZE (rli->prev_field)))))
|
||
{
|
||
unsigned int type_align = TYPE_ALIGN (type);
|
||
|
||
if (rli->prev_field
|
||
&& DECL_BIT_FIELD_TYPE (rli->prev_field)
|
||
/* If the previous bit-field is zero-sized, we've already
|
||
accounted for its alignment needs (or ignored it, if
|
||
appropriate) while placing it. */
|
||
&& ! integer_zerop (DECL_SIZE (rli->prev_field)))
|
||
type_align = MAX (type_align,
|
||
TYPE_ALIGN (TREE_TYPE (rli->prev_field)));
|
||
|
||
if (maximum_field_alignment != 0)
|
||
type_align = MIN (type_align, maximum_field_alignment);
|
||
|
||
rli->bitpos = round_up (rli->bitpos, type_align);
|
||
}
|
||
|
||
/* 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);
|
||
|
||
TYPE_USER_ALIGN (rli->t) |= user_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);
|
||
|
||
rli->prev_field = field;
|
||
|
||
/* 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)))
|
||
{
|
||
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 (rli->t) = ROUND_TYPE_ALIGN (rli->t, TYPE_ALIGN (rli->t),
|
||
rli->record_align);
|
||
#else
|
||
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 (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 (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
|
||
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 && 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;
|
||
|
||
#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 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 (simple_cst_equal (unpacked_size, TYPE_SIZE (rli->t)))
|
||
{
|
||
TYPE_PACKED (rli->t) = 0;
|
||
|
||
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)));
|
||
|
||
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");
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
/* Compute the TYPE_MODE for the TYPE (which is a RECORD_TYPE). */
|
||
|
||
void
|
||
compute_record_mode (type)
|
||
tree type;
|
||
{
|
||
tree field;
|
||
enum machine_mode mode = VOIDmode;
|
||
|
||
/* 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 (! 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 (TREE_TYPE (field)) == ERROR_MARK
|
||
|| (TYPE_MODE (TREE_TYPE (field)) == BLKmode
|
||
&& ! TYPE_NO_FORCE_BLK (TREE_TYPE (field)))
|
||
|| ! host_integerp (bit_position (field), 1)
|
||
|| DECL_SIZE (field) == 0
|
||
|| ! 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. */
|
||
|
||
/* On ia64-*-hpux we need to ensure that we don't change the
|
||
mode of a structure containing a single field or else we
|
||
will pass it incorrectly. Since a structure with a single
|
||
field causes mode to get set above we can't allow the
|
||
check for mode == VOIDmode in this case. Perhaps
|
||
MEMBER_TYPE_FORCES_BLK should be extended to include mode
|
||
as an argument and the check could be put in there for c4x. */
|
||
|
||
if ((mode == VOIDmode || FUNCTION_ARG_REG_LITTLE_ENDIAN)
|
||
&& MEMBER_TYPE_FORCES_BLK (field))
|
||
return;
|
||
#endif /* MEMBER_TYPE_FORCES_BLK */
|
||
}
|
||
|
||
/* 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_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;
|
||
}
|
||
}
|
||
|
||
/* 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 (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 (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
|
||
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);
|
||
}
|
||
|
||
/* Calculate the mode, size, and alignment for TYPE.
|
||
For an array type, calculate the element separation as well.
|
||
Record TYPE on the chain of permanent or temporary types
|
||
so that dbxout will find out about it.
|
||
|
||
TYPE_SIZE of a type is nonzero if the type has been laid out already.
|
||
layout_type does nothing on such a type.
|
||
|
||
If the type is incomplete, its TYPE_SIZE remains zero. */
|
||
|
||
void
|
||
layout_type (type)
|
||
tree type;
|
||
{
|
||
if (type == 0)
|
||
abort ();
|
||
|
||
/* Do nothing if type has been laid out before. */
|
||
if (TYPE_SIZE (type))
|
||
return;
|
||
|
||
switch (TREE_CODE (type))
|
||
{
|
||
case LANG_TYPE:
|
||
/* This kind of type is the responsibility
|
||
of the language-specific code. */
|
||
abort ();
|
||
|
||
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:
|
||
case ENUMERAL_TYPE:
|
||
case CHAR_TYPE:
|
||
if (TREE_CODE (TYPE_MIN_VALUE (type)) == INTEGER_CST
|
||
&& tree_int_cst_sgn (TYPE_MIN_VALUE (type)) >= 0)
|
||
TREE_UNSIGNED (type) = 1;
|
||
|
||
TYPE_MODE (type) = smallest_mode_for_size (TYPE_PRECISION (type),
|
||
MODE_INT);
|
||
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)));
|
||
TYPE_SIZE_UNIT (type) = size_int (GET_MODE_SIZE (TYPE_MODE (type)));
|
||
break;
|
||
|
||
case COMPLEX_TYPE:
|
||
TREE_UNSIGNED (type) = TREE_UNSIGNED (TREE_TYPE (type));
|
||
TYPE_MODE (type)
|
||
= mode_for_size (2 * TYPE_PRECISION (TREE_TYPE (type)),
|
||
(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)));
|
||
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:
|
||
/* 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);
|
||
TYPE_SIZE_UNIT (type) = size_int (POINTER_SIZE / BITS_PER_UNIT);
|
||
/* 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);
|
||
TYPE_SIZE_UNIT (type) = size_int ((2 * POINTER_SIZE) / BITS_PER_UNIT);
|
||
break;
|
||
|
||
case POINTER_TYPE:
|
||
case REFERENCE_TYPE:
|
||
{
|
||
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 index = TYPE_DOMAIN (type);
|
||
tree element = TREE_TYPE (type);
|
||
|
||
build_pointer_type (element);
|
||
|
||
/* We need to know both bounds in order to compute the size. */
|
||
if (index && TYPE_MAX_VALUE (index) && TYPE_MIN_VALUE (index)
|
||
&& TYPE_SIZE (element))
|
||
{
|
||
tree ub = TYPE_MAX_VALUE (index);
|
||
tree lb = TYPE_MIN_VALUE (index);
|
||
tree length;
|
||
tree element_size;
|
||
|
||
/* 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,
|
||
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)
|
||
&& (integer_zerop (TYPE_MAX_VALUE (element))
|
||
|| integer_onep (TYPE_MAX_VALUE (element)))
|
||
&& host_integerp (TYPE_MIN_VALUE (element), 1))
|
||
{
|
||
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,
|
||
convert (bitsizetype, length));
|
||
|
||
/* If we know the size of the element, calculate the total
|
||
size directly, rather than do some division thing below.
|
||
This optimization helps Fortran assumed-size arrays
|
||
(where the size of the array is determined at runtime)
|
||
substantially.
|
||
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 && ! integer_onep (element_size))
|
||
TYPE_SIZE_UNIT (type)
|
||
= size_binop (MULT_EXPR, TYPE_SIZE_UNIT (element), length);
|
||
}
|
||
|
||
/* Now round the alignment and size,
|
||
using machine-dependent criteria if any. */
|
||
|
||
#ifdef ROUND_TYPE_ALIGN
|
||
TYPE_ALIGN (type)
|
||
= ROUND_TYPE_ALIGN (type, TYPE_ALIGN (element), BITS_PER_UNIT);
|
||
#else
|
||
TYPE_ALIGN (type) = MAX (TYPE_ALIGN (element), BITS_PER_UNIT);
|
||
#endif
|
||
TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (element);
|
||
|
||
#ifdef ROUND_TYPE_SIZE
|
||
if (TYPE_SIZE (type) != 0)
|
||
{
|
||
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
|
||
#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 (TYPE_SIZE (type), MODE_INT, 1);
|
||
|
||
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;
|
||
TYPE_MODE (type) = BLKmode;
|
||
}
|
||
}
|
||
break;
|
||
}
|
||
|
||
case RECORD_TYPE:
|
||
case UNION_TYPE:
|
||
case QUAL_UNION_TYPE:
|
||
{
|
||
tree field;
|
||
record_layout_info rli;
|
||
|
||
/* Initialize the layout information. */
|
||
rli = start_record_layout (type);
|
||
|
||
/* 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));
|
||
|
||
/* 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));
|
||
|
||
if (lang_adjust_rli)
|
||
(*lang_adjust_rli) (rli);
|
||
|
||
/* Finish laying out the record. */
|
||
finish_record_layout (rli);
|
||
}
|
||
break;
|
||
|
||
case SET_TYPE: /* Used by Chill and Pascal. */
|
||
if (TREE_CODE (TYPE_MAX_VALUE (TYPE_DOMAIN (type))) != INTEGER_CST
|
||
|| TREE_CODE (TYPE_MIN_VALUE (TYPE_DOMAIN (type))) != INTEGER_CST)
|
||
abort ();
|
||
else
|
||
{
|
||
#ifndef SET_WORD_SIZE
|
||
#define SET_WORD_SIZE BITS_PER_WORD
|
||
#endif
|
||
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 > (int) alignment)
|
||
TYPE_MODE (type) = BLKmode;
|
||
else
|
||
TYPE_MODE (type) = mode_for_size (alignment, MODE_INT, 1);
|
||
|
||
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;
|
||
|
||
case FILE_TYPE:
|
||
/* 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 ();
|
||
}
|
||
|
||
/* 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;
|
||
}
|
||
|
||
/* Create and return a type for signed integers of PRECISION bits. */
|
||
|
||
tree
|
||
make_signed_type (precision)
|
||
int precision;
|
||
{
|
||
tree type = make_node (INTEGER_TYPE);
|
||
|
||
TYPE_PRECISION (type) = precision;
|
||
|
||
fixup_signed_type (type);
|
||
return type;
|
||
}
|
||
|
||
/* Create and return a type for unsigned integers of PRECISION bits. */
|
||
|
||
tree
|
||
make_unsigned_type (precision)
|
||
int precision;
|
||
{
|
||
tree type = make_node (INTEGER_TYPE);
|
||
|
||
TYPE_PRECISION (type) = precision;
|
||
|
||
fixup_unsigned_type (type);
|
||
return type;
|
||
}
|
||
|
||
/* 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. */
|
||
|
||
void
|
||
set_sizetype (type)
|
||
tree type;
|
||
{
|
||
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;
|
||
|
||
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);
|
||
else
|
||
fixup_signed_type (bitsizetype);
|
||
|
||
layout_type (bitsizetype);
|
||
|
||
if (TREE_UNSIGNED (type))
|
||
{
|
||
usizetype = sizetype;
|
||
ubitsizetype = bitsizetype;
|
||
ssizetype = copy_node (make_signed_type (oprecision));
|
||
sbitsizetype = copy_node (make_signed_type (precision));
|
||
}
|
||
else
|
||
{
|
||
ssizetype = sizetype;
|
||
sbitsizetype = bitsizetype;
|
||
usizetype = copy_node (make_unsigned_type (oprecision));
|
||
ubitsizetype = copy_node (make_unsigned_type (precision));
|
||
}
|
||
|
||
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, ARRAY_SIZE (sizetype_tab));
|
||
|
||
/* 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;
|
||
}
|
||
|
||
/* 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.
|
||
E.g. for Pascal, when the -fsigned-char option is given. */
|
||
|
||
void
|
||
fixup_signed_type (type)
|
||
tree type;
|
||
{
|
||
int precision = TYPE_PRECISION (type);
|
||
|
||
/* We can not represent properly constants greater then
|
||
2 * HOST_BITS_PER_WIDE_INT, still we need the types
|
||
as they are used by i386 vector extensions and friends. */
|
||
if (precision > HOST_BITS_PER_WIDE_INT * 2)
|
||
precision = HOST_BITS_PER_WIDE_INT * 2;
|
||
|
||
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));
|
||
|
||
TREE_TYPE (TYPE_MIN_VALUE (type)) = type;
|
||
TREE_TYPE (TYPE_MAX_VALUE (type)) = type;
|
||
|
||
/* Lay out the type: set its alignment, size, etc. */
|
||
layout_type (type);
|
||
}
|
||
|
||
/* Set the extreme values of TYPE based on its precision in bits,
|
||
then lay it out. This is used both in `make_unsigned_type'
|
||
and for enumeral types. */
|
||
|
||
void
|
||
fixup_unsigned_type (type)
|
||
tree type;
|
||
{
|
||
int precision = TYPE_PRECISION (type);
|
||
|
||
/* We can not represent properly constants greater then
|
||
2 * HOST_BITS_PER_WIDE_INT, still we need the types
|
||
as they are used by i386 vector extensions and friends. */
|
||
if (precision > HOST_BITS_PER_WIDE_INT * 2)
|
||
precision = HOST_BITS_PER_WIDE_INT * 2;
|
||
|
||
TYPE_MIN_VALUE (type) = build_int_2 (0, 0);
|
||
TYPE_MAX_VALUE (type)
|
||
= build_int_2 (precision - HOST_BITS_PER_WIDE_INT >= 0
|
||
? -1 : ((HOST_WIDE_INT) 1 << precision) - 1,
|
||
precision - HOST_BITS_PER_WIDE_INT > 0
|
||
? ((unsigned HOST_WIDE_INT) ~0
|
||
>> (HOST_BITS_PER_WIDE_INT
|
||
- (precision - HOST_BITS_PER_WIDE_INT)))
|
||
: 0);
|
||
TREE_TYPE (TYPE_MIN_VALUE (type)) = type;
|
||
TREE_TYPE (TYPE_MAX_VALUE (type)) = type;
|
||
|
||
/* Lay out the type: set its alignment, size, etc. */
|
||
layout_type (type);
|
||
}
|
||
|
||
/* Find the best machine mode to use when referencing a bit field of length
|
||
BITSIZE bits starting at BITPOS.
|
||
|
||
The underlying object is known to be aligned to a boundary of ALIGN bits.
|
||
If LARGEST_MODE is not VOIDmode, it means that we should not use a mode
|
||
larger than LARGEST_MODE (usually SImode).
|
||
|
||
If no mode meets all these conditions, we return VOIDmode. Otherwise, if
|
||
VOLATILEP is true or SLOW_BYTE_ACCESS is false, we return the smallest
|
||
mode meeting these conditions.
|
||
|
||
Otherwise (VOLATILEP is false and SLOW_BYTE_ACCESS is true), we return
|
||
the largest mode (but a mode no wider than UNITS_PER_WORD) that meets
|
||
all the conditions. */
|
||
|
||
enum machine_mode
|
||
get_best_mode (bitsize, bitpos, align, largest_mode, volatilep)
|
||
int bitsize, bitpos;
|
||
unsigned int align;
|
||
enum machine_mode largest_mode;
|
||
int volatilep;
|
||
{
|
||
enum machine_mode mode;
|
||
unsigned int unit = 0;
|
||
|
||
/* Find the narrowest integer mode that contains the bit field. */
|
||
for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT); mode != VOIDmode;
|
||
mode = GET_MODE_WIDER_MODE (mode))
|
||
{
|
||
unit = GET_MODE_BITSIZE (mode);
|
||
if ((bitpos % unit) + bitsize <= unit)
|
||
break;
|
||
}
|
||
|
||
if (mode == VOIDmode
|
||
/* It is tempting to omit the following line
|
||
if STRICT_ALIGNMENT is true.
|
||
But that is incorrect, since if the bitfield uses part of 3 bytes
|
||
and we use a 4-byte mode, we could get a spurious segv
|
||
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) > align
|
||
|| (largest_mode != VOIDmode && unit > GET_MODE_BITSIZE (largest_mode)))
|
||
return VOIDmode;
|
||
|
||
if (SLOW_BYTE_ACCESS && ! volatilep)
|
||
{
|
||
enum machine_mode wide_mode = VOIDmode, tmode;
|
||
|
||
for (tmode = GET_CLASS_NARROWEST_MODE (MODE_INT); tmode != VOIDmode;
|
||
tmode = GET_MODE_WIDER_MODE (tmode))
|
||
{
|
||
unit = GET_MODE_BITSIZE (tmode);
|
||
if (bitpos / unit == (bitpos + bitsize - 1) / unit
|
||
&& unit <= BITS_PER_WORD
|
||
&& unit <= MIN (align, BIGGEST_ALIGNMENT)
|
||
&& (largest_mode == VOIDmode
|
||
|| unit <= GET_MODE_BITSIZE (largest_mode)))
|
||
wide_mode = tmode;
|
||
}
|
||
|
||
if (wide_mode != VOIDmode)
|
||
return wide_mode;
|
||
}
|
||
|
||
return mode;
|
||
}
|
||
|
||
/* This function is run once to initialize stor-layout.c. */
|
||
|
||
void
|
||
init_stor_layout_once ()
|
||
{
|
||
ggc_add_tree_root (&pending_sizes, 1);
|
||
}
|