/* C-compiler utilities for types and variables storage layout
Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1996, 1998,
- 1999, 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
+ 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
+ Free Software Foundation, Inc.
This file is part of GCC.
#include "flags.h"
#include "function.h"
#include "expr.h"
+#include "output.h"
#include "toplev.h"
#include "ggc.h"
#include "target.h"
case MODE_COMPLEX_INT:
case MODE_COMPLEX_FLOAT:
case MODE_FLOAT:
+ case MODE_DECIMAL_FLOAT:
case MODE_VECTOR_INT:
case MODE_VECTOR_FLOAT:
mode = mode_for_size (GET_MODE_BITSIZE (mode), MODE_INT, 0);
/* For fields, it's a bit more complicated... */
{
bool old_user_align = DECL_USER_ALIGN (decl);
+ bool zero_bitfield = false;
+ bool packed_p = DECL_PACKED (decl);
+ unsigned int mfa;
if (DECL_BIT_FIELD (decl))
{
DECL_BIT_FIELD_TYPE (decl) = type;
/* A zero-length bit-field affects the alignment of the next
- field. */
+ field. In essence such bit-fields are not influenced by
+ any packing due to #pragma pack or attribute packed. */
if (integer_zerop (DECL_SIZE (decl))
- && ! DECL_PACKED (decl)
&& ! targetm.ms_bitfield_layout_p (DECL_FIELD_CONTEXT (decl)))
{
+ zero_bitfield = true;
+ packed_p = false;
#ifdef PCC_BITFIELD_TYPE_MATTERS
if (PCC_BITFIELD_TYPE_MATTERS)
do_type_align (type, decl);
&& DECL_ALIGN (decl) >= TYPE_ALIGN (type))
DECL_BIT_FIELD (decl) = 0;
}
- else if (DECL_PACKED (decl) && DECL_USER_ALIGN (decl))
+ else if (packed_p && DECL_USER_ALIGN (decl))
/* Don't touch DECL_ALIGN. For other packed fields, go ahead and
round up; we'll reduce it again below. We want packing to
supersede USER_ALIGN inherited from the type, but defer to
Note that do_type_align may set DECL_USER_ALIGN, so we need to
check old_user_align instead. */
- if (DECL_PACKED (decl)
+ if (packed_p
&& !old_user_align
&& (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);
- if (! DECL_USER_ALIGN (decl) && ! DECL_PACKED (decl))
+ if (! packed_p && ! DECL_USER_ALIGN (decl))
{
/* Some targets (i.e. i386, VMS) limit struct field alignment
to a lower boundary than alignment of variables unless
#endif
}
+ if (zero_bitfield)
+ mfa = initial_max_fld_align * BITS_PER_UNIT;
+ else
+ mfa = maximum_field_alignment;
/* Should this be controlled by DECL_USER_ALIGN, too? */
- if (maximum_field_alignment != 0)
- DECL_ALIGN (decl) = MIN (DECL_ALIGN (decl), maximum_field_alignment);
+ if (mfa != 0)
+ DECL_ALIGN (decl) = MIN (DECL_ALIGN (decl), mfa);
}
/* Evaluate nonconstant size only once, either now or as soon as safe. */
int size_as_int = TREE_INT_CST_LOW (size);
if (compare_tree_int (size, size_as_int) == 0)
- warning (0, "%Jsize of %qD is %d bytes", decl, decl, size_as_int);
+ warning (0, "size of %q+D is %d bytes", decl, size_as_int);
else
- warning (0, "%Jsize of %qD is larger than %d bytes",
- decl, decl, larger_than_size);
+ warning (0, "size of %q+D is larger than %wd bytes",
+ decl, larger_than_size);
}
}
type_align = ADJUST_FIELD_ALIGN (field, type_align);
#endif
- if (maximum_field_alignment != 0)
+ /* Targets might chose to handle unnamed and hence possibly
+ zero-width bitfield. Those are not influenced by #pragmas
+ or packed attributes. */
+ if (integer_zerop (DECL_SIZE (field)))
+ {
+ if (initial_max_fld_align)
+ type_align = MIN (type_align,
+ initial_max_fld_align * BITS_PER_UNIT);
+ }
+ else 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);
/* The type of this field. */
tree type = TREE_TYPE (field);
- if (TREE_CODE (field) == ERROR_MARK || TREE_CODE (type) == ERROR_MARK)
- return;
+ gcc_assert (TREE_CODE (field) != ERROR_MARK);
+ if (TREE_CODE (type) == ERROR_MARK)
+ {
+ if (TREE_CODE (field) == FIELD_DECL)
+ {
+ DECL_FIELD_OFFSET (field) = size_int (0);
+ DECL_FIELD_BIT_OFFSET (field) = bitsize_int (0);
+ }
+
+ 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
if (TYPE_ALIGN (type) > desired_align)
{
if (STRICT_ALIGNMENT)
- warning (OPT_Wattributes, "%Jpacked attribute causes "
- "inefficient alignment for %qD", field, field);
+ warning (OPT_Wattributes, "packed attribute causes "
+ "inefficient alignment for %q+D", field);
else
- warning (OPT_Wattributes, "%Jpacked attribute is "
- "unnecessary for %qD", field, field);
+ warning (OPT_Wattributes, "packed attribute is "
+ "unnecessary for %q+D", field);
}
}
else
/* No, we need to skip space before this field.
Bump the cumulative size to multiple of field alignment. */
- warning (OPT_Wpadded, "%Jpadding struct to align %qD", field, field);
+ warning (OPT_Wpadded, "padding struct to align %q+D", field);
/* If the alignment is still within offset_align, just align
the bit position. */
if (DECL_BIT_FIELD_TYPE (field))
{
unsigned int type_align = TYPE_ALIGN (type);
+ unsigned int mfa = maximum_field_alignment;
+
+ if (integer_zerop (DECL_SIZE (field)))
+ mfa = initial_max_fld_align * BITS_PER_UNIT;
/* Only the MS bitfields use this. We used to also put any kind of
packed bit fields into prev_field, but that makes no sense, because
are also not fulfilled.
There is no sane value to set rli->remaining_in_alignment to when
a packed bitfield in prev_field is unaligned. */
- if (maximum_field_alignment != 0)
- type_align = MIN (type_align, maximum_field_alignment);
+ if (mfa != 0)
+ type_align = MIN (type_align, mfa);
gcc_assert (rli->prev_field
|| actual_align >= type_align || DECL_PACKED (field)
|| integer_zerop (DECL_SIZE (field))
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)))
+ else if (TREE_CODE (DECL_SIZE (field)) != INTEGER_CST
+ || TREE_CONSTANT_OVERFLOW (DECL_SIZE (field)))
{
rli->offset
= size_binop (PLUS_EXPR, rli->offset,
#endif /* MEMBER_TYPE_FORCES_BLK */
}
- TYPE_MODE (type) = mode_for_size_tree (TYPE_SIZE (type), MODE_INT, 1);
-
/* If we only have one real field; use its mode if that mode's size
matches the type's size. This only applies to RECORD_TYPE. This
does not apply to unions. */
if (TREE_CODE (type) == RECORD_TYPE && mode != VOIDmode
- && GET_MODE_SIZE (mode) == GET_MODE_SIZE (TYPE_MODE (type)))
+ && host_integerp (TYPE_SIZE (type), 1)
+ && GET_MODE_BITSIZE (mode) == TREE_INT_CST_LOW (TYPE_SIZE (type)))
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. */
&& 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;
+ unsigned mode_align = GET_MODE_ALIGNMENT (TYPE_MODE (type));
+
+ /* Don't override a larger alignment requirement coming from a user
+ alignment of one of the fields. */
+ if (mode_align >= TYPE_ALIGN (type))
+ {
+ TYPE_ALIGN (type) = mode_align;
+ TYPE_USER_ALIGN (type) = 0;
+ }
}
/* Do machine-dependent extra alignment. */
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)
TYPE_UNSIGNED (type) = 1;
enum machine_mode mode;
/* First, look for a supported vector type. */
- if (GET_MODE_CLASS (innermode) == MODE_FLOAT)
+ if (SCALAR_FLOAT_MODE_P (innermode))
mode = MIN_MODE_VECTOR_FLOAT;
else
mode = MIN_MODE_VECTOR_INT;
TYPE_MODE (type) = BLKmode;
}
}
+ /* When the element size is constant, check that it is at least as
+ large as the element alignment. */
+ if (TYPE_SIZE_UNIT (element)
+ && TREE_CODE (TYPE_SIZE_UNIT (element)) == INTEGER_CST
+ /* If TYPE_SIZE_UNIT overflowed, then it is certainly larger than
+ TYPE_ALIGN_UNIT. */
+ && !TREE_CONSTANT_OVERFLOW (TYPE_SIZE_UNIT (element))
+ && !integer_zerop (TYPE_SIZE_UNIT (element))
+ && compare_tree_int (TYPE_SIZE_UNIT (element),
+ TYPE_ALIGN_UNIT (element)) < 0)
+ error ("alignment of array elements is greater than element size");
break;
}
TYPE_PRECISION (t) = precision;
TYPE_UID (t) = TYPE_UID (bitsizetype);
TYPE_IS_SIZETYPE (t) = 1;
+
/* Replace our original stub bitsizetype. */
memcpy (bitsizetype, t, tree_size (bitsizetype));
+ TYPE_MAIN_VARIANT (bitsizetype) = bitsizetype;
if (TYPE_UNSIGNED (type))
{
ssizetype = sizetype;
sbitsizetype = bitsizetype;
}
+
+ /* If SIZETYPE is unsigned, we need to fix TYPE_MAX_VALUE so that
+ it is sign extended in a way consistent with force_fit_type. */
+ if (TYPE_UNSIGNED (type))
+ {
+ tree orig_max, new_max;
+
+ orig_max = TYPE_MAX_VALUE (sizetype);
+
+ /* Build a new node with the same values, but a different type. */
+ new_max = build_int_cst_wide (sizetype,
+ TREE_INT_CST_LOW (orig_max),
+ TREE_INT_CST_HIGH (orig_max));
+
+ /* Now sign extend it using force_fit_type to ensure
+ consistency. */
+ new_max = force_fit_type (new_max, 0, 0, 0);
+ TYPE_MAX_VALUE (sizetype) = new_max;
+ }
}
\f
-/* TYPE is an integral type, i.e., an INTEGRAL_TYPE, ENUMERAL_TYPE,
- BOOLEAN_TYPE, or CHAR_TYPE. Set TYPE_MIN_VALUE and TYPE_MAX_VALUE
+/* TYPE is an integral type, i.e., an INTEGRAL_TYPE, ENUMERAL_TYPE
+ or BOOLEAN_TYPE. Set TYPE_MIN_VALUE and TYPE_MAX_VALUE
for TYPE, based on the PRECISION and whether or not the TYPE
IS_UNSIGNED. PRECISION need not correspond to a width supported
natively by the hardware; for example, on a machine with 8-bit,
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