#include "dwarf2/loc.h"
#include "gdbcore.h"
#include "floatformat.h"
+#include <algorithm>
/* Initialize BADNESS constants. */
case PROP_LOCEXPR:
case PROP_LOCLIST:
return l.data.baton == r.data.baton;
+ case PROP_VARIANT_PARTS:
+ return l.data.variant_parts == r.data.variant_parts;
+ case PROP_TYPE:
+ return l.data.original_type == r.data.original_type;
}
gdb_assert_not_reached ("unhandled dynamic_prop kind");
if (TYPE_ALLOCATED_PROP (type))
return 1;
+ struct dynamic_prop *prop = get_dyn_prop (DYN_PROP_VARIANT_PARTS, type);
+ if (prop != nullptr && prop->kind != PROP_TYPE)
+ return 1;
+
switch (TYPE_CODE (type))
{
case TYPE_CODE_RANGE:
return resolved_type;
}
+/* See gdbtypes.h. */
+
+bool
+variant::matches (ULONGEST value, bool is_unsigned) const
+{
+ for (const discriminant_range &range : discriminants)
+ if (range.contains (value, is_unsigned))
+ return true;
+ return false;
+}
+
+static void
+compute_variant_fields_inner (struct type *type,
+ struct property_addr_info *addr_stack,
+ const variant_part &part,
+ std::vector<bool> &flags);
+
+/* A helper function to determine which variant fields will be active.
+ This handles both the variant's direct fields, and any variant
+ parts embedded in this variant. TYPE is the type we're examining.
+ ADDR_STACK holds information about the concrete object. VARIANT is
+ the current variant to be handled. FLAGS is where the results are
+ stored -- this function sets the Nth element in FLAGS if the
+ corresponding field is enabled. ENABLED is whether this variant is
+ enabled or not. */
+
+static void
+compute_variant_fields_recurse (struct type *type,
+ struct property_addr_info *addr_stack,
+ const variant &variant,
+ std::vector<bool> &flags,
+ bool enabled)
+{
+ for (int field = variant.first_field; field < variant.last_field; ++field)
+ flags[field] = enabled;
+
+ for (const variant_part &new_part : variant.parts)
+ {
+ if (enabled)
+ compute_variant_fields_inner (type, addr_stack, new_part, flags);
+ else
+ {
+ for (const auto &sub_variant : new_part.variants)
+ compute_variant_fields_recurse (type, addr_stack, sub_variant,
+ flags, enabled);
+ }
+ }
+}
+
+/* A helper function to determine which variant fields will be active.
+ This evaluates the discriminant, decides which variant (if any) is
+ active, and then updates FLAGS to reflect which fields should be
+ available. TYPE is the type we're examining. ADDR_STACK holds
+ information about the concrete object. VARIANT is the current
+ variant to be handled. FLAGS is where the results are stored --
+ this function sets the Nth element in FLAGS if the corresponding
+ field is enabled. */
+
+static void
+compute_variant_fields_inner (struct type *type,
+ struct property_addr_info *addr_stack,
+ const variant_part &part,
+ std::vector<bool> &flags)
+{
+ /* Evaluate the discriminant. */
+ gdb::optional<ULONGEST> discr_value;
+ if (part.discriminant_index != -1)
+ {
+ int idx = part.discriminant_index;
+
+ if (TYPE_FIELD_LOC_KIND (type, idx) != FIELD_LOC_KIND_BITPOS)
+ error (_("Cannot determine struct field location"
+ " (invalid location kind)"));
+
+ if (addr_stack->valaddr != NULL)
+ discr_value = unpack_field_as_long (type, addr_stack->valaddr, idx);
+ else
+ {
+ CORE_ADDR addr = (addr_stack->addr
+ + (TYPE_FIELD_BITPOS (type, idx)
+ / TARGET_CHAR_BIT));
+
+ LONGEST bitsize = TYPE_FIELD_BITSIZE (type, idx);
+ LONGEST size = bitsize / 8;
+ if (size == 0)
+ size = TYPE_LENGTH (TYPE_FIELD_TYPE (type, idx));
+
+ gdb_byte bits[sizeof (ULONGEST)];
+ read_memory (addr, bits, size);
+
+ LONGEST bitpos = (TYPE_FIELD_BITPOS (type, idx)
+ % TARGET_CHAR_BIT);
+
+ discr_value = unpack_bits_as_long (TYPE_FIELD_TYPE (type, idx),
+ bits, bitpos, bitsize);
+ }
+ }
+
+ /* Go through each variant and see which applies. */
+ const variant *default_variant = nullptr;
+ const variant *applied_variant = nullptr;
+ for (const auto &variant : part.variants)
+ {
+ if (variant.is_default ())
+ default_variant = &variant;
+ else if (discr_value.has_value ()
+ && variant.matches (*discr_value, part.is_unsigned))
+ {
+ applied_variant = &variant;
+ break;
+ }
+ }
+ if (applied_variant == nullptr)
+ applied_variant = default_variant;
+
+ for (const auto &variant : part.variants)
+ compute_variant_fields_recurse (type, addr_stack, variant,
+ flags, applied_variant == &variant);
+}
+
+/* Determine which variant fields are available in TYPE. The enabled
+ fields are stored in RESOLVED_TYPE. ADDR_STACK holds information
+ about the concrete object. PARTS describes the top-level variant
+ parts for this type. */
+
+static void
+compute_variant_fields (struct type *type,
+ struct type *resolved_type,
+ struct property_addr_info *addr_stack,
+ const gdb::array_view<variant_part> &parts)
+{
+ /* Assume all fields are included by default. */
+ std::vector<bool> flags (TYPE_NFIELDS (resolved_type), true);
+
+ /* Now disable fields based on the variants that control them. */
+ for (const auto &part : parts)
+ compute_variant_fields_inner (type, addr_stack, part, flags);
+
+ TYPE_NFIELDS (resolved_type) = std::count (flags.begin (), flags.end (),
+ true);
+ TYPE_FIELDS (resolved_type)
+ = (struct field *) TYPE_ALLOC (resolved_type,
+ TYPE_NFIELDS (resolved_type)
+ * sizeof (struct field));
+ int out = 0;
+ for (int i = 0; i < TYPE_NFIELDS (type); ++i)
+ {
+ if (!flags[i])
+ continue;
+
+ TYPE_FIELD (resolved_type, out) = TYPE_FIELD (type, i);
+ ++out;
+ }
+}
+
/* Resolve dynamic bounds of members of the struct TYPE to static
bounds. ADDR_STACK is a stack of struct property_addr_info to
be used if needed during the dynamic resolution. */
gdb_assert (TYPE_NFIELDS (type) > 0);
resolved_type = copy_type (type);
- TYPE_FIELDS (resolved_type)
- = (struct field *) TYPE_ALLOC (resolved_type,
- TYPE_NFIELDS (resolved_type)
- * sizeof (struct field));
- memcpy (TYPE_FIELDS (resolved_type),
- TYPE_FIELDS (type),
- TYPE_NFIELDS (resolved_type) * sizeof (struct field));
+
+ struct dynamic_prop *variant_prop = get_dyn_prop (DYN_PROP_VARIANT_PARTS,
+ resolved_type);
+ if (variant_prop != nullptr && variant_prop->kind == PROP_VARIANT_PARTS)
+ {
+ compute_variant_fields (type, resolved_type, addr_stack,
+ *variant_prop->data.variant_parts);
+ /* We want to leave the property attached, so that the Rust code
+ can tell whether the type was originally an enum. */
+ variant_prop->kind = PROP_TYPE;
+ variant_prop->data.original_type = type;
+ }
+ else
+ {
+ TYPE_FIELDS (resolved_type)
+ = (struct field *) TYPE_ALLOC (resolved_type,
+ TYPE_NFIELDS (resolved_type)
+ * sizeof (struct field));
+ memcpy (TYPE_FIELDS (resolved_type),
+ TYPE_FIELDS (type),
+ TYPE_NFIELDS (resolved_type) * sizeof (struct field));
+ }
+
for (i = 0; i < TYPE_NFIELDS (resolved_type); ++i)
{
unsigned new_bit_length;
struct property_addr_info pinfo;
- if (field_is_static (&TYPE_FIELD (type, i)))
+ if (field_is_static (&TYPE_FIELD (resolved_type, i)))
continue;
/* As we know this field is not a static field, the field's
that verification indicates a bug in our code, the error
is not severe enough to suggest to the user he stops
his debugging session because of it. */
- if (TYPE_FIELD_LOC_KIND (type, i) != FIELD_LOC_KIND_BITPOS)
+ if (TYPE_FIELD_LOC_KIND (resolved_type, i) != FIELD_LOC_KIND_BITPOS)
error (_("Cannot determine struct field location"
" (invalid location kind)"));
- pinfo.type = check_typedef (TYPE_FIELD_TYPE (type, i));
+ pinfo.type = check_typedef (TYPE_FIELD_TYPE (resolved_type, i));
pinfo.valaddr = addr_stack->valaddr;
pinfo.addr
= (addr_stack->addr
#include "gdbsupport/underlying.h"
#include "gdbsupport/print-utils.h"
#include "dwarf2.h"
+#include "gdb_obstack.h"
/* Forward declarations for prototypes. */
struct field;
#define TYPE_IS_ALLOCATABLE(t) \
(get_dyn_prop (DYN_PROP_ALLOCATED, t) != NULL)
+/* * True if this type has variant parts. */
+#define TYPE_HAS_VARIANT_PARTS(t) \
+ (get_dyn_prop (DYN_PROP_VARIANT_PARTS, t) != nullptr)
+
/* * Instruction-space delimited type. This is for Harvard architectures
which have separate instruction and data address spaces (and perhaps
others).
#define TYPE_ADDRESS_CLASS_ALL(t) (TYPE_INSTANCE_FLAGS(t) \
& TYPE_INSTANCE_FLAG_ADDRESS_CLASS_ALL)
+/* * Information about a single discriminant. */
+
+struct discriminant_range
+{
+ /* * The range of values for the variant. This is an inclusive
+ range. */
+ ULONGEST low, high;
+
+ /* * Return true if VALUE is contained in this range. IS_UNSIGNED
+ is true if this should be an unsigned comparison; false for
+ signed. */
+ bool contains (ULONGEST value, bool is_unsigned) const
+ {
+ if (is_unsigned)
+ return value >= low && value <= high;
+ LONGEST valuel = (LONGEST) value;
+ return valuel >= (LONGEST) low && valuel <= (LONGEST) high;
+ }
+};
+
+struct variant_part;
+
+/* * A single variant. A variant has a list of discriminant values.
+ When the discriminator matches one of these, the variant is
+ enabled. Each variant controls zero or more fields; and may also
+ control other variant parts as well. This struct corresponds to
+ DW_TAG_variant in DWARF. */
+
+struct variant : allocate_on_obstack
+{
+ /* * The discriminant ranges for this variant. */
+ gdb::array_view<discriminant_range> discriminants;
+
+ /* * The fields controlled by this variant. This is inclusive on
+ the low end and exclusive on the high end. A variant may not
+ control any fields, in which case the two values will be equal.
+ These are indexes into the type's array of fields. */
+ int first_field;
+ int last_field;
+
+ /* * Variant parts controlled by this variant. */
+ gdb::array_view<variant_part> parts;
+
+ /* * Return true if this is the default variant. The default
+ variant can be recognized because it has no associated
+ discriminants. */
+ bool is_default () const
+ {
+ return discriminants.empty ();
+ }
+
+ /* * Return true if this variant matches VALUE. IS_UNSIGNED is true
+ if this should be an unsigned comparison; false for signed. */
+ bool matches (ULONGEST value, bool is_unsigned) const;
+};
+
+/* * A variant part. Each variant part has an optional discriminant
+ and holds an array of variants. This struct corresponds to
+ DW_TAG_variant_part in DWARF. */
+
+struct variant_part : allocate_on_obstack
+{
+ /* * The index of the discriminant field in the outer type. This is
+ an index into the type's array of fields. If this is -1, there
+ is no discriminant, and only the default variant can be
+ considered to be selected. */
+ int discriminant_index;
+
+ /* * True if this discriminant is unsigned; false if signed. This
+ comes from the type of the discriminant. */
+ bool is_unsigned;
+
+ /* * The variants that are controlled by this variant part. Note
+ that these will always be sorted by field number. */
+ gdb::array_view<variant> variants;
+};
+
+
/* * Information needed for a discriminated union. A discriminated
union is handled somewhat differently from an ordinary union.
PROP_CONST, /* Constant. */
PROP_ADDR_OFFSET, /* Address offset. */
PROP_LOCEXPR, /* Location expression. */
- PROP_LOCLIST /* Location list. */
+ PROP_LOCLIST, /* Location list. */
+ PROP_VARIANT_PARTS, /* Variant parts. */
+ PROP_TYPE, /* Type. */
};
union dynamic_prop_data
/* Storage for dynamic property. */
void *baton;
+
+ /* Storage of variant parts for a type. A type with variant parts
+ has all its fields "linearized" -- stored in a single field
+ array, just as if they had all been declared that way. The
+ variant parts are attached via a dynamic property, and then are
+ used to control which fields end up in the final type during
+ dynamic type resolution. */
+
+ const gdb::array_view<variant_part> *variant_parts;
+
+ /* Once a variant type is resolved, we may want to be able to go
+ from the resolved type to the original type. In this case we
+ rewrite the property's kind and set this field. */
+
+ struct type *original_type;
};
/* * Used to store a dynamic property. */
/* A property holding information about a discriminated union. */
DYN_PROP_DISCRIMINATED,
+
+ /* A property holding variant parts. */
+ DYN_PROP_VARIANT_PARTS,
};
/* * List for dynamic type attributes. */
projects / binutils-gdb.git / commitdiff