Add support for untagged unions in Rust
2016-10-28 Manish Goregaokar <manish@mozilla.com>
gdb/ChangeLog:
* rust-lang.c (rust_union_is_untagged): Add function to
check if a union is an untagged unioni
(rust_val_print): Handle printing of untagged union values
(rust_print_type): Handle printing of untagged union types
(rust_evaluate_subexp): Handle evaluating field
access on untagged unions
This commit is contained in:
Manish Goregaokar
parent
51a789c3bf
commit
b96645f1a1
|
|
@ -1,3 +1,11 @@
|
|||
2016-10-28 Manish Goregaokar <manish@mozilla.com>
|
||||
|
||||
* rust-lang.c (rust_union_is_untagged): Add function to
|
||||
check if a union is an untagged unioni
|
||||
(rust_val_print): Handle printing of untagged union values
|
||||
(rust_print_type): Handle printing of untagged union types
|
||||
(rust_evaluate_subexp): Handle evaluating field
|
||||
access on untagged unions
|
||||
|
||||
2016-10-27 Manish Goregaokar <manish@mozilla.com>
|
||||
|
||||
|
|
|
|||
323
gdb/rust-lang.c
323
gdb/rust-lang.c
|
|
@ -93,6 +93,28 @@ struct disr_info
|
|||
|
||||
#define RUST_ENCODED_ENUM_HIDDEN 1
|
||||
|
||||
/* Whether or not a TYPE_CODE_UNION value is an untagged union
|
||||
as opposed to being a regular Rust enum. */
|
||||
static bool
|
||||
rust_union_is_untagged (struct type *type)
|
||||
{
|
||||
/* Unions must have at least one field. */
|
||||
if (TYPE_NFIELDS (type) == 0)
|
||||
return false;
|
||||
/* If the first field is named, but the name has the rust enum prefix,
|
||||
it is an enum. */
|
||||
if (strncmp (TYPE_FIELD_NAME (type, 0), RUST_ENUM_PREFIX,
|
||||
strlen (RUST_ENUM_PREFIX)) == 0)
|
||||
return false;
|
||||
/* Unions only have named fields. */
|
||||
for (int i = 0; i < TYPE_NFIELDS (type); ++i)
|
||||
{
|
||||
if (strlen (TYPE_FIELD_NAME (type, i)) == 0)
|
||||
return false;
|
||||
}
|
||||
return true;
|
||||
}
|
||||
|
||||
/* Utility function to get discriminant info for a given value. */
|
||||
|
||||
static struct disr_info
|
||||
|
|
@ -456,6 +478,85 @@ rust_printstr (struct ui_file *stream, struct type *type,
|
|||
|
||||
|
||||
|
||||
/* rust_print_type branch for structs and untagged unions. */
|
||||
|
||||
static void
|
||||
val_print_struct (struct type *type, const gdb_byte *valaddr,
|
||||
int embedded_offset, CORE_ADDR address, struct ui_file *stream,
|
||||
int recurse, const struct value *val,
|
||||
const struct value_print_options *options)
|
||||
{
|
||||
int i;
|
||||
int first_field;
|
||||
int is_tuple = rust_tuple_type_p (type);
|
||||
int is_tuple_struct = !is_tuple && rust_tuple_struct_type_p (type);
|
||||
struct value_print_options opts;
|
||||
|
||||
if (!is_tuple)
|
||||
{
|
||||
if (TYPE_TAG_NAME (type) != NULL)
|
||||
fprintf_filtered (stream, "%s", TYPE_TAG_NAME (type));
|
||||
|
||||
if (TYPE_NFIELDS (type) == 0)
|
||||
return;
|
||||
|
||||
if (TYPE_TAG_NAME (type) != NULL)
|
||||
fputs_filtered (" ", stream);
|
||||
}
|
||||
|
||||
if (is_tuple || is_tuple_struct)
|
||||
fputs_filtered ("(", stream);
|
||||
else
|
||||
fputs_filtered ("{", stream);
|
||||
|
||||
opts = *options;
|
||||
opts.deref_ref = 0;
|
||||
|
||||
first_field = 1;
|
||||
for (i = 0; i < TYPE_NFIELDS (type); ++i)
|
||||
{
|
||||
if (field_is_static (&TYPE_FIELD (type, i)))
|
||||
continue;
|
||||
|
||||
if (!first_field)
|
||||
fputs_filtered (",", stream);
|
||||
|
||||
if (options->prettyformat)
|
||||
{
|
||||
fputs_filtered ("\n", stream);
|
||||
print_spaces_filtered (2 + 2 * recurse, stream);
|
||||
}
|
||||
else if (!first_field)
|
||||
fputs_filtered (" ", stream);
|
||||
|
||||
first_field = 0;
|
||||
|
||||
if (!is_tuple && !is_tuple_struct)
|
||||
{
|
||||
fputs_filtered (TYPE_FIELD_NAME (type, i), stream);
|
||||
fputs_filtered (": ", stream);
|
||||
}
|
||||
|
||||
val_print (TYPE_FIELD_TYPE (type, i),
|
||||
valaddr,
|
||||
embedded_offset + TYPE_FIELD_BITPOS (type, i) / 8,
|
||||
address,
|
||||
stream, recurse + 1, val, &opts,
|
||||
current_language);
|
||||
}
|
||||
|
||||
if (options->prettyformat)
|
||||
{
|
||||
fputs_filtered ("\n", stream);
|
||||
print_spaces_filtered (2 * recurse, stream);
|
||||
}
|
||||
|
||||
if (is_tuple || is_tuple_struct)
|
||||
fputs_filtered (")", stream);
|
||||
else
|
||||
fputs_filtered ("}", stream);
|
||||
}
|
||||
|
||||
static const struct generic_val_print_decorations rust_decorations =
|
||||
{
|
||||
/* Complex isn't used in Rust, but we provide C-ish values just in
|
||||
|
|
@ -567,6 +668,18 @@ rust_val_print (struct type *type, const gdb_byte *valaddr, int embedded_offset,
|
|||
struct value_print_options opts;
|
||||
struct cleanup *cleanup;
|
||||
|
||||
/* Untagged unions are printed as if they are structs.
|
||||
Since the field bit positions overlap in the debuginfo,
|
||||
the code for printing a union is same as that for a struct,
|
||||
the only difference is that the input type will have overlapping
|
||||
fields. */
|
||||
if (rust_union_is_untagged (type))
|
||||
{
|
||||
val_print_struct (type, valaddr, embedded_offset, address, stream,
|
||||
recurse, val, options);
|
||||
break;
|
||||
}
|
||||
|
||||
opts = *options;
|
||||
opts.deref_ref = 0;
|
||||
|
||||
|
|
@ -639,77 +752,8 @@ rust_val_print (struct type *type, const gdb_byte *valaddr, int embedded_offset,
|
|||
break;
|
||||
|
||||
case TYPE_CODE_STRUCT:
|
||||
{
|
||||
int i;
|
||||
int first_field;
|
||||
int is_tuple = rust_tuple_type_p (type);
|
||||
int is_tuple_struct = !is_tuple && rust_tuple_struct_type_p (type);
|
||||
struct value_print_options opts;
|
||||
|
||||
if (!is_tuple)
|
||||
{
|
||||
if (TYPE_TAG_NAME (type) != NULL)
|
||||
fprintf_filtered (stream, "%s", TYPE_TAG_NAME (type));
|
||||
|
||||
if (TYPE_NFIELDS (type) == 0)
|
||||
break;
|
||||
|
||||
if (TYPE_TAG_NAME (type) != NULL)
|
||||
fputs_filtered (" ", stream);
|
||||
}
|
||||
|
||||
if (is_tuple || is_tuple_struct)
|
||||
fputs_filtered ("(", stream);
|
||||
else
|
||||
fputs_filtered ("{", stream);
|
||||
|
||||
opts = *options;
|
||||
opts.deref_ref = 0;
|
||||
|
||||
first_field = 1;
|
||||
for (i = 0; i < TYPE_NFIELDS (type); ++i)
|
||||
{
|
||||
if (field_is_static (&TYPE_FIELD (type, i)))
|
||||
continue;
|
||||
|
||||
if (!first_field)
|
||||
fputs_filtered (",", stream);
|
||||
|
||||
if (options->prettyformat)
|
||||
{
|
||||
fputs_filtered ("\n", stream);
|
||||
print_spaces_filtered (2 + 2 * recurse, stream);
|
||||
}
|
||||
else if (!first_field)
|
||||
fputs_filtered (" ", stream);
|
||||
|
||||
first_field = 0;
|
||||
|
||||
if (!is_tuple && !is_tuple_struct)
|
||||
{
|
||||
fputs_filtered (TYPE_FIELD_NAME (type, i), stream);
|
||||
fputs_filtered (": ", stream);
|
||||
}
|
||||
|
||||
val_print (TYPE_FIELD_TYPE (type, i),
|
||||
valaddr,
|
||||
embedded_offset + TYPE_FIELD_BITPOS (type, i) / 8,
|
||||
address,
|
||||
stream, recurse + 1, val, &opts,
|
||||
current_language);
|
||||
}
|
||||
|
||||
if (options->prettyformat)
|
||||
{
|
||||
fputs_filtered ("\n", stream);
|
||||
print_spaces_filtered (2 * recurse, stream);
|
||||
}
|
||||
|
||||
if (is_tuple || is_tuple_struct)
|
||||
fputs_filtered (")", stream);
|
||||
else
|
||||
fputs_filtered ("}", stream);
|
||||
}
|
||||
val_print_struct (type, valaddr, embedded_offset, address, stream,
|
||||
recurse, val, options);
|
||||
break;
|
||||
|
||||
default:
|
||||
|
|
@ -722,6 +766,72 @@ rust_val_print (struct type *type, const gdb_byte *valaddr, int embedded_offset,
|
|||
|
||||
|
||||
|
||||
static void
|
||||
rust_print_type (struct type *type, const char *varstring,
|
||||
struct ui_file *stream, int show, int level,
|
||||
const struct type_print_options *flags);
|
||||
|
||||
/* Print a struct or union typedef. */
|
||||
static void
|
||||
rust_print_struct_def (struct type *type, const char *varstring,
|
||||
struct ui_file *stream, int show, int level,
|
||||
const struct type_print_options *flags)
|
||||
{
|
||||
int is_tuple_struct, i;
|
||||
|
||||
/* Print a tuple type simply. */
|
||||
if (rust_tuple_type_p (type))
|
||||
{
|
||||
fputs_filtered (TYPE_TAG_NAME (type), stream);
|
||||
return;
|
||||
}
|
||||
|
||||
/* If we see a base class, delegate to C. */
|
||||
if (TYPE_N_BASECLASSES (type) > 0)
|
||||
c_print_type (type, varstring, stream, show, level, flags);
|
||||
|
||||
/* This code path is also used by unions. */
|
||||
if (TYPE_CODE (type) == TYPE_CODE_STRUCT)
|
||||
fputs_filtered ("struct ", stream);
|
||||
else
|
||||
fputs_filtered ("union ", stream);
|
||||
|
||||
if (TYPE_TAG_NAME (type) != NULL)
|
||||
fputs_filtered (TYPE_TAG_NAME (type), stream);
|
||||
|
||||
is_tuple_struct = rust_tuple_struct_type_p (type);
|
||||
|
||||
if (TYPE_NFIELDS (type) == 0 && !rust_tuple_type_p (type))
|
||||
return;
|
||||
fputs_filtered (is_tuple_struct ? " (\n" : " {\n", stream);
|
||||
|
||||
for (i = 0; i < TYPE_NFIELDS (type); ++i)
|
||||
{
|
||||
const char *name;
|
||||
|
||||
QUIT;
|
||||
if (field_is_static (&TYPE_FIELD (type, i)))
|
||||
continue;
|
||||
|
||||
/* We'd like to print "pub" here as needed, but rustc
|
||||
doesn't emit the debuginfo, and our types don't have
|
||||
cplus_struct_type attached. */
|
||||
|
||||
/* For a tuple struct we print the type but nothing
|
||||
else. */
|
||||
print_spaces_filtered (level + 2, stream);
|
||||
if (!is_tuple_struct)
|
||||
fprintf_filtered (stream, "%s: ", TYPE_FIELD_NAME (type, i));
|
||||
|
||||
rust_print_type (TYPE_FIELD_TYPE (type, i), NULL,
|
||||
stream, show - 1, level + 2,
|
||||
flags);
|
||||
fputs_filtered (",\n", stream);
|
||||
}
|
||||
|
||||
fprintfi_filtered (level, stream, is_tuple_struct ? ")" : "}");
|
||||
}
|
||||
|
||||
/* la_print_typedef implementation for Rust. */
|
||||
|
||||
static void
|
||||
|
|
@ -810,56 +920,7 @@ rust_print_type (struct type *type, const char *varstring,
|
|||
break;
|
||||
|
||||
case TYPE_CODE_STRUCT:
|
||||
{
|
||||
int is_tuple_struct;
|
||||
|
||||
/* Print a tuple type simply. */
|
||||
if (rust_tuple_type_p (type))
|
||||
{
|
||||
fputs_filtered (TYPE_TAG_NAME (type), stream);
|
||||
break;
|
||||
}
|
||||
|
||||
/* If we see a base class, delegate to C. */
|
||||
if (TYPE_N_BASECLASSES (type) > 0)
|
||||
goto c_printer;
|
||||
|
||||
fputs_filtered ("struct ", stream);
|
||||
if (TYPE_TAG_NAME (type) != NULL)
|
||||
fputs_filtered (TYPE_TAG_NAME (type), stream);
|
||||
|
||||
is_tuple_struct = rust_tuple_struct_type_p (type);
|
||||
|
||||
if (TYPE_NFIELDS (type) == 0 && !rust_tuple_type_p (type))
|
||||
break;
|
||||
fputs_filtered (is_tuple_struct ? " (\n" : " {\n", stream);
|
||||
|
||||
for (i = 0; i < TYPE_NFIELDS (type); ++i)
|
||||
{
|
||||
const char *name;
|
||||
|
||||
QUIT;
|
||||
if (field_is_static (&TYPE_FIELD (type, i)))
|
||||
continue;
|
||||
|
||||
/* We'd like to print "pub" here as needed, but rustc
|
||||
doesn't emit the debuginfo, and our types don't have
|
||||
cplus_struct_type attached. */
|
||||
|
||||
/* For a tuple struct we print the type but nothing
|
||||
else. */
|
||||
print_spaces_filtered (level + 2, stream);
|
||||
if (!is_tuple_struct)
|
||||
fprintf_filtered (stream, "%s: ", TYPE_FIELD_NAME (type, i));
|
||||
|
||||
rust_print_type (TYPE_FIELD_TYPE (type, i), NULL,
|
||||
stream, show - 1, level + 2,
|
||||
flags);
|
||||
fputs_filtered (",\n", stream);
|
||||
}
|
||||
|
||||
fprintfi_filtered (level, stream, is_tuple_struct ? ")" : "}");
|
||||
}
|
||||
rust_print_struct_def (type, varstring, stream, show, level, flags);
|
||||
break;
|
||||
|
||||
case TYPE_CODE_ENUM:
|
||||
|
|
@ -900,6 +961,16 @@ rust_print_type (struct type *type, const char *varstring,
|
|||
/* Skip the discriminant field. */
|
||||
int skip_to = 1;
|
||||
|
||||
/* Unions and structs have the same syntax in Rust,
|
||||
the only difference is that structs are declared with `struct`
|
||||
and union with `union`. This difference is handled in the struct
|
||||
printer. */
|
||||
if (rust_union_is_untagged (type))
|
||||
{
|
||||
rust_print_struct_def (type, varstring, stream, show, level, flags);
|
||||
break;
|
||||
}
|
||||
|
||||
fputs_filtered ("enum ", stream);
|
||||
if (TYPE_TAG_NAME (type) != NULL)
|
||||
{
|
||||
|
|
@ -1638,7 +1709,10 @@ rust_evaluate_subexp (struct type *expect_type, struct expression *exp,
|
|||
lhs = evaluate_subexp (NULL_TYPE, exp, pos, noside);
|
||||
|
||||
type = value_type (lhs);
|
||||
if (TYPE_CODE (type) == TYPE_CODE_UNION)
|
||||
/* Untagged unions can't have anonymous field access since
|
||||
they can only have named fields. */
|
||||
if (TYPE_CODE (type) == TYPE_CODE_UNION
|
||||
&& !rust_union_is_untagged (type))
|
||||
{
|
||||
struct cleanup *cleanup;
|
||||
|
||||
|
|
@ -1713,8 +1787,8 @@ tuple structs, and tuple-like enum variants"));
|
|||
lhs = evaluate_subexp (NULL_TYPE, exp, pos, noside);
|
||||
|
||||
type = value_type (lhs);
|
||||
|
||||
if (TYPE_CODE (type) == TYPE_CODE_UNION)
|
||||
if (TYPE_CODE (type) == TYPE_CODE_UNION
|
||||
&& !rust_union_is_untagged (type))
|
||||
{
|
||||
int i, start;
|
||||
struct disr_info disr;
|
||||
|
|
@ -1763,6 +1837,7 @@ which has only anonymous fields"),
|
|||
}
|
||||
else
|
||||
{
|
||||
/* Field access in structs and untagged unions works like C. */
|
||||
*pos = pc;
|
||||
result = evaluate_subexp_standard (expect_type, exp, pos, noside);
|
||||
}
|
||||
|
|
|
|||
Loading…
Reference in New Issue