Remove now-unused Rust evaluator code

Now that the Rust parser has switched to the new style, there is no
need for the old Rust evaluation code.

gdb/ChangeLog
2021-03-08  Tom Tromey  <tom@tromey.com>

	* rust-lang.h (class rust_language) <expression_ops,
	exp_descriptor_tab>: Remove.
	* rust-lang.c (rust_evaluate_funcall): Remove.
	(rust_range, rust_subscript, eval_op_rust_complement): Don't use
	EVAL_SKIP.
	(rust_evaluate_subexp): Remove.
	(rust_aggregate_operation::evaluate): Don't use EVAL_SKIP.
	(rust_operator_length, rust_dump_subexp_body, rust_print_subexp)
	(rust_operator_check, rust_language::exp_descriptor_tab): Remove.
This commit is contained in:
Tom Tromey
2021-03-08 07:27:57 -07:00
parent 08a057e64b
commit aa1da9ed50
3 changed files with 13 additions and 516 deletions

View File

@ -963,82 +963,6 @@ rust_slice_type (const char *name, struct type *elt_type,
/* A helper for rust_evaluate_subexp that handles OP_FUNCALL. */
static struct value *
rust_evaluate_funcall (struct expression *exp, int *pos, enum noside noside)
{
int i;
int num_args = exp->elts[*pos + 1].longconst;
const char *method;
struct value *function, *result, *arg0;
struct type *type, *fn_type;
const struct block *block;
struct block_symbol sym;
/* For an ordinary function call we can simply defer to the
generic implementation. */
if (exp->elts[*pos + 3].opcode != STRUCTOP_STRUCT)
return evaluate_subexp_standard (NULL, exp, pos, noside);
/* Skip over the OP_FUNCALL and the STRUCTOP_STRUCT. */
*pos += 4;
method = &exp->elts[*pos + 1].string;
*pos += 3 + BYTES_TO_EXP_ELEM (exp->elts[*pos].longconst + 1);
/* Evaluate the argument to STRUCTOP_STRUCT, then find its
type in order to look up the method. */
arg0 = evaluate_subexp (nullptr, exp, pos, noside);
if (noside == EVAL_SKIP)
{
for (i = 0; i < num_args; ++i)
evaluate_subexp (nullptr, exp, pos, noside);
return arg0;
}
std::vector<struct value *> args (num_args + 1);
args[0] = arg0;
/* We don't yet implement real Deref semantics. */
while (value_type (args[0])->code () == TYPE_CODE_PTR)
args[0] = value_ind (args[0]);
type = value_type (args[0]);
if ((type->code () != TYPE_CODE_STRUCT
&& type->code () != TYPE_CODE_UNION
&& type->code () != TYPE_CODE_ENUM)
|| rust_tuple_type_p (type))
error (_("Method calls only supported on struct or enum types"));
if (type->name () == NULL)
error (_("Method call on nameless type"));
std::string name = std::string (type->name ()) + "::" + method;
block = get_selected_block (0);
sym = lookup_symbol (name.c_str (), block, VAR_DOMAIN, NULL);
if (sym.symbol == NULL)
error (_("Could not find function named '%s'"), name.c_str ());
fn_type = SYMBOL_TYPE (sym.symbol);
if (fn_type->num_fields () == 0)
error (_("Function '%s' takes no arguments"), name.c_str ());
if (fn_type->field (0).type ()->code () == TYPE_CODE_PTR)
args[0] = value_addr (args[0]);
function = address_of_variable (sym.symbol, block);
for (i = 0; i < num_args; ++i)
args[i + 1] = evaluate_subexp (nullptr, exp, pos, noside);
if (noside == EVAL_AVOID_SIDE_EFFECTS)
result = value_zero (TYPE_TARGET_TYPE (fn_type), not_lval);
else
result = call_function_by_hand (function, NULL, args);
return result;
}
/* A helper for rust_evaluate_subexp that handles OP_RANGE. */
struct value *
@ -1055,9 +979,6 @@ rust_range (struct type *expect_type, struct expression *exp,
bool inclusive = !(kind & RANGE_HIGH_BOUND_EXCLUSIVE);
if (noside == EVAL_SKIP)
return value_from_longest (builtin_type (exp->gdbarch)->builtin_int, 1);
if (low == NULL)
{
if (high == NULL)
@ -1181,9 +1102,6 @@ rust_subscript (struct type *expect_type, struct expression *exp,
LONGEST high = 0;
int want_slice = 0;
if (noside == EVAL_SKIP)
return lhs;
rhstype = check_typedef (value_type (rhs));
if (rust_range_type_p (rhstype))
{
@ -1347,11 +1265,6 @@ eval_op_rust_complement (struct type *expect_type, struct expression *exp,
enum exp_opcode opcode,
struct value *value)
{
if (noside == EVAL_SKIP)
{
/* Preserving the type is enough. */
return value;
}
if (value_type (value)->code () == TYPE_CODE_BOOL)
return value_from_longest (value_type (value), value_logical_not (value));
return value_complement (value);
@ -1502,204 +1415,6 @@ eval_op_rust_structop (struct type *expect_type, struct expression *exp,
return result;
}
/* evaluate_exp implementation for Rust. */
static struct value *
rust_evaluate_subexp (struct type *expect_type, struct expression *exp,
int *pos, enum noside noside)
{
struct value *result;
enum exp_opcode op = exp->elts[*pos].opcode;
switch (op)
{
case UNOP_IND:
{
if (noside != EVAL_NORMAL)
result = evaluate_subexp_standard (expect_type, exp, pos, noside);
else
{
++*pos;
struct value *value = evaluate_subexp (expect_type, exp, pos,
noside);
result = eval_op_rust_ind (expect_type, exp, noside, op, value);
}
}
break;
case UNOP_COMPLEMENT:
{
struct value *value;
++*pos;
value = evaluate_subexp (nullptr, exp, pos, noside);
result = eval_op_rust_complement (expect_type, exp, noside, op, value);
}
break;
case BINOP_SUBSCRIPT:
{
++*pos;
struct value *lhs = evaluate_subexp (nullptr, exp, pos, noside);
struct value *rhs = evaluate_subexp (nullptr, exp, pos, noside);
result = rust_subscript (expect_type, exp, noside, false, lhs, rhs);
}
break;
case OP_FUNCALL:
result = rust_evaluate_funcall (exp, pos, noside);
break;
case OP_AGGREGATE:
{
int pc = (*pos)++;
struct type *type = exp->elts[pc + 1].type;
int arglen = longest_to_int (exp->elts[pc + 2].longconst);
int i;
CORE_ADDR addr = 0;
struct value *addrval = NULL;
*pos += 3;
if (noside == EVAL_NORMAL)
{
addrval = value_allocate_space_in_inferior (TYPE_LENGTH (type));
addr = value_as_long (addrval);
result = value_at_lazy (type, addr);
}
if (arglen > 0 && exp->elts[*pos].opcode == OP_OTHERS)
{
struct value *init;
++*pos;
init = rust_evaluate_subexp (NULL, exp, pos, noside);
if (noside == EVAL_NORMAL)
{
/* This isn't quite right but will do for the time
being, seeing that we can't implement the Copy
trait anyway. */
value_assign (result, init);
}
--arglen;
}
gdb_assert (arglen % 2 == 0);
for (i = 0; i < arglen; i += 2)
{
int len;
const char *fieldname;
struct value *value, *field;
gdb_assert (exp->elts[*pos].opcode == OP_NAME);
++*pos;
len = longest_to_int (exp->elts[*pos].longconst);
++*pos;
fieldname = &exp->elts[*pos].string;
*pos += 2 + BYTES_TO_EXP_ELEM (len + 1);
value = rust_evaluate_subexp (NULL, exp, pos, noside);
if (noside == EVAL_NORMAL)
{
field = value_struct_elt (&result, NULL, fieldname, NULL,
"structure");
value_assign (field, value);
}
}
if (noside == EVAL_SKIP)
return value_from_longest (builtin_type (exp->gdbarch)->builtin_int,
1);
else if (noside == EVAL_AVOID_SIDE_EFFECTS)
result = allocate_value (type);
else
result = value_at_lazy (type, addr);
}
break;
case OP_RUST_ARRAY:
{
(*pos)++;
struct value *elt;
struct value *ncopies;
elt = rust_evaluate_subexp (NULL, exp, pos, noside);
ncopies = rust_evaluate_subexp (NULL, exp, pos, noside);
return eval_op_rust_array (expect_type, exp, noside, op, elt, ncopies);
}
break;
case STRUCTOP_ANONYMOUS:
{
/* Anonymous field access, i.e. foo.1. */
struct value *lhs;
int pc, field_number;
pc = (*pos)++;
field_number = longest_to_int (exp->elts[pc + 1].longconst);
(*pos) += 2;
lhs = evaluate_subexp (nullptr, exp, pos, noside);
return eval_op_rust_struct_anon (expect_type, exp, noside,
field_number, lhs);
}
break;
case STRUCTOP_STRUCT:
{
struct value *lhs;
int tem, pc;
pc = (*pos)++;
tem = longest_to_int (exp->elts[pc + 1].longconst);
(*pos) += 3 + BYTES_TO_EXP_ELEM (tem + 1);
lhs = evaluate_subexp (nullptr, exp, pos, noside);
const char *field_name = &exp->elts[pc + 2].string;
return eval_op_rust_structop (expect_type, exp, noside, lhs,
field_name);
}
break;
case OP_RANGE:
{
struct value *low = NULL, *high = NULL;
auto kind
= (enum range_flag) longest_to_int (exp->elts[*pos + 1].longconst);
*pos += 3;
if (!(kind & RANGE_LOW_BOUND_DEFAULT))
low = evaluate_subexp (nullptr, exp, pos, noside);
if (!(kind & RANGE_HIGH_BOUND_DEFAULT))
high = evaluate_subexp (nullptr, exp, pos, noside);
result = rust_range (expect_type, exp, noside, kind, low, high);
}
break;
case UNOP_ADDR:
/* We might have &array[range], in which case we need to make a
slice. */
if (exp->elts[*pos + 1].opcode == BINOP_SUBSCRIPT)
{
++*pos;
++*pos;
struct value *lhs = evaluate_subexp (nullptr, exp, pos, noside);
struct value *rhs = evaluate_subexp (nullptr, exp, pos, noside);
result = rust_subscript (expect_type, exp, noside, true, lhs, rhs);
break;
}
/* Fall through. */
default:
result = evaluate_subexp_standard (expect_type, exp, pos, noside);
break;
}
return result;
}
namespace expr
{
@ -1746,9 +1461,7 @@ rust_aggregate_operation::evaluate (struct type *expect_type,
}
}
if (noside == EVAL_SKIP)
result = value_from_longest (builtin_type (exp->gdbarch)->builtin_int, 1);
else if (noside == EVAL_AVOID_SIDE_EFFECTS)
if (noside == EVAL_AVOID_SIDE_EFFECTS)
result = allocate_value (type);
else
result = value_at_lazy (type, addr);
@ -1808,226 +1521,8 @@ rust_structop::evaluate_funcall (struct type *expect_type,
}
/* operator_length implementation for Rust. */
static void
rust_operator_length (const struct expression *exp, int pc, int *oplenp,
int *argsp)
{
int oplen = 1;
int args = 0;
switch (exp->elts[pc - 1].opcode)
{
case OP_AGGREGATE:
/* We handle aggregate as a type and argument count. The first
argument might be OP_OTHERS. After that the arguments
alternate: first an OP_NAME, then an expression. */
oplen = 4;
args = longest_to_int (exp->elts[pc - 2].longconst);
break;
case OP_OTHERS:
oplen = 1;
args = 1;
break;
case STRUCTOP_ANONYMOUS:
oplen = 3;
args = 1;
break;
case OP_RUST_ARRAY:
oplen = 1;
args = 2;
break;
default:
operator_length_standard (exp, pc, oplenp, argsp);
return;
}
*oplenp = oplen;
*argsp = args;
}
/* dump_subexp_body implementation for Rust. */
static int
rust_dump_subexp_body (struct expression *exp, struct ui_file *stream,
int elt)
{
switch (exp->elts[elt].opcode)
{
case OP_AGGREGATE:
{
int length = longest_to_int (exp->elts[elt + 2].longconst);
int i;
fprintf_filtered (stream, "Type @");
gdb_print_host_address (exp->elts[elt + 1].type, stream);
fprintf_filtered (stream, " (");
type_print (exp->elts[elt + 1].type, NULL, stream, 0);
fprintf_filtered (stream, "), length %d", length);
elt += 4;
for (i = 0; i < length; ++i)
elt = dump_subexp (exp, stream, elt);
}
break;
case OP_STRING:
case OP_NAME:
{
LONGEST len = exp->elts[elt + 1].longconst;
fprintf_filtered (stream, "%s: %s",
(exp->elts[elt].opcode == OP_STRING
? "string" : "name"),
&exp->elts[elt + 2].string);
elt += 4 + BYTES_TO_EXP_ELEM (len + 1);
}
break;
case OP_OTHERS:
elt = dump_subexp (exp, stream, elt + 1);
break;
case STRUCTOP_ANONYMOUS:
{
int field_number;
field_number = longest_to_int (exp->elts[elt + 1].longconst);
fprintf_filtered (stream, "Field number: %d", field_number);
elt = dump_subexp (exp, stream, elt + 3);
}
break;
case OP_RUST_ARRAY:
++elt;
break;
default:
elt = dump_subexp_body_standard (exp, stream, elt);
break;
}
return elt;
}
/* print_subexp implementation for Rust. */
static void
rust_print_subexp (struct expression *exp, int *pos, struct ui_file *stream,
enum precedence prec)
{
switch (exp->elts[*pos].opcode)
{
case OP_AGGREGATE:
{
int length = longest_to_int (exp->elts[*pos + 2].longconst);
int i;
type_print (exp->elts[*pos + 1].type, "", stream, 0);
fputs_filtered (" { ", stream);
*pos += 4;
for (i = 0; i < length; ++i)
{
rust_print_subexp (exp, pos, stream, prec);
fputs_filtered (", ", stream);
}
fputs_filtered (" }", stream);
}
break;
case OP_NAME:
{
LONGEST len = exp->elts[*pos + 1].longconst;
fputs_filtered (&exp->elts[*pos + 2].string, stream);
*pos += 4 + BYTES_TO_EXP_ELEM (len + 1);
}
break;
case OP_OTHERS:
{
fputs_filtered ("<<others>> (", stream);
++*pos;
rust_print_subexp (exp, pos, stream, prec);
fputs_filtered (")", stream);
}
break;
case STRUCTOP_ANONYMOUS:
{
int tem = longest_to_int (exp->elts[*pos + 1].longconst);
(*pos) += 3;
print_subexp (exp, pos, stream, PREC_SUFFIX);
fprintf_filtered (stream, ".%d", tem);
}
break;
case OP_RUST_ARRAY:
++*pos;
fprintf_filtered (stream, "[");
rust_print_subexp (exp, pos, stream, prec);
fprintf_filtered (stream, "; ");
rust_print_subexp (exp, pos, stream, prec);
fprintf_filtered (stream, "]");
break;
default:
print_subexp_standard (exp, pos, stream, prec);
break;
}
}
/* operator_check implementation for Rust. */
static int
rust_operator_check (struct expression *exp, int pos,
int (*objfile_func) (struct objfile *objfile,
void *data),
void *data)
{
switch (exp->elts[pos].opcode)
{
case OP_AGGREGATE:
{
struct type *type = exp->elts[pos + 1].type;
struct objfile *objfile = type->objfile_owner ();
if (objfile != NULL && (*objfile_func) (objfile, data))
return 1;
}
break;
case OP_OTHERS:
case OP_NAME:
case OP_RUST_ARRAY:
break;
default:
return operator_check_standard (exp, pos, objfile_func, data);
}
return 0;
}
const struct exp_descriptor rust_language::exp_descriptor_tab =
{
rust_print_subexp,
rust_operator_length,
rust_operator_check,
rust_dump_subexp_body,
rust_evaluate_subexp
};
/* See language.h. */
void