/* Rust expression parsing for GDB, the GNU debugger.
Copyright (C) 2016-2023 Free Software Foundation, Inc.
This file is part of GDB.
This program 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 3 of the License, or
(at your option) any later version.
This program 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 this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "block.h"
#include "charset.h"
#include "cp-support.h"
#include "gdbsupport/gdb_obstack.h"
#include "gdbsupport/gdb_regex.h"
#include "rust-lang.h"
#include "parser-defs.h"
#include "gdbsupport/selftest.h"
#include "value.h"
#include "gdbarch.h"
#include "rust-exp.h"
using namespace expr;
/* A regular expression for matching Rust numbers. This is split up
since it is very long and this gives us a way to comment the
sections. */
static const char number_regex_text[] =
/* subexpression 1: allows use of alternation, otherwise uninteresting */
"^("
/* First comes floating point. */
/* Recognize number after the decimal point, with optional
exponent and optional type suffix.
subexpression 2: allows "?", otherwise uninteresting
subexpression 3: if present, type suffix
*/
"[0-9][0-9_]*\\.[0-9][0-9_]*([eE][-+]?[0-9][0-9_]*)?(f32|f64)?"
#define FLOAT_TYPE1 3
"|"
/* Recognize exponent without decimal point, with optional type
suffix.
subexpression 4: if present, type suffix
*/
#define FLOAT_TYPE2 4
"[0-9][0-9_]*[eE][-+]?[0-9][0-9_]*(f32|f64)?"
"|"
/* "23." is a valid floating point number, but "23.e5" and
"23.f32" are not. So, handle the trailing-. case
separately. */
"[0-9][0-9_]*\\."
"|"
/* Finally come integers.
subexpression 5: text of integer
subexpression 6: if present, type suffix
subexpression 7: allows use of alternation, otherwise uninteresting
*/
#define INT_TEXT 5
#define INT_TYPE 6
"(0x[a-fA-F0-9_]+|0o[0-7_]+|0b[01_]+|[0-9][0-9_]*)"
"([iu](size|8|16|32|64|128))?"
")";
/* The number of subexpressions to allocate space for, including the
"0th" whole match subexpression. */
#define NUM_SUBEXPRESSIONS 8
/* The compiled number-matching regex. */
static regex_t number_regex;
/* The kinds of tokens. Note that single-character tokens are
represented by themselves, so for instance '[' is a token. */
enum token_type : int
{
/* Make sure to start after any ASCII character. */
GDBVAR = 256,
IDENT,
COMPLETE,
INTEGER,
DECIMAL_INTEGER,
STRING,
BYTESTRING,
FLOAT,
COMPOUND_ASSIGN,
/* Keyword tokens. */
KW_AS,
KW_IF,
KW_TRUE,
KW_FALSE,
KW_SUPER,
KW_SELF,
KW_MUT,
KW_EXTERN,
KW_CONST,
KW_FN,
KW_SIZEOF,
/* Operator tokens. */
DOTDOT,
DOTDOTEQ,
OROR,
ANDAND,
EQEQ,
NOTEQ,
LTEQ,
GTEQ,
LSH,
RSH,
COLONCOLON,
ARROW,
};
/* A typed integer constant. */
struct typed_val_int
{
gdb_mpz val;
struct type *type;
};
/* A typed floating point constant. */
struct typed_val_float
{
float_data val;
struct type *type;
};
/* A struct of this type is used to describe a token. */
struct token_info
{
const char *name;
int value;
enum exp_opcode opcode;
};
/* Identifier tokens. */
static const struct token_info identifier_tokens[] =
{
{ "as", KW_AS, OP_NULL },
{ "false", KW_FALSE, OP_NULL },
{ "if", 0, OP_NULL },
{ "mut", KW_MUT, OP_NULL },
{ "const", KW_CONST, OP_NULL },
{ "self", KW_SELF, OP_NULL },
{ "super", KW_SUPER, OP_NULL },
{ "true", KW_TRUE, OP_NULL },
{ "extern", KW_EXTERN, OP_NULL },
{ "fn", KW_FN, OP_NULL },
{ "sizeof", KW_SIZEOF, OP_NULL },
};
/* Operator tokens, sorted longest first. */
static const struct token_info operator_tokens[] =
{
{ ">>=", COMPOUND_ASSIGN, BINOP_RSH },
{ "<<=", COMPOUND_ASSIGN, BINOP_LSH },
{ "<<", LSH, OP_NULL },
{ ">>", RSH, OP_NULL },
{ "&&", ANDAND, OP_NULL },
{ "||", OROR, OP_NULL },
{ "==", EQEQ, OP_NULL },
{ "!=", NOTEQ, OP_NULL },
{ "<=", LTEQ, OP_NULL },
{ ">=", GTEQ, OP_NULL },
{ "+=", COMPOUND_ASSIGN, BINOP_ADD },
{ "-=", COMPOUND_ASSIGN, BINOP_SUB },
{ "*=", COMPOUND_ASSIGN, BINOP_MUL },
{ "/=", COMPOUND_ASSIGN, BINOP_DIV },
{ "%=", COMPOUND_ASSIGN, BINOP_REM },
{ "&=", COMPOUND_ASSIGN, BINOP_BITWISE_AND },
{ "|=", COMPOUND_ASSIGN, BINOP_BITWISE_IOR },
{ "^=", COMPOUND_ASSIGN, BINOP_BITWISE_XOR },
{ "..=", DOTDOTEQ, OP_NULL },
{ "::", COLONCOLON, OP_NULL },
{ "..", DOTDOT, OP_NULL },
{ "->", ARROW, OP_NULL }
};
/* An instance of this is created before parsing, and destroyed when
parsing is finished. */
struct rust_parser
{
explicit rust_parser (struct parser_state *state)
: pstate (state)
{
}
DISABLE_COPY_AND_ASSIGN (rust_parser);
/* Return the parser's language. */
const struct language_defn *language () const
{
return pstate->language ();
}
/* Return the parser's gdbarch. */
struct gdbarch *arch () const
{
return pstate->gdbarch ();
}
/* A helper to look up a Rust type, or fail. This only works for
types defined by rust_language_arch_info. */
struct type *get_type (const char *name)
{
struct type *type;
type = language_lookup_primitive_type (language (), arch (), name);
if (type == NULL)
error (_("Could not find Rust type %s"), name);
return type;
}
std::string crate_name (const std::string &name);
std::string super_name (const std::string &ident, unsigned int n_supers);
int lex_character ();
int lex_number ();
int lex_string ();
int lex_identifier ();
uint32_t lex_hex (int min, int max);
uint32_t lex_escape (int is_byte);
int lex_operator ();
int lex_one_token ();
void push_back (char c);
/* The main interface to lexing. Lexes one token and updates the
internal state. */
void lex ()
{
current_token = lex_one_token ();
}
/* Assuming the current token is TYPE, lex the next token. */
void assume (int type)
{
gdb_assert (current_token == type);
lex ();
}
/* Require the single-character token C, and lex the next token; or
throw an exception. */
void require (char type)
{
if (current_token != type)
error (_("'%c' expected"), type);
lex ();
}
/* Entry point for all parsing. */
operation_up parse_entry_point ()
{
lex ();
operation_up result = parse_expr ();
if (current_token != 0)
error (_("Syntax error near '%s'"), pstate->prev_lexptr);
return result;
}
operation_up parse_tuple ();
operation_up parse_array ();
operation_up name_to_operation (const std::string &name);
operation_up parse_struct_expr (struct type *type);
operation_up parse_binop (bool required);
operation_up parse_range ();
operation_up parse_expr ();
operation_up parse_sizeof ();
operation_up parse_addr ();
operation_up parse_field (operation_up &&);
operation_up parse_index (operation_up &&);
std::vector<operation_up> parse_paren_args ();
operation_up parse_call (operation_up &&);
std::vector<struct type *> parse_type_list ();
std::vector<struct type *> parse_maybe_type_list ();
struct type *parse_array_type ();
struct type *parse_slice_type ();
struct type *parse_pointer_type ();
struct type *parse_function_type ();
struct type *parse_tuple_type ();
struct type *parse_type ();
std::string parse_path (bool for_expr);
operation_up parse_string ();
operation_up parse_tuple_struct (struct type *type);
operation_up parse_path_expr ();
operation_up parse_atom (bool required);
void update_innermost_block (struct block_symbol sym);
struct block_symbol lookup_symbol (const char *name,
const struct block *block,
const domain_enum domain);
struct type *rust_lookup_type (const char *name);
/* Clear some state. This is only used for testing. */
#if GDB_SELF_TEST
void reset (const char *input)
{
pstate->prev_lexptr = nullptr;
pstate->lexptr = input;
paren_depth = 0;
current_token = 0;
current_int_val = {};
current_float_val = {};
current_string_val = {};
current_opcode = OP_NULL;
}
#endif /* GDB_SELF_TEST */
/* Return the token's string value as a string. */
std::string get_string () const
{
return std::string (current_string_val.ptr, current_string_val.length);
}
/* A pointer to this is installed globally. */
auto_obstack obstack;
/* The parser state gdb gave us. */
struct parser_state *pstate;
/* Depth of parentheses. */
int paren_depth = 0;
/* The current token's type. */
int current_token = 0;
/* The current token's payload, if any. */
typed_val_int current_int_val {};
typed_val_float current_float_val {};
struct stoken current_string_val {};
enum exp_opcode current_opcode = OP_NULL;
/* When completing, this may be set to the field operation to
complete. */
operation_up completion_op;
};
/* Return an string referring to NAME, but relative to the crate's
name. */
std::string
rust_parser::crate_name (const std::string &name)
{
std::string crate = rust_crate_for_block (pstate->expression_context_block);
if (crate.empty ())
error (_("Could not find crate for current location"));
return "::" + crate + "::" + name;
}
/* Return a string referring to a "super::" qualified name. IDENT is
the base name and N_SUPERS is how many "super::"s were provided.
N_SUPERS can be zero. */
std::string
rust_parser::super_name (const std::string &ident, unsigned int n_supers)
{
const char *scope = "";
if (pstate->expression_context_block != nullptr)
scope = pstate->expression_context_block->scope ();
int offset;
if (scope[0] == '\0')
error (_("Couldn't find namespace scope for self::"));
if (n_supers > 0)
{
int len;
std::vector<int> offsets;
unsigned int current_len;
current_len = cp_find_first_component (scope);
while (scope[current_len] != '\0')
{
offsets.push_back (current_len);
gdb_assert (scope[current_len] == ':');
/* The "::". */
current_len += 2;
current_len += cp_find_first_component (scope
+ current_len);
}
len = offsets.size ();
if (n_supers >= len)
error (_("Too many super:: uses from '%s'"), scope);
offset = offsets[len - n_supers];
}
else
offset = strlen (scope);
return "::" + std::string (scope, offset) + "::" + ident;
}
/* A helper to appropriately munge NAME and BLOCK depending on the
presence of a leading "::". */
static void
munge_name_and_block (const char **name, const struct block **block)
{
/* If it is a global reference, skip the current block in favor of
the static block. */
if (startswith (*name, "::"))
{
*name += 2;
*block = (*block)->static_block ();
}
}
/* Like lookup_symbol, but handles Rust namespace conventions, and
doesn't require field_of_this_result. */
struct block_symbol
rust_parser::lookup_symbol (const char *name, const struct block *block,
const domain_enum domain)
{
struct block_symbol result;
munge_name_and_block (&name, &block);
result = ::lookup_symbol (name, block, domain, NULL);
if (result.symbol != NULL)
update_innermost_block (result);
return result;
}
/* Look up a type, following Rust namespace conventions. */
struct type *
rust_parser::rust_lookup_type (const char *name)
{
struct block_symbol result;
struct type *type;
const struct block *block = pstate->expression_context_block;
munge_name_and_block (&name, &block);
result = ::lookup_symbol (name, block, STRUCT_DOMAIN, NULL);
if (result.symbol != NULL)
{
update_innermost_block (result);
return result.symbol->type ();
}
type = lookup_typename (language (), name, NULL, 1);
if (type != NULL)
return type;
/* Last chance, try a built-in type. */
return language_lookup_primitive_type (language (), arch (), name);
}
/* A helper that updates the innermost block as appropriate. */
void
rust_parser::update_innermost_block (struct block_symbol sym)
{
if (symbol_read_needs_frame (sym.symbol))
pstate->block_tracker->update (sym);
}
/* Lex a hex number with at least MIN digits and at most MAX
digits. */
uint32_t
rust_parser::lex_hex (int min, int max)
{
uint32_t result = 0;
int len = 0;
/* We only want to stop at MAX if we're lexing a byte escape. */
int check_max = min == max;
while ((check_max ? len <= max : 1)
&& ((pstate->lexptr[0] >= 'a' && pstate->lexptr[0] <= 'f')
|| (pstate->lexptr[0] >= 'A' && pstate->lexptr[0] <= 'F')
|| (pstate->lexptr[0] >= '0' && pstate->lexptr[0] <= '9')))
{
result *= 16;
if (pstate->lexptr[0] >= 'a' && pstate->lexptr[0] <= 'f')
result = result + 10 + pstate->lexptr[0] - 'a';
else if (pstate->lexptr[0] >= 'A' && pstate->lexptr[0] <= 'F')
result = result + 10 + pstate->lexptr[0] - 'A';
else
result = result + pstate->lexptr[0] - '0';
++pstate->lexptr;
++len;
}
if (len < min)
error (_("Not enough hex digits seen"));
if (len > max)
{
gdb_assert (min != max);
error (_("Overlong hex escape"));
}
return result;
}
/* Lex an escape. IS_BYTE is true if we're lexing a byte escape;
otherwise we're lexing a character escape. */
uint32_t
rust_parser::lex_escape (int is_byte)
{
uint32_t result;
gdb_assert (pstate->lexptr[0] == '\\');
++pstate->lexptr;
switch (pstate->lexptr[0])
{
case 'x':
++pstate->lexptr;
result = lex_hex (2, 2);
break;
case 'u':
if (is_byte)
error (_("Unicode escape in byte literal"));
++pstate->lexptr;
if (pstate->lexptr[0] != '{')
error (_("Missing '{' in Unicode escape"));
++pstate->lexptr;
result = lex_hex (1, 6);
/* Could do range checks here. */
if (pstate->lexptr[0] != '}')
error (_("Missing '}' in Unicode escape"));
++pstate->lexptr;
break;
case 'n':
result = '\n';
++pstate->lexptr;
break;
case 'r':
result = '\r';
++pstate->lexptr;
break;
case 't':
result = '\t';
++pstate->lexptr;
break;
case '\\':
result = '\\';
++pstate->lexptr;
break;
case '0':
result = '\0';
++pstate->lexptr;
break;
case '\'':
result = '\'';
++pstate->lexptr;
break;
case '"':
result = '"';
++pstate->lexptr;
break;
default:
error (_("Invalid escape \\%c in literal"), pstate->lexptr[0]);
}
return result;
}
/* A helper for lex_character. Search forward for the closing single
quote, then convert the bytes from the host charset to UTF-32. */
static uint32_t
lex_multibyte_char (const char *text, int *len)
{
/* Only look a maximum of 5 bytes for the closing quote. This is
the maximum for UTF-8. */
int quote;
gdb_assert (text[0] != '\'');
for (quote = 1; text[quote] != '\0' && text[quote] != '\''; ++quote)
;
*len = quote;
/* The caller will issue an error. */
if (text[quote] == '\0')
return 0;
auto_obstack result;
convert_between_encodings (host_charset (), HOST_UTF32,
(const gdb_byte *) text,
quote, 1, &result, translit_none);
int size = obstack_object_size (&result);
if (size > 4)
error (_("overlong character literal"));
uint32_t value;
memcpy (&value, obstack_finish (&result), size);
return value;
}
/* Lex a character constant. */
int
rust_parser::lex_character ()
{
int is_byte = 0;
uint32_t value;
if (pstate->lexptr[0] == 'b')
{
is_byte = 1;
++pstate->lexptr;
}
gdb_assert (pstate->lexptr[0] == '\'');
++pstate->lexptr;
if (pstate->lexptr[0] == '\'')
error (_("empty character literal"));
else if (pstate->lexptr[0] == '\\')
value = lex_escape (is_byte);
else
{
int len;
value = lex_multibyte_char (&pstate->lexptr[0], &len);
pstate->lexptr += len;
}
if (pstate->lexptr[0] != '\'')
error (_("Unterminated character literal"));
++pstate->lexptr;
current_int_val.val = value;
current_int_val.type = get_type (is_byte ? "u8" : "char");
return INTEGER;
}
/* Return the offset of the double quote if STR looks like the start
of a raw string, or 0 if STR does not start a raw string. */
static int
starts_raw_string (const char *str)
{
const char *save = str;
if (str[0] != 'r')
return 0;
++str;
while (str[0] == '#')
++str;
if (str[0] == '"')
return str - save;
return 0;
}
/* Return true if STR looks like the end of a raw string that had N
hashes at the start. */
static bool
ends_raw_string (const char *str, int n)
{
int i;
gdb_assert (str[0] == '"');
for (i = 0; i < n; ++i)
if (str[i + 1] != '#')
return false;
return true;
}
/* Lex a string constant. */
int
rust_parser::lex_string ()
{
int is_byte = pstate->lexptr[0] == 'b';
int raw_length;
if (is_byte)
++pstate->lexptr;
raw_length = starts_raw_string (pstate->lexptr);
pstate->lexptr += raw_length;
gdb_assert (pstate->lexptr[0] == '"');
++pstate->lexptr;
while (1)
{
uint32_t value;
if (raw_length > 0)
{
if (pstate->lexptr[0] == '"' && ends_raw_string (pstate->lexptr,
raw_length - 1))
{
/* Exit with lexptr pointing after the final "#". */
pstate->lexptr += raw_length;
break;
}
else if (pstate->lexptr[0] == '\0')
error (_("Unexpected EOF in string"));
value = pstate->lexptr[0] & 0xff;
if (is_byte && value > 127)
error (_("Non-ASCII value in raw byte string"));
obstack_1grow (&obstack, value);
++pstate->lexptr;
}
else if (pstate->lexptr[0] == '"')
{
/* Make sure to skip the quote. */
++pstate->lexptr;
break;
}
else if (pstate->lexptr[0] == '\\')
{
value = lex_escape (is_byte);
if (is_byte)
obstack_1grow (&obstack, value);
else
convert_between_encodings (HOST_UTF32, "UTF-8",
(gdb_byte *) &value,
sizeof (value), sizeof (value),
&obstack, translit_none);
}
else if (pstate->lexptr[0] == '\0')
error (_("Unexpected EOF in string"));
else
{
value = pstate->lexptr[0] & 0xff;
if (is_byte && value > 127)
error (_("Non-ASCII value in byte string"));
obstack_1grow (&obstack, value);
++pstate->lexptr;
}
}
current_string_val.length = obstack_object_size (&obstack);
current_string_val.ptr = (const char *) obstack_finish (&obstack);
return is_byte ? BYTESTRING : STRING;
}
/* Return true if STRING starts with whitespace followed by a digit. */
static bool
space_then_number (const char *string)
{
const char *p = string;
while (p[0] == ' ' || p[0] == '\t')
++p;
if (p == string)
return false;
return *p >= '0' && *p <= '9';
}
/* Return true if C can start an identifier. */
static bool
rust_identifier_start_p (char c)
{
return ((c >= 'a' && c <= 'z')
|| (c >= 'A' && c <= 'Z')
|| c == '_'
|| c == '$'
/* Allow any non-ASCII character as an identifier. There
doesn't seem to be a need to be picky about this. */
|| (c & 0x80) != 0);
}
/* Lex an identifier. */
int
rust_parser::lex_identifier ()
{
unsigned int length;
const struct token_info *token;
int is_gdb_var = pstate->lexptr[0] == '$';
bool is_raw = false;
if (pstate->lexptr[0] == 'r'
&& pstate->lexptr[1] == '#'
&& rust_identifier_start_p (pstate->lexptr[2]))
{
is_raw = true;
pstate->lexptr += 2;
}
const char *start = pstate->lexptr;
gdb_assert (rust_identifier_start_p (pstate->lexptr[0]));
++pstate->lexptr;
/* Allow any non-ASCII character here. This "handles" UTF-8 by
passing it through. */
while ((pstate->lexptr[0] >= 'a' && pstate->lexptr[0] <= 'z')
|| (pstate->lexptr[0] >= 'A' && pstate->lexptr[0] <= 'Z')
|| pstate->lexptr[0] == '_'
|| (is_gdb_var && pstate->lexptr[0] == '$')
|| (pstate->lexptr[0] >= '0' && pstate->lexptr[0] <= '9')
|| (pstate->lexptr[0] & 0x80) != 0)
++pstate->lexptr;
length = pstate->lexptr - start;
token = NULL;
if (!is_raw)
{
for (const auto &candidate : identifier_tokens)
{
if (length == strlen (candidate.name)
&& strncmp (candidate.name, start, length) == 0)
{
token = &candidate;
break;
}
}
}
if (token != NULL)
{
if (token->value == 0)
{
/* Leave the terminating token alone. */
pstate->lexptr = start;
return 0;
}
}
else if (token == NULL
&& !is_raw
&& (strncmp (start, "thread", length) == 0
|| strncmp (start, "task", length) == 0)
&& space_then_number (pstate->lexptr))
{
/* "task" or "thread" followed by a number terminates the
parse, per gdb rules. */
pstate->lexptr = start;
return 0;
}
if (token == NULL || (pstate->parse_completion && pstate->lexptr[0] == '\0'))
{
current_string_val.length = length;
current_string_val.ptr = start;
}
if (pstate->parse_completion && pstate->lexptr[0] == '\0')
{
/* Prevent rustyylex from returning two COMPLETE tokens. */
pstate->prev_lexptr = pstate->lexptr;
return COMPLETE;
}
if (token != NULL)
return token->value;
if (is_gdb_var)
return GDBVAR;
return IDENT;
}
/* Lex an operator. */
int
rust_parser::lex_operator ()
{
const struct token_info *token = NULL;
for (const auto &candidate : operator_tokens)
{
if (strncmp (candidate.name, pstate->lexptr,
strlen (candidate.name)) == 0)
{
pstate->lexptr += strlen (candidate.name);
token = &candidate;
break;
}
}
if (token != NULL)
{
current_opcode = token->opcode;
return token->value;
}
return *pstate->lexptr++;
}
/* Lex a number. */
int
rust_parser::lex_number ()
{
regmatch_t subexps[NUM_SUBEXPRESSIONS];
int match;
int is_integer = 0;
int could_be_decimal = 1;
int implicit_i32 = 0;
const char *type_name = NULL;
struct type *type;
int end_index;
int type_index = -1;
int i;
match = regexec (&number_regex, pstate->lexptr, ARRAY_SIZE (subexps),
subexps, 0);
/* Failure means the regexp is broken. */
gdb_assert (match == 0);
if (subexps[INT_TEXT].rm_so != -1)
{
/* Integer part matched. */
is_integer = 1;
end_index = subexps[INT_TEXT].rm_eo;
if (subexps[INT_TYPE].rm_so == -1)
{
type_name = "i32";
implicit_i32 = 1;
}
else
{
type_index = INT_TYPE;
could_be_decimal = 0;
}
}
else if (subexps[FLOAT_TYPE1].rm_so != -1)
{
/* Found floating point type suffix. */
end_index = subexps[FLOAT_TYPE1].rm_so;
type_index = FLOAT_TYPE1;
}
else if (subexps[FLOAT_TYPE2].rm_so != -1)
{
/* Found floating point type suffix. */
end_index = subexps[FLOAT_TYPE2].rm_so;
type_index = FLOAT_TYPE2;
}
else
{
/* Any other floating point match. */
end_index = subexps[0].rm_eo;
type_name = "f64";
}
/* We need a special case if the final character is ".". In this
case we might need to parse an integer. For example, "23.f()" is
a request for a trait method call, not a syntax error involving
the floating point number "23.". */
gdb_assert (subexps[0].rm_eo > 0);
if (pstate->lexptr[subexps[0].rm_eo - 1] == '.')
{
const char *next = skip_spaces (&pstate->lexptr[subexps[0].rm_eo]);
if (rust_identifier_start_p (*next) || *next == '.')
{
--subexps[0].rm_eo;
is_integer = 1;
end_index = subexps[0].rm_eo;
type_name = "i32";
could_be_decimal = 1;
implicit_i32 = 1;
}
}
/* Compute the type name if we haven't already. */
std::string type_name_holder;
if (type_name == NULL)
{
gdb_assert (type_index != -1);
type_name_holder = std::string ((pstate->lexptr
+ subexps[type_index].rm_so),
(subexps[type_index].rm_eo
- subexps[type_index].rm_so));
type_name = type_name_holder.c_str ();
}
/* Look up the type. */
type = get_type (type_name);
/* Copy the text of the number and remove the "_"s. */
std::string number;
for (i = 0; i < end_index && pstate->lexptr[i]; ++i)
{
if (pstate->lexptr[i] == '_')
could_be_decimal = 0;
else
number.push_back (pstate->lexptr[i]);
}
/* Advance past the match. */
pstate->lexptr += subexps[0].rm_eo;
/* Parse the number. */
if (is_integer)
{
int radix = 10;
int offset = 0;
if (number[0] == '0')
{
if (number[1] == 'x')
radix = 16;
else if (number[1] == 'o')
radix = 8;
else if (number[1] == 'b')
radix = 2;
if (radix != 10)
{
offset = 2;
could_be_decimal = 0;
}
}
if (!current_int_val.val.set (number.c_str () + offset, radix))
{
/* Shouldn't be possible. */
error (_("Invalid integer"));
}
if (implicit_i32)
{
static gdb_mpz sixty_three_bit = gdb_mpz::pow (2, 63);
static gdb_mpz thirty_one_bit = gdb_mpz::pow (2, 31);
if (current_int_val.val >= sixty_three_bit)
type = get_type ("i128");
else if (current_int_val.val >= thirty_one_bit)
type = get_type ("i64");
}
current_int_val.type = type;
}
else
{
current_float_val.type = type;
bool parsed = parse_float (number.c_str (), number.length (),
current_float_val.type,
current_float_val.val.data ());
gdb_assert (parsed);
}
return is_integer ? (could_be_decimal ? DECIMAL_INTEGER : INTEGER) : FLOAT;
}
/* The lexer. */
int
rust_parser::lex_one_token ()
{
/* Skip all leading whitespace. */
while (pstate->lexptr[0] == ' '
|| pstate->lexptr[0] == '\t'
|| pstate->lexptr[0] == '\r'
|| pstate->lexptr[0] == '\n')
++pstate->lexptr;
/* If we hit EOF and we're completing, then return COMPLETE -- maybe
we're completing an empty string at the end of a field_expr.
But, we don't want to return two COMPLETE tokens in a row. */
if (pstate->lexptr[0] == '\0' && pstate->lexptr == pstate->prev_lexptr)
return 0;
pstate->prev_lexptr = pstate->lexptr;
if (pstate->lexptr[0] == '\0')
{
if (pstate->parse_completion)
{
current_string_val.length =0;
current_string_val.ptr = "";
return COMPLETE;
}
return 0;
}
if (pstate->lexptr[0] >= '0' && pstate->lexptr[0] <= '9')
return lex_number ();
else if (pstate->lexptr[0] == 'b' && pstate->lexptr[1] == '\'')
return lex_character ();
else if (pstate->lexptr[0] == 'b' && pstate->lexptr[1] == '"')
return lex_string ();
else if (pstate->lexptr[0] == 'b' && starts_raw_string (pstate->lexptr + 1))
return lex_string ();
else if (starts_raw_string (pstate->lexptr))
return lex_string ();
else if (rust_identifier_start_p (pstate->lexptr[0]))
return lex_identifier ();
else if (pstate->lexptr[0] == '"')
return lex_string ();
else if (pstate->lexptr[0] == '\'')
return lex_character ();
else if (pstate->lexptr[0] == '}' || pstate->lexptr[0] == ']')
{
/* Falls through to lex_operator. */
--paren_depth;
}
else if (pstate->lexptr[0] == '(' || pstate->lexptr[0] == '{')
{
/* Falls through to lex_operator. */
++paren_depth;
}
else if (pstate->lexptr[0] == ',' && pstate->comma_terminates
&& paren_depth == 0)
return 0;
return lex_operator ();
}
/* Push back a single character to be re-lexed. */
void
rust_parser::push_back (char c)
{
/* Can't be called before any lexing. */
gdb_assert (pstate->prev_lexptr != NULL);
--pstate->lexptr;
gdb_assert (*pstate->lexptr == c);
}
/* Parse a tuple or paren expression. */
operation_up
rust_parser::parse_tuple ()
{
assume ('(');
if (current_token == ')')
{
lex ();
struct type *unit = get_type ("()");
return make_operation<long_const_operation> (unit, 0);
}
operation_up expr = parse_expr ();
if (current_token == ')')
{
/* Parenthesized expression. */
lex ();
return make_operation<rust_parenthesized_operation> (std::move (expr));
}
std::vector<operation_up> ops;
ops.push_back (std::move (expr));
while (current_token != ')')
{
if (current_token != ',')
error (_("',' or ')' expected"));
lex ();
/* A trailing "," is ok. */
if (current_token != ')')
ops.push_back (parse_expr ());
}
assume (')');
error (_("Tuple expressions not supported yet"));
}
/* Parse an array expression. */
operation_up
rust_parser::parse_array ()
{
assume ('[');
if (current_token == KW_MUT)
lex ();
operation_up result;
operation_up expr = parse_expr ();
if (current_token == ';')
{
lex ();
operation_up rhs = parse_expr ();
result = make_operation<rust_array_operation> (std::move (expr),
std::move (rhs));
}
else if (current_token == ',' || current_token == ']')
{
std::vector<operation_up> ops;
ops.push_back (std::move (expr));
while (current_token != ']')
{
if (current_token != ',')
error (_("',' or ']' expected"));
lex ();
ops.push_back (parse_expr ());
}
ops.shrink_to_fit ();
int len = ops.size () - 1;
result = make_operation<array_operation> (0, len, std::move (ops));
}
else
error (_("',', ';', or ']' expected"));
require (']');
return result;
}
/* Turn a name into an operation. */
operation_up
rust_parser::name_to_operation (const std::string &name)
{
struct block_symbol sym = lookup_symbol (name.c_str (),
pstate->expression_context_block,
VAR_DOMAIN);
if (sym.symbol != nullptr && sym.symbol->aclass () != LOC_TYPEDEF)
return make_operation<var_value_operation> (sym);
struct type *type = nullptr;
if (sym.symbol != nullptr)
{
gdb_assert (sym.symbol->aclass () == LOC_TYPEDEF);
type = sym.symbol->type ();
}
if (type == nullptr)
type = rust_lookup_type (name.c_str ());
if (type == nullptr)
error (_("No symbol '%s' in current context"), name.c_str ());
if (type->code () == TYPE_CODE_STRUCT && type->num_fields () == 0)
{
/* A unit-like struct. */
operation_up result (new rust_aggregate_operation (type, {}, {}));
return result;
}
else
return make_operation<type_operation> (type);
}
/* Parse a struct expression. */
operation_up
rust_parser::parse_struct_expr (struct type *type)
{
assume ('{');
if (type->code () != TYPE_CODE_STRUCT
|| rust_tuple_type_p (type)
|| rust_tuple_struct_type_p (type))
error (_("Struct expression applied to non-struct type"));
std::vector<std::pair<std::string, operation_up>> field_v;
while (current_token != '}' && current_token != DOTDOT)
{
if (current_token != IDENT)
error (_("'}', '..', or identifier expected"));
std::string name = get_string ();
lex ();
operation_up expr;
if (current_token == ',' || current_token == '}'
|| current_token == DOTDOT)
expr = name_to_operation (name);
else
{
require (':');
expr = parse_expr ();
}
field_v.emplace_back (std::move (name), std::move (expr));
/* A trailing "," is ok. */
if (current_token == ',')
lex ();
}
operation_up others;
if (current_token == DOTDOT)
{
lex ();
others = parse_expr ();
}
require ('}');
return make_operation<rust_aggregate_operation> (type,
std::move (others),
std::move (field_v));
}
/* Used by the operator precedence parser. */
struct rustop_item
{
rustop_item (int token_, int precedence_, enum exp_opcode opcode_,
operation_up &&op_)
: token (token_),
precedence (precedence_),
opcode (opcode_),
op (std::move (op_))
{
}
/* The token value. */
int token;
/* Precedence of this operator. */
int precedence;
/* This is used only for assign-modify. */
enum exp_opcode opcode;
/* The right hand side of this operation. */
operation_up op;
};
/* An operator precedence parser for binary operations, including
"as". */
operation_up
rust_parser::parse_binop (bool required)
{
/* All the binary operators. Each one is of the form
OPERATION(TOKEN, PRECEDENCE, TYPE)
TOKEN is the corresponding operator token.
PRECEDENCE is a value indicating relative precedence.
TYPE is the operation type corresponding to the operator.
Assignment operations are handled specially, not via this
table; they have precedence 0. */
#define ALL_OPS \
OPERATION ('*', 10, mul_operation) \
OPERATION ('/', 10, div_operation) \
OPERATION ('%', 10, rem_operation) \
OPERATION ('@', 9, repeat_operation) \
OPERATION ('+', 8, add_operation) \
OPERATION ('-', 8, sub_operation) \
OPERATION (LSH, 7, lsh_operation) \
OPERATION (RSH, 7, rsh_operation) \
OPERATION ('&', 6, bitwise_and_operation) \
OPERATION ('^', 5, bitwise_xor_operation) \
OPERATION ('|', 4, bitwise_ior_operation) \
OPERATION (EQEQ, 3, equal_operation) \
OPERATION (NOTEQ, 3, notequal_operation) \
OPERATION ('<', 3, less_operation) \
OPERATION (LTEQ, 3, leq_operation) \
OPERATION ('>', 3, gtr_operation) \
OPERATION (GTEQ, 3, geq_operation) \
OPERATION (ANDAND, 2, logical_and_operation) \
OPERATION (OROR, 1, logical_or_operation)
#define ASSIGN_PREC 0
operation_up start = parse_atom (required);
if (start == nullptr)
{
gdb_assert (!required);
return start;
}
std::vector<rustop_item> operator_stack;
operator_stack.emplace_back (0, -1, OP_NULL, std::move (start));
while (true)
{
int this_token = current_token;
enum exp_opcode compound_assign_op = OP_NULL;
int precedence = -2;
switch (this_token)
{
#define OPERATION(TOKEN, PRECEDENCE, TYPE) \
case TOKEN: \
precedence = PRECEDENCE; \
lex (); \
break;
ALL_OPS
#undef OPERATION
case COMPOUND_ASSIGN:
compound_assign_op = current_opcode;
/* FALLTHROUGH */
case '=':
precedence = ASSIGN_PREC;
lex ();
break;
/* "as" must be handled specially. */
case KW_AS:
{
lex ();
rustop_item &lhs = operator_stack.back ();
struct type *type = parse_type ();
lhs.op = make_operation<unop_cast_operation> (std::move (lhs.op),
type);
}
/* Bypass the rest of the loop. */
continue;
default:
/* Arrange to pop the entire stack. */
precedence = -2;
break;
}
/* Make sure that assignments are right-associative while other
operations are left-associative. */
while ((precedence == ASSIGN_PREC
? precedence < operator_stack.back ().precedence
: precedence <= operator_stack.back ().precedence)
&& operator_stack.size () > 1)
{
rustop_item rhs = std::move (operator_stack.back ());
operator_stack.pop_back ();
rustop_item &lhs = operator_stack.back ();
switch (rhs.token)
{
#define OPERATION(TOKEN, PRECEDENCE, TYPE) \
case TOKEN: \
lhs.op = make_operation<TYPE> (std::move (lhs.op), \
std::move (rhs.op)); \
break;
ALL_OPS
#undef OPERATION
case '=':
case COMPOUND_ASSIGN:
{
if (rhs.token == '=')
lhs.op = (make_operation<assign_operation>
(std::move (lhs.op), std::move (rhs.op)));
else
lhs.op = (make_operation<assign_modify_operation>
(rhs.opcode, std::move (lhs.op),
std::move (rhs.op)));
struct type *unit_type = get_type ("()");
operation_up nil (new long_const_operation (unit_type, 0));
lhs.op = (make_operation<comma_operation>
(std::move (lhs.op), std::move (nil)));
}
break;
default:
gdb_assert_not_reached ("bad binary operator");
}
}
if (precedence == -2)
break;
operator_stack.emplace_back (this_token, precedence, compound_assign_op,
parse_atom (true));
}
gdb_assert (operator_stack.size () == 1);
return std::move (operator_stack[0].op);
#undef ALL_OPS
}
/* Parse a range expression. */
operation_up
rust_parser::parse_range ()
{
enum range_flag kind = (RANGE_HIGH_BOUND_DEFAULT
| RANGE_LOW_BOUND_DEFAULT);
operation_up lhs;
if (current_token != DOTDOT && current_token != DOTDOTEQ)
{
lhs = parse_binop (true);
kind &= ~RANGE_LOW_BOUND_DEFAULT;
}
if (current_token == DOTDOT)
kind |= RANGE_HIGH_BOUND_EXCLUSIVE;
else if (current_token != DOTDOTEQ)
return lhs;
lex ();
/* A "..=" range requires a high bound, but otherwise it is
optional. */
operation_up rhs = parse_binop ((kind & RANGE_HIGH_BOUND_EXCLUSIVE) == 0);
if (rhs != nullptr)
kind &= ~RANGE_HIGH_BOUND_DEFAULT;
return make_operation<rust_range_operation> (kind,
std::move (lhs),
std::move (rhs));
}
/* Parse an expression. */
operation_up
rust_parser::parse_expr ()
{
return parse_range ();
}
/* Parse a sizeof expression. */
operation_up
rust_parser::parse_sizeof ()
{
assume (KW_SIZEOF);
require ('(');
operation_up result = make_operation<unop_sizeof_operation> (parse_expr ());
require (')');
return result;
}
/* Parse an address-of operation. */
operation_up
rust_parser::parse_addr ()
{
assume ('&');
if (current_token == KW_MUT)
lex ();
return make_operation<rust_unop_addr_operation> (parse_atom (true));
}
/* Parse a field expression. */
operation_up
rust_parser::parse_field (operation_up &&lhs)
{
assume ('.');
operation_up result;
switch (current_token)
{
case IDENT:
case COMPLETE:
{
bool is_complete = current_token == COMPLETE;
auto struct_op = new rust_structop (std::move (lhs), get_string ());
lex ();
if (is_complete)
{
completion_op.reset (struct_op);
pstate->mark_struct_expression (struct_op);
/* Throw to the outermost level of the parser. */
error (_("not really an error"));
}
result.reset (struct_op);
}
break;
case DECIMAL_INTEGER:
{
int idx = current_int_val.val.as_integer<int> ();
result = make_operation<rust_struct_anon> (idx, std::move (lhs));
lex ();
}
break;
case INTEGER:
error (_("'_' not allowed in integers in anonymous field references"));
default:
error (_("field name expected"));
}
return result;
}
/* Parse an index expression. */
operation_up
rust_parser::parse_index (operation_up &&lhs)
{
assume ('[');
operation_up rhs = parse_expr ();
require (']');
return make_operation<rust_subscript_operation> (std::move (lhs),
std::move (rhs));
}
/* Parse a sequence of comma-separated expressions in parens. */
std::vector<operation_up>
rust_parser::parse_paren_args ()
{
assume ('(');
std::vector<operation_up> args;
while (current_token != ')')
{
if (!args.empty ())
{
if (current_token != ',')
error (_("',' or ')' expected"));
lex ();
}
args.push_back (parse_expr ());
}
assume (')');
return args;
}
/* Parse the parenthesized part of a function call. */
operation_up
rust_parser::parse_call (operation_up &&lhs)
{
std::vector<operation_up> args = parse_paren_args ();
return make_operation<funcall_operation> (std::move (lhs),
std::move (args));
}
/* Parse a list of types. */
std::vector<struct type *>
rust_parser::parse_type_list ()
{
std::vector<struct type *> result;
result.push_back (parse_type ());
while (current_token == ',')
{
lex ();
result.push_back (parse_type ());
}
return result;
}
/* Parse a possibly-empty list of types, surrounded in parens. */
std::vector<struct type *>
rust_parser::parse_maybe_type_list ()
{
assume ('(');
std::vector<struct type *> types;
if (current_token != ')')
types = parse_type_list ();
require (')');
return types;
}
/* Parse an array type. */
struct type *
rust_parser::parse_array_type ()
{
assume ('[');
struct type *elt_type = parse_type ();
require (';');
if (current_token != INTEGER && current_token != DECIMAL_INTEGER)
error (_("integer expected"));
ULONGEST val = current_int_val.val.as_integer<ULONGEST> ();
lex ();
require (']');
return lookup_array_range_type (elt_type, 0, val - 1);
}
/* Parse a slice type. */
struct type *
rust_parser::parse_slice_type ()
{
assume ('&');
/* Handle &str specially. This is an important type in Rust. While
the compiler does emit the "&str" type in the DWARF, just "str"
itself isn't always available -- but it's handy if this works
seamlessly. */
if (current_token == IDENT && get_string () == "str")
{
lex ();
return rust_slice_type ("&str", get_type ("u8"), get_type ("usize"));
}
bool is_slice = current_token == '[';
if (is_slice)
lex ();
struct type *target = parse_type ();
if (is_slice)
{
require (']');
return rust_slice_type ("&[*gdb*]", target, get_type ("usize"));
}
/* For now we treat &x and *x identically. */
return lookup_pointer_type (target);
}
/* Parse a pointer type. */
struct type *
rust_parser::parse_pointer_type ()
{
assume ('*');
if (current_token == KW_MUT || current_token == KW_CONST)
lex ();
struct type *target = parse_type ();
/* For the time being we ignore mut/const. */
return lookup_pointer_type (target);
}
/* Parse a function type. */
struct type *
rust_parser::parse_function_type ()
{
assume (KW_FN);
if (current_token != '(')
error (_("'(' expected"));
std::vector<struct type *> types = parse_maybe_type_list ();
if (current_token != ARROW)
error (_("'->' expected"));
lex ();
struct type *result_type = parse_type ();
struct type **argtypes = nullptr;
if (!types.empty ())
argtypes = types.data ();
result_type = lookup_function_type_with_arguments (result_type,
types.size (),
argtypes);
return lookup_pointer_type (result_type);
}
/* Parse a tuple type. */
struct type *
rust_parser::parse_tuple_type ()
{
std::vector<struct type *> types = parse_maybe_type_list ();
auto_obstack obstack;
obstack_1grow (&obstack, '(');
for (int i = 0; i < types.size (); ++i)
{
std::string type_name = type_to_string (types[i]);
if (i > 0)
obstack_1grow (&obstack, ',');
obstack_grow_str (&obstack, type_name.c_str ());
}
obstack_grow_str0 (&obstack, ")");
const char *name = (const char *) obstack_finish (&obstack);
/* We don't allow creating new tuple types (yet), but we do allow
looking up existing tuple types. */
struct type *result = rust_lookup_type (name);
if (result == nullptr)
error (_("could not find tuple type '%s'"), name);
return result;
}
/* Parse a type. */
struct type *
rust_parser::parse_type ()
{
switch (current_token)
{
case '[':
return parse_array_type ();
case '&':
return parse_slice_type ();
case '*':
return parse_pointer_type ();
case KW_FN:
return parse_function_type ();
case '(':
return parse_tuple_type ();
case KW_SELF:
case KW_SUPER:
case COLONCOLON:
case KW_EXTERN:
case IDENT:
{
std::string path = parse_path (false);
struct type *result = rust_lookup_type (path.c_str ());
if (result == nullptr)
error (_("No type name '%s' in current context"), path.c_str ());
return result;
}
default:
error (_("type expected"));
}
}
/* Parse a path. */
std::string
rust_parser::parse_path (bool for_expr)
{
unsigned n_supers = 0;
int first_token = current_token;
switch (current_token)
{
case KW_SELF:
lex ();
if (current_token != COLONCOLON)
return "self";
lex ();
/* FALLTHROUGH */
case KW_SUPER:
while (current_token == KW_SUPER)
{
++n_supers;
lex ();
if (current_token != COLONCOLON)
error (_("'::' expected"));
lex ();
}
break;
case COLONCOLON:
lex ();
break;
case KW_EXTERN:
/* This is a gdb extension to make it possible to refer to items
in other crates. It just bypasses adding the current crate
to the front of the name. */
lex ();
break;
}
if (current_token != IDENT)
error (_("identifier expected"));
std::string path = get_string ();
bool saw_ident = true;
lex ();
/* The condition here lets us enter the loop even if we see
"ident<...>". */
while (current_token == COLONCOLON || current_token == '<')
{
if (current_token == COLONCOLON)
{
lex ();
saw_ident = false;
if (current_token == IDENT)
{
path = path + "::" + get_string ();
lex ();
saw_ident = true;
}
else if (current_token == COLONCOLON)
{
/* The code below won't detect this scenario. */
error (_("unexpected '::'"));
}
}
if (current_token != '<')
continue;
/* Expression use name::<...>, whereas types use name<...>. */
if (for_expr)
{
/* Expressions use "name::<...>", so if we saw an identifier
after the "::", we ignore the "<" here. */
if (saw_ident)
break;
}
else
{
/* Types use "name<...>", so we need to have seen the
identifier. */
if (!saw_ident)
break;
}
lex ();
std::vector<struct type *> types = parse_type_list ();
if (current_token == '>')
lex ();
else if (current_token == RSH)
{
push_back ('>');
lex ();
}
else
error (_("'>' expected"));
path += "<";
for (int i = 0; i < types.size (); ++i)
{
if (i > 0)
path += ",";
path += type_to_string (types[i]);
}
path += ">";
break;
}
switch (first_token)
{
case KW_SELF:
case KW_SUPER:
return super_name (path, n_supers);
case COLONCOLON:
return crate_name (path);
case KW_EXTERN:
return "::" + path;
case IDENT:
return path;
default:
gdb_assert_not_reached ("missing case in path parsing");
}
}
/* Handle the parsing for a string expression. */
operation_up
rust_parser::parse_string ()
{
gdb_assert (current_token == STRING);
/* Wrap the raw string in the &str struct. */
struct type *type = rust_lookup_type ("&str");
if (type == nullptr)
error (_("Could not find type '&str'"));
std::vector<std::pair<std::string, operation_up>> field_v;
size_t len = current_string_val.length;
operation_up str = make_operation<string_operation> (get_string ());
operation_up addr
= make_operation<rust_unop_addr_operation> (std::move (str));
field_v.emplace_back ("data_ptr", std::move (addr));
struct type *valtype = get_type ("usize");
operation_up lenop = make_operation<long_const_operation> (valtype, len);
field_v.emplace_back ("length", std::move (lenop));
return make_operation<rust_aggregate_operation> (type,
operation_up (),
std::move (field_v));
}
/* Parse a tuple struct expression. */
operation_up
rust_parser::parse_tuple_struct (struct type *type)
{
std::vector<operation_up> args = parse_paren_args ();
std::vector<std::pair<std::string, operation_up>> field_v (args.size ());
for (int i = 0; i < args.size (); ++i)
field_v[i] = { string_printf ("__%d", i), std::move (args[i]) };
return (make_operation<rust_aggregate_operation>
(type, operation_up (), std::move (field_v)));
}
/* Parse a path expression. */
operation_up
rust_parser::parse_path_expr ()
{
std::string path = parse_path (true);
if (current_token == '{')
{
struct type *type = rust_lookup_type (path.c_str ());
if (type == nullptr)
error (_("Could not find type '%s'"), path.c_str ());
return parse_struct_expr (type);
}
else if (current_token == '(')
{
struct type *type = rust_lookup_type (path.c_str ());
/* If this is actually a tuple struct expression, handle it
here. If it is a call, it will be handled elsewhere. */
if (type != nullptr)
{
if (!rust_tuple_struct_type_p (type))
error (_("Type %s is not a tuple struct"), path.c_str ());
return parse_tuple_struct (type);
}
}
return name_to_operation (path);
}
/* Parse an atom. "Atom" isn't a Rust term, but this refers to a
single unitary item in the grammar; but here including some unary
prefix and postfix expressions. */
operation_up
rust_parser::parse_atom (bool required)
{
operation_up result;
switch (current_token)
{
case '(':
result = parse_tuple ();
break;
case '[':
result = parse_array ();
break;
case INTEGER:
case DECIMAL_INTEGER:
result = make_operation<long_const_operation> (current_int_val.type,
current_int_val.val);
lex ();
break;
case FLOAT:
result = make_operation<float_const_operation> (current_float_val.type,
current_float_val.val);
lex ();
break;
case STRING:
result = parse_string ();
lex ();
break;
case BYTESTRING:
result = make_operation<string_operation> (get_string ());
lex ();
break;
case KW_TRUE:
case KW_FALSE:
result = make_operation<bool_operation> (current_token == KW_TRUE);
lex ();
break;
case GDBVAR:
/* This is kind of a hacky approach. */
{
pstate->push_dollar (current_string_val);
result = pstate->pop ();
lex ();
}
break;
case KW_SELF:
case KW_SUPER:
case COLONCOLON:
case KW_EXTERN:
case IDENT:
result = parse_path_expr ();
break;
case '*':
lex ();
result = make_operation<rust_unop_ind_operation> (parse_atom (true));
break;
case '+':
lex ();
result = make_operation<unary_plus_operation> (parse_atom (true));
break;
case '-':
lex ();
result = make_operation<unary_neg_operation> (parse_atom (true));
break;
case '!':
lex ();
result = make_operation<rust_unop_compl_operation> (parse_atom (true));
break;
case KW_SIZEOF:
result = parse_sizeof ();
break;
case '&':
result = parse_addr ();
break;
default:
if (!required)
return {};
error (_("unexpected token"));
}
/* Now parse suffixes. */
while (true)
{
switch (current_token)
{
case '.':
result = parse_field (std::move (result));
break;
case '[':
result = parse_index (std::move (result));
break;
case '(':
result = parse_call (std::move (result));
break;
default:
return result;
}
}
}
/* The parser as exposed to gdb. */
int
rust_language::parser (struct parser_state *state) const
{
rust_parser parser (state);
operation_up result;
try
{
result = parser.parse_entry_point ();
}
catch (const gdb_exception &exc)
{
if (state->parse_completion)
{
result = std::move (parser.completion_op);
if (result == nullptr)
throw;
}
else
throw;
}
state->set_operation (std::move (result));
return 0;
}
#if GDB_SELF_TEST
/* A test helper that lexes a string, expecting a single token. */
static void
rust_lex_test_one (rust_parser *parser, const char *input, int expected)
{
int token;
parser->reset (input);
token = parser->lex_one_token ();
SELF_CHECK (token == expected);
if (token)
{
token = parser->lex_one_token ();
SELF_CHECK (token == 0);
}
}
/* Test that INPUT lexes as the integer VALUE. */
static void
rust_lex_int_test (rust_parser *parser, const char *input,
ULONGEST value, int kind)
{
rust_lex_test_one (parser, input, kind);
SELF_CHECK (parser->current_int_val.val == value);
}
/* Test that INPUT throws an exception with text ERR. */
static void
rust_lex_exception_test (rust_parser *parser, const char *input,
const char *err)
{
try
{
/* The "kind" doesn't matter. */
rust_lex_test_one (parser, input, DECIMAL_INTEGER);
SELF_CHECK (0);
}
catch (const gdb_exception_error &except)
{
SELF_CHECK (strcmp (except.what (), err) == 0);
}
}
/* Test that INPUT lexes as the identifier, string, or byte-string
VALUE. KIND holds the expected token kind. */
static void
rust_lex_stringish_test (rust_parser *parser, const char *input,
const char *value, int kind)
{
rust_lex_test_one (parser, input, kind);
SELF_CHECK (parser->get_string () == value);
}
/* Helper to test that a string parses as a given token sequence. */
static void
rust_lex_test_sequence (rust_parser *parser, const char *input, int len,
const int expected[])
{
int i;
parser->reset (input);
for (i = 0; i < len; ++i)
{
int token = parser->lex_one_token ();
SELF_CHECK (token == expected[i]);
}
}
/* Tests for an integer-parsing corner case. */
static void
rust_lex_test_trailing_dot (rust_parser *parser)
{
const int expected1[] = { DECIMAL_INTEGER, '.', IDENT, '(', ')', 0 };
const int expected2[] = { INTEGER, '.', IDENT, '(', ')', 0 };
const int expected3[] = { FLOAT, EQEQ, '(', ')', 0 };
const int expected4[] = { DECIMAL_INTEGER, DOTDOT, DECIMAL_INTEGER, 0 };
rust_lex_test_sequence (parser, "23.g()", ARRAY_SIZE (expected1), expected1);
rust_lex_test_sequence (parser, "23_0.g()", ARRAY_SIZE (expected2),
expected2);
rust_lex_test_sequence (parser, "23.==()", ARRAY_SIZE (expected3),
expected3);
rust_lex_test_sequence (parser, "23..25", ARRAY_SIZE (expected4), expected4);
}
/* Tests of completion. */
static void
rust_lex_test_completion (rust_parser *parser)
{
const int expected[] = { IDENT, '.', COMPLETE, 0 };
parser->pstate->parse_completion = 1;
rust_lex_test_sequence (parser, "something.wha", ARRAY_SIZE (expected),
expected);
rust_lex_test_sequence (parser, "something.", ARRAY_SIZE (expected),
expected);
parser->pstate->parse_completion = 0;
}
/* Test pushback. */
static void
rust_lex_test_push_back (rust_parser *parser)
{
int token;
parser->reset (">>=");
token = parser->lex_one_token ();
SELF_CHECK (token == COMPOUND_ASSIGN);
SELF_CHECK (parser->current_opcode == BINOP_RSH);
parser->push_back ('=');
token = parser->lex_one_token ();
SELF_CHECK (token == '=');
token = parser->lex_one_token ();
SELF_CHECK (token == 0);
}
/* Unit test the lexer. */
static void
rust_lex_tests (void)
{
/* Set up dummy "parser", so that rust_type works. */
struct parser_state ps (language_def (language_rust), target_gdbarch (),
nullptr, 0, 0, nullptr, 0, nullptr);
rust_parser parser (&ps);
rust_lex_test_one (&parser, "", 0);
rust_lex_test_one (&parser, " \t \n \r ", 0);
rust_lex_test_one (&parser, "thread 23", 0);
rust_lex_test_one (&parser, "task 23", 0);
rust_lex_test_one (&parser, "th 104", 0);
rust_lex_test_one (&parser, "ta 97", 0);
rust_lex_int_test (&parser, "'z'", 'z', INTEGER);
rust_lex_int_test (&parser, "'\\xff'", 0xff, INTEGER);
rust_lex_int_test (&parser, "'\\u{1016f}'", 0x1016f, INTEGER);
rust_lex_int_test (&parser, "b'z'", 'z', INTEGER);
rust_lex_int_test (&parser, "b'\\xfe'", 0xfe, INTEGER);
rust_lex_int_test (&parser, "b'\\xFE'", 0xfe, INTEGER);
rust_lex_int_test (&parser, "b'\\xfE'", 0xfe, INTEGER);
/* Test all escapes in both modes. */
rust_lex_int_test (&parser, "'\\n'", '\n', INTEGER);
rust_lex_int_test (&parser, "'\\r'", '\r', INTEGER);
rust_lex_int_test (&parser, "'\\t'", '\t', INTEGER);
rust_lex_int_test (&parser, "'\\\\'", '\\', INTEGER);
rust_lex_int_test (&parser, "'\\0'", '\0', INTEGER);
rust_lex_int_test (&parser, "'\\''", '\'', INTEGER);
rust_lex_int_test (&parser, "'\\\"'", '"', INTEGER);
rust_lex_int_test (&parser, "b'\\n'", '\n', INTEGER);
rust_lex_int_test (&parser, "b'\\r'", '\r', INTEGER);
rust_lex_int_test (&parser, "b'\\t'", '\t', INTEGER);
rust_lex_int_test (&parser, "b'\\\\'", '\\', INTEGER);
rust_lex_int_test (&parser, "b'\\0'", '\0', INTEGER);
rust_lex_int_test (&parser, "b'\\''", '\'', INTEGER);
rust_lex_int_test (&parser, "b'\\\"'", '"', INTEGER);
rust_lex_exception_test (&parser, "'z", "Unterminated character literal");
rust_lex_exception_test (&parser, "b'\\x0'", "Not enough hex digits seen");
rust_lex_exception_test (&parser, "b'\\u{0}'",
"Unicode escape in byte literal");
rust_lex_exception_test (&parser, "'\\x0'", "Not enough hex digits seen");
rust_lex_exception_test (&parser, "'\\u0'", "Missing '{' in Unicode escape");
rust_lex_exception_test (&parser, "'\\u{0", "Missing '}' in Unicode escape");
rust_lex_exception_test (&parser, "'\\u{0000007}", "Overlong hex escape");
rust_lex_exception_test (&parser, "'\\u{}", "Not enough hex digits seen");
rust_lex_exception_test (&parser, "'\\Q'", "Invalid escape \\Q in literal");
rust_lex_exception_test (&parser, "b'\\Q'", "Invalid escape \\Q in literal");
rust_lex_int_test (&parser, "23", 23, DECIMAL_INTEGER);
rust_lex_int_test (&parser, "2_344__29", 234429, INTEGER);
rust_lex_int_test (&parser, "0x1f", 0x1f, INTEGER);
rust_lex_int_test (&parser, "23usize", 23, INTEGER);
rust_lex_int_test (&parser, "23i32", 23, INTEGER);
rust_lex_int_test (&parser, "0x1_f", 0x1f, INTEGER);
rust_lex_int_test (&parser, "0b1_101011__", 0x6b, INTEGER);
rust_lex_int_test (&parser, "0o001177i64", 639, INTEGER);
rust_lex_int_test (&parser, "0x123456789u64", 0x123456789ull, INTEGER);
rust_lex_test_trailing_dot (&parser);
rust_lex_test_one (&parser, "23.", FLOAT);
rust_lex_test_one (&parser, "23.99f32", FLOAT);
rust_lex_test_one (&parser, "23e7", FLOAT);
rust_lex_test_one (&parser, "23E-7", FLOAT);
rust_lex_test_one (&parser, "23e+7", FLOAT);
rust_lex_test_one (&parser, "23.99e+7f64", FLOAT);
rust_lex_test_one (&parser, "23.82f32", FLOAT);
rust_lex_stringish_test (&parser, "hibob", "hibob", IDENT);
rust_lex_stringish_test (&parser, "hibob__93", "hibob__93", IDENT);
rust_lex_stringish_test (&parser, "thread", "thread", IDENT);
rust_lex_stringish_test (&parser, "r#true", "true", IDENT);
const int expected1[] = { IDENT, DECIMAL_INTEGER, 0 };
rust_lex_test_sequence (&parser, "r#thread 23", ARRAY_SIZE (expected1),
expected1);
const int expected2[] = { IDENT, '#', 0 };
rust_lex_test_sequence (&parser, "r#", ARRAY_SIZE (expected2), expected2);
rust_lex_stringish_test (&parser, "\"string\"", "string", STRING);
rust_lex_stringish_test (&parser, "\"str\\ting\"", "str\ting", STRING);
rust_lex_stringish_test (&parser, "\"str\\\"ing\"", "str\"ing", STRING);
rust_lex_stringish_test (&parser, "r\"str\\ing\"", "str\\ing", STRING);
rust_lex_stringish_test (&parser, "r#\"str\\ting\"#", "str\\ting", STRING);
rust_lex_stringish_test (&parser, "r###\"str\\\"ing\"###", "str\\\"ing",
STRING);
rust_lex_stringish_test (&parser, "b\"string\"", "string", BYTESTRING);
rust_lex_stringish_test (&parser, "b\"\x73tring\"", "string", BYTESTRING);
rust_lex_stringish_test (&parser, "b\"str\\\"ing\"", "str\"ing", BYTESTRING);
rust_lex_stringish_test (&parser, "br####\"\\x73tring\"####", "\\x73tring",
BYTESTRING);
for (const auto &candidate : identifier_tokens)
rust_lex_test_one (&parser, candidate.name, candidate.value);
for (const auto &candidate : operator_tokens)
rust_lex_test_one (&parser, candidate.name, candidate.value);
rust_lex_test_completion (&parser);
rust_lex_test_push_back (&parser);
}
#endif /* GDB_SELF_TEST */
void _initialize_rust_exp ();
void
_initialize_rust_exp ()
{
int code = regcomp (&number_regex, number_regex_text, REG_EXTENDED);
/* If the regular expression was incorrect, it was a programming
error. */
gdb_assert (code == 0);
#if GDB_SELF_TEST
selftests::register_test ("rust-lex", rust_lex_tests);
#endif
}