/gdb-7.4.50.20120714/gdb/go-exp.y
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Possible License(s): GPL-2.0, LGPL-2.0, GPL-3.0, LGPL-2.1
- /* YACC parser for Go expressions, for GDB.
- Copyright (C) 2012 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/>. */
- /* This file is derived from c-exp.y, p-exp.y. */
- /* Parse a Go expression from text in a string,
- and return the result as a struct expression pointer.
- That structure contains arithmetic operations in reverse polish,
- with constants represented by operations that are followed by special data.
- See expression.h for the details of the format.
- What is important here is that it can be built up sequentially
- during the process of parsing; the lower levels of the tree always
- come first in the result.
- Note that malloc's and realloc's in this file are transformed to
- xmalloc and xrealloc respectively by the same sed command in the
- makefile that remaps any other malloc/realloc inserted by the parser
- generator. Doing this with #defines and trying to control the interaction
- with include files (<malloc.h> and <stdlib.h> for example) just became
- too messy, particularly when such includes can be inserted at random
- times by the parser generator. */
- /* Known bugs or limitations:
- - Unicode
- - &^
- - '_' (blank identifier)
- - automatic deref of pointers
- - method expressions
- - interfaces, channels, etc.
- And lots of other things.
- I'm sure there's some cleanup to do.
- */
- %{
- #include "defs.h"
- #include "gdb_string.h"
- #include <ctype.h>
- #include "expression.h"
- #include "value.h"
- #include "parser-defs.h"
- #include "language.h"
- #include "c-lang.h"
- #include "go-lang.h"
- #include "bfd.h" /* Required by objfiles.h. */
- #include "symfile.h" /* Required by objfiles.h. */
- #include "objfiles.h" /* For have_full_symbols and have_partial_symbols */
- #include "charset.h"
- #include "block.h"
- #define parse_type builtin_type (parse_gdbarch)
- /* Remap normal yacc parser interface names (yyparse, yylex, yyerror, etc),
- as well as gratuitiously global symbol names, so we can have multiple
- yacc generated parsers in gdb. Note that these are only the variables
- produced by yacc. If other parser generators (bison, byacc, etc) produce
- additional global names that conflict at link time, then those parser
- generators need to be fixed instead of adding those names to this list. */
- #define yymaxdepth go_maxdepth
- #define yyparse go_parse_internal
- #define yylex go_lex
- #define yyerror go_error
- #define yylval go_lval
- #define yychar go_char
- #define yydebug go_debug
- #define yypact go_pact
- #define yyr1 go_r1
- #define yyr2 go_r2
- #define yydef go_def
- #define yychk go_chk
- #define yypgo go_pgo
- #define yyact go_act
- #define yyexca go_exca
- #define yyerrflag go_errflag
- #define yynerrs go_nerrs
- #define yyps go_ps
- #define yypv go_pv
- #define yys go_s
- #define yy_yys go_yys
- #define yystate go_state
- #define yytmp go_tmp
- #define yyv go_v
- #define yy_yyv go_yyv
- #define yyval go_val
- #define yylloc go_lloc
- #define yyreds go_reds /* With YYDEBUG defined */
- #define yytoks go_toks /* With YYDEBUG defined */
- #define yyname go_name /* With YYDEBUG defined */
- #define yyrule go_rule /* With YYDEBUG defined */
- #define yylhs go_yylhs
- #define yylen go_yylen
- #define yydefred go_yydefred
- #define yydgoto go_yydgoto
- #define yysindex go_yysindex
- #define yyrindex go_yyrindex
- #define yygindex go_yygindex
- #define yytable go_yytable
- #define yycheck go_yycheck
- #ifndef YYDEBUG
- #define YYDEBUG 1 /* Default to yydebug support */
- #endif
- #define YYFPRINTF parser_fprintf
- int yyparse (void);
- static int yylex (void);
- void yyerror (char *);
- %}
- /* Although the yacc "value" of an expression is not used,
- since the result is stored in the structure being created,
- other node types do have values. */
- %union
- {
- LONGEST lval;
- struct {
- LONGEST val;
- struct type *type;
- } typed_val_int;
- struct {
- DOUBLEST dval;
- struct type *type;
- } typed_val_float;
- struct stoken sval;
- struct symtoken ssym;
- struct type *tval;
- struct typed_stoken tsval;
- struct ttype tsym;
- int voidval;
- enum exp_opcode opcode;
- struct internalvar *ivar;
- struct stoken_vector svec;
- }
- %{
- /* YYSTYPE gets defined by %union. */
- static int parse_number (char *, int, int, YYSTYPE *);
- static int parse_go_float (struct gdbarch *gdbarch, const char *p, int len,
- DOUBLEST *d, struct type **t);
- %}
- %type <voidval> exp exp1 type_exp start variable lcurly
- %type <lval> rcurly
- %type <tval> type
- %token <typed_val_int> INT
- %token <typed_val_float> FLOAT
- /* Both NAME and TYPENAME tokens represent symbols in the input,
- and both convey their data as strings.
- But a TYPENAME is a string that happens to be defined as a type
- or builtin type name (such as int or char)
- and a NAME is any other symbol.
- Contexts where this distinction is not important can use the
- nonterminal "name", which matches either NAME or TYPENAME. */
- %token <tsval> RAW_STRING
- %token <tsval> STRING
- %token <tsval> CHAR
- %token <ssym> NAME
- %token <tsym> TYPENAME /* Not TYPE_NAME cus already taken. */
- %token <voidval> COMPLETE
- /*%type <sval> name*/
- %type <svec> string_exp
- %type <ssym> name_not_typename
- /* A NAME_OR_INT is a symbol which is not known in the symbol table,
- but which would parse as a valid number in the current input radix.
- E.g. "c" when input_radix==16. Depending on the parse, it will be
- turned into a name or into a number. */
- %token <ssym> NAME_OR_INT
- %token <lval> TRUE_KEYWORD FALSE_KEYWORD
- %token STRUCT_KEYWORD INTERFACE_KEYWORD TYPE_KEYWORD CHAN_KEYWORD
- %token SIZEOF_KEYWORD
- %token LEN_KEYWORD CAP_KEYWORD
- %token NEW_KEYWORD
- %token IOTA_KEYWORD NIL_KEYWORD
- %token CONST_KEYWORD
- %token DOTDOTDOT
- %token ENTRY
- %token ERROR
- /* Special type cases. */
- %token BYTE_KEYWORD /* An alias of uint8. */
- %token <sval> DOLLAR_VARIABLE
- %token <opcode> ASSIGN_MODIFY
- %left ','
- %left ABOVE_COMMA
- %right '=' ASSIGN_MODIFY
- %right '?'
- %left OROR
- %left ANDAND
- %left '|'
- %left '^'
- %left '&'
- %left ANDNOT
- %left EQUAL NOTEQUAL
- %left '<' '>' LEQ GEQ
- %left LSH RSH
- %left '@'
- %left '+' '-'
- %left '*' '/' '%'
- %right UNARY INCREMENT DECREMENT
- %right LEFT_ARROW '.' '[' '('
- %%
- start : exp1
- | type_exp
- ;
- type_exp: type
- { write_exp_elt_opcode(OP_TYPE);
- write_exp_elt_type($1);
- write_exp_elt_opcode(OP_TYPE); }
- ;
- /* Expressions, including the comma operator. */
- exp1 : exp
- | exp1 ',' exp
- { write_exp_elt_opcode (BINOP_COMMA); }
- ;
- /* Expressions, not including the comma operator. */
- exp : '*' exp %prec UNARY
- { write_exp_elt_opcode (UNOP_IND); }
- ;
- exp : '&' exp %prec UNARY
- { write_exp_elt_opcode (UNOP_ADDR); }
- ;
- exp : '-' exp %prec UNARY
- { write_exp_elt_opcode (UNOP_NEG); }
- ;
- exp : '+' exp %prec UNARY
- { write_exp_elt_opcode (UNOP_PLUS); }
- ;
- exp : '!' exp %prec UNARY
- { write_exp_elt_opcode (UNOP_LOGICAL_NOT); }
- ;
- exp : '^' exp %prec UNARY
- { write_exp_elt_opcode (UNOP_COMPLEMENT); }
- ;
- exp : exp INCREMENT %prec UNARY
- { write_exp_elt_opcode (UNOP_POSTINCREMENT); }
- ;
- exp : exp DECREMENT %prec UNARY
- { write_exp_elt_opcode (UNOP_POSTDECREMENT); }
- ;
- /* foo->bar is not in Go. May want as a gdb extension. Later. */
- exp : exp '.' name_not_typename
- { write_exp_elt_opcode (STRUCTOP_STRUCT);
- write_exp_string ($3.stoken);
- write_exp_elt_opcode (STRUCTOP_STRUCT); }
- ;
- exp : exp '.' name_not_typename COMPLETE
- { mark_struct_expression ();
- write_exp_elt_opcode (STRUCTOP_STRUCT);
- write_exp_string ($3.stoken);
- write_exp_elt_opcode (STRUCTOP_STRUCT); }
- ;
- exp : exp '.' COMPLETE
- { struct stoken s;
- mark_struct_expression ();
- write_exp_elt_opcode (STRUCTOP_STRUCT);
- s.ptr = "";
- s.length = 0;
- write_exp_string (s);
- write_exp_elt_opcode (STRUCTOP_STRUCT); }
- ;
- exp : exp '[' exp1 ']'
- { write_exp_elt_opcode (BINOP_SUBSCRIPT); }
- ;
- exp : exp '('
- /* This is to save the value of arglist_len
- being accumulated by an outer function call. */
- { start_arglist (); }
- arglist ')' %prec LEFT_ARROW
- { write_exp_elt_opcode (OP_FUNCALL);
- write_exp_elt_longcst ((LONGEST) end_arglist ());
- write_exp_elt_opcode (OP_FUNCALL); }
- ;
- lcurly : '{'
- { start_arglist (); }
- ;
- arglist :
- ;
- arglist : exp
- { arglist_len = 1; }
- ;
- arglist : arglist ',' exp %prec ABOVE_COMMA
- { arglist_len++; }
- ;
- rcurly : '}'
- { $$ = end_arglist () - 1; }
- ;
- exp : lcurly type rcurly exp %prec UNARY
- { write_exp_elt_opcode (UNOP_MEMVAL);
- write_exp_elt_type ($2);
- write_exp_elt_opcode (UNOP_MEMVAL); }
- ;
- exp : type '(' exp ')' %prec UNARY
- { write_exp_elt_opcode (UNOP_CAST);
- write_exp_elt_type ($1);
- write_exp_elt_opcode (UNOP_CAST); }
- ;
- exp : '(' exp1 ')'
- { }
- ;
- /* Binary operators in order of decreasing precedence. */
- exp : exp '@' exp
- { write_exp_elt_opcode (BINOP_REPEAT); }
- ;
- exp : exp '*' exp
- { write_exp_elt_opcode (BINOP_MUL); }
- ;
- exp : exp '/' exp
- { write_exp_elt_opcode (BINOP_DIV); }
- ;
- exp : exp '%' exp
- { write_exp_elt_opcode (BINOP_REM); }
- ;
- exp : exp '+' exp
- { write_exp_elt_opcode (BINOP_ADD); }
- ;
- exp : exp '-' exp
- { write_exp_elt_opcode (BINOP_SUB); }
- ;
- exp : exp LSH exp
- { write_exp_elt_opcode (BINOP_LSH); }
- ;
- exp : exp RSH exp
- { write_exp_elt_opcode (BINOP_RSH); }
- ;
- exp : exp EQUAL exp
- { write_exp_elt_opcode (BINOP_EQUAL); }
- ;
- exp : exp NOTEQUAL exp
- { write_exp_elt_opcode (BINOP_NOTEQUAL); }
- ;
- exp : exp LEQ exp
- { write_exp_elt_opcode (BINOP_LEQ); }
- ;
- exp : exp GEQ exp
- { write_exp_elt_opcode (BINOP_GEQ); }
- ;
- exp : exp '<' exp
- { write_exp_elt_opcode (BINOP_LESS); }
- ;
- exp : exp '>' exp
- { write_exp_elt_opcode (BINOP_GTR); }
- ;
- exp : exp '&' exp
- { write_exp_elt_opcode (BINOP_BITWISE_AND); }
- ;
- exp : exp '^' exp
- { write_exp_elt_opcode (BINOP_BITWISE_XOR); }
- ;
- exp : exp '|' exp
- { write_exp_elt_opcode (BINOP_BITWISE_IOR); }
- ;
- exp : exp ANDAND exp
- { write_exp_elt_opcode (BINOP_LOGICAL_AND); }
- ;
- exp : exp OROR exp
- { write_exp_elt_opcode (BINOP_LOGICAL_OR); }
- ;
- exp : exp '?' exp ':' exp %prec '?'
- { write_exp_elt_opcode (TERNOP_COND); }
- ;
- exp : exp '=' exp
- { write_exp_elt_opcode (BINOP_ASSIGN); }
- ;
- exp : exp ASSIGN_MODIFY exp
- { write_exp_elt_opcode (BINOP_ASSIGN_MODIFY);
- write_exp_elt_opcode ($2);
- write_exp_elt_opcode (BINOP_ASSIGN_MODIFY); }
- ;
- exp : INT
- { write_exp_elt_opcode (OP_LONG);
- write_exp_elt_type ($1.type);
- write_exp_elt_longcst ((LONGEST)($1.val));
- write_exp_elt_opcode (OP_LONG); }
- ;
- exp : CHAR
- {
- struct stoken_vector vec;
- vec.len = 1;
- vec.tokens = &$1;
- write_exp_string_vector ($1.type, &vec);
- }
- ;
- exp : NAME_OR_INT
- { YYSTYPE val;
- parse_number ($1.stoken.ptr, $1.stoken.length,
- 0, &val);
- write_exp_elt_opcode (OP_LONG);
- write_exp_elt_type (val.typed_val_int.type);
- write_exp_elt_longcst ((LONGEST)
- val.typed_val_int.val);
- write_exp_elt_opcode (OP_LONG);
- }
- ;
- exp : FLOAT
- { write_exp_elt_opcode (OP_DOUBLE);
- write_exp_elt_type ($1.type);
- write_exp_elt_dblcst ($1.dval);
- write_exp_elt_opcode (OP_DOUBLE); }
- ;
- exp : variable
- ;
- exp : DOLLAR_VARIABLE
- {
- write_dollar_variable ($1);
- }
- ;
- exp : SIZEOF_KEYWORD '(' type ')' %prec UNARY
- {
- /* TODO(dje): Go objects in structs. */
- write_exp_elt_opcode (OP_LONG);
- /* TODO(dje): What's the right type here? */
- write_exp_elt_type (parse_type->builtin_unsigned_int);
- CHECK_TYPEDEF ($3);
- write_exp_elt_longcst ((LONGEST) TYPE_LENGTH ($3));
- write_exp_elt_opcode (OP_LONG);
- }
- ;
- exp : SIZEOF_KEYWORD '(' exp ')' %prec UNARY
- {
- /* TODO(dje): Go objects in structs. */
- write_exp_elt_opcode (UNOP_SIZEOF);
- }
- string_exp:
- STRING
- {
- /* We copy the string here, and not in the
- lexer, to guarantee that we do not leak a
- string. */
- /* Note that we NUL-terminate here, but just
- for convenience. */
- struct typed_stoken *vec = XNEW (struct typed_stoken);
- $$.len = 1;
- $$.tokens = vec;
- vec->type = $1.type;
- vec->length = $1.length;
- vec->ptr = malloc ($1.length + 1);
- memcpy (vec->ptr, $1.ptr, $1.length + 1);
- }
- | string_exp '+' STRING
- {
- /* Note that we NUL-terminate here, but just
- for convenience. */
- char *p;
- ++$$.len;
- $$.tokens = realloc ($$.tokens,
- $$.len * sizeof (struct typed_stoken));
- p = malloc ($3.length + 1);
- memcpy (p, $3.ptr, $3.length + 1);
- $$.tokens[$$.len - 1].type = $3.type;
- $$.tokens[$$.len - 1].length = $3.length;
- $$.tokens[$$.len - 1].ptr = p;
- }
- ;
- exp : string_exp %prec ABOVE_COMMA
- {
- int i;
- write_exp_string_vector (0 /*always utf8*/, &$1);
- for (i = 0; i < $1.len; ++i)
- free ($1.tokens[i].ptr);
- free ($1.tokens);
- }
- ;
- exp : TRUE_KEYWORD
- { write_exp_elt_opcode (OP_BOOL);
- write_exp_elt_longcst ((LONGEST) $1);
- write_exp_elt_opcode (OP_BOOL); }
- ;
- exp : FALSE_KEYWORD
- { write_exp_elt_opcode (OP_BOOL);
- write_exp_elt_longcst ((LONGEST) $1);
- write_exp_elt_opcode (OP_BOOL); }
- ;
- variable: name_not_typename ENTRY
- { struct symbol *sym = $1.sym;
- if (sym == NULL
- || !SYMBOL_IS_ARGUMENT (sym)
- || !symbol_read_needs_frame (sym))
- error (_("@entry can be used only for function "
- "parameters, not for \"%s\""),
- copy_name ($1.stoken));
- write_exp_elt_opcode (OP_VAR_ENTRY_VALUE);
- write_exp_elt_sym (sym);
- write_exp_elt_opcode (OP_VAR_ENTRY_VALUE);
- }
- ;
- variable: name_not_typename
- { struct symbol *sym = $1.sym;
- if (sym)
- {
- if (symbol_read_needs_frame (sym))
- {
- if (innermost_block == 0
- || contained_in (block_found,
- innermost_block))
- innermost_block = block_found;
- }
- write_exp_elt_opcode (OP_VAR_VALUE);
- /* We want to use the selected frame, not
- another more inner frame which happens to
- be in the same block. */
- write_exp_elt_block (NULL);
- write_exp_elt_sym (sym);
- write_exp_elt_opcode (OP_VAR_VALUE);
- }
- else if ($1.is_a_field_of_this)
- {
- /* TODO(dje): Can we get here?
- E.g., via a mix of c++ and go? */
- gdb_assert_not_reached ("go with `this' field");
- }
- else
- {
- struct minimal_symbol *msymbol;
- char *arg = copy_name ($1.stoken);
- msymbol =
- lookup_minimal_symbol (arg, NULL, NULL);
- if (msymbol != NULL)
- write_exp_msymbol (msymbol);
- else if (!have_full_symbols ()
- && !have_partial_symbols ())
- error (_("No symbol table is loaded. "
- "Use the \"file\" command."));
- else
- error (_("No symbol \"%s\" in current context."),
- copy_name ($1.stoken));
- }
- }
- ;
- /* TODO
- method_exp: PACKAGENAME '.' name '.' name
- {
- }
- ;
- */
- type /* Implements (approximately): [*] type-specifier */
- : '*' type
- { $$ = lookup_pointer_type ($2); }
- | TYPENAME
- { $$ = $1.type; }
- /*
- | STRUCT_KEYWORD name
- { $$ = lookup_struct (copy_name ($2),
- expression_context_block); }
- */
- | BYTE_KEYWORD
- { $$ = builtin_go_type (parse_gdbarch)
- ->builtin_uint8; }
- ;
- /* TODO
- name : NAME { $$ = $1.stoken; }
- | TYPENAME { $$ = $1.stoken; }
- | NAME_OR_INT { $$ = $1.stoken; }
- ;
- */
- name_not_typename
- : NAME
- /* These would be useful if name_not_typename was useful, but it is just
- a fake for "variable", so these cause reduce/reduce conflicts because
- the parser can't tell whether NAME_OR_INT is a name_not_typename (=variable,
- =exp) or just an exp. If name_not_typename was ever used in an lvalue
- context where only a name could occur, this might be useful.
- | NAME_OR_INT
- */
- ;
- %%
- /* Wrapper on parse_c_float to get the type right for Go. */
- static int
- parse_go_float (struct gdbarch *gdbarch, const char *p, int len,
- DOUBLEST *d, struct type **t)
- {
- int result = parse_c_float (gdbarch, p, len, d, t);
- const struct builtin_type *builtin_types = builtin_type (gdbarch);
- const struct builtin_go_type *builtin_go_types = builtin_go_type (gdbarch);
- if (*t == builtin_types->builtin_float)
- *t = builtin_go_types->builtin_float32;
- else if (*t == builtin_types->builtin_double)
- *t = builtin_go_types->builtin_float64;
- return result;
- }
- /* Take care of parsing a number (anything that starts with a digit).
- Set yylval and return the token type; update lexptr.
- LEN is the number of characters in it. */
- /* FIXME: Needs some error checking for the float case. */
- /* FIXME(dje): IWBN to use c-exp.y's parse_number if we could.
- That will require moving the guts into a function that we both call
- as our YYSTYPE is different than c-exp.y's */
- static int
- parse_number (char *p, int len, int parsed_float, YYSTYPE *putithere)
- {
- /* FIXME: Shouldn't these be unsigned? We don't deal with negative values
- here, and we do kind of silly things like cast to unsigned. */
- LONGEST n = 0;
- LONGEST prevn = 0;
- ULONGEST un;
- int i = 0;
- int c;
- int base = input_radix;
- int unsigned_p = 0;
- /* Number of "L" suffixes encountered. */
- int long_p = 0;
- /* We have found a "L" or "U" suffix. */
- int found_suffix = 0;
- ULONGEST high_bit;
- struct type *signed_type;
- struct type *unsigned_type;
- if (parsed_float)
- {
- if (! parse_go_float (parse_gdbarch, p, len,
- &putithere->typed_val_float.dval,
- &putithere->typed_val_float.type))
- return ERROR;
- return FLOAT;
- }
- /* Handle base-switching prefixes 0x, 0t, 0d, 0. */
- if (p[0] == '0')
- switch (p[1])
- {
- case 'x':
- case 'X':
- if (len >= 3)
- {
- p += 2;
- base = 16;
- len -= 2;
- }
- break;
- case 'b':
- case 'B':
- if (len >= 3)
- {
- p += 2;
- base = 2;
- len -= 2;
- }
- break;
- case 't':
- case 'T':
- case 'd':
- case 'D':
- if (len >= 3)
- {
- p += 2;
- base = 10;
- len -= 2;
- }
- break;
- default:
- base = 8;
- break;
- }
- while (len-- > 0)
- {
- c = *p++;
- if (c >= 'A' && c <= 'Z')
- c += 'a' - 'A';
- if (c != 'l' && c != 'u')
- n *= base;
- if (c >= '0' && c <= '9')
- {
- if (found_suffix)
- return ERROR;
- n += i = c - '0';
- }
- else
- {
- if (base > 10 && c >= 'a' && c <= 'f')
- {
- if (found_suffix)
- return ERROR;
- n += i = c - 'a' + 10;
- }
- else if (c == 'l')
- {
- ++long_p;
- found_suffix = 1;
- }
- else if (c == 'u')
- {
- unsigned_p = 1;
- found_suffix = 1;
- }
- else
- return ERROR; /* Char not a digit */
- }
- if (i >= base)
- return ERROR; /* Invalid digit in this base. */
- /* Portably test for overflow (only works for nonzero values, so make
- a second check for zero). FIXME: Can't we just make n and prevn
- unsigned and avoid this? */
- if (c != 'l' && c != 'u' && (prevn >= n) && n != 0)
- unsigned_p = 1; /* Try something unsigned. */
- /* Portably test for unsigned overflow.
- FIXME: This check is wrong; for example it doesn't find overflow
- on 0x123456789 when LONGEST is 32 bits. */
- if (c != 'l' && c != 'u' && n != 0)
- {
- if ((unsigned_p && (ULONGEST) prevn >= (ULONGEST) n))
- error (_("Numeric constant too large."));
- }
- prevn = n;
- }
- /* An integer constant is an int, a long, or a long long. An L
- suffix forces it to be long; an LL suffix forces it to be long
- long. If not forced to a larger size, it gets the first type of
- the above that it fits in. To figure out whether it fits, we
- shift it right and see whether anything remains. Note that we
- can't shift sizeof (LONGEST) * HOST_CHAR_BIT bits or more in one
- operation, because many compilers will warn about such a shift
- (which always produces a zero result). Sometimes gdbarch_int_bit
- or gdbarch_long_bit will be that big, sometimes not. To deal with
- the case where it is we just always shift the value more than
- once, with fewer bits each time. */
- un = (ULONGEST)n >> 2;
- if (long_p == 0
- && (un >> (gdbarch_int_bit (parse_gdbarch) - 2)) == 0)
- {
- high_bit = ((ULONGEST)1) << (gdbarch_int_bit (parse_gdbarch) - 1);
- /* A large decimal (not hex or octal) constant (between INT_MAX
- and UINT_MAX) is a long or unsigned long, according to ANSI,
- never an unsigned int, but this code treats it as unsigned
- int. This probably should be fixed. GCC gives a warning on
- such constants. */
- unsigned_type = parse_type->builtin_unsigned_int;
- signed_type = parse_type->builtin_int;
- }
- else if (long_p <= 1
- && (un >> (gdbarch_long_bit (parse_gdbarch) - 2)) == 0)
- {
- high_bit = ((ULONGEST)1) << (gdbarch_long_bit (parse_gdbarch) - 1);
- unsigned_type = parse_type->builtin_unsigned_long;
- signed_type = parse_type->builtin_long;
- }
- else
- {
- int shift;
- if (sizeof (ULONGEST) * HOST_CHAR_BIT
- < gdbarch_long_long_bit (parse_gdbarch))
- /* A long long does not fit in a LONGEST. */
- shift = (sizeof (ULONGEST) * HOST_CHAR_BIT - 1);
- else
- shift = (gdbarch_long_long_bit (parse_gdbarch) - 1);
- high_bit = (ULONGEST) 1 << shift;
- unsigned_type = parse_type->builtin_unsigned_long_long;
- signed_type = parse_type->builtin_long_long;
- }
- putithere->typed_val_int.val = n;
- /* If the high bit of the worked out type is set then this number
- has to be unsigned. */
- if (unsigned_p || (n & high_bit))
- {
- putithere->typed_val_int.type = unsigned_type;
- }
- else
- {
- putithere->typed_val_int.type = signed_type;
- }
- return INT;
- }
- /* Temporary obstack used for holding strings. */
- static struct obstack tempbuf;
- static int tempbuf_init;
- /* Parse a string or character literal from TOKPTR. The string or
- character may be wide or unicode. *OUTPTR is set to just after the
- end of the literal in the input string. The resulting token is
- stored in VALUE. This returns a token value, either STRING or
- CHAR, depending on what was parsed. *HOST_CHARS is set to the
- number of host characters in the literal. */
- static int
- parse_string_or_char (char *tokptr, char **outptr, struct typed_stoken *value,
- int *host_chars)
- {
- int quote;
- /* Build the gdb internal form of the input string in tempbuf. Note
- that the buffer is null byte terminated *only* for the
- convenience of debugging gdb itself and printing the buffer
- contents when the buffer contains no embedded nulls. Gdb does
- not depend upon the buffer being null byte terminated, it uses
- the length string instead. This allows gdb to handle C strings
- (as well as strings in other languages) with embedded null
- bytes */
- if (!tempbuf_init)
- tempbuf_init = 1;
- else
- obstack_free (&tempbuf, NULL);
- obstack_init (&tempbuf);
- /* Skip the quote. */
- quote = *tokptr;
- ++tokptr;
- *host_chars = 0;
- while (*tokptr)
- {
- char c = *tokptr;
- if (c == '\\')
- {
- ++tokptr;
- *host_chars += c_parse_escape (&tokptr, &tempbuf);
- }
- else if (c == quote)
- break;
- else
- {
- obstack_1grow (&tempbuf, c);
- ++tokptr;
- /* FIXME: this does the wrong thing with multi-byte host
- characters. We could use mbrlen here, but that would
- make "set host-charset" a bit less useful. */
- ++*host_chars;
- }
- }
- if (*tokptr != quote)
- {
- if (quote == '"')
- error (_("Unterminated string in expression."));
- else
- error (_("Unmatched single quote."));
- }
- ++tokptr;
- value->type = C_STRING | (quote == '\'' ? C_CHAR : 0); /*FIXME*/
- value->ptr = obstack_base (&tempbuf);
- value->length = obstack_object_size (&tempbuf);
- *outptr = tokptr;
- return quote == '\'' ? CHAR : STRING;
- }
- struct token
- {
- char *operator;
- int token;
- enum exp_opcode opcode;
- };
- static const struct token tokentab3[] =
- {
- {">>=", ASSIGN_MODIFY, BINOP_RSH},
- {"<<=", ASSIGN_MODIFY, BINOP_LSH},
- /*{"&^=", ASSIGN_MODIFY, BINOP_BITWISE_ANDNOT}, TODO */
- {"...", DOTDOTDOT, OP_NULL},
- };
- static const struct token tokentab2[] =
- {
- {"+=", ASSIGN_MODIFY, BINOP_ADD},
- {"-=", ASSIGN_MODIFY, BINOP_SUB},
- {"*=", ASSIGN_MODIFY, BINOP_MUL},
- {"/=", ASSIGN_MODIFY, BINOP_DIV},
- {"%=", ASSIGN_MODIFY, BINOP_REM},
- {"|=", ASSIGN_MODIFY, BINOP_BITWISE_IOR},
- {"&=", ASSIGN_MODIFY, BINOP_BITWISE_AND},
- {"^=", ASSIGN_MODIFY, BINOP_BITWISE_XOR},
- {"++", INCREMENT, BINOP_END},
- {"--", DECREMENT, BINOP_END},
- /*{"->", RIGHT_ARROW, BINOP_END}, Doesn't exist in Go. */
- {"<-", LEFT_ARROW, BINOP_END},
- {"&&", ANDAND, BINOP_END},
- {"||", OROR, BINOP_END},
- {"<<", LSH, BINOP_END},
- {">>", RSH, BINOP_END},
- {"==", EQUAL, BINOP_END},
- {"!=", NOTEQUAL, BINOP_END},
- {"<=", LEQ, BINOP_END},
- {">=", GEQ, BINOP_END},
- /*{"&^", ANDNOT, BINOP_END}, TODO */
- };
- /* Identifier-like tokens. */
- static const struct token ident_tokens[] =
- {
- {"true", TRUE_KEYWORD, OP_NULL},
- {"false", FALSE_KEYWORD, OP_NULL},
- {"nil", NIL_KEYWORD, OP_NULL},
- {"const", CONST_KEYWORD, OP_NULL},
- {"struct", STRUCT_KEYWORD, OP_NULL},
- {"type", TYPE_KEYWORD, OP_NULL},
- {"interface", INTERFACE_KEYWORD, OP_NULL},
- {"chan", CHAN_KEYWORD, OP_NULL},
- {"byte", BYTE_KEYWORD, OP_NULL}, /* An alias of uint8. */
- {"len", LEN_KEYWORD, OP_NULL},
- {"cap", CAP_KEYWORD, OP_NULL},
- {"new", NEW_KEYWORD, OP_NULL},
- {"iota", IOTA_KEYWORD, OP_NULL},
- };
- /* This is set if a NAME token appeared at the very end of the input
- string, with no whitespace separating the name from the EOF. This
- is used only when parsing to do field name completion. */
- static int saw_name_at_eof;
- /* This is set if the previously-returned token was a structure
- operator -- either '.' or ARROW. This is used only when parsing to
- do field name completion. */
- static int last_was_structop;
- /* Read one token, getting characters through lexptr. */
- static int
- lex_one_token (void)
- {
- int c;
- int namelen;
- unsigned int i;
- char *tokstart;
- int saw_structop = last_was_structop;
- char *copy;
- last_was_structop = 0;
- retry:
- prev_lexptr = lexptr;
- tokstart = lexptr;
- /* See if it is a special token of length 3. */
- for (i = 0; i < sizeof (tokentab3) / sizeof (tokentab3[0]); i++)
- if (strncmp (tokstart, tokentab3[i].operator, 3) == 0)
- {
- lexptr += 3;
- yylval.opcode = tokentab3[i].opcode;
- return tokentab3[i].token;
- }
- /* See if it is a special token of length 2. */
- for (i = 0; i < sizeof (tokentab2) / sizeof (tokentab2[0]); i++)
- if (strncmp (tokstart, tokentab2[i].operator, 2) == 0)
- {
- lexptr += 2;
- yylval.opcode = tokentab2[i].opcode;
- /* NOTE: -> doesn't exist in Go, so we don't need to watch for
- setting last_was_structop here. */
- return tokentab2[i].token;
- }
- switch (c = *tokstart)
- {
- case 0:
- if (saw_name_at_eof)
- {
- saw_name_at_eof = 0;
- return COMPLETE;
- }
- else if (saw_structop)
- return COMPLETE;
- else
- return 0;
- case ' ':
- case '\t':
- case '\n':
- lexptr++;
- goto retry;
- case '[':
- case '(':
- paren_depth++;
- lexptr++;
- return c;
- case ']':
- case ')':
- if (paren_depth == 0)
- return 0;
- paren_depth--;
- lexptr++;
- return c;
- case ',':
- if (comma_terminates
- && paren_depth == 0)
- return 0;
- lexptr++;
- return c;
- case '.':
- /* Might be a floating point number. */
- if (lexptr[1] < '0' || lexptr[1] > '9')
- {
- if (in_parse_field)
- last_was_structop = 1;
- goto symbol; /* Nope, must be a symbol. */
- }
- /* FALL THRU into number case. */
- case '0':
- case '1':
- case '2':
- case '3':
- case '4':
- case '5':
- case '6':
- case '7':
- case '8':
- case '9':
- {
- /* It's a number. */
- int got_dot = 0, got_e = 0, toktype;
- char *p = tokstart;
- int hex = input_radix > 10;
- if (c == '0' && (p[1] == 'x' || p[1] == 'X'))
- {
- p += 2;
- hex = 1;
- }
- for (;; ++p)
- {
- /* This test includes !hex because 'e' is a valid hex digit
- and thus does not indicate a floating point number when
- the radix is hex. */
- if (!hex && !got_e && (*p == 'e' || *p == 'E'))
- got_dot = got_e = 1;
- /* This test does not include !hex, because a '.' always indicates
- a decimal floating point number regardless of the radix. */
- else if (!got_dot && *p == '.')
- got_dot = 1;
- else if (got_e && (p[-1] == 'e' || p[-1] == 'E')
- && (*p == '-' || *p == '+'))
- /* This is the sign of the exponent, not the end of the
- number. */
- continue;
- /* We will take any letters or digits. parse_number will
- complain if past the radix, or if L or U are not final. */
- else if ((*p < '0' || *p > '9')
- && ((*p < 'a' || *p > 'z')
- && (*p < 'A' || *p > 'Z')))
- break;
- }
- toktype = parse_number (tokstart, p - tokstart, got_dot|got_e, &yylval);
- if (toktype == ERROR)
- {
- char *err_copy = (char *) alloca (p - tokstart + 1);
- memcpy (err_copy, tokstart, p - tokstart);
- err_copy[p - tokstart] = 0;
- error (_("Invalid number \"%s\"."), err_copy);
- }
- lexptr = p;
- return toktype;
- }
- case '@':
- {
- char *p = &tokstart[1];
- size_t len = strlen ("entry");
- while (isspace (*p))
- p++;
- if (strncmp (p, "entry", len) == 0 && !isalnum (p[len])
- && p[len] != '_')
- {
- lexptr = &p[len];
- return ENTRY;
- }
- }
- /* FALLTHRU */
- case '+':
- case '-':
- case '*':
- case '/':
- case '%':
- case '|':
- case '&':
- case '^':
- case '~':
- case '!':
- case '<':
- case '>':
- case '?':
- case ':':
- case '=':
- case '{':
- case '}':
- symbol:
- lexptr++;
- return c;
- case '\'':
- case '"':
- case '`':
- {
- int host_len;
- int result = parse_string_or_char (tokstart, &lexptr, &yylval.tsval,
- &host_len);
- if (result == CHAR)
- {
- if (host_len == 0)
- error (_("Empty character constant."));
- else if (host_len > 2 && c == '\'')
- {
- ++tokstart;
- namelen = lexptr - tokstart - 1;
- goto tryname;
- }
- else if (host_len > 1)
- error (_("Invalid character constant."));
- }
- return result;
- }
- }
- if (!(c == '_' || c == '$'
- || (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z')))
- /* We must have come across a bad character (e.g. ';'). */
- error (_("Invalid character '%c' in expression."), c);
- /* It's a name. See how long it is. */
- namelen = 0;
- for (c = tokstart[namelen];
- (c == '_' || c == '$' || (c >= '0' && c <= '9')
- || (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z'));)
- {
- c = tokstart[++namelen];
- }
- /* The token "if" terminates the expression and is NOT removed from
- the input stream. It doesn't count if it appears in the
- expansion of a macro. */
- if (namelen == 2
- && tokstart[0] == 'i'
- && tokstart[1] == 'f')
- {
- return 0;
- }
- /* For the same reason (breakpoint conditions), "thread N"
- terminates the expression. "thread" could be an identifier, but
- an identifier is never followed by a number without intervening
- punctuation.
- Handle abbreviations of these, similarly to
- breakpoint.c:find_condition_and_thread.
- TODO: Watch for "goroutine" here? */
- if (namelen >= 1
- && strncmp (tokstart, "thread", namelen) == 0
- && (tokstart[namelen] == ' ' || tokstart[namelen] == '\t'))
- {
- char *p = tokstart + namelen + 1;
- while (*p == ' ' || *p == '\t')
- p++;
- if (*p >= '0' && *p <= '9')
- return 0;
- }
- lexptr += namelen;
- tryname:
- yylval.sval.ptr = tokstart;
- yylval.sval.length = namelen;
- /* Catch specific keywords. */
- copy = copy_name (yylval.sval);
- for (i = 0; i < sizeof (ident_tokens) / sizeof (ident_tokens[0]); i++)
- if (strcmp (copy, ident_tokens[i].operator) == 0)
- {
- /* It is ok to always set this, even though we don't always
- strictly need to. */
- yylval.opcode = ident_tokens[i].opcode;
- return ident_tokens[i].token;
- }
- if (*tokstart == '$')
- return DOLLAR_VARIABLE;
- if (in_parse_field && *lexptr == '\0')
- saw_name_at_eof = 1;
- return NAME;
- }
- /* An object of this type is pushed on a FIFO by the "outer" lexer. */
- typedef struct
- {
- int token;
- YYSTYPE value;
- } token_and_value;
- DEF_VEC_O (token_and_value);
- /* A FIFO of tokens that have been read but not yet returned to the
- parser. */
- static VEC (token_and_value) *token_fifo;
- /* Non-zero if the lexer should return tokens from the FIFO. */
- static int popping;
- /* Temporary storage for yylex; this holds symbol names as they are
- built up. */
- static struct obstack name_obstack;
- /* Build "package.name" in name_obstack.
- For convenience of the caller, the name is NUL-terminated,
- but the NUL is not included in the recorded length. */
- static struct stoken
- build_packaged_name (const char *package, int package_len,
- const char *name, int name_len)
- {
- struct stoken result;
- obstack_free (&name_obstack, obstack_base (&name_obstack));
- obstack_grow (&name_obstack, package, package_len);
- obstack_grow_str (&name_obstack, ".");
- obstack_grow (&name_obstack, name, name_len);
- obstack_grow (&name_obstack, "", 1);
- result.ptr = obstack_base (&name_obstack);
- result.length = obstack_object_size (&name_obstack) - 1;
- return result;
- }
- /* Return non-zero if NAME is a package name.
- BLOCK is the scope in which to interpret NAME; this can be NULL
- to mean the global scope. */
- static int
- package_name_p (const char *name, struct block *block)
- {
- struct symbol *sym;
- int is_a_field_of_this;
- sym = lookup_symbol (name, block, STRUCT_DOMAIN, &is_a_field_of_this);
- if (sym
- && SYMBOL_CLASS (sym) == LOC_TYPEDEF
- && TYPE_CODE (SYMBOL_TYPE (sym)) == TYPE_CODE_MODULE)
- return 1;
- return 0;
- }
- /* Classify a (potential) function in the "unsafe" package.
- We fold these into "keywords" to keep things simple, at least until
- something more complex is warranted. */
- static int
- classify_unsafe_function (struct stoken function_name)
- {
- char *copy = copy_name (function_name);
- if (strcmp (copy, "Sizeof") == 0)
- {
- yylval.sval = function_name;
- return SIZEOF_KEYWORD;
- }
- error (_("Unknown function in `unsafe' package: %s"), copy);
- }
- /* Classify token(s) "name1.name2" where name1 is known to be a package.
- The contents of the token are in `yylval'.
- Updates yylval and returns the new token type.
- The result is one of NAME, NAME_OR_INT, or TYPENAME. */
- static int
- classify_packaged_name (struct block *block)
- {
- char *copy;
- struct symbol *sym;
- int is_a_field_of_this = 0;
- copy = copy_name (yylval.sval);
- sym = lookup_symbol (copy, block, VAR_DOMAIN, &is_a_field_of_this);
- if (sym)
- {
- yylval.ssym.sym = sym;
- yylval.ssym.is_a_field_of_this = is_a_field_of_this;
- }
- return NAME;
- }
- /* Classify a NAME token.
- The contents of the token are in `yylval'.
- Updates yylval and returns the new token type.
- BLOCK is the block in which lookups start; this can be NULL
- to mean the global scope.
- The result is one of NAME, NAME_OR_INT, or TYPENAME. */
- static int
- classify_name (struct block *block)
- {
- struct type *type;
- struct symbol *sym;
- char *copy;
- int is_a_field_of_this = 0;
- copy = copy_name (yylval.sval);
- /* Try primitive types first so they win over bad/weird debug info. */
- type = language_lookup_primitive_type_by_name (parse_language,
- parse_gdbarch, copy);
- if (type != NULL)
- {
- /* NOTE: We take advantage of the fact that yylval coming in was a
- NAME, and that struct ttype is a compatible extension of struct
- stoken, so yylval.tsym.stoken is already filled in. */
- yylval.tsym.type = type;
- return TYPENAME;
- }
- /* TODO: What about other types? */
- sym = lookup_symbol (copy, block, VAR_DOMAIN, &is_a_field_of_this);
- if (sym)
- {
- yylval.ssym.sym = sym;
- yylval.ssym.is_a_field_of_this = is_a_field_of_this;
- return NAME;
- }
- /* If we didn't find a symbol, look again in the current package.
- This is to, e.g., make "p global_var" work without having to specify
- the package name. We intentionally only looks for objects in the
- current package. */
- {
- char *current_package_name = go_block_package_name (block);
- if (current_package_name != NULL)
- {
- struct stoken sval =
- build_packaged_name (current_package_name,
- strlen (current_package_name),
- copy, strlen (copy));
- xfree (current_package_name);
- sym = lookup_symbol (sval.ptr, block, VAR_DOMAIN,
- &is_a_field_of_this);
- if (sym)
- {
- yylval.ssym.stoken = sval;
- yylval.ssym.sym = sym;
- yylval.ssym.is_a_field_of_this = is_a_field_of_this;
- return NAME;
- }
- }
- }
- /* Input names that aren't symbols but ARE valid hex numbers, when
- the input radix permits them, can be names or numbers depending
- on the parse. Note we support radixes > 16 here. */
- if ((copy[0] >= 'a' && copy[0] < 'a' + input_radix - 10)
- || (copy[0] >= 'A' && copy[0] < 'A' + input_radix - 10))
- {
- YYSTYPE newlval; /* Its value is ignored. */
- int hextype = parse_number (copy, yylval.sval.length, 0, &newlval);
- if (hextype == INT)
- {
- yylval.ssym.sym = NULL;
- yylval.ssym.is_a_field_of_this = 0;
- return NAME_OR_INT;
- }
- }
- yylval.ssym.sym = NULL;
- yylval.ssym.is_a_field_of_this = 0;
- return NAME;
- }
- /* This is taken from c-exp.y mostly to get something working.
- The basic structure has been kept because we may yet need some of it. */
- static int
- yylex (void)
- {
- token_and_value current, next;
- if (popping && !VEC_empty (token_and_value, token_fifo))
- {
- token_and_value tv = *VEC_index (token_and_value, token_fifo, 0);
- VEC_ordered_remove (token_and_value, token_fifo, 0);
- yylval = tv.value;
- /* There's no need to fall through to handle package.name
- as that can never happen here. In theory. */
- return tv.token;
- }
- popping = 0;
- current.token = lex_one_token ();
- /* TODO: Need a way to force specifying name1 as a package.
- .name1.name2 ? */
- if (current.token != NAME)
- return current.token;
- /* See if we have "name1 . name2". */
- current.value = yylval;
- next.token = lex_one_token ();
- next.value = yylval;
- if (next.token == '.')
- {
- token_and_value name2;
- name2.token = lex_one_token ();
- name2.value = yylval;
- if (name2.token == NAME)
- {
- /* Ok, we have "name1 . name2". */
- char *copy;
- copy = copy_name (current.value.sval);
- if (strcmp (copy, "unsafe") == 0)
- {
- popping = 1;
- return classify_unsafe_function (name2.value.sval);
- }
- if (package_name_p (copy, expression_context_block))
- {
- popping = 1;
- yylval.sval = build_packaged_name (current.value.sval.ptr,
- current.value.sval.length,
- name2.value.sval.ptr,
- name2.value.sval.length);
- return classify_packaged_name (expression_context_block);
- }
- }
- VEC_safe_push (token_and_value, token_fifo, &next);
- VEC_safe_push (token_and_value, token_fifo, &name2);
- }
- else
- {
- VEC_safe_push (token_and_value, token_fifo, &next);
- }
- /* If we arrive here we don't have a package-qualified name. */
- popping = 1;
- yylval = current.value;
- return classify_name (expression_context_block);
- }
- int
- go_parse (void)
- {
- int result;
- struct cleanup *back_to = make_cleanup (null_cleanup, NULL);
- make_cleanup_restore_integer (&yydebug);
- yydebug = parser_debug;
- /* Initialize some state used by the lexer. */
- last_was_structop = 0;
- saw_name_at_eof = 0;
- VEC_free (token_and_value, token_fifo);
- popping = 0;
- obstack_init (&name_obstack);
- make_cleanup_obstack_free (&name_obstack);
- result = yyparse ();
- do_cleanups (back_to);
- return result;
- }
- void
- yyerror (char *msg)
- {
- if (prev_lexptr)
- lexptr = prev_lexptr;
- error (_("A %s in expression, near `%s'."), (msg ? msg : "error"), lexptr);
- }