mirror/binutils-gdb
2
0
Fork 0
mirror of https://sourceware.org/git/binutils-gdb.git synced 2024-12-21 04:42:53 +08:00
Code Issues Packages Projects Releases Wiki Activity
c2252c0dd8
binutils-gdb/gdb/parser-defs.h
Ulrich Weigand edd079d9f6 Target FP: Use target format throughout expression parsing 
When parsing floating-point literals, the language parsers currently
use parse_float or some equivalent routine to parse the input string
into a DOUBLEST, which is then stored within a OP_DOUBLE expression
node.  When evaluating the expression, the OP_DOUBLE is finally
converted into a value in target format.

On the other hand, *decimal* floating-point literals are parsed
directly into target format and stored that way in a OP_DECFLOAT
expression node.  In order to eliminate the DOUBLEST, this patch
therefore unifies the handling of binary and decimal floating-
point literals and stores them both in target format within a
new OP_FLOAT expression node, replacing both OP_DOUBLE and
OP_DECFLOAT.

In order to store literals in target format, the parse_float
routine needs to know the type of the literal.  All parsers
therefore need to be changed to determine the appropriate type
(e.g. by detecting suffixes) *before* calling parse_float,
instead of after it as today.  However, this change is mostly
straightforward -- again, this is already done for decimal FP
today.

The core of the literal parsing is moved into a new routine
floatformat_from_string, mirroring floatformat_to_string.
The parse_float routine now calls either floatformat_from_string
or decimal_from_sting, allowing it to handle any type of FP
literal.

All language parsers need to be updated.  Some notes on
specific changes to the various languages:

- C: Decimal FP is now handled in parse_float, and no longer
  needs to be handled specially.

- D: Straightforward.

- Fortran: Still used a hard-coded "atof", also replaced by
  parse_float now.  Continues to always use builtin_real_s8
  as the type of literal, even though this is probably wrong.

- Go: This used to handle "f" and "l" suffixes, even though
  the Go language actually doesn't support those.  I kept this
  support for now -- maybe revisit later.  Note the the GDB
  test suite for some reason actually *verifies* that GDB supports
  those unsupported suffixes ...

- Pascal: Likewise -- this handles suffixes that are not
  supported in the language standard.

- Modula-2: Like Fortran, used to use "atof".

- Rust: Mostly straightforward, except for a unit-testing hitch.
  The code use to set a special "unit_testing" flag which would
  cause "rust_type" to always return NULL.  This makes it not
  possible to encode a literal into target format (which type?).
  The reason for this flag appears to have been that during
  unit testing, there is no "rust_parser" context set up, which
  means no "gdbarch" is available to use its types.  To fix this,
  I removed the unit_testing flag, and instead simply just set up
  a dummy rust_parser context during unit testing.

- Ada: This used to check sizeof (DOUBLEST) to determine which
  type to use for floating-point literal.  This seems questionable
  to begin with (since DOUBLEST is quite unrelated to target formats),
  and in any case we need to get rid of DOUBLEST.  I'm now simply
  always using the largest type (builtin_long_double).

gdb/ChangeLog:
2017-10-25  Ulrich Weigand  <uweigand@de.ibm.com>

	* doublest.c (floatformat_from_string): New function.
	* doublest.h (floatformat_from_string): Add prototype.

	* std-operator.def (OP_DOUBLE, OP_DECFLOAT): Remove, replace by ...
	(OP_FLOAT): ... this.
	* expression.h: Do not include "doublest.h".
	(union exp_element): Replace doubleconst and decfloatconst by
	new element floatconst.
	* ada-lang.c (resolve_subexp): Handle OP_FLOAT instead of OP_DOUBLE.
	(ada_evaluate_subexp): Likewise.
	* eval.c (evaluate_subexp_standard): Handle OP_FLOAT instead of
	OP_DOUBLE and OP_DECFLOAT.
	* expprint.c (print_subexp_standard): Likewise.
	(dump_subexp_body_standard): Likewise.
	* breakpoint.c (watchpoint_exp_is_const): Likewise.

	* parse.c: Include "dfp.h".
	(write_exp_elt_dblcst, write_exp_elt_decfloatcst): Remove.
	(write_exp_elt_floatcst): New function.
	(operator_length_standard): Handle OP_FLOAT instead of OP_DOUBLE
	and OP_DECFLOAT.
	(operator_check_standard): Likewise.
	(parse_float): Do not accept suffix.  Take type as input.  Return bool.
	Return target format buffer instead of host DOUBLEST.
	Use floatformat_from_string and decimal_from_string to parse
	either binary or decimal floating-point types.
	(parse_c_float): Remove.
	* parser-defs.h: Do not include "doublest.h".
	(write_exp_elt_dblcst, write_exp_elt_decfloatcst): Remove.
	(write_exp_elt_floatcst): Add prototype.
	(parse_float): Update prototype.
	(parse_c_float): Remove.

	* c-exp.y: Do not include "dfp.h".
	(typed_val_float): Use byte buffer instead of DOUBLEST.
	(typed_val_decfloat): Remove.
	(DECFLOAT): Remove.
	(FLOAT): Use OP_FLOAT and write_exp_elt_floatcst.
	(parse_number): Update to new parse_float interface.
	Parse suffixes and determine type before calling parse_float.
	Handle decimal and binary FP types the same way.

	* d-exp.y (typed_val_float): Use byte buffer instead of DOUBLEST.
	(FLOAT_LITERAL): Use OP_FLOAT and write_exp_elt_floatcst.
	(parse_number): Update to new parse_float interface.
	Parse suffixes and determine type before calling parse_float.

	* f-exp.y: Replace dval by typed_val_float.
	(FLOAT): Use OP_FLOAT and write_exp_elt_floatcst.
	(parse_number): Use parse_float instead of atof.

	* go-exp.y (typed_val_float): Use byte buffer instead of DOUBLEST.
	(parse_go_float): Remove.
	(FLOAT): Use OP_FLOAT and write_exp_elt_floatcst.
	(parse_number): Call parse_float instead of parse_go_float.
	Parse suffixes and determine type before calling parse_float.

	* p-exp.y (typed_val_float): Use byte buffer instead of DOUBLEST.
	(FLOAT): Use OP_FLOAT and write_exp_elt_floatcst.
	(parse_number): Update to new parse_float interface.
	Parse suffixes and determine type before calling parse_float.

	* m2-exp.y: Replace dval by byte buffer val.
	(FLOAT): Use OP_FLOAT and write_exp_elt_floatcst.
	(parse_number): Call parse_float instead of atof.

	* rust-exp.y (typed_val_float): Use byte buffer instead of DOUBLEST.
	(lex_number): Call parse_float instead of strtod.
	(ast_dliteral): Use OP_FLOAT instead of OP_DOUBLE.
	(convert_ast_to_expression): Handle OP_FLOAT instead of OP_DOUBLE.
	Use write_exp_elt_floatcst.
	(unit_testing): Remove static variable.
	(rust_type): Do not check unit_testing.
	(rust_lex_tests): Do not set uint_testing.  Set up dummy rust_parser.

	* ada-exp.y (type_float, type_double): Remove.
	(typed_val_float): Use byte buffer instead of DOUBLEST.
	(FLOAT): Use OP_FLOAT and write_exp_elt_floatcst.
	* ada-lex.l (processReal): Use parse_float instead of sscanf.
2017-10-25 15:32:23 +02:00

395 lines
12 KiB
C
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

/* Parser definitions for GDB.
Copyright (C) 1986-2017 Free Software Foundation, Inc.
Modified from expread.y by the Department of Computer Science at the
State University of New York at Buffalo.
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/>. */
#if !defined (PARSER_DEFS_H)
#define PARSER_DEFS_H 1
#include "vec.h"
#include "expression.h"
struct block;
struct language_defn;
struct internalvar;
extern int parser_debug;
#define parse_gdbarch(ps) ((ps)->expout->gdbarch)
#define parse_language(ps) ((ps)->expout->language_defn)
struct parser_state
{
/* The expression related to this parser state. */
struct expression *expout;
/* The size of the expression above. */
size_t expout_size;
/* The number of elements already in the expression. This is used
to know where to put new elements. */
size_t expout_ptr;
};
/* If this is nonzero, this block is used as the lexical context
for symbol names. */
extern const struct block *expression_context_block;
/* If expression_context_block is non-zero, then this is the PC within
the block that we want to evaluate expressions at. When debugging
C or C++ code, we use this to find the exact line we're at, and
then look up the macro definitions active at that point. */
extern CORE_ADDR expression_context_pc;
/* The innermost context required by the stack and register variables
we've encountered so far. */
extern const struct block *innermost_block;
/* Number of arguments seen so far in innermost function call. */
extern int arglist_len;
/* A string token, either a char-string or bit-string. Char-strings are
used, for example, for the names of symbols. */
struct stoken
{
/* Pointer to first byte of char-string or first bit of bit-string. */
const char *ptr;
/* Length of string in bytes for char-string or bits for bit-string. */
int length;
};
struct typed_stoken
{
/* A language-specific type field. */
int type;
/* Pointer to first byte of char-string or first bit of bit-string. */
char *ptr;
/* Length of string in bytes for char-string or bits for bit-string. */
int length;
};
struct stoken_vector
{
int len;
struct typed_stoken *tokens;
};
struct ttype
{
struct stoken stoken;
struct type *type;
};
struct symtoken
{
struct stoken stoken;
struct block_symbol sym;
int is_a_field_of_this;
};
struct objc_class_str
{
struct stoken stoken;
struct type *type;
int theclass;
};
typedef struct type *type_ptr;
DEF_VEC_P (type_ptr);
/* For parsing of complicated types.
An array should be preceded in the list by the size of the array. */
enum type_pieces
{
tp_end = -1,
tp_pointer,
tp_reference,
tp_rvalue_reference,
tp_array,
tp_function,
tp_function_with_arguments,
tp_const,
tp_volatile,
tp_space_identifier,
tp_type_stack
};
/* The stack can contain either an enum type_pieces or an int. */
union type_stack_elt
{
enum type_pieces piece;
int int_val;
struct type_stack *stack_val;
VEC (type_ptr) *typelist_val;
};
/* The type stack is an instance of this structure. */
struct type_stack
{
/* Elements on the stack. */
union type_stack_elt *elements;
/* Current stack depth. */
int depth;
/* Allocated size of stack. */
int size;
};
/* Helper function to initialize the expout, expout_size, expout_ptr
trio inside PS before it is used to store expression elements created
during the parsing of an expression. INITIAL_SIZE is the initial size of
the expout array. LANG is the language used to parse the expression.
And GDBARCH is the gdbarch to use during parsing. */
extern void initialize_expout (struct parser_state *ps,
size_t initial_size,
const struct language_defn *lang,
struct gdbarch *gdbarch);
/* Helper function that reallocates the EXPOUT inside PS in order to
eliminate any unused space. It is generally used when the expression
has just been parsed and created. */
extern void reallocate_expout (struct parser_state *ps);
/* Reverse an expression from suffix form (in which it is constructed)
to prefix form (in which we can conveniently print or execute it).
Ordinarily this always returns -1. However, if EXPOUT_LAST_STRUCT
is not -1 (i.e., we are trying to complete a field name), it will
return the index of the subexpression which is the left-hand-side
of the struct operation at EXPOUT_LAST_STRUCT. */
extern int prefixify_expression (struct expression *expr);
extern void write_exp_elt_opcode (struct parser_state *, enum exp_opcode);
extern void write_exp_elt_sym (struct parser_state *, struct symbol *);
extern void write_exp_elt_longcst (struct parser_state *, LONGEST);
extern void write_exp_elt_floatcst (struct parser_state *, const gdb_byte *);
extern void write_exp_elt_type (struct parser_state *, struct type *);
extern void write_exp_elt_intern (struct parser_state *, struct internalvar *);
extern void write_exp_string (struct parser_state *, struct stoken);
void write_exp_string_vector (struct parser_state *, int type,
struct stoken_vector *vec);
extern void write_exp_bitstring (struct parser_state *, struct stoken);
extern void write_exp_elt_block (struct parser_state *, const struct block *);
extern void write_exp_elt_objfile (struct parser_state *,
struct objfile *objfile);
extern void write_exp_msymbol (struct parser_state *,
struct bound_minimal_symbol);
extern void write_dollar_variable (struct parser_state *, struct stoken str);
extern void mark_struct_expression (struct parser_state *);
extern const char *find_template_name_end (const char *);
extern void start_arglist (void);
extern int end_arglist (void);
extern char *copy_name (struct stoken);
extern void insert_type (enum type_pieces);
extern void push_type (enum type_pieces);
extern void push_type_int (int);
extern void insert_type_address_space (struct parser_state *, char *);
extern enum type_pieces pop_type (void);
extern int pop_type_int (void);
extern struct type_stack *get_type_stack (void);
extern struct type_stack *append_type_stack (struct type_stack *to,
struct type_stack *from);
extern void push_type_stack (struct type_stack *stack);
extern void type_stack_cleanup (void *arg);
extern void push_typelist (VEC (type_ptr) *typelist);
extern int dump_subexp (struct expression *, struct ui_file *, int);
extern int dump_subexp_body_standard (struct expression *,
struct ui_file *, int);
extern void operator_length (const struct expression *, int, int *, int *);
extern void operator_length_standard (const struct expression *, int, int *,
int *);
extern int operator_check_standard (struct expression *exp, int pos,
int (*objfile_func)
(struct objfile *objfile, void *data),
void *data);
extern const char *op_name_standard (enum exp_opcode);
extern struct type *follow_types (struct type *);
extern type_instance_flags follow_type_instance_flags ();
extern void null_post_parser (struct expression **, int);
extern bool parse_float (const char *p, int len,
const struct type *type, gdb_byte *data);
/* During parsing of a C expression, the pointer to the next character
is in this variable. */
extern const char *lexptr;
/* After a token has been recognized, this variable points to it.
Currently used only for error reporting. */
extern const char *prev_lexptr;
/* Current depth in parentheses within the expression. */
extern int paren_depth;
/* Nonzero means stop parsing on first comma (if not within parentheses). */
extern int comma_terminates;
/* These codes indicate operator precedences for expression printing,
least tightly binding first. */
/* Adding 1 to a precedence value is done for binary operators,
on the operand which is more tightly bound, so that operators
of equal precedence within that operand will get parentheses. */
/* PREC_HYPER and PREC_ABOVE_COMMA are not the precedence of any operator;
they are used as the "surrounding precedence" to force
various kinds of things to be parenthesized. */
enum precedence
{
PREC_NULL, PREC_COMMA, PREC_ABOVE_COMMA, PREC_ASSIGN, PREC_LOGICAL_OR,
PREC_LOGICAL_AND, PREC_BITWISE_IOR, PREC_BITWISE_AND, PREC_BITWISE_XOR,
PREC_EQUAL, PREC_ORDER, PREC_SHIFT, PREC_ADD, PREC_MUL, PREC_REPEAT,
PREC_HYPER, PREC_PREFIX, PREC_SUFFIX, PREC_BUILTIN_FUNCTION
};
/* Table mapping opcodes into strings for printing operators
and precedences of the operators. */
struct op_print
{
const char *string;
enum exp_opcode opcode;
/* Precedence of operator. These values are used only by comparisons. */
enum precedence precedence;
/* For a binary operator: 1 iff right associate.
For a unary operator: 1 iff postfix. */
int right_assoc;
};
/* Information needed to print, prefixify, and evaluate expressions for
a given language. */
struct exp_descriptor
{
/* Print subexpression. */
void (*print_subexp) (struct expression *, int *, struct ui_file *,
enum precedence);
/* Returns number of exp_elements needed to represent an operator and
the number of subexpressions it takes. */
void (*operator_length) (const struct expression*, int, int*, int *);
/* Call OBJFILE_FUNC for any objfile found being referenced by the
single operator of EXP at position POS. Operator parameters are
located at positive (POS + number) offsets in EXP. OBJFILE_FUNC
should never be called with NULL OBJFILE. OBJFILE_FUNC should
get passed an arbitrary caller supplied DATA pointer. If it
returns non-zero value then (any other) non-zero value should be
immediately returned to the caller. Otherwise zero should be
returned. */
int (*operator_check) (struct expression *exp, int pos,
int (*objfile_func) (struct objfile *objfile,
void *data),
void *data);
/* Name of this operator for dumping purposes.
The returned value should never be NULL, even if EXP_OPCODE is
an unknown opcode (a string containing an image of the numeric
value of the opcode can be returned, for instance). */
const char *(*op_name) (enum exp_opcode);
/* Dump the rest of this (prefix) expression after the operator
itself has been printed. See dump_subexp_body_standard in
(expprint.c). */
int (*dump_subexp_body) (struct expression *, struct ui_file *, int);
/* Evaluate an expression. */
struct value *(*evaluate_exp) (struct type *, struct expression *,
int *, enum noside);
};
/* Default descriptor containing standard definitions of all
elements. */
extern const struct exp_descriptor exp_descriptor_standard;
/* Functions used by language-specific extended operators to (recursively)
print/dump subexpressions. */
extern void print_subexp (struct expression *, int *, struct ui_file *,
enum precedence);
extern void print_subexp_standard (struct expression *, int *,
struct ui_file *, enum precedence);
/* Function used to avoid direct calls to fprintf
in the code generated by the bison parser. */
extern void parser_fprintf (FILE *, const char *, ...) ATTRIBUTE_PRINTF (2, 3);
extern int exp_uses_objfile (struct expression *exp, struct objfile *objfile);
extern void mark_completion_tag (enum type_code, const char *ptr,
int length);
/* Reallocate the `expout' pointer inside PS so that it can accommodate
at least LENELT expression elements. This function does nothing if
there is enough room for the elements. */
extern void increase_expout_size (struct parser_state *ps, size_t lenelt);
#endif /* PARSER_DEFS_H */
Reference in New Issue View Git Blame Copy Permalink