X-Git-Url: https://git.libre-soc.org/?a=blobdiff_plain;f=gdb%2Fexpression.h;h=3ba68a2db93eaec6a4014551acf508a6a628acab;hb=1d2eeb660f0885807320792ee18c033b34522225;hp=eea47dc6b2adb891a0434708767b67e61f8ac1de;hpb=bbc13ae3db19a3276ba029c838682f81d10f859a;p=binutils-gdb.git diff --git a/gdb/expression.h b/gdb/expression.h index eea47dc6b2a..3ba68a2db93 100644 --- a/gdb/expression.h +++ b/gdb/expression.h @@ -1,6 +1,6 @@ /* Definitions for expressions stored in reversed prefix form, for GDB. - Copyright (C) 1986-2013 Free Software Foundation, Inc. + Copyright (C) 1986-2022 Free Software Foundation, Inc. This file is part of GDB. @@ -20,130 +20,290 @@ #if !defined (EXPRESSION_H) #define EXPRESSION_H 1 +#include "gdbtypes.h" -#include "symtab.h" /* Needed for "struct block" type. */ -#include "doublest.h" /* Needed for DOUBLEST. */ +/* While parsing expressions we need to track the innermost lexical block + that we encounter. In some situations we need to track the innermost + block just for symbols, and in other situations we want to track the + innermost block for symbols and registers. These flags are used by the + innermost block tracker to control which blocks we consider for the + innermost block. These flags can be combined together as needed. */ +enum innermost_block_tracker_type +{ + /* Track the innermost block for symbols within an expression. */ + INNERMOST_BLOCK_FOR_SYMBOLS = (1 << 0), -/* Definitions for saved C expressions. */ + /* Track the innermost block for registers within an expression. */ + INNERMOST_BLOCK_FOR_REGISTERS = (1 << 1) +}; +DEF_ENUM_FLAGS_TYPE (enum innermost_block_tracker_type, + innermost_block_tracker_types); -/* An expression is represented as a vector of union exp_element's. - Each exp_element is an opcode, except that some opcodes cause - the following exp_element to be treated as a long or double constant - or as a variable. The opcodes are obeyed, using a stack for temporaries. - The value is left on the temporary stack at the end. */ - -/* When it is necessary to include a string, - it can occupy as many exp_elements as it needs. - We find the length of the string using strlen, - divide to find out how many exp_elements are used up, - and skip that many. Strings, like numbers, are indicated - by the preceding opcode. */ - -enum exp_opcode +enum exp_opcode : uint8_t { #define OP(name) name , #include "std-operator.def" - /* First extension operator. Individual language modules define extra - operators in *.def include files below with numbers higher than - OP_EXTENDED0. */ - OP (OP_EXTENDED0) - -/* Language specific operators. */ -#include "ada-operator.def" - #undef OP - - /* Existing only to swallow the last comma (',') from last .inc file. */ - OP_UNUSED_LAST }; -union exp_element +/* Values of NOSIDE argument to eval_subexp. */ + +enum noside { - enum exp_opcode opcode; - struct symbol *symbol; - LONGEST longconst; - DOUBLEST doubleconst; - gdb_byte decfloatconst[16]; - /* Really sizeof (union exp_element) characters (or less for the last - element of a string). */ - char string; - struct type *type; - struct internalvar *internalvar; - const struct block *block; - struct objfile *objfile; + EVAL_NORMAL, + EVAL_AVOID_SIDE_EFFECTS /* Don't modify any variables or + call any functions. The value + returned will have the correct + type, and will have an + approximately correct lvalue + type (inaccuracy: anything that is + listed as being in a register in + the function in which it was + declared will be lval_register). + Ideally this would not even read + target memory, but currently it + does in many situations. */ }; +struct expression; +struct agent_expr; +struct axs_value; +struct type; +struct ui_file; + +namespace expr +{ + +class operation; +typedef std::unique_ptr operation_up; + +/* Base class for an operation. An operation is a single component of + an expression. */ + +class operation +{ +protected: + + operation () = default; + DISABLE_COPY_AND_ASSIGN (operation); + +public: + + virtual ~operation () = default; + + /* Evaluate this operation. */ + virtual value *evaluate (struct type *expect_type, + struct expression *exp, + enum noside noside) = 0; + + /* Evaluate this operation in a context where C-like coercion is + needed. */ + virtual value *evaluate_with_coercion (struct expression *exp, + enum noside noside) + { + return evaluate (nullptr, exp, noside); + } + + /* Evaluate this expression in the context of a cast to + EXPECT_TYPE. */ + virtual value *evaluate_for_cast (struct type *expect_type, + struct expression *exp, + enum noside noside); + + /* Evaluate this expression in the context of a sizeof + operation. */ + virtual value *evaluate_for_sizeof (struct expression *exp, + enum noside noside); + + /* Evaluate this expression in the context of an address-of + operation. Must return the address. */ + virtual value *evaluate_for_address (struct expression *exp, + enum noside noside); + + /* Evaluate a function call, with this object as the callee. + EXPECT_TYPE, EXP, and NOSIDE have the same meaning as in + 'evaluate'. ARGS holds the operations that should be evaluated + to get the arguments to the call. */ + virtual value *evaluate_funcall (struct type *expect_type, + struct expression *exp, + enum noside noside, + const std::vector &args) + { + /* Defer to the helper overload. */ + return evaluate_funcall (expect_type, exp, noside, nullptr, args); + } + + /* True if this is a constant expression. */ + virtual bool constant_p () const + { return false; } + + /* Return true if this operation uses OBJFILE (and will become + dangling when OBJFILE is unloaded), otherwise return false. + OBJFILE must not be a separate debug info file. */ + virtual bool uses_objfile (struct objfile *objfile) const + { return false; } + + /* Generate agent expression bytecodes for this operation. */ + void generate_ax (struct expression *exp, struct agent_expr *ax, + struct axs_value *value, + struct type *cast_type = nullptr); + + /* Return the opcode that is implemented by this operation. */ + virtual enum exp_opcode opcode () const = 0; + + /* Print this operation to STREAM. */ + virtual void dump (struct ui_file *stream, int depth) const = 0; + + /* Call to indicate that this is the outermost operation in the + expression. This should almost never be overridden. */ + virtual void set_outermost () { } + +protected: + + /* A helper overload that wraps evaluate_subexp_do_call. */ + value *evaluate_funcall (struct type *expect_type, + struct expression *exp, + enum noside noside, + const char *function_name, + const std::vector &args); + + /* Called by generate_ax to do the work for this particular + operation. */ + virtual void do_generate_ax (struct expression *exp, + struct agent_expr *ax, + struct axs_value *value, + struct type *cast_type) + { + error (_("Cannot translate to agent expression")); + } +}; + +/* A helper function for creating an operation_up, given a type. */ +template +operation_up +make_operation (Arg... args) +{ + return operation_up (new T (std::forward (args)...)); +} + +} + struct expression +{ + expression (const struct language_defn *lang, struct gdbarch *arch) + : language_defn (lang), + gdbarch (arch) { - const struct language_defn *language_defn; /* language it was - entered in. */ - struct gdbarch *gdbarch; /* architecture it was parsed in. */ - int nelts; - union exp_element elts[1]; - }; + } + + DISABLE_COPY_AND_ASSIGN (expression); + + /* Return the opcode for the outermost sub-expression of this + expression. */ + enum exp_opcode first_opcode () const + { + return op->opcode (); + } + + /* Evaluate the expression. EXPECT_TYPE is the context type of the + expression; normally this should be nullptr. NOSIDE controls how + evaluation is performed. */ + struct value *evaluate (struct type *expect_type, enum noside noside); -/* Macros for converting between number of expression elements and bytes - to store that many expression elements. */ + /* Language it was entered in. */ + const struct language_defn *language_defn; + /* Architecture it was parsed in. */ + struct gdbarch *gdbarch; + expr::operation_up op; +}; -#define EXP_ELEM_TO_BYTES(elements) \ - ((elements) * sizeof (union exp_element)) -#define BYTES_TO_EXP_ELEM(bytes) \ - (((bytes) + sizeof (union exp_element) - 1) / sizeof (union exp_element)) +typedef std::unique_ptr expression_up; /* From parse.c */ -extern struct expression *parse_expression (const char *); +class innermost_block_tracker; +extern expression_up parse_expression (const char *, + innermost_block_tracker * = nullptr, + bool void_context_p = false); -extern struct type *parse_expression_for_completion (char *, char **, - enum type_code *); +extern expression_up parse_expression_with_language (const char *string, + enum language lang); -extern struct expression *parse_exp_1 (const char **, CORE_ADDR pc, - const struct block *, int); -/* For use by parsers; set if we want to parse an expression and - attempt completion. */ -extern int parse_completion; +class completion_tracker; -/* The innermost context required by the stack and register variables - we've encountered so far. To use this, set it to NULL, then call - parse_, then look at it. */ -extern const struct block *innermost_block; +/* Base class for expression completion. An instance of this + represents a completion request from the parser. */ +struct expr_completion_base +{ + /* Perform this object's completion. EXP is the expression in which + the completion occurs. TRACKER is the tracker to update with the + results. Return true if completion was possible (even if no + completions were found), false to fall back to ordinary + expression completion (i.e., symbol names). */ + virtual bool complete (struct expression *exp, + completion_tracker &tracker) = 0; -/* From eval.c */ + virtual ~expr_completion_base () = default; +}; -/* Values of NOSIDE argument to eval_subexp. */ +extern expression_up parse_expression_for_completion + (const char *, std::unique_ptr *completer); -enum noside - { - EVAL_NORMAL, - EVAL_SKIP, /* Only effect is to increment pos. */ - EVAL_AVOID_SIDE_EFFECTS /* Don't modify any variables or - call any functions. The value - returned will have the correct - type, and will have an - approximately correct lvalue - type (inaccuracy: anything that is - listed as being in a register in - the function in which it was - declared will be lval_register). */ - }; +class innermost_block_tracker; +extern expression_up parse_exp_1 (const char **, CORE_ADDR pc, + const struct block *, int, + innermost_block_tracker * = nullptr); -extern struct value *evaluate_subexp_standard - (struct type *, struct expression *, int *, enum noside); +/* From eval.c */ -/* From expprint.c */ +/* Evaluate a function call. The function to be called is in CALLEE and + the arguments passed to the function are in ARGVEC. + FUNCTION_NAME is the name of the function, if known. + DEFAULT_RETURN_TYPE is used as the function's return type if the return + type is unknown. */ -extern void print_expression (struct expression *, struct ui_file *); +extern struct value *evaluate_subexp_do_call (expression *exp, + enum noside noside, + value *callee, + gdb::array_view argvec, + const char *function_name, + type *default_return_type); -extern char *op_name (struct expression *exp, enum exp_opcode opcode); +/* From expprint.c */ -extern char *op_string (enum exp_opcode); +extern const char *op_name (enum exp_opcode opcode); -extern void dump_raw_expression (struct expression *, - struct ui_file *, char *); extern void dump_prefix_expression (struct expression *, struct ui_file *); +/* In an OP_RANGE expression, either bound could be empty, indicating + that its value is by default that of the corresponding bound of the + array or string. Also, the upper end of the range can be exclusive + or inclusive. So we have six sorts of subrange. This enumeration + type is to identify this. */ + +enum range_flag : unsigned +{ + /* This is a standard range. Both the lower and upper bounds are + defined, and the bounds are inclusive. */ + RANGE_STANDARD = 0, + + /* The low bound was not given. */ + RANGE_LOW_BOUND_DEFAULT = 1 << 0, + + /* The high bound was not given. */ + RANGE_HIGH_BOUND_DEFAULT = 1 << 1, + + /* The high bound of this range is exclusive. */ + RANGE_HIGH_BOUND_EXCLUSIVE = 1 << 2, + + /* The range has a stride. */ + RANGE_HAS_STRIDE = 1 << 3, +}; + +DEF_ENUM_FLAGS_TYPE (enum range_flag, range_flags); + #endif /* !defined (EXPRESSION_H) */