X-Git-Url: https://git.libre-soc.org/?a=blobdiff_plain;f=gdb%2Fexpression.h;h=3ba68a2db93eaec6a4014551acf508a6a628acab;hb=1d2eeb660f0885807320792ee18c033b34522225;hp=0c4dc7bae1750471475c6942ef920faedc2c970d;hpb=1ab8280d7dbe01f51929d221621d38450f31895d;p=binutils-gdb.git diff --git a/gdb/expression.h b/gdb/expression.h index 0c4dc7bae17..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) 1986-2020 Free Software Foundation, Inc. + Copyright (C) 1986-2022 Free Software Foundation, Inc. This file is part of GDB. @@ -40,21 +40,6 @@ enum innermost_block_tracker_type DEF_ENUM_FLAGS_TYPE (enum innermost_block_tracker_type, innermost_block_tracker_types); -/* Definitions for saved C expressions. */ - -/* 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 : uint8_t { #define OP(name) name , @@ -62,64 +47,211 @@ enum exp_opcode : uint8_t #include "std-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; - struct minimal_symbol *msymbol; - LONGEST longconst; - gdb_byte floatconst[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 *, struct gdbarch *, size_t); - ~expression (); + expression (const struct language_defn *lang, struct gdbarch *arch) + : language_defn (lang), + gdbarch (arch) + { + } + DISABLE_COPY_AND_ASSIGN (expression); - void resize (size_t); + /* 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); /* Language it was entered in. */ const struct language_defn *language_defn; /* Architecture it was parsed in. */ struct gdbarch *gdbarch; - int nelts = 0; - union exp_element *elts; + expr::operation_up op; }; typedef std::unique_ptr expression_up; -/* Macros for converting between number of expression elements and bytes - to store that many expression elements. */ - -#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)) - /* From parse.c */ class innermost_block_tracker; extern expression_up parse_expression (const char *, - innermost_block_tracker * = nullptr); + innermost_block_tracker * = nullptr, + bool void_context_p = false); extern expression_up parse_expression_with_language (const char *string, enum language lang); -extern struct type *parse_expression_for_completion - (const char *, gdb::unique_xmalloc_ptr *, enum type_code *); + +class completion_tracker; + +/* 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; + + virtual ~expr_completion_base () = default; +}; + +extern expression_up parse_expression_for_completion + (const char *, std::unique_ptr *completer); class innermost_block_tracker; extern expression_up parse_exp_1 (const char **, CORE_ADDR pc, @@ -128,31 +260,6 @@ extern expression_up parse_exp_1 (const char **, CORE_ADDR pc, /* From eval.c */ -/* Values of NOSIDE argument to eval_subexp. */ - -enum noside - { - EVAL_NORMAL, - EVAL_SKIP, /* Only effect is to increment pos. - Return type information where - possible. */ - 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. */ - }; - -extern struct value *evaluate_subexp_standard - (struct type *, struct expression *, int *, enum noside); - /* 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. @@ -168,14 +275,8 @@ extern struct value *evaluate_subexp_do_call (expression *exp, /* From expprint.c */ -extern void print_expression (struct expression *, struct ui_file *); - extern const char *op_name (enum exp_opcode opcode); -extern const char *op_string (enum exp_opcode); - -extern void dump_raw_expression (struct expression *, - struct ui_file *, const char *); extern void dump_prefix_expression (struct expression *, struct ui_file *); /* In an OP_RANGE expression, either bound could be empty, indicating