diff options
Diffstat (limited to 'gdb/value.h')
| -rw-r--r-- | gdb/value.h | 320 |
1 files changed, 163 insertions, 157 deletions
diff --git a/gdb/value.h b/gdb/value.h index 54854e5..254c82f 100644 --- a/gdb/value.h +++ b/gdb/value.h @@ -1,4 +1,5 @@ /* Definitions for values of C expressions, for GDB. + Copyright 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003 Free Software Foundation, Inc. @@ -23,105 +24,109 @@ #if !defined (VALUE_H) #define VALUE_H 1 -struct ui_file; +#include "doublest.h" + +struct block; struct expression; +struct regcache; struct symbol; struct type; -struct regcache; -struct block; - -#include "doublest.h" +struct ui_file; -/* - * The structure which defines the type of a value. It should never - * be possible for a program lval value to survive over a call to the inferior - * (ie to be put into the history list or an internal variable). - */ +/* The structure which defines the type of a value. It should never + be possible for a program lval value to survive over a call to the + inferior (i.e. to be put into the history list or an internal + variable). */ struct value +{ + /* Type of value; either not an lval, or one of the various + different possible kinds of lval. */ + enum lval_type lval; + + /* Is it modifiable? Only relevant if lval != not_lval. */ + int modifiable; + + /* Location of value (if lval). */ + union { - /* Type of value; either not an lval, or one of the various - different possible kinds of lval. */ - enum lval_type lval; - /* Is it modifiable? Only relevant if lval != not_lval. */ - int modifiable; - /* Location of value (if lval). */ - union - { - /* If lval == lval_memory, this is the address in the inferior. - If lval == lval_register, this is the byte offset into the - registers structure. */ - CORE_ADDR address; - /* Pointer to internal variable. */ - struct internalvar *internalvar; - /* Number of register. Only used with - lval_reg_frame_relative. */ - int regnum; - } - location; - /* Describes offset of a value within lval of a structure in bytes. - If lval == lval_memory, this is an offset to the address. - If lval == lval_register, this is a further offset from - location.address within the registers structure. - Note also the member embedded_offset below. */ - int offset; - /* Only used for bitfields; number of bits contained in them. */ - int bitsize; - /* Only used for bitfields; position of start of field. - For BITS_BIG_ENDIAN=0 targets, it is the position of the LSB. - For BITS_BIG_ENDIAN=1 targets, it is the position of the MSB. */ + /* If lval == lval_memory, this is the address in the inferior. + If lval == lval_register, this is the byte offset into the + registers structure. */ + CORE_ADDR address; + + /* Pointer to internal variable. */ + struct internalvar *internalvar; + + /* Number of register. Only used with lval_reg_frame_relative. */ + int regnum; + } location; + + /* Describes offset of a value within lval of a structure in bytes. + If lval == lval_memory, this is an offset to the address. + If lval == lval_register, this is a further offset from + location.address within the registers structure. + Note also the member embedded_offset below. */ + int offset; + + /* Only used for bitfields; number of bits contained in them. */ + int bitsize; + + /* Only used for bitfields; position of start of field. + For BITS_BIG_ENDIAN=0 targets, it is the position of the LSB. + For BITS_BIG_ENDIAN=1 targets, it is the position of the MSB. */ int bitpos; - /* Frame value is relative to. In practice, this address is only - used if the value is stored in several registers in other than - the current frame, and these registers have not all been saved - at the same place in memory. This will be described in the - lval enum above as "lval_reg_frame_relative". */ - CORE_ADDR frame_addr; - - /* Type of the value. */ - struct type *type; - - /* If a value represents a C++ object, then the `type' field gives - the object's compile-time type. If the object actually belongs - to some class derived from `type', perhaps with other base - classes and additional members, then `type' is just a subobject - of the real thing, and the full object is probably larger than - `type' would suggest. - - If `type' is a dynamic class (i.e. one with a vtable), then GDB - can actually determine the object's run-time type by looking at - the run-time type information in the vtable. When this - information is available, we may elect to read in the entire - object, for several reasons: - - - When printing the value, the user would probably rather see - the full object, not just the limited portion apparent from - the compile-time type. - - - If `type' has virtual base classes, then even printing - `type' alone may require reaching outside the `type' - portion of the object to wherever the virtual base class - has been stored. - - When we store the entire object, `enclosing_type' is the - run-time type --- the complete object --- and `embedded_offset' - is the offset of `type' within that larger type, in bytes. The - VALUE_CONTENTS macro takes `embedded_offset' into account, so - most GDB code continues to see the `type' portion of the value, - just as the inferior would. - - If `type' is a pointer to an object, then `enclosing_type' is a - pointer to the object's run-time type, and `pointed_to_offset' - is the offset in bytes from the full object to the pointed-to - object --- that is, the value `embedded_offset' would have if - we followed the pointer and fetched the complete object. (I - don't really see the point. Why not just determine the - run-time type when you indirect, and avoid the special case? - The contents don't matter until you indirect anyway.) - - If we're not doing anything fancy, `enclosing_type' is equal to - `type', and `embedded_offset' is zero, so everything works - normally. */ + + /* Frame value is relative to. In practice, this address is only + used if the value is stored in several registers in other than + the current frame, and these registers have not all been saved + at the same place in memory. This will be described in the + lval enum above as "lval_reg_frame_relative". */ + CORE_ADDR frame_addr; + + /* Type of the value. */ + struct type *type; + + /* If a value represents a C++ object, then the `type' field gives + the object's compile-time type. If the object actually belongs + to some class derived from `type', perhaps with other base + classes and additional members, then `type' is just a subobject + of the real thing, and the full object is probably larger than + `type' would suggest. + + If `type' is a dynamic class (i.e. one with a vtable), then GDB + can actually determine the object's run-time type by looking at + the run-time type information in the vtable. When this + information is available, we may elect to read in the entire + object, for several reasons: + + - When printing the value, the user would probably rather see the + full object, not just the limited portion apparent from the + compile-time type. + + - If `type' has virtual base classes, then even printing `type' + alone may require reaching outside the `type' portion of the + object to wherever the virtual base class has been stored. + + When we store the entire object, `enclosing_type' is the run-time + type -- the complete object -- and `embedded_offset' is the + offset of `type' within that larger type, in bytes. The + VALUE_CONTENTS macro takes `embedded_offset' into account, so + most GDB code continues to see the `type' portion of the value, + just as the inferior would. + + If `type' is a pointer to an object, then `enclosing_type' is a + pointer to the object's run-time type, and `pointed_to_offset' is + the offset in bytes from the full object to the pointed-to object + -- that is, the value `embedded_offset' would have if we + followed the pointer and fetched the complete object. (I don't + really see the point. Why not just determine the run-time type + when you indirect, and avoid the special case? The contents + don't matter until you indirect anyway.) + + If we're not doing anything fancy, `enclosing_type' is equal to + `type', and `embedded_offset' is zero, so everything works + normally. */ struct type *enclosing_type; int embedded_offset; int pointed_to_offset; @@ -134,10 +139,11 @@ struct value /* Register number if the value is from a register. */ short regno; - /* If zero, contents of this value are in the contents field. - If nonzero, contents are in inferior memory at address - in the location.address field plus the offset field - (and the lval field should be lval_memory). + + /* If zero, contents of this value are in the contents field. If + nonzero, contents are in inferior memory at address in the + location.address field plus the offset field (and the lval + field should be lval_memory). WARNING: This field is used by the code which handles watchpoints (see breakpoint.c) to decide whether a particular @@ -150,53 +156,59 @@ struct value lazy flag is set and reset, be sure to consider this use as well! */ char lazy; + /* If nonzero, this is the value of a variable which does not actually exist in the program. */ char optimized_out; + /* The BFD section associated with this value. */ asection *bfd_section; + /* Actual contents of the value. For use of this value; setting it uses the stuff above. Not valid if lazy is nonzero. Target byte-order. We force it to be aligned properly for any possible value. Note that a value therefore extends beyond what is declared here. */ union - { - long contents[1]; - DOUBLEST force_doublest_align; - LONGEST force_longest_align; - CORE_ADDR force_core_addr_align; - void *force_pointer_align; - } - aligner; - /* Do not add any new members here -- contents above will trash them */ - }; + { + long contents[1]; + DOUBLEST force_doublest_align; + LONGEST force_longest_align; + CORE_ADDR force_core_addr_align; + void *force_pointer_align; + } aligner; + /* Do not add any new members here -- contents above will trash them. */ +}; #define VALUE_TYPE(val) (val)->type #define VALUE_ENCLOSING_TYPE(val) (val)->enclosing_type #define VALUE_LAZY(val) (val)->lazy + /* VALUE_CONTENTS and VALUE_CONTENTS_RAW both return the address of - the gdb buffer used to hold a copy of the contents of the lval. - VALUE_CONTENTS is used when the contents of the buffer are needed -- - it uses value_fetch_lazy() to load the buffer from the process being - debugged if it hasn't already been loaded. VALUE_CONTENTS_RAW is - used when data is being stored into the buffer, or when it is - certain that the contents of the buffer are valid. + the gdb buffer used to hold a copy of the contents of the lval. + VALUE_CONTENTS is used when the contents of the buffer are needed + -- it uses value_fetch_lazy() to load the buffer from the process + being debugged if it hasn't already been loaded. + VALUE_CONTENTS_RAW is used when data is being stored into the + buffer, or when it is certain that the contents of the buffer are + valid. + Note: The contents pointer is adjusted by the offset required to get to the real subobject, if the value happens to represent - something embedded in a larger run-time object. */ + something embedded in a larger run-time object. */ -#define VALUE_CONTENTS_RAW(val) ((char *) (val)->aligner.contents + (val)->embedded_offset) -#define VALUE_CONTENTS(val) ((void)(VALUE_LAZY(val) && value_fetch_lazy(val)),\ - VALUE_CONTENTS_RAW(val)) +#define VALUE_CONTENTS_RAW(val) \ + ((char *) (val)->aligner.contents + (val)->embedded_offset) +#define VALUE_CONTENTS(val) \ + ((void)(VALUE_LAZY(val) && value_fetch_lazy(val)), VALUE_CONTENTS_RAW(val)) /* The ALL variants of the above two macros do not adjust the returned - pointer by the embedded_offset value. */ + pointer by the embedded_offset value. */ #define VALUE_CONTENTS_ALL_RAW(val) ((char *) (val)->aligner.contents) -#define VALUE_CONTENTS_ALL(val) ((void) (VALUE_LAZY(val) && value_fetch_lazy(val)),\ - VALUE_CONTENTS_ALL_RAW(val)) - +#define VALUE_CONTENTS_ALL(val) \ + ((void) (VALUE_LAZY(val) && value_fetch_lazy(val)), \ + VALUE_CONTENTS_ALL_RAW(val)) extern int value_fetch_lazy (struct value *val); @@ -215,16 +227,17 @@ extern int value_fetch_lazy (struct value *val); #define VALUE_POINTED_TO_OFFSET(val) ((val)->pointed_to_offset) #define VALUE_BFD_SECTION(val) ((val)->bfd_section) -/* Convert a REF to the object referenced. */ +/* Convert a REF to the object referenced. */ -#define COERCE_REF(arg) \ -do { struct type *value_type_arg_tmp = check_typedef (VALUE_TYPE (arg));\ - if (TYPE_CODE (value_type_arg_tmp) == TYPE_CODE_REF) \ - arg = value_at_lazy (TYPE_TARGET_TYPE (value_type_arg_tmp), \ - unpack_pointer (VALUE_TYPE (arg), \ - VALUE_CONTENTS (arg)), \ - VALUE_BFD_SECTION (arg)); \ - } while (0) +#define COERCE_REF(arg) \ + do { \ + struct type *value_type_arg_tmp = check_typedef (VALUE_TYPE (arg)); \ + if (TYPE_CODE (value_type_arg_tmp) == TYPE_CODE_REF) \ + arg = value_at_lazy (TYPE_TARGET_TYPE (value_type_arg_tmp), \ + unpack_pointer (VALUE_TYPE (arg), \ + VALUE_CONTENTS (arg)), \ + VALUE_BFD_SECTION (arg)); \ + } while (0) /* If ARG is an array, convert it to a pointer. If ARG is an enum, convert it to an integer. @@ -232,17 +245,18 @@ do { struct type *value_type_arg_tmp = check_typedef (VALUE_TYPE (arg));\ References are dereferenced. */ -#define COERCE_ARRAY(arg) \ -do { COERCE_REF(arg); \ - if (current_language->c_style_arrays \ - && TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_ARRAY) \ - arg = value_coerce_array (arg); \ - if (TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_FUNC) \ - arg = value_coerce_function (arg); \ -} while (0) +#define COERCE_ARRAY(arg) \ + do { \ + COERCE_REF(arg); \ + if (current_language->c_style_arrays \ + && TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_ARRAY) \ + arg = value_coerce_array (arg); \ + if (TYPE_CODE (VALUE_TYPE (arg)) == TYPE_CODE_FUNC) \ + arg = value_coerce_function (arg); \ + } while (0) -#define COERCE_NUMBER(arg) \ - do { COERCE_ARRAY(arg); COERCE_ENUM(arg); } while (0) +#define COERCE_NUMBER(arg) \ + do { COERCE_ARRAY(arg); COERCE_ENUM(arg); } while (0) /* NOTE: cagney/2002-12-17: This macro was handling a chill language problem but that language has gone away. */ @@ -250,22 +264,23 @@ do { COERCE_REF(arg); \ /* If ARG is an enum, convert it to an integer. */ -#define COERCE_ENUM(arg) { \ - if (TYPE_CODE (check_typedef (VALUE_TYPE (arg))) == TYPE_CODE_ENUM) \ - arg = value_cast (builtin_type_unsigned_int, arg); \ -} +#define COERCE_ENUM(arg) \ + do { \ + if (TYPE_CODE (check_typedef (VALUE_TYPE (arg))) == TYPE_CODE_ENUM) \ + arg = value_cast (builtin_type_unsigned_int, arg); \ + } while (0) /* Internal variables (variables for convenience of use of debugger) are recorded as a chain of these structures. */ struct internalvar - { - struct internalvar *next; - char *name; - struct value *value; - }; +{ + struct internalvar *next; + char *name; + struct value *value; +}; -/* Pointer to member function. Depends on compiler implementation. */ +/* Pointer to member function. Depends on compiler implementation. */ #define METHOD_PTR_IS_VIRTUAL(ADDR) ((ADDR) & 0x80000000) #define METHOD_PTR_FROM_VOFFSET(OFFSET) (0x80000000 + (OFFSET)) @@ -282,32 +297,23 @@ struct fn_field; extern void print_address_demangle (CORE_ADDR, struct ui_file *, int); extern LONGEST value_as_long (struct value *val); - extern DOUBLEST value_as_double (struct value *val); - extern CORE_ADDR value_as_address (struct value *val); extern LONGEST unpack_long (struct type *type, const char *valaddr); - extern DOUBLEST unpack_double (struct type *type, const char *valaddr, int *invp); - extern CORE_ADDR unpack_pointer (struct type *type, const char *valaddr); - extern LONGEST unpack_field_as_long (struct type *type, const char *valaddr, int fieldno); extern struct value *value_from_longest (struct type *type, LONGEST num); - extern struct value *value_from_pointer (struct type *type, CORE_ADDR addr); - extern struct value *value_from_double (struct type *type, DOUBLEST num); - extern struct value *value_from_string (char *string); extern struct value *value_at (struct type *type, CORE_ADDR addr, asection * sect); - extern struct value *value_at_lazy (struct type *type, CORE_ADDR addr, asection * sect); |