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Diffstat (limited to 'gdb/valops.c')
| -rw-r--r-- | gdb/valops.c | 1478 |
1 files changed, 1478 insertions, 0 deletions
diff --git a/gdb/valops.c b/gdb/valops.c new file mode 100644 index 0000000..8031471 --- /dev/null +++ b/gdb/valops.c @@ -0,0 +1,1478 @@ +/* Perform non-arithmetic operations on values, for GDB. + Copyright (C) 1986, 1987, 1989 Free Software Foundation, Inc. + +This file is part of GDB. + +GDB 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 1, or (at your option) +any later version. + +GDB 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 GDB; see the file COPYING. If not, write to +the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ + +#include <stdio.h> +#include "defs.h" +#include "param.h" +#include "symtab.h" +#include "value.h" +#include "frame.h" +#include "inferior.h" +#include "gdbcore.h" +#include "target.h" + +#include <errno.h> + +/* Local functions. */ +static value search_struct_field (); + +/* Cast value ARG2 to type TYPE and return as a value. + More general than a C cast: accepts any two types of the same length, + and if ARG2 is an lvalue it can be cast into anything at all. */ +/* In C++, casts may change pointer representations. */ + +value +value_cast (type, arg2) + struct type *type; + register value arg2; +{ + register enum type_code code1; + register enum type_code code2; + register int scalar; + + /* Coerce arrays but not enums. Enums will work as-is + and coercing them would cause an infinite recursion. */ + if (TYPE_CODE (VALUE_TYPE (arg2)) != TYPE_CODE_ENUM) + COERCE_ARRAY (arg2); + + code1 = TYPE_CODE (type); + code2 = TYPE_CODE (VALUE_TYPE (arg2)); + scalar = (code2 == TYPE_CODE_INT || code2 == TYPE_CODE_FLT + || code2 == TYPE_CODE_ENUM); + + if (code1 == TYPE_CODE_FLT && scalar) + return value_from_double (type, value_as_double (arg2)); + else if ((code1 == TYPE_CODE_INT || code1 == TYPE_CODE_ENUM) + && (scalar || code2 == TYPE_CODE_PTR)) + return value_from_long (type, value_as_long (arg2)); + else if (TYPE_LENGTH (type) == TYPE_LENGTH (VALUE_TYPE (arg2))) + { + if (code1 == TYPE_CODE_PTR && code2 == TYPE_CODE_PTR) + { + /* Look in the type of the source to see if it contains the + type of the target as a superclass. If so, we'll need to + offset the pointer rather than just change its type. */ + struct type *t1 = TYPE_TARGET_TYPE (type); + struct type *t2 = TYPE_TARGET_TYPE (VALUE_TYPE (arg2)); + if (TYPE_CODE (t1) == TYPE_CODE_STRUCT + && TYPE_CODE (t2) == TYPE_CODE_STRUCT + && TYPE_NAME (t1) != 0) /* if name unknown, can't have supercl */ + { + value v = search_struct_field (type_name_no_tag (t1), + value_ind (arg2), 0, t2); + if (v) + { + v = value_addr (v); + VALUE_TYPE (v) = type; + return v; + } + } + /* No superclass found, just fall through to change ptr type. */ + } + VALUE_TYPE (arg2) = type; + return arg2; + } + else if (VALUE_LVAL (arg2) == lval_memory) + { + return value_at_lazy (type, VALUE_ADDRESS (arg2) + VALUE_OFFSET (arg2)); + } + else + { + error ("Invalid cast."); + return 0; + } +} + +/* Create a value of type TYPE that is zero, and return it. */ + +value +value_zero (type, lv) + struct type *type; + enum lval_type lv; +{ + register value val = allocate_value (type); + + bzero (VALUE_CONTENTS (val), TYPE_LENGTH (type)); + VALUE_LVAL (val) = lv; + + return val; +} + +/* Return a value with type TYPE located at ADDR. + + Call value_at only if the data needs to be fetched immediately; + if we can be 'lazy' and defer the fetch, perhaps indefinately, call + value_at_lazy instead. value_at_lazy simply records the address of + the data and sets the lazy-evaluation-required flag. The lazy flag + is tested in the VALUE_CONTENTS macro, which is used if and when + the contents are actually required. */ + +value +value_at (type, addr) + struct type *type; + CORE_ADDR addr; +{ + register value val = allocate_value (type); + + read_memory (addr, VALUE_CONTENTS_RAW (val), TYPE_LENGTH (type)); + + VALUE_LVAL (val) = lval_memory; + VALUE_ADDRESS (val) = addr; + + return val; +} + +/* Return a lazy value with type TYPE located at ADDR (cf. value_at). */ + +value +value_at_lazy (type, addr) + struct type *type; + CORE_ADDR addr; +{ + register value val = allocate_value (type); + + VALUE_LVAL (val) = lval_memory; + VALUE_ADDRESS (val) = addr; + VALUE_LAZY (val) = 1; + + return val; +} + +/* Called only from the VALUE_CONTENTS macro, if the current data for + a variable needs to be loaded into VALUE_CONTENTS(VAL). Fetches the + data from the user's process, and clears the lazy flag to indicate + that the data in the buffer is valid. + + This function returns a value because it is used in the VALUE_CONTENTS + macro as part of an expression, where a void would not work. The + value is ignored. */ + +int +value_fetch_lazy (val) + register value val; +{ + CORE_ADDR addr = VALUE_ADDRESS (val) + VALUE_OFFSET (val); + + read_memory (addr, VALUE_CONTENTS_RAW (val), + TYPE_LENGTH (VALUE_TYPE (val))); + VALUE_LAZY (val) = 0; + return 0; +} + + +/* Store the contents of FROMVAL into the location of TOVAL. + Return a new value with the location of TOVAL and contents of FROMVAL. */ + +value +value_assign (toval, fromval) + register value toval, fromval; +{ + register struct type *type = VALUE_TYPE (toval); + register value val; + char raw_buffer[MAX_REGISTER_RAW_SIZE]; + char virtual_buffer[MAX_REGISTER_VIRTUAL_SIZE]; + int use_buffer = 0; + + COERCE_ARRAY (fromval); + + if (VALUE_LVAL (toval) != lval_internalvar) + fromval = value_cast (type, fromval); + + /* If TOVAL is a special machine register requiring conversion + of program values to a special raw format, + convert FROMVAL's contents now, with result in `raw_buffer', + and set USE_BUFFER to the number of bytes to write. */ + + if (VALUE_REGNO (toval) >= 0 + && REGISTER_CONVERTIBLE (VALUE_REGNO (toval))) + { + int regno = VALUE_REGNO (toval); + if (VALUE_TYPE (fromval) != REGISTER_VIRTUAL_TYPE (regno)) + fromval = value_cast (REGISTER_VIRTUAL_TYPE (regno), fromval); + bcopy (VALUE_CONTENTS (fromval), virtual_buffer, + REGISTER_VIRTUAL_SIZE (regno)); + target_convert_from_virtual (regno, virtual_buffer, raw_buffer); + use_buffer = REGISTER_RAW_SIZE (regno); + } + + switch (VALUE_LVAL (toval)) + { + case lval_internalvar: + set_internalvar (VALUE_INTERNALVAR (toval), fromval); + break; + + case lval_internalvar_component: + set_internalvar_component (VALUE_INTERNALVAR (toval), + VALUE_OFFSET (toval), + VALUE_BITPOS (toval), + VALUE_BITSIZE (toval), + fromval); + break; + + case lval_memory: + if (VALUE_BITSIZE (toval)) + { + int v; /* FIXME, this won't work for large bitfields */ + read_memory (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval), + &v, sizeof v); + modify_field (&v, (int) value_as_long (fromval), + VALUE_BITPOS (toval), VALUE_BITSIZE (toval)); + write_memory (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval), + (char *)&v, sizeof v); + } + else if (use_buffer) + write_memory (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval), + raw_buffer, use_buffer); + else + write_memory (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval), + VALUE_CONTENTS (fromval), TYPE_LENGTH (type)); + break; + + case lval_register: + if (VALUE_BITSIZE (toval)) + { + int v; + + read_register_bytes (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval), + &v, sizeof v); + modify_field (&v, (int) value_as_long (fromval), + VALUE_BITPOS (toval), VALUE_BITSIZE (toval)); + write_register_bytes (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval), + &v, sizeof v); + } + else if (use_buffer) + write_register_bytes (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval), + raw_buffer, use_buffer); + else + write_register_bytes (VALUE_ADDRESS (toval) + VALUE_OFFSET (toval), + VALUE_CONTENTS (fromval), TYPE_LENGTH (type)); + break; + + case lval_reg_frame_relative: + { + /* value is stored in a series of registers in the frame + specified by the structure. Copy that value out, modify + it, and copy it back in. */ + int amount_to_copy = (VALUE_BITSIZE (toval) ? 1 : TYPE_LENGTH (type)); + int reg_size = REGISTER_RAW_SIZE (VALUE_FRAME_REGNUM (toval)); + int byte_offset = VALUE_OFFSET (toval) % reg_size; + int reg_offset = VALUE_OFFSET (toval) / reg_size; + int amount_copied; + char *buffer = (char *) alloca (amount_to_copy); + int regno; + FRAME frame; + + /* Figure out which frame this is in currently. */ + for (frame = get_current_frame (); + frame && FRAME_FP (frame) != VALUE_FRAME (toval); + frame = get_prev_frame (frame)) + ; + + if (!frame) + error ("Value being assigned to is no longer active."); + + amount_to_copy += (reg_size - amount_to_copy % reg_size); + + /* Copy it out. */ + for ((regno = VALUE_FRAME_REGNUM (toval) + reg_offset, + amount_copied = 0); + amount_copied < amount_to_copy; + amount_copied += reg_size, regno++) + { + get_saved_register (buffer + amount_copied, + (int *)NULL, (CORE_ADDR)NULL, + frame, regno, (enum lval_type *)NULL); + } + + /* Modify what needs to be modified. */ + if (VALUE_BITSIZE (toval)) + modify_field (buffer + byte_offset, + (int) value_as_long (fromval), + VALUE_BITPOS (toval), VALUE_BITSIZE (toval)); + else if (use_buffer) + bcopy (raw_buffer, buffer + byte_offset, use_buffer); + else + bcopy (VALUE_CONTENTS (fromval), buffer + byte_offset, + TYPE_LENGTH (type)); + + /* Copy it back. */ + for ((regno = VALUE_FRAME_REGNUM (toval) + reg_offset, + amount_copied = 0); + amount_copied < amount_to_copy; + amount_copied += reg_size, regno++) + { + enum lval_type lval; + CORE_ADDR addr; + int optim; + + /* Just find out where to put it. */ + get_saved_register ((char *)NULL, + &optim, &addr, frame, regno, &lval); + + if (optim) + error ("Attempt to assign to a value that was optimized out."); + if (lval == lval_memory) + write_memory (addr, buffer + amount_copied, reg_size); + else if (lval == lval_register) + write_register_bytes (addr, buffer + amount_copied, reg_size); + else + error ("Attempt to assign to an unmodifiable value."); + } + } + break; + + + default: + error ("Left side of = operation is not an lvalue."); + } + + /* Return a value just like TOVAL except with the contents of FROMVAL + (except in the case of the type if TOVAL is an internalvar). */ + + if (VALUE_LVAL (toval) == lval_internalvar + || VALUE_LVAL (toval) == lval_internalvar_component) + { + type = VALUE_TYPE (fromval); + } + + val = allocate_value (type); + bcopy (toval, val, VALUE_CONTENTS_RAW (val) - (char *) val); + bcopy (VALUE_CONTENTS (fromval), VALUE_CONTENTS_RAW (val), TYPE_LENGTH (type)); + VALUE_TYPE (val) = type; + + return val; +} + +/* Extend a value VAL to COUNT repetitions of its type. */ + +value +value_repeat (arg1, count) + value arg1; + int count; +{ + register value val; + + if (VALUE_LVAL (arg1) != lval_memory) + error ("Only values in memory can be extended with '@'."); + if (count < 1) + error ("Invalid number %d of repetitions.", count); + + val = allocate_repeat_value (VALUE_TYPE (arg1), count); + + read_memory (VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1), + VALUE_CONTENTS_RAW (val), + TYPE_LENGTH (VALUE_TYPE (val)) * count); + VALUE_LVAL (val) = lval_memory; + VALUE_ADDRESS (val) = VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1); + + return val; +} + +value +value_of_variable (var) + struct symbol *var; +{ + value val; + + val = read_var_value (var, (FRAME) 0); + if (val == 0) + error ("Address of symbol \"%s\" is unknown.", SYMBOL_NAME (var)); + return val; +} + +/* Given a value which is an array, return a value which is + a pointer to its first element. */ + +value +value_coerce_array (arg1) + value arg1; +{ + register struct type *type; + register value val; + + if (VALUE_LVAL (arg1) != lval_memory) + error ("Attempt to take address of value not located in memory."); + + /* Get type of elements. */ + if (TYPE_CODE (VALUE_TYPE (arg1)) == TYPE_CODE_ARRAY) + type = TYPE_TARGET_TYPE (VALUE_TYPE (arg1)); + else + /* A phony array made by value_repeat. + Its type is the type of the elements, not an array type. */ + type = VALUE_TYPE (arg1); + + /* Get the type of the result. */ + type = lookup_pointer_type (type); + val = value_from_long (builtin_type_long, + (LONGEST) (VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1))); + VALUE_TYPE (val) = type; + return val; +} + +/* Given a value which is a function, return a value which is a pointer + to it. */ + +value +value_coerce_function (arg1) + value arg1; +{ + register struct type *type; + register value val; + + if (VALUE_LVAL (arg1) != lval_memory) + error ("Attempt to take address of value not located in memory."); + + /* Get the type of the result. */ + type = lookup_pointer_type (VALUE_TYPE (arg1)); + val = value_from_long (builtin_type_long, + (LONGEST) (VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1))); + VALUE_TYPE (val) = type; + return val; +} + +/* Return a pointer value for the object for which ARG1 is the contents. */ + +value +value_addr (arg1) + value arg1; +{ + register struct type *type; + register value val; + + COERCE_REF(arg1); + /* Taking the address of an array is really a no-op + once the array is coerced to a pointer to its first element. */ + if (VALUE_REPEATED (arg1) + || TYPE_CODE (VALUE_TYPE (arg1)) == TYPE_CODE_ARRAY) + return value_coerce_array (arg1); + if (TYPE_CODE (VALUE_TYPE (arg1)) == TYPE_CODE_FUNC) + return value_coerce_function (arg1); + + if (VALUE_LVAL (arg1) != lval_memory) + error ("Attempt to take address of value not located in memory."); + + /* Get the type of the result. */ + type = lookup_pointer_type (VALUE_TYPE (arg1)); + val = value_from_long (builtin_type_long, + (LONGEST) (VALUE_ADDRESS (arg1) + VALUE_OFFSET (arg1))); + VALUE_TYPE (val) = type; + return val; +} + +/* Given a value of a pointer type, apply the C unary * operator to it. */ + +value +value_ind (arg1) + value arg1; +{ + COERCE_ARRAY (arg1); + + if (TYPE_CODE (VALUE_TYPE (arg1)) == TYPE_CODE_MEMBER) + error ("not implemented: member types in value_ind"); + + /* Allow * on an integer so we can cast it to whatever we want. + This returns an int, which seems like the most C-like thing + to do. "long long" variables are rare enough that + BUILTIN_TYPE_LONGEST would seem to be a mistake. */ + if (TYPE_CODE (VALUE_TYPE (arg1)) == TYPE_CODE_INT) + return value_at (builtin_type_int, + (CORE_ADDR) value_as_long (arg1)); + else if (TYPE_CODE (VALUE_TYPE (arg1)) == TYPE_CODE_PTR) + return value_at_lazy (TYPE_TARGET_TYPE (VALUE_TYPE (arg1)), + (CORE_ADDR) value_as_long (arg1)); + error ("Attempt to take contents of a non-pointer value."); + return 0; /* For lint -- never reached */ +} + +/* Pushing small parts of stack frames. */ + +/* Push one word (the size of object that a register holds). */ + +CORE_ADDR +push_word (sp, buffer) + CORE_ADDR sp; + REGISTER_TYPE buffer; +{ + register int len = sizeof (REGISTER_TYPE); + +#if 1 INNER_THAN 2 + sp -= len; + write_memory (sp, (char *)&buffer, len); +#else /* stack grows upward */ + write_memory (sp, (char *)&buffer, len); + sp += len; +#endif /* stack grows upward */ + + return sp; +} + +/* Push LEN bytes with data at BUFFER. */ + +CORE_ADDR +push_bytes (sp, buffer, len) + CORE_ADDR sp; + char *buffer; + int len; +{ +#if 1 INNER_THAN 2 + sp -= len; + write_memory (sp, buffer, len); +#else /* stack grows upward */ + write_memory (sp, buffer, len); + sp += len; +#endif /* stack grows upward */ + + return sp; +} + +/* Push onto the stack the specified value VALUE. */ + +CORE_ADDR +value_push (sp, arg) + register CORE_ADDR sp; + value arg; +{ + register int len = TYPE_LENGTH (VALUE_TYPE (arg)); + +#if 1 INNER_THAN 2 + sp -= len; + write_memory (sp, VALUE_CONTENTS (arg), len); +#else /* stack grows upward */ + write_memory (sp, VALUE_CONTENTS (arg), len); + sp += len; +#endif /* stack grows upward */ + + return sp; +} + +/* Perform the standard coercions that are specified + for arguments to be passed to C functions. */ + +value +value_arg_coerce (arg) + value arg; +{ + register struct type *type; + + COERCE_ENUM (arg); + + type = VALUE_TYPE (arg); + + if (TYPE_CODE (type) == TYPE_CODE_INT + && TYPE_LENGTH (type) < sizeof (int)) + return value_cast (builtin_type_int, arg); + + if (type == builtin_type_float) + return value_cast (builtin_type_double, arg); + + return arg; +} + +/* Push the value ARG, first coercing it as an argument + to a C function. */ + +CORE_ADDR +value_arg_push (sp, arg) + register CORE_ADDR sp; + value arg; +{ + return value_push (sp, value_arg_coerce (arg)); +} + +/* Determine a function's address and its return type from its value. + Calls error() if the function is not valid for calling. */ + +CORE_ADDR +find_function_addr (function, retval_type) + value function; + struct type **retval_type; +{ + register struct type *ftype = VALUE_TYPE (function); + register enum type_code code = TYPE_CODE (ftype); + struct type *value_type; + CORE_ADDR funaddr; + + /* If it's a member function, just look at the function + part of it. */ + + /* Determine address to call. */ + if (code == TYPE_CODE_FUNC || code == TYPE_CODE_METHOD) + { + funaddr = VALUE_ADDRESS (function); + value_type = TYPE_TARGET_TYPE (ftype); + } + else if (code == TYPE_CODE_PTR) + { + funaddr = value_as_long (function); + if (TYPE_CODE (TYPE_TARGET_TYPE (ftype)) == TYPE_CODE_FUNC + || TYPE_CODE (TYPE_TARGET_TYPE (ftype)) == TYPE_CODE_METHOD) + value_type = TYPE_TARGET_TYPE (TYPE_TARGET_TYPE (ftype)); + else + value_type = builtin_type_int; + } + else if (code == TYPE_CODE_INT) + { + /* Handle the case of functions lacking debugging info. + Their values are characters since their addresses are char */ + if (TYPE_LENGTH (ftype) == 1) + funaddr = value_as_long (value_addr (function)); + else + /* Handle integer used as address of a function. */ + funaddr = value_as_long (function); + + value_type = builtin_type_int; + } + else + error ("Invalid data type for function to be called."); + + *retval_type = value_type; + return funaddr; +} + +#if defined (CALL_DUMMY) +/* All this stuff with a dummy frame may seem unnecessarily complicated + (why not just save registers in GDB?). The purpose of pushing a dummy + frame which looks just like a real frame is so that if you call a + function and then hit a breakpoint (get a signal, etc), "backtrace" + will look right. Whether the backtrace needs to actually show the + stack at the time the inferior function was called is debatable, but + it certainly needs to not display garbage. So if you are contemplating + making dummy frames be different from normal frames, consider that. */ + +/* Perform a function call in the inferior. + ARGS is a vector of values of arguments (NARGS of them). + FUNCTION is a value, the function to be called. + Returns a value representing what the function returned. + May fail to return, if a breakpoint or signal is hit + during the execution of the function. */ + +value +call_function_by_hand (function, nargs, args) + value function; + int nargs; + value *args; +{ + register CORE_ADDR sp; + register int i; + CORE_ADDR start_sp; + static REGISTER_TYPE dummy[] = CALL_DUMMY; + REGISTER_TYPE dummy1[sizeof dummy / sizeof (REGISTER_TYPE)]; + CORE_ADDR old_sp; + struct type *value_type; + unsigned char struct_return; + CORE_ADDR struct_addr; + struct inferior_status inf_status; + struct cleanup *old_chain; + CORE_ADDR funaddr; + int using_gcc; + + save_inferior_status (&inf_status, 1); + old_chain = make_cleanup (restore_inferior_status, &inf_status); + + /* PUSH_DUMMY_FRAME is responsible for saving the inferior registers + (and POP_FRAME for restoring them). (At least on most machines) + they are saved on the stack in the inferior. */ + PUSH_DUMMY_FRAME; + + old_sp = sp = read_register (SP_REGNUM); + +#if 1 INNER_THAN 2 /* Stack grows down */ + sp -= sizeof dummy; + start_sp = sp; +#else /* Stack grows up */ + start_sp = sp; + sp += sizeof dummy; +#endif + + funaddr = find_function_addr (function, &value_type); + + { + struct block *b = block_for_pc (funaddr); + /* If compiled without -g, assume GCC. */ + using_gcc = b == NULL || BLOCK_GCC_COMPILED (b); + } + + /* Are we returning a value using a structure return or a normal + value return? */ + + struct_return = using_struct_return (function, funaddr, value_type, + using_gcc); + + /* Create a call sequence customized for this function + and the number of arguments for it. */ + bcopy (dummy, dummy1, sizeof dummy); + FIX_CALL_DUMMY (dummy1, start_sp, funaddr, nargs, args, + value_type, using_gcc); + +#if CALL_DUMMY_LOCATION == ON_STACK + write_memory (start_sp, (char *)dummy1, sizeof dummy); + +#else /* Not on stack. */ +#if CALL_DUMMY_LOCATION == BEFORE_TEXT_END + /* Convex Unix prohibits executing in the stack segment. */ + /* Hope there is empty room at the top of the text segment. */ + { + static checked = 0; + if (!checked) + for (start_sp = text_end - sizeof dummy; start_sp < text_end; ++start_sp) + if (read_memory_integer (start_sp, 1) != 0) + error ("text segment full -- no place to put call"); + checked = 1; + sp = old_sp; + start_sp = text_end - sizeof dummy; + write_memory (start_sp, (char *)dummy1, sizeof dummy); + } +#else /* After text_end. */ + { + int errcode; + sp = old_sp; + start_sp = text_end; + errcode = target_write_memory (start_sp, (char *)dummy1, sizeof dummy); + if (errcode != 0) + error ("Cannot write text segment -- call_function failed"); + } +#endif /* After text_end. */ +#endif /* Not on stack. */ + +#ifdef lint + sp = old_sp; /* It really is used, for some ifdef's... */ +#endif + +#ifdef STACK_ALIGN + /* If stack grows down, we must leave a hole at the top. */ + { + int len = 0; + + /* Reserve space for the return structure to be written on the + stack, if necessary */ + + if (struct_return) + len += TYPE_LENGTH (value_type); + + for (i = nargs - 1; i >= 0; i--) + len += TYPE_LENGTH (VALUE_TYPE (value_arg_coerce (args[i]))); +#ifdef CALL_DUMMY_STACK_ADJUST + len += CALL_DUMMY_STACK_ADJUST; +#endif +#if 1 INNER_THAN 2 + sp -= STACK_ALIGN (len) - len; +#else + sp += STACK_ALIGN (len) - len; +#endif + } +#endif /* STACK_ALIGN */ + + /* Reserve space for the return structure to be written on the + stack, if necessary */ + + if (struct_return) + { +#if 1 INNER_THAN 2 + sp -= TYPE_LENGTH (value_type); + struct_addr = sp; +#else + struct_addr = sp; + sp += TYPE_LENGTH (value_type); +#endif + } + +#if defined (REG_STRUCT_HAS_ADDR) + { + /* This is a machine like the sparc, where we need to pass a pointer + to the structure, not the structure itself. */ + if (REG_STRUCT_HAS_ADDR (using_gcc)) + for (i = nargs - 1; i >= 0; i--) + if (TYPE_CODE (VALUE_TYPE (args[i])) == TYPE_CODE_STRUCT) + { + CORE_ADDR addr; +#if !(1 INNER_THAN 2) + /* The stack grows up, so the address of the thing we push + is the stack pointer before we push it. */ + addr = sp; +#endif + /* Push the structure. */ + sp = value_push (sp, args[i]); +#if 1 INNER_THAN 2 + /* The stack grows down, so the address of the thing we push + is the stack pointer after we push it. */ + addr = sp; +#endif + /* The value we're going to pass is the address of the thing + we just pushed. */ + args[i] = value_from_long (builtin_type_long, (LONGEST) addr); + } + } +#endif /* REG_STRUCT_HAS_ADDR. */ + +#ifdef PUSH_ARGUMENTS + PUSH_ARGUMENTS(nargs, args, sp, struct_return, struct_addr); +#else /* !PUSH_ARGUMENTS */ + for (i = nargs - 1; i >= 0; i--) + sp = value_arg_push (sp, args[i]); +#endif /* !PUSH_ARGUMENTS */ + +#ifdef CALL_DUMMY_STACK_ADJUST +#if 1 INNER_THAN 2 + sp -= CALL_DUMMY_STACK_ADJUST; +#else + sp += CALL_DUMMY_STACK_ADJUST; +#endif +#endif /* CALL_DUMMY_STACK_ADJUST */ + + /* Store the address at which the structure is supposed to be + written. Note that this (and the code which reserved the space + above) assumes that gcc was used to compile this function. Since + it doesn't cost us anything but space and if the function is pcc + it will ignore this value, we will make that assumption. + + Also note that on some machines (like the sparc) pcc uses a + convention like gcc's. */ + + if (struct_return) + STORE_STRUCT_RETURN (struct_addr, sp); + + /* Write the stack pointer. This is here because the statements above + might fool with it. On SPARC, this write also stores the register + window into the right place in the new stack frame, which otherwise + wouldn't happen. (See write_inferior_registers in sparc-xdep.c.) */ + write_register (SP_REGNUM, sp); + + /* Figure out the value returned by the function. */ + { + char retbuf[REGISTER_BYTES]; + + /* Execute the stack dummy routine, calling FUNCTION. + When it is done, discard the empty frame + after storing the contents of all regs into retbuf. */ + run_stack_dummy (start_sp + CALL_DUMMY_START_OFFSET, retbuf); + + do_cleanups (old_chain); + + return value_being_returned (value_type, retbuf, struct_return); + } +} +#else /* no CALL_DUMMY. */ +value +call_function_by_hand (function, nargs, args) + value function; + int nargs; + value *args; +{ + error ("Cannot invoke functions on this machine."); +} +#endif /* no CALL_DUMMY. */ + +/* Create a value for a string constant: + Call the function malloc in the inferior to get space for it, + then copy the data into that space + and then return the address with type char *. + PTR points to the string constant data; LEN is number of characters. */ + +value +value_string (ptr, len) + char *ptr; + int len; +{ + register value val; + register struct symbol *sym; + value blocklen; + register char *copy = (char *) alloca (len + 1); + char *i = ptr; + register char *o = copy, *ibeg = ptr; + register int c; + + /* Copy the string into COPY, processing escapes. + We could not conveniently process them in expread + because the string there wants to be a substring of the input. */ + + while (i - ibeg < len) + { + c = *i++; + if (c == '\\') + { + c = parse_escape (&i); + if (c == -1) + continue; + } + *o++ = c; + } + *o = 0; + + /* Get the length of the string after escapes are processed. */ + + len = o - copy; + + /* Find the address of malloc in the inferior. */ + + sym = lookup_symbol ("malloc", 0, VAR_NAMESPACE, 0, NULL); + if (sym != 0) + { + if (SYMBOL_CLASS (sym) != LOC_BLOCK) + error ("\"malloc\" exists in this program but is not a function."); + val = value_of_variable (sym); + } + else + { + register int j; + for (j = 0; j < misc_function_count; j++) + if (!strcmp (misc_function_vector[j].name, "malloc")) + break; + if (j < misc_function_count) + val = value_from_long (builtin_type_long, + (LONGEST) misc_function_vector[j].address); + else + error ("String constants require the program to have a function \"malloc\"."); + } + + blocklen = value_from_long (builtin_type_int, (LONGEST) (len + 1)); + val = target_call_function (val, 1, &blocklen); + if (value_zerop (val)) + error ("No memory available for string constant."); + write_memory ((CORE_ADDR) value_as_long (val), copy, len + 1); + VALUE_TYPE (val) = lookup_pointer_type (builtin_type_char); + return val; +} + +/* Helper function used by value_struct_elt to recurse through baseclasses. + Look for a field NAME in ARG1. Adjust the address of ARG1 by OFFSET bytes, + and treat the result as having type TYPE. + If found, return value, else return NULL. */ + +static value +search_struct_field (name, arg1, offset, type) + char *name; + register value arg1; + int offset; + register struct type *type; +{ + int i; + + check_stub_type (type); + + for (i = TYPE_NFIELDS (type) - 1; i >= TYPE_N_BASECLASSES (type); i--) + { + char *t_field_name = TYPE_FIELD_NAME (type, i); + if (t_field_name && !strcmp (t_field_name, name)) + return TYPE_FIELD_STATIC (type, i) + ? value_static_field (type, name, i) + : value_primitive_field (arg1, offset, i, type); + } + + for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--) + { + value v; + /* If we are looking for baseclasses, this is what we get when we + hit them. */ + int found_baseclass = !strcmp (name, TYPE_BASECLASS_NAME (type, i)); + + if (BASETYPE_VIA_VIRTUAL (type, i)) + { + value v2; + baseclass_addr (type, i, VALUE_CONTENTS (arg1) + offset, &v2); + if (v2 == 0) + error ("virtual baseclass botch"); + if (found_baseclass) + return v2; + v = search_struct_field (name, v2, 0, TYPE_BASECLASS (type, i)); + if (v) return v; + else continue; + } + if (found_baseclass) + v = value_primitive_field (arg1, offset, i, type); + else + v = search_struct_field (name, arg1, + offset + TYPE_BASECLASS_BITPOS (type, i) / 8, + TYPE_BASECLASS (type, i)); + if (v) return v; + } + return NULL; +} + +/* Helper function used by value_struct_elt to recurse through baseclasses. + Look for a field NAME in ARG1. Adjust the address of ARG1 by OFFSET bytes, + and treat the result as having type TYPE. + If found, return value, else return NULL. */ + +static value +search_struct_method (name, arg1, args, offset, static_memfuncp, type) + char *name; + register value arg1, *args; + int offset, *static_memfuncp; + register struct type *type; +{ + int i; + + check_stub_type (type); + for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--) + { + char *t_field_name = TYPE_FN_FIELDLIST_NAME (type, i); + if (t_field_name && !strcmp (t_field_name, name)) + { + int j; + struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i); + + for (j = TYPE_FN_FIELDLIST_LENGTH (type, i) - 1; j >= 0; --j) + { + if (TYPE_FLAGS (TYPE_FN_FIELD_TYPE (f, j)) & TYPE_FLAG_STUB) + check_stub_method (type, i, j); + if (!typecmp (TYPE_FN_FIELD_STATIC_P (f, j), + TYPE_FN_FIELD_ARGS (f, j), args)) + { + if (TYPE_FN_FIELD_VIRTUAL_P (f, j)) + return (value)value_virtual_fn_field (arg1, f, j); + if (TYPE_FN_FIELD_STATIC_P (f, j) && static_memfuncp) + *static_memfuncp = 1; + return (value)value_fn_field (arg1, i, j); + } + } + } + } + + for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--) + { + value v; + + if (BASETYPE_VIA_VIRTUAL (type, i)) + { + value v2; + baseclass_addr (type, i, VALUE_CONTENTS (arg1) + offset, &v2); + if (v2 == 0) + error ("virtual baseclass botch"); + v = search_struct_method (name, v2, args, 0, + static_memfuncp, TYPE_BASECLASS (type, i)); + if (v) return v; + else continue; + } + + v = search_struct_method (name, arg1, args, + TYPE_BASECLASS_BITPOS (type, i) / 8, + static_memfuncp, TYPE_BASECLASS (type, i)); + if (v) return v; + } + return NULL; +} + +/* Given *ARGP, a value of type (pointer to a)* structure/union, + extract the component named NAME from the ultimate target structure/union + and return it as a value with its appropriate type. + ERR is used in the error message if *ARGP's type is wrong. + + C++: ARGS is a list of argument types to aid in the selection of + an appropriate method. Also, handle derived types. + + STATIC_MEMFUNCP, if non-NULL, points to a caller-supplied location + where the truthvalue of whether the function that was resolved was + a static member function or not is stored. + + ERR is an error message to be printed in case the field is not found. */ + +value +value_struct_elt (argp, args, name, static_memfuncp, err) + register value *argp, *args; + char *name; + int *static_memfuncp; + char *err; +{ + register struct type *t; + int found = 0; /* FIXME, half the time this doesn't get set */ + value arg1_as_ptr = *argp; /* FIXME, set but not used! */ + value v; + + COERCE_ARRAY (*argp); + + t = VALUE_TYPE (*argp); + + /* Follow pointers until we get to a non-pointer. */ + + while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF) + { + arg1_as_ptr = *argp; + *argp = value_ind (*argp); + COERCE_ARRAY (*argp); + t = VALUE_TYPE (*argp); + } + + if (TYPE_CODE (t) == TYPE_CODE_MEMBER) + error ("not implemented: member type in value_struct_elt"); + + if (TYPE_CODE (t) != TYPE_CODE_STRUCT + && TYPE_CODE (t) != TYPE_CODE_UNION) + error ("Attempt to extract a component of a value that is not a %s.", err); + + /* Assume it's not, unless we see that it is. */ + if (static_memfuncp) + *static_memfuncp =0; + + if (!args) + { + /* if there are no arguments ...do this... */ + + /* Try as a variable first, because if we succeed, there + is less work to be done. */ + v = search_struct_field (name, *argp, 0, t); + if (v) + return v; + + /* C++: If it was not found as a data field, then try to + return it as a pointer to a method. */ + + if (destructor_name_p (name, t)) + error ("Cannot get value of destructor"); + + v = search_struct_method (name, *argp, args, 0, static_memfuncp, t); + + if (v == 0) + { + if (TYPE_NFN_FIELDS (t)) + error ("There is no member or method named %s.", name); + else + error ("There is no member named %s.", name); + } + return v; + } + + if (destructor_name_p (name, t)) + { + if (!args[1]) + { + /* destructors are a special case. */ + return (value)value_fn_field (*argp, 0, + TYPE_FN_FIELDLIST_LENGTH (t, 0)); + } + else + { + error ("destructor should not have any argument"); + } + } + else + v = search_struct_method (name, *argp, args, 0, static_memfuncp, t); + + if (v == 0) + { + /* See if user tried to invoke data as function. If so, + hand it back. If it's not callable (i.e., a pointer to function), + gdb should give an error. */ + v = search_struct_field (name, *argp, 0, t); + } + + if (!v) + error ("Structure has no component named %s.", name); + return v; +} + +/* C++: return 1 is NAME is a legitimate name for the destructor + of type TYPE. If TYPE does not have a destructor, or + if NAME is inappropriate for TYPE, an error is signaled. */ +int +destructor_name_p (name, type) + char *name; + struct type *type; +{ + /* destructors are a special case. */ + + if (name[0] == '~') + { + char *dname = type_name_no_tag (type); + + if (! TYPE_HAS_DESTRUCTOR (type)) + error ("type `%s' does not have destructor defined", dname); + if (strcmp (dname, name+1)) + error ("name of destructor must equal name of class"); + else + return 1; + } + return 0; +} + +/* Helper function for check_field: Given TYPE, a structure/union, + return 1 if the component named NAME from the ultimate + target structure/union is defined, otherwise, return 0. */ + +static int +check_field_in (type, name) + register struct type *type; + char *name; +{ + register int i; + + for (i = TYPE_NFIELDS (type) - 1; i >= TYPE_N_BASECLASSES (type); i--) + { + char *t_field_name = TYPE_FIELD_NAME (type, i); + if (t_field_name && !strcmp (t_field_name, name)) + return 1; + } + + /* C++: If it was not found as a data field, then try to + return it as a pointer to a method. */ + + /* Destructors are a special case. */ + if (destructor_name_p (name, type)) + return 1; + + for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; --i) + { + if (!strcmp (TYPE_FN_FIELDLIST_NAME (type, i), name)) + return 1; + } + + for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--) + if (check_field_in (TYPE_BASECLASS (type, i), name)) + return 1; + + return 0; +} + + +/* C++: Given ARG1, a value of type (pointer to a)* structure/union, + return 1 if the component named NAME from the ultimate + target structure/union is defined, otherwise, return 0. */ + +int +check_field (arg1, name) + register value arg1; + char *name; +{ + register struct type *t; + + COERCE_ARRAY (arg1); + + t = VALUE_TYPE (arg1); + + /* Follow pointers until we get to a non-pointer. */ + + while (TYPE_CODE (t) == TYPE_CODE_PTR || TYPE_CODE (t) == TYPE_CODE_REF) + t = TYPE_TARGET_TYPE (t); + + if (TYPE_CODE (t) == TYPE_CODE_MEMBER) + error ("not implemented: member type in check_field"); + + if (TYPE_CODE (t) != TYPE_CODE_STRUCT + && TYPE_CODE (t) != TYPE_CODE_UNION) + error ("Internal error: `this' is not an aggregate"); + + return check_field_in (t, name); +} + +/* C++: Given an aggregate type DOMAIN, and a member name NAME, + return the address of this member as a pointer to member + type. If INTYPE is non-null, then it will be the type + of the member we are looking for. This will help us resolve + pointers to member functions. */ + +value +value_struct_elt_for_address (domain, intype, name) + struct type *domain, *intype; + char *name; +{ + register struct type *t = domain; + register int i; + value v; + + struct type *baseclass; + + if (TYPE_CODE (t) != TYPE_CODE_STRUCT + && TYPE_CODE (t) != TYPE_CODE_UNION) + error ("Internal error: non-aggregate type to value_struct_elt_for_address"); + + baseclass = t; + + while (t) + { + for (i = TYPE_NFIELDS (t) - 1; i >= TYPE_N_BASECLASSES (t); i--) + { + char *t_field_name = TYPE_FIELD_NAME (t, i); + if (t_field_name && !strcmp (t_field_name, name)) + { + if (TYPE_FIELD_STATIC (t, i)) + { + char *phys_name = TYPE_FIELD_STATIC_PHYSNAME (t, i); + struct symbol *sym = + lookup_symbol (phys_name, 0, VAR_NAMESPACE, 0, NULL); + if (! sym) error ("Internal error: could not find physical static variable named %s", phys_name); + v = value_from_long(builtin_type_long, + (CORE_ADDR)SYMBOL_BLOCK_VALUE (sym)); + VALUE_TYPE(v) = lookup_pointer_type (TYPE_FIELD_TYPE (t, i)); + return v; + } + if (TYPE_FIELD_PACKED (t, i)) + error ("pointers to bitfield members not allowed"); + + v = value_from_long (builtin_type_int, + (LONGEST) (TYPE_FIELD_BITPOS (t, i) >> 3)); + VALUE_TYPE (v) + = lookup_pointer_type (lookup_member_type (TYPE_FIELD_TYPE (t, i), baseclass)); + return v; + } + } + + if (TYPE_N_BASECLASSES (t) == 0) + break; + + t = TYPE_BASECLASS (t, 0); + } + + /* C++: If it was not found as a data field, then try to + return it as a pointer to a method. */ + t = baseclass; + + /* Destructors are a special case. */ + if (destructor_name_p (name, t)) + { + error ("pointers to destructors not implemented yet"); + } + + /* Perform all necessary dereferencing. */ + while (intype && TYPE_CODE (intype) == TYPE_CODE_PTR) + intype = TYPE_TARGET_TYPE (intype); + + while (t) + { + for (i = TYPE_NFN_FIELDS (t) - 1; i >= 0; --i) + { + if (!strcmp (TYPE_FN_FIELDLIST_NAME (t, i), name)) + { + int j = TYPE_FN_FIELDLIST_LENGTH (t, i); + struct fn_field *f = TYPE_FN_FIELDLIST1 (t, i); + + if (intype == 0 && j > 1) + error ("non-unique member `%s' requires type instantiation", name); + if (intype) + { + while (j--) + if (TYPE_FN_FIELD_TYPE (f, j) == intype) + break; + if (j < 0) + error ("no member function matches that type instantiation"); + } + else + j = 0; + + if (TYPE_FN_FIELD_VIRTUAL_P (f, j)) + { + v = value_from_long (builtin_type_long, + (LONGEST) TYPE_FN_FIELD_VOFFSET (f, j)); + } + else + { + struct symbol *s = lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j), + 0, VAR_NAMESPACE, 0, NULL); + v = locate_var_value (s, 0); + } + VALUE_TYPE (v) = lookup_pointer_type (lookup_member_type (TYPE_FN_FIELD_TYPE (f, j), baseclass)); + return v; + } + } + + if (TYPE_N_BASECLASSES (t) == 0) + break; + + t = TYPE_BASECLASS (t, 0); + } + return 0; +} + +/* Compare two argument lists and return the position in which they differ, + or zero if equal. + + STATICP is nonzero if the T1 argument list came from a + static member function. + + For non-static member functions, we ignore the first argument, + which is the type of the instance variable. This is because we want + to handle calls with objects from derived classes. This is not + entirely correct: we should actually check to make sure that a + requested operation is type secure, shouldn't we? FIXME. */ + +int +typecmp (staticp, t1, t2) + int staticp; + struct type *t1[]; + value t2[]; +{ + int i; + + if (staticp && t1 == 0) + return t2[1] != 0; + if (t1 == 0) + return 1; + if (t1[0]->code == TYPE_CODE_VOID) return 0; + if (t1[!staticp] == 0) return 0; + for (i = !staticp; t1[i] && t1[i]->code != TYPE_CODE_VOID; i++) + { + if (! t2[i] + || t1[i]->code != t2[i]->type->code +/* Too pessimistic: || t1[i]->target_type != t2[i]->type->target_type */ + ) + return i+1; + } + if (!t1[i]) return 0; + return t2[i] ? i+1 : 0; +} + +/* C++: return the value of the class instance variable, if one exists. + Flag COMPLAIN signals an error if the request is made in an + inappropriate context. */ +value +value_of_this (complain) + int complain; +{ + extern FRAME selected_frame; + struct symbol *func, *sym; + struct block *b; + int i; + static const char funny_this[] = "this"; + value this; + + + if (selected_frame == 0) + if (complain) + error ("no frame selected"); + else return 0; + + func = get_frame_function (selected_frame); + if (!func) + { + if (complain) + error ("no `this' in nameless context"); + else return 0; + } + + b = SYMBOL_BLOCK_VALUE (func); + i = BLOCK_NSYMS (b); + if (i <= 0) + if (complain) + error ("no args, no `this'"); + else return 0; + + /* Calling lookup_block_symbol is necessary to get the LOC_REGISTER + symbol instead of the LOC_ARG one (if both exist). */ + sym = lookup_block_symbol (b, funny_this, VAR_NAMESPACE); + if (sym == NULL) + { + if (complain) + error ("current stack frame not in method"); + else + return NULL; + } + + this = read_var_value (sym, selected_frame); + if (this == 0 && complain) + error ("`this' argument at unknown address"); + return this; +} |