/* Find a variable's value in memory, for GDB, the GNU debugger.
- Copyright (C) 1986, 1987 Free Software Foundation, Inc.
+ Copyright 1986, 1987, 1989, 1991 Free Software Foundation, Inc.
-GDB is distributed in the hope that it will be useful, but WITHOUT ANY
-WARRANTY. No author or distributor accepts responsibility to anyone
-for the consequences of using it or for whether it serves any
-particular purpose or works at all, unless he says so in writing.
-Refer to the GDB General Public License for full details.
+This file is part of GDB.
-Everyone is granted permission to copy, modify and redistribute GDB,
-but only under the conditions described in the GDB General Public
-License. A copy of this license is supposed to have been given to you
-along with GDB so you can know your rights and responsibilities. It
-should be in a file named COPYING. Among other things, the copyright
-notice and this notice must be preserved on all copies.
+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 2 of the License, or
+(at your option) any later version.
-In other words, go ahead and share GDB, but don't try to stop
-anyone else from sharing it farther. Help stamp out software hoarding!
-*/
+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, write to the Free Software
+Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
#include "defs.h"
-#include "param.h"
#include "symtab.h"
+#include "gdbtypes.h"
#include "frame.h"
#include "value.h"
+#include "gdbcore.h"
+#include "inferior.h"
+#include "target.h"
-CORE_ADDR read_register ();
+#if !defined (GET_SAVED_REGISTER)
/* Return the address in which frame FRAME's value of register REGNUM
has been saved in memory. Or return zero if it has not been saved.
register FRAME frame1 = 0;
register CORE_ADDR addr = 0;
+ if (frame == 0) /* No regs saved if want current frame */
+ return 0;
+
#ifdef HAVE_REGISTER_WINDOWS
/* We assume that a register in a register window will only be saved
- in one place (since the name changes and dissapears as you go
+ in one place (since the name changes and/or disappears as you go
towards inner frames), so we only call get_frame_saved_regs on
the current frame. This is directly in contradiction to the
usage below, which assumes that registers used in a frame must be
always returns the registers saved within a frame, within the
context (register namespace) of that frame. */
+ /* However, note that we don't want this to return anything if
+ nothing is saved (if there's a frame inside of this one). Also,
+ callers to this routine asking for the stack pointer want the
+ stack pointer saved for *this* frame; this is returned from the
+ next frame. */
+
+
if (REGISTER_IN_WINDOW_P(regnum))
{
- fi = get_frame_info (frame);
+ frame1 = get_next_frame (frame);
+ if (!frame1) return 0; /* Registers of this frame are
+ active. */
+
+ /* Get the SP from the next frame in; it will be this
+ current frame. */
+ if (regnum != SP_REGNUM)
+ frame1 = frame;
+
+ fi = get_frame_info (frame1);
get_frame_saved_regs (fi, &saved_regs);
- return (saved_regs.regs[regnum] ?
- saved_regs.regs[regnum] : 0);
+ return saved_regs.regs[regnum]; /* ... which might be zero */
}
#endif /* HAVE_REGISTER_WINDOWS */
return addr;
}
-/* Copy the bytes of register REGNUM, relative to the current stack frame,
- into our memory at MYADDR.
- The number of bytes copied is REGISTER_RAW_SIZE (REGNUM). */
+/* Find register number REGNUM relative to FRAME and put its
+ (raw) contents in *RAW_BUFFER. Set *OPTIMIZED if the variable
+ was optimized out (and thus can't be fetched). Set *LVAL to
+ lval_memory, lval_register, or not_lval, depending on whether the
+ value was fetched from memory, from a register, or in a strange
+ and non-modifiable way (e.g. a frame pointer which was calculated
+ rather than fetched). Set *ADDRP to the address, either in memory
+ on as a REGISTER_BYTE offset into the registers array.
+
+ Note that this implementation never sets *LVAL to not_lval. But
+ it can be replaced by defining GET_SAVED_REGISTER and supplying
+ your own.
+ The argument RAW_BUFFER must point to aligned memory. */
void
-read_relative_register_raw_bytes (regnum, myaddr)
+get_saved_register (raw_buffer, optimized, addrp, frame, regnum, lval)
+ char *raw_buffer;
+ int *optimized;
+ CORE_ADDR *addrp;
+ FRAME frame;
int regnum;
- char *myaddr;
+ enum lval_type *lval;
{
- register CORE_ADDR addr;
-
- if (regnum == FP_REGNUM)
+ CORE_ADDR addr;
+ /* Normal systems don't optimize out things with register numbers. */
+ if (optimized != NULL)
+ *optimized = 0;
+ addr = find_saved_register (frame, regnum);
+ if (addr != 0)
+ {
+ if (lval != NULL)
+ *lval = lval_memory;
+ if (regnum == SP_REGNUM)
+ {
+ if (raw_buffer != NULL)
+ *(CORE_ADDR *)raw_buffer = addr;
+ if (addrp != NULL)
+ *addrp = 0;
+ return;
+ }
+ if (raw_buffer != NULL)
+ read_memory (addr, raw_buffer, REGISTER_RAW_SIZE (regnum));
+ }
+ else
{
- bcopy (&FRAME_FP(selected_frame), myaddr, sizeof (CORE_ADDR));
- return;
+ if (lval != NULL)
+ *lval = lval_register;
+ addr = REGISTER_BYTE (regnum);
+ if (raw_buffer != NULL)
+ read_register_gen (regnum, raw_buffer);
}
+ if (addrp != NULL)
+ *addrp = addr;
+}
+#endif /* GET_SAVED_REGISTER. */
+
+/* Copy the bytes of register REGNUM, relative to the current stack frame,
+ into our memory at MYADDR, in target byte order.
+ The number of bytes copied is REGISTER_RAW_SIZE (REGNUM).
- addr = find_saved_register (selected_frame, regnum);
+ Returns 1 if could not be read, 0 if could. */
- if (addr)
+int
+read_relative_register_raw_bytes (regnum, myaddr)
+ int regnum;
+ char *myaddr;
+{
+ int optim;
+ if (regnum == FP_REGNUM && selected_frame)
{
- if (regnum == SP_REGNUM)
- {
- CORE_ADDR buffer = addr;
- bcopy (&buffer, myaddr, sizeof (CORE_ADDR));
- }
- else
- read_memory (addr, myaddr, REGISTER_RAW_SIZE (regnum));
- return;
+ (void) memcpy (myaddr, &FRAME_FP(selected_frame),
+ REGISTER_RAW_SIZE(FP_REGNUM));
+ SWAP_TARGET_AND_HOST (myaddr, REGISTER_RAW_SIZE(FP_REGNUM)); /* in target order */
+ return 0;
}
- read_register_bytes (REGISTER_BYTE (regnum),
- myaddr, REGISTER_RAW_SIZE (regnum));
+
+ get_saved_register (myaddr, &optim, (CORE_ADDR *) NULL, selected_frame,
+ regnum, (enum lval_type *)NULL);
+ return optim;
}
/* Return a `value' with the contents of register REGNUM
value_of_register (regnum)
int regnum;
{
- register CORE_ADDR addr;
+ CORE_ADDR addr;
+ int optim;
register value val;
char raw_buffer[MAX_REGISTER_RAW_SIZE];
char virtual_buffer[MAX_REGISTER_VIRTUAL_SIZE];
+ enum lval_type lval;
- if (! (have_inferior_p () || have_core_file_p ()))
- error ("Can't get value of register without inferior or core file");
-
- addr = find_saved_register (selected_frame, regnum);
- if (addr)
- {
- if (regnum == SP_REGNUM)
- return value_from_long (builtin_type_int, (LONGEST) addr);
- read_memory (addr, raw_buffer, REGISTER_RAW_SIZE (regnum));
- }
- else
- read_register_bytes (REGISTER_BYTE (regnum), raw_buffer,
- REGISTER_RAW_SIZE (regnum));
+ get_saved_register (raw_buffer, &optim, &addr,
+ selected_frame, regnum, &lval);
- REGISTER_CONVERT_TO_VIRTUAL (regnum, raw_buffer, virtual_buffer);
+ target_convert_to_virtual (regnum, raw_buffer, virtual_buffer);
val = allocate_value (REGISTER_VIRTUAL_TYPE (regnum));
- bcopy (virtual_buffer, VALUE_CONTENTS (val), REGISTER_VIRTUAL_SIZE (regnum));
- VALUE_LVAL (val) = addr ? lval_memory : lval_register;
- VALUE_ADDRESS (val) = addr ? addr : REGISTER_BYTE (regnum);
+ (void) memcpy (VALUE_CONTENTS_RAW (val), virtual_buffer,
+ REGISTER_VIRTUAL_SIZE (regnum));
+ VALUE_LVAL (val) = lval;
+ VALUE_ADDRESS (val) = addr;
VALUE_REGNO (val) = regnum;
+ VALUE_OPTIMIZED_OUT (val) = optim;
return val;
}
\f
/* Low level examining and depositing of registers.
- Note that you must call `fetch_registers' once
- before examining or depositing any registers. */
+ The caller is responsible for making
+ sure that the inferior is stopped before calling the fetching routines,
+ or it will get garbage. (a change from GDB version 3, in which
+ the caller got the value from the last stop). */
+
+/* Contents of the registers in target byte order.
+ We allocate some extra slop since we do a lot of bcopy's around `registers',
+ and failing-soft is better than failing hard. */
+char registers[REGISTER_BYTES + /* SLOP */ 256];
-char registers[REGISTER_BYTES];
+/* Nonzero if that register has been fetched. */
+char register_valid[NUM_REGS];
+
+/* Indicate that registers may have changed, so invalidate the cache. */
+void
+registers_changed ()
+{
+ int i;
+ for (i = 0; i < NUM_REGS; i++)
+ register_valid[i] = 0;
+}
+
+/* Indicate that all registers have been fetched, so mark them all valid. */
+void
+registers_fetched ()
+{
+ int i;
+ for (i = 0; i < NUM_REGS; i++)
+ register_valid[i] = 1;
+}
/* Copy LEN bytes of consecutive data from registers
starting with the REGBYTE'th byte of register data
char *myaddr;
int len;
{
- bcopy (®isters[regbyte], myaddr, len);
+ /* Fetch all registers. */
+ int i;
+ for (i = 0; i < NUM_REGS; i++)
+ if (!register_valid[i])
+ {
+ target_fetch_registers (-1);
+ break;
+ }
+ if (myaddr != NULL)
+ (void) memcpy (myaddr, ®isters[regbyte], len);
+}
+
+/* Read register REGNO into memory at MYADDR, which must be large enough
+ for REGISTER_RAW_BYTES (REGNO). Target byte-order.
+ If the register is known to be the size of a CORE_ADDR or smaller,
+ read_register can be used instead. */
+void
+read_register_gen (regno, myaddr)
+ int regno;
+ char *myaddr;
+{
+ if (!register_valid[regno])
+ target_fetch_registers (regno);
+ (void) memcpy (myaddr, ®isters[REGISTER_BYTE (regno)],
+ REGISTER_RAW_SIZE (regno));
}
/* Copy LEN bytes of consecutive data from memory at MYADDR
char *myaddr;
int len;
{
- bcopy (myaddr, ®isters[regbyte], len);
- if (have_inferior_p ())
- store_inferior_registers (-1);
+ /* Make sure the entire registers array is valid. */
+ read_register_bytes (0, (char *)NULL, REGISTER_BYTES);
+ (void) memcpy (®isters[regbyte], myaddr, len);
+ target_store_registers (-1);
}
-/* Return the contents of register REGNO,
- regarding it as an integer. */
+/* Return the contents of register REGNO, regarding it as an integer. */
+/* FIXME, this loses when the REGISTER_VIRTUAL (REGNO) is true. Also,
+ why is the return type CORE_ADDR rather than some integer type? */
CORE_ADDR
read_register (regno)
int regno;
{
- /* This loses when REGISTER_RAW_SIZE (regno) != sizeof (int) */
- return *(int *) ®isters[REGISTER_BYTE (regno)];
+ REGISTER_TYPE reg;
+
+ if (!register_valid[regno])
+ target_fetch_registers (regno);
+ memcpy (®, ®isters[REGISTER_BYTE (regno)], sizeof (REGISTER_TYPE));
+ SWAP_TARGET_AND_HOST (®, sizeof (REGISTER_TYPE));
+ return reg;
}
+/* Registers we shouldn't try to store. */
+#if !defined (CANNOT_STORE_REGISTER)
+#define CANNOT_STORE_REGISTER(regno) 0
+#endif
+
/* Store VALUE in the register number REGNO, regarded as an integer. */
+/* FIXME, this loses when REGISTER_VIRTUAL (REGNO) is true. Also,
+ shouldn't the val arg be a LONGEST or something? */
void
write_register (regno, val)
int regno, val;
{
- /* This loses when REGISTER_RAW_SIZE (regno) != sizeof (int) */
-#if defined(sun4)
- /* This is a no-op on a Sun 4. */
- if (regno == 0)
+ REGISTER_TYPE reg;
+
+ /* On the sparc, writing %g0 is a no-op, so we don't even want to change
+ the registers array if something writes to this register. */
+ if (CANNOT_STORE_REGISTER (regno))
return;
-#endif
- *(int *) ®isters[REGISTER_BYTE (regno)] = val;
+ reg = val;
+ SWAP_TARGET_AND_HOST (®, sizeof (REGISTER_TYPE));
+
+ target_prepare_to_store ();
+
+ register_valid [regno] = 1;
+ memcpy (®isters[REGISTER_BYTE (regno)], ®, sizeof (REGISTER_TYPE));
- if (have_inferior_p ())
- store_inferior_registers (regno);
+ target_store_registers (regno);
}
/* Record that register REGNO contains VAL.
int regno;
char *val;
{
- bcopy (val, ®isters[REGISTER_BYTE (regno)], REGISTER_RAW_SIZE (regno));
+ register_valid[regno] = 1;
+ (void) memcpy (®isters[REGISTER_BYTE (regno)], val,
+ REGISTER_RAW_SIZE (regno));
}
\f
/* Given a struct symbol for a variable,
- and a stack frame address, read the value of the variable
- and return a (pointer to a) struct value containing the value. */
+ and a stack frame id, read the value of the variable
+ and return a (pointer to a) struct value containing the value.
+ If the variable cannot be found, return a zero pointer.
+ If FRAME is NULL, use the selected_frame. */
value
read_var_value (var, frame)
FRAME frame;
{
register value v;
-
struct frame_info *fi;
-
struct type *type = SYMBOL_TYPE (var);
- register CORE_ADDR addr = 0;
- int val = SYMBOL_VALUE (var);
+ CORE_ADDR addr;
register int len;
v = allocate_value (type);
switch (SYMBOL_CLASS (var))
{
case LOC_CONST:
- case LOC_LABEL:
- bcopy (&val, VALUE_CONTENTS (v), len);
+ (void) memcpy (VALUE_CONTENTS_RAW (v), &SYMBOL_VALUE (var), len);
+ SWAP_TARGET_AND_HOST (VALUE_CONTENTS_RAW (v), len);
VALUE_LVAL (v) = not_lval;
return v;
- case LOC_CONST_BYTES:
- bcopy (val, VALUE_CONTENTS (v), len);
+ case LOC_LABEL:
+ addr = SYMBOL_VALUE_ADDRESS (var);
+ (void) memcpy (VALUE_CONTENTS_RAW (v), &addr, len);
+ SWAP_TARGET_AND_HOST (VALUE_CONTENTS_RAW (v), len);
VALUE_LVAL (v) = not_lval;
return v;
+ case LOC_CONST_BYTES:
+ {
+ char *bytes_addr;
+ bytes_addr = SYMBOL_VALUE_BYTES (var);
+ (void) memcpy (VALUE_CONTENTS_RAW (v), bytes_addr, len);
+ VALUE_LVAL (v) = not_lval;
+ return v;
+ }
+
case LOC_STATIC:
- addr = val;
+ addr = SYMBOL_VALUE_ADDRESS (var);
break;
case LOC_ARG:
- fi = get_frame_info (frame);
- addr = val + FRAME_ARGS_ADDRESS (fi);
+ if (SYMBOL_BASEREG_VALID (var))
+ {
+ addr = FRAME_GET_BASEREG_VALUE (frame, SYMBOL_BASEREG (var));
+ }
+ else
+ {
+ fi = get_frame_info (frame);
+ if (fi == NULL)
+ return 0;
+ addr = FRAME_ARGS_ADDRESS (fi);
+ }
+ if (!addr)
+ {
+ return 0;
+ }
+ addr += SYMBOL_VALUE (var);
break;
-
+
+ case LOC_REF_ARG:
+ if (SYMBOL_BASEREG_VALID (var))
+ {
+ addr = FRAME_GET_BASEREG_VALUE (frame, SYMBOL_BASEREG (var));
+ }
+ else
+ {
+ fi = get_frame_info (frame);
+ if (fi == NULL)
+ return 0;
+ addr = FRAME_ARGS_ADDRESS (fi);
+ }
+ if (!addr)
+ {
+ return 0;
+ }
+ addr += SYMBOL_VALUE (var);
+ read_memory (addr, (char *) &addr, sizeof (CORE_ADDR));
+ break;
+
case LOC_LOCAL:
- fi = get_frame_info (frame);
- addr = val + FRAME_LOCALS_ADDRESS (fi);
+ case LOC_LOCAL_ARG:
+ if (SYMBOL_BASEREG_VALID (var))
+ {
+ addr = FRAME_GET_BASEREG_VALUE (frame, SYMBOL_BASEREG (var));
+ }
+ else
+ {
+ fi = get_frame_info (frame);
+ if (fi == NULL)
+ return 0;
+ addr = FRAME_LOCALS_ADDRESS (fi);
+ }
+ addr += SYMBOL_VALUE (var);
break;
case LOC_TYPEDEF:
error ("Cannot look up value of a typedef");
+ break;
case LOC_BLOCK:
VALUE_ADDRESS (v) = BLOCK_START (SYMBOL_BLOCK_VALUE (var));
case LOC_REGISTER:
case LOC_REGPARM:
- v = value_from_register (type, val, frame);
- return v;
+ {
+ struct block *b;
+
+ if (frame == NULL)
+ return 0;
+ b = get_frame_block (frame);
+
+ v = value_from_register (type, SYMBOL_VALUE (var), frame);
+
+ /* Nonzero if a struct which is located in a register or a LOC_ARG
+ really contains
+ the address of the struct, not the struct itself. GCC_P is nonzero
+ if the function was compiled with GCC. */
+#if !defined (REG_STRUCT_HAS_ADDR)
+#define REG_STRUCT_HAS_ADDR(gcc_p) 0
+#endif
+
+ if (REG_STRUCT_HAS_ADDR (BLOCK_GCC_COMPILED (b))
+ && ( (TYPE_CODE (type) == TYPE_CODE_STRUCT)
+ || (TYPE_CODE (type) == TYPE_CODE_UNION)))
+ addr = *(CORE_ADDR *)VALUE_CONTENTS (v);
+ else
+ return v;
+ }
+ break;
+
+ default:
+ error ("Cannot look up value of a botched symbol.");
+ break;
}
- read_memory (addr, VALUE_CONTENTS (v), len);
VALUE_ADDRESS (v) = addr;
+ VALUE_LAZY (v) = 1;
return v;
}
char raw_buffer [MAX_REGISTER_RAW_SIZE];
char virtual_buffer[MAX_REGISTER_VIRTUAL_SIZE];
CORE_ADDR addr;
+ int optim;
value v = allocate_value (type);
int len = TYPE_LENGTH (type);
char *value_bytes = 0;
int value_bytes_copied = 0;
int num_storage_locs;
+ enum lval_type lval;
VALUE_REGNO (v) = regnum;
int mem_stor = 0, reg_stor = 0;
int mem_tracking = 1;
CORE_ADDR last_addr = 0;
+ CORE_ADDR first_addr;
value_bytes = (char *) alloca (len + MAX_REGISTER_RAW_SIZE);
(value_bytes_copied += REGISTER_RAW_SIZE (local_regnum),
++local_regnum))
{
- int register_index = local_regnum - regnum;
- addr = find_saved_register (frame, local_regnum);
- if (addr == 0)
- {
- read_register_bytes (REGISTER_BYTE (local_regnum),
- value_bytes + value_bytes_copied,
- REGISTER_RAW_SIZE (local_regnum));
- reg_stor++;
- }
+ get_saved_register (value_bytes + value_bytes_copied,
+ &optim,
+ &addr,
+ frame,
+ local_regnum,
+ &lval);
+ if (lval == lval_register)
+ reg_stor++;
else
{
- read_memory (addr, value_bytes + value_bytes_copied,
- REGISTER_RAW_SIZE (local_regnum));
mem_stor++;
+
+ if (regnum == local_regnum)
+ first_addr = addr;
+
mem_tracking =
(mem_tracking
&& (regnum == local_regnum
else if (mem_stor)
{
VALUE_LVAL (v) = lval_memory;
- VALUE_ADDRESS (v) = find_saved_register (frame, regnum);
+ VALUE_ADDRESS (v) = first_addr;
}
else if (reg_stor)
{
VALUE_LVAL (v) = lval_register;
- VALUE_ADDRESS (v) = REGISTER_BYTE (regnum);
+ VALUE_ADDRESS (v) = first_addr;
}
else
fatal ("value_from_register: Value not stored anywhere!");
-
+
+ VALUE_OPTIMIZED_OUT (v) = optim;
+
/* Any structure stored in more than one register will always be
- an inegral number of registers. Otherwise, you'd need to do
+ an integral number of registers. Otherwise, you'd need to do
some fiddling with the last register copied here for little
endian machines. */
/* Copy into the contents section of the value. */
- bcopy (value_bytes, VALUE_CONTENTS (v), len);
+ (void) memcpy (VALUE_CONTENTS_RAW (v), value_bytes, len);
return v;
}
/* Data is completely contained within a single register. Locate the
register's contents in a real register or in core;
read the data in raw format. */
-
- addr = find_saved_register (frame, regnum);
- if (addr == 0)
- {
- /* Value is really in a register. */
-
- VALUE_LVAL (v) = lval_register;
- VALUE_ADDRESS (v) = REGISTER_BYTE (regnum);
-
- read_register_bytes (REGISTER_BYTE (regnum),
- raw_buffer, REGISTER_RAW_SIZE (regnum));
- }
- else
- {
- /* Value was in a register that has been saved in memory. */
-
- read_memory (addr, raw_buffer, REGISTER_RAW_SIZE (regnum));
- VALUE_LVAL (v) = lval_memory;
- VALUE_ADDRESS (v) = addr;
- }
+
+ get_saved_register (raw_buffer, &optim, &addr, frame, regnum, &lval);
+ VALUE_OPTIMIZED_OUT (v) = optim;
+ VALUE_LVAL (v) = lval;
+ VALUE_ADDRESS (v) = addr;
/* Convert the raw contents to virtual contents.
(Just copy them if the formats are the same.) */
- REGISTER_CONVERT_TO_VIRTUAL (regnum, raw_buffer, virtual_buffer);
+ target_convert_to_virtual (regnum, raw_buffer, virtual_buffer);
if (REGISTER_CONVERTIBLE (regnum))
{
with raw type `extended' and virtual type `double'.
Fetch it as a `double' and then convert to `float'. */
v = allocate_value (REGISTER_VIRTUAL_TYPE (regnum));
- bcopy (virtual_buffer, VALUE_CONTENTS (v), len);
+ (void) memcpy (VALUE_CONTENTS_RAW (v), virtual_buffer, len);
v = value_cast (type, v);
}
else
- bcopy (virtual_buffer, VALUE_CONTENTS (v), len);
+ (void) memcpy (VALUE_CONTENTS_RAW (v), virtual_buffer, len);
}
else
{
/* Raw and virtual formats are the same for this register. */
-
-#ifdef BYTES_BIG_ENDIAN
+
+#if TARGET_BYTE_ORDER == BIG_ENDIAN
if (len < REGISTER_RAW_SIZE (regnum))
{
- /* Big-endian, and we want less than full size. */
+ /* Big-endian, and we want less than full size. */
VALUE_OFFSET (v) = REGISTER_RAW_SIZE (regnum) - len;
}
#endif
-
- bcopy (virtual_buffer + VALUE_OFFSET (v),
- VALUE_CONTENTS (v), len);
+
+ (void) memcpy (VALUE_CONTENTS_RAW (v), virtual_buffer + VALUE_OFFSET (v),
+ len);
}
return v;
}
\f
-/* Given a struct symbol for a variable,
- and a stack frame address,
- return a (pointer to a) struct value containing the variable's address. */
+/* Given a struct symbol for a variable or function,
+ and a stack frame id,
+ return a (pointer to a) struct value containing the properly typed
+ address. */
value
locate_var_value (var, frame)
register struct symbol *var;
FRAME frame;
{
- register CORE_ADDR addr = 0;
- int val = SYMBOL_VALUE (var);
- struct frame_info *fi;
+ CORE_ADDR addr = 0;
struct type *type = SYMBOL_TYPE (var);
+ value lazy_value;
- if (frame == 0) frame = selected_frame;
+ /* Evaluate it first; if the result is a memory address, we're fine.
+ Lazy evaluation pays off here. */
- switch (SYMBOL_CLASS (var))
+ lazy_value = read_var_value (var, frame);
+ if (lazy_value == 0)
+ error ("Address of \"%s\" is unknown.", SYMBOL_NAME (var));
+
+ if (VALUE_LAZY (lazy_value)
+ || TYPE_CODE (type) == TYPE_CODE_FUNC)
{
- case LOC_CONST:
- case LOC_CONST_BYTES:
- error ("Address requested for identifier \"%s\" which is a constant.",
- SYMBOL_NAME (var));
+ addr = VALUE_ADDRESS (lazy_value);
+ return value_from_longest (lookup_pointer_type (type), (LONGEST) addr);
+ }
- case LOC_REGISTER:
- case LOC_REGPARM:
- addr = find_saved_register (frame, val);
- if (addr != 0)
- {
- int len = TYPE_LENGTH (type);
-#ifdef BYTES_BIG_ENDIAN
- if (len < REGISTER_RAW_SIZE (val))
- /* Big-endian, and we want less than full size. */
- addr += REGISTER_RAW_SIZE (val) - len;
-#endif
- break;
- }
+ /* Not a memory address; check what the problem was. */
+ switch (VALUE_LVAL (lazy_value))
+ {
+ case lval_register:
+ case lval_reg_frame_relative:
error ("Address requested for identifier \"%s\" which is in a register.",
SYMBOL_NAME (var));
-
- case LOC_STATIC:
- case LOC_LABEL:
- addr = val;
- break;
-
- case LOC_ARG:
- fi = get_frame_info (frame);
- addr = val + FRAME_ARGS_ADDRESS (fi);
break;
- case LOC_LOCAL:
- fi = get_frame_info (frame);
- addr = val + FRAME_LOCALS_ADDRESS (fi);
- break;
-
- case LOC_TYPEDEF:
- error ("Address requested for identifier \"%s\" which is a typedef.",
+ default:
+ error ("Can't take address of \"%s\" which isn't an lvalue.",
SYMBOL_NAME (var));
-
- case LOC_BLOCK:
- addr = BLOCK_START (SYMBOL_BLOCK_VALUE (var));
break;
}
-
- return value_cast (lookup_pointer_type (type),
- value_from_long (builtin_type_long, (LONGEST) addr));
+ return 0; /* For lint -- never reached */
}
-