/* Find a variable's value in memory, for GDB, the GNU debugger.
- Copyright (C) 1986, 1987 Free Software Foundation, Inc.
+ Copyright 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995,
+ 1996, 1997, 1998, 1999, 2000, 2001
+ 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., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA. */
#include "defs.h"
-#include "initialize.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"
+#include "gdb_string.h"
+#include "gdb_assert.h"
+#include "floatformat.h"
+#include "symfile.h" /* for overlay functions */
+#include "regcache.h"
+#include "builtin-regs.h"
+
+/* Basic byte-swapping routines. GDB has needed these for a long time...
+ All extract a target-format integer at ADDR which is LEN bytes long. */
+
+#if TARGET_CHAR_BIT != 8 || HOST_CHAR_BIT != 8
+ /* 8 bit characters are a pretty safe assumption these days, so we
+ assume it throughout all these swapping routines. If we had to deal with
+ 9 bit characters, we would need to make len be in bits and would have
+ to re-write these routines... */
+you lose
+#endif
-CORE_ADDR read_register ();
+LONGEST
+extract_signed_integer (const void *addr, int len)
+{
+ LONGEST retval;
+ const unsigned char *p;
+ const unsigned char *startaddr = addr;
+ const unsigned char *endaddr = startaddr + len;
+
+ if (len > (int) sizeof (LONGEST))
+ error ("\
+That operation is not available on integers of more than %d bytes.",
+ (int) sizeof (LONGEST));
+
+ /* Start at the most significant end of the integer, and work towards
+ the least significant. */
+ if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
+ {
+ p = startaddr;
+ /* Do the sign extension once at the start. */
+ retval = ((LONGEST) * p ^ 0x80) - 0x80;
+ for (++p; p < endaddr; ++p)
+ retval = (retval << 8) | *p;
+ }
+ else
+ {
+ p = endaddr - 1;
+ /* Do the sign extension once at the start. */
+ retval = ((LONGEST) * p ^ 0x80) - 0x80;
+ for (--p; p >= startaddr; --p)
+ retval = (retval << 8) | *p;
+ }
+ return retval;
+}
-START_FILE
-\f
-/* 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.
- If REGNUM specifies the SP, the value we return is actually
- the SP value, not an address where it was saved. */
-
-static CORE_ADDR
-find_saved_register (frame, regnum)
- FRAME frame;
- int regnum;
+ULONGEST
+extract_unsigned_integer (const void *addr, int len)
{
- struct frame_info fi;
- struct frame_saved_regs saved_regs;
+ ULONGEST retval;
+ const unsigned char *p;
+ const unsigned char *startaddr = addr;
+ const unsigned char *endaddr = startaddr + len;
+
+ if (len > (int) sizeof (ULONGEST))
+ error ("\
+That operation is not available on integers of more than %d bytes.",
+ (int) sizeof (ULONGEST));
+
+ /* Start at the most significant end of the integer, and work towards
+ the least significant. */
+ retval = 0;
+ if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
+ {
+ for (p = startaddr; p < endaddr; ++p)
+ retval = (retval << 8) | *p;
+ }
+ else
+ {
+ for (p = endaddr - 1; p >= startaddr; --p)
+ retval = (retval << 8) | *p;
+ }
+ return retval;
+}
+
+/* Sometimes a long long unsigned integer can be extracted as a
+ LONGEST value. This is done so that we can print these values
+ better. If this integer can be converted to a LONGEST, this
+ function returns 1 and sets *PVAL. Otherwise it returns 0. */
- register FRAME frame1 = 0;
- register CORE_ADDR addr = 0;
+int
+extract_long_unsigned_integer (void *addr, int orig_len, LONGEST *pval)
+{
+ char *p, *first_addr;
+ int len;
- while (1)
+ len = orig_len;
+ if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
{
- QUIT;
- fi = get_prev_frame_info (frame1);
- if (fi.frame == 0 || fi.frame == frame)
- break;
- get_frame_saved_regs (&fi, &saved_regs);
- if (saved_regs.regs[regnum])
- addr = saved_regs.regs[regnum];
- frame1 = fi.frame;
+ for (p = (char *) addr;
+ len > (int) sizeof (LONGEST) && p < (char *) addr + orig_len;
+ p++)
+ {
+ if (*p == 0)
+ len--;
+ else
+ break;
+ }
+ first_addr = p;
+ }
+ else
+ {
+ first_addr = (char *) addr;
+ for (p = (char *) addr + orig_len - 1;
+ len > (int) sizeof (LONGEST) && p >= (char *) addr;
+ p--)
+ {
+ if (*p == 0)
+ len--;
+ else
+ break;
+ }
+ }
+
+ if (len <= (int) sizeof (LONGEST))
+ {
+ *pval = (LONGEST) extract_unsigned_integer (first_addr,
+ sizeof (LONGEST));
+ return 1;
}
- return addr;
+ return 0;
+}
+
+
+/* Treat the LEN bytes at ADDR as a target-format address, and return
+ that address. ADDR is a buffer in the GDB process, not in the
+ inferior.
+
+ This function should only be used by target-specific code. It
+ assumes that a pointer has the same representation as that thing's
+ address represented as an integer. Some machines use word
+ addresses, or similarly munged things, for certain types of
+ pointers, so that assumption doesn't hold everywhere.
+
+ Common code should use extract_typed_address instead, or something
+ else based on POINTER_TO_ADDRESS. */
+
+CORE_ADDR
+extract_address (void *addr, int len)
+{
+ /* Assume a CORE_ADDR can fit in a LONGEST (for now). Not sure
+ whether we want this to be true eventually. */
+ return (CORE_ADDR) extract_unsigned_integer (addr, len);
+}
+
+
+/* Treat the bytes at BUF as a pointer of type TYPE, and return the
+ address it represents. */
+CORE_ADDR
+extract_typed_address (void *buf, struct type *type)
+{
+ if (TYPE_CODE (type) != TYPE_CODE_PTR
+ && TYPE_CODE (type) != TYPE_CODE_REF)
+ internal_error (__FILE__, __LINE__,
+ "extract_typed_address: "
+ "type is not a pointer or reference");
+
+ return POINTER_TO_ADDRESS (type, buf);
}
-/* 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). */
void
-read_relative_register_raw_bytes (regnum, myaddr)
- int regnum;
- char *myaddr;
+store_signed_integer (void *addr, int len, LONGEST val)
{
- register CORE_ADDR addr;
+ unsigned char *p;
+ unsigned char *startaddr = (unsigned char *) addr;
+ unsigned char *endaddr = startaddr + len;
- if (regnum == FP_REGNUM)
+ /* Start at the least significant end of the integer, and work towards
+ the most significant. */
+ if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
{
- bcopy (&selected_frame, myaddr, sizeof (CORE_ADDR));
- return;
+ for (p = endaddr - 1; p >= startaddr; --p)
+ {
+ *p = val & 0xff;
+ val >>= 8;
+ }
}
-
- addr = find_saved_register (selected_frame, regnum);
-
- if (addr)
+ else
{
- if (regnum == SP_REGNUM)
+ for (p = startaddr; p < endaddr; ++p)
{
- CORE_ADDR buffer = addr;
- bcopy (&buffer, myaddr, sizeof (CORE_ADDR));
+ *p = val & 0xff;
+ val >>= 8;
}
- else
- read_memory (addr, myaddr, REGISTER_RAW_SIZE (regnum));
- return;
}
- read_register_bytes (REGISTER_BYTE (regnum),
- myaddr, REGISTER_RAW_SIZE (regnum));
}
-/* Return a `value' with the contents of register REGNUM
- in its virtual format, with the type specified by
- REGISTER_VIRTUAL_TYPE. */
-
-value
-value_of_register (regnum)
- int regnum;
+void
+store_unsigned_integer (void *addr, int len, ULONGEST val)
{
- register CORE_ADDR addr = find_saved_register (selected_frame, regnum);
- register value val;
- char raw_buffer[MAX_REGISTER_RAW_SIZE];
- char virtual_buffer[MAX_REGISTER_VIRTUAL_SIZE];
+ unsigned char *p;
+ unsigned char *startaddr = (unsigned char *) addr;
+ unsigned char *endaddr = startaddr + len;
- if (addr)
+ /* Start at the least significant end of the integer, and work towards
+ the most significant. */
+ if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
{
- if (regnum == SP_REGNUM)
- return value_from_long (builtin_type_int, addr);
- read_memory (addr, raw_buffer, REGISTER_RAW_SIZE (regnum));
+ for (p = endaddr - 1; p >= startaddr; --p)
+ {
+ *p = val & 0xff;
+ val >>= 8;
+ }
}
else
- read_register_bytes (REGISTER_BYTE (regnum), raw_buffer,
- REGISTER_RAW_SIZE (regnum));
-
- REGISTER_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);
- VALUE_REGNO (val) = regnum;
- return val;
+ {
+ for (p = startaddr; p < endaddr; ++p)
+ {
+ *p = val & 0xff;
+ val >>= 8;
+ }
+ }
}
-\f
-/* Low level examining and depositing of registers.
-
- Note that you must call `fetch_registers' once
- before examining or depositing any registers. */
-char registers[REGISTER_BYTES];
+/* Store the address VAL as a LEN-byte value in target byte order at
+ ADDR. ADDR is a buffer in the GDB process, not in the inferior.
-/* Copy LEN bytes of consecutive data from registers
- starting with the REGBYTE'th byte of register data
- into memory at MYADDR. */
+ This function should only be used by target-specific code. It
+ assumes that a pointer has the same representation as that thing's
+ address represented as an integer. Some machines use word
+ addresses, or similarly munged things, for certain types of
+ pointers, so that assumption doesn't hold everywhere.
-read_register_bytes (regbyte, myaddr, len)
- int regbyte;
- char *myaddr;
- int len;
+ Common code should use store_typed_address instead, or something else
+ based on ADDRESS_TO_POINTER. */
+void
+store_address (void *addr, int len, LONGEST val)
{
- bcopy (®isters[regbyte], myaddr, len);
+ store_unsigned_integer (addr, len, val);
}
-/* Copy LEN bytes of consecutive data from memory at MYADDR
- into registers starting with the REGBYTE'th byte of register data. */
-write_register_bytes (regbyte, myaddr, len)
- int regbyte;
- char *myaddr;
- int len;
+/* Store the address ADDR as a pointer of type TYPE at BUF, in target
+ form. */
+void
+store_typed_address (void *buf, struct type *type, CORE_ADDR addr)
{
- bcopy (myaddr, ®isters[regbyte], len);
- if (have_inferior_p ())
- store_inferior_registers (-1);
+ if (TYPE_CODE (type) != TYPE_CODE_PTR
+ && TYPE_CODE (type) != TYPE_CODE_REF)
+ internal_error (__FILE__, __LINE__,
+ "store_typed_address: "
+ "type is not a pointer or reference");
+
+ ADDRESS_TO_POINTER (type, buf, addr);
}
-/* Return the contents of register REGNO,
- regarding it as an integer. */
+
+/* Return a `value' with the contents of (virtual or cooked) register
+ REGNUM as found in the specified FRAME. The register's type is
+ determined by REGISTER_VIRTUAL_TYPE.
+
+ NOTE: returns NULL if register value is not available. Caller will
+ check return value or die! */
+
+struct value *
+value_of_register (int regnum, struct frame_info *frame)
+{
+ CORE_ADDR addr;
+ int optim;
+ struct value *reg_val;
+ char *raw_buffer = (char*) alloca (MAX_REGISTER_RAW_SIZE);
+ enum lval_type lval;
+
+ /* Builtin registers lie completly outside of the range of normal
+ registers. Catch them early so that the target never sees them. */
+ if (regnum >= NUM_REGS + NUM_PSEUDO_REGS)
+ return value_of_builtin_reg (regnum, selected_frame);
+
+ get_saved_register (raw_buffer, &optim, &addr,
+ frame, regnum, &lval);
+
+ /* FIXME: cagney/2002-05-15: This test is just bogus.
+
+ It indicates that the target failed to supply a value for a
+ register because it was "not available" at this time. Problem
+ is, the target still has the register and so get saved_register()
+ may be returning a value saved on the stack. */
+
+ if (register_cached (regnum) < 0)
+ return NULL; /* register value not available */
+
+ reg_val = allocate_value (REGISTER_VIRTUAL_TYPE (regnum));
+
+ /* Convert raw data to virtual format if necessary. */
+
+ if (REGISTER_CONVERTIBLE (regnum))
+ {
+ REGISTER_CONVERT_TO_VIRTUAL (regnum, REGISTER_VIRTUAL_TYPE (regnum),
+ raw_buffer, VALUE_CONTENTS_RAW (reg_val));
+ }
+ else if (REGISTER_RAW_SIZE (regnum) == REGISTER_VIRTUAL_SIZE (regnum))
+ memcpy (VALUE_CONTENTS_RAW (reg_val), raw_buffer,
+ REGISTER_RAW_SIZE (regnum));
+ else
+ internal_error (__FILE__, __LINE__,
+ "Register \"%s\" (%d) has conflicting raw (%d) and virtual (%d) size",
+ REGISTER_NAME (regnum),
+ regnum,
+ REGISTER_RAW_SIZE (regnum),
+ REGISTER_VIRTUAL_SIZE (regnum));
+ VALUE_LVAL (reg_val) = lval;
+ VALUE_ADDRESS (reg_val) = addr;
+ VALUE_REGNO (reg_val) = regnum;
+ VALUE_OPTIMIZED_OUT (reg_val) = optim;
+ return reg_val;
+}
+
+/* Given a pointer of type TYPE in target form in BUF, return the
+ address it represents. */
CORE_ADDR
-read_register (regno)
- int regno;
+unsigned_pointer_to_address (struct type *type, void *buf)
{
- /* This loses when REGISTER_RAW_SIZE (regno) != sizeof (int) */
- return *(int *) ®isters[REGISTER_BYTE (regno)];
+ return extract_address (buf, TYPE_LENGTH (type));
}
-/* Store VALUE in the register number REGNO, regarded as an integer. */
+CORE_ADDR
+signed_pointer_to_address (struct type *type, void *buf)
+{
+ return extract_signed_integer (buf, TYPE_LENGTH (type));
+}
+/* Given an address, store it as a pointer of type TYPE in target
+ format in BUF. */
void
-write_register (regno, val)
- int regno, val;
+unsigned_address_to_pointer (struct type *type, void *buf, CORE_ADDR addr)
{
- /* This loses when REGISTER_RAW_SIZE (regno) != sizeof (int) */
-#if defined(sun4)
- /* This is a no-op on a Sun 4. */
- if (regno == 0)
- return;
-#endif
-
- *(int *) ®isters[REGISTER_BYTE (regno)] = val;
-
- if (have_inferior_p ())
- store_inferior_registers (regno);
+ store_address (buf, TYPE_LENGTH (type), addr);
}
-/* Record that register REGNO contains VAL.
- This is used when the value is obtained from the inferior or core dump,
- so there is no need to store the value there. */
-
void
-supply_register (regno, val)
- int regno;
- char *val;
+address_to_signed_pointer (struct type *type, void *buf, CORE_ADDR addr)
{
- bcopy (val, ®isters[REGISTER_BYTE (regno)], REGISTER_RAW_SIZE (regno));
+ store_signed_integer (buf, TYPE_LENGTH (type), addr);
}
\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. */
-
-value
-read_var_value (var, frame)
- register struct symbol *var;
- FRAME frame;
+/* Will calling read_var_value or locate_var_value on SYM end
+ up caring what frame it is being evaluated relative to? SYM must
+ be non-NULL. */
+int
+symbol_read_needs_frame (struct symbol *sym)
{
- register value v;
+ switch (SYMBOL_CLASS (sym))
+ {
+ /* All cases listed explicitly so that gcc -Wall will detect it if
+ we failed to consider one. */
+ case LOC_REGISTER:
+ case LOC_ARG:
+ case LOC_REF_ARG:
+ case LOC_REGPARM:
+ case LOC_REGPARM_ADDR:
+ case LOC_LOCAL:
+ case LOC_LOCAL_ARG:
+ case LOC_BASEREG:
+ case LOC_BASEREG_ARG:
+ case LOC_THREAD_LOCAL_STATIC:
+ return 1;
+
+ case LOC_UNDEF:
+ case LOC_CONST:
+ case LOC_STATIC:
+ case LOC_INDIRECT:
+ case LOC_TYPEDEF:
+
+ case LOC_LABEL:
+ /* Getting the address of a label can be done independently of the block,
+ even if some *uses* of that address wouldn't work so well without
+ the right frame. */
- struct frame_info fi;
+ case LOC_BLOCK:
+ case LOC_CONST_BYTES:
+ case LOC_UNRESOLVED:
+ case LOC_OPTIMIZED_OUT:
+ return 0;
+ }
+ return 1;
+}
+/* Given a struct symbol for a variable,
+ 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. */
+
+struct value *
+read_var_value (register struct symbol *var, struct frame_info *frame)
+{
+ register struct value *v;
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);
VALUE_LVAL (v) = lval_memory; /* The most likely possibility. */
+ VALUE_BFD_SECTION (v) = SYMBOL_BFD_SECTION (var);
+
len = TYPE_LENGTH (type);
- if (frame == 0) frame = selected_frame;
+ if (frame == NULL)
+ frame = selected_frame;
switch (SYMBOL_CLASS (var))
{
case LOC_CONST:
- case LOC_LABEL:
- bcopy (&val, VALUE_CONTENTS (v), len);
+ /* Put the constant back in target format. */
+ store_signed_integer (VALUE_CONTENTS_RAW (v), len,
+ (LONGEST) SYMBOL_VALUE (var));
VALUE_LVAL (v) = not_lval;
return v;
- case LOC_CONST_BYTES:
- bcopy (val, VALUE_CONTENTS (v), len);
+ case LOC_LABEL:
+ /* Put the constant back in target format. */
+ if (overlay_debugging)
+ {
+ CORE_ADDR addr
+ = symbol_overlayed_address (SYMBOL_VALUE_ADDRESS (var),
+ SYMBOL_BFD_SECTION (var));
+ store_typed_address (VALUE_CONTENTS_RAW (v), type, addr);
+ }
+ else
+ store_typed_address (VALUE_CONTENTS_RAW (v), type,
+ SYMBOL_VALUE_ADDRESS (var));
VALUE_LVAL (v) = not_lval;
return v;
+ case LOC_CONST_BYTES:
+ {
+ char *bytes_addr;
+ bytes_addr = SYMBOL_VALUE_BYTES (var);
+ memcpy (VALUE_CONTENTS_RAW (v), bytes_addr, len);
+ VALUE_LVAL (v) = not_lval;
+ return v;
+ }
+
case LOC_STATIC:
- addr = val;
+ if (overlay_debugging)
+ addr = symbol_overlayed_address (SYMBOL_VALUE_ADDRESS (var),
+ SYMBOL_BFD_SECTION (var));
+ else
+ addr = SYMBOL_VALUE_ADDRESS (var);
break;
+ case LOC_INDIRECT:
+ {
+ /* The import slot does not have a real address in it from the
+ dynamic loader (dld.sl on HP-UX), if the target hasn't
+ begun execution yet, so check for that. */
+ CORE_ADDR locaddr;
+ struct value *loc;
+ if (!target_has_execution)
+ error ("\
+Attempt to access variable defined in different shared object or load module when\n\
+addresses have not been bound by the dynamic loader. Try again when executable is running.");
+
+ locaddr = SYMBOL_VALUE_ADDRESS (var);
+ loc = value_at (lookup_pointer_type (type), locaddr, NULL);
+ addr = value_as_address (loc);
+ }
+
case LOC_ARG:
- fi = get_frame_info (frame);
- addr = val + FRAME_ARGS_ADDRESS (fi);
+ if (frame == NULL)
+ return 0;
+ addr = FRAME_ARGS_ADDRESS (frame);
+ if (!addr)
+ return 0;
+ addr += SYMBOL_VALUE (var);
break;
+ case LOC_REF_ARG:
+ {
+ struct value *ref;
+ CORE_ADDR argref;
+ if (frame == NULL)
+ return 0;
+ argref = FRAME_ARGS_ADDRESS (frame);
+ if (!argref)
+ return 0;
+ argref += SYMBOL_VALUE (var);
+ ref = value_at (lookup_pointer_type (type), argref, NULL);
+ addr = value_as_address (ref);
+ break;
+ }
+
case LOC_LOCAL:
- fi = get_frame_info (frame);
- addr = val + FRAME_LOCALS_ADDRESS (fi);
+ case LOC_LOCAL_ARG:
+ if (frame == NULL)
+ return 0;
+ addr = FRAME_LOCALS_ADDRESS (frame);
+ addr += SYMBOL_VALUE (var);
break;
+ case LOC_BASEREG:
+ case LOC_BASEREG_ARG:
+ case LOC_THREAD_LOCAL_STATIC:
+ {
+ struct value *regval;
+
+ regval = value_from_register (lookup_pointer_type (type),
+ SYMBOL_BASEREG (var), frame);
+ if (regval == NULL)
+ error ("Value of base register not available.");
+ addr = value_as_address (regval);
+ 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));
+ if (overlay_debugging)
+ VALUE_ADDRESS (v) = symbol_overlayed_address
+ (BLOCK_START (SYMBOL_BLOCK_VALUE (var)), SYMBOL_BFD_SECTION (var));
+ else
+ VALUE_ADDRESS (v) = BLOCK_START (SYMBOL_BLOCK_VALUE (var));
return v;
case LOC_REGISTER:
case LOC_REGPARM:
+ case LOC_REGPARM_ADDR:
{
- char raw_buffer[MAX_REGISTER_RAW_SIZE];
- char virtual_buffer[MAX_REGISTER_VIRTUAL_SIZE];
-
- VALUE_REGNO (v) = val;
+ struct block *b;
+ int regno = SYMBOL_VALUE (var);
+ struct value *regval;
- /* Locate the register's contents in a real register or in core;
- read the data in raw format. */
+ if (frame == NULL)
+ return 0;
+ b = get_frame_block (frame, 0);
- addr = find_saved_register (frame, val);
- if (addr == 0)
+ if (SYMBOL_CLASS (var) == LOC_REGPARM_ADDR)
{
- /* Value is really in a register. */
+ regval = value_from_register (lookup_pointer_type (type),
+ regno,
+ frame);
- VALUE_LVAL (v) = lval_register;
- VALUE_ADDRESS (v) = REGISTER_BYTE (val);
+ if (regval == NULL)
+ error ("Value of register variable not available.");
- read_register_bytes (REGISTER_BYTE (val),
- raw_buffer, REGISTER_RAW_SIZE (val));
+ addr = value_as_address (regval);
+ VALUE_LVAL (v) = lval_memory;
}
else
{
- /* Value was in a register that has been saved in memory. */
+ regval = value_from_register (type, regno, frame);
- read_memory (addr, raw_buffer, REGISTER_RAW_SIZE (val));
- VALUE_ADDRESS (v) = addr;
+ if (regval == NULL)
+ error ("Value of register variable not available.");
+ return regval;
}
+ }
+ break;
+
+ case LOC_UNRESOLVED:
+ {
+ struct minimal_symbol *msym;
+
+ msym = lookup_minimal_symbol (SYMBOL_NAME (var), NULL, NULL);
+ if (msym == NULL)
+ return 0;
+ if (overlay_debugging)
+ addr = symbol_overlayed_address (SYMBOL_VALUE_ADDRESS (msym),
+ SYMBOL_BFD_SECTION (msym));
+ else
+ addr = SYMBOL_VALUE_ADDRESS (msym);
+ }
+ break;
+
+ case LOC_OPTIMIZED_OUT:
+ VALUE_LVAL (v) = not_lval;
+ VALUE_OPTIMIZED_OUT (v) = 1;
+ return v;
+
+ default:
+ error ("Cannot look up value of a botched symbol.");
+ break;
+ }
+
+ VALUE_ADDRESS (v) = addr;
+ VALUE_LAZY (v) = 1;
+ return v;
+}
- /* Convert the raw contents to virtual contents.
- (Just copy them if the formats are the same.) */
+/* Return a value of type TYPE, stored in register REGNUM, in frame
+ FRAME.
- REGISTER_CONVERT_TO_VIRTUAL (val, raw_buffer, virtual_buffer);
+ NOTE: returns NULL if register value is not available.
+ Caller will check return value or die! */
- if (REGISTER_CONVERTIBLE (val))
- {
- /* When the raw and virtual formats differ, the virtual format
- corresponds to a specific data type. If we want that type,
- copy the data into the value.
- Otherwise, do a type-conversion. */
+struct value *
+value_from_register (struct type *type, int regnum, struct frame_info *frame)
+{
+ char *raw_buffer = (char*) alloca (MAX_REGISTER_RAW_SIZE);
+ CORE_ADDR addr;
+ int optim;
+ struct value *v = allocate_value (type);
+ char *value_bytes = 0;
+ int value_bytes_copied = 0;
+ int num_storage_locs;
+ enum lval_type lval;
+ int len;
+
+ CHECK_TYPEDEF (type);
+ len = TYPE_LENGTH (type);
+
+ VALUE_REGNO (v) = regnum;
+
+ num_storage_locs = (len > REGISTER_VIRTUAL_SIZE (regnum) ?
+ ((len - 1) / REGISTER_RAW_SIZE (regnum)) + 1 :
+ 1);
- if (type != REGISTER_VIRTUAL_TYPE (val))
+ if (num_storage_locs > 1
+#ifdef GDB_TARGET_IS_H8500
+ || TYPE_CODE (type) == TYPE_CODE_PTR
+#endif
+ )
+ {
+ /* Value spread across multiple storage locations. */
+
+ int local_regnum;
+ int mem_stor = 0, reg_stor = 0;
+ int mem_tracking = 1;
+ CORE_ADDR last_addr = 0;
+ CORE_ADDR first_addr = 0;
+
+ value_bytes = (char *) alloca (len + MAX_REGISTER_RAW_SIZE);
+
+ /* Copy all of the data out, whereever it may be. */
+
+#ifdef GDB_TARGET_IS_H8500
+/* This piece of hideosity is required because the H8500 treats registers
+ differently depending upon whether they are used as pointers or not. As a
+ pointer, a register needs to have a page register tacked onto the front.
+ An alternate way to do this would be to have gcc output different register
+ numbers for the pointer & non-pointer form of the register. But, it
+ doesn't, so we're stuck with this. */
+
+ if (TYPE_CODE (type) == TYPE_CODE_PTR
+ && len > 2)
+ {
+ int page_regnum;
+
+ switch (regnum)
+ {
+ case R0_REGNUM:
+ case R1_REGNUM:
+ case R2_REGNUM:
+ case R3_REGNUM:
+ page_regnum = SEG_D_REGNUM;
+ break;
+ case R4_REGNUM:
+ case R5_REGNUM:
+ page_regnum = SEG_E_REGNUM;
+ break;
+ case R6_REGNUM:
+ case R7_REGNUM:
+ page_regnum = SEG_T_REGNUM;
+ break;
+ }
+
+ value_bytes[0] = 0;
+ get_saved_register (value_bytes + 1,
+ &optim,
+ &addr,
+ frame,
+ page_regnum,
+ &lval);
+
+ if (register_cached (page_regnum) == -1)
+ return NULL; /* register value not available */
+
+ if (lval == lval_register)
+ reg_stor++;
+ else
+ mem_stor++;
+ first_addr = addr;
+ last_addr = addr;
+
+ get_saved_register (value_bytes + 2,
+ &optim,
+ &addr,
+ frame,
+ regnum,
+ &lval);
+
+ if (register_cached (regnum) == -1)
+ return NULL; /* register value not available */
+
+ if (lval == lval_register)
+ reg_stor++;
+ else
+ {
+ mem_stor++;
+ mem_tracking = mem_tracking && (addr == last_addr);
+ }
+ last_addr = addr;
+ }
+ else
+#endif /* GDB_TARGET_IS_H8500 */
+ for (local_regnum = regnum;
+ value_bytes_copied < len;
+ (value_bytes_copied += REGISTER_RAW_SIZE (local_regnum),
+ ++local_regnum))
+ {
+ get_saved_register (value_bytes + value_bytes_copied,
+ &optim,
+ &addr,
+ frame,
+ local_regnum,
+ &lval);
+
+ if (register_cached (local_regnum) == -1)
+ return NULL; /* register value not available */
+
+ if (regnum == local_regnum)
+ first_addr = addr;
+ if (lval == lval_register)
+ reg_stor++;
+ else
{
- /* eg a variable of type `float' in a 68881 register
- with raw type `extended' and virtual type `double'.
- Fetch it as a `double' and then convert to `float'. */
- v = allocate_value (REGISTER_VIRTUAL_TYPE (val));
- bcopy (virtual_buffer, VALUE_CONTENTS (v), len);
- v = value_cast (type, v);
+ mem_stor++;
+
+ mem_tracking =
+ (mem_tracking
+ && (regnum == local_regnum
+ || addr == last_addr));
}
- else
- bcopy (virtual_buffer, VALUE_CONTENTS (v), len);
+ last_addr = addr;
}
- else
- {
- /* Raw and virtual formats are the same for this register. */
- union { int i; char c; } test;
- /* If we want less than the full size, we need to
- test for a big-endian or little-endian machine. */
- test.i = 1;
- if (test.c != 1 && len < REGISTER_RAW_SIZE (val))
- {
- /* Big-endian, and we want less than full size. */
- VALUE_OFFSET (v) = REGISTER_RAW_SIZE (val) - len;
- }
+ if ((reg_stor && mem_stor)
+ || (mem_stor && !mem_tracking))
+ /* Mixed storage; all of the hassle we just went through was
+ for some good purpose. */
+ {
+ VALUE_LVAL (v) = lval_reg_frame_relative;
+ VALUE_FRAME (v) = FRAME_FP (frame);
+ VALUE_FRAME_REGNUM (v) = regnum;
+ }
+ else if (mem_stor)
+ {
+ VALUE_LVAL (v) = lval_memory;
+ VALUE_ADDRESS (v) = first_addr;
+ }
+ else if (reg_stor)
+ {
+ VALUE_LVAL (v) = lval_register;
+ VALUE_ADDRESS (v) = first_addr;
+ }
+ else
+ internal_error (__FILE__, __LINE__,
+ "value_from_register: Value not stored anywhere!");
- bcopy (virtual_buffer + VALUE_OFFSET (v),
- VALUE_CONTENTS (v), len);
- }
+ VALUE_OPTIMIZED_OUT (v) = optim;
- return v;
- }
+ /* Any structure stored in more than one register will always be
+ 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. */
+ memcpy (VALUE_CONTENTS_RAW (v), value_bytes, len);
+
+ /* Finally do any conversion necessary when extracting this
+ type from more than one register. */
+#ifdef REGISTER_CONVERT_TO_TYPE
+ REGISTER_CONVERT_TO_TYPE (regnum, type, VALUE_CONTENTS_RAW (v));
+#endif
+ return v;
}
- read_memory (addr, VALUE_CONTENTS (v), len);
+ /* 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. */
+
+ get_saved_register (raw_buffer, &optim, &addr, frame, regnum, &lval);
+
+ if (register_cached (regnum) == -1)
+ return NULL; /* register value not available */
+
+ VALUE_OPTIMIZED_OUT (v) = optim;
+ VALUE_LVAL (v) = lval;
VALUE_ADDRESS (v) = addr;
+
+ /* Convert the raw register to the corresponding data value's memory
+ format, if necessary. */
+
+ if (CONVERT_REGISTER_P (regnum))
+ {
+ REGISTER_TO_VALUE (regnum, type, raw_buffer, VALUE_CONTENTS_RAW (v));
+ }
+ else
+ {
+ /* Raw and virtual formats are the same for this register. */
+
+ if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG && len < REGISTER_RAW_SIZE (regnum))
+ {
+ /* Big-endian, and we want less than full size. */
+ VALUE_OFFSET (v) = REGISTER_RAW_SIZE (regnum) - len;
+ }
+
+ memcpy (VALUE_CONTENTS_RAW (v), raw_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;
+struct value *
+locate_var_value (register struct symbol *var, struct frame_info *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);
+ struct 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))
- {
- case LOC_CONST:
- case LOC_CONST_BYTES:
- error ("Address requested for identifier \"%s\" which is a constant.",
- SYMBOL_NAME (var));
+ lazy_value = read_var_value (var, frame);
+ if (lazy_value == 0)
+ error ("Address of \"%s\" is unknown.", SYMBOL_SOURCE_NAME (var));
- case LOC_REGISTER:
- case LOC_REGPARM:
- addr = find_saved_register (frame, val);
- if (addr != 0)
- {
- union { int i; char c; } test;
- int len = TYPE_LENGTH (type);
- /* If var is less than the full size of register, we need to
- test for a big-endian or little-endian machine. */
- test.i = 1;
- if (test.c != 1 && len < REGISTER_RAW_SIZE (val))
- /* Big-endian, and we want less than full size. */
- addr += REGISTER_RAW_SIZE (val) - len;
- break;
- }
- error ("Address requested for identifier \"%s\" which is in a register.",
- SYMBOL_NAME (var));
+ if (VALUE_LAZY (lazy_value)
+ || TYPE_CODE (type) == TYPE_CODE_FUNC)
+ {
+ struct value *val;
- case LOC_STATIC:
- case LOC_LABEL:
- addr = val;
- break;
+ addr = VALUE_ADDRESS (lazy_value);
+ val = value_from_pointer (lookup_pointer_type (type), addr);
+ VALUE_BFD_SECTION (val) = VALUE_BFD_SECTION (lazy_value);
+ return val;
+ }
- case LOC_ARG:
- fi = get_frame_info (frame);
- addr = val + FRAME_ARGS_ADDRESS (fi);
+ /* Not a memory address; check what the problem was. */
+ switch (VALUE_LVAL (lazy_value))
+ {
+ case lval_register:
+ gdb_assert (REGISTER_NAME (VALUE_REGNO (lazy_value)) != NULL
+ && *REGISTER_NAME (VALUE_REGNO (lazy_value)) != '\0');
+ error("Address requested for identifier "
+ "\"%s\" which is in register $%s",
+ SYMBOL_SOURCE_NAME (var),
+ REGISTER_NAME (VALUE_REGNO (lazy_value)));
break;
- case LOC_LOCAL:
- fi = get_frame_info (frame);
- addr = val + FRAME_LOCALS_ADDRESS (fi);
+ case lval_reg_frame_relative:
+ gdb_assert (REGISTER_NAME (VALUE_FRAME_REGNUM (lazy_value)) != NULL
+ && *REGISTER_NAME (VALUE_FRAME_REGNUM (lazy_value)) != '\0');
+ error("Address requested for identifier "
+ "\"%s\" which is in frame register $%s",
+ SYMBOL_SOURCE_NAME (var),
+ REGISTER_NAME (VALUE_FRAME_REGNUM (lazy_value)));
break;
- case LOC_TYPEDEF:
- error ("Address requested for identifier \"%s\" which is a typedef.",
- SYMBOL_NAME (var));
-
- case LOC_BLOCK:
- addr = BLOCK_START (SYMBOL_BLOCK_VALUE (var));
+ default:
+ error ("Can't take address of \"%s\" which isn't an lvalue.",
+ SYMBOL_SOURCE_NAME (var));
break;
}
-
- return value_cast (lookup_pointer_type (type),
- value_from_long (builtin_type_long, addr));
+ return 0; /* For lint -- never reached */
}
-
-static
-initialize ()
-{}
-
-END_FILE