/* Cache and manage the values of registers for GDB, the GNU debugger.
- Copyright 1986, 87, 89, 91, 94, 95, 96, 1998, 2000, 2001
+ Copyright 1986, 1987, 1989, 1991, 1994, 1995, 1996, 1998, 2000, 2001
Free Software Foundation, Inc.
This file is part of GDB.
Boston, MA 02111-1307, USA. */
#include "defs.h"
-#include "frame.h"
#include "inferior.h"
#include "target.h"
#include "gdbarch.h"
#include "gdbcmd.h"
+#include "regcache.h"
+#include "gdb_assert.h"
/*
* DATA STRUCTURE
/* REGISTER_VALID is 0 if the register needs to be fetched,
1 if it has been fetched, and
-1 if the register value was not available.
- "Not available" means don't try to fetch it again. */
+
+ "Not available" indicates that the target is not not able to supply
+ the register at this state. The register may become available at a
+ later time (after the next resume). This often occures when GDB is
+ manipulating a target that contains only a snapshot of the entire
+ system being debugged - some of the registers in such a system may
+ not have been saved. */
signed char *register_valid;
-/* The thread/process associated with the current set of registers.
- For now, -1 is special, and means `no current process'. */
+/* The thread/process associated with the current set of registers. */
-static int registers_pid = -1;
+static ptid_t registers_ptid;
/*
* FUNCTIONS:
/* If REGNUM >= 0, return a pointer to register REGNUM's cache buffer area,
else return a pointer to the start of the cache buffer. */
-char *
+static char *
register_buffer (int regnum)
{
- if (regnum < 0)
- return registers;
- else
- return ®isters[REGISTER_BYTE (regnum)];
+ gdb_assert (regnum >= 0 && regnum < (NUM_REGS + NUM_PSEUDO_REGS));
+ return ®isters[REGISTER_BYTE (regnum)];
}
/* Return whether register REGNUM is a real register. */
static void
fetch_register (int regnum)
{
- if (real_register (regnum))
- target_fetch_registers (regnum);
- else if (pseudo_register (regnum))
+ /* NOTE: cagney/2001-12-04: Legacy targets were using fetch/store
+ pseudo-register as a way of handling registers that needed to be
+ constructed from one or more raw registers. New targets instead
+ use gdbarch register read/write. */
+ if (FETCH_PSEUDO_REGISTER_P ()
+ && pseudo_register (regnum))
FETCH_PSEUDO_REGISTER (regnum);
+ else
+ target_fetch_registers (regnum);
}
/* Write register REGNUM cached value to the target. */
static void
store_register (int regnum)
{
- if (real_register (regnum))
- target_store_registers (regnum);
- else if (pseudo_register (regnum))
+ /* NOTE: cagney/2001-12-04: Legacy targets were using fetch/store
+ pseudo-register as a way of handling registers that needed to be
+ constructed from one or more raw registers. New targets instead
+ use gdbarch register read/write. */
+ if (STORE_PSEUDO_REGISTER_P ()
+ && pseudo_register (regnum))
STORE_PSEUDO_REGISTER (regnum);
+ else
+ target_store_registers (regnum);
}
/* Low level examining and depositing of registers.
{
int i;
- registers_pid = -1;
+ registers_ptid = pid_to_ptid (-1);
/* Force cleanup of any alloca areas if using C alloca instead of
a builtin alloca. This particular call is used to clean up
gdb gives control to the user (ie watchpoints). */
alloca (0);
- for (i = 0; i < ARCH_NUM_REGS; i++)
- set_register_cached (i, 0);
-
- /* Assume that if all the hardware regs have changed,
- then so have the pseudo-registers. */
- for (i = NUM_REGS; i < NUM_REGS + NUM_PSEUDO_REGS; i++)
+ for (i = 0; i < NUM_REGS + NUM_PSEUDO_REGS; i++)
set_register_cached (i, 0);
if (registers_changed_hook)
Indicate that all registers have been fetched, so mark them all valid. */
+/* NOTE: cagney/2001-12-04: This function does not set valid on the
+ pseudo-register range since pseudo registers are always supplied
+ using supply_register(). */
+/* FIXME: cagney/2001-12-04: This function is DEPRECATED. The target
+ code was blatting the registers[] array and then calling this.
+ Since targets should only be using supply_register() the need for
+ this function/hack is eliminated. */
void
registers_fetched (void)
{
int i;
- for (i = 0; i < ARCH_NUM_REGS; i++)
+ for (i = 0; i < NUM_REGS; i++)
set_register_cached (i, 1);
/* Do not assume that the pseudo-regs have also been fetched.
- Fetching all real regs might not account for all pseudo-regs. */
+ Fetching all real regs NEVER accounts for pseudo-regs. */
}
/* read_register_bytes and write_register_bytes are generally a *BAD*
into memory at MYADDR. */
void
-read_register_bytes (int inregbyte, char *myaddr, int inlen)
+read_register_bytes (int in_start, char *in_buf, int in_len)
{
- int inregend = inregbyte + inlen;
+ int in_end = in_start + in_len;
int regnum;
-
- if (registers_pid != inferior_pid)
- {
- registers_changed ();
- registers_pid = inferior_pid;
- }
+ char *reg_buf = alloca (MAX_REGISTER_RAW_SIZE);
/* See if we are trying to read bytes from out-of-date registers. If so,
update just those registers. */
for (regnum = 0; regnum < NUM_REGS + NUM_PSEUDO_REGS; regnum++)
{
- int regstart, regend;
-
- if (register_cached (regnum))
+ int reg_start;
+ int reg_end;
+ int reg_len;
+ int start;
+ int end;
+ int byte;
+
+ reg_start = REGISTER_BYTE (regnum);
+ reg_len = REGISTER_RAW_SIZE (regnum);
+ reg_end = reg_start + reg_len;
+
+ if (reg_end <= in_start || in_end <= reg_start)
+ /* The range the user wants to read doesn't overlap with regnum. */
continue;
- if (REGISTER_NAME (regnum) == NULL || *REGISTER_NAME (regnum) == '\0')
+ if (REGISTER_NAME (regnum) != NULL && *REGISTER_NAME (regnum) != '\0')
+ /* Force the cache to fetch the entire register. */
+ read_register_gen (regnum, reg_buf);
+ else
+ /* Legacy note: even though this register is ``invalid'' we
+ still need to return something. It would appear that some
+ code relies on apparent gaps in the register array also
+ being returned. */
+ /* FIXME: cagney/2001-08-18: This is just silly. It defeats
+ the entire register read/write flow of control. Must
+ resist temptation to return 0xdeadbeef. */
+ memcpy (reg_buf, registers + reg_start, reg_len);
+
+ /* Legacy note: This function, for some reason, allows a NULL
+ input buffer. If the buffer is NULL, the registers are still
+ fetched, just the final transfer is skipped. */
+ if (in_buf == NULL)
continue;
- regstart = REGISTER_BYTE (regnum);
- regend = regstart + REGISTER_RAW_SIZE (regnum);
-
- if (regend <= inregbyte || inregend <= regstart)
- /* The range the user wants to read doesn't overlap with regnum. */
- continue;
+ /* start = max (reg_start, in_start) */
+ if (reg_start > in_start)
+ start = reg_start;
+ else
+ start = in_start;
- /* We've found an uncached register where at least one byte will be read.
- Update it from the target. */
- fetch_register (regnum);
+ /* end = min (reg_end, in_end) */
+ if (reg_end < in_end)
+ end = reg_end;
+ else
+ end = in_end;
- if (!register_cached (regnum))
+ /* Transfer just the bytes common to both IN_BUF and REG_BUF */
+ for (byte = start; byte < end; byte++)
{
- /* Sometimes pseudoregs are never marked valid, so that they
- will be fetched every time (it can be complicated to know
- if a pseudoreg is valid, while "fetching" them can be cheap).
- */
- if (regnum < NUM_REGS)
- error ("read_register_bytes: Couldn't update register %d.", regnum);
+ in_buf[byte - in_start] = reg_buf[byte - reg_start];
}
}
-
- if (myaddr != NULL)
- memcpy (myaddr, register_buffer (-1) + inregbyte, inlen);
}
/* Read register REGNUM into memory at MYADDR, which must be large
register is known to be the size of a CORE_ADDR or smaller,
read_register can be used instead. */
-void
-read_register_gen (int regnum, char *myaddr)
+static void
+legacy_read_register_gen (int regnum, char *myaddr)
{
- if (registers_pid != inferior_pid)
+ gdb_assert (regnum >= 0 && regnum < (NUM_REGS + NUM_PSEUDO_REGS));
+ if (! ptid_equal (registers_ptid, inferior_ptid))
{
registers_changed ();
- registers_pid = inferior_pid;
+ registers_ptid = inferior_ptid;
}
if (!register_cached (regnum))
REGISTER_RAW_SIZE (regnum));
}
+void
+regcache_read (int rawnum, char *buf)
+{
+ gdb_assert (rawnum >= 0 && rawnum < (NUM_REGS + NUM_PSEUDO_REGS));
+ /* For moment, just use underlying legacy code. Ulgh!!! */
+ legacy_read_register_gen (rawnum, buf);
+}
+
+void
+read_register_gen (int regnum, char *buf)
+{
+ if (! gdbarch_register_read_p (current_gdbarch))
+ {
+ legacy_read_register_gen (regnum, buf);
+ return;
+ }
+ gdbarch_register_read (current_gdbarch, regnum, buf);
+}
+
+
/* Write register REGNUM at MYADDR to the target. MYADDR points at
REGISTER_RAW_BYTES(REGNUM), which must be in target byte-order. */
-/* Registers we shouldn't try to store. */
-#if !defined (CANNOT_STORE_REGISTER)
-#define CANNOT_STORE_REGISTER(regnum) 0
-#endif
-
-void
-write_register_gen (int regnum, char *myaddr)
+static void
+legacy_write_register_gen (int regnum, char *myaddr)
{
int size;
+ gdb_assert (regnum >= 0 && regnum < (NUM_REGS + NUM_PSEUDO_REGS));
/* 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 (regnum))
return;
- if (registers_pid != inferior_pid)
+ if (! ptid_equal (registers_ptid, inferior_ptid))
{
registers_changed ();
- registers_pid = inferior_pid;
+ registers_ptid = inferior_ptid;
}
size = REGISTER_RAW_SIZE (regnum);
- /* If we have a valid copy of the register, and new value == old value,
- then don't bother doing the actual store. */
-
- if (register_cached (regnum)
- && memcmp (register_buffer (regnum), myaddr, size) == 0)
- return;
-
if (real_register (regnum))
- target_prepare_to_store ();
+ {
+ /* If we have a valid copy of the register, and new value == old
+ value, then don't bother doing the actual store. */
+ if (register_cached (regnum)
+ && memcmp (register_buffer (regnum), myaddr, size) == 0)
+ return;
+ else
+ target_prepare_to_store ();
+ }
memcpy (register_buffer (regnum), myaddr, size);
store_register (regnum);
}
+void
+regcache_write (int rawnum, char *buf)
+{
+ gdb_assert (rawnum >= 0 && rawnum < (NUM_REGS + NUM_PSEUDO_REGS));
+ /* For moment, just use underlying legacy code. Ulgh!!! */
+ legacy_write_register_gen (rawnum, buf);
+}
+
+void
+write_register_gen (int regnum, char *buf)
+{
+ if (! gdbarch_register_write_p (current_gdbarch))
+ {
+ legacy_write_register_gen (regnum, buf);
+ return;
+ }
+ gdbarch_register_write (current_gdbarch, regnum, buf);
+}
+
/* Copy INLEN bytes of consecutive data from memory at MYADDR
into registers starting with the MYREGSTART'th byte of register data. */
ULONGEST
read_register (int regnum)
{
- if (registers_pid != inferior_pid)
- {
- registers_changed ();
- registers_pid = inferior_pid;
- }
-
- if (!register_cached (regnum))
- fetch_register (regnum);
-
- return (extract_unsigned_integer (register_buffer (regnum),
- REGISTER_RAW_SIZE (regnum)));
+ char *buf = alloca (REGISTER_RAW_SIZE (regnum));
+ read_register_gen (regnum, buf);
+ return (extract_unsigned_integer (buf, REGISTER_RAW_SIZE (regnum)));
}
ULONGEST
-read_register_pid (int regnum, int pid)
+read_register_pid (int regnum, ptid_t ptid)
{
+ ptid_t save_ptid;
int save_pid;
CORE_ADDR retval;
- if (pid == inferior_pid)
+ if (ptid_equal (ptid, inferior_ptid))
return read_register (regnum);
- save_pid = inferior_pid;
+ save_ptid = inferior_ptid;
- inferior_pid = pid;
+ inferior_ptid = ptid;
retval = read_register (regnum);
- inferior_pid = save_pid;
+ inferior_ptid = save_ptid;
return retval;
}
LONGEST
read_signed_register (int regnum)
{
- if (registers_pid != inferior_pid)
- {
- registers_changed ();
- registers_pid = inferior_pid;
- }
-
- if (!register_cached (regnum))
- fetch_register (regnum);
-
- return (extract_signed_integer (register_buffer (regnum),
- REGISTER_RAW_SIZE (regnum)));
+ void *buf = alloca (REGISTER_RAW_SIZE (regnum));
+ read_register_gen (regnum, buf);
+ return (extract_signed_integer (buf, REGISTER_RAW_SIZE (regnum)));
}
LONGEST
-read_signed_register_pid (int regnum, int pid)
+read_signed_register_pid (int regnum, ptid_t ptid)
{
- int save_pid;
+ ptid_t save_ptid;
LONGEST retval;
- if (pid == inferior_pid)
+ if (ptid_equal (ptid, inferior_ptid))
return read_signed_register (regnum);
- save_pid = inferior_pid;
+ save_ptid = inferior_ptid;
- inferior_pid = pid;
+ inferior_ptid = ptid;
retval = read_signed_register (regnum);
- inferior_pid = save_pid;
+ inferior_ptid = save_ptid;
return retval;
}
void
write_register (int regnum, LONGEST val)
{
- PTR buf;
+ void *buf;
int size;
-
- /* 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 (regnum))
- return;
-
- if (registers_pid != inferior_pid)
- {
- registers_changed ();
- registers_pid = inferior_pid;
- }
-
size = REGISTER_RAW_SIZE (regnum);
buf = alloca (size);
store_signed_integer (buf, size, (LONGEST) val);
-
- /* If we have a valid copy of the register, and new value == old value,
- then don't bother doing the actual store. */
-
- if (register_cached (regnum)
- && memcmp (register_buffer (regnum), buf, size) == 0)
- return;
-
- if (real_register (regnum))
- target_prepare_to_store ();
-
- memcpy (register_buffer (regnum), buf, size);
-
- set_register_cached (regnum, 1);
- store_register (regnum);
+ write_register_gen (regnum, buf);
}
void
-write_register_pid (int regnum, CORE_ADDR val, int pid)
+write_register_pid (int regnum, CORE_ADDR val, ptid_t ptid)
{
- int save_pid;
+ ptid_t save_ptid;
- if (pid == inferior_pid)
+ if (ptid_equal (ptid, inferior_ptid))
{
write_register (regnum, val);
return;
}
- save_pid = inferior_pid;
+ save_ptid = inferior_ptid;
- inferior_pid = pid;
+ inferior_ptid = ptid;
write_register (regnum, val);
- inferior_pid = save_pid;
+ inferior_ptid = save_ptid;
}
/* SUPPLY_REGISTER()
supply_register (int regnum, char *val)
{
#if 1
- if (registers_pid != inferior_pid)
+ if (! ptid_equal (registers_ptid, inferior_ptid))
{
registers_changed ();
- registers_pid = inferior_pid;
+ registers_ptid = inferior_ptid;
}
#endif
/* On some architectures, e.g. HPPA, there are a few stray bits in
some registers, that the rest of the code would like to ignore. */
-#ifdef CLEAN_UP_REGISTER_VALUE
- CLEAN_UP_REGISTER_VALUE (regnum, register_buffer (regnum));
+ /* NOTE: cagney/2001-03-16: The macro CLEAN_UP_REGISTER_VALUE is
+ going to be deprecated. Instead architectures will leave the raw
+ register value as is and instead clean things up as they pass
+ through the method gdbarch_register_read() clean up the
+ values. */
+
+#ifdef DEPRECATED_CLEAN_UP_REGISTER_VALUE
+ DEPRECATED_CLEAN_UP_REGISTER_VALUE (regnum, register_buffer (regnum));
#endif
}
-/* read_pc, write_pc, read_sp, write_sp, read_fp, write_fp, etc.
- Special handling for registers PC, SP, and FP. */
+void
+regcache_collect (int regnum, void *buf)
+{
+ memcpy (buf, register_buffer (regnum), REGISTER_RAW_SIZE (regnum));
+}
+
+
+/* read_pc, write_pc, read_sp, write_sp, read_fp, etc. Special
+ handling for registers PC, SP, and FP. */
+
+/* NOTE: cagney/2001-02-18: The functions generic_target_read_pc(),
+ read_pc_pid(), read_pc(), generic_target_write_pc(),
+ write_pc_pid(), write_pc(), generic_target_read_sp(), read_sp(),
+ generic_target_write_sp(), write_sp(), generic_target_read_fp() and
+ read_fp(), will eventually be moved out of the reg-cache into
+ either frame.[hc] or to the multi-arch framework. The are not part
+ of the raw register cache. */
/* This routine is getting awfully cluttered with #if's. It's probably
time to turn this into READ_PC and define it in the tm.h file.
TARGET_READ_PC directly. (cagney). */
CORE_ADDR
-generic_target_read_pc (int pid)
+generic_target_read_pc (ptid_t ptid)
{
#ifdef PC_REGNUM
if (PC_REGNUM >= 0)
{
- CORE_ADDR pc_val = ADDR_BITS_REMOVE ((CORE_ADDR) read_register_pid (PC_REGNUM, pid));
+ CORE_ADDR pc_val = ADDR_BITS_REMOVE ((CORE_ADDR) read_register_pid (PC_REGNUM, ptid));
return pc_val;
}
#endif
}
CORE_ADDR
-read_pc_pid (int pid)
+read_pc_pid (ptid_t ptid)
{
- int saved_inferior_pid;
+ ptid_t saved_inferior_ptid;
CORE_ADDR pc_val;
- /* In case pid != inferior_pid. */
- saved_inferior_pid = inferior_pid;
- inferior_pid = pid;
+ /* In case ptid != inferior_ptid. */
+ saved_inferior_ptid = inferior_ptid;
+ inferior_ptid = ptid;
- pc_val = TARGET_READ_PC (pid);
+ pc_val = TARGET_READ_PC (ptid);
- inferior_pid = saved_inferior_pid;
+ inferior_ptid = saved_inferior_ptid;
return pc_val;
}
CORE_ADDR
read_pc (void)
{
- return read_pc_pid (inferior_pid);
+ return read_pc_pid (inferior_ptid);
}
void
-generic_target_write_pc (CORE_ADDR pc, int pid)
+generic_target_write_pc (CORE_ADDR pc, ptid_t ptid)
{
#ifdef PC_REGNUM
if (PC_REGNUM >= 0)
- write_register_pid (PC_REGNUM, pc, pid);
+ write_register_pid (PC_REGNUM, pc, ptid);
if (NPC_REGNUM >= 0)
- write_register_pid (NPC_REGNUM, pc + 4, pid);
- if (NNPC_REGNUM >= 0)
- write_register_pid (NNPC_REGNUM, pc + 8, pid);
+ write_register_pid (NPC_REGNUM, pc + 4, ptid);
#else
internal_error (__FILE__, __LINE__,
"generic_target_write_pc");
}
void
-write_pc_pid (CORE_ADDR pc, int pid)
+write_pc_pid (CORE_ADDR pc, ptid_t ptid)
{
- int saved_inferior_pid;
+ ptid_t saved_inferior_ptid;
- /* In case pid != inferior_pid. */
- saved_inferior_pid = inferior_pid;
- inferior_pid = pid;
+ /* In case ptid != inferior_ptid. */
+ saved_inferior_ptid = inferior_ptid;
+ inferior_ptid = ptid;
- TARGET_WRITE_PC (pc, pid);
+ TARGET_WRITE_PC (pc, ptid);
- inferior_pid = saved_inferior_pid;
+ inferior_ptid = saved_inferior_ptid;
}
void
write_pc (CORE_ADDR pc)
{
- write_pc_pid (pc, inferior_pid);
+ write_pc_pid (pc, inferior_ptid);
}
/* Cope with strage ways of getting to the stack and frame pointers */
return TARGET_READ_FP ();
}
-void
-generic_target_write_fp (CORE_ADDR val)
-{
-#ifdef FP_REGNUM
- if (FP_REGNUM >= 0)
- {
- write_register (FP_REGNUM, val);
- return;
- }
-#endif
- internal_error (__FILE__, __LINE__,
- "generic_target_write_fp");
-}
-
-void
-write_fp (CORE_ADDR val)
-{
- TARGET_WRITE_FP (val);
-}
-
/* ARGSUSED */
static void
reg_flush_command (char *command, int from_tty)
printf_filtered ("Register cache flushed.\n");
}
-
static void
build_regcache (void)
{
- /* We allocate some extra slop since we do a lot of memcpy's around
- `registers', and failing-soft is better than failing hard. */
- int sizeof_registers = REGISTER_BYTES + /* SLOP */ 256;
- int sizeof_register_valid =
- (NUM_REGS + NUM_PSEUDO_REGS) * sizeof (*register_valid);
+ int i;
+ int sizeof_register_valid;
+ /* Come up with the real size of the registers buffer. */
+ int sizeof_registers = REGISTER_BYTES; /* OK use. */
+ for (i = 0; i < NUM_REGS + NUM_PSEUDO_REGS; i++)
+ {
+ long regend;
+ /* Keep extending the buffer so that there is always enough
+ space for all registers. The comparison is necessary since
+ legacy code is free to put registers in random places in the
+ buffer separated by holes. Once REGISTER_BYTE() is killed
+ this can be greatly simplified. */
+ /* FIXME: cagney/2001-12-04: This code shouldn't need to use
+ REGISTER_BYTE(). Unfortunatly, legacy code likes to lay the
+ buffer out so that certain registers just happen to overlap.
+ Ulgh! New targets use gdbarch's register read/write and
+ entirely avoid this uglyness. */
+ regend = REGISTER_BYTE (i) + REGISTER_RAW_SIZE (i);
+ if (sizeof_registers < regend)
+ sizeof_registers = regend;
+ }
registers = xmalloc (sizeof_registers);
- memset (registers, 0, sizeof_registers);
+ sizeof_register_valid = ((NUM_REGS + NUM_PSEUDO_REGS)
+ * sizeof (*register_valid));
register_valid = xmalloc (sizeof_register_valid);
memset (register_valid, 0, sizeof_register_valid);
}
void
_initialize_regcache (void)
{
- build_regcache ();
-
register_gdbarch_swap (®isters, sizeof (registers), NULL);
register_gdbarch_swap (®ister_valid, sizeof (register_valid), NULL);
register_gdbarch_swap (NULL, 0, build_regcache);
add_com ("flushregs", class_maintenance, reg_flush_command,
"Force gdb to flush its register cache (maintainer command)");
+
+ /* Initialize the thread/process associated with the current set of
+ registers. For now, -1 is special, and means `no current process'. */
+ registers_ptid = pid_to_ptid (-1);
}