1 files changed, 528 insertions, 0 deletions
diff --git a/gdbserver/regcache.c b/gdbserver/regcache.c
new file mode 100644
index 0000000..f634633
--- /dev/null
+++ b/gdbserver/regcache.c
@@ -0,0 +1,528 @@
+/* Register support routines for the remote server for GDB.
+   Copyright (C) 2001-2020 Free Software Foundation, Inc.
+
+   This file is part of GDB.
+
+   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 3 of the License, or
+   (at your option) any later version.
+
+   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, see <http://www.gnu.org/licenses/>.  */
+
+#include "server.h"
+#include "regdef.h"
+#include "gdbthread.h"
+#include "tdesc.h"
+#include "gdbsupport/rsp-low.h"
+#ifndef IN_PROCESS_AGENT
+
+struct regcache *
+get_thread_regcache (struct thread_info *thread, int fetch)
+{
+  struct regcache *regcache;
+
+  regcache = thread_regcache_data (thread);
+
+  /* Threads' regcaches are created lazily, because biarch targets add
+     the main thread/lwp before seeing it stop for the first time, and
+     it is only after the target sees the thread stop for the first
+     time that the target has a chance of determining the process's
+     architecture.  IOW, when we first add the process's main thread
+     we don't know which architecture/tdesc its regcache should
+     have.  */
+  if (regcache == NULL)
+    {
+      struct process_info *proc = get_thread_process (thread);
+
+      gdb_assert (proc->tdesc != NULL);
+
+      regcache = new_register_cache (proc->tdesc);
+      set_thread_regcache_data (thread, regcache);
+    }
+
+  if (fetch && regcache->registers_valid == 0)
+    {
+      struct thread_info *saved_thread = current_thread;
+
+      current_thread = thread;
+      /* Invalidate all registers, to prevent stale left-overs.  */
+      memset (regcache->register_status, REG_UNAVAILABLE,
+	      regcache->tdesc->reg_defs.size ());
+      fetch_inferior_registers (regcache, -1);
+      current_thread = saved_thread;
+      regcache->registers_valid = 1;
+    }
+
+  return regcache;
+}
+
+/* See gdbsupport/common-regcache.h.  */
+
+struct regcache *
+get_thread_regcache_for_ptid (ptid_t ptid)
+{
+  return get_thread_regcache (find_thread_ptid (ptid), 1);
+}
+
+void
+regcache_invalidate_thread (struct thread_info *thread)
+{
+  struct regcache *regcache;
+
+  regcache = thread_regcache_data (thread);
+
+  if (regcache == NULL)
+    return;
+
+  if (regcache->registers_valid)
+    {
+      struct thread_info *saved_thread = current_thread;
+
+      current_thread = thread;
+      store_inferior_registers (regcache, -1);
+      current_thread = saved_thread;
+    }
+
+  regcache->registers_valid = 0;
+}
+
+/* See regcache.h.  */
+
+void
+regcache_invalidate_pid (int pid)
+{
+  /* Only invalidate the regcaches of threads of this process.  */
+  for_each_thread (pid, regcache_invalidate_thread);
+}
+
+/* See regcache.h.  */
+
+void
+regcache_invalidate (void)
+{
+  /* Only update the threads of the current process.  */
+  int pid = current_thread->id.pid ();
+
+  regcache_invalidate_pid (pid);
+}
+
+#endif
+
+struct regcache *
+init_register_cache (struct regcache *regcache,
+		     const struct target_desc *tdesc,
+		     unsigned char *regbuf)
+{
+  if (regbuf == NULL)
+    {
+#ifndef IN_PROCESS_AGENT
+      /* Make sure to zero-initialize the register cache when it is
+	 created, in case there are registers the target never
+	 fetches.  This way they'll read as zero instead of
+	 garbage.  */
+      regcache->tdesc = tdesc;
+      regcache->registers
+	= (unsigned char *) xcalloc (1, tdesc->registers_size);
+      regcache->registers_owned = 1;
+      regcache->register_status
+	= (unsigned char *) xmalloc (tdesc->reg_defs.size ());
+      memset ((void *) regcache->register_status, REG_UNAVAILABLE,
+	      tdesc->reg_defs.size ());
+#else
+      gdb_assert_not_reached ("can't allocate memory from the heap");
+#endif
+    }
+  else
+    {
+      regcache->tdesc = tdesc;
+      regcache->registers = regbuf;
+      regcache->registers_owned = 0;
+#ifndef IN_PROCESS_AGENT
+      regcache->register_status = NULL;
+#endif
+    }
+
+  regcache->registers_valid = 0;
+
+  return regcache;
+}
+
+#ifndef IN_PROCESS_AGENT
+
+struct regcache *
+new_register_cache (const struct target_desc *tdesc)
+{
+  struct regcache *regcache = new struct regcache;
+
+  gdb_assert (tdesc->registers_size != 0);
+
+  return init_register_cache (regcache, tdesc, NULL);
+}
+
+void
+free_register_cache (struct regcache *regcache)
+{
+  if (regcache)
+    {
+      if (regcache->registers_owned)
+	free (regcache->registers);
+      free (regcache->register_status);
+      delete regcache;
+    }
+}
+
+#endif
+
+void
+regcache_cpy (struct regcache *dst, struct regcache *src)
+{
+  gdb_assert (src != NULL && dst != NULL);
+  gdb_assert (src->tdesc == dst->tdesc);
+  gdb_assert (src != dst);
+
+  memcpy (dst->registers, src->registers, src->tdesc->registers_size);
+#ifndef IN_PROCESS_AGENT
+  if (dst->register_status != NULL && src->register_status != NULL)
+    memcpy (dst->register_status, src->register_status,
+	    src->tdesc->reg_defs.size ());
+#endif
+  dst->registers_valid = src->registers_valid;
+}
+
+/* Return a reference to the description of register N.  */
+
+static const struct reg &
+find_register_by_number (const struct target_desc *tdesc, int n)
+{
+  return tdesc->reg_defs[n];
+}
+
+#ifndef IN_PROCESS_AGENT
+
+void
+registers_to_string (struct regcache *regcache, char *buf)
+{
+  unsigned char *registers = regcache->registers;
+  const struct target_desc *tdesc = regcache->tdesc;
+
+  for (int i = 0; i < tdesc->reg_defs.size (); ++i)
+    {
+      if (regcache->register_status[i] == REG_VALID)
+	{
+	  bin2hex (registers, buf, register_size (tdesc, i));
+	  buf += register_size (tdesc, i) * 2;
+	}
+      else
+	{
+	  memset (buf, 'x', register_size (tdesc, i) * 2);
+	  buf += register_size (tdesc, i) * 2;
+	}
+      registers += register_size (tdesc, i);
+    }
+  *buf = '\0';
+}
+
+void
+registers_from_string (struct regcache *regcache, char *buf)
+{
+  int len = strlen (buf);
+  unsigned char *registers = regcache->registers;
+  const struct target_desc *tdesc = regcache->tdesc;
+
+  if (len != tdesc->registers_size * 2)
+    {
+      warning ("Wrong sized register packet (expected %d bytes, got %d)",
+	       2 * tdesc->registers_size, len);
+      if (len > tdesc->registers_size * 2)
+	len = tdesc->registers_size * 2;
+    }
+  hex2bin (buf, registers, len / 2);
+}
+
+int
+find_regno (const struct target_desc *tdesc, const char *name)
+{
+  for (int i = 0; i < tdesc->reg_defs.size (); ++i)
+    {
+      if (strcmp (name, find_register_by_number (tdesc, i).name) == 0)
+	return i;
+    }
+  internal_error (__FILE__, __LINE__, "Unknown register %s requested",
+		  name);
+}
+
+static void
+free_register_cache_thread (struct thread_info *thread)
+{
+  struct regcache *regcache = thread_regcache_data (thread);
+
+  if (regcache != NULL)
+    {
+      regcache_invalidate_thread (thread);
+      free_register_cache (regcache);
+      set_thread_regcache_data (thread, NULL);
+    }
+}
+
+void
+regcache_release (void)
+{
+  /* Flush and release all pre-existing register caches.  */
+  for_each_thread (free_register_cache_thread);
+}
+#endif
+
+int
+register_cache_size (const struct target_desc *tdesc)
+{
+  return tdesc->registers_size;
+}
+
+int
+register_size (const struct target_desc *tdesc, int n)
+{
+  return find_register_by_number (tdesc, n).size / 8;
+}
+
+/* See gdbsupport/common-regcache.h.  */
+
+int
+regcache_register_size (const struct regcache *regcache, int n)
+{
+  return register_size (regcache->tdesc, n);
+}
+
+static unsigned char *
+register_data (const struct regcache *regcache, int n, int fetch)
+{
+  return (regcache->registers
+	  + find_register_by_number (regcache->tdesc, n).offset / 8);
+}
+
+void
+supply_register (struct regcache *regcache, int n, const void *buf)
+{
+  return regcache->raw_supply (n, buf);
+}
+
+/* See gdbsupport/common-regcache.h.  */
+
+void
+regcache::raw_supply (int n, const void *buf)
+{
+  if (buf)
+    {
+      memcpy (register_data (this, n, 0), buf, register_size (tdesc, n));
+#ifndef IN_PROCESS_AGENT
+      if (register_status != NULL)
+	register_status[n] = REG_VALID;
+#endif
+    }
+  else
+    {
+      memset (register_data (this, n, 0), 0, register_size (tdesc, n));
+#ifndef IN_PROCESS_AGENT
+      if (register_status != NULL)
+	register_status[n] = REG_UNAVAILABLE;
+#endif
+    }
+}
+
+/* Supply register N with value zero to REGCACHE.  */
+
+void
+supply_register_zeroed (struct regcache *regcache, int n)
+{
+  memset (register_data (regcache, n, 0), 0,
+	  register_size (regcache->tdesc, n));
+#ifndef IN_PROCESS_AGENT
+  if (regcache->register_status != NULL)
+    regcache->register_status[n] = REG_VALID;
+#endif
+}
+
+#ifndef IN_PROCESS_AGENT
+
+/* Supply register called NAME with value zero to REGCACHE.  */
+
+void
+supply_register_by_name_zeroed (struct regcache *regcache,
+				const char *name)
+{
+  supply_register_zeroed (regcache, find_regno (regcache->tdesc, name));
+}
+
+#endif
+
+/* Supply the whole register set whose contents are stored in BUF, to
+   REGCACHE.  If BUF is NULL, all the registers' values are recorded
+   as unavailable.  */
+
+void
+supply_regblock (struct regcache *regcache, const void *buf)
+{
+  if (buf)
+    {
+      const struct target_desc *tdesc = regcache->tdesc;
+
+      memcpy (regcache->registers, buf, tdesc->registers_size);
+#ifndef IN_PROCESS_AGENT
+      {
+	int i;
+
+	for (i = 0; i < tdesc->reg_defs.size (); i++)
+	  regcache->register_status[i] = REG_VALID;
+      }
+#endif
+    }
+  else
+    {
+      const struct target_desc *tdesc = regcache->tdesc;
+
+      memset (regcache->registers, 0, tdesc->registers_size);
+#ifndef IN_PROCESS_AGENT
+      {
+	int i;
+
+	for (i = 0; i < tdesc->reg_defs.size (); i++)
+	  regcache->register_status[i] = REG_UNAVAILABLE;
+      }
+#endif
+    }
+}
+
+#ifndef IN_PROCESS_AGENT
+
+void
+supply_register_by_name (struct regcache *regcache,
+			 const char *name, const void *buf)
+{
+  supply_register (regcache, find_regno (regcache->tdesc, name), buf);
+}
+
+#endif
+
+void
+collect_register (struct regcache *regcache, int n, void *buf)
+{
+  regcache->raw_collect (n, buf);
+}
+
+/* See gdbsupport/common-regcache.h.  */
+
+void
+regcache::raw_collect (int n, void *buf) const
+{
+  memcpy (buf, register_data (this, n, 1), register_size (tdesc, n));
+}
+
+enum register_status
+regcache_raw_read_unsigned (struct regcache *regcache, int regnum,
+			    ULONGEST *val)
+{
+  int size;
+
+  gdb_assert (regcache != NULL);
+  gdb_assert (regnum >= 0
+	      && regnum < regcache->tdesc->reg_defs.size ());
+
+  size = register_size (regcache->tdesc, regnum);
+
+  if (size > (int) sizeof (ULONGEST))
+    error (_("That operation is not available on integers of more than"
+            "%d bytes."),
+          (int) sizeof (ULONGEST));
+
+  *val = 0;
+  collect_register (regcache, regnum, val);
+
+  return REG_VALID;
+}
+
+#ifndef IN_PROCESS_AGENT
+
+/* See regcache.h.  */
+
+ULONGEST
+regcache_raw_get_unsigned_by_name (struct regcache *regcache,
+				   const char *name)
+{
+  return regcache_raw_get_unsigned (regcache,
+				    find_regno (regcache->tdesc, name));
+}
+
+void
+collect_register_as_string (struct regcache *regcache, int n, char *buf)
+{
+  bin2hex (register_data (regcache, n, 1), buf,
+	   register_size (regcache->tdesc, n));
+}
+
+void
+collect_register_by_name (struct regcache *regcache,
+			  const char *name, void *buf)
+{
+  collect_register (regcache, find_regno (regcache->tdesc, name), buf);
+}
+
+/* Special handling for register PC.  */
+
+CORE_ADDR
+regcache_read_pc (struct regcache *regcache)
+{
+  CORE_ADDR pc_val;
+
+  if (the_target->read_pc)
+    pc_val = the_target->read_pc (regcache);
+  else
+    internal_error (__FILE__, __LINE__,
+		    "regcache_read_pc: Unable to find PC");
+
+  return pc_val;
+}
+
+void
+regcache_write_pc (struct regcache *regcache, CORE_ADDR pc)
+{
+  if (the_target->write_pc)
+    the_target->write_pc (regcache, pc);
+  else
+    internal_error (__FILE__, __LINE__,
+		    "regcache_write_pc: Unable to update PC");
+}
+
+#endif
+
+/* See gdbsupport/common-regcache.h.  */
+
+enum register_status
+regcache::get_register_status (int regnum) const
+{
+#ifndef IN_PROCESS_AGENT
+  gdb_assert (regnum >= 0 && regnum < tdesc->reg_defs.size ());
+  return (enum register_status) (register_status[regnum]);
+#else
+  return REG_VALID;
+#endif
+}
+
+/* See gdbsupport/common-regcache.h.  */
+
+bool
+regcache::raw_compare (int regnum, const void *buf, int offset) const
+{
+  gdb_assert (buf != NULL);
+
+  const unsigned char *regbuf = register_data (this, regnum, 1);
+  int size = register_size (tdesc, regnum);
+  gdb_assert (size >= offset);
+
+  return (memcmp (buf, regbuf + offset, size - offset) == 0);
+}