gdb: xtensa: use remote target register numer...

...instead of the sequential number defined in xtensa-config.c
when retrieving registers from remote target, as the remote
probe maps registers to their target numbers.

Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>

Author: dcpleung

gdb/configure

@@ -976,6 +976,7 @@ with_babeltrace
 with_libbabeltrace_prefix
 with_libbabeltrace_type
 enable_libctf
+enable_xtensa_use_target_regnum
 enable_unit_tests
 '
       ac_precious_vars='build_alias
@@ -1662,6 +1663,8 @@ Optional Features:
   --enable-libbacktrace   use libbacktrace to write a backtrace after a fatal
                           signal.
   --enable-libctf         Handle .ctf type-info sections [default=yes]
+  --enable-xtensa-use-target-regnum
+                          Use remote target register numbers (Xtensa target)
   --enable-unit-tests     Enable the inclusion of unit tests when compiling
                           GDB
 
@@ -11500,7 +11503,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11503 "configure"
+#line 11506 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11606,7 +11609,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11609 "configure"
+#line 11612 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -33636,6 +33639,23 @@ fi
 # If nativefile (NAT_FILE) is not set in configure.nat, we link to an
 # empty version.
 
+# Xtensa to use target register number
+# Check whether --enable-xtensa-use-target-regnum was given.
+if test "${enable_xtensa_use_target_regnum+set}" = set; then :
+  enableval=$enable_xtensa_use_target_regnum; case $enableval in
+    yes | no)
+      enable_xtensa_use_target_regnum=$enableval ;;
+    *)
+      as_fn_error $? "bad value $enableval for --enable-xtensa-use-target-regnum" "$LINENO" 5 ;;
+  esac
+else
+  enable_xtensa_use_target_regnum=no
+fi
+
+if test x"$enable_xtensa_use_target_regnum" = xyes; then
+  CPPFLAGS="$CPPFLAGS -DXTENSA_USE_TGT_REGNUM"
+fi
+
 NM_H=
 rm -f nm.h
 if test "${nativefile}" != ""; then

gdb/configure.ac

@@ -2230,6 +2230,20 @@ AC_SUBST(CTF_DEPS)
 # If nativefile (NAT_FILE) is not set in configure.nat, we link to an
 # empty version.
 
+# Xtensa to use target register number
+AC_ARG_ENABLE(xtensa-use-target-regnum,
+AS_HELP_STRING([--enable-xtensa-use-target-regnum], [Use remote target register numbers (Xtensa target)]),
+  [case $enableval in
+    yes | no)
+      enable_xtensa_use_target_regnum=$enableval ;;
+    *)
+      AC_MSG_ERROR([bad value $enableval for --enable-xtensa-use-target-regnum]) ;;
+  esac],
+  [enable_xtensa_use_target_regnum=no])
+if test x"$enable_xtensa_use_target_regnum" = xyes; then
+  CPPFLAGS="$CPPFLAGS -DXTENSA_USE_TGT_REGNUM"
+fi
+
 NM_H=
 rm -f nm.h
 if test "${nativefile}" != ""; then

gdb/xtensa-tdep.c

@@ -3146,6 +3146,21 @@ xtensa_derive_tdep (xtensa_gdbarch_tdep *tdep)
   tdep->max_register_virtual_size = max_size;
 }
 
+#ifdef XTENSA_USE_TGT_REGNUM
+static int
+xtensa_remote_register_number (struct gdbarch *gdbarch, int regnum)
+{
+  xtensa_gdbarch_tdep *tdep = gdbarch_tdep<xtensa_gdbarch_tdep> (gdbarch);
+
+  /* Return the name stored in the register map.  */
+  if (regnum >= 0 && regnum < gdbarch_num_cooked_regs (gdbarch))
+    return tdep->regmap[regnum].target_number;
+
+  internal_error (__FILE__, __LINE__, _("invalid register %d"), regnum);
+  return regnum;
+}
+#endif
+
 /* Module "constructor" function.  */
 
 extern xtensa_register_t xtensa_rmap[];
@@ -3194,6 +3209,10 @@ xtensa_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
   set_gdbarch_register_name (gdbarch, xtensa_register_name);
   set_gdbarch_register_type (gdbarch, xtensa_register_type);
 
+#ifdef XTENSA_USE_TGT_REGNUM
+  set_gdbarch_remote_register_number (gdbarch, xtensa_remote_register_number);
+#endif
+
   /* To call functions from GDB using dummy frame.  */
   set_gdbarch_push_dummy_call (gdbarch, xtensa_push_dummy_call);