[PATCH 2/7] New regs_info for aarch32

[Yao Qi <qiyaoltc at gmail dot com>]

This patch adds a new regs_info regs_info_aarch32 for aarch32, which
can be used by both aarch64 and arm backend.

gdb/gdbserver:

2015-07-28  Yao Qi  <yao.qi@linaro.org>

	* configure.srv (srv_tgtobj): Add linux-aarch32-low.o.
	* linux-aarch32-low.c: New file.
	* linux-aarch32-low.h: New file.
	* linux-arm-low.c (arm_fill_gregset): Move it to
	linux-aarch32-low.c.
	(arm_store_gregset), arm_fill_vfpregset): Likewise.
	(arm_store_vfpregset): Likewise.
	(arm_arch_setup): Check if PTRACE_GETREGSET works.
	(regs_info): Rename to regs_info_arm.
	(arm_regs_info): Return regs_info_aarch32 if
	have_ptrace_getregset is 1 and target description isn't
	iwmmxt.
	(initialize_low_arch): Don't call
	init_registers_arm_with_vfpv2, init_registers_arm_with_vfpv3,
	and init_registers_arm_with_neon.  Call
	initialize_low_arch_aarch32 instead.
---
 gdb/gdbserver/configure.srv       |   1 +
 gdb/gdbserver/linux-aarch32-low.c | 141 ++++++++++++++++++++++++++++++++++++++
 gdb/gdbserver/linux-aarch32-low.h |  32 +++++++++
 gdb/gdbserver/linux-arm-low.c     | 108 +++++++----------------------
 4 files changed, 199 insertions(+), 83 deletions(-)
 create mode 100644 gdb/gdbserver/linux-aarch32-low.c
 create mode 100644 gdb/gdbserver/linux-aarch32-low.h

diff --git a/gdb/gdbserver/configure.srv b/gdb/gdbserver/configure.srv
index 9a04aac..1a8361a 100644
--- a/gdb/gdbserver/configure.srv
+++ b/gdb/gdbserver/configure.srv
@@ -62,6 +62,7 @@ case "${target}" in
 			srv_regobj="${srv_regobj} arm-with-vfpv3.o"
 			srv_regobj="${srv_regobj} arm-with-neon.o"
 			srv_tgtobj="$srv_linux_obj linux-arm-low.o"
+			srv_tgtobj="$srv_tgtobj linux-aarch32-low.o"
 			srv_xmlfiles="arm-with-iwmmxt.xml"
 			srv_xmlfiles="${srv_xmlfiles} arm-with-vfpv2.xml"
 			srv_xmlfiles="${srv_xmlfiles} arm-with-vfpv3.xml"
diff --git a/gdb/gdbserver/linux-aarch32-low.c b/gdb/gdbserver/linux-aarch32-low.c
new file mode 100644
index 0000000..0ca40c3
--- /dev/null
+++ b/gdb/gdbserver/linux-aarch32-low.c
@@ -0,0 +1,141 @@
+/* Copyright (C) 1995-2015 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 "arch/arm.h"
+#include "linux-low.h"
+#include "linux-aarch32-low.h"
+
+#include <sys/ptrace.h>
+/* Don't include elf.h if linux/elf.h got included by gdb_proc_service.h.
+   On Bionic elf.h and linux/elf.h have conflicting definitions.  */
+#ifndef ELFMAG0
+#include <elf.h>
+#endif
+
+/* Collect GP registers from REGCACHE to buffer BUF.  */
+
+void
+arm_fill_gregset (struct regcache *regcache, void *buf)
+{
+  int i;
+  uint32_t *regs = buf;
+
+  for (i = ARM_A1_REGNUM; i <= ARM_PC_REGNUM; i++)
+    collect_register (regcache, i, &regs[i]);
+
+  collect_register (regcache, ARM_PS_REGNUM, &regs[16]);
+}
+
+/* Supply GP registers contents, stored in BUF, to REGCACHE.  */
+
+void
+arm_store_gregset (struct regcache *regcache, const void *buf)
+{
+  int i;
+  char zerobuf[8];
+  const uint32_t *regs = buf;
+
+  memset (zerobuf, 0, 8);
+  for (i = ARM_A1_REGNUM; i <= ARM_PC_REGNUM; i++)
+    supply_register (regcache, i, &regs[i]);
+
+  for (; i < ARM_PS_REGNUM; i++)
+    supply_register (regcache, i, zerobuf);
+
+  supply_register (regcache, ARM_PS_REGNUM, &regs[16]);
+}
+
+/* Collect VFP registers from REGCACHE to buffer BUF.  */
+
+void
+arm_fill_vfpregset (struct regcache *regcache, void *buf)
+{
+  int i, num, base;
+
+  if (regcache->tdesc == tdesc_arm_with_neon
+      || regcache->tdesc == tdesc_arm_with_vfpv3)
+    num = 32;
+  else if (regcache->tdesc == tdesc_arm_with_vfpv2)
+    num = 16;
+  else
+    return;
+
+  base = find_regno (regcache->tdesc, "d0");
+  for (i = 0; i < num; i++)
+    collect_register (regcache, base + i, (char *) buf + i * 8);
+
+  collect_register_by_name (regcache, "fpscr", (char *) buf + 32 * 8);
+}
+
+/* Supply VFP registers contents, stored in BUF, to REGCACHE.  */
+
+void
+arm_store_vfpregset (struct regcache *regcache, const void *buf)
+{
+  int i, num, base;
+
+  if (regcache->tdesc == tdesc_arm_with_neon
+      || regcache->tdesc == tdesc_arm_with_vfpv3)
+    num = 32;
+  else if (regcache->tdesc == tdesc_arm_with_vfpv2)
+    num = 16;
+  else
+    return;
+
+  base = find_regno (regcache->tdesc, "d0");
+  for (i = 0; i < num; i++)
+    supply_register (regcache, base + i, (char *) buf + i * 8);
+
+  supply_register_by_name (regcache, "fpscr", (char *) buf + 32 * 8);
+}
+
+/* Register sets with using PTRACE_GETREGSET.  */
+
+static struct regset_info aarch32_regsets[] = {
+  { PTRACE_GETREGSET, PTRACE_SETREGSET, NT_PRSTATUS, 18 * 4,
+    GENERAL_REGS,
+    arm_fill_gregset, arm_store_gregset },
+  { PTRACE_GETREGSET, PTRACE_SETREGSET, NT_ARM_VFP, 32 * 8 + 4,
+    EXTENDED_REGS,
+    arm_fill_vfpregset, arm_store_vfpregset },
+  { 0, 0, 0, -1, -1, NULL, NULL }
+};
+
+static struct regsets_info aarch32_regsets_info =
+  {
+    aarch32_regsets, /* regsets */
+    0, /* num_regsets */
+    NULL, /* disabled_regsets */
+  };
+
+struct regs_info regs_info_aarch32 =
+  {
+    NULL, /* regset_bitmap */
+    NULL, /* usrregs */
+    &aarch32_regsets_info
+  };
+
+void
+initialize_low_arch_aarch32 (void)
+{
+  init_registers_arm_with_vfpv2 ();
+  init_registers_arm_with_vfpv3 ();
+  init_registers_arm_with_neon ();
+
+  initialize_regsets_info (&aarch32_regsets_info);
+}
diff --git a/gdb/gdbserver/linux-aarch32-low.h b/gdb/gdbserver/linux-aarch32-low.h
new file mode 100644
index 0000000..49bd5c3
--- /dev/null
+++ b/gdb/gdbserver/linux-aarch32-low.h
@@ -0,0 +1,32 @@
+/* Copyright (C) 1995-2015 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/>.  */
+
+extern struct regs_info regs_info_aarch32;
+
+void arm_fill_gregset (struct regcache *regcache, void *buf);
+void arm_store_gregset (struct regcache *regcache, const void *buf);
+void arm_fill_vfpregset (struct regcache *regcache, void *buf);
+void arm_store_vfpregset (struct regcache *regcache, const void *buf);
+
+void initialize_low_arch_aarch32 (void);
+
+void init_registers_arm_with_vfpv2 (void);
+extern const struct target_desc *tdesc_arm_with_vfpv2;
+void init_registers_arm_with_vfpv3 (void);
+extern const struct target_desc *tdesc_arm_with_vfpv3;
+void init_registers_arm_with_neon (void);
+extern const struct target_desc *tdesc_arm_with_neon;
diff --git a/gdb/gdbserver/linux-arm-low.c b/gdb/gdbserver/linux-arm-low.c
index 3c5956b..6aebd29 100644
--- a/gdb/gdbserver/linux-arm-low.c
+++ b/gdb/gdbserver/linux-arm-low.c
@@ -19,7 +19,9 @@
 #include "server.h"
 #include "linux-low.h"
 #include "arch/arm.h"
+#include "linux-aarch32-low.h"
 
+#include <sys/uio.h>
 /* Don't include elf.h if linux/elf.h got included by gdb_proc_service.h.
    On Bionic elf.h and linux/elf.h have conflicting definitions.  */
 #ifndef ELFMAG0
@@ -35,15 +37,6 @@ extern const struct target_desc *tdesc_arm;
 void init_registers_arm_with_iwmmxt (void);
 extern const struct target_desc *tdesc_arm_with_iwmmxt;
 
-void init_registers_arm_with_vfpv2 (void);
-extern const struct target_desc *tdesc_arm_with_vfpv2;
-
-void init_registers_arm_with_vfpv3 (void);
-extern const struct target_desc *tdesc_arm_with_vfpv3;
-
-void init_registers_arm_with_neon (void);
-extern const struct target_desc *tdesc_arm_with_neon;
-
 #ifndef PTRACE_GET_THREAD_AREA
 #define PTRACE_GET_THREAD_AREA 22
 #endif
@@ -150,35 +143,6 @@ arm_cannot_fetch_register (int regno)
 }
 
 static void
-arm_fill_gregset (struct regcache *regcache, void *buf)
-{
-  int i;
-  uint32_t *regs = buf;
-
-  for (i = ARM_A1_REGNUM; i <= ARM_PC_REGNUM; i++)
-    collect_register (regcache, i, &regs[i]);
-
-  collect_register (regcache, ARM_PS_REGNUM, &regs[16]);
-}
-
-static void
-arm_store_gregset (struct regcache *regcache, const void *buf)
-{
-  int i;
-  char zerobuf[8];
-  const uint32_t *regs = buf;
-
-  memset (zerobuf, 0, 8);
-  for (i = ARM_A1_REGNUM; i <= ARM_PC_REGNUM; i++)
-    supply_register (regcache, i, &regs[i]);
-
-  for (; i < ARM_PS_REGNUM; i++)
-    supply_register (regcache, i, zerobuf);
-
-  supply_register (regcache, ARM_PS_REGNUM, &regs[16]);
-}
-
-static void
 arm_fill_wmmxregset (struct regcache *regcache, void *buf)
 {
   int i;
@@ -212,46 +176,6 @@ arm_store_wmmxregset (struct regcache *regcache, const void *buf)
 		     (char *) buf + 16 * 8 + i * 4);
 }
 
-static void
-arm_fill_vfpregset (struct regcache *regcache, void *buf)
-{
-  int i, num, base;
-
-  if (regcache->tdesc == tdesc_arm_with_neon
-      || regcache->tdesc == tdesc_arm_with_vfpv3)
-    num = 32;
-  else if (regcache->tdesc == tdesc_arm_with_vfpv2)
-    num = 16;
-  else
-    return;
-
-  base = find_regno (regcache->tdesc, "d0");
-  for (i = 0; i < num; i++)
-    collect_register (regcache, base + i, (char *) buf + i * 8);
-
-  collect_register_by_name (regcache, "fpscr", (char *) buf + 32 * 8);
-}
-
-static void
-arm_store_vfpregset (struct regcache *regcache, const void *buf)
-{
-  int i, num, base;
-
-  if (regcache->tdesc == tdesc_arm_with_neon
-      || regcache->tdesc == tdesc_arm_with_vfpv3)
-    num = 32;
-  else if (regcache->tdesc == tdesc_arm_with_vfpv2)
-    num = 16;
-  else
-    return;
-
-  base = find_regno (regcache->tdesc, "d0");
-  for (i = 0; i < num; i++)
-    supply_register (regcache, base + i, (char *) buf + i * 8);
-
-  supply_register_by_name (regcache, "fpscr", (char *) buf + 32 * 8);
-}
-
 extern int debug_threads;
 
 static CORE_ADDR
@@ -888,9 +812,24 @@ arm_read_description (void)
 static void
 arm_arch_setup (void)
 {
+  int tid = lwpid_of (current_thread);
+  int gpregs[18];
+  struct iovec iov;
+
   current_process ()->tdesc = arm_read_description ();
+
+  iov.iov_base = gpregs;
+  iov.iov_len = sizeof (gpregs);
+
+  /* Check if PTRACE_GETREGSET works.  */
+  if (ptrace (PTRACE_GETREGSET, tid, NT_PRSTATUS, &iov) == 0)
+    have_ptrace_getregset = 1;
+  else
+    have_ptrace_getregset = 0;
 }
 
+/* Register sets without using PTRACE_GETREGSET.  */
+
 static struct regset_info arm_regsets[] = {
   { PTRACE_GETREGS, PTRACE_SETREGS, 0, 18 * 4,
     GENERAL_REGS,
@@ -917,7 +856,7 @@ static struct usrregs_info arm_usrregs_info =
     arm_regmap,
   };
 
-static struct regs_info regs_info =
+static struct regs_info regs_info_arm =
   {
     NULL, /* regset_bitmap */
     &arm_usrregs_info,
@@ -927,7 +866,11 @@ static struct regs_info regs_info =
 static const struct regs_info *
 arm_regs_info (void)
 {
-  return &regs_info;
+  if (have_ptrace_getregset == 1
+      && current_process ()->tdesc != tdesc_arm_with_iwmmxt)
+    return &regs_info_aarch32;
+  else
+    return &regs_info_arm;
 }
 
 struct linux_target_ops the_low_target = {
@@ -973,9 +916,8 @@ initialize_low_arch (void)
   /* Initialize the Linux target descriptions.  */
   init_registers_arm ();
   init_registers_arm_with_iwmmxt ();
-  init_registers_arm_with_vfpv2 ();
-  init_registers_arm_with_vfpv3 ();
-  init_registers_arm_with_neon ();
+
+  initialize_low_arch_aarch32 ();
 
   initialize_regsets_info (&arm_regsets_info);
 }
-- 
1.9.1