[PATCH 09/16] btrace, linux: add linux native btrace target ops

[markus dot t dot metzger at intel dot com]

From: Markus Metzger <markus.t.metzger@intel.com>

Implement btrace target ops for linux native based on the common linux btrace
support.

We use a separate file for this to allow sharing between multiple targets
(i.e. i386 and x86_64) and to avoid having to guard this for targets that do not
support branch tracing.

2012-05-23 Markus Metzger <markus.t.metzger@intel.com>

  gdb/
  * linux-nat-btrace.h: New file
  * linux-nat-btrace.c: New file


---
 gdb/linux-nat-btrace.c |   86 ++++++++++++++++++++++++++++++++++++++++++++++++
 gdb/linux-nat-btrace.h |   28 +++++++++++++++
 2 files changed, 114 insertions(+), 0 deletions(-)
 create mode 100644 gdb/linux-nat-btrace.c
 create mode 100644 gdb/linux-nat-btrace.h

diff --git a/gdb/linux-nat-btrace.c b/gdb/linux-nat-btrace.c
new file mode 100644
index 0000000..f69fc6f
--- /dev/null
+++ b/gdb/linux-nat-btrace.c
@@ -0,0 +1,86 @@
+/* Branch trace support for GDB, the GNU debugger.
+
+   Copyright (C) 2012 Free Software Foundation, Inc.
+
+   Contributed by Intel Corp. <markus.t.metzger@intel.com>.
+
+   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 "linux-nat-btrace.h"
+#include "linux-btrace.h"
+#include "btrace.h"
+#include "target.h"
+#include "gdbarch.h"
+#include "arch-utils.h"
+#include <errno.h>
+
+static int
+linux_nat_push_btrace_record (struct linux_btrace_block *raw, void *arg)
+{
+  VEC (btrace_block_s) **btrace = arg;
+  struct btrace_block *block;
+
+  if (!raw)
+    return EINVAL;
+
+  if (!btrace)
+    return EINVAL;
+
+  block = VEC_safe_push (btrace_block_s, *btrace, NULL);
+  if (!block)
+      return ENOMEM;
+
+  block->begin = raw->begin;
+  block->end   = raw->end;
+
+  return 0;
+}
+
+static VEC (btrace_block_s) *
+linux_nat_read_btrace (struct btrace_target_info *tinfo)
+{
+  VEC (btrace_block_s) *btrace = NULL;
+  int errcode;
+
+  if (!tinfo)
+    {
+      errno = EINVAL;
+      return NULL;
+    }
+  if (!tinfo->ptr_bits)
+    {
+      struct gdbarch *gdbarch = get_current_arch ();
+      if (gdbarch)
+        tinfo->ptr_bits = gdbarch_ptr_bit (gdbarch);
+    }
+
+  errcode = linux_read_btrace (tinfo, linux_nat_push_btrace_record, &btrace);
+  if (errcode)
+    warning (_("error while reading branch trace data: %s. "
+               "trace might be incomplete."), safe_strerror (errcode));
+
+  return btrace;
+}
+
+void
+linux_nat_add_btrace_ops (struct target_ops *t)
+{
+  t->to_supports_btrace = linux_supports_btrace;
+  t->to_enable_btrace = linux_enable_btrace;
+  t->to_disable_btrace = linux_disable_btrace;
+  t->to_btrace_has_changed = linux_btrace_has_changed;
+  t->to_read_btrace = linux_nat_read_btrace;
+}
diff --git a/gdb/linux-nat-btrace.h b/gdb/linux-nat-btrace.h
new file mode 100644
index 0000000..cbe9c89
--- /dev/null
+++ b/gdb/linux-nat-btrace.h
@@ -0,0 +1,28 @@
+/* Branch trace support for GDB, the GNU debugger.
+
+   Copyright (C) 2012 Free Software Foundation, Inc.
+
+   Contributed by Intel Corp. <markus.t.metzger@intel.com>.
+
+   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/>.  */
+
+#ifndef LINUX_NAT_BTRACE_H
+#define LINUX_NAT_BTRACE_H
+
+struct target_ops;
+extern void linux_nat_add_btrace_ops (struct target_ops *);
+
+#endif /* LINUX_NAT_BTRACE_H */
-- 
1.7.1