[PATCH] Fix display of structures/bitfields in register description.

[Walfred Tedeschi <walfred dot tedeschi at intel dot com>]

Add support for displaying structures and bitfields for registers when
executing the "maint print c-tdesc". Command is also used when
converting the xml target description file into c file.

Example of the behaviour is given below reporting a snipet of the xml file
and a snippet of the c code generated.

XML file contains:
...
    <union id="vecint">
      <field name="v4" type="v4int8"/>
      <field name="v2" type="v2int16"/>
    </union>

    <struct id="struct1">
      <field name="v4" type="v4int8"/>
      <field name="v2" type="v2int16"/>
    </struct>

    <struct id="struct2" size="8">
      <field name="f1" start="0" end="34"/>
      <field name="f2" start="63" end="63"/>
    </struct>
...

Setting this xml file as target description file and
issuing the maintenance print c-tdesc the following output
is obtained:

  feature = tdesc_create_feature (result, "extra");
  field_type = tdesc_named_type (feature, "int8");
  tdesc_create_vector (feature, "v4int8", field_type, 4);

  field_type = tdesc_named_type (feature, "int16");
  tdesc_create_vector (feature, "v2int16", field_type, 2);

  type = tdesc_create_union (feature, "vecint");
  field_type = tdesc_named_type (feature, "v4int8");
  tdesc_add_field (type, "v4", field_type);
  field_type = tdesc_named_type (feature, "v2int16");
  tdesc_add_field (type, "v2", field_type);

C output is not supported type "struct1".

This is finally the issue.

2013-03-27  Walfred Tedeschi  <walfred.tedeschi@intel.com>

        * target-descriptions.c (maint_print_c_tdesc_cmd):
        Add case to parse structures as register types and
        bitfields.

testsuite/gdb.xml/

	* maint_print_struct.exp: New file.
	* maint_print_struct.xml: New file.

Signed-off-by: Walfred Tedeschi <walfred.tedeschi@intel.com>
---
 gdb/target-descriptions.c                    |   30 +++++++++++++++++++++
 gdb/testsuite/gdb.xml/maint_print_struct.exp |   37 ++++++++++++++++++++++++++
 gdb/testsuite/gdb.xml/maint_print_struct.xml |   26 ++++++++++++++++++
 3 files changed, 93 insertions(+)
 create mode 100644 gdb/testsuite/gdb.xml/maint_print_struct.exp
 create mode 100644 gdb/testsuite/gdb.xml/maint_print_struct.xml

diff --git a/gdb/target-descriptions.c b/gdb/target-descriptions.c
index 95980c5..88a08ad 100644
--- a/gdb/target-descriptions.c
+++ b/gdb/target-descriptions.c
@@ -1746,6 +1746,36 @@ feature = tdesc_create_feature (result, \"%s\");\n",
 		("  tdesc_create_vector (feature, \"%s\", field_type, %d);\n",
 		 type->name, type->u.v.count);
 	      break;
+	    case TDESC_TYPE_STRUCT:
+	      printf_unfiltered
+		("  type = tdesc_create_struct (feature, \"%s\");\n",
+		 type->name);
+	      if (type->u.u.size != 0)
+		printf_unfiltered
+		  ("  tdesc_set_struct_size (type, %s);\n",
+		   plongest (type->u.u.size));
+	      for (ix3 = 0;
+		   VEC_iterate (tdesc_type_field, type->u.u.fields, ix3, f);
+		   ix3++)
+		{
+		  /* Going first for implicitly sized types, else part handles
+		     bitfields.  As reported on xml-tdesc.c implicitly sized types
+		     cannot contain a bitfield.  */
+		  if (f->start == 0 && f->end == 0)
+		    {
+		      printf_unfiltered
+			("  field_type = tdesc_named_type (feature, \"%s\");\n",
+			 f->type->name);
+		      printf_unfiltered
+			("  tdesc_add_field (type, \"%s\", field_type);\n",
+			 f->name);
+		    }
+		  else
+		    printf_unfiltered
+		      ("  tdesc_add_bitfield (type, \"%s\", %d, %d);\n",
+		       f->name, f->start, f->end);
+		}
+	      break;
 	    case TDESC_TYPE_UNION:
 	      printf_unfiltered
 		("  type = tdesc_create_union (feature, \"%s\");\n",
diff --git a/gdb/testsuite/gdb.xml/maint_print_struct.exp b/gdb/testsuite/gdb.xml/maint_print_struct.exp
new file mode 100644
index 0000000..f444451
--- /dev/null
+++ b/gdb/testsuite/gdb.xml/maint_print_struct.exp
@@ -0,0 +1,37 @@
+# This testcase is part of GDB, the GNU debugger.
+#
+# Copyright 2013 Free Software Foundation, Inc.
+#
+# Contributed by Intel Corp. <walfred.tedeschi@intel.com>
+#
+# 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/>.
+
+if {[gdb_skip_xml_test]} {
+    unsupported "maint_print_struct.exp"
+    return -1
+}
+
+gdb_start
+global srcdir
+global subdir
+
+# Required registers are not present so it is expected a warning.
+#
+gdb_test "set tdesc filename $srcdir/$subdir/maint_print_struct.xml" "
+warning:.*" "setting a new tdesc having only a structure"
+
+gdb_test "maint print c-tdesc" "
+.*tdesc_create_reg \\(feature, \"bad_reg1\", \[0-9\]+, 1, NULL, 128, \"two_fielded\"\\);\r
+.*tdesc_create_reg \\(feature, \"bad_reg2\", \[0-9\]+, 1, NULL, 64, \"bitfield\"\\);\r
+.*" "printing tdesc with a structure and a bitfield"
diff --git a/gdb/testsuite/gdb.xml/maint_print_struct.xml b/gdb/testsuite/gdb.xml/maint_print_struct.xml
new file mode 100644
index 0000000..dab71fa
--- /dev/null
+++ b/gdb/testsuite/gdb.xml/maint_print_struct.xml
@@ -0,0 +1,26 @@
+<?xml version="1.0"?>
+<!-- Copyright (C) 2013 Free Software Foundation, Inc.
+
+     Copying and distribution of this file, with or without modification,
+     are permitted in any medium without royalty provided the copyright
+     notice and this notice are preserved.  -->
+
+<!DOCTYPE feature SYSTEM "gdb-target.dtd">
+<target>
+<feature name="test">
+
+  <struct id="two_fielded">
+       <field name="field1" type="data_ptr"/>
+       <field name="field2" type="data_ptr"/>
+  </struct>
+
+  <struct id="bitfield" size="8">
+    <field name="field1" start="24" end="63"/>
+    <field name="field2" start="16" end="24"/>
+  </struct>
+
+  <reg name="bad_reg1" bitsize="128" type="two_fielded"/>
+  <reg name="bad_reg2" bitsize="64"  type="bitfield"/>
+</feature>
+</target>
+
-- 
1.7.10.4