gdbstub: Add num_regs member to GDBFeature

Currently the number of registers exposed to GDB is written as magic
numbers in code. Derive the number of registers GDB actually see from
XML files to replace the magic numbers in code later.

Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20231025093128.33116-2-akihiko.odaki@daynix.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20231106185112.2755262-9-alex.bennee@linaro.org>

diff --git a/include/exec/gdbstub.h b/include/exec/gdbstub.h
index 1a01c35f8ec84b922c73a87420c7f9962abca055..a43aa34dadc349ad2d8a2577fc0a72a45f1ea623 100644 (file)
--- a/include/exec/gdbstub.h
+++ b/include/exec/gdbstub.h
@@ -13,6 +13,7 @@
 typedef struct GDBFeature {
     const char *xmlname;
     const char *xml;
+    int num_regs;
 } GDBFeature;
 
 

diff --git a/scripts/feature_to_c.py b/scripts/feature_to_c.py
index bcbcb83beb1f65d0e703b12b99696dec0a400d23..e04d6b2df7f7489117c1379c341008616aed9c84 100644 (file)
--- a/scripts/feature_to_c.py
+++ b/scripts/feature_to_c.py
@@ -1,7 +1,7 @@
 #!/usr/bin/env python3
 # SPDX-License-Identifier: GPL-2.0-or-later
 
-import os, sys
+import os, sys, xml.etree.ElementTree
 
 def writeliteral(indent, bytes):
     sys.stdout.write(' ' * indent)
@@ -39,10 +39,52 @@ for input in sys.argv[1:]:
     with open(input, 'rb') as file:
         read = file.read()
 
+    parser = xml.etree.ElementTree.XMLPullParser(['start', 'end'])
+    parser.feed(read)
+    events = parser.read_events()
+    event, element = next(events)
+    if event != 'start':
+        sys.stderr.write(f'unexpected event: {event}\n')
+        exit(1)
+    if element.tag != 'feature':
+        sys.stderr.write(f'unexpected start tag: {element.tag}\n')
+        exit(1)
+
+    regnum = 0
+    regnums = []
+    tags = ['feature']
+    for event, element in events:
+        if event == 'end':
+            if element.tag != tags[len(tags) - 1]:
+                sys.stderr.write(f'unexpected end tag: {element.tag}\n')
+                exit(1)
+
+            tags.pop()
+            if element.tag == 'feature':
+                break
+        elif event == 'start':
+            if len(tags) < 2 and element.tag == 'reg':
+                if 'regnum' in element.attrib:
+                    regnum = int(element.attrib['regnum'])
+
+                regnums.append(regnum)
+                regnum += 1
+
+            tags.append(element.tag)
+        else:
+            raise Exception(f'unexpected event: {event}\n')
+
+    if len(tags):
+        sys.stderr.write('unterminated feature tag\n')
+        exit(1)
+
+    base_reg = min(regnums)
+    num_regs = max(regnums) - base_reg + 1 if len(regnums) else 0
+
     sys.stdout.write('    {\n')
     writeliteral(8, bytes(os.path.basename(input), 'utf-8'))
     sys.stdout.write(',\n')
     writeliteral(8, read)
-    sys.stdout.write('\n    },\n')
+    sys.stdout.write(f',\n        {num_regs},\n    }},\n')
 
 sys.stdout.write('    { NULL }\n};\n')