diff mbox series

[RFC,03/24] gdbstub: Add num_regs member to GDBFeature

Message ID 20230731084354.115015-4-akihiko.odaki@daynix.com
State New
Headers show
Series plugins: Allow to read registers | expand

Commit Message

Akihiko Odaki July 31, 2023, 8:43 a.m. UTC 
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>
---
 include/exec/gdbstub.h  |  1 +
 scripts/feature_to_c.py | 46 +++++++++++++++++++++++++++++++++++++++--
 2 files changed, 45 insertions(+), 2 deletions(-)

Comments

Philippe Mathieu-Daudé July 31, 2023, 1:35 p.m. UTC | #1 
On 31/7/23 10:43, Akihiko Odaki wrote:
> 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.

Nice :)

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>

> Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
> ---
>   include/exec/gdbstub.h  |  1 +
>   scripts/feature_to_c.py | 46 +++++++++++++++++++++++++++++++++++++++--
>   2 files changed, 45 insertions(+), 2 deletions(-)
Alex Bennée Aug. 14, 2023, 11:44 a.m. UTC | #2 
Akihiko Odaki <akihiko.odaki@daynix.com> writes:

> 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: Alex Bennée <alex.bennee@linaro.org>
diff mbox series

Patch

diff --git a/include/exec/gdbstub.h b/include/exec/gdbstub.h
index bd5bc91dda..22e5add5b1 100644
--- 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 5a5b49367b..8eb8c81cf8 100755
--- a/scripts/feature_to_c.py
+++ b/scripts/feature_to_c.py
@@ -1,6 +1,6 @@ 
 #!/usr/bin/env python3
 
-import os, sys
+import os, sys, xml.etree.ElementTree
 
 def writeliteral(indent, bytes):
     sys.stdout.write(' ' * indent)
@@ -35,10 +35,52 @@  def writeliteral(indent, bytes):
     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')