From 308b4b60809fbc2e47c2ad308ac81776a764b946 Mon Sep 17 00:00:00 2001
From: Christopher Haster <geky@geky.net>
Date: Wed, 4 Dec 2024 10:48:34 -0600
Subject: [PATCH] scripts: Made dwarf tags explicit in ctx.py/structs.py

This will make ctx.py/structs.py more likely to error on unknown tags,
which is preferable to silently reporting incorrect numbers.
---
 scripts/ctx.py     | 32 ++++++++++++++++++++++++++------
 scripts/structs.py | 26 +++++++++++++++++++++++---
 2 files changed, 49 insertions(+), 9 deletions(-)

diff --git a/scripts/ctx.py b/scripts/ctx.py
index 8a644b3d..317ca3b2 100755
--- a/scripts/ctx.py
+++ b/scripts/ctx.py
@@ -552,12 +552,22 @@ def collect(obj_paths, *,
             # function pointer?
             elif entry.tag == 'DW_TAG_subroutine_type':
                 size = 0
-            # probably a modifier
-            elif 'DW_AT_type' in entry:
+            # a modifier?
+            elif (entry.tag in {
+                        'DW_TAG_typedef',
+                        'DW_TAG_array_type',
+                        'DW_TAG_enumeration_type',
+                        'DW_TAG_formal_parameter',
+                        'DW_TAG_member',
+                        'DW_TAG_const_type',
+                        'DW_TAG_volatile_type',
+                        'DW_TAG_restrict_type'}
+                    and 'DW_AT_type' in entry):
                 type = info[int(entry['DW_AT_type'].strip('<>'), 0)]
                 size = sizeof(type, seen | {entry.off})
             # void?
-            elif 'DW_AT_byte_size' not in entry:
+            elif ('DW_AT_type' not in entry
+                    and 'DW_AT_byte_size' not in entry):
                 size = 0
             else:
                 assert False, "Unknown dwarf entry? %r" % entry.tag
@@ -616,13 +626,23 @@ def collect(obj_paths, *,
                     'DW_TAG_base_type',
                     'DW_TAG_subroutine_type'}:
                 children, notes = [], []
-            # probably a modifier
-            elif 'DW_AT_type' in entry:
+            # a modifier?
+            elif (entry.tag in {
+                        'DW_TAG_typedef',
+                        'DW_TAG_array_type',
+                        'DW_TAG_enumeration_type',
+                        'DW_TAG_formal_parameter',
+                        'DW_TAG_member',
+                        'DW_TAG_const_type',
+                        'DW_TAG_volatile_type',
+                        'DW_TAG_restrict_type'}
+                    and 'DW_AT_type' in entry):
                 type = int(entry['DW_AT_type'].strip('<>'), 0)
                 children, notes = childrenof(
                         info[type], seen | {entry.off})
             # void?
-            elif 'DW_AT_byte_size' not in entry:
+            elif ('DW_AT_type' not in entry
+                    and 'DW_AT_byte_size' not in entry):
                 children, notes = [], []
             else:
                 assert False, "Unknown dwarf entry? %r" % entry.tag
diff --git a/scripts/structs.py b/scripts/structs.py
index 3f9ddba4..d03299f0 100755
--- a/scripts/structs.py
+++ b/scripts/structs.py
@@ -397,7 +397,13 @@ def collect(obj_paths, *,
                     if child.tag == 'DW_TAG_subrange_type':
                         size *= int(child['DW_AT_upper_bound']) + 1
             # indirect type?
-            elif 'DW_AT_type' in entry:
+            elif entry.tag in {
+                    'DW_TAG_typedef',
+                    'DW_TAG_enumeration_type',
+                    'DW_TAG_member',
+                    'DW_TAG_const_type',
+                    'DW_TAG_volatile_type',
+                    'DW_TAG_restrict_type'}:
                 type = info[int(entry['DW_AT_type'].strip('<>'), 0)]
                 size = sizeof(type)
             else:
@@ -429,7 +435,14 @@ def collect(obj_paths, *,
                     'DW_TAG_union_type'}:
                 align = max(alignof(child) for child in entry.children)
             # indirect type?
-            elif 'DW_AT_type' in entry:
+            elif entry.tag in {
+                    'DW_TAG_typedef',
+                    'DW_TAG_array_type',
+                    'DW_TAG_enumeration_type',
+                    'DW_TAG_member',
+                    'DW_TAG_const_type',
+                    'DW_TAG_volatile_type',
+                    'DW_TAG_restrict_type'}:
                 type = int(entry['DW_AT_type'].strip('<>'), 0)
                 align = alignof(info[type])
             else:
@@ -466,7 +479,14 @@ def collect(obj_paths, *,
                             i=child.off,
                             children=children_))
             # indirect type?
-            elif 'DW_AT_type' in entry:
+            elif entry.tag in {
+                    'DW_TAG_typedef',
+                    'DW_TAG_array_type',
+                    'DW_TAG_enumeration_type',
+                    'DW_TAG_member',
+                    'DW_TAG_const_type',
+                    'DW_TAG_volatile_type',
+                    'DW_TAG_restrict_type'}:
                 type = int(entry['DW_AT_type'].strip('<>'), 0)
                 children = childrenof(info[type])
             else: