port: advance VC6 typeobject frontier and preserve regression coverage

2026-10-26 18:09:33 +00:00
parent 35caf1a558
commit 5ab291a68c
162 changed files with 15675 additions and 85 deletions
@@ -0,0 +1,60 @@
+#!/usr/bin/env python3
+"""Guard only arena_map_mark_used's entry locals and original operation order."""
+
+import re
+import sys
+from pathlib import Path
+
+source = Path(sys.argv[1]).read_text()
+match = re.search(
+    r"\narena_map_mark_used\(uintptr_t arena_base, int is_used\)\s*\{(.*?)\n\}",
+    source, re.S,
+)
+assert match, "arena_map_mark_used definition not found"
+body = re.sub(r"/\*.*?\*/", "", match.group(1), flags=re.S)
+declarations = """
+    arena_map_bot_t *n_hi;
+    int i3;
+    int32_t tail;
+    uintptr_t arena_base_next;
+    arena_map_bot_t *n_lo;
+    int i3_next;
+"""
+assert body.split()[:len(declarations.split())] == declarations.split(), (
+    "n_hi, i3, tail, arena_base_next, n_lo, i3_next must be declared without initializers at function entry"
+)
+
+# Keep evaluations at their original positions: the sanity assertion precedes
+# lookup; failed lookup returns before index/tail evaluation. Lock both branches,
+# including rollback and i3_next evaluation after the n_lo NULL return.
+expected = declarations + """
+    assert(HIGH_BITS(arena_base) == HIGH_BITS(&arena_map_root));
+    n_hi = arena_map_get((block *)arena_base, is_used);
+    if (n_hi == NULL) {
+        assert(is_used);
+        return 0;
+    }
+    i3 = MAP_BOT_INDEX((block *)arena_base);
+    tail = (int32_t)(arena_base & ARENA_SIZE_MASK);
+    if (tail == 0) {
+        n_hi->arenas[i3].tail_hi = is_used ? -1 : 0;
+    }
+    else {
+        n_hi->arenas[i3].tail_hi = is_used ? tail : 0;
+        arena_base_next = arena_base + ARENA_SIZE;
+        assert(arena_base < arena_base_next);
+        n_lo = arena_map_get((block *)arena_base_next, is_used);
+        if (n_lo == NULL) {
+            assert(is_used);
+            n_hi->arenas[i3].tail_hi = 0;
+            return 0;
+        }
+        i3_next = MAP_BOT_INDEX(arena_base_next);
+        n_lo->arenas[i3_next].tail_lo = is_used ? tail : 0;
+    }
+    return 1;
+"""
+assert body.split() == expected.split(), (
+    "preserve original initialization/evaluation/control-flow order"
+)
+print("obmalloc arena_map_mark_used entry declarations and original operation order: PASS")