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[mono] Avoid an assert if the class name table is too large. #85952

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Merged
merged 1 commit into from
May 10, 2023
Merged

[mono] Avoid an assert if the class name table is too large. #85952

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10 changes: 7 additions & 3 deletions src/mono/mono/mini/aot-compiler.c
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Original file line number Diff line number Diff line change
Expand Up @@ -11646,11 +11646,15 @@ emit_class_name_table (MonoAotCompile *acfg)
name_p = name_buf = (guint8 *)g_malloc0 (name_buf_size);
#endif

guint table_len = table->len;
if (table_size > 65000 || table->len > 65000) {
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Why 65000? (As opposed to 65534 or something)

Do we know how much over the limit the microsoft graph API is? I guess metadata tokens are effectively 24 bits right? so there could be as many as 2^24-1 classes in that assembly?

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I mean it's kind of too bad that the largest assembly is the one that gets penalized by not having fast name lookup

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65000 is used to avoid having to think about off by one errors. The assembly has about 40k classes, maybe linking is turned off for it.

table_size = 0;
table_len = 0;
}

/* FIXME: Optimize memory usage */
g_assert (table_size < 65000);
encode_int16 (GINT_TO_UINT16 (table_size), p, &p);
g_assert (table->len < 65000);
for (guint i = 0; i < table->len; ++i) {
for (guint i = 0; i < table_len; ++i) {
entry = (ClassNameTableEntry *)g_ptr_array_index (table, i);
if (entry == NULL) {
encode_int16 (0, p, &p);
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3 changes: 3 additions & 0 deletions src/mono/mono/mini/aot-runtime.c
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Expand Up @@ -2639,6 +2639,9 @@ mono_aot_get_class_from_name (MonoImage *image, const char *name_space, const ch
table_size = amodule->class_name_table [0];
table = amodule->class_name_table + 1;

if (table_size == 0)
return FALSE;

if (name_space [0] == '\0')
full_name = g_strdup_printf ("%s", name);
else {
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