[PATCH] D34667: [Demangler] [DO NOT SUBMIT] Initial patch for Microsoft demangler.

[Zachary Turner via Phabricator via llvm-commits]

zturner added inline comments.


================
Comment at: llvm/lib/Demangle/MicrosoftDemangle.cpp:663-666
+  if (consume("P6A")) {
+    read_func_ptr(ty);
+    return;
+  }
----------------
Ok, I think I get it.  Here's some pointers to member functions:

Ok I think I get it.  Here's some pointers to member functions:

```
PtrMemberFunction@@3P8TheClass@@EAAXXZEQ1
PtrPtrMemberFunction@@3PEAP8TheClass@@EAAXXZEA
PtrPtrPtrMemberFunction@@3PEAPEAP8TheClass@@EAAXXZEA
```

The key observation here is that the `8` (`8` here means member function pointer, as opposed to `6` in the case you've handled) doesn't necessarily come after the `P`.  So this logic will not work here.  I think you need to sink this conditional into the `read_pointee` function below.  First you read the `P`, then you call `read_pointee`, which sees `E` (64-bit, and indicates that the storage class needs to be read), then storage class `A` (no storage class), then indirect recursion back into `read_var_type()`.  It sees `P` again (pointer), then calls `read_pointee` again, this time there is no `E` (64-bit) or `A` (32-bit), but instead there is the number `8` (member function).

The same would apply to non-member functions, and the algorithm handles constness, reference, etc as well.  So this should handle the general case.


https://reviews.llvm.org/D34667