FEAT_MTE and FEAT_TBI allow applications to insert tags into the high bits of addresses which will be ignored (TBI) or verified (MTE) by hardware. We need to make sure DynamoRIO can handle apps which use these features.

Some areas that have already been identified that need special handling:

• code cache tags

• mmap/mprotect/etc syscall handling when called with a tagged address

• drmemtrace offline trace format assumes address bits 48..63 are always identical (see trace_entry.h:913)

Android 11+ uses a tagging heap allocator by default: https://source.android.com/docs/security/test/scudo