compiler/iface/BinIface.hs¶
Note [Symbol table representation of names]¶
An occurrence of a name in an interface file is serialized as a single 32-bit word. The format of this word is:
- 00xxxxxx xxxxxxxx xxxxxxxx xxxxxxxx
- A normal name. x is an index into the symbol table
- 10xxxxxx xxyyyyyy yyyyyyyy yyyyyyyy
- A known-key name. x is the Unique’s Char, y is the int part. We assume that all known-key uniques fit in this space. This is asserted by PrelInfo.knownKeyNamesOkay.
During serialization we check for known-key things using isKnownKeyName. During deserialization we use lookupKnownKeyName to get from the unique back to its corresponding Name.
See Note [Symbol table representation of names]
