Values that are defined together are represented as a singly linked list. These
lists appear in:
- Instructions with multiple result values. The first result value is special, and the
following results form a linked list of Def extended_value table entries.
- EBB arguments are represented as a linked list of Argument extended_value
table entries. The EbbData struct has pointers to the first and last argument
to allow fast insertion at both ends.
Add a Values iterator type whicih can enumerate both kinds of value lists.
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