UnionDecl

Trailing:

0. tag_type: Ref, // if has_tag_type
1. captures_len: u32 // if has_captures_len
2. body_len: u32, // if has_body_len
3. fields_len: u32, // if has_fields_len
4. decls_len: u32, // if has_decls_len
5. capture: Capture // for every captures_len
6. capture_name: NullTerminatedString // for every captures_len
7. decl: Index, // for every decls_len; points to a declaration instruction
8. inst: Index // for every body_len
9. has_bits: u32 // for every 8 fields
   • sets of 4 bits: 0b000X: whether corresponding field has a type expression 0b00X0: whether corresponding field has a align expression 0b0X00: whether corresponding field has a tag value expression 0bX000: unused
10. fields: { // for every fields_len field_name: NullTerminatedString, // null terminated string index field_type: Ref, // if corresponding bit is set align: Ref, // if corresponding bit is set tag_value: Ref, // if corresponding bit is set }