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Static Chain Maintenance

• At the call (assume there are no parameters that are subprograms and no pass-by-name parameters):
  • The activation record instance must be built
  • The dynamic link is just the old frame pointer
  • The static link must point to the most recent ARI of the static parent (in most situations)

• Best method:
  • If A calls B, then B's static link should be set to the ARI that is (static_depth(A) – static_depth(B) + 1) links along the static chain starting at A
  • Amounts to treating subprogram calls and definitions like variable references and definitions, and then using the chain_offset
  • This info can be computed statically by the compiler