Unary Elementwise Operators #
Semantic-preservation lemmas for single-parent, same-shape elementwise operators in the IR-to-compiled-runtime bridge.
The proof pattern is deliberately explicit: we check the one-parent contract, recover the typed parent index, build the compiled forward closure, prove that IR evaluation produces the same value, and then hand the tail of the graph to the shared semantic-equivalence finishing lemma. Keeping these branches named avoids a single monolithic recursive proof and gives reviewers stable theorem names for each primitive operator.
Build note: the unary branches are proof-heavy for the same reason as activations: Lean checks the
runtime shape cast, parent lookup, Except failure branches, and final DVal equality all in one
goal. The common unary skeleton belongs in SemanticEquivalenceCommon, keeping
this file as a short list of operator instances.
Semantic-preservation lemma for .abs lowering.
Semantic-preservation lemma for .sqrt lowering.
Semantic-preservation lemma for .inv lowering.