Merge pull request #3185 from mthom/install_verify_attr_opt

Optimize `verify_attr` by removing the need to scan instructions

diff --cc src/machine/attributed_variables.rs
Simple merge

diff --cc src/machine/dispatch.rs
Simple merge

diff --cc src/machine/machine_state.rs
Simple merge

diff --cc src/machine/machine_state_impl.rs
Simple merge

diff --cc src/machine/mod.rs
Simple merge

diff --cc src/machine/system_calls.rs
Simple merge

diff --cc src/macros.rs
Simple merge