Begin the loop identification process with the data structures and fundamental methods of back edge discovery.

Do not allow DEF signedness to become mixed due to propagation of USE operand signedness within an RTL.

Expand local variable tables to include incoming argument, callee-saved reg, and return address locations.

detection that emits TRUNCATION annotations.

Fix incomplete assignment operators used in copy constructors; fix algorithm for detecting aliased mem writes in global DU chains.