ZIV and SIV loop dependence analysis.

Provides functionality to perform ZIV and SIV dependency analysis tests
between a load and store within the same loop.

Dependency tests rely on scalar analysis to prove and disprove dependencies
with regard to the loop being analysed.

Based on the 1990 paper Practical Dependence Testing by Goff, Kennedy, Tseng

Adds support for marking loops in the loop nest as IRRELEVANT.
Loops are marked IRRELEVANT if the analysed instructions contain
no induction variables for the loops, i.e. the loops induction
variable is not relevent to the dependence of the store and load.