The first phase of any program analysis using this framework yields
a transfer function for each region in a problem-specific form.
For each analysis, a representation for transfer functions
with the following operations must be provided:
The first phase computes relative information that summarizes the behavior of each region. To compute absolute information, a second phase may optionally be performed. The second phase determines absolute information on entry to each procedure and region, using the transfer functions found in the first phase to propagate a problem-specific data-flow value. A representation for this value must be provided, along with the following operations: