From the Docs
1964 0.85
Turn this on to enable the analysis compiler pass.
This is an additional pass on the instructions of a block of game code.
By analyzing what's ahead, the 1964 compiler is able to do more optimizations.
1964 1.1
In 1964's compiler, there are some optimizations that can only be achieved by knowing what code is ahead in a block of code. The purpose of the first pass is to collect this information so that the second pass can write code for these optimizations. The default setting is Yes. If this setting is set to No, there will not be a pass to collect this information. This feature was called Advanced Analysis in 1964 0.8.5.