Understanding When and How to Optimize

To produce an executable, you may just select the VB File menu and choose Make. VB also gives you several choices when you are ready to produce an EXE file. These choices depend on whether you care to take advantage of the native code compiler.

In the following examples, you use one of the sample projects included with VB. The project file is Optimize.VBP. Assuming that you installed the sample files and that you used the default directory structure when you installed VB, you will find a separate directory containing the Optimize project under your VB Samples directory.

You can follow along with any project you like, of course, but this particular project also illustrates some of the optimization issues explored during the rest of this chapter. Therefore, it may be helpful to install it if you haven’t already done so.

1. Compiling to P-Code

2. Compiling to Native Code
   
   Basic Optimizations
   Optimizing for Fast Code
   Optimizing for Small Code, No Optimization
   Favoring Pentium Pro, Creating Symbolic Debug Info
   Results of Basic Optimization
   
   Advanced Optimizations
   Assuming No Aliasing
   Removing Array Bounds Checks
   Removing Integer Overflow Checks, Removing Floating-Point Error Checks
   Allowing Unrounded Floating-Point Operations, Removing Safe Pentium FDIV Checks

3. Using Compile On Demand