Using Optimizer

Optimizer works on the compiler-produced source listing and object code of a program. It greatly enhances the source listing while reducing the execution-time. This is accomplished by optimizing the object code. Optimizer often eliminates 30% or more of the machine instructions. In addition, Optimizer optionally "instruments" the object code in a variety of ways. Thus, you are provided with, not only testing and quality assurance tools, but production time diagnostic facilities as well.

Optimizer does not change the processing performed by the program or alter user-defined data areas. An optimized program does the same job, but does it faster. However, an optimized program may require additional CA Optimizer/II modules at execution-time, depending upon the options selected at compile/optimize time. The following is a partial list of the object code optimization techniques:

• Optimizing
  • Register usage
  • Addressing for Data and Procedure Division references
  • Subscript and index calculations
• Eliminating
  • Redundant instructions
  • Repetitive calculations
• Consolidating
  • MOVEs whenever possible
  • Repeated logic with global analysis
• Removing unreferenced code
• Reducing PERFORM linkage to as little as one instruction
• Taking code out of loops
• Simplifying IF logic

The following is a partial list of the enhanced source listing report features:

• Full merged cross-reference (MXREF)
• Merged data map (MMAP)
• Merged condensed procedure listing (MOFFSET)
• Summary of unconditionally true or false code and nonexecutable code
• PERFORM Range Summary with identification of PERFORM ranges violating structured programming techniques
• Compiler error messages "folded" for viewing on an 80-character width screen
• Complete Memory Map display (TGT/PGT) with one line for each possible area (for example, BLFs), even if the area is of zero length in the program
• An optimization results report which includes object code optimization results