Learn one new instruction today – Compare and Branch – CRB. You can tighten your code just a bit with CRB, an instruction that combines a comparison operation on two registers with a branch operation – all in one line. It comes with some extended mnemonics that make it easy to use. Learn all about it here in the time it takes to finish a cup of coffee.
Instruction of the Day: CRB
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I *love* these new (since z10/2008) “Compare […] and Branch” instructions.
I also love how you explain the extended mnemonics. Even though they’re found in both the Principles of Operations and the Reference Summary, I always end up going to Tachyon when I need one:
http://www.tachyonsoft.com/inst390m.htm
… your explanation makes it easy to remember.
“Compare […] and Branch” in Principles of Operations:
http://publibz.boulder.ibm.com/epubs/pdf/dz9zr006.pdf – page 7-57
Extended-Mnemonic Suffixes for Compare-and-Branch:
http://publibz.boulder.ibm.com/epubs/pdf/dz9zs005.pdf – page 39
Many thanks 🙂