On Fri, 4 Mar 2022 18:33:53 +0000, Schmitt, Michael <[email protected]> wrote:
>Am I correct in assuming that branch relative (HLASM "jump") instructions are >more efficient than branches using register+displacement? Yes. It´s easier for the Branch Prediction Unit to find the target address using relative offset. > >C. Kevin Shum's IBM Z System Processor Optimization Primer says: > >Use relative branches instead of non-relative (indirect branches) when possible > >but "indirect" is what throws me. The only indirect branch I'm aware of is >Branch Indirect on Condition (BIC). "Indirect" because non-relative branch instructions depend on base register content at the time of execution. Regards, Philippe Leite LAB Services - IBM
