On 29/04/2016 9:35 PM, Windt, W.K.F. van der (Fred) wrote:
Here's the code.I wrote a simple program - it tight loops 1 billion times L R4,=A(1*1000*1000*1000) LTR R4,R4 J LOOP * LOOP DS 0D .LOOP START B NEXT NEXT JCT R4,LOOP The loop starts with a branch ... I tested it twice - when the CC is matched (branch happens) and when it is not matched (falls through) 1. When the CC is matched and branching happens, CPU TIME=2.94 seconds 2. When the CC is not matched the code falls through, CPU TIME=1.69 seconds - a reduction of 42%Uhm... I don't see any conditional branch at the start of the loop that branches or falls through?
Modify that snippet to BE NEXT and see what your results are.
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