> 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? Fred! ------------------------------------------------------------------------------------------------------ ATTENTION: The information in this e-mail is confidential and only meant for the intended recipient. If you are not the intended recipient , don't use or disclose it in anyway. Please let the sender know and delete the message immediately. ------------------------------------------------------------------------------------------------------ ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
