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X-OriginatorOrg: arm.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 07 Mar 2023 22:13:50.6686 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: b7b674f9-2100-4d35-ab9f-08db1f593b12 X-MS-Exchange-CrossTenant-Id: f34e5979-57d9-4aaa-ad4d-b122a662184d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=f34e5979-57d9-4aaa-ad4d-b122a662184d;Ip=[63.35.35.123];Helo=[64aa7808-outbound-1.mta.getcheckrecipient.com] X-MS-Exchange-CrossTenant-AuthSource: DBAEUR03FT011.eop-EUR03.prod.protection.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: GV1PR08MB8034 X-Spam-Status: No, score=-5.4 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,FORGED_SPF_HELO,KAM_DMARC_NONE,RCVD_IN_DNSWL_NONE,SPF_HELO_PASS,SPF_NONE,TXREP,UNPARSEABLE_RELAY autolearn=no autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: Hi,=0A= =0A= Note the same code seems to be posted several times on Stackoverflow, eg.= =0A= [1], [2] - are they all the same author?=0A= =0A= Also doing repeated division steps using CLZ is still essentially doing 1 b= it at=0A= a time. Previously we've had a patch doing 11+ bits per iteration using div= ision.=0A= In both cases you need hardware support or performance will be significantl= y=0A= worse. The fastest solution is using a single division followed by multiply= by=0A= inverse - LLVM seems to have adopted that.=0A= =0A= Cheers,=0A= Wilco=0A= =0A= [1] https://stackoverflow.com/questions/69222373/fastest-way-for-wrapping-a= -value-in-an-interval=0A= [2] https://stackoverflow.com/questions/41685039/is-fmod-faster-than-for-in= teger-modulus-calculation=