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X-OriginatorOrg: arm.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 06 Feb 2023 16:53:50.8840 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: b3686766-df3d-4a2f-a904-08db0862b923 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: DBAEUR03FT056.eop-EUR03.prod.protection.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: PAVPR08MB9842 X-Spam-Status: No, score=-5.0 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,FORGED_SPF_HELO,KAM_DMARC_NONE,RCVD_IN_DNSWL_NONE,RCVD_IN_MSPIKE_H2,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 Jun,=0A= =0A= > Removing zero bits from multiply and making shifts afterwards can extend = the time before=0A= > overflow.=A0 Does it also reduce the resolution of the timer?=0A= =0A= It wouldn't if we shift out zero bits. For example 1000000 has 6 zero bits= =0A= at the bottom, so assuming every implementation uses a multiple of 1MHz=0A= then there is no loss of accuracy. And 6 extra bits would mean 1024 seconds= =0A= before overflow at 1GHz which seems long enough.=0A= =0A= Cheers,=0A= Wilco=