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X-OriginatorOrg: arm.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 12 Dec 2022 14:35:05.5744 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: d6701829-5c76-4b01-28ba-08dadc4e0fc8 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: VI1EUR03FT017.eop-EUR03.prod.protection.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: AS8PR08MB8249 X-Spam-Status: No, score=-5.1 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,=0A= =0A= I don't believe there is a missing optimization here: compilers expand memp= cpy=0A= by default into memcpy since that is the standard library call. That means = even=0A= if your source code contains mempcpy, there will never be any calls to memp= cpy.=0A= =0A= The reason is obvious: most targets support optimized memcpy in the C libra= ry=0A= while very few optimize mempcpy. The same is true for bzero, bcmp and bcopy= .=0A= =0A= Targets can do it differently, IIRC x86 is the only target that emits calls= both to=0A= memcpy and mempcpy.=0A= =0A= Cheers,=0A= Wilco=