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charset="us-ascii" Content-ID: Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: Dell.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: DS7PR19MB4501.namprd19.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: bb256ef1-f2e0-494a-aef6-08daae0ab22b X-MS-Exchange-CrossTenant-originalarrivaltime: 14 Oct 2022 17:36:58.8146 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 945c199a-83a2-4e80-9f8c-5a91be5752dd X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: zD7GvkaP2U2mz0BNa3lejxFPYO5225q4o/83/6cCJ1j6QdVBSsSkUuaTTvr7lpCyflOLwsYe16+Pnh148DupJw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH8PR19MB6569 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.895,Hydra:6.0.545,FMLib:17.11.122.1 definitions=2022-10-14_09,2022-10-14_01,2022-06-22_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxlogscore=944 impostorscore=0 phishscore=0 spamscore=0 priorityscore=1501 mlxscore=0 adultscore=0 clxscore=1015 lowpriorityscore=0 bulkscore=0 malwarescore=0 suspectscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2209130000 definitions=main-2210140097 X-Proofpoint-ORIG-GUID: myCHuzXo9Ejeb-CmayIY-C-OqQP69WKr X-Proofpoint-GUID: myCHuzXo9Ejeb-CmayIY-C-OqQP69WKr X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 malwarescore=0 mlxscore=0 phishscore=0 adultscore=0 suspectscore=0 spamscore=0 mlxlogscore=999 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2209130000 definitions=main-2210140097 X-Spam-Status: No, score=-2.5 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_MSPIKE_H2,SPF_HELO_NONE,SPF_NONE,TXREP autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: > On Oct 14, 2022, at 1:10 PM, Jeff Law wrote: >=20 > On 10/14/22 10:37, Koning, Paul wrote: >>=20 >>> ... >>> But that approach falls down with reload/lra doing substitutions withou= t validating the result. I guess it might be possible to cobble together s= omething with secondary reloads, but it's way way way down on my todo list. >> Aren't the constraints enforced? My experience is that I was getting th= ese bad addressing modes in some test programs, and that the constraints I = created to make the requirement explicit cured that. Maybe I'm expecting t= oo much from constraints, but my (admittedly inexperienced) understanding o= f them is that they inform reload what sort of things it can construct, and= what it cannot. >=20 > It's not really a constraint issue -- the pattern's condition would cause= this not to recognize, but LRA doesn't re-recognize the insn. We might be= able to hack something in the constraints to force a reload of the source = operand in this case. Ugly, but a possibility. I find it hard to cope with constraints that don't constrain. Minimally it= should be clearly documented exactly what cases fail to obey the constrain= ts and what a target writer can do to deal with those failures. As it stands, I find myself working hard to write MD code that accurately d= escribes the rules of the machine, and for the core machinery to disregard = those instructions is painful. Is there a compelling argument for every case where LRA fails to obey the c= onstraints? If not, can they just be called bugs and added to the to-be-fi= xed queue? paul