[LV] Change opcode of FindLast/FindFirst recurrence to Instruction::Select #162252
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fhahn
approved these changes
Oct 7, 2025
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| // In-loop AnyOf and FindIV reductions are not yet supported. | ||
| RecurKind Kind = RdxDesc.getRecurrenceKind(); | ||
| if (RecurrenceDescriptor::isAnyOfRecurrenceKind(Kind) || |
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With this change, can we make Find* unreachable in getOpcode for now?
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Unlike AnyOf, FindLast/FindFirst are not related to an or operation. Therefore, it’s inappropriate to set the opcode of FindLast/FindFirst to Instruction::Or. Setting it to Instruction::Select is more appropriate.
This change also allows RecurrenceDescriptor::getReductionOpChain to find the recurrence chain for FindLast/FindFirst, which will help support in-loop FindLast/FindFirst reductions in the future.