Fix stop predicate #2537
Fix stop predicate #2537
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| // Second condition is simply to avoid predication on broadcasting axes as | ||
| // it's not required. | ||
| if (consumer_stop_indexing_it == consumer_stop_index_map.end() || | ||
| consumer_stop_indexing_it->second->isZeroInt()) { |
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Is it because the extent can be zero?
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Does this mean we end up seeing more predicates like 0 < T.size[0]?
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Just in case, can you leave a comment and mention we can't ignore the consumer stop index even if it's zero as the extent can be zero?
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I think other than loop rotation, it will be mostly 0 < 1? I can not think of a case where stop index is 0.
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I wonder if we would want to specialize a fusion for the case where there's no zero-dim tensor. Assuming that's the common case, having a compilation option flag to guarantee there's no zero-dim tensor seems reasonable. It's not clear to me how much perf overhead we would have due to the conservative assumption that there can be zero-dim tensors, but if that's something we want to optimize, it seems to make sense to have two compiled kernels, one for the common case and another as backup.
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Yeah, I agree. Don't know how much effort would be to add that option. I would wait until some user request us to improve empty tensor support. :)
Looks like there is another bug in stop predicate