[Dlight] Fix general reduction rule to support non-last reduction axis #17754
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This PR fixes a bug in the general reduction dlight rule, which happens when there is a trailing spatial block, and for the previous reduction blocks, the reduction axes are not on the back. In the case above, the loop orders of the reduction blocks and the trailing spatial block are inconsistent, while the dlight rule before this fix always treat the loop orders as consistent. As a result, though the function after applying the rule is numerically correct, it may require much extra shared memory use (in proportion to the size of spatial loops). And when the spatial dimensions are large, the required share memory size may exceed the device limit. This PR fixes this bug and adds a unit test.
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apache#17754) This PR fixes a bug in the general reduction dlight rule, which happens when there is a trailing spatial block, and for the previous reduction blocks, the reduction axes are not on the back. In the case above, the loop orders of the reduction blocks and the trailing spatial block are inconsistent, while the dlight rule before this fix always treat the loop orders as consistent. As a result, though the function after applying the rule is numerically correct, it may require much extra shared memory use (in proportion to the size of spatial loops). And when the spatial dimensions are large, the required share memory size may exceed the device limit. This PR fixes this bug and adds a unit test.
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This PR fixes a bug in the general reduction dlight rule, which happens when there is a trailing spatial block, and for the previous reduction blocks, the reduction axes are not on the back.
In the case above, the loop orders of the reduction blocks and the trailing spatial block are inconsistent, while the dlight rule before this fix always treat the loop orders as consistent.
As a result, though the function after applying the rule is numerically correct, it may require much extra shared memory use (in proportion to the size of spatial loops). And when the spatial dimensions are large, the required share memory size may exceed the device limit.
This PR fixes this bug and adds a unit test.