Reduction series : [polly] Make reduction detection checks more robust - part 1 #75297
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Existing redection detection algorithm does two types of memory checks before marking a load store pair as reduction. First is to check if load and store are pointing to the same memory.This check right now detects the following case as reduction. sum[0] = sum[1] + A[i] This is because the check compares only base of the memory addresses involved and not their indices. This patch addresses this issue and introduces some debug prints. Added couple of test cases to verify the functionality of patch as well. Change-Id: Ibe523a7d5f1538162f802fb079f32b30ba32175f
efriedma-quic
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Feb 12, 2024
Existing reduction detection algorithm does two types of memory checks before marking a load store pair as reduction. Second check is to verify there is no other memory access in ScopStmt overlapping with the memory of load and store that forms the reduction. Existing check misses cases where there could be probable overlap such as A[V] += A[P]; In the above case there is chance of overlap between A[V] and A[P] which is missed. This commit addresses this by removing the parameter from space before checking for compatible space. Part 1 of this patch : [75297](#75297)
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Existing redection detection algorithm does two types of memory checks before marking a load store pair as reduction.
First is to check if load and store are pointing to the same memory.This check right now detects the following case as reduction. sum[0] = sum[1] + A[i]
This is because the check compares only base of the memory addresses involved and not their indices. This patch addresses this issue and introduces some debug prints. Added couple of test cases to verify the functionality of patch as well.