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e523f93d91
This query seems to have been de-optimized by recent optimizer or stats
changes. On libretro/libretro-uae, the query took 1 second on a warm
cache with dist 89ad5f1 but took 9979 seconds with dist a3b9b6eb9.
The slowness was due to a Cartesian product in
`illDefined{Decr,Incr}ForStmt` between all the definitions and all the
uses of `Variable v`. This would be no problem with the right join
order, but that has apparently been lost. This commit factors out a pair
of `pragma[noinline]` helper predicates to make sure the definitions
(`v.getAnAssignedValue()`) and the uses (`v.getAnAccess()`) are queried
and filtered in separate predicates.
The performance problem can be seen in the tuple counts of this pipeline
I interrupted during evaluation of
`inconsistentLoopDirection::illDefinedDecrForStmt#ffff#shared`:
89716 ~3% {2} r1 = SCAN Variable::Variable::getAnAssignedValue_dispred#ff OUTPUT FIELDS {Variable::Variable::getAnAssignedValue_dispred#ff.<1>,Variable::Variable::getAnAssignedValue_dispred#ff.<0>}
89716 ~0% {3} r2 = JOIN r1 WITH DataFlowUtil::TExprNode#ff@staged_ext ON r1.<0>=DataFlowUtil::TExprNode#ff@staged_ext.<0> OUTPUT FIELDS {r1.<1>,DataFlowUtil::TExprNode#ff@staged_ext.<0>,DataFlowUtil::TExprNode#ff@staged_ext.<1>}
502539405 ~0% {4} r3 = JOIN r2 WITH Variable::Variable::getAnAccess_dispred#fb ON r2.<0>=Variable::Variable::getAnAccess_dispred#fb.<0> OUTPUT FIELDS {Variable::Variable::getAnAccess_dispred#fb.<1>,r2.<1>,r2.<2>,r2.<0>}
return r3