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4830e43b3e
The `overlappingVariableMemoryLocations` predicate was a helper
predicate introduced to fix a join-order issue in
`overlappingIRVariableMemoryLocations`. Unfortunately it caused a
performance issue of its own because it could grow too large. On the
small project (38MB zip) awslabs/s2n there were 181M rows in
`overlappingVariableMemoryLocations`, and it took 134s to evaluate.
The fix is to collapse the two predicates into one and fix join ordering
by including an extra column in the predicates being joined.
In addition, some parameters were reordered to avoid the overhead of
auto-generated `join_rhs` predicates.
Tuple counts of `overlappingVariableMemoryLocations` before:
623285 ~176% {2} r1 = JOIN AliasedSSA::isCoveredOffset#fff_120#join_rhs AS L WITH AliasedSSA::isCoveredOffset#fff_120#join_rhs AS R ON FIRST 2 OUTPUT L.<2>, R.<2>
119138 ~3% {2} r2 = SCAN AliasedSSA::VariableMemoryLocation::getVirtualVariable_dispred#ff AS I OUTPUT I.<1>, I.<0>
172192346 ~0% {2} r3 = JOIN r2 WITH AliasedSSA::hasUnknownOffset#ff_10#join_rhs AS R ON FIRST 1 OUTPUT R.<1>, r2.<1>
172815631 ~0% {2} r4 = r1 \/ r3
172192346 ~0% {2} r5 = JOIN r2 WITH AliasedSSA::hasUnknownOffset#ff_10#join_rhs AS R ON FIRST 1 OUTPUT r2.<1>, R.<1>
345007977 ~87% {2} r6 = r4 \/ r5
return r6
Tuple counts of `overlappingIRVariableMemoryLocations` after:
117021 ~134% {2} r1 = JOIN AliasedSSA::isCoveredOffset#ffff AS L WITH AliasedSSA::isCoveredOffset#ffff AS R ON FIRST 3 OUTPUT L.<3>, R.<3>
201486 ~1% {2} r2 = JOIN AliasedSSA::hasUnknownOffset#fff AS L WITH AliasedSSA::hasVariableAndVirtualVariable#fff AS R ON FIRST 2 OUTPUT L.<2>, R.<2>
318507 ~26% {2} r3 = r1 \/ r2
201486 ~3% {2} r4 = JOIN AliasedSSA::hasUnknownOffset#fff AS L WITH AliasedSSA::hasVariableAndVirtualVariable#fff AS R ON FIRST 2 OUTPUT R.<2>, L.<2>
519993 ~92% {2} r5 = r3 \/ r4
return r5