cfacd015b9
Before:
```
Tuple counts for Essa::ScopeEntryDefinition#class#24e22a14#f/1@45e0d8dh after 10.5s:
2133368 ~1% {2} r1 = Essa::TEssaNodeDefinition#24e22a14#ffff_03#join_rhs AND NOT Essa::ImplicitSubModuleDefinition#class#24e22a14#f(Lhs.1 'this')
534478950 ~0% {2} r2 = JOIN r1 WITH Definitions::SsaSourceVariable::getScopeEntryDefinition#dispred#f0820431#ff ON FIRST 1 OUTPUT Lhs.1 'this', Rhs.1
581249 ~4% {1} r3 = JOIN r2 WITH Essa::EssaNodeDefinition::getDefiningNode#dispred#f0820431#ff ON FIRST 2 OUTPUT Lhs.0 'this'
return r3
```
Let's see if pushing the `getDefiningNode` join further up improves the
number of intermediary tuples. (Intuitively it should, since there
should only be one defining node for any given `EssaNodeDefinition`.)
To do this, we unbind the `this.getSourceVariable()` part, which
encourages the compiler to put this join later.
After:
```
Tuple counts for Essa::ScopeEntryDefinition#class#24e22a14#f/1@30758cv4 after 300ms:
2133569 ~1% {2} r1 = SCAN Essa::TEssaNodeDefinition#24e22a14#ffff OUTPUT In.0, In.3 'this'
2133368 ~1% {2} r2 = r1 AND NOT Essa::ImplicitSubModuleDefinition#class#24e22a14#f(Lhs.1 'this')
2133368 ~0% {2} r3 = JOIN r2 WITH Definitions::SsaSourceVariable#class#486534ab#f ON FIRST 1 OUTPUT Lhs.1 'this', Lhs.0
2133368 ~0% {3} r4 = JOIN r3 WITH Essa::EssaNodeDefinition::getDefiningNode#dispred#f0820431#ff ON FIRST 1 OUTPUT Lhs.1, Rhs.1, Lhs.0 'this'
581249 ~4% {1} r5 = JOIN r4 WITH Definitions::SsaSourceVariable::getScopeEntryDefinition#dispred#f0820431#ff ON FIRST 2 OUTPUT Lhs.2 'this'
return r5
```
Much better (and our intuition is confirmed -- joining with
`getDefiningNode` did not increase the number of tuples).
CodeQL
This open source repository contains the standard CodeQL libraries and queries that power GitHub Advanced Security and the other application security products that GitHub makes available to its customers worldwide.
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