C++: Fix join-order problem in getNextSwitchCase#21765
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jketema merged 4 commits intogithub:mainfrom Apr 28, 2026
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Before on `neovim`:
```
[2026-04-28 14:54:20] Evaluated non-recursive predicate Stmt::SwitchCase.getNextSwitchCase/0#dispred#2d3cb6d3@ac8178o2 in 68ms (size: 20848).
Evaluated relational algebra for predicate Stmt::SwitchCase.getNextSwitchCase/0#dispred#2d3cb6d3@ac8178o2 with tuple counts:
21888 ~0% {2} r1 = SCAN switch_case OUTPUT In.2, In.0
21888 ~0% {4} | JOIN WITH #switch_caseMerge_21#join_rhs ON FIRST 1 OUTPUT Lhs.1, Lhs.0, _, Rhs.1
21888 ~4% {3} | REWRITE WITH Tmp.2 := 1, Out.2 := (In.3 - Tmp.2) KEEPING 3
24091916 ~0% {3} | JOIN WITH switch_case ON FIRST 1 OUTPUT Lhs.2, Rhs.2, Lhs.1
20848 ~2% {2} | JOIN WITH #switch_caseMerge_12#join_rhs ON FIRST 2 OUTPUT Lhs.1, Lhs.2
return r1
```
After:
```
[2026-04-28 15:30:53] Evaluated non-recursive predicate Stmt::SwitchCase.getNextSwitchCase/0#dispred#2d3cb6d3@bf9801oj in 0ms (size: 20848).
Evaluated relational algebra for predicate Stmt::SwitchCase.getNextSwitchCase/0#dispred#2d3cb6d3@bf9801oj with tuple counts:
21888 ~0% {4} r1 = SCAN switch_case OUTPUT In.0, _, In.2, In.1
21888 ~1% {3} | REWRITE WITH Tmp.1 := 1, Out.1 := (In.3 + Tmp.1) KEEPING 3
20848 ~2% {2} | JOIN WITH switch_case ON FIRST 2 OUTPUT Lhs.2, Rhs.2
return r1
```
IdrissRio
requested changes
Apr 28, 2026
| * break; | ||
| * } | ||
| * ``` | ||
| * 0 yields `case 5:`, 1 yields `case 6:`, and 2 yields `default:`. |
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| * 0 yields `case 5:`, 1 yields `case 6:`, and 2 yields `default:`. | |
| * 0 yields `case 1:`, 1 yields `case 2:`, and 2 yields `default:`. |
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Fixed by updating the example instead.
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Author
|
DCA looks good. |
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