18b75d465b
## What changes were proposed in this pull request?
The current time complexity of ConstantPropagation is O(n^2), which can be slow when the query is complex.
Refactor the implementation with O( n ) time complexity, and some pruning to avoid traversing the whole `Condition`
## How was this patch tested?
Unit test.
Also simple benchmark test in ConstantPropagationSuite
```
val condition = (1 to 500).map{_ => Rand(0) === Rand(0)}.reduce(And)
val query = testRelation
.select(columnA)
.where(condition)
val start = System.currentTimeMillis()
(1 to 40).foreach { _ =>
Optimize.execute(query.analyze)
}
val end = System.currentTimeMillis()
println(end - start)
```
Run time before changes: 18989ms (474ms per loop)
Run time after changes: 1275 ms (32ms per loop)
Author: Wang Gengliang <ltnwgl@gmail.com>
Closes #19912 from gengliangwang/ConstantPropagation.
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