mirror of
https://github.com/jlengrand/kotlin.git
synced 2026-05-08 15:53:19 +00:00
Previous version of the boxing/unboxing analysis treated merging boxed and non-boxed values as a hazard.
If such merged values are not used (e.g., early return + local variables reused in inlined calls),
corresponding boxing/unboxing operations still can be optimized out.
All information related to boxed value usage by instructions is moved to 'BoxedValueDescriptor'.
Introduce "tainted" (and "clean") boxed values, with the following rules:
merge(B, B) = B, if unboxed types are compatible,
T, otherwise
merge(B, X) = T
merge(T, X) = T
where
X is a non-boxed value,
B is a "clean" boxed value,
T is a "tainted" boxed value.
Postpone decision about value merge hazards until a "tainted" value is used.
59 lines
1.5 KiB
Kotlin
Vendored
59 lines
1.5 KiB
Kotlin
Vendored
// FILE: test.kt
|
|
|
|
// @TestKt.class:
|
|
// 0 valueOf
|
|
// 0 Value\s\(\)
|
|
|
|
val mask = 127
|
|
val entries = IntArray(128)
|
|
val flags = BooleanArray(128)
|
|
|
|
fun distance(index: Int, hash: Int): Int = (128 + index - (hash and mask)) and mask
|
|
|
|
fun insertSad(x: Int): Boolean {
|
|
return insertWithBoxing(
|
|
x,
|
|
hash = { it },
|
|
equals = { a, b -> a == b },
|
|
isEmpty = { !flags[it] },
|
|
fetch = { entries[it] },
|
|
store = { i, x -> entries[i] = x; flags[i] = true; }
|
|
)
|
|
}
|
|
|
|
// FILE: inline.kt
|
|
inline fun <T> insertWithBoxing(entry: T,
|
|
hash: (T) -> Int,
|
|
equals: (T, T) -> Boolean,
|
|
isEmpty: (Int) -> Boolean,
|
|
fetch: (Int) -> T,
|
|
store: (Int, T) -> Unit): Boolean {
|
|
var currentEntry = entry
|
|
var index = hash(entry) and mask
|
|
var dist = 0
|
|
do {
|
|
if (isEmpty(index)) {
|
|
store(index, currentEntry)
|
|
return true
|
|
}
|
|
|
|
val existingEntry = fetch(index)
|
|
if (equals(existingEntry, currentEntry)) {
|
|
return false
|
|
}
|
|
|
|
val existingHash = hash(existingEntry)
|
|
val existingDistance = distance(index, existingHash)
|
|
if (existingDistance < dist) {
|
|
store(index, currentEntry)
|
|
currentEntry = existingEntry
|
|
dist = existingDistance
|
|
}
|
|
|
|
dist += 1
|
|
index = (index + 1) and mask
|
|
}
|
|
while (true)
|
|
}
|
|
|