From 0a66bfe90ae3812b617ed22c1a951a90db3d0c2a Mon Sep 17 00:00:00 2001
From: Dan King <dking@broadinstitute.org>
Date: Wed, 11 Oct 2023 16:11:26 -0400
Subject: [PATCH 1/2] [query] no unnecessary object allocations in
 RegionMemory.allocate

Consider this:

```scala
class Foo {
   def bar(): (Long, Long) = (3, 4)

   def destructure(): Unit = {
     val (x, y) = bar()
   }

   def accessors(): Unit = {
     val zz = bar()
     val x = zz._1
     val y = zz._2
   }
}
```

These should be exactly equivalent, right? There's no way Scala would compile the match into
something horrible. Right? Right?

```
public void destructure();
  Code:
     0: aload_0
     1: invokevirtual #27                 // Method bar:()Lscala/Tuple2;
     4: astore_3
     5: aload_3
     6: ifnull        35
     9: aload_3
    10: invokevirtual #33                 // Method scala/Tuple2._1$mcJ$sp:()J
    13: lstore        4
    15: aload_3
    16: invokevirtual #36                 // Method scala/Tuple2._2$mcJ$sp:()J
    19: lstore        6
    21: new           #13                 // class scala/Tuple2$mcJJ$sp
    24: dup
    25: lload         4
    27: lload         6
    29: invokespecial #21                 // Method scala/Tuple2$mcJJ$sp."<init>":(JJ)V
    32: goto          47
    35: goto          38
    38: new           #38                 // class scala/MatchError
    41: dup
    42: aload_3
    43: invokespecial #41                 // Method scala/MatchError."<init>":(Ljava/lang/Object;)V
    46: athrow
    47: astore_2
    48: aload_2
    49: invokevirtual #33                 // Method scala/Tuple2._1$mcJ$sp:()J
    52: lstore        8
    54: aload_2
    55: invokevirtual #36                 // Method scala/Tuple2._2$mcJ$sp:()J
    58: lstore        10
    60: return

public void accessors();
  Code:
     0: aload_0
     1: invokevirtual #27                 // Method bar:()Lscala/Tuple2;
     4: astore_1
     5: aload_1
     6: invokevirtual #33                 // Method scala/Tuple2._1$mcJ$sp:()J
     9: lstore_2
    10: aload_1
    11: invokevirtual #36                 // Method scala/Tuple2._2$mcJ$sp:()J
    14: lstore        4
    16: return
```

Yeah, so, it extracts the first and second elements of the primitive-specialized tuple, constructs
a `(java.lang.Long, java.lang.Long)` Tuple, then does the match on that.

sigh.
---
 hail/src/main/scala/is/hail/annotations/RegionMemory.scala | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/hail/src/main/scala/is/hail/annotations/RegionMemory.scala b/hail/src/main/scala/is/hail/annotations/RegionMemory.scala
index 3261e4b70f7..c5e534f69a5 100644
--- a/hail/src/main/scala/is/hail/annotations/RegionMemory.scala
+++ b/hail/src/main/scala/is/hail/annotations/RegionMemory.scala
@@ -59,7 +59,9 @@ final class RegionMemory(pool: RegionPool) extends AutoCloseable {
   def getCurrentBlock(): Long = currentBlock
 
   private def allocateBigChunk(size: Long): Long = {
-    val (chunkPointer, chunkSize) = pool.getChunk(size)
+    val ret = pool.getChunk(size)
+    val chunkPointer = ret._1
+    val chunkSize = ret._2
     bigChunks.add(chunkPointer)
     totalChunkMemory += chunkSize
     chunkPointer

From d4829aa3c4fd5130b36bda15874828a8e0dc08bd Mon Sep 17 00:00:00 2001
From: Dan King <daniel.zidan.king@gmail.com>
Date: Mon, 16 Oct 2023 11:44:58 -0400
Subject: [PATCH 2/2] admonition

---
 hail/src/main/scala/is/hail/annotations/RegionMemory.scala | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hail/src/main/scala/is/hail/annotations/RegionMemory.scala b/hail/src/main/scala/is/hail/annotations/RegionMemory.scala
index c5e534f69a5..9eb44c69a33 100644
--- a/hail/src/main/scala/is/hail/annotations/RegionMemory.scala
+++ b/hail/src/main/scala/is/hail/annotations/RegionMemory.scala
@@ -60,7 +60,7 @@ final class RegionMemory(pool: RegionPool) extends AutoCloseable {
 
   private def allocateBigChunk(size: Long): Long = {
     val ret = pool.getChunk(size)
-    val chunkPointer = ret._1
+    val chunkPointer = ret._1  // Match expressions allocate https://github.com/hail-is/hail/pull/13794
     val chunkSize = ret._2
     bigChunks.add(chunkPointer)
     totalChunkMemory += chunkSize