Use fast varint read path in LongInputStreamV1

[oerling]

Do not decode varints that are skipped over and do not maintain a
buffer of possibly unused values. Use the OrcInputStream varint
methods to read or skip only what is needed.

[highker]

minor comment only; otherwise LGTM

[highker]

lastReadInputCheckpoint is never used anymore. Could you remove?

[highker]

remove (): used * delta

[highker]

Could you give a more meaningful name for this?

[oerling]

I addressed the comments. I numInRun -> numValuesInRun. This was in Bhavani’s last verifier run and did not make new bugs. From: James Sun <notifications@github.com> Sent: Saturday, October 26, 2019 12:55 AM To: prestodb/presto <presto@noreply.github.com> Cc: oerling <erling@xs4all.nl>; Author <author@noreply.github.com> Subject: Re: [prestodb/presto] Use fast varint read path in LongInputStreamV1 (#13607) @highker commented on this pull request. minor comment only; otherwise LGTM

_____ In presto-orc/src/main/java/com/facebook/presto/orc/stream/LongInputStreamV1.java <#13607 (comment)> :

@@ -41,8 +40,7 @@ public LongInputStreamV1(OrcInputStream input, boolean signed)

lastReadInputCheckpoint = input.getCheckpoint(); lastReadInputCheckpoint is never used anymore. Could you remove?

_____ In presto-orc/src/main/java/com/facebook/presto/orc/stream/LongInputStreamV1.java <#13607 (comment)> :

}

if (repeat) { - result = literals[0] + (used++) * delta; + result = repeatBase + (used) * delta; remove (): used * delta

_____ In presto-orc/src/main/java/com/facebook/presto/orc/stream/LongInputStreamV1.java <#13607 (comment)> :

private final OrcInputStream input; private final boolean signed; - private final long[] literals = new long[MAX_LITERAL_SIZE]; - private int numLiterals; + private long repeatBase; + private int numInRun; Could you give a more meaningful name for this? — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#13607?email_source=notifications&email_token=AKPPPT6XZTICVF56GCIHZ7TQQPZUBA5CNFSM4JFFZFZKYY3PNVWWK3TUL52HS4DFWFIHK3DMKJSXC5LFON2FEZLWNFSXPKTDN5WW2ZLOORPWSZGOCJKFEWY#pullrequestreview-307515995> , or unsubscribe <https://github.com/notifications/unsubscribe-auth/AKPPPT4KXYGXNUXFHKUMC3TQQPZUBANCNFSM4JFFZFZA> .

[highker]

LGTM