[ORC-1122] Add buffer to decode the whole run in RleDecoderV2

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.8.0
• Fix Version/s: 1.8.0
• Component/s: C++
• Assignee: Quanlong Huang
• Reporter: Quanlong Huang
• Created: 04/Mar/22 12:09
• Updated: 03/Sep/22 22:43
• Resolved: 11/Mar/22 08:18

Description

This is a follow up task of ORC-1020 which didn't optimize the code path when the run has nulls. Adding a buffer to decode the whole run at once can leverage the improvement of ORC-1020. Not just for the DIRECT encoding, this also benifits other encodings like PATCHED_BASE and DELTA. It also helps to remove the state variables in RleDecoderV2 and improves the code redability.

Issue Links

• links to: GitHub Pull Request #1056