commit 58f9abc0975fb07dd98064b8f21c387bbc04bddc
author Jiyong Park <jiyong@google.com> Thu Aug 12 16:48:54 2021 +0900
committer Jiyong Park <jiyong@google.com> Fri Aug 13 13:07:18 2021 +0900
tree e10b4ff14615828bc2f0d9fcf13dbb0e9ebdb4d8
parent 45fc24917753f6765a0ba0ae67a6bf4b86e8fd25

idsig: less copies when creating the merkle tree

This change improves the merkle tree generation routine so that we don't
do unnecessary data copies. Previously, hashes for level N is written
to a temporary store and then copied into the tree. Even worse, the
hashes written to the tree is copied into another buffer when they are
used as the inputs for the next level.

With this CL, the hashes are directly written to and read from the tree.
This is done by having two (non-overlapping) slices on the hash tree.

Bug: N/A
Test: cargo test
Change-Id: I34be81ece6941eba78980c8bc4697ed5d523ed53