tree ba71a0603c98f09d31fa9b63d91544b8d0927ccf
parent 9d7c524c9bd603b1df9e88132f7ea4d59dab44a3
author David Brazdil <dbrazdil@google.com> 1461158652 +0100
committer David Brazdil <dbrazdil@google.com> 1461226984 +0100

Reduce memory usage in GVN

Implement recycling of ValueSet data structures which the GVN
algorithm will not access any more.

Savings depend on the shape of the graph, but can be as high as 93%.
Peak memory usage for GSA drops from 32MB to 26MB, compile times seem
unaffected.

Bug: 28173563
Bug: 28287086

Change-Id: If227177449bc90ad24fa68c37b0c2615924af1ed