tree 416f0b3c24f62057eea5af405304bfc91fd4020c
parent e60f103d2d3541e57a6ca8d788e959e03b615e5f
author Jakob Stoklund Olesen <stoklund@2pi.dk> 1311391353 +0000
committer Jakob Stoklund Olesen <stoklund@2pi.dk> 1311391353 +0000

Prepare RAGreedy::growRegion for compact regions.

A split candidate can have a null PhysReg which means that it doesn't
map to a real interference pattern. Instead, pretend that all through
blocks have interference.

This makes it possible to generate compact regions where the live range
doesn't go through blocks that don't use it. The live range will still
be live between directly connected blocks with uses.

Splitting around a compact region tends to produce a live range with a
high spill weight, so it may evict a less dense live range.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135845 91177308-0d34-0410-b5e6-96231b3b80d8