Fix incorrect comment
authorJoseph Tremoulet <jotrem@microsoft.com>
Fri, 20 Jan 2017 21:42:28 +0000 (16:42 -0500)
committerJoseph Tremoulet <jotrem@microsoft.com>
Sat, 21 Jan 2017 01:30:35 +0000 (20:30 -0500)
commite37576d2823803f4424ad33c75ce6e132c5b7bfa
tree16edaafe8fbc8a5dd1f7a60505658e6d9ce4e99f
parentd80c8ec9d13953512a16369f5c56a24f3ee08855
Fix incorrect comment

Rewrite bogus reference to nonexistsent `m_HeapDef` to correctly refer to
`block->bbHeapDef`.  Also change "doesn't kill heap" to "doesn't kill heap
liveness" (since it still kills availability).

Also add clarifying comments where `bbHeapUse` and `bbHeapDef` are
declared.

Commit migrated from https://github.com/dotnet/coreclr/commit/1082757a43da09c22018a5457649b121b64a2d64
src/coreclr/src/jit/block.h
src/coreclr/src/jit/liveness.cpp