LIR ops cannot have null @Temp fields
Support null check directly on compressed oops.

--HG--
extra : rebase_source : 1808b1fe78290f880c9c4c36fcd84f2bc53d5b96
extra : amend_source : 0db91eca567ae9c93fe5e2344128ffe49f03ad6c
Move dominates() and isDominatedBy() from Block to AbstractBlock and make them static methods.

--HG--
extra : rebase_source : 2e76f62b3034788c6d0458f3a627889df4651229
do not start/stop Graal compilation queue if -XX:-UseGraalCompilationQueue
exclude CompilationTask from JaCoCo
made UseGraalCompilationQueue false by default to see if perf. issue(s) still exist
Backed out changeset: a1b9340534bf
fixed crash when -XX:-TieredCompilation -XX:-UseGraalCompilationQueue is specified
add support for new G1 marking behavior
Truffle/API:  new abstract TruffleScriptEngineFactory
Merge
pass make variables on the command line instead of in environment variables to simplify running the make on the command line without mx
fixed hang in non-COMPILERGRAAL builds when -Xcomp is specified
Merge.