Truffle:  NPE guard in InstrumentationNode
Truffle:  additional methods on ExecutionContext
Merge with 5c73b162eec248fc2d06f59d8f25860871a21be5
Remove isCompressible flags from memory access nodes.

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extra : rebase_source : 0b8465175cdd3f78e50d19efffb75ef8c577881c
extra : __touch-noise__ : 3418061426
Remove unused oop compression code from backends.

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extra : rebase_source : 44bd7faaefb594f5992807d4fa07d4a18412db60
extra : __touch-noise__ : 2331392401
Ensure values stay finite in block probability computation.

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extra : rebase_source : aa83fbac352832133765415f9635cb8579e9c4df
extra : __touch-noise__ : 1932050515
Fix insertion of profile data in unit tests.

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extra : rebase_source : 3b9346299e3cdff2fe60b5378f32b929df24df9b
extra : __touch-noise__ : 2909714356
Interface to do graph verification after High/Mid/LowTier in unittests.

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extra : rebase_source : 1cc6c2ee081d9772b5b3028b9ad067362c583a08
extra : __touch-noise__ : 4045882585
do not count the memory allocated by ThreadMXBean.getThreadAllocatedBytes()
made more services implement com.oracle.graal.api.runtime.Service for faster loading
generate more efficient code for GraalRuntime::get_service_impls
grow NodeMaps exponentially
ignore transient fields in NodeClass
cache last receiver stamp in MethodCallTargetNode
long values and scale on DebugHistogram
NodeBitMap refactoring
NodeWorkList refactoring
more improvements to runtime initialization:
- replaced HotSpotSymbol with native method for reading a symbol
- moved more ForeignCallDescriptors to HotSpotBackend to reduce class initialization
less canonicalization during InliningPhase
IfNode refactorings