made commoning of loading constants non-configurable (GRAAL-508)
removed support for external nodes (GRAAL-508)
New assumption utilities.
Add Debug.isDumpEnabledForMethod() and Debug.isLogEnabledForMethod() use it to diable graph compression and enable guard-id-as-debug-id

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extra : rebase_source : 1847210a904218b3a190a132c656b6b940987eb4
extra : histedit_source : f384558b890c6840ef7ed01c33a66203429d45df%2Cd21562b9b0c803d3fffa9e5a9067dfffe7e1143a
Make LoweringPhase more robust to disapearing anchors

--HG--
extra : rebase_source : d45fb4c2d724fe47661a24cfd505cca0dd2d8e61
extra : histedit_source : c351d519b70cbe288eeff1dac27acfcb52e907b6
Fix native assertion failure when using PrintDeoptimizationDetails in non-product build
added comment explaining insertion of nop during commoning of constant loads
Merge.
add base class for new object nodes, simplification to remove new objects without real usages
make TruffleRuntime field final
mx trufflejar: do not strip debug attributes
AlwaysValidAssumption: fix typo and make constructor private

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extra : amend_source : 70e77d83f5777a8da4cb5339025a237e12244656