Backed out changeset: edb2e6bd6a01 (superseded by ce5e6f9075b6)
Truffle: fix possible node rewrite failures after recursive calls.

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extra : transplant_source : w%CBC%F1%8BF%1B%B9Ola%24%3C%E6%92%C7%FAa%5C%B6
Truffle: add sanity check.

--HG--
extra : amend_source : 0b2110f199cb39d1452cc78bf43a6d9a7d7aa81a
extra : transplant_source : %CD%FD0%82%89%88%22V%B1%2Bl%82%B5%FA%CD%82x0%C8%C4
FloatingReadNode: simplify assert condition
gate: clean and build IGV (not GV)
Flush deferred barrier when Graal and G1 are used
Merge
workaround for bug in Clang 5.0
added limited ability for one HotSpotBackendFactory to override another
added support code for Truffle to inject special tail-call code into the prefix of OptimizedCallTarget.call(PackedFrame, Arguments)
Add NeverInlineMacro for OptimizedCallTarget.call
minor reformatting based on 'mx eclipseformat'
applied autoformat
Merge.
Allow CodeCacheProvider to install default methods
enable zero-count metrics to be shown (disable with new -G:+SuppressZeroDebugValues option)
moved snippet timers/metrics from SnippetTemplate to SnippetInfo and added new metric for number of snippet specializations (i.e. number of SnippetTemplate objects created)
mxtool: handle missing hg executable gracefully
mxtool sclone: check import version when imported suite already exists
Disable deferred init barriers