This implements c2 and runtime support to pass a reference to an existing buffer, if there's one, as part of the scalarized calling convention. The buffer reference and the null marker are both always passed at this point.
------------- Commit messages: - whitespaces - test tweaks - more - aarch64 - more - more - more - fix & test - undo bad fix - more - ... and 11 more: https://git.openjdk.org/valhalla/compare/186c02e8...2dd1732b Changes: https://git.openjdk.org/valhalla/pull/2062/files Webrev: https://webrevs.openjdk.org/?repo=valhalla&pr=2062&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8372268 Stats: 492 lines in 24 files changed: 447 ins; 12 del; 33 mod Patch: https://git.openjdk.org/valhalla/pull/2062.diff Fetch: git fetch https://git.openjdk.org/valhalla.git pull/2062/head:pull/2062 PR: https://git.openjdk.org/valhalla/pull/2062
