4 day week.

[TCWG-1424] Investigate profile feedback on codesize Have now got all the data I need, started the process of tidying up scripts to analyse whether it is worth posting upstream and what the best default parameters are.

[Misc] Track down problem on AArch64 build-bot to a likely code-gen problem in Clang 3.8 for AArch64 only. Wrote a patch to use clang 6.0 on all the Linaro buildbots rather than just the libcxx builder. Will hopefully get deployed next week.

[LLD] Work on adding support for EF_ARM_ABI_FLOAT_HARD and EF_ARM_ABI_FLOAT_SOFT Needed to unblock freebsd from moving onto trunk Mostly done, just need to finish adding tests. Might be a good jumping off point to implement full build attributes support.