LDC 1.5-1.6 huge degradation of optimization

[kinke]

On Thursday, 30 November 2017 at 15:25:31 UTC, Igor Shirkalin 
wrote:
> It's now obvious the reason of this regression is LLVM 5.0.0
> Does it mean it's not time to move to latest LLVM for the 
> latest LDC?

5.0.0 *is* the latest released version. 5.0.1 is about to be 
released these days, but whether it'll fix this issue is 
uncertain. As is whether it's fixed in current LLVM master 
(6.0.0). LLVM is a huge piece of software, bugs and regressions 
are to be expected.