cannot slice xmm rvalue

[WalterBright]

Attempting to slice a vector register rvalue results in bad code generation.

[dlang-bot]

Thanks for your pull request, @WalterBright!

Bugzilla references

Auto-close	Bugzilla	Severity	Description
✗	19788	normal	compiler crash on slicing a enum typed as vector

Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub run digger -- build "master + dmd#14580"

[WalterBright]

Fixing incorrect solution #12043

[ljmf00]

Fixing incorrect solution #12043

Reference the issue in the commit, so the bot can cross reference it with the issue tracker.

[WalterBright]

@ljmf00 ok