fix Issue 12838 - Dmd show ICEs when using Tuple and wrong type
Fix issue 12849: pmovmskb instruction cannot store to 64-bit registers
Another attempt at understanding these constants
Add unit test for 64-bit pmovmskb
Merge pull request #3621 from Hackerpilot/issue-12849

Fix issue 12849: pmovmskb instruction cannot store to 64-bit registers
Merge pull request #3617 from 9rnsr/fix12838

Issue 12838 - Dmd show ICEs when using Tuple and wrong type