https://issues.dlang.org/show_bug.cgi?id=12849

          Issue ID: 12849
           Summary: pmovmskb instruction cannot store to 64-bit registers
           Product: D
           Version: D2
          Hardware: x86_64
                OS: All
            Status: NEW
          Severity: normal
          Priority: P1
         Component: DMD
          Assignee: nobody@puremagic.com
          Reporter: briancschott@gmail.com

void main()
{
    ulong a = 0xff;
    ulong b;
    asm
    {
        movq XMM0, a;
        pmovmskb RAX, XMM0;
        mov b, RAX;
    }
    assert (b == 1);
}

bug.d(8): Error: bad type/size of operands 'pmovmskb'

This is perfectly valid according to the Intel documentation.

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