DXC produces invalid DXIL on dot using argument with double type.

[python3kgae]

Description
dot(a, b) will generate invalid DXIL when a and b are vectors of double.
The hlsl intrinsic allows double vector while the dxil op for dot not support double.
Steps to Reproduce

dxc -Tps_6_0

double2 a;
double2 b;

float main() : SV_Target {
return dot(a, b);
}

Actual Behavior

DXC generated DXIL that failed validation.
Environment

• DXC version : 1.8
• Host Operating System : Windows

[tex3d]

To be clear, the crash is a temporary regression in the main branch and original 1.8 release that was fixed in point release. The prior behavior, the current behavior of latest 1.8 releases, and the behavior for main once #6543 merges, will be to produce a validation error due to an illegal DXIL op overload instead.

[damyanp]

We have no plans to make changes in this area in DXC without considering a design that takes into account what the design is in Clang. For this reason I'm closing this issue as not planned.