## Changes
- Delete DirectX length intrinsic
- Delete HLSL length lang builtin
- Implement length algorithm entirely in the header.
## History
- In the past if an HLSL intrinsic lowered to either a spirv op code or
a DXIL opcode we represented it with intrinsics
## Why we are moving away?
- To make HLSL apis more portable the team decided that it makes sense
for some intrinsics to be defined only in the header.
- Since there tends to be more SPIRV opcodes than DXIL opcodes the plan
is to support SPIRV opcodes either with target specific builtins or via
pattern matching.