[HLSL] Diagnostics for semantic annotations

[llvm-beanz]

Description

This issue tracks all-up diagnostics for semantic annotations. We need to identify all the parts of this.

For example:

In HLSL there are certain combinations of semantics that are valid for inputs and outputs of shaders as defined by the shader stage. @bob80905 began writing a proposal for how we can perform this analysis and verification during semantic analysis: microsoft/hlsl-specs#156

Acceptance Criteria

Implement robust diagnostic for combinations of semantics on inputs and outputs as defined in the specification above.

Sub tasks

• Scope and define this task

[damyanp]

See this DXC bug that has some cases that should be considered here: microsoft/DirectXShaderCompiler#3508