MC Descriptor Range Representation currently depend on Object
structures. This PR removes that dependency and in order to facilitate
removing to_underlying usage in follow-up PRs.

This pr implements support for a root signature as a target, as specified
[here](https://github.com/llvm/wg-hlsl/blob/main/proposals/0029-root-signature-driver-options.md#target-root-signature-version).

This is implemented in the following steps:
1. Add `rootsignature` as a shader model environment type and define
`rootsig` as a `target_profile`. Only valid as versions 1.0 and 1.1
2. Updates `HLSLFrontendAction` to invoke a special handling of
constructing the `ASTContext` if we are considering an `hlsl` file and
with a `rootsignature` target
3. Defines the special handling to minimally instantiate the `Parser`
and `Sema` to insert the `RootSignatureDecl`
4. Updates `CGHLSLRuntime` to emit the constructed root signature decl
as part of `dx.rootsignatures` with a `null` entry function
5. Updates `DXILRootSignature` to handle emitting a root signature
without an entry function
6. Updates `ToolChains/HLSL` to invoke `only-section=RTS0` to strip any
other generated information

Resolves: https://github.com/llvm/llvm-project/issues/150286.

##### Implementation Considerations
Ideally we could invoke this as part of `clang-dxc` without the need of
a source file. However, the initialization of the `Parser` and `Lexer`
becomes quite complicated to handle this.

Technically, we could avoid generating any of the extra information that
is removed in step 6. However, it seems better to re-use the logic in
`llvm-objcopy` without any need for additional custom logic in
`DXILRootSignature`.

fixes #157504

This changes adds the emulation we need for IsNaN, IsNormal, & IsFinite
This change only applies these emulations to the llvm.is.fpclass cases
of fp16.

Since there is no DX intrinsics yet for these cases, applying the
emulation to the necessary intrinsics is left for future implementers of
- https://github.com/llvm/llvm-project/issues/99132
- https://github.com/llvm/llvm-project/issues/156069
- https://github.com/llvm/llvm-project/issues/99131

fixes #156068

- We needed to add a new sub arch to the target tripple so we can test
that emulation does not happen when targeting SM6.9
- The HLSL toolchain needed to be updated to handle the conversion of
strings to enums for the new sub arch.
- The emulation is done in DXILIntrinsicExpansion.cpp and needs to be
able to convert both llvm.is.fpclass and lvm.dx.isinf to the proper
emulation
- test updates in TargetParser/TripleTest.cpp, isinf.ll, is_fpclass.ll,
and DXCModeTest.cpp

Changes line endings in files related to HLSL to LF (`\n`).

fixes #152348

SimplifyCFG collapses raw buffer store from a if\else load into a
select.

This change prevents the TargetExtType dx.Rawbuffer from being replace
thus preserving the if\else blocks.

A further change was needed to eliminate the phi node before we process
Intrinsic::dx_resource_getpointer in DXILResourceAccess.cpp

Remove all "approx-func-fp-math" in tests.

DXC checks if registers are correctly bound to root signature
descriptors. This implements the same check.
closes: #[126645](https://github.com/llvm/llvm-project/issues/126645)

---------

Co-authored-by: joaosaffran <joao.saffran@microsoft.com>
Co-authored-by: Joao Saffran <jderezende@microsoft.com>

Removes uniformity bit from resource initialization intrinsics `llvm.{dx|spv}.resource.handlefrombinding` and `llvm.{dx|spv}.resource.handlefromimplicitbinding`. The flag currently always set to `false`. It should be derived from resource analysis and not provided by codegen.

Closes #135452

This pr fixes some inconsistencies in behaviour of how we handle
`StaticSamplersOffset` with respect to DXC and `RootParameterOffset`.
Namely:

1. Make codegen of `RTS0` always compute the `StaticSamplersOffset`
regardless if there are any `StaticSampler`s. This is to be consistent
and produce an identical `DXContainer` as DXC.
2. Make the `StaticSamplersOffset` and `RootParametersOffset` optional
parameters in the yaml description. This means it will be used when it
is specified (which was not necassarily the case before).
3. Enforce that the provided `StaticSamplersOffset` and
`RootParametersOffset` in a yaml description match the computed value.

For more context see:
https://github.com/llvm/llvm-project/issues/155299.

Description of existing test updates updates:
- `CodeGen/DirectX/ContainerData`: Updated to codegen computed values
(previously unspecified)
- `llvm-objcopy/DXContainer`: Updated to `yaml2obj` computed values
(previously unspecified)
- `ObjectYAML/DXContainer`: Updated to `yaml2obj` computed values
(previously incorrect)
- `ObjectYAML/DXContainerYAMLTest`: Updated to `yaml2obj` computed
values (previously incorrect)

See newly added tests for testing of optional parameter functionality
and `StaticSamplersOffset` computation.

Resolves: https://github.com/llvm/llvm-project/issues/155299