This pr relands https://github.com/llvm/llvm-project/pull/133302.
It resolves two issues:
- Linking error during build,
[here](https://github.com/llvm/llvm-project/pull/133302#issuecomment-2767259848).
There was a missing dependency for `clangLex` for the
`ParseHLSLRootSignatureTest.cpp` unit testing. This library was added to
the dependencies to resolve the error. It wasn't caught previously as
the library was transitively linked in most build environments
- Warning of unused declaration,
[here](https://github.com/llvm/llvm-project/pull/133302#issuecomment-2767091368).
There was a usability line in `LexHLSLRootSignature.h` of the form
`using TokenKind = enum RootSignatureToken::Kind` which causes this
error. The declaration is removed from the header file to be used
locally in the `.cpp` files that use it.
Notably, the original pr would also exposed `clang::hlsl::TokenKind` to
everywhere it was included, which had a name clash with
`tok::TokenKind`. This is another motivation to change to the proposed
resolution.
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Co-authored-by: Finn Plummer <finnplummer@microsoft.com>
From the corrections to the Root Signature specification here:
https://github.com/llvm/wg-hlsl/issues/192. It was denoted that keywords
are also case-insensitive in DXC.
This pr adjusts the lexer to adhere to the updated spec.
We also have a NFC to add a missing license to a file while in the area.
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Co-authored-by: Finn Plummer <finnplummer@microsoft.com>
For the sake of scope, we will let the lexing of floating literals be
deferred until needed for Static Samplers. Other than that this pr
should allow us to simply define new enumerations/keywords in
`RootSignatureTokenKinds.def` for when they are used in the parser. We
could have defined all of these keywords here, but for the sake of
correctness in review we will let them be split up.
- Define `RootSignatureLexer` and provide a public `LexToken` method for
external use
- Define the file `RootSignatureTokenKinds` to define required tokens
and allow for future custom keywords/enums
- Implement the internal methods required to parse the different types
of tokens (integers, flag enums, puncuators...)
- Add test harness for unit testing and the respective unit tests for
lexing the tokens
Resolves#126563
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Co-authored-by: Chris B <beanz@abolishcrlf.org>
