[llvm] [DirectX] Propagate shader flags mask of callees to callers (PR #118306)

[Chris B via llvm-commits]

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@@ -95,6 +95,8 @@ struct ModuleShaderFlags {
   SmallVector<std::pair<Function const *, ComputedShaderFlags>> FunctionFlags;
   /// Combined Shader Flag Mask of all functions of the module
   ComputedShaderFlags CombinedSFMask{};
+  auto getFunctionShaderFlagInfo(const Function *) const;
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llvm-beanz wrote:

LLVM has an "almost never `auto`" policy. We should only use `auto` where it makes code easier to read and where types are obvious from other context. That is not the case here.

see: https://llvm.org/docs/CodingStandards.html#use-auto-type-deduction-to-make-code-more-readable

https://github.com/llvm/llvm-project/pull/118306