[llvm] [DirectX] Set shader feature flags MinimumPrecision and NativeLowPrecision, and refactor the logic for setting low-precision-related flags (PR #139623)

[Deric C. via llvm-commits]

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@@ -91,7 +91,10 @@ struct ModuleShaderFlags {
   const ComputedShaderFlags &getCombinedFlags() const { return CombinedSFMask; }
 
 private:
-  bool CanSetResMayNotAlias;
+  // Booleans set by module flags
+  bool CanSetResMayNotAlias;   // dx.resmayalias
+  bool NativeLowPrecisionMode; // dx.nativelowprec
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Icohedron wrote:

I think `CanSetNativeLowPrecisionMode` would make more sense

https://github.com/llvm/llvm-project/pull/139623