[llvm] [SPIR-V] Implement SPV_KHR_float_controls2 (PR #146941)

[Nathan Gauër via llvm-commits]

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@@ -262,6 +264,33 @@ class SPIRVEmitIntrinsics
   }
 };
 
+struct FPFastMathDefaultInfo {
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Keenuts wrote:

This is an exact copy of the FPFastMathDefaultInfo struct in the ModuleAnalysis? Why not reuse it?

https://github.com/llvm/llvm-project/pull/146941