[clang] [CIR][CodeGen] Upstream support for FP environments and RAII options (PR #179121)

[Andy Kaylor via cfe-commits]

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@@ -106,6 +111,57 @@ class CIRGenBuilderTy : public cir::CIRBaseBuilderTy {
     return baseName + "." + std::to_string(recordNames[baseName]++);
   }
 
+  //
+  // Floating point specific helpers
+  // -------------------------------
+  //
+
+  /// Enable/Disable use of constrained floating point math. When enabled the
+  /// CreateF<op>() calls instead create constrained floating point intrinsic
+  /// calls. Fast math flags are unaffected by this setting.
+  void setIsFPConstrained(bool IsCon) {
+    if (IsCon)
+      llvm_unreachable("Constrained FP NYI");
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andykaylor wrote:

This seems unnecessary. There's nothing special we need to implement here. A diagnostic should be introduced wherever this is used, not here.

https://github.com/llvm/llvm-project/pull/179121