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

[Andy Kaylor via cfe-commits]

================
@@ -106,6 +111,43 @@ 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) { isFPConstrained = isCon; }
+
+  /// Query for the use of constrained floating point math
+  const bool getIsFPConstrained() { return isFPConstrained; }
----------------
andykaylor wrote:

```suggestion
  bool getIsFPConstrained() const { return isFPConstrained; }
```

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