[llvm] [SDAG] Convert `SDNodeFlags` into an enumeration (PR #114061)

[Krzysztof Parzyszek via llvm-commits]

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@@ -378,36 +378,46 @@ template<> struct simplify_type<SDUse> {
 /// the backend.
 struct SDNodeFlags {
 private:
-  bool NoUnsignedWrap : 1;
-  bool NoSignedWrap : 1;
-  bool Exact : 1;
-  bool Disjoint : 1;
-  bool NonNeg : 1;
-  bool NoNaNs : 1;
-  bool NoInfs : 1;
-  bool NoSignedZeros : 1;
-  bool AllowReciprocal : 1;
-  bool AllowContract : 1;
-  bool ApproximateFuncs : 1;
-  bool AllowReassociation : 1;
-
-  // We assume instructions do not raise floating-point exceptions by default,
-  // and only those marked explicitly may do so.  We could choose to represent
-  // this via a positive "FPExcept" flags like on the MI level, but having a
-  // negative "NoFPExcept" flag here makes the flag intersection logic more
-  // straightforward.
-  bool NoFPExcept : 1;
-  // Instructions with attached 'unpredictable' metadata on IR level.
-  bool Unpredictable : 1;
+  friend class SDNode;
+
+  unsigned Flags = 0;
+
+  template <unsigned Flag> void setFlag(bool B) {
+    Flags = (Flags & ~Flag) | (B ? Flag : 0);
+  }
 
 public:
+  enum {
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kparzysz wrote:

Could you make it `enum : unsigned` (or `enum : decltype(Flags)`)?

https://github.com/llvm/llvm-project/pull/114061