[llvm] [SandboxIR][NFC] Create a DEF_CONST() macro in SandboxIRValues.def (PR #106269)

[Sriraman Tallam via llvm-commits]

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@@ -529,9 +534,15 @@ class Constant : public sandboxir::User {
 public:
   /// For isa/dyn_cast.
   static bool classof(const sandboxir::Value *From) {
-    return From->getSubclassID() == ClassID::Constant ||
-           From->getSubclassID() == ClassID::ConstantInt ||
-           From->getSubclassID() == ClassID::Function;
+    switch (From->getSubclassID()) {
+#define DEF_CONST(ID, CLASS) case ClassID::ID:
+#include "llvm/SandboxIR/SandboxIRValues.def"
+      return true;
+    case ClassID::Function:
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tmsri wrote:

DEF_CONST(Function, Function) instead?

https://github.com/llvm/llvm-project/pull/106269