[llvm] [TableGen] Refactor Intrinsics record (PR #106986)

[Rahul Joshi via llvm-commits]

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@@ -273,11 +273,12 @@ using TypeSigTy = SmallVector<unsigned char>;
 /// Computes type signature of the intrinsic \p Int.
 static TypeSigTy ComputeTypeSignature(const CodeGenIntrinsic &Int) {
   TypeSigTy TypeSig;
-  if (const auto *R = Int.TheDef->getValue("TypeSig")) {
-    for (const auto *a : cast<ListInit>(R->getValue())->getValues()) {
-      for (const auto *b : cast<ListInit>(a)->getValues())
-        TypeSig.emplace_back(cast<IntInit>(b)->getValue());
-    }
+  const Record *TypeInfo = Int.TheDef->getValueAsDef("TypeInfo");
+  const ListInit *OuterList = TypeInfo->getValueAsListInit("TypeSig");
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jurahul wrote:

That I don't understand. Isn't a particular emitter tightly coupled with the corresponding TableGen record structure? For example, code in `CodeGenIntrinsic.cpp` assumes that all Intrinsic records have fields TargetPrefix and LLVMName. In the same vein, this code assumes that it has a `TypeInfo` field.

https://github.com/llvm/llvm-project/pull/106986