[llvm] [TableGen] Speed up intrinsic lookups with DenseMap (NFC) (PR #213198)

[Manasij Mukherjee via llvm-commits]

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@@ -1155,10 +1157,9 @@ class CodeGenDAGPatterns {
   }
 
   const CodeGenIntrinsic &getIntrinsic(const Record *R) const {
-    for (const CodeGenIntrinsic &Intrinsic : Intrinsics)
-      if (Intrinsic.TheDef == R)
-        return Intrinsic;
-    llvm_unreachable("Unknown intrinsic!");
+    auto I = IntrinsicIDs.find(R);
+    assert(I != IntrinsicIDs.end() && "Unknown intrinsic!");
+    return Intrinsics[I->second];
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manasij7479 wrote:

Done

https://github.com/llvm/llvm-project/pull/213198