[llvm] [IR] Initial introduction of memset_pattern (PR #97583)

[Craig Topper via llvm-commits]

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@@ -1263,6 +1263,46 @@ class MemSetInlineInst : public MemSetInst {
   }
 };
 
+/// This is the base class for memset.pattern
+class MemSetPatternIntrinsic : public MemIntrinsicBase<MemIntrinsic> {
+private:
+  enum { ARG_VOLATILE = 3 };
+
+public:
+  ConstantInt *getVolatileCst() const {
+    return cast<ConstantInt>(const_cast<Value *>(getArgOperand(ARG_VOLATILE)));
+  }
+
+  bool isVolatile() const { return !getVolatileCst()->isZero(); }
+
+  void setVolatile(Constant *V) { setArgOperand(ARG_VOLATILE, V); }
+
+  // Methods for support of type inquiry through isa, cast, and dyn_cast:
+  static bool classof(const IntrinsicInst *I) {
+    switch (I->getIntrinsicID()) {
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topperc wrote:

`return I->getIntrinsicID() == Intrinsic::experimental_memset_pattern`?

https://github.com/llvm/llvm-project/pull/97583