[llvm] [SelectionDAG] Virtualize isTargetStrictFPOpcode / isTargetMemoryOpcode (PR #119969)

[Sergey Barannikov via llvm-commits]

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@@ -35,6 +35,19 @@ class SelectionDAGTargetInfo {
   SelectionDAGTargetInfo &operator=(const SelectionDAGTargetInfo &) = delete;
   virtual ~SelectionDAGTargetInfo();
 
+  /// Returns true if a node with the given target-specific opcode has
+  /// a memory operand. Nodes with such opcodes can only be created with
+  /// `SelectionDAG::getMemIntrinsicNode`.
+  virtual bool isTargetMemoryOpcode(unsigned Opcode) const { return false; }
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s-barannikov wrote:

I also see this class as a place for [autogenerated] target-specific queries like RISCV's [hasPassThruOp](https://github.com/llvm/llvm-project/pull/119709/files#diff-c179575972a6aa579b04129e1a96a4c1f4ac0dc457c0f647150eed1b54b5a861R58) (will take some time to scroll to the definition).


https://github.com/llvm/llvm-project/pull/119969