[llvm] [TTI][RISCV] Add cost modelling for intrinsic vp.load.ff (PR #160470)

[Shih-Po Hung via llvm-commits]

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@@ -425,6 +425,10 @@ class RISCVTargetLowering : public TargetLowering {
   /// alignment is legal.
   bool isLegalStridedLoadStore(EVT DataType, Align Alignment) const;
 
+  /// Return true if a fault-only-first load of the given result type and
+  /// alignment is legal.
+  bool isLegalFaultOnlyFirstLoad(EVT DataType, Align Alignment) const;
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arcbbb wrote:

Good point. I considered that too.
Since the LLVM [LangRef](https://llvm.org/docs/LangRef.html) states that “ff” stands for “fault-first” or “fault-only-first,” I’d keep FaultFirst for consistency with the LangRef’s “ff” shorthand.

https://github.com/llvm/llvm-project/pull/160470