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

[Luke Lau via llvm-commits]

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@@ -1616,6 +1616,11 @@ class TargetTransformInfo {
       TTI::TargetCostKind CostKind = TTI::TCK_RecipThroughput,
       bool UseMaskForCond = false, bool UseMaskForGaps = false) const;
 
+  /// \return The cost of vp intrinsic vp.load.ff.
+  LLVM_ABI InstructionCost getFirstFaultLoadCost(
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lukel97 wrote:

TIL that `getVPMemoryOpCost` actually exists. We don't use it in RISC-V, so it looks like it's dead. I've opened up a PR to remove it: https://github.com/llvm/llvm-project/pull/160838

Given that we're moving away from VP intrinsics in general, if SVE ever wants to support first-fault loads I presume we'll want to have a non-VP hook anyway?

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