[llvm] [RISCV][CostModel][NFC] Add getRISCVInstructionCost() to TTI for Cost… (PR #73651)

[Craig Topper via llvm-commits]

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@@ -387,7 +446,12 @@ InstructionCost RISCVTTIImpl::getShuffleCost(TTI::ShuffleKind Kind,
         //   vsetivli zero, 2, e8, mf8, ta, ma (ignored)
         //   vmv.v.x v8, a0
         //   vmsne.vi v0, v8, 0
-        return LT.first * TLI->getLMULCost(LT.second) * 3;
+        return LT.first *
+               (TLI->getLMULCost(LT.second) + // FIXME: should be 1 for andi
+                getRISCVInstructionCost(RISCVInstruction::VMV, LT.second, 1,
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topperc wrote:

RISCVInstruction::VMV seems to be used for different instruction here and on line 434. Line 434 uses it for vmv.s.x which is an operation that doesn't use LMUL. This code uses it for vmv.v.v which does use LMUL.

https://github.com/llvm/llvm-project/pull/73651