[llvm] [RISCV] Mark RVV stores and some loads as masked pseudo (PR #123106)

[Luke Lau via llvm-commits]

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@@ -3829,8 +3830,9 @@ bool RISCVDAGToDAGISel::doPeepholeMaskedRVV(MachineSDNode *N) {
 #endif
 
   SmallVector<SDValue, 8> Ops;
-  // Skip the passthru operand at index 0 if !UseTUPseudo and no GPR out.
-  bool ShouldSkip = !UseTUPseudo && !hasGPROut(Opc);
+  // Skip the passthru operand at index 0 if !UseTUPseudo and has the passthru
+  // operand.
+  bool ShouldSkip = !UseTUPseudo && hasPassthru(MCID);
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lukel97 wrote:

I thought it was weird that we were using the vec policy op to determine if the unmasked pseudo had a passthru operand, so I fixed it to use `isFirstDefTiedToFirstUse` and remove `hasGPROut` in ec5d17b58779e2fb08a7c9c706b2842586f71f78, can you rebase on top of it and check if it works for stores now?

https://github.com/llvm/llvm-project/pull/123106