[llvm] [RISCV] Support `llvm.masked.compressstore` intrinsic (PR #83457)

[Craig Topper via llvm-commits]

================
@@ -1609,3 +1609,10 @@ bool RISCVTTIImpl::isLSRCostLess(const TargetTransformInfo::LSRCost &C1,
                   C2.NumIVMuls, C2.NumBaseAdds,
                   C2.ScaleCost, C2.ImmCost, C2.SetupCost);
 }
+
+bool RISCVTTIImpl::isLegalMaskedCompressStore(Type *DataTy) {
----------------
topperc wrote:

Once we fix the alignment for the intrinsic we'll also need to teach ScalarMaskedMemIntrinsic to preserve it when scalarizing.

https://github.com/llvm/llvm-project/pull/83457