[llvm] [LoongArch] lower SCALAR_TO_VECTOR to INSERT_VECTOR_ELT (PR #122863)

[Yingchi Long via llvm-commits]

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@@ -0,0 +1,60 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc --mtriple=loongarch64 --mattr=+lsx < %s | FileCheck %s
+
+;; Test scalar_to_vector expansion.
+
+define <16 x i8> @scalar_to_16xi8(i8 %val) {
+; CHECK-LABEL: scalar_to_16xi8:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    vinsgr2vr.b $vr0, $a0, 0
+; CHECK-NEXT:    ret
+  %ret = insertelement <16 x i8> undef, i8 %val, i32 0
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inclyc wrote:

please fixup uses of `undef` by `poison`

https://github.com/llvm/llvm-project/pull/122863