[llvm] [AArch64][GlobalISel] Add support for widening vector store elements to s8. (PR #121170)

[Amara Emerson via llvm-commits]

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@@ -0,0 +1,32 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 5
+# RUN: llc -O0 -mtriple=aarch64 -run-pass=legalizer -global-isel-abort=2 %s -o - | FileCheck %s
+# This test currently is expected to fall back after reaching truncstore of <8 x s8> as <8 x s1>.
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aemerson wrote:

> This is a fragile way of testing this fallback case (testing fallback in a single pass MIR test is also odd). Should check the fallback error message, unless you're just going to fix this in the next commit anyway

Yeah this is going to be immediately fixed in the follow ups.

https://github.com/llvm/llvm-project/pull/121170