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

[Matt Arsenault 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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arsenm 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 

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