[llvm] [GlobalISel] Reject scalar sources in vector truncate combine (PR #228121)

[Maksim Shelegov via llvm-commits]

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@@ -0,0 +1,45 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 6
+# RUN: llc -mtriple=amdgpu9.00-amd-amdhsa -run-pass=amdgpu-prelegalizer-combiner -verify-machineinstrs -o - %s | FileCheck %s
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mshelego wrote:

I didn't find it at first, but there is already an existing test for this combine rule in the AArch64 target. I moved the scalar test case there.

https://github.com/llvm/llvm-project/pull/228121