[llvm] [LoongArch] Pre-commit test for loop term fold pass & vector sext, zext (PR #131742)

[Lu Weining via llvm-commits]

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@@ -0,0 +1,246 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc --mtriple=loongarch64 --mattr=+d,+lsx < %s | FileCheck %s
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SixWeining wrote:

```suggestion
; RUN: llc --mtriple=loongarch64 --mattr=+lsx < %s | FileCheck %s
```

https://github.com/llvm/llvm-project/pull/131742