[llvm] AMDGPU/GlobalISel: Lower G_EXTRACT in legalizer (PR #181036)

[via llvm-commits]

github-actions[bot] wrote:

<!--PREMERGE ADVISOR COMMENT: Windows-->
# :window: Windows x64 Test Results

* 131882 tests passed
* 2982 tests skipped
* 1 test failed

## Failed Tests
(click on a test name to see its output)

### LLVM-Unit
<details>
<summary>LLVM-Unit.CodeGen/GlobalISel/_/GlobalISelTests_exe/AArch64GISelMITest/LowerInsert</summary>

```
Script:
--
C:\_work\llvm-project\llvm-project\build\unittests\CodeGen\GlobalISel\.\GlobalISelTests.exe --gtest_filter=AArch64GISelMITest.LowerInsert
--
C:\_work\llvm-project\llvm-project\llvm\unittests\CodeGen\GlobalISel\LegalizerHelperTest.cpp:3250
Expected equality of these values:
  LegalizerHelper::LegalizeResult::UnableToLegalize
    Which is: 2
  Helper.lower(*InsertV2S32P1, 0, LLT{})
    Which is: 1


```
</details>

If these failures are unrelated to your changes (for example tests are broken or flaky at HEAD), please open an issue at https://github.com/llvm/llvm-project/issues and add the `infrastructure` label.

https://github.com/llvm/llvm-project/pull/181036