[llvm] [PHIElim][AMDGPU]: shrink source subranges to lane-specific uses (PR #228073)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `llvm-clang-aarch64-darwin` running on `doug-worker-5` while building `llvm` at step 6 "test-build-unified-tree-check-all".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/190/builds/51078

<details>
<summary>Here is the relevant piece of the build log for the reference</summary>

```
Step 6 (test-build-unified-tree-check-all) failure: test (failure)
******************** TEST 'LLVM :: Transforms/IRNormalizer/naming-args-instr-blocks.ll' FAILED ********************
Exit Code: 2

Command Output (stdout):
--
# RUN: at line 2
/Volumes/ExternalSSD/buildbot-root/aarch64-darwin/build/bin/opt -S -passes=normalize < /Users/buildbot/buildbot-root2/aarch64-darwin/llvm-project/llvm/test/Transforms/IRNormalizer/naming-args-instr-blocks.ll | /Volumes/ExternalSSD/buildbot-root/aarch64-darwin/build/bin/FileCheck /Users/buildbot/buildbot-root2/aarch64-darwin/llvm-project/llvm/test/Transforms/IRNormalizer/naming-args-instr-blocks.ll
# executed command: /Volumes/ExternalSSD/buildbot-root/aarch64-darwin/build/bin/opt -S -passes=normalize
# note: command had no output on stdout or stderr
# error: command failed with exit status: -6
# executed command: /Volumes/ExternalSSD/buildbot-root/aarch64-darwin/build/bin/FileCheck /Users/buildbot/buildbot-root2/aarch64-darwin/llvm-project/llvm/test/Transforms/IRNormalizer/naming-args-instr-blocks.ll
# .---command stderr------------
# | FileCheck error: '<stdin>' is empty.
# | FileCheck command line:  /Volumes/ExternalSSD/buildbot-root/aarch64-darwin/build/bin/FileCheck /Users/buildbot/buildbot-root2/aarch64-darwin/llvm-project/llvm/test/Transforms/IRNormalizer/naming-args-instr-blocks.ll
# `-----------------------------
# error: command failed with exit status: 2

--

********************


```

</details>

https://github.com/llvm/llvm-project/pull/228073