[llvm] [AMDGPU][MIR] Serialize NumPhysicalVGPRSpillLanes (PR #115291)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `lld-x86_64-ubuntu-fast` running on `as-builder-4` while building `llvm` at step 6 "test-build-unified-tree-check-all".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/33/builds/6047

<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 :: CodeGen/MIR/AMDGPU/machine-function-info.ll' FAILED ********************
Exit Code: 1

Command Output (stderr):
--
RUN: at line 1: /home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/build/bin/llc -mtriple=amdgcn-mesa-mesa3d -mcpu=tahiti -stop-after=si-pre-allocate-wwm-regs -o /home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/build/test/CodeGen/MIR/AMDGPU/Output/machine-function-info.ll.tmp.mir /home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/llvm-project/llvm/test/CodeGen/MIR/AMDGPU/machine-function-info.ll
+ /home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/build/bin/llc -mtriple=amdgcn-mesa-mesa3d -mcpu=tahiti -stop-after=si-pre-allocate-wwm-regs -o /home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/build/test/CodeGen/MIR/AMDGPU/Output/machine-function-info.ll.tmp.mir /home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/llvm-project/llvm/test/CodeGen/MIR/AMDGPU/machine-function-info.ll
RUN: at line 2: /home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/build/bin/llc -run-pass=none -verify-machineinstrs /home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/build/test/CodeGen/MIR/AMDGPU/Output/machine-function-info.ll.tmp.mir -o - | /home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/build/bin/FileCheck /home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/llvm-project/llvm/test/CodeGen/MIR/AMDGPU/machine-function-info.ll
+ /home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/build/bin/llc -run-pass=none -verify-machineinstrs /home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/build/test/CodeGen/MIR/AMDGPU/Output/machine-function-info.ll.tmp.mir -o -
+ /home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/build/bin/FileCheck /home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/llvm-project/llvm/test/CodeGen/MIR/AMDGPU/machine-function-info.ll
/home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/llvm-project/llvm/test/CodeGen/MIR/AMDGPU/machine-function-info.ll:51:15: error: CHECK-NEXT: is not on the line after the previous match
; CHECK-NEXT: vgprForAGPRCopy: ''
              ^
<stdin>:228:2: note: 'next' match was here
 vgprForAGPRCopy: ''
 ^
<stdin>:226:14: note: previous match ended here
 occupancy: 8
             ^
<stdin>:227:1: note: non-matching line after previous match is here
 numPhysicalVGPRSpillLanes: 0
^
/home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/llvm-project/llvm/test/CodeGen/MIR/AMDGPU/machine-function-info.ll:97:15: error: CHECK-NEXT: is not on the line after the previous match
; CHECK-NEXT: vgprForAGPRCopy: ''
              ^
<stdin>:339:2: note: 'next' match was here
 vgprForAGPRCopy: ''
 ^
<stdin>:337:15: note: previous match ended here
 occupancy: 10
              ^
<stdin>:338:1: note: non-matching line after previous match is here
 numPhysicalVGPRSpillLanes: 0
^
/home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/llvm-project/llvm/test/CodeGen/MIR/AMDGPU/machine-function-info.ll:167:15: error: CHECK-NEXT: is not on the line after the previous match
; CHECK-NEXT: vgprForAGPRCopy: ''
              ^
<stdin>:666:2: note: 'next' match was here
 vgprForAGPRCopy: ''
 ^
<stdin>:664:14: note: previous match ended here
 occupancy: 8
             ^
<stdin>:665:1: note: non-matching line after previous match is here
 numPhysicalVGPRSpillLanes: 0
^
/home/buildbot/worker/as-builder-4/ramdisk/lld-x86_64/llvm-project/llvm/test/CodeGen/MIR/AMDGPU/machine-function-info.ll:219:15: error: CHECK-NEXT: is not on the line after the previous match
; CHECK-NEXT: vgprForAGPRCopy: ''
              ^
<stdin>:778:2: note: 'next' match was here
...

```

</details>

https://github.com/llvm/llvm-project/pull/115291