[llvm] AMDGPU: Match and Select BITOP3 on gfx950 (PR #117843)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `llvm-clang-x86_64-expensive-checks-debian` running on `gribozavr4` while building `llvm` at step 6 "test-build-unified-tree-check-all".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/16/builds/9699

<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/AMDGPU/bitop3.ll' FAILED ********************
Exit Code: 1

Command Output (stderr):
--
RUN: at line 2: /b/1/llvm-clang-x86_64-expensive-checks-debian/build/bin/llc -march=amdgcn -mcpu=gfx950 < /b/1/llvm-clang-x86_64-expensive-checks-debian/llvm-project/llvm/test/CodeGen/AMDGPU/bitop3.ll | /b/1/llvm-clang-x86_64-expensive-checks-debian/build/bin/FileCheck -enable-var-scope -check-prefixes=GCN,GFX950,GFX950-SDAG /b/1/llvm-clang-x86_64-expensive-checks-debian/llvm-project/llvm/test/CodeGen/AMDGPU/bitop3.ll
+ /b/1/llvm-clang-x86_64-expensive-checks-debian/build/bin/llc -march=amdgcn -mcpu=gfx950
+ /b/1/llvm-clang-x86_64-expensive-checks-debian/build/bin/FileCheck -enable-var-scope -check-prefixes=GCN,GFX950,GFX950-SDAG /b/1/llvm-clang-x86_64-expensive-checks-debian/llvm-project/llvm/test/CodeGen/AMDGPU/bitop3.ll
RUN: at line 3: /b/1/llvm-clang-x86_64-expensive-checks-debian/build/bin/llc -global-isel -march=amdgcn -mcpu=gfx950 < /b/1/llvm-clang-x86_64-expensive-checks-debian/llvm-project/llvm/test/CodeGen/AMDGPU/bitop3.ll | /b/1/llvm-clang-x86_64-expensive-checks-debian/build/bin/FileCheck -enable-var-scope -check-prefixes=GCN,GFX950,GFX950-GISEL /b/1/llvm-clang-x86_64-expensive-checks-debian/llvm-project/llvm/test/CodeGen/AMDGPU/bitop3.ll
+ /b/1/llvm-clang-x86_64-expensive-checks-debian/build/bin/llc -global-isel -march=amdgcn -mcpu=gfx950
+ /b/1/llvm-clang-x86_64-expensive-checks-debian/build/bin/FileCheck -enable-var-scope -check-prefixes=GCN,GFX950,GFX950-GISEL /b/1/llvm-clang-x86_64-expensive-checks-debian/llvm-project/llvm/test/CodeGen/AMDGPU/bitop3.ll

# After Eliminate PHI nodes for register allocation
# Machine code for function uniform_4_op: NoPHIs, TracksLiveness, Legalized, RegBankSelected, Selected

bb.0 (%ir-block.0):
  liveins: $sgpr0, $sgpr1, $sgpr2
  %0:sreg_32 = COPY killed $sgpr0
  %1:sreg_32 = COPY killed $sgpr1
  %2:sreg_32 = COPY killed $sgpr2
  %8:vgpr_32 = COPY killed %1:sreg_32
  %9:vgpr_32 = COPY killed %2:sreg_32
  %10:vgpr_32 = V_BITOP3_B32_e64 killed %0:sreg_32, killed %8:vgpr_32, killed %9:vgpr_32, 2, implicit $exec
  %7:sreg_32 = COPY killed %10:vgpr_32
  $vgpr0 = COPY killed %7:sreg_32
  SI_RETURN_TO_EPILOG implicit killed $vgpr0

# End machine code for function uniform_4_op.

*** Bad machine code: illegal copy from vector register to SGPR ***
- function:    uniform_4_op
- basic block: %bb.0  (0x9680cc8)
- instruction: %7:sreg_32 = COPY killed %10:vgpr_32
LLVM ERROR: Found 1 machine code errors.
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace.
Stack dump:
0.	Program arguments: /b/1/llvm-clang-x86_64-expensive-checks-debian/build/bin/llc -global-isel -march=amdgcn -mcpu=gfx950
1.	Running pass 'CallGraph Pass Manager' on module '<stdin>'.
2.	Running pass 'Verify generated machine code' on function '@uniform_4_op'
 #0 0x000000000365fe07 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/b/1/llvm-clang-x86_64-expensive-checks-debian/build/bin/llc+0x365fe07)
 #1 0x000000000365d8be llvm::sys::RunSignalHandlers() (/b/1/llvm-clang-x86_64-expensive-checks-debian/build/bin/llc+0x365d8be)
 #2 0x00000000036604bf SignalHandler(int) Signals.cpp:0:0
 #3 0x00007fa3da164140 __restore_rt (/lib/x86_64-linux-gnu/libpthread.so.0+0x13140)
 #4 0x00007fa3d9c78d51 raise (/lib/x86_64-linux-gnu/libc.so.6+0x38d51)
 #5 0x00007fa3d9c62537 abort (/lib/x86_64-linux-gnu/libc.so.6+0x22537)
 #6 0x00000000035d0e7a llvm::report_fatal_error(llvm::Twine const&, bool) (/b/1/llvm-clang-x86_64-expensive-checks-debian/build/bin/llc+0x35d0e7a)
 #7 0x000000000286852a (/b/1/llvm-clang-x86_64-expensive-checks-debian/build/bin/llc+0x286852a)
 #8 0x0000000002869508 (anonymous namespace)::MachineVerifierLegacyPass::runOnMachineFunction(llvm::MachineFunction&) MachineVerifier.cpp:0:0
 #9 0x000000000276b510 llvm::MachineFunctionPass::runOnFunction(llvm::Function&) (/b/1/llvm-clang-x86_64-expensive-checks-debian/build/bin/llc+0x276b510)
#10 0x0000000002cb4364 llvm::FPPassManager::runOnFunction(llvm::Function&) (/b/1/llvm-clang-x86_64-expensive-checks-debian/build/bin/llc+0x2cb4364)
...

```

</details>

https://github.com/llvm/llvm-project/pull/117843