[llvm] [AArch64] Lower scalable i1 vector add reduction to cntp (PR #99031)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `clang-debian-cpp20` running on `clang-debian-cpp20` while building `llvm` at step 6 "test-build-unified-tree-check-all".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/108/builds/1547

Here is the relevant piece of the build log for the reference:
```
Step 6 (test-build-unified-tree-check-all) failure: test (failure)
******************** TEST 'LLVM :: CodeGen/AArch64/sve-i1-add-reduce.ll' FAILED ********************
Exit Code: 2

Command Output (stderr):
--
RUN: at line 2: /vol/worker/clang-debian-cpp20/clang-debian-cpp20/build/bin/llc -mtriple=aarch64-linux-gnu -mattr=+sve < /vol/worker/clang-debian-cpp20/clang-debian-cpp20/llvm-project/llvm/test/CodeGen/AArch64/sve-i1-add-reduce.ll | /vol/worker/clang-debian-cpp20/clang-debian-cpp20/build/bin/FileCheck /vol/worker/clang-debian-cpp20/clang-debian-cpp20/llvm-project/llvm/test/CodeGen/AArch64/sve-i1-add-reduce.ll
+ /vol/worker/clang-debian-cpp20/clang-debian-cpp20/build/bin/llc -mtriple=aarch64-linux-gnu -mattr=+sve
+ /vol/worker/clang-debian-cpp20/clang-debian-cpp20/build/bin/FileCheck /vol/worker/clang-debian-cpp20/clang-debian-cpp20/llvm-project/llvm/test/CodeGen/AArch64/sve-i1-add-reduce.ll
LLVM ERROR: Cannot select: t14: nxv2i64 = AArch64ISD::UADDV_PRED t10, t2
  t10: nxv16i1 = AArch64ISD::PTRUE TargetConstant:i32<31>
    t9: i32 = TargetConstant<31>
  t2: nxv16i1,ch = CopyFromReg t0, Register:nxv16i1 %0
    t1: nxv16i1 = Register %0
In function: uaddv_zexti8_nxv16i1
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace.
Stack dump:
0.	Program arguments: /vol/worker/clang-debian-cpp20/clang-debian-cpp20/build/bin/llc -mtriple=aarch64-linux-gnu -mattr=+sve
1.	Running pass 'Function Pass Manager' on module '<stdin>'.
2.	Running pass 'AArch64 Instruction Selection' on function '@uaddv_zexti8_nxv16i1'
 #0 0x00005802f2a6c098 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/vol/worker/clang-debian-cpp20/clang-debian-cpp20/build/bin/llc+0x34e6098)
 #1 0x00005802f2a69b0d llvm::sys::RunSignalHandlers() (/vol/worker/clang-debian-cpp20/clang-debian-cpp20/build/bin/llc+0x34e3b0d)
 #2 0x00005802f2a6c638 SignalHandler(int) Signals.cpp:0:0
 #3 0x0000797fd6c55510 (/lib/x86_64-linux-gnu/libc.so.6+0x3c510)
 #4 0x0000797fd6ca30fc (/lib/x86_64-linux-gnu/libc.so.6+0x8a0fc)
 #5 0x0000797fd6c55472 raise (/lib/x86_64-linux-gnu/libc.so.6+0x3c472)
 #6 0x0000797fd6c3f4b2 abort (/lib/x86_64-linux-gnu/libc.so.6+0x264b2)
 #7 0x00005802f29e35ec llvm::report_fatal_error(llvm::Twine const&, bool) (/vol/worker/clang-debian-cpp20/clang-debian-cpp20/build/bin/llc+0x345d5ec)
 #8 0x00005802f28836d8 llvm::SelectionDAGISel::CannotYetSelect(llvm::SDNode*) (/vol/worker/clang-debian-cpp20/clang-debian-cpp20/build/bin/llc+0x32fd6d8)
 #9 0x00005802f288264a llvm::SelectionDAGISel::SelectCodeCommon(llvm::SDNode*, unsigned char const*, unsigned int) (/vol/worker/clang-debian-cpp20/clang-debian-cpp20/build/bin/llc+0x32fc64a)
#10 0x00005802f02db785 (anonymous namespace)::AArch64DAGToDAGISel::Select(llvm::SDNode*) AArch64ISelDAGToDAG.cpp:0:0
#11 0x00005802f287774f llvm::SelectionDAGISel::DoInstructionSelection() (/vol/worker/clang-debian-cpp20/clang-debian-cpp20/build/bin/llc+0x32f174f)
#12 0x00005802f287676d llvm::SelectionDAGISel::CodeGenAndEmitDAG() (/vol/worker/clang-debian-cpp20/clang-debian-cpp20/build/bin/llc+0x32f076d)
#13 0x00005802f287411a llvm::SelectionDAGISel::SelectAllBasicBlocks(llvm::Function const&) (/vol/worker/clang-debian-cpp20/clang-debian-cpp20/build/bin/llc+0x32ee11a)
#14 0x00005802f28713e8 llvm::SelectionDAGISel::runOnMachineFunction(llvm::MachineFunction&) (/vol/worker/clang-debian-cpp20/clang-debian-cpp20/build/bin/llc+0x32eb3e8)
#15 0x00005802f286ed76 llvm::SelectionDAGISelLegacy::runOnMachineFunction(llvm::MachineFunction&) (/vol/worker/clang-debian-cpp20/clang-debian-cpp20/build/bin/llc+0x32e8d76)
#16 0x00005802f1c0e107 llvm::MachineFunctionPass::runOnFunction(llvm::Function&) (/vol/worker/clang-debian-cpp20/clang-debian-cpp20/build/bin/llc+0x2688107)
#17 0x00005802f214f6bc llvm::FPPassManager::runOnFunction(llvm::Function&) (/vol/worker/clang-debian-cpp20/clang-debian-cpp20/build/bin/llc+0x2bc96bc)
#18 0x00005802f2157c82 llvm::FPPassManager::runOnModule(llvm::Module&) (/vol/worker/clang-debian-cpp20/clang-debian-cpp20/build/bin/llc+0x2bd1c82)
#19 0x00005802f215021c llvm::legacy::PassManagerImpl::run(llvm::Module&) (/vol/worker/clang-debian-cpp20/clang-debian-cpp20/build/bin/llc+0x2bca21c)
#20 0x00005802effcbcd1 main (/vol/worker/clang-debian-cpp20/clang-debian-cpp20/build/bin/llc+0xa45cd1)
#21 0x0000797fd6c406ca (/lib/x86_64-linux-gnu/libc.so.6+0x276ca)
#22 0x0000797fd6c40785 __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x27785)
#23 0x00005802effc5d01 _start (/vol/worker/clang-debian-cpp20/clang-debian-cpp20/build/bin/llc+0xa3fd01)
FileCheck error: '<stdin>' is empty.
FileCheck command line:  /vol/worker/clang-debian-cpp20/clang-debian-cpp20/build/bin/FileCheck /vol/worker/clang-debian-cpp20/clang-debian-cpp20/llvm-project/llvm/test/CodeGen/AArch64/sve-i1-add-reduce.ll

--

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


```

https://github.com/llvm/llvm-project/pull/99031