[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-x86_64-debian-fast` 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/56/builds/2978

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: /b/1/clang-x86_64-debian-fast/llvm.obj/bin/llc -mtriple=aarch64-linux-gnu -mattr=+sve < /b/1/clang-x86_64-debian-fast/llvm.src/llvm/test/CodeGen/AArch64/sve-i1-add-reduce.ll | /b/1/clang-x86_64-debian-fast/llvm.obj/bin/FileCheck /b/1/clang-x86_64-debian-fast/llvm.src/llvm/test/CodeGen/AArch64/sve-i1-add-reduce.ll
+ /b/1/clang-x86_64-debian-fast/llvm.obj/bin/llc -mtriple=aarch64-linux-gnu -mattr=+sve
+ /b/1/clang-x86_64-debian-fast/llvm.obj/bin/FileCheck /b/1/clang-x86_64-debian-fast/llvm.src/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: /b/1/clang-x86_64-debian-fast/llvm.obj/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 0x00000000034e28b7 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/b/1/clang-x86_64-debian-fast/llvm.obj/bin/llc+0x34e28b7)
 #1 0x00000000034e037e llvm::sys::RunSignalHandlers() (/b/1/clang-x86_64-debian-fast/llvm.obj/bin/llc+0x34e037e)
 #2 0x00000000034e2f8f SignalHandler(int) Signals.cpp:0:0
 #3 0x00007fa5e7cbc140 __restore_rt (/lib/x86_64-linux-gnu/libpthread.so.0+0x13140)
 #4 0x00007fa5e77d0ce1 raise (/lib/x86_64-linux-gnu/libc.so.6+0x38ce1)
 #5 0x00007fa5e77ba537 abort (/lib/x86_64-linux-gnu/libc.so.6+0x22537)
 #6 0x000000000345555a llvm::report_fatal_error(llvm::Twine const&, bool) (/b/1/clang-x86_64-debian-fast/llvm.obj/bin/llc+0x345555a)
 #7 0x00000000032dca8f llvm::SelectionDAGISel::CannotYetSelect(llvm::SDNode*) (/b/1/clang-x86_64-debian-fast/llvm.obj/bin/llc+0x32dca8f)
 #8 0x00000000032dbc6c llvm::SelectionDAGISel::SelectCodeCommon(llvm::SDNode*, unsigned char const*, unsigned int) (/b/1/clang-x86_64-debian-fast/llvm.obj/bin/llc+0x32dbc6c)
 #9 0x0000000000b5b8fd (anonymous namespace)::AArch64DAGToDAGISel::Select(llvm::SDNode*) AArch64ISelDAGToDAG.cpp:0:0
#10 0x00000000032cffff llvm::SelectionDAGISel::DoInstructionSelection() (/b/1/clang-x86_64-debian-fast/llvm.obj/bin/llc+0x32cffff)
#11 0x00000000032cef8c llvm::SelectionDAGISel::CodeGenAndEmitDAG() (/b/1/clang-x86_64-debian-fast/llvm.obj/bin/llc+0x32cef8c)
#12 0x00000000032cca4b llvm::SelectionDAGISel::SelectAllBasicBlocks(llvm::Function const&) (/b/1/clang-x86_64-debian-fast/llvm.obj/bin/llc+0x32cca4b)
#13 0x00000000032c9d60 llvm::SelectionDAGISel::runOnMachineFunction(llvm::MachineFunction&) (/b/1/clang-x86_64-debian-fast/llvm.obj/bin/llc+0x32c9d60)
#14 0x00000000032c7526 llvm::SelectionDAGISelLegacy::runOnMachineFunction(llvm::MachineFunction&) (/b/1/clang-x86_64-debian-fast/llvm.obj/bin/llc+0x32c7526)
#15 0x0000000002633370 llvm::MachineFunctionPass::runOnFunction(llvm::Function&) (/b/1/clang-x86_64-debian-fast/llvm.obj/bin/llc+0x2633370)
#16 0x0000000002b66fa0 llvm::FPPassManager::runOnFunction(llvm::Function&) (/b/1/clang-x86_64-debian-fast/llvm.obj/bin/llc+0x2b66fa0)
#17 0x0000000002b6da01 llvm::FPPassManager::runOnModule(llvm::Module&) (/b/1/clang-x86_64-debian-fast/llvm.obj/bin/llc+0x2b6da01)
#18 0x0000000002b67651 llvm::legacy::PassManagerImpl::run(llvm::Module&) (/b/1/clang-x86_64-debian-fast/llvm.obj/bin/llc+0x2b67651)
#19 0x0000000000829d81 compileModule(char**, llvm::LLVMContext&) llc.cpp:0:0
#20 0x000000000082735d main (/b/1/clang-x86_64-debian-fast/llvm.obj/bin/llc+0x82735d)
#21 0x00007fa5e77bbd0a __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x23d0a)
#22 0x000000000082618a _start (/b/1/clang-x86_64-debian-fast/llvm.obj/bin/llc+0x82618a)
FileCheck error: '<stdin>' is empty.
FileCheck command line:  /b/1/clang-x86_64-debian-fast/llvm.obj/bin/FileCheck /b/1/clang-x86_64-debian-fast/llvm.src/llvm/test/CodeGen/AArch64/sve-i1-add-reduce.ll

--

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


```

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