[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 `llvm-clang-x86_64-gcc-ubuntu` running on `sie-linux-worker3` while building `llvm` at step 6 "test-build-unified-tree-check-all".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/174/builds/2075

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: /home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/build/bin/llc -mtriple=aarch64-linux-gnu -mattr=+sve < /home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/test/CodeGen/AArch64/sve-i1-add-reduce.ll | /home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/build/bin/FileCheck /home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/test/CodeGen/AArch64/sve-i1-add-reduce.ll
+ /home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/build/bin/FileCheck /home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/test/CodeGen/AArch64/sve-i1-add-reduce.ll
+ /home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/build/bin/llc -mtriple=aarch64-linux-gnu -mattr=+sve
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: /home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/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 0x000055f76c50d97f llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/build/bin/llc+0x3dfe97f)
 #1 0x000055f76c50aec4 SignalHandler(int) Signals.cpp:0:0
 #2 0x00007f0cd568f420 __restore_rt (/lib/x86_64-linux-gnu/libpthread.so.0+0x14420)
 #3 0x00007f0cd515c00b raise /build/glibc-LcI20x/glibc-2.31/signal/../sysdeps/unix/sysv/linux/raise.c:51:1
 #4 0x00007f0cd513b859 abort /build/glibc-LcI20x/glibc-2.31/stdlib/abort.c:81:7
 #5 0x000055f7690ea55e llvm::SuffixTree::insertInternalNode(llvm::SuffixTreeInternalNode*, unsigned int, unsigned int, unsigned int) (.cold) SuffixTree.cpp:0:0
 #6 0x000055f76c2aa60b llvm::SelectionDAGISel::CannotYetSelect(llvm::SDNode*) (/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/build/bin/llc+0x3b9b60b)
 #7 0x000055f76c2b07ba llvm::SelectionDAGISel::SelectCodeCommon(llvm::SDNode*, unsigned char const*, unsigned int) (/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/build/bin/llc+0x3ba17ba)
 #8 0x000055f7695b1c2a (anonymous namespace)::AArch64DAGToDAGISel::Select(llvm::SDNode*) AArch64ISelDAGToDAG.cpp:0:0
 #9 0x000055f76c2a729c llvm::SelectionDAGISel::DoInstructionSelection() (/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/build/bin/llc+0x3b9829c)
#10 0x000055f76c2b62c4 llvm::SelectionDAGISel::CodeGenAndEmitDAG() (/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/build/bin/llc+0x3ba72c4)
#11 0x000055f76c2b935d llvm::SelectionDAGISel::SelectAllBasicBlocks(llvm::Function const&) (/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/build/bin/llc+0x3baa35d)
#12 0x000055f76c2ba83f llvm::SelectionDAGISel::runOnMachineFunction(llvm::MachineFunction&) (/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/build/bin/llc+0x3bab83f)
#13 0x000055f76c2abac3 llvm::SelectionDAGISelLegacy::runOnMachineFunction(llvm::MachineFunction&) (/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/build/bin/llc+0x3b9cac3)
#14 0x000055f76b45dcd5 llvm::MachineFunctionPass::runOnFunction(llvm::Function&) (.part.0) MachineFunctionPass.cpp:0:0
#15 0x000055f76ba6725b llvm::FPPassManager::runOnFunction(llvm::Function&) (/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/build/bin/llc+0x335825b)
#16 0x000055f76ba674a9 llvm::FPPassManager::runOnModule(llvm::Module&) (/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/build/bin/llc+0x33584a9)
#17 0x000055f76ba67d55 llvm::legacy::PassManagerImpl::run(llvm::Module&) (/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/build/bin/llc+0x3358d55)
#18 0x000055f7691f2fb9 compileModule(char**, llvm::LLVMContext&) llc.cpp:0:0
#19 0x000055f7690f1f16 main (/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/build/bin/llc+0x9e2f16)
#20 0x00007f0cd513d083 __libc_start_main /build/glibc-LcI20x/glibc-2.31/csu/../csu/libc-start.c:342:3
#21 0x000055f7691e96be _start (/home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/build/bin/llc+0xada6be)
FileCheck error: '<stdin>' is empty.
FileCheck command line:  /home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/build/bin/FileCheck /home/buildbot/buildbot-root/llvm-clang-x86_64-gcc-ubuntu/llvm-project/llvm/test/CodeGen/AArch64/sve-i1-add-reduce.ll

--

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


```

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