<table border="1" cellspacing="0" cellpadding="8">
<tr>
<th>Issue</th>
<td>
<a href=https://github.com/llvm/llvm-project/issues/107810>107810</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>
Crash using -O3 and arm neon
</td>
</tr>
<tr>
<th>Labels</th>
<td>
new issue
</td>
</tr>
<tr>
<th>Assignees</th>
<td>
</td>
</tr>
<tr>
<th>Reporter</th>
<td>
MarkReedZ
</td>
</tr>
</table>
<pre>
I'd appreciate any tip on moving the code around to avoid this.
[bench-82d8ec.sh.txt](https://github.com/user-attachments/files/16925916/bench-82d8ec.sh.txt)
[bench-82d8ec.cpp.txt](https://github.com/user-attachments/files/16925917/bench-82d8ec.cpp.txt)
Code: https://github.com/MarkReedZ/SimSIMD/commit/09e89bb71e37b7e120a34f19012d3fc2b13183f4
Output
```
/usr/bin/clang++ -DSIMSIMD_BUILD_BENCHMARKS_WITH_CBLAS=1 -I/home/ubuntu/SimSIMD/include -I/home/ubuntu/SimSIMD/build_release/_deps/benchmark-src/include -I/home/ubuntu/SimSIMD/build_release/_deps/benchmark-build/include -O3 -std=c++17 -march=native -pedantic -ferror-limit=1 -MD -MT CMakeFiles/simsimd_bench.dir/cpp/bench.cxx.o -MF CMakeFiles/simsimd_bench.dir/cpp/bench.cxx.o.d -o CMakeFiles/simsimd_bench.dir/cpp/bench.cxx.o -c /home/ubuntu/SimSIMD/cpp/bench.cxx
In file included from /home/ubuntu/SimSIMD/cpp/bench.cxx:26:
In file included from /home/ubuntu/SimSIMD/include/simsimd/simsimd.h:111:
In file included from /home/ubuntu/SimSIMD/include/simsimd/binary.h:21:
/home/ubuntu/SimSIMD/include/simsimd/types.h:279:2: warning: #warning is a C++23 extension [-Wpedantic]
279 | #warning "Unknown compiler or architecture for bfloat16."
| ^
/home/ubuntu/SimSIMD/include/simsimd/types.h:279:2: warning: "Unknown compiler or architecture for bfloat16." [-W#warnings]
fatal error: error in backend: Cannot select: 0xc436a2f2a660: v8bf16 = fneg 0xc436a212fa20
0xc436a212fa20: v8bf16 = bitcast 0xc436a2040130
0xc436a2040130: v8i16,i64,ch = load<(load (s128) from %ir.8, align 2), <post-inc>> 0xc436a5911010, 0xc436a3a26190, Constant:i64<16>
0xc436a3a26190: i64,ch = CopyFromReg 0xc436a5911010, Register:i64 %0
0xc436a2f2ae40: i64 = Register %0
0xc436a34f11a0: i64 = Constant<16>
In function: _ZL22simsimd_dot_bf16c_neonPKtS0_yPd
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace, preprocessed source, and associated run script.
Stack dump:
0. Program arguments: /usr/bin/clang++ -DSIMSIMD_BUILD_BENCHMARKS_WITH_CBLAS=1 -I/home/ubuntu/SimSIMD/include -I/home/ubuntu/SimSIMD/build_release/_deps/benchmark-src/include -I/home/ubuntu/SimSIMD/build_release/_deps/benchmark-build/include -O3 -std=c++17 -march=native -pedantic -ferror-limit=1 -MD -MT CMakeFiles/simsimd_bench.dir/cpp/bench.cxx.o -MF CMakeFiles/simsimd_bench.dir/cpp/bench.cxx.o.d -o CMakeFiles/simsimd_bench.dir/cpp/bench.cxx.o -c /home/ubuntu/SimSIMD/cpp/bench.cxx
1. <eof> parser at end of file
2. Code generation
3. Running pass 'Function Pass Manager' on module '/home/ubuntu/SimSIMD/cpp/bench.cxx'.
4. Running pass 'AArch64 Instruction Selection' on function '@_ZL22simsimd_dot_bf16c_neonPKtS0_yPd'
Stack dump without symbol names (ensure you have llvm-symbolizer in your PATH or set the environment var `LLVM_SYMBOLIZER_PATH` to point to it):
0 libLLVM.so.18.1 0x0000e37d3259d398 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) + 84
1 libLLVM.so.18.1 0x0000e37d3259b5a8 llvm::sys::RunSignalHandlers() + 116
2 libLLVM.so.18.1 0x0000e37d324eb17c
3 libLLVM.so.18.1 0x0000e37d324eb128
4 libLLVM.so.18.1 0x0000e37d32597fcc llvm::sys::Process::Exit(int, bool) + 52
5 clang++ 0x0000c43678342560
6 libLLVM.so.18.1 0x0000e37d324f8a20 llvm::report_fatal_error(llvm::Twine const&, bool) + 248
7 libLLVM.so.18.1 0x0000e37d32d8b8b8 llvm::SelectionDAGISel::isOrEquivalentToAdd(llvm::SDNode const*) const + 0
8 libLLVM.so.18.1 0x0000e37d32d8ae08 llvm::SelectionDAGISel::SelectCodeCommon(llvm::SDNode*, unsigned char const*, unsigned int) + 13284
9 libLLVM.so.18.1 0x0000e37d341d0250
10 libLLVM.so.18.1 0x0000e37d32d83c54 llvm::SelectionDAGISel::DoInstructionSelection() + 344
11 libLLVM.so.18.1 0x0000e37d32d8343c llvm::SelectionDAGISel::CodeGenAndEmitDAG() + 900
12 libLLVM.so.18.1 0x0000e37d32d82a98 llvm::SelectionDAGISel::SelectAllBasicBlocks(llvm::Function const&) + 3980
13 libLLVM.so.18.1 0x0000e37d32d80f14 llvm::SelectionDAGISel::runOnMachineFunction(llvm::MachineFunction&) + 1496
14 libLLVM.so.18.1 0x0000e37d3295aef0 llvm::MachineFunctionPass::runOnFunction(llvm::Function&) + 680
15 libLLVM.so.18.1 0x0000e37d326f5af4 llvm::FPPassManager::runOnFunction(llvm::Function&) + 580
16 libLLVM.so.18.1 0x0000e37d326fb070 llvm::FPPassManager::runOnModule(llvm::Module&) + 64
17 libLLVM.so.18.1 0x0000e37d326f60d8 llvm::legacy::PassManagerImpl::run(llvm::Module&) + 868
18 libclang-cpp.so.18.1 0x0000e37d3a80bc64 clang::EmitBackendOutput(clang::DiagnosticsEngine&, clang::HeaderSearchOptions const&, clang::CodeGenOptions const&, clang::TargetOptions const&, clang::LangOptions const&, llvm::StringRef, llvm::Module*, clang::BackendAction, llvm::IntrusiveRefCntPtr<llvm::vfs::FileSystem>, std::unique_ptr<llvm::raw_pwrite_stream, std::default_delete<llvm::raw_pwrite_stream>>, clang::BackendConsumer*) + 2688
19 libclang-cpp.so.18.1 0x0000e37d3ab25f58 clang::BackendConsumer::HandleTranslationUnit(clang::ASTContext&) + 1180
20 libclang-cpp.so.18.1 0x0000e37d3978a5b0 clang::ParseAST(clang::Sema&, bool, bool) + 572
21 libclang-cpp.so.18.1 0x0000e37d3b53fa34 clang::FrontendAction::Execute() + 112
22 libclang-cpp.so.18.1 0x0000e37d3b4d0590 clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) + 744
23 libclang-cpp.so.18.1 0x0000e37d3b5b8e4c clang::ExecuteCompilerInvocation(clang::CompilerInstance*) + 616
24 clang++ 0x0000c436783421c4 cc1_main(llvm::ArrayRef<char const*>, char const*, void*) + 3360
25 clang++ 0x0000c4367833fbac
26 libclang-cpp.so.18.1 0x0000e37d3b1ca950
27 libLLVM.so.18.1 0x0000e37d324eb0f8 llvm::CrashRecoveryContext::RunSafely(llvm::function_ref<void ()>) + 168
28 libclang-cpp.so.18.1 0x0000e37d3b1ca1bc clang::driver::CC1Command::Execute(llvm::ArrayRef<std::optional<llvm::StringRef>>, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>*, bool*) const + 352
29 libclang-cpp.so.18.1 0x0000e37d3b198d3c clang::driver::Compilation::ExecuteCommand(clang::driver::Command const&, clang::driver::Command const*&, bool) const + 756
30 libclang-cpp.so.18.1 0x0000e37d3b198f4c clang::driver::Compilation::ExecuteJobs(clang::driver::JobList const&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*>>&, bool) const + 136
31 libclang-cpp.so.18.1 0x0000e37d3b1b12f4 clang::driver::Driver::ExecuteCompilation(clang::driver::Compilation&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*>>&) + 324
32 clang++ 0x0000c4367833f344 clang_main(int, char**, llvm::ToolContext const&) + 9756
33 clang++ 0x0000c4367834ae40 main + 92
34 libc.so.6 0x0000e37d3caa84c4
35 libc.so.6 0x0000e37d3caa8598 __libc_start_main + 152
36 clang++ 0x0000c4367833c970 _start + 48
clang++: error: clang frontend command failed with exit code 70 (use -v to see invocation)
Ubuntu clang version 18.1.3 (1ubuntu1)
Target: aarch64-unknown-linux-gnu
Thread model: posix
InstalledDir: /usr/bin
clang++: note: diagnostic msg:
********************
```
To repro on an AWS c7g
```
sudo apt-get update && sudo apt-get install cmake build-essential libjemalloc-dev g++-13 gcc-13 clang libopenblas-dev -y
git clone https://github.com/MarkReedZ/SimSIMD.git
cd SimSIMD/
git fetch && git checkout dot_bf16c_neon
cmake -D CMAKE_BUILD_TYPE=Release -D SIMSIMD_BUILD_TESTS=1 -D SIMSIMD_BUILD_BENCHMARKS=1 -D SIMSIMD_BUILD_BENCHMARKS_WITH_CBLAS=1 -DCMAKE_VERBOSE_MAKEFILE:BOOL=ON -D CMAKE_C_COMPILER="/usr/bin/clang" -D CMAKE_CXX_COMPILER="/usr/bin/clang++" -B build_release
cmake --build build_release
```
</pre>
<img width="1px" height="1px" alt="" src="http://email.email.llvm.org/o/eJzsWl9zqziy_zTkRWUXkgDDQx4c_5mTnWSSijMzu_PiEkLY2oDESsInvp_-lgTY4Dixz9y5-zSnTjlYtPqfun_dkky05hvB2K0X3nnh_IbUZivV7SNRby-MZX_cpDLb3957aJIBUlWKUU4MA0TsgeEVkAKUcsfFBpgtA1RmDBAla5EBIwHZSZ4Bs-V67Plzz5-2n-FdygTdjmKUxYyO9XZs3o0Xzj0Ub42ptIenHlp6aLnhZlunYypLDy1rzdSIGEPotmTCaA8tc14w-xdGCQoTGHloeY4zSs4LplX1F0menEruWB9Eu8-ZzJiHp-ALWQfHe2i54uXq_nHuoSWVZcmNh5Z-wuIkTSeQ4Uk6YRD5BAc5THyIMpxTlEIMY5wHfalPtalq045Efvu_-WqNU1Z5LqyYgoiNh-48dAdG89X9oxW_vvv1_mG-vlv8Mvv2OH35ebX-_f7123p29zBdeXgOwejeQ8utLJnlltbC1APduaBFnbFLZGnNi2ytWMGItiTrjFW6c2tJ1NtIK_pXsnMUfYZPGIy0yTw8p40P4ASMSqLo1sNzQQzfMTCqWEaE4RSMcqaUVKOC25Vxfnicg9HjK5g9kje2bANE81LzMls7ueOMW2fTquo0GdP397EEo8fln5g2zsBI_ilxFHzpvJMZTazcC2CjHrT-ykCuZPljfPAURTbs_yy_lvRo5_FpvPXwFEL4V7NPuSBq77ijI_MfZmP2FdMNl0liPy0MfCdKcLGxjx7C7TfANSBg1kQgwoC9GyY0lwJ44d3o9y7-LGg5VQBAkwR4k1mfh4fQr-JNyO8CUFlWvGAKSAVsLHPDqKkVA7lUIM0LSQyMxh5CHTv7z7ELF_9vxv64do31RxP1wQE5MaQALhktc_cAuAApoW9MZHZsRoSQBmhWMGrsgP9OAxwRlCMSRb4d2cVpDiPg4TnIBdscKCDKCWrR8nRwOC3lhhJtDkR-4EPsH716Mu4mc1uzZjwKPDSjW8emkCTz8MxDsX0CHoo1RLGHki6AQ67GsYdmgBR8IwCyNQbNgIdnldRmxAX18MLDi05gmEDoQ9_StCOYoAgmbmQmhTZEWKdYLfAMRnZ2LxRO5uApGKg7k9V-qWT5cvRZT-AL23BtmGrYW-VPXZkjwoKOrePYzelTDzQJcgjJYMrRir7-FgFqQQ2XwhKv_3hAqMPHTJq1XTm6FkyK55_Nyl_vn7Nm4vPDYrpaAF2nJTeAgLTeAMUqqYztar4o3kWx6_6MKiX_baMNLbnWtQNnQETW4VHTLymity5QjSKUWY9VilVKUqY1y4CWtWqG7UyitXTdVwZULYCmilem7axWhtA3kNVldcAof-z5ybOSG0VKQNSmbnoXl39_V_2_q_51VR_aKPLwjMncYkpFlGYKEAOYyIDMXY1tKJGltB0u2DDBFHF5595g--alFq40VURr4KHJsk1N8GwHHokgG6Y8NGm2FFldMEv1QwqjSZsNwTmB06mi2ygA90IbVTeyV64iWEUbwR1eONGBfxVkoMlpCoLv3GxlbYDel6ksgCAlsyrETGhb2_ayBluyY8ABRUPE_4e5qrWXtQLP09dvtiJqZhxOMLHjSgqbwGBHFPAi_-Hht8f16l-Pd08P938sXtZ2ihf5FqAqyYVDKu72Hwc8AKDgqZ031nIM4zEE_rvv-z7DkwyjMMlwEjuV7BQ81XvdPDwrLoyz7rVBqfhIpMj3tdRGMVJ6yNYywIWVCiyYxO02BH6U3AJ6X3wakrPiX2qx4htBim9EZAVT2mvKoZUAYdQG39fGBSyFE9pG4xXaWHoUt8F0jfKTnNLzvnNY3nxZvNsViZ2HZiCVsujsCNvuKwSgj8aDf41AWwInMQ5Q2O3hogum5zFBfk-3ppKtXdu0btqm_oq-fufC7uSFNu2K9hVFQeuVyRVezOI0Tvtreki3-fSn-xUrmlGun9TiPzXfkYIJ8yqnWTbQaDX_xaJKq9LUquKenUKtE-Kr1CHMv6xOM2qBbCbL0kLDB12cFjNQC3d2kgG6JaqnX-9NLxsgRl1CJJe1DWDmH_of6F9jHaZhcNG6uezhXw_-DimFgy5r4ZdxlcU4wPSiPOvHn5iYimxRcjOf_tQTlfidfega-xBJrl29aVHcEc3pXSHpmx6s4KHuHEO8NTyJO3XwNer4ObzsblWLJ_FI6JYL1kkeqPPh3UEfGCQtuMErICgJCcv7aX7C2FbZnkpndTmjRHTwSXhZhygPSd73yfLZiu1q-49LDw_So2ukp_7Ev0L6o-suhqvQDh3t7pJg8mUSRHnkZ_2gLNiG0H2L_Ufp92V1DIivJcdRi7AwtqJdORjRqjonn8R-SqOgrRlNjSm5uWt2vu25H4p7r-ecbITUhlO9EBsuWIvxPZJvjGRMrZhtgZ8quyJ6UA56pG1yX6B6JWrDzAWiByI250h6CWYUF5sXlg-HOwdOTxi2Tpi2MdWfci-MqjXfsReWz4R5NsrDs-PrXd5mim2vV3ttWGn3lGgG3D7BvqkF_0_N1tXJTNsNVd8VN2zd9US9SRnLSV2YdcYKZtiFiW4Lf94ku9utS9ssTw9lOYq7qEkuR02KwjyMv-LcBILrt14VEbpw3fyvgp-E03T1OpPCsPc-kELYpS3yLyqTTGISpn5fmWe7x5iuXoeiVqwkg4bkpIOatC0UghdlpiHOCR6kzVJZMw7h0rZrjNaGDdrNTgi6LCTI_DDxh-nSHHbdu9MKygZiukCNP9fq6OJJV6QRvsLaNGYBHYBEI_Koz05S8lH8B32PARcdGu_g6o4V0gBQCtcl4UMMnCpF9jax8WzYSbUZcNpd7STPerpg3LXCKBwoM5CP85S0OwAUXXYapCTp2i_0sQic2zH4eb8SzBTR2xdG5Y6pfZckhw0NyVmxHzih23qulXOEuzprQs-5oQ3Arjigy8XBmgDTwbpniu-67J7NoO1vichOo_3swhxQTDqQJsUAv47YfMCtw4T1mr6_NwfzeJrarsxinDsKdss9ILYDa6MIN7p7fcKOFIUNVql67y3J9IgIJ1sE3O2u0GVsTGESZ_hzp7mMIB8wovPkIH1OJlqCz6rfF6TTk13Y0a5J2OYgvgyz1q48-GG7_iFT_blR_5DpA9fms3pdkqL4jVEj2_bnGEMV4Xb52o3wtX5oF_oTb0DceeOKAgBTiPLgM8nz3vMAKs9g5Gde_C96o0VB1JYEjK5EZJzjoPVBh8mdDi4tp21S9c4GpCxaKPuwfUqO4Yg_R-GAsMAHVlozqc1M7HY41K5V1F8oSkgc0M6wsEf0wagDfZjEYL22lGttiDLrgzTYAQGOrnURTSY-aPg4Ft3xR2_64dLJPrhxkLd1G9B21XLCC5a5c0HA3rlpfikx8S3C15qB0Q4YCTRjgPdqcfvbgV_dyWfLeseUuwy0IT3Gdj5sTkbhgb7pt602hLgjz1Hd3LaNCi7q99FG1C3hVjGSgVJmbrsKKqn54bJXG1IULJtz9eHK4JwHhDTupw3ZYYMBSt3c9rWXiP-H_2d_uvDh81UCd3kCpABEgOnvK0Anm7OT7ULrOpOAVGa0YQbUVUYMAy6eo-Er3rgC0JK8MeDuD0ZMayYMJ4WNyH-z0hWlUcZ2oHXJCGKwodT-adat4KmsmEgLoh3daN9qsrHRUEjBfvBXIeMNN0djaAaO5-I9zjkzdNuZ5URtGX2TtQHD4-y-Hx0_Z-xoDmaP058X7WXQ67-eFx6evzTXK_bt8LLodbF6bS-HTl8d75Euvf9wzzRvVPht8XL3tFqs7Zfl_cPC7lqenh48PH_65ajobD17eny-f1i8eHjuIXT-qgv1Jvzzn1dNcXFuJ96B4SXTqcuaG6ZzRIcYvMlucZbghNywWzhBYRz5EQ5vtrd5HOapH0KCcDSBGQ5pGECWkJQFaRQTdMNvkY8CP_ETPwxwGI7j2I9gwijCIclJzrzAZyXhxdiC9liqzY27fbyF_iSG_k1BUlZo91svhAT7Dtxba3Q4v1G37j4irTfaC_yCa6OPbAw3Bbt1TS2oNRcbd3PmriVVCWwI3dSquP3zl6Othrtb9L8BAAD__7idkhI">