LLVM/clang OpenMP - anyone?

Tái hiện ví dụ OpenMP tối thiểu bằng lệnh clang++ wasm32-wasi được nêu. Bắt đầu tại llvm/lib/MC/MCWasmStreamer.cpp:164 và đường dẫn lời gọi WebAssemblyAsmPrinter.cpp:177 trong stack trace. Được xem là hoàn tất khi ví dụ không còn abort trong backend và hỗ trợ OpenMP cần thiết đã được xác định rõ ràng.

Hi,

has anyone thought about it yet? So far - not even thinking of compiling libomp to wasm - even a minimal example fails in the backend, e.g.:

#pragma optimize off
#include <stddef.h>
#include <stdint.h>
#include <stdlib.h>
#include "anet_intrinsic.h"
//#include <omp.h>

int main() {
    #pragma omp parallel num_threads(4)
    {
        #pragma omp critical
        abs(-5555);
    }
}

>>>
C:\LLVM\BUILDLLDB\Debug\bin\clang++ -fopenmp -DDEBUG -mbulk-memory -mmutable-globals -O0 -I.. -I..\.. -I. -Wl,--max-memory=327680 -Wl,--shared-memory -matomics -target wasm32-wasi --sysroot /project/wasi-libc/sysroot-intrin-bulk-memory -Wl,--export-all  -Wl,-L.  -Wl,--entry=__main_void -Wl,--allow-undefined -o omp_dummy.cc.wasm omp_dummy.cc
Common symbols are not yet implemented for Wasm
UNREACHABLE executed at C:\LLVM\llvm\lib\MC\MCWasmStreamer.cpp:164!
PLEASE submit a bug report to https://bugs.llvm.org/ and include the crash backtrace, preprocessed source, and associated run script.
Stack dump:
0.      Program arguments: C:\\LLVM\\BUILDLLDB\\Debug\\bin\\clang++.exe -cc1 -triple wasm32-unknown-wasi -emit-obj -mrelax-all --mrelax-relocations -disable-free -clear-ast-before-backend -main-file-name omp_dummy.cc -mrelocation-model static -mframe-pointer=none -ffp-contract=on -fno-rounding-math -mconstructor-aliases -target-cpu generic -target-feature +bulk-memory -target-feature +mutable-globals -target-feature +atomics -fvisibility hidden -debugger-tuning=gdb -fcoverage-compilation-dir=C:\\project\\ALP\\WASM\\exc\\exc_newproposal -resource-dir C:\\LLVM\\BUILDLLDB\\Debug\\lib\\clang\\14.0.0 -D DEBUG -I .. -I ..\\.. -I . -isysroot /project/wasi-libc/sysroot-intrin-bulk-memory -internal-isystem /project/wasi-libc/sysroot-intrin-bulk-memory/include/wasm32-wasi/c++/v1 -internal-isystem /project/wasi-libc/sysroot-intrin-bulk-memory/include/c++/v1 -internal-isystem C:\\LLVM\\BUILDLLDB\\Debug\\lib\\clang\\14.0.0\\include -internal-isystem /project/wasi-libc/sysroot-intrin-bulk-memory/include/wasm32-wasi -internal-isystem /project/wasi-libc/sysroot-intrin-bulk-memory/include -O0 -fdeprecated-macro -fdebug-compilation-dir=C:\\project\\ALP\\WASM\\exc\\exc_newproposal -ferror-limit 19 -fmessage-length=120 -fopenmp -fgnuc-version=4.2.1 -fcxx-exceptions -fexceptions -fcolor-diagnostics -o C:\\Users\\I\\AppData\\Local\\Temp\\omp_dummy-17eebb.o -x c++ omp_dummy.cc
1.      <eof> parser at end of file
2.      Code generation
 #0 0x00007ff7b0397c2c HandleAbort C:\LLVM\llvm\lib\Support\Windows\Signals.inc:408:0
 #1 0x00007ffc24a18e05 (C:\Windows\SYSTEM32\ucrtbased.dll+0xa8e05)
 #2 0x00007ffc24a1ab29 (C:\Windows\SYSTEM32\ucrtbased.dll+0xaab29)
 #3 0x00007ff7b036d21f llvm::llvm_unreachable_internal(char const *, char const *, unsigned int) C:\LLVM\llvm\lib\Support\ErrorHandling.cpp:215:0
 #4 0x00007ff7afca1ed2 llvm::MCWasmStreamer::emitCommonSymbol(class llvm::MCSymbol *, unsigned __int64, unsigned int) C:\LLVM\llvm\lib\MC\MCWasmStreamer.cpp:165:0
 #5 0x00007ff7b207ad3c llvm::AsmPrinter::emitGlobalVariable(class llvm::GlobalVariable const *) C:\LLVM\llvm\lib\CodeGen\AsmPrinter\AsmPrinter.cpp:580:0
 #6 0x00007ff7ada22e9e llvm::WebAssemblyAsmPrinter::emitGlobalVariable(class llvm::GlobalVariable const *) C:\LLVM\llvm\lib\Target\WebAssembly\WebAssemblyAsmPrinter.cpp:177:0
 #7 0x00007ff7b20745b7 llvm::AsmPrinter::doFinalization(class llvm::Module &) C:\LLVM\llvm\lib\CodeGen\AsmPrinter\AsmPrinter.cpp:1737:0
 #8 0x00007ff7af174176 llvm::FPPassManager::doFinalization(class llvm::Module &) C:\LLVM\llvm\lib\IR\LegacyPassManager.cpp:1503:0
 #9 0x00007ff7af175852 `anonymous namespace'::MPPassManager::runOnModule C:\LLVM\llvm\lib\IR\LegacyPassManager.cpp:1590:0
#10 0x00007ff7af176375 llvm::legacy::PassManagerImpl::run(class llvm::Module &) C:\LLVM\llvm\lib\IR\LegacyPassManager.cpp:542:0
#11 0x00007ff7af16e292 llvm::legacy::PassManager::run(class llvm::Module &) C:\LLVM\llvm\lib\IR\LegacyPassManager.cpp:1682:0
#12 0x00007ff7b0cf0d01 `anonymous namespace'::EmitAssemblyHelper::RunCodegenPipeline C:\LLVM\clang\lib\CodeGen\BackendUtil.cpp:1520:0
#13 0x00007ff7b0cf1f38 `anonymous namespace'::EmitAssemblyHelper::EmitAssembly C:\LLVM\clang\lib\CodeGen\BackendUtil.cpp:1550:0
#14 0x00007ff7b0cece03 clang::EmitBackendOutput(class clang::DiagnosticsEngine &, class clang::HeaderSearchOptions const &, class clang::CodeGenOptions const &, class clang::TargetOptions const &, class clang::LangOptions const &, class llvm::StringRef, class llvm::Module *, enum clang::BackendAction, class std::unique_ptr<class llvm::raw_pwrite_stream, struct std::default_delete<class llvm::raw_pwrite_stream>>) C:\LLVM\clang\lib\CodeGen\BackendUtil.cpp:1714:0
#15 0x00007ff7b7aeead1 clang::BackendConsumer::HandleTranslationUnit(class clang::ASTContext &) C:\LLVM\clang\lib\CodeGen\CodeGenAction.cpp:374:0
#16 0x00007ff7b4b5f538 clang::ParseAST(class clang::Sema &, bool, bool) C:\LLVM\clang\lib\Parse\ParseAST.cpp:178:0
#17 0x00007ff7b1976a07 clang::ASTFrontendAction::ExecuteAction(void) C:\LLVM\clang\lib\Frontend\FrontendAction.cpp:1076:0
#18 0x00007ff7b7ae24e7 clang::CodeGenAction::ExecuteAction(void) C:\LLVM\clang\lib\CodeGen\CodeGenAction.cpp:1108:0
#19 0x00007ff7b19763be clang::FrontendAction::Execute(void) C:\LLVM\clang\lib\Frontend\FrontendAction.cpp:971:0
#20 0x00007ff7b18f5106 clang::CompilerInstance::ExecuteAction(class clang::FrontendAction &) C:\LLVM\clang\lib\Frontend\CompilerInstance.cpp:1030:0
#21 0x00007ff7b1b62648 clang::ExecuteCompilerInvocation(class clang::CompilerInstance *) C:\LLVM\clang\lib\FrontendTool\ExecuteCompilerInvocation.cpp:261:0
#22 0x00007ff7ab8becf4 cc1_main(class llvm::ArrayRef<char const *>, char const *, void *) C:\LLVM\clang\tools\driver\cc1_main.cpp:246:0
#23 0x00007ff7ab8aa410 ExecuteCC1Tool C:\LLVM\clang\tools\driver\driver.cpp:317:0

Can anyone oversee what must be implemented to achieve this?

Thanks,
S.