[flang][openmp][mlir] - flang-new crashes when omp.task and omp.target are used in the same function

[bhandarkar-pranav]

Command

flang-new   -O2    -fopenmp --offload-arch=gfx90a  -D__OFFLOAD_ARCH_gfx90a__ f.f95 -o f.out

Crash signature

PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace.
Stack dump:
0.      Program arguments: /work/prbhanda/git/bhandarkar-pranav/build/install_18.0-0-25_Jan_24_23_23/bin/flang-new -fc1 -triple amdgcn\
-amd-amdhsa -emit-llvm-bc -D __OFFLOAD_ARCH_gfx90a__ -fopenmp -mrelocation-model pic -pic-level 2 -target-cpu gfx90a -fopenmp-host-ir-\
file-path /tmp/f-6566c4.bc -fopenmp-is-target-device -mframe-pointer=none -O2 -o /tmp/f-gfx90a-e38eba.bc -x f95-cpp-input f.f95
 #0 0x00007f98c95dcac0 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/work/prbhanda/git/bhandarkar-pranav/build/install_18.0-0-\
25_Jan_24_23_23/bin/../lib/libLLVMSupport.so.19.0git+0x1dcac0)
 #1 0x00007f98c95d9ecf llvm::sys::RunSignalHandlers() (/work/prbhanda/git/bhandarkar-pranav/build/install_18.0-0-25_Jan_24_23_23/bin/.\
./lib/libLLVMSupport.so.19.0git+0x1d9ecf)
 #2 0x00007f98c95da025 SignalHandler(int) Signals.cpp:0:0
 #3 0x00007f98c8c42520 (/lib/x86_64-linux-gnu/libc.so.6+0x42520)
 #4 0x00007f98c70cee2c llvm::CodeExtractorAnalysisCache::CodeExtractorAnalysisCache(llvm::Function&) (/work/prbhanda/git/bhandarkar-pr\
anav/build/install_18.0-0-25_Jan_24_23_23/bin/../lib/../lib/libLLVMTransformUtils.so.19.0git+0xcee2c)
 #5 0x00007f98c2d4cbc5 llvm::OpenMPIRBuilder::finalize(llvm::Function*) (/work/prbhanda/git/bhandarkar-pranav/build/install_18.0-0-25_\
Jan_24_23_23/bin/../lib/../lib/libLLVMFrontendOpenMP.so.19.0git+0x6ebc5)
 #6 0x00007f98ca3b2c31 mlir::LLVM::ModuleTranslation::~ModuleTranslation() (/work/prbhanda/git/bhandarkar-pranav/build/install_18.0-0-\
25_Jan_24_23_23/bin/../lib/../lib/libMLIRTargetLLVMIRExport.so.19.0git+0x24c31)
 #7 0x00007f98ca3c9c13 mlir::translateModuleToLLVMIR(mlir::Operation*, llvm::LLVMContext&, llvm::StringRef) (/work/prbhanda/git/bhanda\
rkar-pranav/build/install_18.0-0-25_Jan_24_23_23/bin/../lib/../lib/libMLIRTargetLLVMIRExport.so.19.0git+0x3bc13)
 #8 0x00007f98cbdc8fef Fortran::frontend::CodeGenAction::generateLLVMIR() (/work/prbhanda/git/bhandarkar-pranav/build/install_18.0-0-2\
5_Jan_24_23_23/bin/../lib/libflangFrontend.so.19.0git+0x148fef)
 #9 0x00007f98cbdcbba0 Fortran::frontend::CodeGenAction::executeAction() (/work/prbhanda/git/bhandarkar-pranav/build/install_18.0-0-25\
_Jan_24_23_23/bin/../lib/libflangFrontend.so.19.0git+0x14bba0)
#10 0x00007f98cbcdb091 Fortran::frontend::FrontendAction::execute() (/work/prbhanda/git/bhandarkar-pranav/build/install_18.0-0-25_Jan_\
24_23_23/bin/../lib/libflangFrontend.so.19.0git+0x5b091)
#11 0x00007f98cbccb2e3 Fortran::frontend::CompilerInstance::executeAction(Fortran::frontend::FrontendAction&) (/work/prbhanda/git/bhan\
darkar-pranav/build/install_18.0-0-25_Jan_24_23_23/bin/../lib/libflangFrontend.so.19.0git+0x4b2e3)
#12 0x00007f98cc5a6b1b Fortran::frontend::executeCompilerInvocation(Fortran::frontend::CompilerInstance*) (/work/prbhanda/git/bhandark\
ar-pranav/build/install_18.0-0-25_Jan_24_23_23/bin/../lib/libflangFrontendTool.so.19.0git+0x4b1b)
#13 0x000055cd42a84c38 fc1_main(llvm::ArrayRef<char const*>, char const*) (/work/prbhanda/git/bhandarkar-pranav/build/install_18.0-0-2\
5_Jan_24_23_23/bin/flang-new+0x5c38)
#14 0x000055cd42a8335d main (/work/prbhanda/git/bhandarkar-pranav/build/install_18.0-0-25_Jan_24_23_23/bin/flang-new+0x435d)
#15 0x00007f98c8c29d90 __libc_start_call_main ./csu/../sysdeps/nptl/libc_start_call_main.h:58:16
#16 0x00007f98c8c29e40 call_init ./csu/../csu/libc-start.c:128:20
#17 0x00007f98c8c29e40 __libc_start_main ./csu/../csu/libc-start.c:379:5
#18 0x000055cd42a83865 _start (/work/prbhanda/git/bhandarkar-pranav/build/install_18.0-0-25_Jan_24_23_23/bin/flang-new+0x4865)
flang-new: error: unable to execute command: Segmentation fault (core dumped)
flang-new: error: flang frontend command failed due to signal (use -v to see invocation)
flang-new version 19.0.0git ([email protected]:bhandarkar-pranav/llvm-project.git 2e0ddfc1638597e0d08fb028fdd6754387732107)
Target: x86_64-unknown-linux-gnu
Thread model: posix

cat f.f95
program main
      implicit none
      integer :: N = 5
      integer, dimension(5) :: a
      integer, dimension(5) :: b
      integer :: i
      integer :: target_a = 0
      !$omp task depend(out:a)
      do i = 1, N
         a(i) = i
      end do
      !$omp end task


      !$omp target map(tofrom:target_a) map(tofrom:a)
      do i = 1, N
         target_a = target_a + i
         a(i) = a(i) + i
      end do
      !$omp end target
      print*, target_a
      print*, a
end program main

[llvmbot]

@llvm/issue-subscribers-flang-ir

Author: Pranav Bhandarkar (bhandarkar-pranav)

Command ``` flang-new -O2 -fopenmp --offload-arch=gfx90a -D__OFFLOAD_ARCH_gfx90a__ f.f95 -o f.out ``` Crash signature ``` PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace. Stack dump: 0. Program arguments: /work/prbhanda/git/bhandarkar-pranav/build/install_18.0-0-25_Jan_24_23_23/bin/flang-new -fc1 -triple amdgcn\ -amd-amdhsa -emit-llvm-bc -D __OFFLOAD_ARCH_gfx90a__ -fopenmp -mrelocation-model pic -pic-level 2 -target-cpu gfx90a -fopenmp-host-ir-\ file-path /tmp/f-6566c4.bc -fopenmp-is-target-device -mframe-pointer=none -O2 -o /tmp/f-gfx90a-e38eba.bc -x f95-cpp-input f.f95 #0 0x00007f98c95dcac0 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/work/prbhanda/git/bhandarkar-pranav/build/install_18.0-0-\ 25_Jan_24_23_23/bin/../lib/libLLVMSupport.so.19.0git+0x1dcac0) #1 0x00007f98c95d9ecf llvm::sys::RunSignalHandlers() (/work/prbhanda/git/bhandarkar-pranav/build/install_18.0-0-25_Jan_24_23_23/bin/.\ ./lib/libLLVMSupport.so.19.0git+0x1d9ecf) #2 0x00007f98c95da025 SignalHandler(int) Signals.cpp:0:0 #3 0x00007f98c8c42520 (/lib/x86_64-linux-gnu/libc.so.6+0x42520) #4 0x00007f98c70cee2c llvm::CodeExtractorAnalysisCache::CodeExtractorAnalysisCache(llvm::Function&) (/work/prbhanda/git/bhandarkar-pr\ anav/build/install_18.0-0-25_Jan_24_23_23/bin/../lib/../lib/libLLVMTransformUtils.so.19.0git+0xcee2c) #5 0x00007f98c2d4cbc5 llvm::OpenMPIRBuilder::finalize(llvm::Function*) (/work/prbhanda/git/bhandarkar-pranav/build/install_18.0-0-25_\ Jan_24_23_23/bin/../lib/../lib/libLLVMFrontendOpenMP.so.19.0git+0x6ebc5) #6 0x00007f98ca3b2c31 mlir::LLVM::ModuleTranslation::~ModuleTranslation() (/work/prbhanda/git/bhandarkar-pranav/build/install_18.0-0-\ 25_Jan_24_23_23/bin/../lib/../lib/libMLIRTargetLLVMIRExport.so.19.0git+0x24c31) #7 0x00007f98ca3c9c13 mlir::translateModuleToLLVMIR(mlir::Operation*, llvm::LLVMContext&, llvm::StringRef) (/work/prbhanda/git/bhanda\ rkar-pranav/build/install_18.0-0-25_Jan_24_23_23/bin/../lib/../lib/libMLIRTargetLLVMIRExport.so.19.0git+0x3bc13) #8 0x00007f98cbdc8fef Fortran::frontend::CodeGenAction::generateLLVMIR() (/work/prbhanda/git/bhandarkar-pranav/build/install_18.0-0-2\ 5_Jan_24_23_23/bin/../lib/libflangFrontend.so.19.0git+0x148fef) #9 0x00007f98cbdcbba0 Fortran::frontend::CodeGenAction::executeAction() (/work/prbhanda/git/bhandarkar-pranav/build/install_18.0-0-25\ _Jan_24_23_23/bin/../lib/libflangFrontend.so.19.0git+0x14bba0) #10 0x00007f98cbcdb091 Fortran::frontend::FrontendAction::execute() (/work/prbhanda/git/bhandarkar-pranav/build/install_18.0-0-25_Jan_\ 24_23_23/bin/../lib/libflangFrontend.so.19.0git+0x5b091) #11 0x00007f98cbccb2e3 Fortran::frontend::CompilerInstance::executeAction(Fortran::frontend::FrontendAction&) (/work/prbhanda/git/bhan\ darkar-pranav/build/install_18.0-0-25_Jan_24_23_23/bin/../lib/libflangFrontend.so.19.0git+0x4b2e3) #12 0x00007f98cc5a6b1b Fortran::frontend::executeCompilerInvocation(Fortran::frontend::CompilerInstance*) (/work/prbhanda/git/bhandark\ ar-pranav/build/install_18.0-0-25_Jan_24_23_23/bin/../lib/libflangFrontendTool.so.19.0git+0x4b1b) #13 0x000055cd42a84c38 fc1_main(llvm::ArrayRef<char const*>, char const*) (/work/prbhanda/git/bhandarkar-pranav/build/install_18.0-0-2\ 5_Jan_24_23_23/bin/flang-new+0x5c38) #14 0x000055cd42a8335d main (/work/prbhanda/git/bhandarkar-pranav/build/install_18.0-0-25_Jan_24_23_23/bin/flang-new+0x435d) #15 0x00007f98c8c29d90 __libc_start_call_main ./csu/../sysdeps/nptl/libc_start_call_main.h:58:16 #16 0x00007f98c8c29e40 call_init ./csu/../csu/libc-start.c:128:20 #17 0x00007f98c8c29e40 __libc_start_main ./csu/../csu/libc-start.c:379:5 #18 0x000055cd42a83865 _start (/work/prbhanda/git/bhandarkar-pranav/build/install_18.0-0-25_Jan_24_23_23/bin/flang-new+0x4865) flang-new: error: unable to execute command: Segmentation fault (core dumped) flang-new: error: flang frontend command failed due to signal (use -v to see invocation) flang-new version 19.0.0git ([email protected]:bhandarkar-pranav/llvm-project.git 2e0ddfc) Target: x86_64-unknown-linux-gnu Thread model: posix ```

cat f.f95
program main
      implicit none
      integer :: N = 5
      integer, dimension(5) :: a
      integer, dimension(5) :: b
      integer :: i
      integer :: target_a = 0
      !$omp task depend(out:a)
      do i = 1, N
         a(i) = i
      end do
      !$omp end task


      !$omp target map(tofrom:target_a) map(tofrom:a)
      do i = 1, N
         target_a = target_a + i
         a(i) = a(i) + i
      end do
      !$omp end target
      print*, target_a
      print*, a
end program main

[bhandarkar-pranav]

Reduced testcase

cat reduced.mlir
module attributes {omp.is_target_device = true } {
  llvm.func @_QQmain() attributes {fir.bindc_name = "main", omp.declare_target = #omp.declaretarget<device_type = (host), capture_clau\se = (to)>} {
    %0 = llvm.mlir.constant(0 : i32) : i32
    %1 = llvm.mlir.constant(1 : i64) : i64
    %2 = llvm.alloca %1 x i32 {bindc_name = "a"} : (i64) -> !llvm.ptr<5>
    %3 = llvm.addrspacecast %2 : !llvm.ptr<5> to !llvm.ptr
    omp.task {
      llvm.store %0, %3 : i32, !llvm.ptr
      omp.terminator
    }
    %4 = omp.map_info var_ptr(%3 : !llvm.ptr, i32) map_clauses(tofrom) capture(ByRef) -> !llvm.ptr {name = "a"}
    omp.target map_entries(%4 -> %arg0 : !llvm.ptr) {
    ^bb0(%arg0: !llvm.ptr):
      %5 = llvm.mlir.constant(5 : i32) : i32
      %6 = llvm.load %arg0  : !llvm.ptr -> i32
      %7 = llvm.add %6, %5  : i32
      llvm.store %7, %arg0  : i32, !llvm.ptr
      omp.terminator
    }
    llvm.return
  }
}

command

mlir-translate` -mlir-to-llvmir reduced.mlir

[tblah]

This works for me with a flang built today. Can this issue be closed?