[flang][openmp] Crash on simd reduction

[psteinfeld]

Here's a test:

$cat bug.f90
real function fastsum(x,y,n) result(r)
  integer,intent(in) :: n
  real,intent(in) :: x(n),y(n)
  integer i
  !$omp simd reduction(+:r)
    do i=1,n
      r = r + (x(i) + y(i))
    end do
  !$omp end simd
end function
$flang-new -fopenmp bug.f90
flang-new: /local/home/psteinfeld/up/llvm-project/llvm/include/llvm/ADT/STLExtra
s.h:865: llvm::detail::zippy<llvm::detail::zip_first, T, U, Args ...> llvm::zip_
equal(T&&, U&&, Args&& ...) [with T = llvm::SmallVector<const Fortran::semantics
::Symbol*>&; U = llvm::ArrayRef<mlir::Value>&; Args = {llvm::ArrayRef<mlir::Bloc
kArgument>&}]: Assertion `all_equal({range_size(t), range_size(u), range_size(ar
gs)...}) && "Iteratees do not have equal length"' failed.
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and i
nclude the crash backtrace.
Stack dump:
0. Program arguments: /local/home/psteinfeld/up/install/bin/flang-new -fc1 
-triple x86_64-unknown-linux-gnu -emit-obj -mrelocation-model pic -pic-level 2 -
pic-is-pie -target-cpu x86-64 -fopenmp -resource-dir /local/home/psteinfeld/up/i
nstall/lib/clang/20 -mframe-pointer=all -o /tmp/bug-939914.o -x f95-cpp-input bu
g.f90
 #0 0x0000562b587ccf4b llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/loc
al/home/psteinfeld/up/install/bin/flang-new+0x2251f4b)
 #1 0x0000562b587ca754 SignalHandler(int) Signals.cpp:0:0
 #2 0x00007fd4dc08b420 __restore_rt (/lib/x86_64-linux-gnu/libpthread.so.0+0x144
20)
 #3 0x00007fd4dbd1f00b raise (/lib/x86_64-linux-gnu/libc.so.6+0x4300b)
 #4 0x00007fd4dbcfe859 abort (/lib/x86_64-linux-gnu/libc.so.6+0x22859)
 #5 0x00007fd4dbcfe729 (/lib/x86_64-linux-gnu/libc.so.6+0x22729)
 #6 0x00007fd4dbd0ffd6 (/lib/x86_64-linux-gnu/libc.so.6+0x33fd6)
 #7 0x0000562b590bb6cf bindEntryBlockArgs(Fortran::lower::AbstractConverter&, ml
ir::omp::BlockArgOpenMPOpInterface, (anonymous namespace)::EntryBlockArgs const&
)::'lambda1'(llvm::ArrayRef<Fortran::semantics::Symbol const*>, llvm::ArrayRef<m
lir::Value>, llvm::ArrayRef<mlir::BlockArgument>)::operator()(llvm::ArrayRef<For
tran::semantics::Symbol const*>, llvm::ArrayRef<mlir::Value>, llvm::ArrayRef<mli
r::BlockArgument>) const (.isra.0) OpenMP.cpp:0:0
 #8 0x0000562b590bba7c bindEntryBlockArgs(Fortran::lower::AbstractConverter&, ml
ir::omp::BlockArgOpenMPOpInterface, (anonymous namespace)::EntryBlockArgs const&
) OpenMP.cpp:0:0
 #9 0x0000562b590bc271 genLoopVars(mlir::Operation*, Fortran::lower::AbstractCon
verter&, mlir::Location&, llvm::ArrayRef<Fortran::semantics::Symbol const*>, llv
m::ArrayRef<std::pair<mlir::omp::BlockArgOpenMPOpInterface, (anonymous namespace
)::EntryBlockArgs const&>>) (.isra.0) OpenMP.cpp:0:0
...

This code previously compiled without emitting any messages. It looks like the problem started happening with update #110267.

[llvmbot]

@llvm/issue-subscribers-flang-ir

Author: Pete Steinfeld (psteinfeld)

Here's a test: ``` $cat bug.f90 real function fastsum(x,y,n) result(r) integer,intent(in) :: n real,intent(in) :: x(n),y(n) integer i !$omp simd reduction(+:r) do i=1,n r = r + (x(i) + y(i)) end do !$omp end simd end function $flang-new -fopenmp bug.f90 flang-new: /local/home/psteinfeld/up/llvm-project/llvm/include/llvm/ADT/STLExtra s.h:865: llvm::detail::zippy<llvm::detail::zip_first, T, U, Args ...> llvm::zip_ equal(T&&, U&&, Args&& ...) [with T = llvm::SmallVector<const Fortran::semantics ::Symbol*>&; U = llvm::ArrayRef<mlir::Value>&; Args = {llvm::ArrayRef<mlir::Bloc kArgument>&}]: Assertion `all_equal({range_size(t), range_size(u), range_size(ar gs)...}) && "Iteratees do not have equal length"' failed. PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and i nclude the crash backtrace. Stack dump: 0. Program arguments: /local/home/psteinfeld/up/install/bin/flang-new -fc1 -triple x86_64-unknown-linux-gnu -emit-obj -mrelocation-model pic -pic-level 2 - pic-is-pie -target-cpu x86-64 -fopenmp -resource-dir /local/home/psteinfeld/up/i nstall/lib/clang/20 -mframe-pointer=all -o /tmp/bug-939914.o -x f95-cpp-input bu g.f90 #0 0x0000562b587ccf4b llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/loc al/home/psteinfeld/up/install/bin/flang-new+0x2251f4b) #1 0x0000562b587ca754 SignalHandler(int) Signals.cpp:0:0 #2 0x00007fd4dc08b420 __restore_rt (/lib/x86_64-linux-gnu/libpthread.so.0+0x144 20) #3 0x00007fd4dbd1f00b raise (/lib/x86_64-linux-gnu/libc.so.6+0x4300b) #4 0x00007fd4dbcfe859 abort (/lib/x86_64-linux-gnu/libc.so.6+0x22859) #5 0x00007fd4dbcfe729 (/lib/x86_64-linux-gnu/libc.so.6+0x22729) #6 0x00007fd4dbd0ffd6 (/lib/x86_64-linux-gnu/libc.so.6+0x33fd6) #7 0x0000562b590bb6cf bindEntryBlockArgs(Fortran::lower::AbstractConverter&, ml ir::omp::BlockArgOpenMPOpInterface, (anonymous namespace)::EntryBlockArgs const& )::'lambda1'(llvm::ArrayRef<Fortran::semantics::Symbol const*>, llvm::ArrayRef<m lir::Value>, llvm::ArrayRef<mlir::BlockArgument>)::operator()(llvm::ArrayRef<For tran::semantics::Symbol const*>, llvm::ArrayRef<mlir::Value>, llvm::ArrayRef<mli r::BlockArgument>) const (.isra.0) OpenMP.cpp:0:0 #8 0x0000562b590bba7c bindEntryBlockArgs(Fortran::lower::AbstractConverter&, ml ir::omp::BlockArgOpenMPOpInterface, (anonymous namespace)::EntryBlockArgs const& ) OpenMP.cpp:0:0 #9 0x0000562b590bc271 genLoopVars(mlir::Operation*, Fortran::lower::AbstractCon verter&, mlir::Location&, llvm::ArrayRef<Fortran::semantics::Symbol const*>, llv m::ArrayRef<std::pair<mlir::omp::BlockArgOpenMPOpInterface, (anonymous namespace )::EntryBlockArgs const&>>) (.isra.0) OpenMP.cpp:0:0 ... ``` This code previously compiled without emitting any messages. It looks like the problem started happening with update #110267.

[skatrak]

This should address it: #111523.

[skatrak]

Can someone check if the issue is resolved?

[tblah]

It is resolved for me