[flang] SimplifyIntrinsics pass asserts in findShape

[vzakhari]

FIR produced from this Fortran code:

subroutine foo(a, v)
  real, allocatable :: a(:, :)
  REAL :: v(:)
  v = SUM(a,DIM=1)
end subroutine foo

FIR to reproduce the issue:

module attributes {fir.defaultkind = "a1c4d8i4l4r4", fir.kindmap = "", llvm.target_triple = "x86_64-unknown-linux-gnu"} {
  func.func @_QPfoo(%arg0: !fir.ref<!fir.box<!fir.heap<!fir.array<?x?xf32>>>> {fir.bindc_name = "a"}, %arg1: !fir.box<!fir.array<?xf32>> {fir.bindc_name = "v"}) {
    %0 = fir.alloca !fir.box<!fir.heap<!fir.array<?xf32>>>
    %c0 = arith.constant 0 : index
    %1:3 = fir.box_dims %arg1, %c0 : (!fir.box<!fir.array<?xf32>>, index) -> (index, index, index)
    %2 = fir.array_load %arg1 : (!fir.box<!fir.array<?xf32>>) -> !fir.array<?xf32>
    %3 = fir.load %arg0 : !fir.ref<!fir.box<!fir.heap<!fir.array<?x?xf32>>>>
    %c0_0 = arith.constant 0 : index
    %4:3 = fir.box_dims %3, %c0_0 : (!fir.box<!fir.heap<!fir.array<?x?xf32>>>, index) -> (index, index, index)
    %c1 = arith.constant 1 : index
    %5:3 = fir.box_dims %3, %c1 : (!fir.box<!fir.heap<!fir.array<?x?xf32>>>, index) -> (index, index, index)
    %6 = fir.box_addr %3 : (!fir.box<!fir.heap<!fir.array<?x?xf32>>>) -> !fir.heap<!fir.array<?x?xf32>>
    %7 = fir.shape_shift %4#0, %4#1, %5#0, %5#1 : (index, index, index, index) -> !fir.shapeshift<2>
    %8 = fir.embox %6(%7) : (!fir.heap<!fir.array<?x?xf32>>, !fir.shapeshift<2>) -> !fir.box<!fir.array<?x?xf32>>
    %c1_i32 = arith.constant 1 : i32
    %9 = fir.absent !fir.box<i1>
    %10 = fir.zero_bits !fir.heap<!fir.array<?xf32>>
    %c0_1 = arith.constant 0 : index
    %11 = fir.shape %c0_1 : (index) -> !fir.shape<1>
    %12 = fir.embox %10(%11) : (!fir.heap<!fir.array<?xf32>>, !fir.shape<1>) -> !fir.box<!fir.heap<!fir.array<?xf32>>>
    fir.store %12 to %0 : !fir.ref<!fir.box<!fir.heap<!fir.array<?xf32>>>>
    %13 = fir.address_of(@_QQcl.2E2F7474742E66393000) : !fir.ref<!fir.char<1,10>>
    %c4_i32 = arith.constant 4 : i32
    %14 = fir.convert %0 : (!fir.ref<!fir.box<!fir.heap<!fir.array<?xf32>>>>) -> !fir.ref<!fir.box<none>>
    %15 = fir.convert %8 : (!fir.box<!fir.array<?x?xf32>>) -> !fir.box<none>
    %16 = fir.convert %13 : (!fir.ref<!fir.char<1,10>>) -> !fir.ref<i8>
    %17 = fir.convert %9 : (!fir.box<i1>) -> !fir.box<none>
    %18 = fir.call @_FortranASumDim(%14, %15, %c1_i32, %16, %c4_i32, %17) : (!fir.ref<!fir.box<none>>, !fir.box<none>, i32, !fir.ref<i8>, i32, !fir.box<none>) -> none
    %19 = fir.load %0 : !fir.ref<!fir.box<!fir.heap<!fir.array<?xf32>>>>
    %c0_2 = arith.constant 0 : index
    %20:3 = fir.box_dims %19, %c0_2 : (!fir.box<!fir.heap<!fir.array<?xf32>>>, index) -> (index, index, index)
    %21 = fir.box_addr %19 : (!fir.box<!fir.heap<!fir.array<?xf32>>>) -> !fir.heap<!fir.array<?xf32>>
    %22 = fir.shape_shift %20#0, %20#1 : (index, index) -> !fir.shapeshift<1>
    %23 = fir.array_load %21(%22) : (!fir.heap<!fir.array<?xf32>>, !fir.shapeshift<1>) -> !fir.array<?xf32>
    %c1_3 = arith.constant 1 : index
    %c0_4 = arith.constant 0 : index
    %24 = arith.subi %1#1, %c1_3 : index
    %25 = fir.do_loop %arg2 = %c0_4 to %24 step %c1_3 unordered iter_args(%arg3 = %2) -> (!fir.array<?xf32>) {
      %26 = fir.array_fetch %23, %arg2 : (!fir.array<?xf32>, index) -> f32
      %27 = fir.array_update %arg3, %26, %arg2 : (!fir.array<?xf32>, f32, index) -> !fir.array<?xf32>
      fir.result %27 : !fir.array<?xf32>
    }
    fir.array_merge_store %2, %25 to %arg1 : !fir.array<?xf32>, !fir.array<?xf32>, !fir.box<!fir.array<?xf32>>
    fir.freemem %21 : !fir.heap<!fir.array<?xf32>>
    return
  }
  func.func private @_FortranASumDim(!fir.ref<!fir.box<none>>, !fir.box<none>, i32, !fir.ref<i8>, i32, !fir.box<none>) -> none attributes {fir.runtime}
  fir.global linkonce @_QQcl.2E2F7474742E66393000 constant : !fir.char<1,10> {
    %0 = fir.string_lit "./ttt.f90\00"(10) : !fir.char<1,10>
    fir.has_value %0 : !fir.char<1,10>
  }
}

fir-opt --simplify-intrinsics ttt.fir:

 #9 0x0000000001539f0d llvm::MutableArrayRef<mlir::OpOperand>::operator[](unsigned long) const /local/home/szakharin/llvm-project/llvm/include/llvm/ADT/ArrayRef.h:0:7
#10 0x0000000001539da6 mlir::Operation::getOpOperand(unsigned int) /local/home/szakharin/llvm-project/llvm/../mlir/include/mlir/IR/Operation.h:306:5
#11 0x0000000001539d2b mlir::Operation::getOperand(unsigned int) /local/home/szakharin/llvm-project/llvm/../mlir/include/mlir/IR/Operation.h:267:61
#12 0x000000000174654f findShape(mlir::Value) /local/home/szakharin/llvm-project/flang/lib/Optimizer/Transforms/SimplifyIntrinsics.cpp:305:20

It fails to getOperand(0) on %0 = fir.alloca !fir.box<!fir.heap<!fir.array<?xf32>>>.

[vzakhari]

@Leporacanthicus FYI

[llvmbot]

@llvm/issue-subscribers-flang-ir

[Leporacanthicus]

Fix for review here:
https://reviews.llvm.org/D131671

[Leporacanthicus]

I believe this is fixed as of 7267860