csharp73.cs:
#    3| [Class] StackAllocs
#    5|   5: [Method] Fn
#    5|     -1: [TypeMention] Void
#    6|     4: [BlockStmt] {...}
#    7|       0: [LocalVariableDeclStmt] ... ...;
#    7|         0: [LocalVariableDeclAndInitExpr] Char* arr1 = ...
#    7|           -1: [TypeMention] char*
#    7|           0: [LocalVariableAccess] access to local variable arr1
#    7|           1: [Stackalloc] array creation of type Char*
#    7|             -2: [TypeMention] char*
#    7|               1: [TypeMention] char
#    7|             -1: [ArrayInitializer] { ..., ... }
#    7|               0: [CharLiteral] x
#    7|               1: [CharLiteral] y
#    8|       1: [LocalVariableDeclStmt] ... ...;
#    8|         0: [LocalVariableDeclAndInitExpr] Char* arr2 = ...
#    8|           -1: [TypeMention] char*
#    8|           0: [LocalVariableAccess] access to local variable arr2
#    8|           1: [Stackalloc] array creation of type Char*
#    8|             -2: [TypeMention] char*
#    8|               1: [TypeMention] char
#    8|             -1: [ArrayInitializer] { ..., ... }
#    8|               0: [CharLiteral] x
#    8|             0: [IntLiteral] 1
#    9|       2: [LocalVariableDeclStmt] ... ...;
#    9|         0: [LocalVariableDeclAndInitExpr] Char[] arr3 = ...
#    9|           -1: [TypeMention] Char[]
#    9|           0: [LocalVariableAccess] access to local variable arr3
#    9|           1: [ArrayCreation] array creation of type Char[]
#    9|             -2: [TypeMention] Char[]
#    9|               1: [TypeMention] char
#    9|             -1: [ArrayInitializer] { ..., ... }
#    9|               0: [CharLiteral] x
#   10|       3: [LocalVariableDeclStmt] ... ...;
#   10|         0: [LocalVariableDeclAndInitExpr] Char* arr4 = ...
#   10|           -1: [TypeMention] char*
#   10|           0: [LocalVariableAccess] access to local variable arr4
#   10|           1: [Stackalloc] array creation of type Char*
#   10|             -1: [TypeMention] char*
#   10|               1: [TypeMention] char
#   10|             0: [IntLiteral] 10
#   11|       4: [LocalVariableDeclStmt] ... ...;
#   11|         0: [LocalVariableDeclAndInitExpr] Char[] arr5 = ...
#   11|           -1: [TypeMention] Char[]
#   11|           0: [LocalVariableAccess] access to local variable arr5
#   11|           1: [ArrayCreation] array creation of type Char[]
#   11|             -1: [TypeMention] Char[]
#   11|               1: [TypeMention] char
#   11|             0: [IntLiteral] 10
#   12|       5: [LocalVariableDeclStmt] ... ...;
#   12|         0: [LocalVariableDeclAndInitExpr] Int32* arr6 = ...
#   12|           -1: [TypeMention] int*
#   12|           0: [LocalVariableAccess] access to local variable arr6
#   12|           1: [Stackalloc] array creation of type Int32*
#   12|             -1: [ArrayInitializer] { ..., ... }
#   12|               0: [IntLiteral] 1
#   12|               1: [IntLiteral] 2
#   12|               2: [IntLiteral] 3
#   16| [Class] PinnedReference
#   18|   5: [Method] F
#   18|     -1: [TypeMention] Void
#   19|     4: [BlockStmt] {...}
#   20|       0: [LocalVariableDeclStmt] ... ...;
#   20|         0: [LocalVariableDeclAndInitExpr] Span<Byte> buffer = ...
#   20|           -1: [TypeMention] Span<byte>
#   20|             1: [TypeMention] byte
#   20|           0: [LocalVariableAccess] access to local variable buffer
#   20|           1: [Stackalloc] array creation of type Span<Byte>
#   20|             -1: [TypeMention] Span<byte>
#   20|               1: [TypeMention] byte
#   20|             0: [IntLiteral] 10
#   22|       1: [LocalVariableDeclStmt] ... ...;
#   22|         0: [LocalVariableDeclAndInitExpr] Span<Int32> t = ...
#   22|           -1: [TypeMention] Span<int>
#   22|             1: [TypeMention] int
#   22|           0: [LocalVariableAccess] access to local variable t
#   22|           1: [OperatorCall] call to operator implicit conversion
#   22|             0: [ArrayCreation] array creation of type Int32[]
#   22|               -1: [TypeMention] Int32[]
#   22|                 1: [TypeMention] int
#   22|               0: [IntLiteral] 10
#   25|       2: [BlockStmt] {...}
#   30| [Class] UnmanagedConstraint`1
#-----|   1: (Type parameters)
#   30|     0: [TypeParameter] T
#   34| [Class] EnumConstraint`1
#-----|   1: (Type parameters)
#   34|     0: [TypeParameter] T
#   38| [Class] DelegateConstraint`1
#-----|   1: (Type parameters)
#   38|     0: [TypeParameter] T
#   42| [Class] ExpressionVariables
#   44|   4: [InstanceConstructor] ExpressionVariables
#-----|     2: (Parameters)
#   44|       0: [Parameter] x
#   44|         -1: [TypeMention] int
#   45|     4: [BlockStmt] {...}
#   46|       0: [ExprStmt] ...;
#   46|         0: [AssignExpr] ... = ...
#   46|           0: [ParameterAccess] access to parameter x
#   46|           1: [IntLiteral] 5
#   49|   5: [InstanceConstructor] ExpressionVariables
#   49|     3: [ConstructorInitializer] call to constructor ExpressionVariables
#   49|       0: [LocalVariableAccess,LocalVariableDeclExpr] Int32 x
#   50|     4: [BlockStmt] {...}
#   51|       0: [ExprStmt] ...;
#   51|         0: [MethodCall] call to method WriteLine
#   51|           -1: [TypeAccess] access to type Console
#   51|             0: [TypeMention] Console
#   51|           0: [InterpolatedStringExpr] $"..."
#   51|             0: [StringLiteralUtf16] "x is "
#   51|             1: [InterpolatedStringInsertExpr] {...}
#   51|               0: [LocalVariableAccess] access to local variable x