# This file is a part of Julia. License is MIT: https://julialang.org/license

# tests for codegen and optimizations

using Random
using InteractiveUtils

const opt_level = Base.JLOptions().opt_level
const coverage = (Base.JLOptions().code_coverage > 0) || (Base.JLOptions().malloc_log > 0)
const Iptr = sizeof(Int) == 8 ? "i64" : "i32"

# `_dump_function` might be more efficient but it doesn't really matter here...
get_llvm(@nospecialize(f), @nospecialize(t), raw=true, dump_module=false, optimize=true) =
    sprint(code_llvm, f, t, raw, dump_module, optimize)

if opt_level > 0
    # Make sure getptls call is removed at IR level with optimization on
    @test !occursin(" call ", get_llvm(identity, Tuple{String}))
end

jl_string_ptr(s::String) = ccall(:jl_string_ptr, Ptr{UInt8}, (Any,), s)
core_sizeof(o) = Core.sizeof(o)
function test_loads_no_call(ir, load_types)
    in_function = false
    load_idx = 1
    for line in eachline(IOBuffer(ir))
        if !in_function
            if startswith(line, "define ")
                in_function = true
            end
            continue
        end
        @test !occursin(" call ", line)
        load_split = split(line, " load ", limit=2)
        if !coverage && length(load_split) >= 2
            @test load_idx <= length(load_types)
            if load_idx <= length(load_types)
                @test startswith(load_split[2], "$(load_types[load_idx]),")
            end
            load_idx += 1
        end
        if startswith(line, "}")
            break
        end
    end
    if !coverage
        @test load_idx == length(load_types) + 1
    end
end

# This function tests if functions are output when compiled if jl_dump_compiles is enabled.
# Have to go through pains with recursive function (eval probably not required) to make sure
# that inlining won't happen.
function test_jl_dump_compiles()
    tfile = tempname()
    io = open(tfile, "w")
    @eval(test_jl_dump_compiles_internal(x) = x)
    ccall(:jl_dump_compiles, Cvoid, (Ptr{Cvoid},), io.handle)
    @eval test_jl_dump_compiles_internal(1)
    ccall(:jl_dump_compiles, Cvoid, (Ptr{Cvoid},), C_NULL)
    close(io)
    tstats = stat(tfile)
    tempty = tstats.size == 0
    rm(tfile)
    @test tempty == false
end

# This function tests if a toplevel thunk is output if jl_dump_compiles is enabled.
# The eval statement creates the toplevel thunk.
function test_jl_dump_compiles_toplevel_thunks()
    tfile = tempname()
    io = open(tfile, "w")
    # Make sure to cause compilation of the eval function
    # before calling it below.
    Core.eval(Main, Any[:(nothing)][1])
    GC.enable(false)  # avoid finalizers to be compiled
    topthunk = Meta.lower(Main, :(for i in 1:10; end))
    ccall(:jl_dump_compiles, Cvoid, (Ptr{Cvoid},), io.handle)
    Core.eval(Main, topthunk)
    ccall(:jl_dump_compiles, Cvoid, (Ptr{Cvoid},), C_NULL)
    close(io)
    GC.enable(true)
    tstats = stat(tfile)
    tempty = tstats.size == 0
    rm(tfile)
    @test tempty == true
end

if opt_level > 0
    # Make sure `jl_string_ptr` is inlined
    @test !occursin(" call ", get_llvm(jl_string_ptr, Tuple{String}))
    # Make sure `Core.sizeof` call is inlined
    s = "aaa"
    @test jl_string_ptr(s) == pointer_from_objref(s) + sizeof(Int)
    # String
    test_loads_no_call(get_llvm(core_sizeof, Tuple{String}), [Iptr])
    # String
    test_loads_no_call(get_llvm(core_sizeof, Tuple{Core.SimpleVector}), [Iptr])
    # Array
    test_loads_no_call(get_llvm(core_sizeof, Tuple{Vector{Int}}), [Iptr])
    # As long as the eltype is known we don't need to load the elsize
    test_loads_no_call(get_llvm(core_sizeof, Tuple{Array{Any}}), [Iptr])
    # Check that we load the elsize
    test_loads_no_call(get_llvm(core_sizeof, Tuple{Vector}), [Iptr, "i16"])
    # Primitive Type size should be folded to a constant
    test_loads_no_call(get_llvm(core_sizeof, Tuple{Ptr}), String[])

    test_jl_dump_compiles()
    test_jl_dump_compiles_toplevel_thunks()
end

# Make sure we will not elide the allocation
@noinline create_ref1() = Ref(1)
function pointer_not_safepoint()
    a = create_ref1()
    unsafe_store!(Ptr{Int}(pointer_from_objref(a)), 3)
    return a[]
end
@test pointer_not_safepoint() == 3

# The current memcmp threshold is 512bytes, make sure this struct has the same size on
# 32bits and 64bits
struct LargeStruct
    x::NTuple{1024,Int8}
    LargeStruct() = new()
end

const large_struct = LargeStruct()
@noinline create_ref_struct() = Ref(large_struct)
function compare_large_struct(a)
    b = create_ref_struct()
    if a[] === b[]
        b[].x[1]
    else
        a[].x[2]
    end
end

mutable struct MutableStruct
    a::Int
    MutableStruct() = new()
end

breakpoint_mutable(a::MutableStruct) = ccall(:jl_breakpoint, Cvoid, (Ref{MutableStruct},), a)

# Allocation with uninitialized field as gcroot
mutable struct BadRef
    x::MutableStruct
    y::MutableStruct
    BadRef(x) = new(x)
end
Base.cconvert(::Type{Ptr{BadRef}}, a::MutableStruct) = BadRef(a)
Base.unsafe_convert(::Type{Ptr{BadRef}}, ar::BadRef) = Ptr{BadRef}(pointer_from_objref(ar.x))

breakpoint_badref(a::MutableStruct) = ccall(:jl_breakpoint, Cvoid, (Ptr{BadRef},), a)

struct PtrStruct
    a::Ptr{Cvoid}
    b::Int
end

mutable struct RealStruct
    a::Float64
    b::Int
end

function Base.cconvert(::Type{Ref{PtrStruct}}, a::RealStruct)
    (a, Ref(PtrStruct(pointer_from_objref(a), a.b)))
end
Base.unsafe_convert(::Type{Ref{PtrStruct}}, at::Tuple) =
    Base.unsafe_convert(Ref{PtrStruct}, at[2])

breakpoint_ptrstruct(a::RealStruct) =
    ccall(:jl_breakpoint, Cvoid, (Ref{PtrStruct},), a)

@noinline r_typeassert(c) = c ? (1,1) : nothing
function f_typeassert(c)
    r_typeassert(c)::Tuple
end
@test !occursin("jl_subtype", get_llvm(f_typeassert, Tuple{Bool}))

if opt_level > 0
    @test !occursin("%gcframe", get_llvm(pointer_not_safepoint, Tuple{}))
    compare_large_struct_ir = get_llvm(compare_large_struct, Tuple{typeof(create_ref_struct())})
    @test occursin("call i32 @memcmp(", compare_large_struct_ir) || occursin("call i32 @bcmp(", compare_large_struct_ir)
    @test !occursin("%gcframe", compare_large_struct_ir)

    @test occursin("jl_gc_pool_alloc", get_llvm(MutableStruct, Tuple{}))
    breakpoint_mutable_ir = get_llvm(breakpoint_mutable, Tuple{MutableStruct})
    @test !occursin("%gcframe", breakpoint_mutable_ir)
    @test !occursin("jl_gc_pool_alloc", breakpoint_mutable_ir)

    breakpoint_badref_ir = get_llvm(breakpoint_badref, Tuple{MutableStruct})
    @test !occursin("%gcframe", breakpoint_badref_ir)
    @test !occursin("jl_gc_pool_alloc", breakpoint_badref_ir)

    breakpoint_ptrstruct_ir = get_llvm(breakpoint_ptrstruct, Tuple{RealStruct})
    @test !occursin("%gcframe", breakpoint_ptrstruct_ir)
    @test !occursin("jl_gc_pool_alloc", breakpoint_ptrstruct_ir)
end

function two_breakpoint(a::Float64)
    ccall(:jl_breakpoint, Cvoid, (Ref{Float64},), a)
    ccall(:jl_breakpoint, Cvoid, (Ref{Float64},), a)
end

function load_dummy_ref(x::Int)
    r = Ref{Int}(x)
    GC.@preserve r begin
        unsafe_load(Ptr{Int}(pointer_from_objref(r)))
    end
end

if opt_level > 0
    breakpoint_f64_ir = get_llvm((a)->ccall(:jl_breakpoint, Cvoid, (Ref{Float64},), a),
                                 Tuple{Float64})
    @test !occursin("jl_gc_pool_alloc", breakpoint_f64_ir)
    breakpoint_any_ir = get_llvm((a)->ccall(:jl_breakpoint, Cvoid, (Ref{Any},), a),
                                 Tuple{Float64})
    @test occursin("jl_gc_pool_alloc", breakpoint_any_ir)
    two_breakpoint_ir = get_llvm(two_breakpoint, Tuple{Float64})
    @test !occursin("jl_gc_pool_alloc", two_breakpoint_ir)
    @test occursin("llvm.lifetime.end", two_breakpoint_ir)

    @test load_dummy_ref(1234) === 1234
    load_dummy_ref_ir = get_llvm(load_dummy_ref, Tuple{Int})
    @test !occursin("jl_gc_pool_alloc", load_dummy_ref_ir)
    # Hopefully this is reliable enough. LLVM should be able to optimize this to a direct return.
    @test occursin("ret $Iptr %0", load_dummy_ref_ir)
end

# Issue 22770
let was_gced = false
    @noinline make_tuple(x) = tuple(x)
    @noinline use(x) = ccall(:jl_breakpoint, Cvoid, ())
    @noinline assert_not_gced() = @test !was_gced

    function foo22770()
        b = Ref(2)
        finalizer(x -> was_gced = true, b)
        y = make_tuple(b)
        x = y[1]
        a = Ref(1)
        use(x); use(a); use(y)
        c = Ref(3)
        GC.gc()
        assert_not_gced()
        use(x)
        use(c)
    end
    foo22770()
    GC.gc()
    @test was_gced
end

function egal_svecs()
    a = Core.svec(:a, :b)
    b = Core.svec(:a, :b)
    a === b
end
@test egal_svecs()
@test Core.svec(:a, :b) === Core.svec(:a, :b)

# issue #22582
function issue22582!(a::AbstractArray, b)
    len = length(a)
    if b
        ccall(:jl_array_grow_end, Cvoid, (Any, Csize_t), a, 1)
    end
    return len
end
let c = [1,2,3]
    len1 = length(c)
    len2 = issue22582!(c, true)
    @test len1 == len2
end

# PR #23595
@generated f23595(g, args...) = Expr(:call, :g, Expr(:(...), :args))
x23595 = rand(1)
@test f23595(Core.arrayref, true, x23595, 1) == x23595[]

# Issue #22421
@noinline f22421_1(x) = x[] + 1
@noinline f22421_2(x) = x[] + 2
@noinline f22421_3(x, y, z, v) = x[] + y[] + z[] + v
function g22421_1(x, y, b)
    # Most likely generates a branch with phi node
    if b
        z = x
        v = f22421_1(y)
    else
        z = y
        v = f22421_2(x)
    end
    return f22421_3(x, y, z, v)
end
function g22421_2(x, y, b)
    # Most likely generates a select
    return f22421_3(x, y, b ? x : y, 1)
end

struct A24108
    x::Vector{Int}
end
struct B24108
    x::A24108
end
@noinline f24108(x) = length(x)
# Test no gcframe is allocated for `x.x.x` even though `x.x` isn't live at the call site
g24108(x::B24108) = f24108(x.x.x)

@test g22421_1(Ref(1), Ref(2), true) === 7
@test g22421_1(Ref(3), Ref(4), false) === 16
@test g22421_2(Ref(5), Ref(6), true) === 17
@test g22421_2(Ref(7), Ref(8), false) === 24

if opt_level > 0
    @test !occursin("%gcframe",
                    get_llvm(g22421_1, Tuple{Base.RefValue{Int},Base.RefValue{Int},Bool}))
    @test !occursin("%gcframe",
                    get_llvm(g22421_2, Tuple{Base.RefValue{Int},Base.RefValue{Int},Bool}))
    @test !occursin("%gcframe", get_llvm(g24108, Tuple{B24108}))
end

str_22330 = """
Base.convert(::Type{Array{T,n}}, a::Array) where {T<:Number,n} =
             copyto!(Array{T,n}(undef, size(a)), a)

empty(Dict(),  Pair{Union{},Union{}})
"""
mktemp() do f_22330, _
    write(f_22330, str_22330)
    @test success(`$(Base.julia_cmd()) --startup-file=no $f_22330`)
end

# Alias scope
macro aliasscope(body)
    sym = gensym()
    esc(quote
        $(Expr(:aliasscope))
        $sym = $body
        $(Expr(:popaliasscope))
        $sym
    end)
end

struct Const{T<:Array}
    a::T
end

@eval Base.getindex(A::Const, i1::Int) = Core.const_arrayref($(Expr(:boundscheck)), A.a, i1)
@eval Base.getindex(A::Const, i1::Int, i2::Int, I::Int...) =  (Base.@_inline_meta; Core.const_arrayref($(Expr(:boundscheck)), A.a, i1, i2, I...))

function foo31018!(a, b)
    @aliasscope for i in eachindex(a, b)
        a[i] = Const(b)[i]
    end
end
io = IOBuffer()
code_llvm(io, foo31018!, Tuple{Vector{Int}, Vector{Int}}, optimize=false, raw=true, dump_module=true)
str = String(take!(io))
@test occursin("alias.scope", str)
@test occursin("aliasscope", str)
@test occursin("noalias", str)

# Issue #10208 - Unnecessary boxing for calling objectid
struct FooDictHash{T}
    x::T
end

function f_dict_hash_alloc()
    d = Dict{FooDictHash{Int},Int}()
    for i in 1:10000
        d[FooDictHash(i)] = i+1
    end
    d
end

function g_dict_hash_alloc()
    d = Dict{Int,Int}()
    for i in 1:10000
        d[i] = i+1
    end
    d
end
# Warm up
f_dict_hash_alloc(); g_dict_hash_alloc();
@test (@allocated f_dict_hash_alloc()) == (@allocated g_dict_hash_alloc())

# returning an argument shouldn't alloc a new box
@noinline f33829(x) = (global called33829 = true; x)
g33829() = @allocated Base.inferencebarrier(f33829)(1.1,)
g33829() # warm up
@test (@allocated g33829()) == 0
@test called33829 # make sure there was a global side effect so it's hard for this call to simply be removed
let src = get_llvm(f33829, Tuple{Float64}, true, true)
    @test occursin(r"call [^(]*double @", src)
    @test !occursin(r"call [^(]*\{}", src)
end

let io = IOBuffer()
    # Test for the f(args...) = g(args...) generic codegen optimization
    code_llvm(io, Base.vect, Tuple{Vararg{Union{Float64, Int64}}})
    @test !occursin("__apply", String(take!(io)))
end

function f1_30093(r)
    while r[]>0
        try
        finally
        end
    end
end

@test f1_30093(Ref(0)) == nothing

# issue 33590
function f33590(b, x)
    y = b ? nothing : (x[1] + 1,)
    return something(ifelse(b, x, y))
end
@test f33590(true, (3,)) == (3,)
@test f33590(false, (3,)) == (4,)

# issue 29864
const c29864 = VecElement{Union{Int,Nothing}}(2)
@noinline f29864() = c29864
@noinline g29864() = VecElement{Union{Int,Nothing}}(3)
@test f29864().value === 2
@test g29864().value === 3

# test sret pointing into a struct containing a tracked pointer
# reduced from TerminalLoggers/ProgressLogging
const _PROGRESS_LOGGING_UUID_NS_test = Base.UUID("1e962757-ea70-431a-b9f6-aadf988dcb7f")
_asuuid_test(id) = Base.uuid5(_PROGRESS_LOGGING_UUID_NS_test, repr(id))
@noinline _handle_progress_test(progress) = progress
function _handle_message_test()
    progress = (_asuuid_test(:id), "name")
    return _handle_progress_test(progress)
end
@test _handle_message_test() isa Tuple{Base.UUID, String}

@testset "#30739" begin
    ifelsetuple(n::Integer, k::Integer, f, g) = ntuple(i -> (i <= k ? f : g), n)
    f(x) = x^2; g(x) = x^3;
    a = [1]; b = [2]
    @test ifelsetuple(5, 3, a, b) == ([1], [1], [1], [2], [2])
end

@testset "#36422" begin
    str_36422 = "using InteractiveUtils; code_llvm(Base.ht_keyindex, (Dict{NTuple{65,Int64},Nothing}, NTuple{65,Int64}))"
    @test success(`$(Base.julia_cmd()) --startup-file=no -e $str_36422`)
end

@noinline g37262(x) = (x ? error("intentional") : (0x1, "v", "1", ".", "2"))
function f37262(x)
    try
        GC.safepoint()
    catch
        GC.safepoint()
    end
    try
        GC.gc()
        return g37262(x)
    catch ex
        GC.gc()
    finally
        GC.gc()
    end
end
@testset "#37262" begin
    str = "store volatile { i8, {}*, {}*, {}*, {}* } zeroinitializer, { i8, {}*, {}*, {}*, {}* }* %phic"
    llvmstr = get_llvm(f37262, (Bool,), false, false, false)
    @test contains(llvmstr, str) || llvmstr
    @test f37262(Base.inferencebarrier(true)) === nothing
end

# issue #37671
let d = Dict((:a,) => 1, (:a, :b) => 2)
    @test d[(:a,)] == 1
    @test d[(:a, :b)] == 2
end

# issue #37880
primitive type Has256Bits 256 end
let x = reinterpret(Has256Bits, [0xfcdac822cac89d82de4f9b3326da8294, 0x6ebac4d5982880ca703c57e37657f1ee])[]
    shifted = [0xeefcdac822cac89d82de4f9b3326da82, 0x006ebac4d5982880ca703c57e37657f1]
    f(x) = Base.lshr_int(x, 0x8)
    @test reinterpret(UInt128, [f(x)]) == shifted
    @test reinterpret(UInt128, [Base.lshr_int(x, 0x8)]) == shifted
    g(x) = Base.ashr_int(x, 0x8)
    @test reinterpret(UInt128, [g(x)]) == shifted
    @test reinterpret(UInt128, [Base.ashr_int(x, 0x8)]) == shifted
    lshifted = [0xdac822cac89d82de4f9b3326da829400, 0xbac4d5982880ca703c57e37657f1eefc]
    h(x) = Base.shl_int(x, 0x8)
    @test reinterpret(UInt128, [h(x)]) == lshifted
    @test reinterpret(UInt128, [Base.shl_int(x, 0x8)]) == lshifted
end

# issue #37872
let f(@nospecialize(x)) = x===Base.ImmutableDict(Int128=>:big)
    @test !f(Dict(Int=>Int))
end

# issue #37974
primitive type UInt24 24 end
let a = Core.Intrinsics.trunc_int(UInt24, 3),
    f(t) = t[2]
    @test f((a, true)) === true
    @test f((a, false)) === false
    @test sizeof(Tuple{UInt24,Bool}) == 8
    @test sizeof(UInt24) == 3
    @test sizeof(Union{UInt8,UInt24}) == 3
    @test sizeof(Base.RefValue{Union{UInt8,UInt24}}) == 8
end

# issue #39232
function f39232(a)
    z = Any[]
    for (i, ai) in enumerate(a)
        push!(z, ai)
    end
    return z
end
@test f39232((+, -)) == Any[+, -]

@testset "GC.@preserve" begin
    # main use case
    function f1(cond)
        val = [1]
        GC.@preserve val begin end
    end
    @test occursin("llvm.julia.gc_preserve_begin", get_llvm(f1, Tuple{Bool}, true, false, false))

    # stack allocated objects (JuliaLang/julia#34241)
    function f3(cond)
        val = ([1],)
        GC.@preserve val begin end
    end
    @test occursin("llvm.julia.gc_preserve_begin", get_llvm(f3, Tuple{Bool}, true, false, false))

    # unions of immutables (JuliaLang/julia#39501)
    function f2(cond)
        val = cond ? 1 : 1f0
        GC.@preserve val begin end
    end
    @test !occursin("llvm.julia.gc_preserve_begin", get_llvm(f2, Tuple{Bool}, true, false, false))
    # make sure the fix for the above doesn't regress #34241
    function f4(cond)
        val = cond ? ([1],) : ([1f0],)
        GC.@preserve val begin end
    end
    @test occursin("llvm.julia.gc_preserve_begin", get_llvm(f4, Tuple{Bool}, true, false, false))
end

# issue #32843
function f32843(vals0, v)
    (length(vals0) > 1) && (vals = v[1])
    (length(vals0) == 1 && vals0[1]==1) && (vals = 1:2)
    vals
end
@test_throws UndefVarError f32843([6], Vector[[1]])

# issue #40855, struct constants with union fields
@enum T40855 X40855
struct A40855
    d::Union{Nothing, T40855}
    b::Union{Nothing, Int}
end
g() = string(A40855(X40855, 1))
@test g() == "$(@__MODULE__).A40855($(@__MODULE__).X40855, 1)"

# issue #40612
f40612(a, b) = a|b === a|b
g40612(a, b) = a[]|a[] === b[]|b[]
@test f40612(true, missing)
@test !g40612(Union{Bool,Missing}[missing], Union{Bool,Missing}[true])
@test !g40612(Union{Bool,Missing}[false], Union{Bool,Missing}[true])
@test g40612(Union{Bool,Missing}[missing], Union{Bool,Missing}[missing])
@test g40612(Union{Bool,Missing}[true], Union{Bool,Missing}[true])
@test g40612(Union{Bool,Missing}[false], Union{Bool,Missing}[false])

# issue #41438
struct A41438{T}
  x::Ptr{T}
end
struct B41438{T}
  x::T
end
f41438(y) = y[].x
@test A41438.body.layout != C_NULL
@test B41438.body.layout === C_NULL
@test f41438(Ref{A41438}(A41438(C_NULL))) === C_NULL
@test f41438(Ref{B41438}(B41438(C_NULL))) === C_NULL

const S41438 = Pair{Any, Ptr{T}} where T
g41438() = Array{S41438,1}(undef,1)[1].first
get_llvm(g41438, ()); # cause allocation of layout
@test S41438.body.layout != C_NULL
@test !Base.datatype_pointerfree(S41438.body)
@test S41438{Int}.layout != C_NULL
@test !Base.datatype_pointerfree(S41438{Int})


# issue #43303
struct A43303{T}
    x::Pair{Ptr{T},Ptr{T}}
end
@test A43303.body.layout != C_NULL
@test isbitstype(A43303{Int})
@test A43303.body.types[1].layout != C_NULL

# issue #41157
f41157(a, b) = a[1] = b[1]
@test_throws BoundsError f41157(Tuple{Int}[], Tuple{Union{}}[])

# issue #41096
struct Modulate41096{M<:Union{Function, Val{true}, Val{false}}, id}
    modulate::M
    Modulate41096(id::Symbol, modulate::Function) = new{typeof(modulate), id}(modulate)
    Modulate41096(id::Symbol, modulate::Bool=true) = new{Val{modulate}, id}(modulate|>Val)
end
@inline ismodulatable41096(modulate::Modulate41096) = ismodulatable41096(typeof(modulate))
@inline ismodulatable41096(::Type{<:Modulate41096{Val{B}}}) where B = B
@inline ismodulatable41096(::Type{<:Modulate41096{<:Function}}) = true

mutable struct Term41096{I, M<:Modulate41096}
    modulate::M
    Term41096{I}(modulate::Modulate41096) where I = new{I, typeof(modulate)}(modulate)
end
@inline ismodulatable41096(term::Term41096) = ismodulatable41096(typeof(term))
@inline ismodulatable41096(::Type{<:Term41096{I, M} where I}) where M = ismodulatable41096(M)

function newexpand41096(gen, name::Symbol)
    flag = ismodulatable41096(getfield(gen, name))
    if flag
        return true
    else
        return false
    end
end

t41096 = Term41096{:t}(Modulate41096(:t, false))
μ41096 = Term41096{:μ}(Modulate41096(:μ, false))
U41096 = Term41096{:U}(Modulate41096(:U, false))

@test !newexpand41096((t=t41096, μ=μ41096, U=U41096), :U)

# issue #42645
mutable struct A42645{T}
    x::Bool
    function A42645(a::Vector{T}) where T
        r = new{T}()
        r.x = false
        return r
    end
end
mutable struct B42645{T}
  y::A42645{T}
end
x42645 = 1
function f42645()
  res = B42645(A42645([x42645]))
  res.y = A42645([x42645])
  res.y.x = true
  res
end
@test ((f42645()::B42645).y::A42645{Int}).x

# issue #43123
@noinline cmp43123(a::Some, b::Some) = something(a) === something(b)
@noinline cmp43123(a, b) = a[] === b[]
@test cmp43123(Some{Function}(+), Some{Union{typeof(+), typeof(-)}}(+))
@test !cmp43123(Some{Function}(+), Some{Union{typeof(+), typeof(-)}}(-))
@test cmp43123(Ref{Function}(+), Ref{Union{typeof(+), typeof(-)}}(+))
@test !cmp43123(Ref{Function}(+), Ref{Union{typeof(+), typeof(-)}}(-))
@test cmp43123(Function[+], Union{typeof(+), typeof(-)}[+])
@test !cmp43123(Function[+], Union{typeof(+), typeof(-)}[-])
