Fixed Expr issue when the ci is a type of GlobalRef

[miniskar]

Error handling if the ci is of type GlobalRef, from which the Expr can be constructed. It also have error handling if the Ci is a different type.

[chriselrod]

Mind adding a test that fails without this change but passes with it?

[miniskar]

It requires Llama2 to be installed. https://github.com/cafaxo/Llama2.jl
Julia version info:

julia> versioninfo()
Julia Version 1.13.0-DEV.298 (Nightly build)
Commit 8b146907373 (2025-03-25 15:26 UTC)
Build Info:
  Official https://julialang.org release
Platform Info:
  OS: Linux (x86_64-linux-gnu)
  CPU: 128 × AMD EPYC 7513 32-Core Processor
  WORD_SIZE: 64
  LLVM: libLLVM-19.1.7 (ORCJIT, znver3)
  GC: Built with stock GC
Threads: 1 default, 1 interactive, 1 GC (on 128 virtual cores)

Here is the test.
File: stories.jl

using Llama2
download("https://huggingface.co/karpathy/tinyllamas/resolve/main/stories42M.bin", "stories42M.bin")
download("https://raw.githubusercontent.com/karpathy/llama2.c/b4bb47bb7baf0a5fb98a131d80b4e1a84ad72597/tokenizer.bin", "tokenizer.bin")
model = load_karpathy_model("stories42M.bin", "tokenizer.bin");
sample(model, "Tim was happy."; temperature = 0.8f0)

It gives below error.

$ julia stories.jl
Precompiling SpecialFunctionsExt finished.
  1 dependency successfully precompiled in 2 seconds. 136 already precompiled.
ERROR: LoadError: TypeError: in typeassert, expected Expr, got a value of type GlobalRef
Stacktrace:
  [1] substitute_broadcast(q::Expr, mod::Symbol, inline::Bool, u₁::Int8, u₂::Int8, v::Int8, threads::Int64, warncheckarg::Int64, safe::Bool)
    @ LoopVectorization ~/.julia/packages/LoopVectorization/tIJUA/src/constructors.jl:70
  [2] turbo_macro(::Module, ::LineNumberNode, ::Expr)
    @ LoopVectorization ~/.julia/packages/LoopVectorization/tIJUA/src/constructors.jl:295
  [3] var"@turbo"(__source__::LineNumberNode, __module__::Module, args::Vararg{Any})
    @ LoopVectorization ~/.julia/packages/LoopVectorization/tIJUA/src/constructors.jl:404
  [4] include(mapexpr::Function, mod::Module, _path::String)
    @ Base ./Base.jl:304
  [5] top-level scope
    @ /noback/Llama2.jl/src/Llama2.jl:31
  [6] include(mapexpr::Function, mod::Module, _path::String)
    @ Base ./Base.jl:304
  [7] top-level scope
    @ /noback/Llama2.jl/stories.jl:1
  [8] include(mod::Module, _path::String)
    @ Base ./Base.jl:303
  [9] exec_options(opts::Base.JLOptions)
    @ Base ./client.jl:328
 [10] _start()
    @ Base ./client.jl:560