# Getting LLVM Bitcode from Julia Script

**URL:** <https://discourse.julialang.org/t/getting-llvm-bitcode-from-julia-script/15249>\
**Category:** New to Julia\
**Tags:** question\
**Created:** [September 20, 2018, 7:20pm UTC](https://discourse.julialang.org/t/getting-llvm-bitcode-from-julia-script/15249 "2018-09-20T19:20:07Z")\
**Posts on this page:** 6\
**Page:** 1

<div class="post-metadata">

**Author:** ![pedramz](https://avatars.discourse-cdn.com/v4/letter/p/ac8455/32.png) [@pedramz](https://discourse.julialang.org/u/pedramz)\
**Post date:** [September 20, 2018, 7:20pm UTC](https://discourse.julialang.org/t/getting-llvm-bitcode-from-julia-script/15249/1 "2018-09-20T19:20:07Z")

</div>

I’m new to Julia and I’m trying to get the LLVM IR or bitcode file of a Julia script. Two ways are mentioned in documents:

1- export JULIA\_LLVM\_ARGS = -print-after-all` dumps IR after each pass.

2- Passing --outout-unopt-bc unopt.bc option to system image build process, which will output the unoptimized IR to the unopt.bc file.

I want the finalized IR and getting IR after each pass is not useful for me. For the second option, as I understand, previous Julia versions accept --output-unopt-bc and --outpu-bc options but version 1.0 does not.

Is there any straightforward way to get the LLVM bitcode file?

---

<div class="post-metadata">

**Author:** ![dpsanders](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/dpsanders/32/3573_2.png) [@dpsanders](https://discourse.julialang.org/u/dpsanders)\
**Post date:** [September 21, 2018, 1:56am UTC](https://discourse.julialang.org/t/getting-llvm-bitcode-from-julia-script/15249/2 "2018-09-21T01:56:07Z")

</div>

Put it in a function and use @code\_llvm

---

<div class="post-metadata">

**Author:** ![maleadt](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/maleadt/32/10097_2.png) [@maleadt](https://discourse.julialang.org/u/maleadt)\
**Post date:** [September 21, 2018, 12:01pm UTC](https://discourse.julialang.org/t/getting-llvm-bitcode-from-julia-script/15249/3 "2018-09-21T12:01:26Z")

</div>

You might want to enable the `dump_module` option, eg. `@code_llvm dump_module=true 1+1`, if you want IR that’s compatible with the rest of LLVM tooling.

---

<div class="post-metadata">

**Author:** ![pedramz](https://avatars.discourse-cdn.com/v4/letter/p/ac8455/32.png) [@pedramz](https://discourse.julialang.org/u/pedramz)\
**Post date:** [September 21, 2018, 10:13pm UTC](https://discourse.julialang.org/t/getting-llvm-bitcode-from-julia-script/15249/4 "2018-09-21T22:13:37Z")

</div>

Is it possible to use the @code\_llvm in a script or it works only for the interactive mode of Julia?

I tried it in the interactive mode and it does not print the IR of all functions which are called in the main function.

---

<div class="post-metadata">

**Author:** ![pedramz](https://avatars.discourse-cdn.com/v4/letter/p/ac8455/32.png) [@pedramz](https://discourse.julialang.org/u/pedramz)\
**Post date:** [September 21, 2018, 10:13pm UTC](https://discourse.julialang.org/t/getting-llvm-bitcode-from-julia-script/15249/5 "2018-09-21T22:13:40Z")

</div>

Thanks but still it does not print the whole code’s IR, it only prints that function’s IR in another way.

---

<div class="post-metadata">

**Author:** ![maleadt](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/maleadt/32/10097_2.png) [@maleadt](https://discourse.julialang.org/u/maleadt)\
**Post date:** [September 22, 2018, 10:04am UTC](https://discourse.julialang.org/t/getting-llvm-bitcode-from-julia-script/15249/6 "2018-09-22T10:04:14Z")

</div>

> [@pedramz](#):
>
> Is it possible to use the @code\_llvm in a script or it works only for the interactive mode of Julia?

Use the `code_llvm` function with the `io` argument set to a IOBuffer.

> [@pedramz](#):
>
> Thanks but still it does not print the whole code’s IR, it only prints that function’s IR in another way.

That’s not true.

```julia
julia> code_llvm(+, Tuple{Int, Int})

; Function +
; Location: int.jl:53
define i64 @"julia_+_33814"(i64, i64) {
top:
  %2 = add i64 %1, %0
  ret i64 %2
}

julia> code_llvm(+, Tuple{Int, Int}; dump_module=true)
; ModuleID = '+'
source_filename = "+"
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128-ni:10:11:12:13"
target triple = "x86_64-unknown-linux-gnu"

%jl_value_t = type opaque

; Function +
; Location: int.jl:53
define i64 @"julia_+_33814"(i64, i64) {
top:
  %2 = add i64 %1, %0
  ret i64 %2
}

define nonnull %jl_value_t addrspace(10)* @"jsys_+_33813"(%jl_value_t addrspace(10)*, %jl_value_t addrspace(10)**, i32) #0 {
top:
  %3 = getelementptr inbounds %jl_value_t addrspace(10)*, %jl_value_t addrspace(10)** %1, i64 1
  %4 = bitcast %jl_value_t addrspace(10)**%3 to i64 addrspace(10)**
  %5 = load i64 addrspace(10)*, i64 addrspace(10)** %4, align 8
  %6 = addrspacecast i64 addrspace(10)* %5 to i64 addrspace(11)*
  %7 = load i64, i64 addrspace(11)* %6, align 8
  %8 = getelementptr inbounds %jl_value_t addrspace(10)*, %jl_value_t addrspace(10)** %1, i64 2
  %9 = bitcast %jl_value_t addrspace(10)**%8 to i64 addrspace(10)**
  %10 = load i64 addrspace(10)*, i64 addrspace(10)** %9, align 8
  %11 = addrspacecast i64 addrspace(10)* %10 to i64 addrspace(11)*
  %12 = load i64, i64 addrspace(11)* %11, align 8
  %13 = call i64 @"julia_+_33814"(i64 %7, i64 %12)
  %14 = call %jl_value_t addrspace(10)* @jl_box_int64(i64 signext %13)
  ret %jl_value_t addrspace(10)* %14
}

declare %jl_value_t addrspace(10)* @jl_box_int64(i64 signext)

attributes #0 = { "thunk" }

!llvm.module.flags = !{!0, !1}
!llvm.dbg.cu = !{!2}

!0 = !{i32 2, !"Dwarf Version", i32 4}
!1 = !{i32 1, !"Debug Info Version", i32 3}
!2 = distinct !DICompileUnit(language: DW_LANG_C89, file: !3, producer: "julia", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !4)
!3 = !DIFile(filename: "int.jl", directory: ".")
!4 = !{}

```