LLVM IR hello world

New to topics? Read the documentation here!
Top articles Latest articles+ New article in topic
LLVM IR hello world by Ciro Santilli 34 Updated 2024-12-15 +Created 1970-01-01
Example: llvm/hello.ll adapted from: llvm.org/docs/LangRef.html#module-structure but without double newline.
To execute it as mentioned at github.com/dfellis/llvm-hello-world we can either use their crazy assembly interpreter, tested on Ubuntu 22.10:
sudo apt install llvm-runtime
lli hello.ll
This seems to use puts from the C standard library.
Or we can Lower it to assembly of the local machine:
sudo apt install llvm
llc hello.ll
which produces:
hello.s
and then we can assemble link and run with gcc:
gcc -o hello.out hello.s -no-pie
./hello.out
or with clang:
clang -o hello.out hello.s -no-pie
./hello.out
hello.s uses the GNU GAS format, which clang is highly compatible with, so both should work in general.
Read the full article