Update README

README.md

@@ -9,15 +9,16 @@ VitaminC 🍋 is an educational C compiler frontend written in C++. As a fronten
 > [!WARNING]
 > This project is still under development. Many features are not yet implemented. Currently, we do not support preprocessor directives, and only the `int` type and its pointer, as well as object types, are supported.
 
-The main goal of this project is to demonstrate how a compiler frontend works with [the LLVM compiler infrastructure](https://llvm.org/) and generates LLVM IR. However, we are not yet there. Currently, we generate [QBE](https://c9x.me/compile/) IR manually.
+The main goal of this project is to demonstrate how a compiler frontend works with [the LLVM compiler infrastructure](https://llvm.org/) and generates LLVM IR. Currently, this compiler can generate [QBE](https://c9x.me/compile/) IR and [LLVM](https://llvm.org/docs/LangRef.html) IR.
 
 We are not aiming to be a fully compliant C compiler, although we strive to be as compliant as possible with C89 and support common C99 features.
 
 ## Prerequisites
 
 - A C++ compiler that supports C++17.
 - [GNU Make](https://www.gnu.org/software/make/): for building the project.
-- [QBE](https://c9x.me/compile/releases.html): for compiling the QBE IR down to assembly.
+- [QBE](https://c9x.me/compile/releases.html): for compiling QBE IR to assembly.
+- [LLVM-18](https://releases.llvm.org/): for generating LLVM IR and compiling it to assembly.
 - [cxxopts](https://github.com/jarro2783/cxxopts): for command-line argument parsing.
 - [fmt](https://fmt.dev/latest/index.html): for modern C++ formatting.
 - (test-only) [turnt](https://github.com/cucapra/turnt): for snapshot testing.
@@ -49,10 +50,10 @@ A simple C compiler.
 Usage:
   ./vitaminc [options] file
 
-  -o, --output <file>  Write output to <file> (default: a.out)
-  -d, --dump           Dump the abstract syntax tree
-  -t, --target [qbe]   Specify target IR (default: qbe)
-  -h, --help           Display available options
+  -o, --output <file>      Write output to <file> (default: a.out)
+  -d, --dump               Dump the abstract syntax tree
+  -t, --target [qbe|llvm]  Specify target IR (default: qbe)
+  -h, --help               Display available options
 ```
 
 ## License