Move the cli into it’s own library

lib/cli/src/compilers/llvm.rs

@@ -0,0 +1,42 @@
+
+#[derive(Debug, StructOpt, Clone)]
+/// LLVM backend flags.
+pub struct LLVMCLIOptions {
+    /// Emit LLVM IR before optimization pipeline.
+    #[structopt(long = "llvm-pre-opt-ir", parse(from_os_str))]
+    pre_opt_ir: Option<PathBuf>,
+
+    /// Emit LLVM IR after optimization pipeline.
+    #[structopt(long = "llvm-post-opt-ir", parse(from_os_str))]
+    post_opt_ir: Option<PathBuf>,
+
+    /// Emit LLVM generated native code object file.
+    #[structopt(long = "llvm-object-file", parse(from_os_str))]
+    obj_file: Option<PathBuf>,
+}
+
+
+impl LLVMCallbacks for LLVMCLIOptions {
+    fn preopt_ir_callback(&mut self, module: &InkwellModule) {
+        if let Some(filename) = &self.pre_opt_ir {
+            module.print_to_file(filename).unwrap();
+        }
+    }
+
+    fn postopt_ir_callback(&mut self, module: &InkwellModule) {
+        if let Some(filename) = &self.post_opt_ir {
+            module.print_to_file(filename).unwrap();
+        }
+    }
+
+    fn obj_memory_buffer_callback(&mut self, memory_buffer: &InkwellMemoryBuffer) {
+        if let Some(filename) = &self.obj_file {
+            let mem_buf_slice = memory_buffer.as_slice();
+            let mut file = fs::File::create(filename).unwrap();
+            let mut pos = 0;
+            while pos < mem_buf_slice.len() {
+                pos += file.write(&mem_buf_slice[pos..]).unwrap();
+            }
+        }
+    }
+}