diff --git a/src/CodeGen/compilation/assign.rs b/src/CodeGen/compilation/assign.rs
index 5db4d106..327b3e29 100644
--- a/src/CodeGen/compilation/assign.rs
+++ b/src/CodeGen/compilation/assign.rs
@@ -44,7 +44,7 @@ impl CompilationHelper {
         let mut instr = MachineInstr::new(MachineMnemonic::Move);
 
         match location {
-            VarLocation::Reg(reg) => instr.add_operand(MachineOperand::Reg(reg)),
+            VarLocation::Reg(reg) => instr.set_out(MachineOperand::Reg(reg)),
         }
 
         match src1 {
@@ -69,7 +69,7 @@ impl CompilationHelper {
         );
 
         match location {
-            VarLocation::Reg(reg) => instr.add_operand(MachineOperand::Reg(reg)),
+            VarLocation::Reg(reg) => instr.set_out(MachineOperand::Reg(reg)),
         }
 
         mc_sink.push( instr );
diff --git a/src/CodeGen/compilation/call.rs b/src/CodeGen/compilation/call.rs
index 3af55725..125cf1e8 100644
--- a/src/CodeGen/compilation/call.rs
+++ b/src/CodeGen/compilation/call.rs
@@ -1,11 +1,60 @@
-use crate::prelude::Call;
+use crate::{prelude::{Call, Ir}, CodeGen::{MachineMnemonic, MachineOperand}};
 use crate::IR::{Block, Function, Var};
-use super::CompilationHelper;
+use super::{CompilationHelper, VarLocation};
 use crate::CodeGen::MachineInstr;
 
 impl CompilationHelper {
     #[allow(missing_docs)]
     pub fn compile_call(&mut self, node: &Call<Function, Vec<Var>, Var>, mc_sink: &mut Vec<MachineInstr>, block: &Block) {
-        todo!()
+        let boxed: Box<dyn Ir> = Box::new(node.clone());
+
+        let mut reg_args = 0;
+
+        let args = self.call.args(self.arch);
+
+        for arg in &node.inner2 {
+            let mut instr = MachineInstr::new(MachineMnemonic::Move);
+
+            
+            let arg_reg = args.get(reg_args);
+
+            if let Some(arg) = arg_reg {
+                instr.set_out(MachineOperand::Reg(*arg));
+            } else {
+                todo!("implemt arguments which are passed over the stack");
+            }
+
+            let src = self.vars.get(arg).expect("expected valid variable");
+
+            match src {
+                VarLocation::Reg(reg) => instr.add_operand(MachineOperand::Reg(*reg)),
+            }
+
+            mc_sink.push( instr );
+
+            reg_args += 1;
+        }
+
+        mc_sink.push(MachineInstr::new(
+            MachineMnemonic::Call(node.inner1.name.to_string())
+        ));
+
+        if block.isVarUsedAfterNode(&boxed, &node.inner3) {
+            let mut instr = MachineInstr::new(MachineMnemonic::Move);
+
+            let loc = self.alloc(&node.inner3);
+
+            instr.add_operand(
+                MachineOperand::Reg(
+                    self.call.return_reg(self.arch, node.inner1.ty.ret)
+                )
+            );
+
+            match loc {
+                VarLocation::Reg(reg) => instr.set_out(MachineOperand::Reg(reg)),
+            }
+
+            mc_sink.push(instr);
+        }
     }
 }
\ No newline at end of file
diff --git a/src/CodeGen/compilation/cast.rs b/src/CodeGen/compilation/cast.rs
index 752b70e3..3b9f48b3 100644
--- a/src/CodeGen/compilation/cast.rs
+++ b/src/CodeGen/compilation/cast.rs
@@ -1,10 +1,46 @@
-use crate::prelude::Cast;
+use crate::prelude::{Cast, Ir};
 use crate::IR::{Block, TypeMetadata, Var};
-use super::CompilationHelper;
-use crate::CodeGen::MachineInstr;
+use super::{CompilationHelper, VarLocation};
+use crate::CodeGen::{MachineInstr, MachineMnemonic, MachineOperand};
 
 impl CompilationHelper {
+    #[allow(missing_docs)]
     pub fn compile_cast(&mut self, node: &Cast<Var, TypeMetadata, Var>, mc_sink: &mut Vec<MachineInstr>, block: &Block) {
-        todo!()
+        let src1 = *self.vars.get(&node.inner1).expect("expected valid variable");
+
+        let boxed: Box<dyn Ir> = Box::new(node.clone());
+
+        if !block.isVarUsedAfterNode(&boxed, &node.inner1) {
+            self.free(&node.inner1)
+        }
+        if !block.isVarUsedAfterNode(&boxed, &node.inner3) {
+            return;
+        }
+
+        let out = self.alloc(&node.inner3);
+
+        let op = {
+
+        if node.inner1.ty.bitSize() > node.inner2.bitSize() {
+            MachineMnemonic::Zext
+        } else if node.inner1.ty.bitSize() < node.inner2.bitSize(){
+            MachineMnemonic::Downcast
+        } else {
+            return;
+        }
+        
+        };
+
+        let mut instr = MachineInstr::new(op);
+
+        match src1 {
+            VarLocation::Reg(reg) => instr.add_operand(MachineOperand::Reg(reg)),
+        }
+
+        match out {
+            VarLocation::Reg(reg) => instr.set_out(MachineOperand::Reg(reg)),
+        }
+
+        mc_sink.push(instr);
     }
 }
\ No newline at end of file
diff --git a/src/CodeGen/compilation/mod.rs b/src/CodeGen/compilation/mod.rs
index 6eaf5938..f04e035d 100644
--- a/src/CodeGen/compilation/mod.rs
+++ b/src/CodeGen/compilation/mod.rs
@@ -46,7 +46,7 @@ impl CompilationHelper {
         let location = if let Some(reg) = self.regs.pop(self.arch) {
             VarLocation::Reg(reg)
         } else {
-            todo!()
+            todo!("Registers ran out. And memory variables are currently not implemented")
         };
 
         self.vars.insert(var.clone(), location);
diff --git a/src/CodeGen/instr.rs b/src/CodeGen/instr.rs
index 4331e0ef..8c761424 100644
--- a/src/CodeGen/instr.rs
+++ b/src/CodeGen/instr.rs
@@ -57,7 +57,10 @@ pub enum MachineMnemonic {
     Sub,
     Xor,
 
-    Call,
+    Zext,
+    Downcast,
+
+    Call(String),
     Return,
 
     AdressLoad(String),
diff --git a/src/CodeGen/reg_vec.rs b/src/CodeGen/reg_vec.rs
index ecd5c3c9..6f9fa8b0 100644
--- a/src/CodeGen/reg_vec.rs
+++ b/src/CodeGen/reg_vec.rs
@@ -5,6 +5,7 @@ use super::reg::Reg;
 
 /// A register vector.
 /// Used for getting platform specific registers
+#[derive(Debug, Clone, PartialEq, Eq)]
 pub struct RegVec {
     regs: HashMap<Arch, Vec<Reg>>,
 }
@@ -21,6 +22,8 @@ impl RegVec {
     pub fn push(&mut self, arch: Arch, reg: Reg) {
         if let Some(entry) = self.regs.get_mut(&arch) {
             entry.push(reg);
+        } else {
+            self.regs.insert(arch, vec![reg]);
         }
     }
 
diff --git a/src/Target/x64/compilation.rs b/src/Target/x64/compilation.rs
index 304e93eb..bc4659e2 100644
--- a/src/Target/x64/compilation.rs
+++ b/src/Target/x64/compilation.rs
@@ -23,5 +23,7 @@ pub(crate) fn construct_compilation_helper(call_conv: CallConv) -> CompilationHe
     helper.regs.push(Arch::X86_64, Reg::x64(x64Reg::R14));
     helper.regs.push(Arch::X86_64, Reg::x64(x64Reg::R15));
 
+    helper.regs.reverse(Arch::X86_64);
+
     helper
 }
\ No newline at end of file