diff --git a/src/main.c b/src/main.c
index a38fe34..cc02b04 100644
--- a/src/main.c
+++ b/src/main.c
@@ -30,7 +30,9 @@ int main(int argc, char **argv) {
   vm.return_stack_size = STACK_SIZE;
   vm.stack_size = STACK_SIZE;
   vm.memory_size = MEMORY_SIZE;
-  test_recursive_function_compile(vm.memory);
+  test_loop_compile(vm.memory);
+  /* test_add_function_compile(vm.memory); */
+  /* test_recursive_function_compile(vm.memory); */
 
 #ifdef __EMSCRIPTEN__
   emscripten_set_main_loop(mainloop, 0, 1);
diff --git a/src/test.c b/src/test.c
index 17aecb2..c2dd4b3 100644
--- a/src/test.c
+++ b/src/test.c
@@ -30,7 +30,7 @@ uint32_t test_loop_compile(Value *memory) {
   memory[i++].f = 5.0f;
   memory[i++].u = OP(OP_ADD_REAL, 0, 0, 5); /* a += 5.0; */
   memory[i++].u = OP(OP_ADD_INT, 1, 1, 3);  /* (implied by loop) i = i + (-1) */
-  memory[i++].u = OP(OP_JGT_INT, 4, 1, 2);  /* } */
+  memory[i++].u = OP(OP_JGE_INT, 4, 1, 2);  /* } */
   memory[i++].u = OP(OP_REAL_TO_UINT, 1, 0, 0); /* let b = a as nat; */
   memory[i++].u = OP(OP_READ_STRING, 2, 0, 0);  /* let user_string = gets(); */
   memory[i++].u = OP(OP_UINT_TO_STRING, 3, 1, 0);
diff --git a/src/vm.c b/src/vm.c
index d3f4fe6..da3da81 100644
--- a/src/vm.c
+++ b/src/vm.c
@@ -81,9 +81,7 @@ bool step_vm(VM *vm) {
     return true;
   case OP_RETURN:
     vm->pc = vm->return_stack[--vm->rp].u;  /* set pc to return address */
-    Slice s = vm->frames[vm->fp].allocated; /* get allocated slice */
-    vm->fp--;                                      /* pop the frame */
-    vm->mp = s.start; /* reset memory pointer to start of old slice */
+    vm->mp = vm->frames[vm->fp--].allocated.start; /* reset memory pointer to start of old slice, pop the frame */
     return true;
   case OP_LOADI:
     vm->frames[vm->fp].registers[dest].i = vm->memory[vm->pc++].i;
diff --git a/test/bench/add.lua b/test/bench/add.lua
new file mode 100644
index 0000000..e9977da
--- /dev/null
+++ b/test/bench/add.lua
@@ -0,0 +1,6 @@
+function add(a, b)
+  return a + b
+end
+
+local sum = add(1, 1)
+print(tostring(sum))
diff --git a/test/bench/add.pl b/test/bench/add.pl
new file mode 100644
index 0000000..65985eb
--- /dev/null
+++ b/test/bench/add.pl
@@ -0,0 +1,7 @@
+sub add {
+  my ($a, $b) = @_;
+  return $a + $b;
+}
+
+my $sum = add(1, 1);
+print($sum . "\n");
diff --git a/test/bench/add.py b/test/bench/add.py
new file mode 100644
index 0000000..d8f7edb
--- /dev/null
+++ b/test/bench/add.py
@@ -0,0 +1,5 @@
+def add(a, b):
+  return a + b
+
+sum = add(1, 1)
+print(str(sum))
diff --git a/test/bench/add.wren b/test/bench/add.wren
new file mode 100644
index 0000000..fbaca81
--- /dev/null
+++ b/test/bench/add.wren
@@ -0,0 +1,6 @@
+var add = Fn.new { |a, b|
+  return a + b
+}
+
+var sum = add.call(1, 1)
+System.print(sum.toString)
diff --git a/test/bench/loop.lua b/test/bench/loop.lua
new file mode 100644
index 0000000..e73282f
--- /dev/null
+++ b/test/bench/loop.lua
@@ -0,0 +1,10 @@
+local a = 5.0
+for i = 5, 0, -1 do
+  a = a + 5.0
+end
+local b = math.floor(a)
+io.write("Enter a string: ")
+local user_string = io.read("*l")
+print(tostring(a))
+print(tostring(b))
+print(user_string)
diff --git a/test/bench/loop.pl b/test/bench/loop.pl
new file mode 100644
index 0000000..9427079
--- /dev/null
+++ b/test/bench/loop.pl
@@ -0,0 +1,11 @@
+my $a = 5.0;
+for (my $i = 5; $i >= 0; $i--) {
+  $a += 5.0;
+}
+my $b = int($a);
+print "Enter a string: ";
+my $user_string = <STDIN>;
+chomp($user_string);
+print($a . "\n");
+print($b . "\n");
+print($user_string . "\n");
diff --git a/test/bench/loop.py b/test/bench/loop.py
new file mode 100644
index 0000000..00a0d6a
--- /dev/null
+++ b/test/bench/loop.py
@@ -0,0 +1,8 @@
+a = 5.0
+for i in range(5, -1, -1):
+  a += 5.0
+b = int(a)
+user_string = input("Enter a string: ")
+print(str(a))
+print(str(b))
+print(user_string)
diff --git a/test/bench/loop.wren b/test/bench/loop.wren
new file mode 100644
index 0000000..beca453
--- /dev/null
+++ b/test/bench/loop.wren
@@ -0,0 +1,10 @@
+var a = 5.0
+var i = 5
+while (i >= 0) {
+  a = a + 5.0
+  i = i - 1
+}
+var b = a
+System.write("Enter a string: ")
+System.print(a.toString)
+System.print(b.toString)
diff --git a/test/bench/run.sh b/test/bench/run.sh
index cc6d61b..f71b44d 100755
--- a/test/bench/run.sh
+++ b/test/bench/run.sh
@@ -3,27 +3,35 @@
 # Exit on error
 set -e
 
+# Check if a filename was provided
+if [ "$#" -ne 1 ]; then
+    echo "Usage: $0 <filename_without_extension>"
+    exit 1
+fi
+
+FILENAME=$1
+
 # Function to print section headers
 print_section() {
   printf '\n\e[1;34m%s\e[0m\n' "$1"
 }
 
+# Wren Implementation
+print_section "Wren ($FILENAME.wren)"
+time wren "$FILENAME.wren"
+
 # Lua Implementation
-print_section "Lua (fib.lua)"
-time lua fib.lua
+print_section "Lua ($FILENAME.lua)"
+time lua "$FILENAME.lua"
 
 # Perl Implementation
-print_section "Perl (fib.pl)"
-time perl fib.pl
+print_section "Perl ($FILENAME.pl)"
+time perl "$FILENAME.pl"
 
 # Python Implementation
-print_section "Python (fib.py)"
-time python3 fib.py
-
-# Wren Implementation
-print_section "Wren (fib.wren)"
-time wren fib.wren
+print_section "Python ($FILENAME.py)"
+time python3 "$FILENAME.py"
 
 # ZRE Implementation
-print_section "zre (fib.zre)"
-time ../../src/zre #currently hardcoded
+print_section "zre ($FILENAME.zre)"
+time ../../src/zre "$FILENAME.zre"
diff --git a/test/fib.s b/test/fib.s
index d0895bf..335d7a9 100644
--- a/test/fib.s
+++ b/test/fib.s
@@ -1,5 +1,5 @@
 main:
-	loadi $0 23
+	loadi $0 35
 	pushi $0
 	call &fib
 	popi $0
diff --git a/test/loop.zre b/test/loop.zre
index 7647722..d1979e3 100644
--- a/test/loop.zre
+++ b/test/loop.zre
@@ -1,9 +1,9 @@
-real a = 5.0;
-do (int i = 5, 0, -1) {
+let a = 5.0;
+do (let i = 5, 0, -1) {
   a += 5.0;
 }
-nat b = a as nat;
-str user_string = readln();
+let b = a as nat;
+let user_string = gets();
 print(a.toS());
 print(b.toS());
 print(user_string);