diff --git a/src/loader.rs b/src/loader.rs
index ab26d07..ff5ce88 100644
--- a/src/loader.rs
+++ b/src/loader.rs
@@ -30,6 +30,7 @@ pub fn parse_inst (buf: [u8; 4]) -> Option <Inst>
 		0x0b => Inst::GetTabUp (a, b, c),
 		0x0d => Inst::GetI (a, b, c),
 		0x22 => Inst::Add (a, b, c),
+		0x24 => Inst::Mul (a, b, c),
 		0x2e => Inst::MmBin (a, b, c),
 		0x3c => Inst::EqK (a, b, c),
 		0x38 => Inst::Jmp (s_j),
@@ -207,8 +208,10 @@ mod tests {
 	#[test]
 	fn parse_header () {
 		for (input, expected) in [
-			// Bytes 0 and 1 are line and column for debugging
-			// Byte 4 is slot count
+			// Bytes 0 and 1 are first line and last line for debugging
+			// Byte 2 is numparams
+			// Byte 3 is is_vararg
+			// Byte 4 is slot count / max stack size
 			// Byte 5 is instruction count
 			
 			([0x80, 0x80, 0x00, 0x01, 0x04, 0x92], (18,)),
diff --git a/src/state.rs b/src/state.rs
index 8d831ea..3b98641 100644
--- a/src/state.rs
+++ b/src/state.rs
@@ -487,7 +487,7 @@ impl State {
 					}
 					else {
 						// Return from the entire program
-						return self.registers [a..(a + b + c - 1)].to_vec();
+						return self.registers [a..(a + b - 1)].to_vec();
 					}
 				},
 				Instruction::Return1 (a) => {
diff --git a/src/tests.rs b/src/tests.rs
index 187ea6f..7371af3 100644
--- a/src/tests.rs
+++ b/src/tests.rs
@@ -157,6 +157,7 @@ fn fma () {
 	let bytecode = include_bytes! ("../test_vectors/fma.luac");
 	let mut rdr = std::io::Cursor::new (bytecode);
 	let file = crate::loader::parse_chunk (&mut rdr).unwrap ();
+	assert_eq! (file.blocks.len (), 4);
 	
 	for (arg, expected) in [
 		(vec! ["_exe_name"], vec! [122.into ()]),
diff --git a/test_vectors/bools.luac b/test_vectors/bools.luac
new file mode 100644
index 0000000..b63d506
Binary files /dev/null and b/test_vectors/bools.luac differ
diff --git a/test_vectors/closure.lua b/test_vectors/closure.lua
index 8e4250c..d15dfb3 100644
--- a/test_vectors/closure.lua
+++ b/test_vectors/closure.lua
@@ -6,4 +6,6 @@ local function make_closure (x)
 end
 
 local f = make_closure (11)
-print (f (12))
+local x = f (12)
+print (x)
+return x
diff --git a/test_vectors/closure.luac b/test_vectors/closure.luac
index b9ae82c..da75907 100644
Binary files a/test_vectors/closure.luac and b/test_vectors/closure.luac differ
diff --git a/test_vectors/fma.lua b/test_vectors/fma.lua
index 7525a54..f807eef 100644
--- a/test_vectors/fma.lua
+++ b/test_vectors/fma.lua
@@ -1,15 +1,15 @@
-local function add (a, b)
-	return a + b
+local function add (aa, bb)
+	return aa + bb
 end
 
-local function mul (a, b)
-	return a * b
+local function mul (cc, dd)
+	return cc * dd
 end
 
-local function fma (a, b, c)
-	return add (mul (a, b), c)
+local function fma (ee, ff, gg)
+	return add (mul (ee, ff), gg)
 end
 
-local x = fma (10, 11, 12)
-print (x)
-return x
+local hh = fma (10, 11, 12)
+print (hh)
+return hh
diff --git a/test_vectors/fma.luac b/test_vectors/fma.luac
new file mode 100644
index 0000000..e36b422
Binary files /dev/null and b/test_vectors/fma.luac differ