diff --git a/dcb-exe/src/exe.rs b/dcb-exe/src/exe.rs
index 66e9a6b..d8094f9 100644
--- a/dcb-exe/src/exe.rs
+++ b/dcb-exe/src/exe.rs
@@ -76,7 +76,7 @@ impl Exe {
 
 	/// Returns this executable's instruction range
 	#[must_use]
-	pub fn inst_range(&self) -> Range<Pos> {
+	pub fn insts_range(&self) -> Range<Pos> {
 		let start = self.header.start_pos;
 		let end = self.header.start_pos + self.header.size;
 		start..end
@@ -107,6 +107,13 @@ impl Exe {
 		file.read_exact(&mut header_bytes).map_err(DeserializeError::ReadHeader)?;
 		let header = Header::from_bytes(&header_bytes).map_err(DeserializeError::ParseHeader)?;
 
+		// Get the instruction range
+		let insts_range = {
+			let start = header.start_pos;
+			let end = header.start_pos + header.size;
+			start..end
+		};
+
 		// Read all of the bytes
 		let mut bytes = vec![0u8; usize::try_from(header.size).expect("Len didn't fit into `usize`")].into_boxed_slice();
 		file.read_exact(bytes.as_mut()).map_err(DeserializeError::ReadData)?;
@@ -119,9 +126,9 @@ impl Exe {
 		let insts = inst::ParseIter::new(&*bytes, header.start_pos);
 
 		// Then parse all heuristic tables
-		let heuristics_data_table = DataTable::search_instructions(insts.clone());
+		let heuristics_data_table = DataTable::search_instructions(insts_range.clone(), insts.clone());
 		let data_table = known_data_table.merge_with(heuristics_data_table);
-		let heuristics_func_table = FuncTable::search_instructions(insts);
+		let heuristics_func_table = FuncTable::search_instructions(insts_range, insts);
 		let func_table = known_func_table.merge_with(heuristics_func_table);
 
 		Ok(Self {
diff --git a/dcb-exe/src/exe/data/table.rs b/dcb-exe/src/exe/data/table.rs
index 4172c49..da18417 100644
--- a/dcb-exe/src/exe/data/table.rs
+++ b/dcb-exe/src/exe/data/table.rs
@@ -23,7 +23,12 @@ use crate::exe::{
 	Pos,
 };
 use dcb_util::DiscardingSortedMergeIter;
-use std::{collections::BTreeSet, fs::File, iter::FromIterator, ops::RangeBounds};
+use std::{
+	collections::BTreeSet,
+	fs::File,
+	iter::FromIterator,
+	ops::{Range, RangeBounds},
+};
 
 /// Data table
 ///
@@ -89,7 +94,7 @@ impl DataTable {
 	/// Searches all instructions for references to
 	/// executable data using certain heuristics.
 	#[must_use]
-	pub fn search_instructions<'a>(insts: impl Iterator<Item = (Pos, Inst<'a>)> + Clone) -> Self {
+	pub fn search_instructions<'a>(_insts_range: Range<Pos>, insts: impl Iterator<Item = (Pos, Inst<'a>)> + Clone) -> Self {
 		// Get all possible references to data
 		let references: BTreeSet<Pos> = insts
 			.clone()
diff --git a/dcb-exe/src/exe/func/table.rs b/dcb-exe/src/exe/func/table.rs
index 7e18d2b..0d39eaa 100644
--- a/dcb-exe/src/exe/func/table.rs
+++ b/dcb-exe/src/exe/func/table.rs
@@ -27,7 +27,7 @@ use std::{
 	collections::{BTreeMap, BTreeSet},
 	fs::File,
 	iter::FromIterator,
-	ops::RangeBounds,
+	ops::{Range, RangeBounds},
 };
 
 /// Function table
@@ -97,7 +97,7 @@ impl FuncTable {
 	/// Creates a new list of functions from an iterator over insts
 	#[must_use]
 	#[allow(clippy::too_many_lines)] // TODO: Refactor?
-	pub fn search_instructions<'a>(insts: impl Iterator<Item = (Pos, Inst<'a>)> + Clone) -> Self {
+	pub fn search_instructions<'a>(insts_range: Range<Pos>, insts: impl Iterator<Item = (Pos, Inst<'a>)> + Clone) -> Self {
 		// Get all returns
 		let returns: BTreeSet<Pos> = insts
 			.clone()
@@ -146,7 +146,7 @@ impl FuncTable {
 				Inst::Basic(basic::Inst::Cond(inst)) => Some(inst.target(pos)),
 				_ => None,
 			})
-			//.filter(|target| Inst::CODE_RANGE.contains(target))
+			.filter(|target| insts_range.contains(target))
 			.collect();
 
 		// Now check every `Jal` and `Dw` for possible function entrances
@@ -163,7 +163,7 @@ impl FuncTable {
 				Inst::Directive(Directive::Dw(address)) => Some(Pos(address)),
 				_ => None,
 			})
-			//.filter(|target| Inst::CODE_RANGE.contains(target))
+			.filter(|target| insts_range.contains(target))
 			.collect();
 
 		#[allow(clippy::cognitive_complexity)] // TODO: Fix
diff --git a/dcb-exe/src/exe/iter.rs b/dcb-exe/src/exe/iter.rs
index 45355c3..faa3555 100644
--- a/dcb-exe/src/exe/iter.rs
+++ b/dcb-exe/src/exe/iter.rs
@@ -58,7 +58,7 @@ impl<'a> Iterator for Iter<'a> {
 	fn next(&mut self) -> Option<Self::Item> {
 		// If we're at the end, return `None`
 		let cur_pos = self.cur_pos;
-		if cur_pos >= self.exe.inst_range().end {
+		if cur_pos >= self.exe.insts_range().end {
 			return None;
 		}
 
@@ -100,11 +100,11 @@ impl<'a> Iterator for Iter<'a> {
 			},
 			(Some(next_data), None) => next_data.pos,
 			(None, Some(next_func)) => next_func.start_pos,
-			(None, None) => self.exe.inst_range().end,
+			(None, None) => self.exe.insts_range().end,
 		};
 
 		// Make sure to limit the end position
-		let end_pos = end_pos.min(self.exe.inst_range().end);
+		let end_pos = end_pos.min(self.exe.insts_range().end);
 		self.cur_pos = end_pos;