diff --git a/dcb-exe/src/exe/inst.rs b/dcb-exe/src/exe/inst.rs
index 8a9d78e..b251dd9 100644
--- a/dcb-exe/src/exe/inst.rs
+++ b/dcb-exe/src/exe/inst.rs
@@ -106,14 +106,6 @@ impl<'a> InstSize for Inst<'a> {
 }
 
 impl<'a> InstFmt for Inst<'a> {
-	fn mnemonic(&self) -> &'static str {
-		match self {
-			Self::Basic(inst) => inst.mnemonic(),
-			Self::Pseudo(inst) => inst.mnemonic(),
-			Self::Directive(directive) => directive.mnemonic(),
-		}
-	}
-
 	fn fmt(&self, pos: Pos, f: &mut std::fmt::Formatter) -> std::fmt::Result {
 		match self {
 			Self::Basic(inst) => inst.fmt(pos, f),
diff --git a/dcb-exe/src/exe/inst/basic.rs b/dcb-exe/src/exe/inst/basic.rs
index 2b6bbaf..1bbac63 100644
--- a/dcb-exe/src/exe/inst/basic.rs
+++ b/dcb-exe/src/exe/inst/basic.rs
@@ -6,6 +6,7 @@
 
 // Modules
 pub mod alu;
+pub mod co;
 pub mod cond;
 pub mod jmp;
 pub mod load;
@@ -48,6 +49,9 @@ pub enum Raw {
 
 	/// Syscall
 	Sys(sys::Raw),
+
+	/// Co-processor
+	Co(u32),
 }
 
 impl Raw {
@@ -57,8 +61,7 @@ impl Raw {
 	#[allow(clippy::many_single_char_names)] // `bitmatch` can only output single character names.
 	pub fn from_u32(raw: u32) -> Option<Self> {
 		#[rustfmt::skip]
-		let raw = #[bitmatch]
-		match raw {
+		let raw = #[bitmatch] match raw {
 			"000000_?????_ttttt_ddddd_iiiii_0000ff" => Self::Shift(shift::Raw::Imm(shift::imm::Raw {       t, d, i, f })),
 			"000000_sssss_ttttt_ddddd_?????_0001ff" => Self::Shift(shift::Raw::Reg(shift::reg::Raw {    s, t, d,    f })),
 			"000000_sssss_?????_ddddd_?????_00100f" => Self::Jmp  (jmp  ::Raw::Reg(jmp  ::reg::Raw {    s,    d,    f })),
@@ -71,18 +74,7 @@ impl Raw {
 			"001ppp_sssss_ttttt_iiiii_iiiii_iiiiii" => Self::Alu  (alu  ::Raw::Imm(alu  ::imm::Raw { p, s, t,    i    })),
 			"100ppp_sssss_ttttt_iiiii_iiiii_iiiiii" => Self::Load (                load ::     Raw { p, s, t,    i    } ),
 			"101ppp_sssss_ttttt_iiiii_iiiii_iiiiii" => Self::Store(                store::     Raw { p, s, t,    i    } ),
-
-			/*
-			"0100nn_1iiii_iiiii_iiiii_iiiii_iiiiii" => CopN { n: n.truncate(), imm: i},
-			"0100nn_00000_ttttt_ddddd_?????_000000" => MfcN { n: n.truncate(), rt: reg(t)?, rd: reg(d)? },
-			"0100nn_00010_ttttt_ddddd_?????_000000" => CfcN { n: n.truncate(), rt: reg(t)?, rd: reg(d)? },
-			"0100nn_00100_ttttt_ddddd_?????_000000" => MtcN { n: n.truncate(), rt: reg(t)?, rd: reg(d)? },
-			"0100nn_00110_ttttt_ddddd_?????_000000" => CtcN { n: n.truncate(), rt: reg(t)?, rd: reg(d)? },
-			"0100nn_01000_00000_iiiii_iiiii_iiiiii" => BcNf { n: n.truncate(), target: i.truncate() },
-			"0100nn_01000_00001_iiiii_iiiii_iiiiii" => BcNt { n: n.truncate(), target: i.truncate() },
-			"1100nn_sssss_ttttt_iiiii_iiiii_iiiiii" => LwcN { n: n.truncate(), rs: reg(s)?, rt: reg(t)?, imm: i.truncate() },
-			"1110nn_sssss_ttttt_iiiii_iiiii_iiiiii" => SwcN { n: n.truncate(), rs: reg(s)?, rt: reg(t)?, imm: i.truncate() },
-			*/
+			"?1????_?????_?????_?????_?????_??????" => Self::Co   (raw),
 			_ => return None,
 		};
 
@@ -107,6 +99,7 @@ impl Raw {
 			Self::Alu  (alu  ::Raw::Imm(alu  ::imm::Raw { p, s, t,    i    })) => bitpack!("001ppp_sssss_ttttt_iiiii_iiiii_iiiiii"),
 			Self::Load (                load ::     Raw { p, s, t,    i    } ) => bitpack!("100ppp_sssss_ttttt_iiiii_iiiii_iiiiii"),
 			Self::Store(                store::     Raw { p, s, t,    i    } ) => bitpack!("101ppp_sssss_ttttt_iiiii_iiiii_iiiiii"),
+			Self::Co   (raw) => raw,
 		}
 	}
 }
@@ -142,6 +135,9 @@ pub enum Inst {
 
 	/// Syscall
 	Sys(sys::Inst),
+
+	/// Co-processor
+	Co(co::Inst),
 }
 
 
@@ -161,6 +157,7 @@ impl Decodable for Inst {
 			Raw::Shift(raw) => Self::Shift(shift::Inst::decode(raw)?),
 			Raw::Store(raw) => Self::Store(store::Inst::decode(raw)?),
 			Raw::Sys  (raw) => Self::Sys  (sys  ::Inst::decode(raw)?),
+			Raw::Co   (raw) => Self::Co   (co   ::Inst::decode(raw)?),
 		};
 
 		Some(inst)
@@ -180,6 +177,7 @@ impl Encodable for Inst {
 			Self::Shift(inst) => Raw::Shift(inst.encode()),
 			Self::Store(inst) => Raw::Store(inst.encode()),
 			Self::Sys  (inst) => Raw::Sys  (inst.encode()),
+			Self::Co   (inst) => Raw::Co   (inst.encode()),
 		}
 	}
 }
@@ -192,21 +190,6 @@ impl<T: Decodable> InstSize for T {
 }
 
 impl InstFmt for Inst {
-	#[rustfmt::skip]
-	fn mnemonic(&self) -> &'static str {
-		match self {
-			Self::Alu  (inst) => inst.mnemonic(),
-			Self::Cond (inst) => inst.mnemonic(),
-			Self::Jmp  (inst) => inst.mnemonic(),
-			Self::Load (inst) => inst.mnemonic(),
-			Self::Lui  (inst) => inst.mnemonic(),
-			Self::Mult (inst) => inst.mnemonic(),
-			Self::Shift(inst) => inst.mnemonic(),
-			Self::Store(inst) => inst.mnemonic(),
-			Self::Sys  (inst) => inst.mnemonic(),
-		}
-	}
-
 	#[rustfmt::skip]
 	fn fmt(&self, pos: crate::Pos, f: &mut std::fmt::Formatter) -> std::fmt::Result {
 		match self {
@@ -219,6 +202,7 @@ impl InstFmt for Inst {
 			Self::Shift(inst) => inst.fmt(pos, f),
 			Self::Store(inst) => inst.fmt(pos, f),
 			Self::Sys  (inst) => inst.fmt(pos, f),
+			Self::Co   (inst) => inst.fmt(pos, f),
 		}
 	}
 }
diff --git a/dcb-exe/src/exe/inst/basic/alu.rs b/dcb-exe/src/exe/inst/basic/alu.rs
index f93239c..80b08aa 100644
--- a/dcb-exe/src/exe/inst/basic/alu.rs
+++ b/dcb-exe/src/exe/inst/basic/alu.rs
@@ -53,13 +53,6 @@ impl Encodable for Inst {
 }
 
 impl InstFmt for Inst {
-	fn mnemonic(&self) -> &'static str {
-		match self {
-			Self::Imm(inst) => inst.mnemonic(),
-			Self::Reg(inst) => inst.mnemonic(),
-		}
-	}
-
 	fn fmt(&self, pos: crate::Pos, f: &mut std::fmt::Formatter) -> std::fmt::Result {
 		match self {
 			Self::Imm(inst) => inst.fmt(pos, f),
diff --git a/dcb-exe/src/exe/inst/basic/alu/imm.rs b/dcb-exe/src/exe/inst/basic/alu/imm.rs
index 08b3cfa..1bb9bf8 100644
--- a/dcb-exe/src/exe/inst/basic/alu/imm.rs
+++ b/dcb-exe/src/exe/inst/basic/alu/imm.rs
@@ -134,10 +134,6 @@ impl Encodable for Inst {
 }
 
 impl InstFmt for Inst {
-	fn mnemonic(&self) -> &'static str {
-		self.kind.mnemonic()
-	}
-
 	fn fmt(&self, _pos: crate::Pos, f: &mut std::fmt::Formatter) -> std::fmt::Result {
 		let Self { dst, lhs, kind } = self;
 		let mnemonic = kind.mnemonic();
diff --git a/dcb-exe/src/exe/inst/basic/alu/reg.rs b/dcb-exe/src/exe/inst/basic/alu/reg.rs
index 92d78ad..93ee55c 100644
--- a/dcb-exe/src/exe/inst/basic/alu/reg.rs
+++ b/dcb-exe/src/exe/inst/basic/alu/reg.rs
@@ -141,13 +141,10 @@ impl Encodable for Inst {
 }
 
 impl InstFmt for Inst {
-	fn mnemonic(&self) -> &'static str {
-		self.kind.mnemonic()
-	}
-
 	fn fmt(&self, _pos: crate::Pos, f: &mut std::fmt::Formatter) -> std::fmt::Result {
 		let Self { dst, lhs, rhs, kind } = self;
+		let mnemonic = kind.mnemonic();
 
-		write!(f, "{} {dst}, {lhs}, {rhs}", kind.mnemonic())
+		write!(f, "{mnemonic} {dst}, {lhs}, {rhs}")
 	}
 }
diff --git a/dcb-exe/src/exe/inst/basic/co.rs b/dcb-exe/src/exe/inst/basic/co.rs
new file mode 100644
index 0000000..f4e6c97
--- /dev/null
+++ b/dcb-exe/src/exe/inst/basic/co.rs
@@ -0,0 +1,138 @@
+//! Co-processor instructions
+
+// Modules
+//pub mod exec;
+//pub mod move_reg;
+//pub mod cond;
+//pub mod load;
+//pub mod store;
+
+// Imports
+use crate::exe::inst::{
+	basic::{Decodable, Encodable},
+	InstFmt, Register,
+};
+use int_conv::{Signed, Truncated};
+
+/// Co-processor instruction kind
+#[derive(PartialEq, Eq, Clone, Copy, Debug)]
+pub enum Kind {
+	/// Execute
+	CopN {
+		/// Command to execute
+		imm: u32,
+	},
+
+	/// Move data register from co-processor
+	MfcN {
+		/// Destination
+		dst: Register,
+
+		/// Source
+		src: Register,
+	},
+
+	/// Move control register from co-processor
+	CfcN {
+		/// Destination
+		dst: Register,
+
+		/// Source
+		src: Register,
+	},
+	/// Move data register to co-processor
+	MtcN {
+		/// Destination
+		dst: Register,
+
+		/// Source
+		src: Register,
+	},
+	/// Move control register to co-processor
+	CtcN {
+		/// Destination
+		dst: Register,
+
+		/// Source
+		src: Register,
+	},
+	/// Branch if true
+	BcNf {
+		/// Offset
+		offset: i16,
+	},
+
+	/// Branch if false
+	BcNt {
+		/// Offset
+		offset: i16,
+	},
+
+	/// Load co-processor
+	LwcN {
+		/// Destination
+		dst: Register,
+
+		/// Source
+		src: Register,
+
+		/// offset
+		offset: i16,
+	},
+
+	/// Store co-processor
+	SwcN {
+		/// Destination
+		dst: Register,
+
+		/// Source
+		src: Register,
+
+		/// offset
+		offset: i16,
+	},
+}
+
+/// Store instructions
+#[derive(PartialEq, Eq, Clone, Copy, Debug)]
+pub struct Inst {
+	/// Co-processor number
+	pub n: u32,
+
+	/// Kind
+	pub kind: Kind,
+}
+
+impl Decodable for Inst {
+	type Raw = u32;
+
+	#[bitmatch::bitmatch]
+	fn decode(raw: Self::Raw) -> Option<Self> {
+		#[rustfmt::skip]
+		let (n, kind) = #[bitmatch] match raw {
+			"0100nn_1iiii_iiiii_iiiii_iiiii_iiiiii" => (n, Kind::CopN { imm: i }),
+			"0100nn_00000_ttttt_ddddd_?????_000000" => (n, Kind::MfcN { dst: Register::new(t)?, src: Register::new(d)? }),
+			"0100nn_00010_ttttt_ddddd_?????_000000" => (n, Kind::CfcN { dst: Register::new(t)?, src: Register::new(d)? }),
+			"0100nn_00100_ttttt_ddddd_?????_000000" => (n, Kind::MtcN { dst: Register::new(d)?, src: Register::new(t)? }),
+			"0100nn_00110_ttttt_ddddd_?????_000000" => (n, Kind::CtcN { dst: Register::new(d)?, src: Register::new(t)? }),
+			"0100nn_01000_00000_iiiii_iiiii_iiiiii" => (n, Kind::BcNf { offset: i.truncated::<u16>().as_signed() }),
+			"0100nn_01000_00001_iiiii_iiiii_iiiiii" => (n, Kind::BcNt { offset: i.truncated::<u16>().as_signed() }),
+			"1100nn_sssss_ttttt_iiiii_iiiii_iiiiii" => (n, Kind::LwcN { dst: Register::new(t)?, src: Register::new(s)?, offset: i.truncated::<u16>().as_signed() }),
+			"1110nn_sssss_ttttt_iiiii_iiiii_iiiiii" => (n, Kind::SwcN { dst: Register::new(s)?, src: Register::new(t)?, offset: i.truncated::<u16>().as_signed() }),
+			_ => return None,
+		};
+
+		Some(Self { n, kind })
+	}
+}
+impl Encodable for Inst {
+	fn encode(&self) -> Self::Raw {
+		todo!();
+	}
+}
+
+impl InstFmt for Inst {
+	fn fmt(&self, _pos: crate::Pos, _f: &mut std::fmt::Formatter) -> std::fmt::Result {
+		todo!();
+	}
+}
diff --git a/dcb-exe/src/exe/inst/basic/co/cond.rs b/dcb-exe/src/exe/inst/basic/co/cond.rs
new file mode 100644
index 0000000..e69de29
diff --git a/dcb-exe/src/exe/inst/basic/co/exec.rs b/dcb-exe/src/exe/inst/basic/co/exec.rs
new file mode 100644
index 0000000..06e7691
--- /dev/null
+++ b/dcb-exe/src/exe/inst/basic/co/exec.rs
@@ -0,0 +1,50 @@
+//! Co-processor exec instructions
+
+//! Lui instruction
+
+// Imports
+use crate::exe::inst::{
+	basic::{Decodable, Encodable},
+	InstFmt, Register,
+};
+use int_conv::{Truncated, ZeroExtended};
+
+/// Raw representation
+#[derive(PartialEq, Eq, Clone, Copy, Debug)]
+pub struct Raw {
+	/// Immediate
+	pub i: u32,
+}
+
+/// Exec co-processor.
+#[derive(PartialEq, Eq, Clone, Copy, Debug)]
+pub struct Inst {
+	/// Value
+	pub value: u32,
+}
+
+impl Decodable for Inst {
+	type Raw = Raw;
+
+	fn decode(raw: Self::Raw) -> Option<Self> {
+		Some(Self { value: raw.i })
+	}
+}
+impl Encodable for Inst {
+	fn encode(&self) -> Self::Raw {
+		Raw { i: self.value }
+	}
+}
+
+
+impl InstFmt for Inst {
+	fn mnemonic(&self) -> &'static str {
+		"cop"
+	}
+
+	fn fmt(&self, _pos: crate::Pos, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+		let Self { dst, value } = self;
+
+		write!(f, "lui {dst}, {value:#x}")
+	}
+}
diff --git a/dcb-exe/src/exe/inst/basic/co/load.rs b/dcb-exe/src/exe/inst/basic/co/load.rs
new file mode 100644
index 0000000..e69de29
diff --git a/dcb-exe/src/exe/inst/basic/co/move_reg.rs b/dcb-exe/src/exe/inst/basic/co/move_reg.rs
new file mode 100644
index 0000000..e69de29
diff --git a/dcb-exe/src/exe/inst/basic/co/store.rs b/dcb-exe/src/exe/inst/basic/co/store.rs
new file mode 100644
index 0000000..e69de29
diff --git a/dcb-exe/src/exe/inst/basic/cond.rs b/dcb-exe/src/exe/inst/basic/cond.rs
index ab66894..fe04f20 100644
--- a/dcb-exe/src/exe/inst/basic/cond.rs
+++ b/dcb-exe/src/exe/inst/basic/cond.rs
@@ -148,10 +148,6 @@ impl Encodable for Inst {
 }
 
 impl InstFmt for Inst {
-	fn mnemonic(&self) -> &'static str {
-		self.kind.mnemonic()
-	}
-
 	fn fmt(&self, pos: Pos, f: &mut fmt::Formatter) -> fmt::Result {
 		let Self { kind, arg, .. } = self;
 		let mnemonic = kind.mnemonic();
diff --git a/dcb-exe/src/exe/inst/basic/jmp.rs b/dcb-exe/src/exe/inst/basic/jmp.rs
index 1867928..51002c0 100644
--- a/dcb-exe/src/exe/inst/basic/jmp.rs
+++ b/dcb-exe/src/exe/inst/basic/jmp.rs
@@ -53,13 +53,6 @@ impl Encodable for Inst {
 }
 
 impl InstFmt for Inst {
-	fn mnemonic(&self) -> &'static str {
-		match self {
-			Self::Imm(inst) => inst.mnemonic(),
-			Self::Reg(inst) => inst.mnemonic(),
-		}
-	}
-
 	fn fmt(&self, pos: crate::Pos, f: &mut std::fmt::Formatter) -> std::fmt::Result {
 		match self {
 			Self::Imm(inst) => inst.fmt(pos, f),
diff --git a/dcb-exe/src/exe/inst/basic/jmp/imm.rs b/dcb-exe/src/exe/inst/basic/jmp/imm.rs
index 041c50a..f234be8 100644
--- a/dcb-exe/src/exe/inst/basic/jmp/imm.rs
+++ b/dcb-exe/src/exe/inst/basic/jmp/imm.rs
@@ -91,10 +91,6 @@ impl Encodable for Inst {
 }
 
 impl InstFmt for Inst {
-	fn mnemonic(&self) -> &'static str {
-		self.kind.mnemonic()
-	}
-
 	fn fmt(&self, pos: Pos, f: &mut std::fmt::Formatter) -> std::fmt::Result {
 		let mnemonic = self.kind.mnemonic();
 		let target = self.target(pos);
diff --git a/dcb-exe/src/exe/inst/basic/jmp/reg.rs b/dcb-exe/src/exe/inst/basic/jmp/reg.rs
index 03b48b4..f4c074a 100644
--- a/dcb-exe/src/exe/inst/basic/jmp/reg.rs
+++ b/dcb-exe/src/exe/inst/basic/jmp/reg.rs
@@ -78,10 +78,6 @@ impl Encodable for Inst {
 }
 
 impl InstFmt for Inst {
-	fn mnemonic(&self) -> &'static str {
-		self.kind.mnemonic()
-	}
-
 	fn fmt(&self, _pos: crate::Pos, f: &mut std::fmt::Formatter) -> std::fmt::Result {
 		let Self { target, kind } = self;
 		let mnemonic = kind.mnemonic();
diff --git a/dcb-exe/src/exe/inst/basic/load.rs b/dcb-exe/src/exe/inst/basic/load.rs
index 4ad89ea..6206c37 100644
--- a/dcb-exe/src/exe/inst/basic/load.rs
+++ b/dcb-exe/src/exe/inst/basic/load.rs
@@ -125,10 +125,6 @@ impl Encodable for Inst {
 }
 
 impl InstFmt for Inst {
-	fn mnemonic(&self) -> &'static str {
-		self.kind.mnemonic()
-	}
-
 	fn fmt(&self, _pos: crate::Pos, f: &mut std::fmt::Formatter) -> std::fmt::Result {
 		let Self { dst, src, offset, kind } = self;
 		let mnemonic = kind.mnemonic();
diff --git a/dcb-exe/src/exe/inst/basic/lui.rs b/dcb-exe/src/exe/inst/basic/lui.rs
index 5633c30..9e556c9 100644
--- a/dcb-exe/src/exe/inst/basic/lui.rs
+++ b/dcb-exe/src/exe/inst/basic/lui.rs
@@ -48,10 +48,6 @@ impl Encodable for Inst {
 
 
 impl InstFmt for Inst {
-	fn mnemonic(&self) -> &'static str {
-		"lui"
-	}
-
 	fn fmt(&self, _pos: crate::Pos, f: &mut std::fmt::Formatter) -> std::fmt::Result {
 		let Self { dst, value } = self;
 
diff --git a/dcb-exe/src/exe/inst/basic/mult.rs b/dcb-exe/src/exe/inst/basic/mult.rs
index 738289d..0517404 100644
--- a/dcb-exe/src/exe/inst/basic/mult.rs
+++ b/dcb-exe/src/exe/inst/basic/mult.rs
@@ -89,6 +89,30 @@ pub enum Inst {
 	},
 }
 
+impl Inst {
+	/// Returns this instruction's mnemonic
+	#[must_use]
+	const fn mnemonic(self) -> &'static str {
+		match self {
+			#[rustfmt::skip]
+			Self::Mult { kind, mode, .. } => match (kind, mode) {
+				(MultKind::Mult, MultMode::  Signed) => "mult",
+				(MultKind::Mult, MultMode::Unsigned) => "multu",
+				(MultKind::Div , MultMode::  Signed) => "div",
+				(MultKind::Div , MultMode::Unsigned) => "diu",
+			},
+			Self::MoveFrom { src, .. } => match src {
+				MultReg::Hi => "mfhi",
+				MultReg::Lo => "mflo",
+			},
+			Self::MoveTo { dst, .. } => match dst {
+				MultReg::Hi => "mthi",
+				MultReg::Lo => "mtlo",
+			},
+		}
+	}
+}
+
 impl Decodable for Inst {
 	type Raw = Raw;
 
@@ -152,30 +176,9 @@ impl Encodable for Inst {
 }
 
 impl InstFmt for Inst {
-	fn mnemonic(&self) -> &'static str {
-		match self {
-			#[rustfmt::skip]
-			Self::Mult { kind, mode, .. } => match (kind, mode) {
-				(MultKind::Mult, MultMode::  Signed) => "mult",
-				(MultKind::Mult, MultMode::Unsigned) => "multu",
-				(MultKind::Div , MultMode::  Signed) => "div",
-				(MultKind::Div , MultMode::Unsigned) => "diu",
-			},
-			Self::MoveFrom { src, .. } => match src {
-				MultReg::Hi => "mfhi",
-				MultReg::Lo => "mflo",
-			},
-			Self::MoveTo { dst, .. } => match dst {
-				MultReg::Hi => "mthi",
-				MultReg::Lo => "mtlo",
-			},
-		}
-	}
-
 	fn fmt(&self, _pos: crate::Pos, f: &mut std::fmt::Formatter) -> std::fmt::Result {
 		let mnemonic = self.mnemonic();
 		match self {
-			#[rustfmt::skip]
 			Self::Mult { lhs, rhs, .. } => write!(f, "{mnemonic} {lhs}, {rhs}"),
 			Self::MoveFrom { dst: arg, .. } | Self::MoveTo { src: arg, .. } => write!(f, "{mnemonic} {arg}"),
 		}
diff --git a/dcb-exe/src/exe/inst/basic/shift.rs b/dcb-exe/src/exe/inst/basic/shift.rs
index 9bd5c2a..8e51bc4 100644
--- a/dcb-exe/src/exe/inst/basic/shift.rs
+++ b/dcb-exe/src/exe/inst/basic/shift.rs
@@ -54,13 +54,6 @@ impl Encodable for Inst {
 }
 
 impl InstFmt for Inst {
-	fn mnemonic(&self) -> &'static str {
-		match self {
-			Self::Imm(inst) => inst.mnemonic(),
-			Self::Reg(inst) => inst.mnemonic(),
-		}
-	}
-
 	fn fmt(&self, pos: crate::Pos, f: &mut std::fmt::Formatter) -> std::fmt::Result {
 		match self {
 			Self::Imm(inst) => inst.fmt(pos, f),
diff --git a/dcb-exe/src/exe/inst/basic/shift/imm.rs b/dcb-exe/src/exe/inst/basic/shift/imm.rs
index 9e9e04f..b27f0b0 100644
--- a/dcb-exe/src/exe/inst/basic/shift/imm.rs
+++ b/dcb-exe/src/exe/inst/basic/shift/imm.rs
@@ -100,10 +100,6 @@ impl Encodable for Inst {
 }
 
 impl InstFmt for Inst {
-	fn mnemonic(&self) -> &'static str {
-		self.kind.mnemonic()
-	}
-
 	fn fmt(&self, _pos: crate::Pos, f: &mut std::fmt::Formatter) -> std::fmt::Result {
 		let Self { dst, lhs, rhs, kind } = self;
 		let mnemonic = kind.mnemonic();
diff --git a/dcb-exe/src/exe/inst/basic/shift/reg.rs b/dcb-exe/src/exe/inst/basic/shift/reg.rs
index 4baa42d..2aacc16 100644
--- a/dcb-exe/src/exe/inst/basic/shift/reg.rs
+++ b/dcb-exe/src/exe/inst/basic/shift/reg.rs
@@ -99,10 +99,6 @@ impl Encodable for Inst {
 }
 
 impl InstFmt for Inst {
-	fn mnemonic(&self) -> &'static str {
-		self.kind.mnemonic()
-	}
-
 	fn fmt(&self, _pos: crate::Pos, f: &mut std::fmt::Formatter) -> std::fmt::Result {
 		let Self { dst, lhs, rhs, kind } = self;
 		let mnemonic = kind.mnemonic();
diff --git a/dcb-exe/src/exe/inst/basic/store.rs b/dcb-exe/src/exe/inst/basic/store.rs
index 1ba927e..1b64117 100644
--- a/dcb-exe/src/exe/inst/basic/store.rs
+++ b/dcb-exe/src/exe/inst/basic/store.rs
@@ -112,10 +112,6 @@ impl Encodable for Inst {
 }
 
 impl InstFmt for Inst {
-	fn mnemonic(&self) -> &'static str {
-		self.kind.mnemonic()
-	}
-
 	fn fmt(&self, _pos: crate::Pos, f: &mut std::fmt::Formatter) -> std::fmt::Result {
 		let Self { dst, src, offset, kind } = self;
 		let mnemonic = kind.mnemonic();
diff --git a/dcb-exe/src/exe/inst/basic/sys.rs b/dcb-exe/src/exe/inst/basic/sys.rs
index 8e736b4..b344681 100644
--- a/dcb-exe/src/exe/inst/basic/sys.rs
+++ b/dcb-exe/src/exe/inst/basic/sys.rs
@@ -75,10 +75,6 @@ impl Encodable for Inst {
 
 
 impl InstFmt for Inst {
-	fn mnemonic(&self) -> &'static str {
-		self.kind.mnemonic()
-	}
-
 	fn fmt(&self, _pos: crate::Pos, f: &mut std::fmt::Formatter) -> std::fmt::Result {
 		let Self { comment, kind } = self;
 		let mnemonic = kind.mnemonic();
diff --git a/dcb-exe/src/exe/inst/directive.rs b/dcb-exe/src/exe/inst/directive.rs
index 3919761..007d368 100644
--- a/dcb-exe/src/exe/inst/directive.rs
+++ b/dcb-exe/src/exe/inst/directive.rs
@@ -153,22 +153,12 @@ impl<'a> InstSize for Directive<'a> {
 }
 
 impl<'a> InstFmt for Directive<'a> {
-	fn mnemonic(&self) -> &'static str {
-		match self {
-			Self::Dw(_) => "dw",
-			Self::Dh(_) => "dh",
-			Self::Db(_) => "db",
-			Self::Ascii { .. } => ".ascii",
-		}
-	}
-
 	fn fmt(&self, _pos: Pos, f: &mut std::fmt::Formatter) -> std::fmt::Result {
-		let mnemonic = self.mnemonic();
 		match self {
-			Self::Dw(value) => write!(f, "{mnemonic} {value:#x}"),
-			Self::Dh(value) => write!(f, "{mnemonic} {value:#x}"),
-			Self::Db(value) => write!(f, "{mnemonic} {value:#x}"),
-			Self::Ascii(string) => write!(f, "{mnemonic} \"{}\"", string.as_str().escape_debug()),
+			Self::Dw(value) => write!(f, "dw {value:#x}"),
+			Self::Dh(value) => write!(f, "dh {value:#x}"),
+			Self::Db(value) => write!(f, "db {value:#x}"),
+			Self::Ascii(string) => write!(f, ".ascii \"{}\"", string.as_str().escape_debug()),
 		}
 	}
 }
diff --git a/dcb-exe/src/exe/inst/fmt.rs b/dcb-exe/src/exe/inst/fmt.rs
index 45480ea..aa02e67 100644
--- a/dcb-exe/src/exe/inst/fmt.rs
+++ b/dcb-exe/src/exe/inst/fmt.rs
@@ -13,9 +13,6 @@ use std::fmt;
 /// branching instructions), as well as the byte array containing the entire
 /// executable.
 pub trait InstFmt {
-	/// Returns this instruction's mnemonic
-	fn mnemonic(&self) -> &'static str;
-
 	/// Formats this instruction
 	fn fmt(&self, pos: Pos, f: &mut fmt::Formatter) -> fmt::Result;
 
diff --git a/dcb-exe/src/exe/inst/pseudo.rs b/dcb-exe/src/exe/inst/pseudo.rs
index 5bebf04..98ba054 100644
--- a/dcb-exe/src/exe/inst/pseudo.rs
+++ b/dcb-exe/src/exe/inst/pseudo.rs
@@ -76,19 +76,6 @@ impl InstSize for Inst {
 }
 
 impl InstFmt for Inst {
-	fn mnemonic(&self) -> &'static str {
-		match self {
-			Self::AluAssign(inst) => inst.mnemonic(),
-			Self::ShiftAssign(inst) => inst.mnemonic(),
-			Self::LoadImm(inst) => inst.mnemonic(),
-			Self::Nop(inst) => inst.mnemonic(),
-			Self::MoveReg(inst) => inst.mnemonic(),
-			Self::Jmp(inst) => inst.mnemonic(),
-			Self::Load(inst) => inst.mnemonic(),
-			Self::Store(inst) => inst.mnemonic(),
-		}
-	}
-
 	fn fmt(&self, pos: crate::Pos, f: &mut std::fmt::Formatter) -> std::fmt::Result {
 		match self {
 			Self::AluAssign(inst) => inst.fmt(pos, f),
diff --git a/dcb-exe/src/exe/inst/pseudo/alu_assign.rs b/dcb-exe/src/exe/inst/pseudo/alu_assign.rs
index 983d108..97e30b0 100644
--- a/dcb-exe/src/exe/inst/pseudo/alu_assign.rs
+++ b/dcb-exe/src/exe/inst/pseudo/alu_assign.rs
@@ -85,10 +85,6 @@ impl InstSize for Inst {
 }
 
 impl InstFmt for Inst {
-	fn mnemonic(&self) -> &'static str {
-		self.kind.mnemonic()
-	}
-
 	fn fmt(&self, _pos: crate::Pos, f: &mut std::fmt::Formatter) -> std::fmt::Result {
 		let Self { dst, kind } = self;
 		let mnemonic = kind.mnemonic();
diff --git a/dcb-exe/src/exe/inst/pseudo/jmp.rs b/dcb-exe/src/exe/inst/pseudo/jmp.rs
index 27789bf..db0198e 100644
--- a/dcb-exe/src/exe/inst/pseudo/jmp.rs
+++ b/dcb-exe/src/exe/inst/pseudo/jmp.rs
@@ -77,22 +77,12 @@ impl InstSize for Inst {
 }
 
 impl InstFmt for Inst {
-	fn mnemonic(&self) -> &'static str {
-		match self {
-			Self::JalrRa { .. } => "jalr",
-			Self::Beqz { .. } => "beqz",
-			Self::Bnez { .. } => "bnez",
-			Self::B { .. } => "b",
-		}
-	}
-
 	fn fmt(&self, pos: crate::Pos, f: &mut std::fmt::Formatter) -> std::fmt::Result {
-		let mnemonic = self.mnemonic();
-
 		match *self {
-			Self::JalrRa { target } => write!(f, "{mnemonic} {target}"),
-			Self::Beqz { arg, offset } | Self::Bnez { arg, offset } => write!(f, "{mnemonic} {arg}, {}", basic::cond::Inst::target_of(offset, pos)),
-			Self::B { offset } => write!(f, "{mnemonic} {}", basic::cond::Inst::target_of(offset, pos)),
+			Self::JalrRa { target } => write!(f, "jalr {target}"),
+			Self::Beqz { arg, offset } => write!(f, "beqz {arg}, {}", basic::cond::Inst::target_of(offset, pos)),
+			Self::Bnez { arg, offset } => write!(f, "bnez {arg}, {}", basic::cond::Inst::target_of(offset, pos)),
+			Self::B { offset } => write!(f, "b {}", basic::cond::Inst::target_of(offset, pos)),
 		}
 	}
 }
diff --git a/dcb-exe/src/exe/inst/pseudo/load.rs b/dcb-exe/src/exe/inst/pseudo/load.rs
index 014a4fd..b2284c6 100644
--- a/dcb-exe/src/exe/inst/pseudo/load.rs
+++ b/dcb-exe/src/exe/inst/pseudo/load.rs
@@ -53,10 +53,6 @@ impl InstSize for Inst {
 }
 
 impl InstFmt for Inst {
-	fn mnemonic(&self) -> &'static str {
-		self.kind.mnemonic()
-	}
-
 	fn fmt(&self, _pos: crate::Pos, f: &mut std::fmt::Formatter) -> std::fmt::Result {
 		let Self { dst, kind, target } = self;
 		let mnemonic = kind.mnemonic();
diff --git a/dcb-exe/src/exe/inst/pseudo/load_imm.rs b/dcb-exe/src/exe/inst/pseudo/load_imm.rs
index 07dd289..b8d15be 100644
--- a/dcb-exe/src/exe/inst/pseudo/load_imm.rs
+++ b/dcb-exe/src/exe/inst/pseudo/load_imm.rs
@@ -112,10 +112,6 @@ impl InstSize for Inst {
 }
 
 impl InstFmt for Inst {
-	fn mnemonic(&self) -> &'static str {
-		self.kind.mnemonic()
-	}
-
 	fn fmt(&self, _pos: crate::Pos, f: &mut std::fmt::Formatter) -> std::fmt::Result {
 		let Self { dst, kind } = self;
 		let mnemonic = kind.mnemonic();
diff --git a/dcb-exe/src/exe/inst/pseudo/move_reg.rs b/dcb-exe/src/exe/inst/pseudo/move_reg.rs
index 6548877..f27a040 100644
--- a/dcb-exe/src/exe/inst/pseudo/move_reg.rs
+++ b/dcb-exe/src/exe/inst/pseudo/move_reg.rs
@@ -43,14 +43,9 @@ impl InstSize for Inst {
 }
 
 impl InstFmt for Inst {
-	fn mnemonic(&self) -> &'static str {
-		"move"
-	}
-
 	fn fmt(&self, _pos: crate::Pos, f: &mut std::fmt::Formatter) -> std::fmt::Result {
 		let Self { dst, src } = self;
-		let mnemonic = self.mnemonic();
 
-		write!(f, "{mnemonic} {dst}, {src}")
+		write!(f, "move {dst}, {src}")
 	}
 }
diff --git a/dcb-exe/src/exe/inst/pseudo/nop.rs b/dcb-exe/src/exe/inst/pseudo/nop.rs
index 947b997..a18ecbf 100644
--- a/dcb-exe/src/exe/inst/pseudo/nop.rs
+++ b/dcb-exe/src/exe/inst/pseudo/nop.rs
@@ -44,16 +44,10 @@ impl InstSize for Inst {
 }
 
 impl InstFmt for Inst {
-	fn mnemonic(&self) -> &'static str {
-		"nop"
-	}
-
 	fn fmt(&self, _pos: crate::Pos, f: &mut std::fmt::Formatter) -> std::fmt::Result {
-		let mnemonic = self.mnemonic();
-
 		match self.len {
-			1 => write!(f, "{mnemonic}"),
-			len => write!(f, "{mnemonic} {}", len),
+			1 => write!(f, "nop"),
+			len => write!(f, "nop {}", len),
 		}
 	}
 }
diff --git a/dcb-exe/src/exe/inst/pseudo/shift_assign.rs b/dcb-exe/src/exe/inst/pseudo/shift_assign.rs
index 5270eef..1dbefb2 100644
--- a/dcb-exe/src/exe/inst/pseudo/shift_assign.rs
+++ b/dcb-exe/src/exe/inst/pseudo/shift_assign.rs
@@ -88,10 +88,6 @@ impl InstSize for Inst {
 }
 
 impl InstFmt for Inst {
-	fn mnemonic(&self) -> &'static str {
-		self.kind.mnemonic()
-	}
-
 	fn fmt(&self, _pos: crate::Pos, f: &mut std::fmt::Formatter) -> std::fmt::Result {
 		let Self { dst, kind } = self;
 		let mnemonic = kind.mnemonic();
diff --git a/dcb-exe/src/exe/inst/pseudo/store.rs b/dcb-exe/src/exe/inst/pseudo/store.rs
index 0d3e1fe..b1a9ae9 100644
--- a/dcb-exe/src/exe/inst/pseudo/store.rs
+++ b/dcb-exe/src/exe/inst/pseudo/store.rs
@@ -53,10 +53,6 @@ impl InstSize for Inst {
 }
 
 impl InstFmt for Inst {
-	fn mnemonic(&self) -> &'static str {
-		self.kind.mnemonic()
-	}
-
 	fn fmt(&self, _pos: crate::Pos, f: &mut std::fmt::Formatter) -> std::fmt::Result {
 		let Self { dst, kind, target } = self;
 		let mnemonic = kind.mnemonic();