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diff --git a/src/predicate.rs b/src/predicate.rs
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+/*
+	Copyright 2021-2023 Gabriel Jensen.
+
+	This file is part of Luma.
+
+	Luma is free software: you can redistribute it
+	and/or modify it under the terms of the GNU
+	Affero General Public License as published by
+	the Free Software Foundation, either version 3
+	of the License, or (at your option) any later
+	version.
+
+	Luma is distributed in the hope that it will be
+	useful, but WITHOUT ANY WARRANTY; without even
+	the implied warranty of MERCHANTABILITY or
+	FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+	Affero General Public License for more details.
+
+	You should have received a copy of the GNU
+	Affero General Public License along with Luma.
+	If not, see <https://www.gnu.org/licenses/>.
+*/
+
+use std::mem::transmute;
+
+#[derive(Clone, Copy)]
+#[repr(u8)]
+pub enum Predicate {
+	Eq = 0b0000,
+	Ne = 0b0001,
+	Cs = 0b0010, // Hs
+	Cc = 0b0011, // Lo
+	Mi = 0b0100,
+	Pl = 0b0101,
+	Vs = 0b0110,
+	Vc = 0b0111,
+	Hi = 0b1000,
+	Ls = 0b1001,
+	Ge = 0b1010,
+	Lt = 0b1011,
+	Gt = 0b1100,
+	Le = 0b1101,
+	Al = 0b1110,
+	Nv = 0b1111,
+}
+
+impl Predicate {
+	pub fn from_raw(mut raw: u8) -> Self {
+		raw &= 0b00001111;
+		return unsafe { transmute(raw) };
+	}
+
+	pub fn test(self, cpsr: u32) -> bool {
+		let v = cpsr & 0b00010000000000000000000000000000 != 0x0;
+		let c = cpsr & 0b00100000000000000000000000000000 != 0x0;
+		let z = cpsr & 0b01000000000000000000000000000000 != 0x0;
+		let n = cpsr & 0b10000000000000000000000000000000 != 0x0;
+
+		use Predicate::*;
+		return match self {
+			Eq => z,
+			Ne => !z,
+			Cs => c,
+			Cc => !c,
+			Mi => n,
+			Pl => !n,
+			Vs => v,
+			Vc => !v,
+			Hi => c && !z,
+			Ls => !c && z,
+			Ge => n == v,
+			Lt => n != v,
+			Gt => !z && n == v,
+			Le => z && n != v,
+			Al => true,
+			Nv => false, // Unpredictable in ARMv4.
+		};
+	}
+
+	pub fn code(self) -> &'static str {
+		use Predicate::*;
+		return match self {
+			Eq => "eq",
+			Ne => "ne",
+			Cs => "cs",
+			Cc => "cc",
+			Mi => "mi",
+			Pl => "pl",
+			Vs => "vs",
+			Vc => "vc",
+			Hi => "hi",
+			Ls => "ls",
+			Ge => "ge",
+			Lt => "lt",
+			Gt => "gt",
+			Le => "le",
+			Al => "al",
+			Nv => "nv",
+		};
+	}
+}