1 files changed, 105 insertions, 6 deletions
diff --git a/src/arm32/register/mod.rs b/src/arm32/register/mod.rs
index 2df521b..0013c46 100644
--- a/src/arm32/register/mod.rs
+++ b/src/arm32/register/mod.rs
@@ -19,7 +19,10 @@
 // fero General Public License along with Pollex.
 // If not, see <https://www.gnu.org/licenses/>.
 
+use crate::Error;
+
 use core::fmt::Display;
+use core::str::FromStr;
 
 /// An Arm register.
 ///
@@ -38,15 +41,33 @@ pub enum Register {
 	R6  = 0b0110,
 	R7  = 0b0111,
 	R8  = 0b1000,
-	Sb  = 0b1001, // R9
-	Sl  = 0b1010, // R10
+	R9  = 0b1001, // Sb
+	R10 = 0b1010, // Sl
 	R11 = 0b1011,
-	Ip  = 0b1100, // R12
+	R12 = 0b1100, // Ip
 	Sp  = 0b1101, // R13
 	Lr  = 0b1110, // R14
 	Pc  = 0b1111, // R15
 }
 
+impl Register {
+	/// Checks if the register is a low register.
+	///
+	/// That is, it is any of `r0`, `r1`, `r2`, `r3`, `r4`, `r5`, `r6`, or `r7` -- or any alias herof.
+	/// See also [`is_high`](Self::is_high).
+	#[inline(always)]
+	#[must_use]
+	pub const fn is_low(self) -> bool { (self as u8) <= 0x7 }
+
+	/// Checks if the register is a high register.
+	///
+	/// That is, it is any of `r8`, `r9`, `r10`, `r11`, `r12`, `sp`, `lr`, or `pc` -- or any alias herof.
+	/// See also [`is_low`](Self::is_low).
+	#[inline(always)]
+	#[must_use]
+	pub const fn is_high(self) -> bool { (self as u8) > 0x7 }
+}
+
 impl Display for Register {
 	fn fmt(&self, f: &mut core::fmt::Formatter) -> core::fmt::Result {
 		use Register::*;
@@ -61,13 +82,91 @@ impl Display for Register {
 			R6  => write!(f, "r6"),
 			R7  => write!(f, "r7"),
 			R8  => write!(f, "r8"),
-			Sb  => write!(f, "sb"),
-			Sl  => write!(f, "sl"),
+			R9  => write!(f, "r9"),
+			R10 => write!(f, "r10"),
 			R11 => write!(f, "r11"),
-			Ip  => write!(f, "ip"),
+			R12 => write!(f, "r12"),
 			Sp  => write!(f, "sp"),
 			Lr  => write!(f, "lr"),
 			Pc  => write!(f, "pc"),
 		}
 	}
 }
+
+impl FromStr for Register {
+	type Err = Error;
+
+	fn from_str(s: &str) -> Result<Self, Self::Err> {
+		use Register::*;
+
+		match s.to_lowercase().as_str() {
+			| "r0"
+			| "a1"
+			=> Ok(R0),
+
+			| "r1"
+			| "a2"
+			=> Ok(R1),
+
+			| "r2"
+			| "a3"
+			=> Ok(R2),
+
+			| "r3"
+			| "a4"
+			=> Ok(R3),
+
+			| "r4"
+			| "v1"
+			=> Ok(R4),
+
+			| "r5"
+			| "v2"
+			=> Ok(R5),
+
+			| "r6"
+			| "v3"
+			=> Ok(R6),
+
+			| "r7"
+			| "v4"
+			=> Ok(R7),
+
+			| "r8"
+			| "v5"
+			=> Ok(R8),
+
+			| "r9"
+			| "sb"
+			| "v6"
+			=> Ok(R9),
+
+			| "r10"
+			| "sl"
+			| "v7"
+			=> Ok(R10),
+
+			| "r11"
+			| "v8"
+			=> Ok(R11),
+
+			| "ip"
+			| "r12"
+			=> Ok(R12),
+
+			| "r13"
+			| "sp"
+			=> Ok(Sp),
+
+			| "lr"
+			| "r14"
+			=> Ok(Lr),
+
+			| "pc"
+			| "r15"
+			=> Ok(Pc),
+
+			_ => Err(Error::UnknownRegister)
+		}
+	}
+}