diff --git a/Processors/Decoders/x86/x86.cpp b/Processors/Decoders/x86/x86.cpp
index 7a8e38de2..ae890a476 100644
--- a/Processors/Decoders/x86/x86.cpp
+++ b/Processors/Decoders/x86/x86.cpp
@@ -165,8 +165,11 @@ std::pair<int, Instruction> Decoder::decode(const uint8_t *source, size_t length
 
 			// TODO:
 			//
-			//	0x80, 0x81, 0x82, 0x83, which all require more
-			//	input, from the ModRegRM byte.
+			//	0x82, 0x83, which will require me to do something
+			//	re: word-sign extended.
+
+			case 0x80: MemRegReg(Invalid, MemRegADD_to_CMP, 1);	break;
+			case 0x81: MemRegReg(Invalid, MemRegADD_to_CMP, 2);	break;
 
 			case 0x84: MemRegReg(TEST, MemReg_Reg, 1);	break;
 			case 0x85: MemRegReg(TEST, MemReg_Reg, 2);	break;
@@ -503,6 +506,22 @@ std::pair<int, Instruction> Decoder::decode(const uint8_t *source, size_t length
 				operand_size_ = operation_size_;
 			break;
 
+			case ModRegRMFormat::MemRegADD_to_CMP:
+				destination_ = memreg;
+				operand_size_ = operation_size_;
+
+				switch(reg) {
+					default:	operation_ = Operation::ADD;	break;
+					case 1:		operation_ = Operation::OR;		break;
+					case 2:		operation_ = Operation::ADC;	break;
+					case 3:		operation_ = Operation::SBB;	break;
+					case 4:		operation_ = Operation::AND;	break;
+					case 5:		operation_ = Operation::SUB;	break;
+					case 6:		operation_ = Operation::XOR;	break;
+					case 7:		operation_ = Operation::CMP;	break;
+				}
+			break;
+
 			default: assert(false);
 		}
 
diff --git a/Processors/Decoders/x86/x86.hpp b/Processors/Decoders/x86/x86.hpp
index aaab81365..d39da8f88 100644
--- a/Processors/Decoders/x86/x86.hpp
+++ b/Processors/Decoders/x86/x86.hpp
@@ -238,6 +238,12 @@ struct Decoder {
 			// to pick an operation from the ROL/ROR/RCL/RCR/SAL/SHR/SAR group.
 			MemRegROL_to_SAR,
 
+			// Parse for mode and register/memory fields, populating the
+			// destination_ field with the result. Use the 'register' field
+			// to pick an operation from the ADD/OR/ADC/SBB/AND/SUB/XOR/CMP group and
+			// waits for an operand equal to the operation size.
+			MemRegADD_to_CMP,
+
 			// Parse for mode and register/memory fields, populating the
 			// source_ field with the result. Fills destination_ with a segment
 			// register based on the reg field.