diff --git a/InstructionSets/x86/Implementation/BCD.hpp b/InstructionSets/x86/Implementation/BCD.hpp
index 2ea8e37db..97519cc6a 100644
--- a/InstructionSets/x86/Implementation/BCD.hpp
+++ b/InstructionSets/x86/Implementation/BCD.hpp
@@ -47,6 +47,39 @@ void aaa(
 	ax.halves.low &= 0x0f;
 }
 
+
+template <typename ContextT>
+void aas(
+	CPU::RegisterPair16 &ax,
+	ContextT &context
+) {
+	/*
+		IF ((AL AND 0FH) > 9) OR (AF = 1)
+		THEN
+			AL ← AL – 6;
+			AH ← AH – 1;
+			AF ← 1;
+			CF ← 1;
+		ELSE
+			CF ← 0;
+			AF ← 0;
+		FI;
+		AL ← AL AND 0FH;
+	*/
+	/*
+		The AF and CF flags are set to 1 if there is a decimal borrow;
+		otherwise, they are cleared to 0. The OF, SF, ZF, and PF flags are undefined.
+	*/
+	if((ax.halves.low & 0x0f) > 9 || context.flags.template flag<Flag::AuxiliaryCarry>()) {
+		ax.halves.low -= 6;
+		--ax.halves.high;
+		context.flags.template set_from<Flag::Carry, Flag::AuxiliaryCarry>(1);
+	} else {
+		context.flags.template set_from<Flag::Carry, Flag::AuxiliaryCarry>(0);
+	}
+	ax.halves.low &= 0x0f;
+}
+
 template <typename ContextT>
 void aad(
 	CPU::RegisterPair16 &ax,
@@ -96,40 +129,9 @@ void aam(
 	context.flags.template set_from<uint8_t, Flag::Zero, Flag::Sign, Flag::ParityOdd>(ax.halves.low);
 }
 
-template <typename ContextT>
-void aas(
-	CPU::RegisterPair16 &ax,
-	ContextT &context
-) {
-	/*
-		IF ((AL AND 0FH) > 9) OR (AF = 1)
-		THEN
-			AL ← AL – 6;
-			AH ← AH – 1;
-			AF ← 1;
-			CF ← 1;
-		ELSE
-			CF ← 0;
-			AF ← 0;
-		FI;
-		AL ← AL AND 0FH;
-	*/
-	/*
-		The AF and CF flags are set to 1 if there is a decimal borrow;
-		otherwise, they are cleared to 0. The OF, SF, ZF, and PF flags are undefined.
-	*/
-	if((ax.halves.low & 0x0f) > 9 || context.flags.template flag<Flag::AuxiliaryCarry>()) {
-		ax.halves.low -= 6;
-		--ax.halves.high;
-		context.flags.template set_from<Flag::Carry, Flag::AuxiliaryCarry>(1);
-	} else {
-		context.flags.template set_from<Flag::Carry, Flag::AuxiliaryCarry>(0);
-	}
-	ax.halves.low &= 0x0f;
-}
-
-template <typename ContextT>
-void daa(
+/// If @c add is @c true, performs a DAA; otherwise perfoms a DAS.
+template <bool add, typename ContextT>
+void daas(
 	uint8_t &al,
 	ContextT &context
 ) {
@@ -141,39 +143,18 @@ void daa(
 	}
 
 	if((al & 0x0f) > 0x09 || context.flags.template flag<Flag::AuxiliaryCarry>()) {
-		al += 0x06;
+		if constexpr (add) al += 0x06; else al -= 0x06;
 		context.flags.template set_from<Flag::AuxiliaryCarry>(1);
 	}
 
 	if(top_exceeded_threshold || context.flags.template flag<Flag::Carry>()) {
-		al += 0x60;
+		if constexpr (add) al += 0x60; else al -= 0x60;
 		context.flags.template set_from<Flag::Carry>(1);
 	}
 
 	context.flags.template set_from<uint8_t, Flag::Zero, Flag::Sign, Flag::ParityOdd>(al);
 }
 
-template <typename ContextT>
-void das(
-	uint8_t &al,
-	ContextT &context
-) {
-	const uint8_t old_al = al;
-
-	if((al & 0x0f) > 0x09 || context.flags.template flag<Flag::AuxiliaryCarry>()) {
-		al -= 0x06;
-		context.flags.template set_from<Flag::AuxiliaryCarry>(1);
-	}
-
-	if(old_al > 0x99 || context.flags.template flag<Flag::Carry>()) {
-		al -= 0x60;
-		context.flags.template set_from<Flag::Carry>(1);
-	}
-
-	context.flags.template set_from<uint8_t, Flag::Zero, Flag::Sign, Flag::ParityOdd>(al);
-}
-
-
 }
 
 #endif /* BCD_h */
diff --git a/InstructionSets/x86/Implementation/PerformImplementation.hpp b/InstructionSets/x86/Implementation/PerformImplementation.hpp
index 1090d4a17..6a13c2254 100644
--- a/InstructionSets/x86/Implementation/PerformImplementation.hpp
+++ b/InstructionSets/x86/Implementation/PerformImplementation.hpp
@@ -179,8 +179,8 @@ template <
 		case Operation::AAD:	Primitive::aad(context.registers.axp(), instruction.operand(), context);	return;
 		case Operation::AAM:	Primitive::aam(context.registers.axp(), instruction.operand(), context);	return;
 		case Operation::AAS:	Primitive::aas(context.registers.axp(), context);							return;
-		case Operation::DAA:	Primitive::daa(context.registers.al(), context);							return;
-		case Operation::DAS:	Primitive::das(context.registers.al(), context);							return;
+		case Operation::DAA:	Primitive::daas<true>(context.registers.al(), context);						return;
+		case Operation::DAS:	Primitive::daas<false>(context.registers.al(), context);					return;
 
 		case Operation::CBW:	Primitive::cbw(pair_low());					return;
 		case Operation::CWD:	Primitive::cwd(pair_high(), pair_low());	return;
diff --git a/OSBindings/Mac/Clock SignalTests/8088Tests.mm b/OSBindings/Mac/Clock SignalTests/8088Tests.mm
index 2c96678b7..ec08966ab 100644
--- a/OSBindings/Mac/Clock SignalTests/8088Tests.mm	
+++ b/OSBindings/Mac/Clock SignalTests/8088Tests.mm	
@@ -394,8 +394,6 @@ struct FailedExecution {
 	NSString *path = [NSString stringWithUTF8String:TestSuiteHome];
 	NSSet *allowList = [NSSet setWithArray:@[
 		// Current execution failures:
-//		@"27.json.gz",		// DAA
-//		@"2F.json.gz",		// DAS
 //		@"D4.json.gz",		// AAM
 //		@"F6.7.json.gz",	// IDIV
 //		@"F7.7.json.gz",	// IDIV
@@ -459,8 +457,6 @@ struct FailedExecution {
 		return hexInstruction;
 	};
 
-	EACCES;
-
 	const auto decoded = decoder.decode(data.data(), data.size());
 	const bool sizeMatched = decoded.first == data.size();
 	if(assert) {
@@ -576,6 +572,10 @@ struct FailedExecution {
 
 	execution_support.clear();
 
+	if([test[@"test_hash"] isEqualTo:@"503062cab62a583b2884554dfd332d01ab4cc7355b49a1b0523fcbf3e22777a4"]) {
+		printf("");
+	}
+
 	const uint16_t flags_mask = metadata[@"flags-mask"] ? [metadata[@"flags-mask"] intValue] : 0xffff;
 	NSDictionary *const initial_state = test[@"initial"];
 	NSDictionary *const final_state = test[@"final"];
@@ -748,10 +748,9 @@ struct FailedExecution {
 	}
 
 	// Lock in current failure rate.
-	XCTAssertLessThanOrEqual(execution_failures.size(), 4138);
+	XCTAssertLessThanOrEqual(execution_failures.size(), 4009);
 
 	// Current accepted failures:
-	//	* 65 instances of DAA with invalid BCD input, and 64 of DAS;
 	//	* 2484 instances of LEA from a register, which officially has undefined results;
 	//	* 42 instances of AAM 00h for which I can't figure out what to do with flags; and
 	//	* 1486 instances of IDIV, most either with a rep or repne that on the 8086 specifically negatives the result,