From e948a678145dcca0ea9bca6c981efeb0f1049e17 Mon Sep 17 00:00:00 2001
From: Thomas Harte <thomas.harte@gmail.com>
Date: Thu, 12 Oct 2023 13:54:51 -0400
Subject: [PATCH] Implement SAHF, LAHF.

---
 .../Implementation/PerformImplementation.hpp  | 28 +++++++++++++++++++
 OSBindings/Mac/Clock SignalTests/8088Tests.mm | 10 ++++---
 2 files changed, 34 insertions(+), 4 deletions(-)

diff --git a/InstructionSets/x86/Implementation/PerformImplementation.hpp b/InstructionSets/x86/Implementation/PerformImplementation.hpp
index f1defbfe5..88e35246a 100644
--- a/InstructionSets/x86/Implementation/PerformImplementation.hpp
+++ b/InstructionSets/x86/Implementation/PerformImplementation.hpp
@@ -1,4 +1,5 @@
 //
+//
 //  PerformImplementation.hpp
 //  Clock Signal
 //
@@ -789,6 +790,30 @@ void into(Status &status, FlowControllerT &flow_controller) {
 	}
 }
 
+inline void sahf(uint8_t &ah, Status &status) {
+	/*
+		EFLAGS(SF:ZF:0:AF:0:PF:1:CF) ← AH;
+	*/
+	status.set_from<uint8_t, Flag::Sign>(ah);
+	status.set_from<Flag::Zero>(!(ah & 0x40));
+	status.set_from<Flag::AuxiliaryCarry>(ah & 0x10);
+	status.set_from<Flag::ParityOdd>(!(ah & 0x04));
+	status.set_from<Flag::Carry>(ah & 0x01);
+}
+
+inline void lahf(uint8_t &ah, Status &status) {
+	/*
+		AH ← EFLAGS(SF:ZF:0:AF:0:PF:1:CF);
+	*/
+	ah =
+		(status.flag<Flag::Sign>() ? 0x80 : 0x00)	|
+		(status.flag<Flag::Zero>() ? 0x40 : 0x00)	|
+		(status.flag<Flag::AuxiliaryCarry>() ? 0x10 : 0x00)	|
+		(status.flag<Flag::ParityOdd>() ? 0x00 : 0x04)	|
+		0x02 |
+		(status.flag<Flag::Carry>() ? 0x01 : 0x00);
+}
+
 template <typename IntT>
 void cbw(IntT &ax) {
 	constexpr IntT test_bit = 1 << (sizeof(IntT) * 4 - 1);
@@ -941,6 +966,9 @@ template <
 		case Operation::INT:	Primitive::int_(instruction.operand(), flow_controller);	return;
 		case Operation::INTO:	Primitive::into(status, flow_controller);					return;
 
+		case Operation::SAHF:	Primitive::sahf(registers.ah(), status);					return;
+		case Operation::LAHF:	Primitive::lahf(registers.ah(), status);					return;
+
 		case Operation::JO:		jcc(status.condition<Condition::Overflow>());		return;
 		case Operation::JNO:	jcc(!status.condition<Condition::Overflow>());		return;
 		case Operation::JB:		jcc(status.condition<Condition::Below>());			return;
diff --git a/OSBindings/Mac/Clock SignalTests/8088Tests.mm b/OSBindings/Mac/Clock SignalTests/8088Tests.mm
index d9cfb059e..ed157cf01 100644
--- a/OSBindings/Mac/Clock SignalTests/8088Tests.mm	
+++ b/OSBindings/Mac/Clock SignalTests/8088Tests.mm	
@@ -282,7 +282,7 @@ struct FailedExecution {
 - (NSArray<NSString *> *)testFiles {
 	NSString *path = [NSString stringWithUTF8String:TestSuiteHome];
 	NSSet *allowList = [NSSet setWithArray:@[
-		@"37.json.gz",	// AAA
+/*		@"37.json.gz",	// AAA
 		@"3F.json.gz",	// AAS
 		@"D4.json.gz",	// AAM
 		@"D5.json.gz",	// AAD
@@ -371,8 +371,10 @@ struct FailedExecution {
 
 		// INT, INT3
 		@"CC.json.gz", @"CD.json.gz",
+*/
+		@"9E.json.gz",	// SAHF
+		@"9F.json.gz",	// LAHF
 
-		// TODO: LAHF, SAHF
 		// TODO: LDS, LES
 		// TODO: LEA
 
@@ -381,7 +383,7 @@ struct FailedExecution {
 		// TODO: LOOP, LOOPE, LOOPNE
 
 		// TODO: MOV
-
+/*
 		// AND
 		@"20.json.gz",	@"21.json.gz",	@"22.json.gz",	@"23.json.gz",	@"24.json.gz",	@"25.json.gz",
 		@"80.4.json.gz", @"81.4.json.gz", @"83.4.json.gz",
@@ -431,7 +433,7 @@ struct FailedExecution {
 
 		// TODO: XLAT
 		// TODO: SALC, SETMO, SETMOC
-
+*/
 	]];
 
 	NSSet *ignoreList = nil;