From 2b3900fd14c3de525e9e291947584b887bae0e56 Mon Sep 17 00:00:00 2001
From: Thomas Harte <thomas.harte@gmail.com>
Date: Sat, 7 May 2022 08:15:26 -0400
Subject: [PATCH] Fix LINK A7.

---
 InstructionSets/M68k/Executor.hpp                         | 2 +-
 .../M68k/Implementation/ExecutorImplementation.hpp        | 8 +++++---
 .../M68k/Implementation/PerformImplementation.hpp         | 2 +-
 InstructionSets/M68k/Instruction.hpp                      | 2 +-
 OSBindings/Mac/Clock SignalTests/68000ComparativeTests.mm | 2 +-
 5 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/InstructionSets/M68k/Executor.hpp b/InstructionSets/M68k/Executor.hpp
index 6c35cde9b..970da704e 100644
--- a/InstructionSets/M68k/Executor.hpp
+++ b/InstructionSets/M68k/Executor.hpp
@@ -48,7 +48,7 @@ template <Model model, typename BusHandler> class Executor {
 
 		void bsr(uint32_t offset);
 		void jsr(uint32_t offset);
-		void link(uint32_t &address, uint32_t offset);
+		void link(Preinstruction instruction, uint32_t offset);
 		void unlink(uint32_t &address);
 		template <typename IntT> void movep(Preinstruction instruction, uint32_t source, uint32_t dest);
 		template <typename IntT> void movem_toM(Preinstruction instruction, uint32_t source, uint32_t dest);
diff --git a/InstructionSets/M68k/Implementation/ExecutorImplementation.hpp b/InstructionSets/M68k/Implementation/ExecutorImplementation.hpp
index 5b232e632..03b1f0069 100644
--- a/InstructionSets/M68k/Implementation/ExecutorImplementation.hpp
+++ b/InstructionSets/M68k/Implementation/ExecutorImplementation.hpp
@@ -381,10 +381,12 @@ void Executor<model, BusHandler>::jsr(uint32_t address) {
 }
 
 template <Model model, typename BusHandler>
-void Executor<model, BusHandler>::link(uint32_t &address, uint32_t offset) {
+void Executor<model, BusHandler>::link(Preinstruction instruction, uint32_t offset) {
+	const auto reg = 8 + instruction.reg<0>();
+
 	sp().l -= 4;
-	bus_handler_.template write<uint32_t>(sp().l, address);
-	address = sp().l;
+	bus_handler_.template write<uint32_t>(sp().l, registers_[reg].l);
+	registers_[reg] = sp();
 	sp().l += offset;
 }
 
diff --git a/InstructionSets/M68k/Implementation/PerformImplementation.hpp b/InstructionSets/M68k/Implementation/PerformImplementation.hpp
index 2f98a4b4a..42cc8c73a 100644
--- a/InstructionSets/M68k/Implementation/PerformImplementation.hpp
+++ b/InstructionSets/M68k/Implementation/PerformImplementation.hpp
@@ -781,7 +781,7 @@ template <
 		*/
 
 		case Operation::LINKw:
-			flow_controller.link(src.l, int16_t(dest.w));
+			flow_controller.link(instruction, int16_t(dest.w));
 		break;
 
 		case Operation::UNLINK:
diff --git a/InstructionSets/M68k/Instruction.hpp b/InstructionSets/M68k/Instruction.hpp
index b189259a9..bb81ab0fd 100644
--- a/InstructionSets/M68k/Instruction.hpp
+++ b/InstructionSets/M68k/Instruction.hpp
@@ -331,6 +331,7 @@ template <Model model, Operation t_operation = Operation::Undefined> uint8_t ope
 		case Operation::CMPAw:	case Operation::CMPAl:
 		case Operation::CHK:
 		case Operation::BTST:
+		case Operation::LINKw:
 			return FetchOp1 | FetchOp2;
 
 		//
@@ -371,7 +372,6 @@ template <Model model, Operation t_operation = Operation::Undefined> uint8_t ope
 		// Two-operand; read both, write source.
 		//
 		case Operation::DBcc:
-		case Operation::LINKw:
 			return FetchOp1 | FetchOp2 | StoreOp1;
 
 		//
diff --git a/OSBindings/Mac/Clock SignalTests/68000ComparativeTests.mm b/OSBindings/Mac/Clock SignalTests/68000ComparativeTests.mm
index bb54dd6e5..21d6327ef 100644
--- a/OSBindings/Mac/Clock SignalTests/68000ComparativeTests.mm	
+++ b/OSBindings/Mac/Clock SignalTests/68000ComparativeTests.mm	
@@ -83,7 +83,7 @@
 
 - (void)setUp {
 	// To limit tests run to a subset of files and/or of tests, uncomment and fill in below.
-//	_fileSet = [NSSet setWithArray:@[@"rts.json", @"rtr.json"]];
+//	_fileSet = [NSSet setWithArray:@[@"link_unlk.json"]];
 //	_testSet = [NSSet setWithArray:@[@"NEGX 00c0"]];
 //	_fileSet = [NSSet setWithArray:@[@"jmp_jsr.json"]];
 //	_testSet = [NSSet setWithArray:@[@"CHK 41a8"]];