Jump opcodes (minus RTI)

src/opcode/handler/jump-opcode-handler-container.cpp

@@ -0,0 +1,44 @@
+#include "jump-opcode-handler-container.h"
+#include "../../utils.h"
+
+namespace emu_6502 {
+    JumpOpcodeHandlerContainer::JumpOpcodeHandlerContainer() {
+        handlers.insert({Op::JMP_ABS, [this](Machine& machine) { jmp_abs(machine); }});
+        handlers.insert({Op::JMP_IND, [this](Machine& machine) { jmp_ind(machine); }});
+
+        handlers.insert({Op::JSR, [this](Machine& machine) { jsr(machine); }});
+
+        handlers.insert({Op::RTI, [this](Machine& machine) { rti(machine); }});
+        handlers.insert({Op::RTS, [this](Machine& machine) { rts(machine); }});
+    }
+
+    void JumpOpcodeHandlerContainer::jmp_abs(Machine& machine) {
+        auto addr = get_abs_address(machine);
+        machine.get_cpu().get_pc().set_value(addr);
+    }
+
+    void JumpOpcodeHandlerContainer::jmp_ind(Machine& machine) {
+        auto addr = get_ind_address(machine);
+        machine.get_cpu().get_pc().set_value(addr);
+    }
+
+    void JumpOpcodeHandlerContainer::jsr(Machine& machine) {
+        uint16_t addr = get_abs_address(machine);
+
+        uint16_t pc_value = machine.get_cpu().get_pc().get_value();
+        machine.get_stack().push(pc_value >> 8);
+        machine.get_stack().push(pc_value);
+
+        machine.get_cpu().get_pc().set_value(addr);
+    }
+
+    void JumpOpcodeHandlerContainer::rti(Machine& machine) {}
+
+    void JumpOpcodeHandlerContainer::rts(Machine& machine) {
+        auto low_byte = machine.get_stack().pop();
+        auto high_byte = machine.get_stack().pop();
+
+        uint16_t return_address = (high_byte << 8) + low_byte + 1;
+        machine.get_cpu().get_pc().set_value(return_address);
+    }
+}

src/opcode/handler/jump-opcode-handler-container.h

@@ -0,0 +1,35 @@
+#ifndef INC_6502_EMULATOR_JUMP_OPCODE_HANDLER_CONTAINER_H
+#define INC_6502_EMULATOR_JUMP_OPCODE_HANDLER_CONTAINER_H
+
+#include "opcode-handler-container.h"
+
+namespace emu_6502 {
+    class JumpOpcodeHandlerContainer : public OpcodeHandlerContainer {
+    private:
+        enum Op {
+            JMP_ABS = 0x4C,
+            JMP_IND = 0x6C,
+
+            JSR = 0x20,
+
+            RTI = 0x40,
+            RTS = 0x60
+        };
+
+        void jmp_abs(Machine& machine);
+        void jmp_ind(Machine& machine);
+
+        void jsr(Machine& machine);
+
+        void rti(Machine& machine);
+        void rts(Machine& machine);
+
+    public:
+        JumpOpcodeHandlerContainer();
+        JumpOpcodeHandlerContainer(const JumpOpcodeHandlerContainer&) = delete;
+        JumpOpcodeHandlerContainer& operator=(const JumpOpcodeHandlerContainer&) = delete;
+    };
+}
+
+
+#endif //INC_6502_EMULATOR_JUMP_OPCODE_HANDLER_CONTAINER_H

src/opcode/opcode-handler-directory.cpp

@@ -8,6 +8,7 @@
 #include "handler/compare-opcode-handler-container.h"
 #include "handler/stack-opcode-handler-container.h"
 #include "handler/branch-opcode-handler-container.h"
+#include "handler/jump-opcode-handler-container.h"
 #include "../utils.h"
 
 namespace emu_6502 {
@@ -22,6 +23,7 @@ namespace emu_6502 {
         handler_containers.push_back(make_unique<CompareOpcodeHandlerContainer>());
         handler_containers.push_back(make_unique<StackOpcodeHandlerContainer>());
         handler_containers.push_back(make_unique<BranchOpcodeHandlerContainer>());
+        handler_containers.push_back(make_unique<JumpOpcodeHandlerContainer>());
 
         init_handlers();
     }

src/utils.cpp

@@ -48,6 +48,18 @@ namespace emu_6502 {
         return address;
     }
 
+    uint16_t get_ind_address(Machine& machine) {
+        auto low_byte = machine.read_program_byte();
+        auto high_byte = machine.read_program_byte();
+        uint16_t paddress = (high_byte << 8) + low_byte;
+
+        auto low = machine.get_memory().get_at(paddress);
+        auto high = machine.get_memory().get_at(paddress + 1);
+        uint16_t address = (high << 8) + low;
+
+        return address;
+    }
+
     uint16_t get_ind_x_address(Machine& machine) {
         uint8_t paddress = machine.get_cpu().get_x().get_value() + machine.read_program_byte();
         auto low = machine.get_memory().get_at(paddress);

src/utils.h

@@ -15,11 +15,12 @@ namespace emu_6502 {
     uint8_t get_zpg_address(Machine& machine);
     uint8_t get_zpg_x_address(Machine& machine);
     uint8_t get_zpg_y_address(Machine& machine);
+
     uint16_t get_abs_address(Machine& machine);
     uint16_t get_abs_x_address(Machine& machine);
     uint16_t get_abs_y_address(Machine& machine);
-    uint16_t get_abs_x_address(Machine& machine);
-    uint16_t get_abs_y_address(Machine& machine);
+
+    uint16_t get_ind_address(Machine& machine);
     uint16_t get_ind_x_address(Machine& machine);
     uint16_t get_ind_y_address(Machine& machine);
 }

test/jump-opcode-handler-test.cpp

@@ -0,0 +1,66 @@
+#include "gtest/gtest.h"
+#include "test-utils.h"
+
+using namespace std;
+using namespace emu_6502;
+
+const uint8_t JMP_ABS = 0x4C;
+const uint8_t JMP_IND = 0x6C;
+
+const uint8_t JSR = 0x20;
+
+const uint8_t RTI = 0x40;
+const uint8_t RTS = 0x60;
+
+const uint8_t LDA_IMM = 0xA9;
+
+TEST(LoadOpcodeHandlerContainer, JMP_ABS) {
+    auto machine = create_machine({JMP_ABS, 0x34, 0x12});
+
+    try {
+        machine->execute();
+    }
+    catch (exception) {
+    }
+
+    ASSERT_EQ(0x1234, machine->get_cpu().get_pc().get_value());
+}
+
+TEST(LoadOpcodeHandlerContainer, JMP_IND) {
+    auto machine = create_machine({JMP_IND, 0x34, 0x12});
+    machine->get_memory().set_at(0x1234, 0xF6);
+    machine->get_memory().set_at(0x1235, 0xAB);
+    try {
+        machine->execute();
+    }
+    catch (exception) {
+    }
+
+    ASSERT_EQ(0xABF6, machine->get_cpu().get_pc().get_value());
+}
+
+TEST(LoadOpcodeHandlerContainer, JSR) {
+    auto machine = create_machine({JSR, 0x34, 0x12});
+
+    try {
+        machine->execute();
+    }
+    catch (exception) {
+    }
+
+    ASSERT_EQ(0x1234, machine->get_cpu().get_pc().get_value());
+    ASSERT_EQ(3, machine->get_stack().pop());
+}
+
+TEST(LoadOpcodeHandlerContainer, RTS) {
+    auto machine = create_machine({JSR, 0x07, 0x06, 0x0, 0x0, 0x0, 0x0, LDA_IMM, 0x99, RTS});
+
+    try {
+        machine->execute();
+    }
+    catch (exception) {
+    }
+
+    ASSERT_EQ(0x99, machine->get_cpu().get_a().get_value());
+    ASSERT_EQ(0x605, machine->get_cpu().get_pc().get_value());
+}