From e5c0d28fdccc9d968a64c5be7e643229545673b4 Mon Sep 17 00:00:00 2001
From: Connor McLaughlin <mclaughc@outlook.com>
Date: Fri, 22 Nov 2019 00:51:16 +1000
Subject: [PATCH] CPU/Recompiler: Implement mfhi/mthi/mflo/mtlo

---
 src/core/cpu_core.cpp                      |  4 ---
 src/core/cpu_recompiler_code_generator.cpp | 39 ++++++++++++++++++++++
 src/core/cpu_recompiler_code_generator.h   |  1 +
 src/core/cpu_types.cpp                     |  6 ++--
 4 files changed, 43 insertions(+), 7 deletions(-)

diff --git a/src/core/cpu_core.cpp b/src/core/cpu_core.cpp
index 50b404e88..d51f110fc 100644
--- a/src/core/cpu_core.cpp
+++ b/src/core/cpu_core.cpp
@@ -74,10 +74,6 @@ bool Core::DoState(StateWrapper& sw)
   sw.Do(&m_pending_ticks);
   sw.Do(&m_downcount);
   sw.DoArray(m_regs.r, countof(m_regs.r));
-  sw.Do(&m_regs.pc);
-  sw.Do(&m_regs.hi);
-  sw.Do(&m_regs.lo);
-  sw.Do(&m_regs.npc);
   sw.Do(&m_cop0_regs.BPC);
   sw.Do(&m_cop0_regs.BDA);
   sw.Do(&m_cop0_regs.TAR);
diff --git a/src/core/cpu_recompiler_code_generator.cpp b/src/core/cpu_recompiler_code_generator.cpp
index fc84d8e34..00fa0df15 100644
--- a/src/core/cpu_recompiler_code_generator.cpp
+++ b/src/core/cpu_recompiler_code_generator.cpp
@@ -114,6 +114,13 @@ bool CodeGenerator::CompileInstruction(const CodeBlockInstruction& cbi)
           result = Compile_ShiftVariable(cbi);
           break;
 
+        case InstructionFunct::mfhi:
+        case InstructionFunct::mflo:
+        case InstructionFunct::mthi:
+        case InstructionFunct::mtlo:
+          result = Compile_MoveHiLo(cbi);
+          break;
+
         default:
           result = Compile_Fallback(cbi);
           break;
@@ -873,6 +880,37 @@ bool CodeGenerator::Compile_Store(const CodeBlockInstruction& cbi)
   return true;
 }
 
+bool CodeGenerator::Compile_MoveHiLo(const CodeBlockInstruction& cbi)
+{
+  InstructionPrologue(cbi, 1);
+
+  switch (cbi.instruction.r.funct)
+  {
+    case InstructionFunct::mfhi:
+      m_register_cache.WriteGuestRegister(cbi.instruction.r.rd, m_register_cache.ReadGuestRegister(Reg::hi));
+      break;
+
+    case InstructionFunct::mthi:
+      m_register_cache.WriteGuestRegister(Reg::hi, m_register_cache.ReadGuestRegister(cbi.instruction.r.rs));
+      break;
+
+    case InstructionFunct::mflo:
+      m_register_cache.WriteGuestRegister(cbi.instruction.r.rd, m_register_cache.ReadGuestRegister(Reg::lo));
+      break;
+
+    case InstructionFunct::mtlo:
+      m_register_cache.WriteGuestRegister(Reg::lo, m_register_cache.ReadGuestRegister(cbi.instruction.r.rs));
+      break;
+
+    default:
+      UnreachableCode();
+      break;
+  }
+
+  InstructionEpilogue(cbi);
+  return true;
+}
+
 bool CodeGenerator::Compile_lui(const CodeBlockInstruction& cbi)
 {
   InstructionPrologue(cbi, 1);
@@ -897,4 +935,5 @@ bool CodeGenerator::Compile_addiu(const CodeBlockInstruction& cbi)
   InstructionEpilogue(cbi);
   return true;
 }
+
 } // namespace CPU::Recompiler
diff --git a/src/core/cpu_recompiler_code_generator.h b/src/core/cpu_recompiler_code_generator.h
index 3363be1ab..ed1497706 100644
--- a/src/core/cpu_recompiler_code_generator.h
+++ b/src/core/cpu_recompiler_code_generator.h
@@ -169,6 +169,7 @@ private:
   bool Compile_ShiftVariable(const CodeBlockInstruction& cbi);
   bool Compile_Load(const CodeBlockInstruction& cbi);
   bool Compile_Store(const CodeBlockInstruction& cbi);
+  bool Compile_MoveHiLo(const CodeBlockInstruction& cbi);
   bool Compile_lui(const CodeBlockInstruction& cbi);
   bool Compile_addiu(const CodeBlockInstruction& cbi);
 
diff --git a/src/core/cpu_types.cpp b/src/core/cpu_types.cpp
index 57d651c77..5c52f9e08 100644
--- a/src/core/cpu_types.cpp
+++ b/src/core/cpu_types.cpp
@@ -3,9 +3,9 @@
 #include <array>
 
 namespace CPU {
-static const std::array<const char*, 32> s_reg_names = {
-  {"$zero", "at", "v0", "v1", "a0", "a1", "a2", "a3", "t0", "t1", "t2", "t3", "t4", "t5", "t6", "t7",
-   "s0",    "s1", "s2", "s3", "s4", "s5", "s6", "s7", "t8", "t9", "k0", "k1", "gp", "sp", "fp", "ra"}};
+static const std::array<const char*, 36> s_reg_names = {
+  {"$zero", "at", "v0", "v1", "a0", "a1", "a2", "a3", "t0", "t1", "t2", "t3", "t4", "t5", "t6", "t7", "s0", "s1",
+   "s2",    "s3", "s4", "s5", "s6", "s7", "t8", "t9", "k0", "k1", "gp", "sp", "fp", "ra", "hi", "lo", "pc", "npc"}};
 
 const char* GetRegName(Reg reg)
 {