CPU: Make fastmem a compile-time feature (support 32-bit targets)

src/core/CMakeLists.txt

@@ -115,13 +115,13 @@ endif()
 
 if(${CPU_ARCH} STREQUAL "x64")
   target_include_directories(core PRIVATE "${CMAKE_CURRENT_SOURCE_DIR}/../../dep/xbyak/xbyak")
-  target_compile_definitions(core PRIVATE "WITH_RECOMPILER=1")
+  target_compile_definitions(core PRIVATE "WITH_RECOMPILER=1 WITH_FASTMEM=1")
   target_sources(core PRIVATE ${RECOMPILER_SRCS}
     cpu_recompiler_code_generator_x64.cpp
   )
   message("Building x64 recompiler")
 elseif(${CPU_ARCH} STREQUAL "aarch64")
-  target_compile_definitions(core PRIVATE "WITH_RECOMPILER=1")
+  target_compile_definitions(core PRIVATE "WITH_RECOMPILER=1 WITH_FASTMEM=1")
   target_sources(core PRIVATE ${RECOMPILER_SRCS}
     cpu_recompiler_code_generator_aarch64.cpp
   )

src/core/bus.cpp

@@ -87,15 +87,21 @@ static u32 m_ram_size_reg = 0;
 static std::string m_tty_line_buffer;
 
 static Common::MemoryArena m_memory_arena;
+
+#ifdef WITH_FASTMEM
 static u8* m_fastmem_base = nullptr;
 static std::vector<Common::MemoryArena::View> m_fastmem_ram_views;
+#endif
 
 static std::tuple<TickCount, TickCount, TickCount> CalculateMemoryTiming(MEMDELAY mem_delay, COMDELAY common_delay);
 static void RecalculateMemoryTimings();
 
-static void SetCodePageFastmemProtection(u32 page_index, bool writable);
 static bool AllocateMemory();
+
+#ifdef WITH_FASTMEM
+static void SetCodePageFastmemProtection(u32 page_index, bool writable);
 static void UnmapFastmemViews();
+#endif
 
 #define FIXUP_WORD_READ_OFFSET(offset) ((offset) & ~u32(3))
 #define FIXUP_WORD_READ_VALUE(offset, value) ((value) >> (((offset)&u32(3)) * 8u))
@@ -126,7 +132,10 @@ bool Initialize()
 
 void Shutdown()
 {
+#ifdef WITH_FASTMEM
   UnmapFastmemViews();
+#endif
+
   if (g_ram)
   {
     m_memory_arena.ReleaseViewPtr(g_ram, RAM_SIZE);
@@ -259,6 +268,8 @@ bool AllocateMemory()
   return true;
 }
 
+#ifdef WITH_FASTMEM
+
 void UnmapFastmemViews()
 {
   m_fastmem_ram_views.clear();
@@ -344,6 +355,8 @@ bool CanUseFastmemForAddress(VirtualMemoryAddress address)
   return (paddr < RAM_SIZE);
 }
 
+#endif
+
 bool IsRAMCodePage(u32 index)
 {
   return m_ram_code_bits[index];
@@ -356,7 +369,10 @@ void SetRAMCodePage(u32 index)
 
   // protect fastmem pages
   m_ram_code_bits[index] = true;
+
+#ifdef WITH_FASTMEM
   SetCodePageFastmemProtection(index, false);
+#endif
 }
 
 void ClearRAMCodePage(u32 index)
@@ -366,9 +382,14 @@ void ClearRAMCodePage(u32 index)
 
   // unprotect fastmem pages
   m_ram_code_bits[index] = false;
+
+#ifdef WITH_FASTMEM
   SetCodePageFastmemProtection(index, true);
+#endif
 }
 
+#ifdef WITH_FASTMEM
+
 void SetCodePageFastmemProtection(u32 page_index, bool writable)
 {
   // unprotect fastmem pages
@@ -383,10 +404,13 @@ void SetCodePageFastmemProtection(u32 page_index, bool writable)
   }
 }
 
+#endif
+
 void ClearRAMCodePageFlags()
 {
   m_ram_code_bits.reset();
 
+#ifdef WITH_FASTMEM
   // unprotect fastmem pages
   for (const auto& view : m_fastmem_ram_views)
   {
@@ -395,6 +419,7 @@ void ClearRAMCodePageFlags()
       Log_ErrorPrintf("Failed to unprotect code pages for fastmem view @ %p", view.GetBasePointer());
     }
   }
+#endif
 }
 
 bool IsCodePageAddress(PhysicalMemoryAddress address)

src/core/bus.h

@@ -82,8 +82,10 @@ enum : size_t
   // Offsets within the memory arena.
   MEMORY_ARENA_RAM_OFFSET = 0,
 
+#ifdef WITH_FASTMEM
   // Fastmem region size is 4GB to cover the entire 32-bit address space.
   FASTMEM_REGION_SIZE = UINT64_C(0x100000000)
+#endif
 };
 
 bool Initialize();
@@ -91,9 +93,10 @@ void Shutdown();
 void Reset();
 bool DoState(StateWrapper& sw);
 
-u8* GetFastmemBase();
+#ifdef WITH_FASTMEM
 void UpdateFastmemViews(bool enabled, bool isolate_cache);
 bool CanUseFastmemForAddress(VirtualMemoryAddress address);
+#endif
 
 void SetExpansionROM(std::vector<u8> data);
 void SetBIOS(const std::vector<u8>& image);

src/core/core.vcxproj

@@ -425,7 +425,7 @@
       </PrecompiledHeader>
       <WarningLevel>Level4</WarningLevel>
       <Optimization>Disabled</Optimization>
-      <PreprocessorDefinitions>WITH_IMGUI=1;WITH_RECOMPILER=1;_CRT_SECURE_NO_WARNINGS;WIN32;_DEBUG;_CONSOLE;_LIB;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WITH_IMGUI=1;WITH_RECOMPILER=1;WITH_FASTMEM=1;_CRT_SECURE_NO_WARNINGS;WIN32;_DEBUG;_CONSOLE;_LIB;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <SDLCheck>true</SDLCheck>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <AdditionalIncludeDirectories>$(SolutionDir)dep\msvc\include;$(SolutionDir)dep\glad\include;$(SolutionDir)dep\stb\include;$(SolutionDir)dep\imgui\include;$(SolutionDir)dep\xbyak\xbyak;$(SolutionDir)dep\zlib\include;$(SolutionDir)dep\vulkan-loader\include;$(SolutionDir)src;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
@@ -451,7 +451,7 @@
       </PrecompiledHeader>
       <WarningLevel>Level4</WarningLevel>
       <Optimization>Disabled</Optimization>
-      <PreprocessorDefinitions>WITH_IMGUI=1;WITH_RECOMPILER=1;_CRT_SECURE_NO_WARNINGS;WIN32;_DEBUG;_CONSOLE;_LIB;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WITH_IMGUI=1;WITH_RECOMPILER=1;WITH_FASTMEM=1;_CRT_SECURE_NO_WARNINGS;WIN32;_DEBUG;_CONSOLE;_LIB;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <SDLCheck>true</SDLCheck>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <AdditionalIncludeDirectories>$(SolutionDir)dep\msvc\include;$(SolutionDir)dep\glad\include;$(SolutionDir)dep\stb\include;$(SolutionDir)dep\imgui\include;$(SolutionDir)dep\vixl\include;$(SolutionDir)dep\zlib\include;$(SolutionDir)dep\vulkan-loader\include;$(SolutionDir)src;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
@@ -506,7 +506,7 @@
       </PrecompiledHeader>
       <WarningLevel>Level4</WarningLevel>
       <Optimization>Disabled</Optimization>
-      <PreprocessorDefinitions>WITH_IMGUI=1;WITH_RECOMPILER=1;_ITERATOR_DEBUG_LEVEL=1;_CRT_SECURE_NO_WARNINGS;WIN32;_DEBUGFAST;_DEBUG;_CONSOLE;_LIB;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WITH_IMGUI=1;WITH_RECOMPILER=1;WITH_FASTMEM=1;_ITERATOR_DEBUG_LEVEL=1;_CRT_SECURE_NO_WARNINGS;WIN32;_DEBUGFAST;_DEBUG;_CONSOLE;_LIB;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <SDLCheck>true</SDLCheck>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <AdditionalIncludeDirectories>$(SolutionDir)dep\msvc\include;$(SolutionDir)dep\glad\include;$(SolutionDir)dep\stb\include;$(SolutionDir)dep\imgui\include;$(SolutionDir)dep\xbyak\xbyak;$(SolutionDir)dep\zlib\include;$(SolutionDir)dep\vulkan-loader\include;$(SolutionDir)src;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
@@ -535,7 +535,7 @@
       </PrecompiledHeader>
       <WarningLevel>Level4</WarningLevel>
       <Optimization>Disabled</Optimization>
-      <PreprocessorDefinitions>WITH_IMGUI=1;WITH_RECOMPILER=1;_ITERATOR_DEBUG_LEVEL=1;_CRT_SECURE_NO_WARNINGS;WIN32;_DEBUGFAST;_DEBUG;_CONSOLE;_LIB;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WITH_IMGUI=1;WITH_RECOMPILER=1;WITH_FASTMEM=1;_ITERATOR_DEBUG_LEVEL=1;_CRT_SECURE_NO_WARNINGS;WIN32;_DEBUGFAST;_DEBUG;_CONSOLE;_LIB;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <SDLCheck>true</SDLCheck>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <AdditionalIncludeDirectories>$(SolutionDir)dep\msvc\include;$(SolutionDir)dep\glad\include;$(SolutionDir)dep\stb\include;$(SolutionDir)dep\imgui\include;$(SolutionDir)dep\vixl\include;$(SolutionDir)dep\zlib\include;$(SolutionDir)dep\vulkan-loader\include;$(SolutionDir)src;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
@@ -620,7 +620,7 @@
       </PrecompiledHeader>
       <Optimization>MaxSpeed</Optimization>
       <IntrinsicFunctions>true</IntrinsicFunctions>
-      <PreprocessorDefinitions>WITH_IMGUI=1;WITH_RECOMPILER=1;_CRT_SECURE_NO_WARNINGS;WIN32;NDEBUG;_CONSOLE;_LIB;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WITH_IMGUI=1;WITH_RECOMPILER=1;WITH_FASTMEM=1;_CRT_SECURE_NO_WARNINGS;WIN32;NDEBUG;_CONSOLE;_LIB;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalIncludeDirectories>$(SolutionDir)dep\msvc\include;$(SolutionDir)dep\glad\include;$(SolutionDir)dep\stb\include;$(SolutionDir)dep\imgui\include;$(SolutionDir)dep\xbyak\xbyak;$(SolutionDir)dep\zlib\include;$(SolutionDir)dep\vulkan-loader\include;$(SolutionDir)src;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <MultiProcessorCompilation>true</MultiProcessorCompilation>
       <WholeProgramOptimization>false</WholeProgramOptimization>
@@ -647,7 +647,7 @@
       </PrecompiledHeader>
       <Optimization>MaxSpeed</Optimization>
       <IntrinsicFunctions>true</IntrinsicFunctions>
-      <PreprocessorDefinitions>WITH_IMGUI=1;WITH_RECOMPILER=1;_CRT_SECURE_NO_WARNINGS;WIN32;NDEBUG;_CONSOLE;_LIB;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WITH_IMGUI=1;WITH_RECOMPILER=1;WITH_FASTMEM=1;_CRT_SECURE_NO_WARNINGS;WIN32;NDEBUG;_CONSOLE;_LIB;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalIncludeDirectories>$(SolutionDir)dep\msvc\include;$(SolutionDir)dep\glad\include;$(SolutionDir)dep\stb\include;$(SolutionDir)dep\imgui\include;$(SolutionDir)dep\vixl\include;$(SolutionDir)dep\zlib\include;$(SolutionDir)dep\vulkan-loader\include;$(SolutionDir)src;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <MultiProcessorCompilation>true</MultiProcessorCompilation>
       <WholeProgramOptimization>false</WholeProgramOptimization>
@@ -674,7 +674,7 @@
       </PrecompiledHeader>
       <Optimization>MaxSpeed</Optimization>
       <IntrinsicFunctions>true</IntrinsicFunctions>
-      <PreprocessorDefinitions>WITH_IMGUI=1;WITH_RECOMPILER=1;_CRT_SECURE_NO_WARNINGS;WIN32;NDEBUG;_CONSOLE;_LIB;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WITH_IMGUI=1;WITH_RECOMPILER=1;WITH_FASTMEM=1;_CRT_SECURE_NO_WARNINGS;WIN32;NDEBUG;_CONSOLE;_LIB;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalIncludeDirectories>$(SolutionDir)dep\msvc\include;$(SolutionDir)dep\glad\include;$(SolutionDir)dep\stb\include;$(SolutionDir)dep\imgui\include;$(SolutionDir)dep\xbyak\xbyak;$(SolutionDir)dep\zlib\include;$(SolutionDir)dep\vulkan-loader\include;$(SolutionDir)src;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <MultiProcessorCompilation>true</MultiProcessorCompilation>
       <WholeProgramOptimization>true</WholeProgramOptimization>
@@ -702,7 +702,7 @@
       </PrecompiledHeader>
       <Optimization>MaxSpeed</Optimization>
       <IntrinsicFunctions>true</IntrinsicFunctions>
-      <PreprocessorDefinitions>WITH_IMGUI=1;WITH_RECOMPILER=1;_CRT_SECURE_NO_WARNINGS;WIN32;NDEBUG;_CONSOLE;_LIB;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WITH_IMGUI=1;WITH_RECOMPILER=1;WITH_FASTMEM=1;_CRT_SECURE_NO_WARNINGS;WIN32;NDEBUG;_CONSOLE;_LIB;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalIncludeDirectories>$(SolutionDir)dep\msvc\include;$(SolutionDir)dep\glad\include;$(SolutionDir)dep\stb\include;$(SolutionDir)dep\imgui\include;$(SolutionDir)dep\vixl\include;$(SolutionDir)dep\zlib\include;$(SolutionDir)dep\vulkan-loader\include;$(SolutionDir)src;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <MultiProcessorCompilation>true</MultiProcessorCompilation>
       <WholeProgramOptimization>true</WholeProgramOptimization>

src/core/cpu_code_cache.cpp

@@ -99,10 +99,13 @@ static HostCodeMap s_host_code_map;
 
 static void AddBlockToHostCodeMap(CodeBlock* block);
 static void RemoveBlockFromHostCodeMap(CodeBlock* block);
+
+#ifdef WITH_FASTMEM
 static bool InitializeFastmem();
 static void ShutdownFastmem();
 static Common::PageFaultHandler::HandlerResult PageFaultHandler(void* exception_pc, void* fault_address, bool is_write);
-#endif
+#endif // WITH_FASTMEM
+#endif // WITH_RECOMPILER
 
 void Initialize()
 {
@@ -121,8 +124,10 @@ void Initialize()
       Panic("Failed to initialize code space");
     }
 
+#ifdef WITH_FASTMEM
     if (g_settings.IsUsingFastmem() && !InitializeFastmem())
       Panic("Failed to initialize fastmem");
+#endif
 
     ResetFastMap();
     CompileDispatcher();
@@ -150,7 +155,9 @@ void ClearState()
 void Shutdown()
 {
   ClearState();
+#ifdef WITH_FASTMEM
   ShutdownFastmem();
+#endif
 #ifdef WITH_RECOMPILER
   s_code_buffer.Destroy();
 #endif
@@ -326,7 +333,10 @@ void Reinitialize()
 
 #ifdef WITH_RECOMPILER
 
+#ifdef WITH_FASTMEM
   ShutdownFastmem();
+#endif
+
   s_code_buffer.Destroy();
 
   if (g_settings.IsUsingRecompiler())
@@ -342,8 +352,10 @@ void Reinitialize()
       Panic("Failed to initialize code space");
     }
 
+#ifdef WITH_FASTMEM
     if (g_settings.IsUsingFastmem() && !InitializeFastmem())
       Panic("Failed to initialize fastmem");
+#endif
 
     ResetFastMap();
     CompileDispatcher();
@@ -354,8 +366,10 @@ void Reinitialize()
 void Flush()
 {
   ClearState();
+#ifdef WITH_RECOMPILER
   if (g_settings.IsUsingRecompiler())
     CompileDispatcher();
+#endif
 }
 
 void LogCurrentState()
@@ -437,7 +451,9 @@ bool RevalidateBlock(CodeBlock* block)
   return true;
 
 recompile:
+#ifdef WITH_RECOMPILER
   RemoveBlockFromHostCodeMap(block);
+#endif
 
   block->instructions.clear();
   if (!CompileBlock(block))
@@ -447,8 +463,10 @@ recompile:
     return false;
   }
 
+#ifdef WITH_RECOMPILER
   // re-add to page map again
   AddBlockToHostCodeMap(block);
+#endif
   if (block->IsInRAM())
     AddBlockToPageMap(block);
 
@@ -713,6 +731,8 @@ void RemoveBlockFromHostCodeMap(CodeBlock* block)
   s_host_code_map.erase(hc_iter);
 }
 
+#ifdef WITH_FASTMEM
+
 bool InitializeFastmem()
 {
   if (!Common::PageFaultHandler::InstallHandler(&s_host_code_map, PageFaultHandler))
@@ -801,6 +821,8 @@ Common::PageFaultHandler::HandlerResult PageFaultHandler(void* exception_pc, voi
   return Common::PageFaultHandler::HandlerResult::ExecuteNextHandler;
 }
 
-#endif
+#endif // WITH_FASTMEM
+
+#endif // WITH_RECOMPILER
 
 } // namespace CPU::CodeCache

src/core/cpu_core.cpp

@@ -1600,11 +1600,15 @@ bool InterpretInstructionPGXP()
   return g_state.exception_raised;
 }
 
+#ifdef WITH_FASTMEM
+
 void UpdateFastmemMapping()
 {
   Bus::UpdateFastmemViews(true, g_state.cop0_regs.sr.Isc);
 }
 
+#endif
+
 } // namespace Recompiler::Thunks
 
 } // namespace CPU

src/core/cpu_recompiler_code_generator.cpp

@@ -2202,6 +2202,7 @@ bool CodeGenerator::Compile_cop0(const CodeBlockInstruction& cbi)
               value = AndValues(value, Value::FromConstantU32(write_mask));
             }
 
+#ifdef WITH_FASTMEM
             // changing SR[Isc] needs to update fastmem views
             if (reg == Cop0Reg::SR && g_settings.cpu_fastmem)
             {
@@ -2211,13 +2212,18 @@ bool CodeGenerator::Compile_cop0(const CodeBlockInstruction& cbi)
               EmitStoreCPUStructField(offset, value);
               EmitXor(old_value.host_reg, old_value.host_reg, value);
               EmitBranchIfBitClear(old_value.host_reg, RegSize_32, 16, &skip_fastmem_update);
+              m_register_cache.InhibitAllocation();
               EmitFunctionCall(nullptr, &Thunks::UpdateFastmemMapping, m_register_cache.GetCPUPtr());
               EmitBindLabel(&skip_fastmem_update);
+              m_register_cache.UninhibitAllocation();
             }
             else
             {
               EmitStoreCPUStructField(offset, value);
             }
+#else
+            EmitStoreCPUStructField(offset, value);
+#endif
           }
         }
 

src/core/cpu_recompiler_code_generator.h

@@ -79,13 +79,17 @@ public:
   // Automatically generates an exception handler.
   Value EmitLoadGuestMemory(const CodeBlockInstruction& cbi, const Value& address, const SpeculativeValue& address_spec,
                             RegSize size);
+#ifdef WITH_FASTMEM
   void EmitLoadGuestRAMFastmem(const Value& address, RegSize size, Value& result);
   void EmitLoadGuestMemoryFastmem(const CodeBlockInstruction& cbi, const Value& address, RegSize size, Value& result);
+#endif
   void EmitLoadGuestMemorySlowmem(const CodeBlockInstruction& cbi, const Value& address, RegSize size, Value& result,
                                   bool in_far_code);
   void EmitStoreGuestMemory(const CodeBlockInstruction& cbi, const Value& address, const SpeculativeValue& address_spec,
                             const Value& value);
+#ifdef WITH_FASTMEM
   void EmitStoreGuestMemoryFastmem(const CodeBlockInstruction& cbi, const Value& address, const Value& value);
+#endif
   void EmitStoreGuestMemorySlowmem(const CodeBlockInstruction& cbi, const Value& address, const Value& value,
                                    bool in_far_code);
 

src/core/cpu_recompiler_code_generator_generic.cpp

@@ -41,6 +41,8 @@ Value CodeGenerator::EmitLoadGuestMemory(const CodeBlockInstruction& cbi, const
     {
       Value result = m_register_cache.AllocateScratch(size);
 
+#ifdef WITH_FASTMEM
+
       if (g_settings.IsUsingFastmem() && Bus::IsRAMAddress(static_cast<u32>(address.constant_value)))
       {
         // have to mask away the high bits for mirrors, since we don't map them in fastmem
@@ -52,6 +54,12 @@ Value CodeGenerator::EmitLoadGuestMemory(const CodeBlockInstruction& cbi, const
         EmitLoadGlobal(result.GetHostRegister(), size, ptr);
       }
 
+#else
+
+      EmitLoadGlobal(result.GetHostRegister(), size, ptr);
+
+#endif
+
       m_delayed_cycles_add += read_ticks;
       return result;
     }
@@ -59,6 +67,8 @@ Value CodeGenerator::EmitLoadGuestMemory(const CodeBlockInstruction& cbi, const
 
   AddPendingCycles(true);
 
+#ifdef WITH_FASTMEM
+
   const bool use_fastmem = address_spec ? Bus::CanUseFastmemForAddress(*address_spec) : true;
   if (address_spec)
   {
@@ -83,24 +93,35 @@ Value CodeGenerator::EmitLoadGuestMemory(const CodeBlockInstruction& cbi, const
     EmitLoadGuestMemorySlowmem(cbi, address, size, result, false);
   }
 
+#else
+
+  Value result = m_register_cache.AllocateScratch(HostPointerSize);
+  m_register_cache.FlushCallerSavedGuestRegisters(true, true);
+  EmitLoadGuestMemorySlowmem(cbi, address, size, result, false);
+
+#endif
+
   // Downcast to ignore upper 56/48/32 bits. This should be a noop.
-  switch (size)
+  if (result.size != size)
   {
-    case RegSize_8:
+    switch (size)
-      ConvertValueSizeInPlace(&result, RegSize_8, false);
+    {
-      break;
+      case RegSize_8:
+        ConvertValueSizeInPlace(&result, RegSize_8, false);
+        break;
 
-    case RegSize_16:
+      case RegSize_16:
-      ConvertValueSizeInPlace(&result, RegSize_16, false);
+        ConvertValueSizeInPlace(&result, RegSize_16, false);
-      break;
+        break;
 
-    case RegSize_32:
+      case RegSize_32:
-      ConvertValueSizeInPlace(&result, RegSize_32, false);
+        ConvertValueSizeInPlace(&result, RegSize_32, false);
-      break;
+        break;
 
-    default:
+      default:
-      UnreachableCode();
+        UnreachableCode();
-      break;
+        break;
+    }
   }
 
   return result;
@@ -124,6 +145,8 @@ void CodeGenerator::EmitStoreGuestMemory(const CodeBlockInstruction& cbi, const
 
   AddPendingCycles(true);
 
+#ifdef WITH_FASTMEM
+
   const bool use_fastmem = address_spec ? Bus::CanUseFastmemForAddress(*address_spec) : true;
   if (address_spec)
   {
@@ -146,6 +169,13 @@ void CodeGenerator::EmitStoreGuestMemory(const CodeBlockInstruction& cbi, const
     m_register_cache.FlushCallerSavedGuestRegisters(true, true);
     EmitStoreGuestMemorySlowmem(cbi, address, value, false);
   }
+
+#else
+
+  m_register_cache.FlushCallerSavedGuestRegisters(true, true);
+  EmitStoreGuestMemorySlowmem(cbi, address, value, false);
+
+#endif
 }
 
 #ifndef CPU_X64

src/core/cpu_recompiler_thunks.h

@@ -32,8 +32,12 @@ void UncheckedWriteMemoryByte(u32 address, u8 value);
 void UncheckedWriteMemoryHalfWord(u32 address, u16 value);
 void UncheckedWriteMemoryWord(u32 address, u32 value);
 
+#ifdef WITH_FASTMEM
+
 void UpdateFastmemMapping();
 
+#endif
+
 } // namespace Recompiler::Thunks
 
 } // namespace CPU