Jit64: Recompile asm routines on cache clear

This is needed so that the checks added in the previous commit will be
reevaluated if the value of m_enable_dcache changes.

JitArm64 was already recompiling its asm routines on cache clear by
necessity. It doesn't have the same setup as Jit64 where the asm
routines are in a separate region, so clearing the JitArm64 cache
results in the asm routines being cleared too.

Source/Core/Core/PowerPC/Jit64/Jit.cpp

@@ -305,6 +305,7 @@ void Jit64::ClearCache()
   ClearCodeSpace();
   Clear();
   RefreshConfig(InitFastmemArena::No);
+  asm_routines.Regenerate();
   ResetFreeMemoryRanges();
 }
 

Source/Core/Core/PowerPC/Jit64/JitAsm.cpp

@@ -32,7 +32,15 @@ void Jit64AsmRoutineManager::Init()
 {
   m_const_pool.Init(AllocChildCodeSpace(4096), 4096);
   Generate();
-  WriteProtect();
+  WriteProtect(true);
+}
+
+void Jit64AsmRoutineManager::Regenerate()
+{
+  UnWriteProtect(false);
+  ResetCodePtr();
+  Generate();
+  WriteProtect(true);
 }
 
 // PLAN: no more block numbers - crazy opcodes just contain offset within

Source/Core/Core/PowerPC/Jit64/JitAsm.h

@@ -35,6 +35,7 @@ public:
   explicit Jit64AsmRoutineManager(Jit64& jit);
 
   void Init();
+  void Regenerate();
 
   void ResetStack(Gen::X64CodeBlock& emitter);