Merge pull request #10818 from Pokechu22/icache-always-invalidate

PPCCache: Always invalidate on icbi, even if icache is disabled

Source/Core/Core/PowerPC/PPCCache.cpp

@@ -419,11 +419,13 @@ void InstructionCache::Invalidate(u32 addr)
 {
   auto& system = Core::System::GetInstance();
   auto& memory = system.GetMemory();
-  auto& ppc_state = system.GetPPCState();
-  if (!HID0(ppc_state).ICE || m_disable_icache)
-    return;
 
-  // Invalidates the whole set
+  // Per the 750cl manual, section 3.4.1.5 Instruction Cache Enabling/Disabling (page 137)
+  // and section 3.4.2.6 Instruction Cache Block Invalidate (icbi) (page 140), the icbi
+  // instruction always invalidates, even if the instruction cache is disabled or locked,
+  // and it also invalidates all ways of the corresponding cache set, not just the way corresponding
+  // to the given address.
+  // (However, the icbi instruction's info on page 432 does not include this information)
   const u32 set = (addr >> 5) & 0x7f;
   for (size_t way = 0; way < 8; way++)
   {
@@ -440,6 +442,7 @@ void InstructionCache::Invalidate(u32 addr)
   valid[set] = 0;
   modified[set] = 0;
 
+  // Also tell the JIT that the corresponding address has been invalidated
   system.GetJitInterface().InvalidateICacheLine(addr);
 }