LLVM: Implement Recursive Intrinsics

rpcs3/Emu/CPU/CPUTranslator.cpp

@@ -371,23 +371,69 @@ void cpu_translator::replace_intrinsics(llvm::Function& f)
 {
 	for (auto& bb : f)
 	{
-		for (auto bit = bb.begin(); bit != bb.end();)
+		std::set<std::string_view> names;
+
+		using InstListType = llvm::BasicBlock::InstListType;
+
+		std::function<InstListType::iterator(InstListType::iterator)> fix_funcs;
+
+		fix_funcs = [&](InstListType::iterator inst_bit)
 		{
-			if (auto ci = llvm::dyn_cast<llvm::CallInst>(&*bit))
+			auto ci = llvm::dyn_cast<llvm::CallInst>(&*inst_bit);
+
+			if (!ci)
 			{
-				if (auto cf = ci->getCalledFunction())
-				{
-					if (auto it = m_intrinsics.find(std::string_view(cf->getName().data(), cf->getName().size())); it != m_intrinsics.end())
-					{
-						m_ir->SetInsertPoint(ci);
-						ci->replaceAllUsesWith(it->second(ci));
-						bit = ci->eraseFromParent();
-						continue;
+				return std::next(inst_bit);
 			}
+
+			const auto cf = ci->getCalledFunction();
+
+			if (!cf)
+			{
+				return std::next(inst_bit);
+			}
+
+			std::string_view func_name{cf->getName().data(), cf->getName().size()};
+
+			const auto it = m_intrinsics.find(func_name);
+
+			if (it == m_intrinsics.end())
+			{
+				return std::next(inst_bit);
+			}
+
+			if (names.contains(func_name))
+			{
+				fmt::throw_exception("cpu_translator::replace_intrinsics(): Recursion detected at function '%s'!", func_name);
+			}
+
+			names.emplace(func_name);
+
+			m_ir->SetInsertPoint(ci);
+			auto result = it->second(ci);
+			auto end = m_ir->GetInsertPoint();
+
+			inst_bit->replaceAllUsesWith(result);
+			const auto next_it = inst_bit->eraseFromParent();
+
+			for (auto inner = ci->getNextNode(); inner && InstListType::iterator(inner) != end;)
+			{
+				if (auto it_ci = llvm::dyn_cast<llvm::CallInst>(&*inner))
+				{
+					fix_funcs(InstListType::iterator(inner));
+				}
+				else
+				{
+					inner = inner->getNextNode();
 				}
 			}
 
-			++bit;
+			ensure(names.erase(func_name));
+			return next_it;
+		};
+
+		for (auto bit = bb.begin(); bit != bb.end(); bit = fix_funcs(bit))
+		{
 		}
 	}
 }