diff --git a/src/dynarmic/src/dynarmic/backend/arm64/reg_alloc.cpp b/src/dynarmic/src/dynarmic/backend/arm64/reg_alloc.cpp
index 3b55fa2eff..52b4cf1696 100644
--- a/src/dynarmic/src/dynarmic/backend/arm64/reg_alloc.cpp
+++ b/src/dynarmic/src/dynarmic/backend/arm64/reg_alloc.cpp
@@ -144,7 +144,7 @@ RegAlloc::ArgumentInfo RegAlloc::GetArgumentInfo(IR::Inst* inst) {
 }
 
 bool RegAlloc::WasValueDefined(IR::Inst* inst) const {
-    return defined_insts_count > 0;
+    return defined_insts.count(inst) > 0;
 }
 
 void RegAlloc::PrepareForCall(std::optional<Argument::copyable_reference> arg0, std::optional<Argument::copyable_reference> arg1, std::optional<Argument::copyable_reference> arg2, std::optional<Argument::copyable_reference> arg3) {
@@ -192,8 +192,7 @@ void RegAlloc::PrepareForCall(std::optional<Argument::copyable_reference> arg0,
 }
 
 void RegAlloc::DefineAsExisting(IR::Inst* inst, Argument& arg) {
-    ++defined_insts_count;
-
+    defined_insts.insert(inst);
     ASSERT(!ValueLocation(inst));
 
     if (arg.value.IsImmediate()) {
@@ -207,8 +206,7 @@ void RegAlloc::DefineAsExisting(IR::Inst* inst, Argument& arg) {
 }
 
 void RegAlloc::DefineAsRegister(IR::Inst* inst, oaknut::Reg reg) {
-    ++defined_insts_count;
-
+    defined_insts.insert(inst);
     ASSERT(!ValueLocation(inst));
     auto& info = reg.is_vector() ? fprs[reg.index()] : gprs[reg.index()];
     ASSERT(info.IsCompletelyEmpty());
@@ -374,8 +372,7 @@ int RegAlloc::RealizeReadImpl(const IR::Value& value) {
 
 template<HostLoc::Kind kind>
 int RegAlloc::RealizeWriteImpl(const IR::Inst* value) {
-    ++defined_insts_count;
-
+    defined_insts.insert(inst);
     ASSERT(!ValueLocation(value));
 
     if constexpr (kind == HostLoc::Kind::Gpr) {
@@ -399,8 +396,7 @@ int RegAlloc::RealizeWriteImpl(const IR::Inst* value) {
 
 template<HostLoc::Kind kind>
 int RegAlloc::RealizeReadWriteImpl(const IR::Value& read_value, const IR::Inst* write_value) {
-    ++defined_insts_count;
-
+    defined_insts.insert(inst);
     // TODO: Move elimination
 
     const int write_loc = RealizeWriteImpl<kind>(write_value);
@@ -463,8 +459,7 @@ void RegAlloc::SpillFpr(int index) {
 }
 
 void RegAlloc::ReadWriteFlags(Argument& read, IR::Inst* write) {
-    ++defined_insts_count;
-
+    defined_insts.insert(inst);
     const auto current_location = ValueLocation(read.value.GetInst());
     ASSERT(current_location);
 
diff --git a/src/dynarmic/src/dynarmic/backend/arm64/reg_alloc.h b/src/dynarmic/src/dynarmic/backend/arm64/reg_alloc.h
index ea47f1c897..ee93f13cfc 100644
--- a/src/dynarmic/src/dynarmic/backend/arm64/reg_alloc.h
+++ b/src/dynarmic/src/dynarmic/backend/arm64/reg_alloc.h
@@ -332,8 +332,7 @@ private:
     std::array<HostLocInfo, SpillCount> spills;
 
     mutable std::mt19937 rand_gen;
-
-    size_t defined_insts_count = 0;
+    ankerl::unordered_dense::set<const IR::Inst*> defined_insts;
 };
 
 template<typename T>