2 files changed, 38 insertions, 16 deletions

diff --git a/src/core/hle/kernel/kernel.cpp b/src/core/hle/kernel/kernel.cpp
index 8673384ee..8fdab44e4 100644
--- a/src/core/hle/kernel/kernel.cpp
+++ b/src/core/hle/kernel/kernel.cpp
@@ -261,20 +261,23 @@ struct KernelCore::Impl {
         current_process = process;
     }
 
-    /// Creates a new host thread ID, should only be called by GetHostThreadId
-    u32 AllocateHostThreadId(std::optional<std::size_t> core_id) {
-        if (core_id) {
-            // The first for slots are reserved for CPU core threads
-            ASSERT(*core_id < Core::Hardware::NUM_CPU_CORES);
-            return static_cast<u32>(*core_id);
-        } else {
-            return next_host_thread_id++;
+    static inline thread_local u32 host_thread_id = UINT32_MAX;
+
+    /// Gets the host thread ID for the caller, allocating a new one if this is the first time
+    u32 GetHostThreadId(std::size_t core_id) {
+        if (host_thread_id == UINT32_MAX) {
+            // The first four slots are reserved for CPU core threads
+            ASSERT(core_id < Core::Hardware::NUM_CPU_CORES);
+            host_thread_id = static_cast<u32>(core_id);
         }
+        return host_thread_id;
     }
 
     /// Gets the host thread ID for the caller, allocating a new one if this is the first time
-    u32 GetHostThreadId(std::optional<std::size_t> core_id = std::nullopt) {
-        const thread_local auto host_thread_id{AllocateHostThreadId(core_id)};
+    u32 GetHostThreadId() {
+        if (host_thread_id == UINT32_MAX) {
+            host_thread_id = next_host_thread_id++;
+        }
         return host_thread_id;
     }
 
diff --git a/src/core/hle/service/am/applets/applet_error.cpp b/src/core/hle/service/am/applets/applet_error.cpp
index ef6854d62..36a4aa9cd 100644
--- a/src/core/hle/service/am/applets/applet_error.cpp
+++ b/src/core/hle/service/am/applets/applet_error.cpp
@@ -16,6 +16,30 @@
 
 namespace Service::AM::Applets {
 
+struct ErrorCode {
+    u32 error_category{};
+    u32 error_number{};
+
+    static constexpr ErrorCode FromU64(u64 error_code) {
+        return {
+            .error_category{static_cast<u32>(error_code >> 32)},
+            .error_number{static_cast<u32>(error_code & 0xFFFFFFFF)},
+        };
+    }
+
+    static constexpr ErrorCode FromResultCode(ResultCode result) {
+        return {
+            .error_category{2000 + static_cast<u32>(result.module.Value())},
+            .error_number{result.description.Value()},
+        };
+    }
+
+    constexpr ResultCode ToResultCode() const {
+        return ResultCode{static_cast<ErrorModule>(error_category - 2000), error_number};
+    }
+};
+static_assert(sizeof(ErrorCode) == 0x8, "ErrorCode has incorrect size.");
+
 #pragma pack(push, 4)
 struct ShowError {
     u8 mode;
@@ -76,12 +100,7 @@ void CopyArgumentData(const std::vector<u8>& data, T& variable) {
 }
 
 ResultCode Decode64BitError(u64 error) {
-    const auto description = (error >> 32) & 0x1FFF;
-    auto module = error & 0x3FF;
-    if (module >= 2000)
-        module -= 2000;
-    module &= 0x1FF;
-    return {static_cast<ErrorModule>(module), static_cast<u32>(description)};
+    return ErrorCode::FromU64(error).ToResultCode();
 }
 
 } // Anonymous namespace