[K/N] Add signposts to safepoints ^KT-62689

Disabled by default.

Merge-request: KT-MR-12679
Merged-by: Alexander Shabalin <Alexander.Shabalin@jetbrains.com>

kotlin-native/runtime/src/main/cpp/CompilerConstants.cpp

@@ -32,6 +32,7 @@ RUNTIME_WEAK int32_t Kotlin_appStateTracking = 0;
 RUNTIME_WEAK int32_t Kotlin_mimallocUseDefaultOptions = 1;
 RUNTIME_WEAK int32_t Kotlin_mimallocUseCompaction = 0;
 RUNTIME_WEAK int32_t Kotlin_objcDisposeOnMain = 0;
+RUNTIME_WEAK int32_t Kotlin_enableSafepointSignposts = 0;
 
 ALWAYS_INLINE compiler::DestroyRuntimeMode compiler::destroyRuntimeMode() noexcept {
     return static_cast<compiler::DestroyRuntimeMode>(Kotlin_destroyRuntimeMode);
@@ -83,3 +84,7 @@ ALWAYS_INLINE bool compiler::mimallocUseCompaction() noexcept {
 ALWAYS_INLINE bool compiler::objcDisposeOnMain() noexcept {
     return Kotlin_objcDisposeOnMain != 0;
 }
+
+ALWAYS_INLINE bool compiler::enableSafepointSignposts() noexcept {
+    return Kotlin_enableSafepointSignposts != 0;
+}

kotlin-native/runtime/src/main/cpp/CompilerConstants.hpp

@@ -113,6 +113,7 @@ int getSourceInfo(void* addr, SourceInfo *result, int result_size) noexcept;
 bool mimallocUseDefaultOptions() noexcept;
 bool mimallocUseCompaction() noexcept;
 bool objcDisposeOnMain() noexcept;
+bool enableSafepointSignposts() noexcept;
 
 #ifdef KONAN_ANDROID
 bool printToAndroidLogcat() noexcept;

kotlin-native/runtime/src/mm/cpp/SafePoint.cpp

@@ -13,6 +13,16 @@
 #include "ThreadData.hpp"
 #include "ThreadState.hpp"
 
+// TODO: Remove after the bootstrap that brings changes in ClangArgs.kt
+#ifndef KONAN_SUPPORTS_SIGNPOSTS
+#define KONAN_SUPPORTS_SIGNPOSTS KONAN_MACOSX || KONAN_IOS || KONAN_WATCHOS || KONAN_TVOS
+#endif
+
+#if KONAN_SUPPORTS_SIGNPOSTS
+#include <os/log.h>
+#include <os/signpost.h>
+#endif
+
 using namespace kotlin;
 
 namespace {
@@ -21,11 +31,45 @@ namespace {
 int64_t activeCount = 0;
 std::atomic<void (*)(mm::ThreadData&)> safePointAction = nullptr;
 
+#if KONAN_SUPPORTS_SIGNPOSTS
+
+#define SAFEPOINT_SIGNPOST_NAME "Safepoint" // signpost API requires strings be literals
+
+class SafePointSignpostInterval : private Pinned {
+public:
+    explicit SafePointSignpostInterval(mm::ThreadData& threadData) noexcept : id_(os_signpost_id_make_with_pointer(logObject, &threadData)) {
+        os_signpost_interval_begin(logObject, id_, SAFEPOINT_SIGNPOST_NAME, "thread id: %d", threadData.threadId());
+    }
+
+    ~SafePointSignpostInterval() {
+        os_signpost_interval_end(logObject, id_, SAFEPOINT_SIGNPOST_NAME);
+    }
+
+private:
+    static os_log_t logObject;
+    uint64_t id_;
+};
+
+#undef SAFEPOINT_SIGNPOST_NAME
+
+// static
+os_log_t SafePointSignpostInterval::logObject = os_log_create("org.kotlinlang.native.runtime", "safepoint");
+#else
+class SafePointSignpostInterval : private Pinned {
+public:
+    explicit SafePointSignpostInterval(mm::ThreadData& threadData) noexcept {}
+};
+#endif
+
 void safePointActionImpl(mm::ThreadData& threadData) noexcept {
     static thread_local bool recursion = false;
     RuntimeAssert(!recursion, "Recursive safepoint");
     AutoReset guard(&recursion, true);
 
+    std::optional<SafePointSignpostInterval> signpost;
+    if (compiler::enableSafepointSignposts()) {
+        signpost.emplace(threadData);
+    }
     threadData.gcScheduler().safePoint();
     threadData.gc().safePoint();
     threadData.suspensionData().suspendIfRequested();