[ios/tvos] ARM64 simulator JIT Hack and CMAKE_SYSTEM_VARIANT iOSSimulator

eng/native/build-commons.sh

@@ -94,6 +94,10 @@ build_native()
         cmakeArgs="-DCMAKE_SYSTEM_VARIANT=MacCatalyst $cmakeArgs"
     fi
 
+    if [[ "$targetOS" == "iOSSimulator" || "$targetOS" == "tvOSSimulator" ]]; then
+        cmakeArgs="-DCMAKE_SYSTEM_VARIANT=$targetOS $cmakeArgs"
+    fi
+
     if [[ "$__UseNinja" == 1 ]]; then
         generator="ninja"
         buildTool="$(command -v ninja || command -v ninja-build)"

src/mono/CMakeLists.txt

@@ -213,6 +213,9 @@ elseif(CMAKE_SYSTEM_NAME STREQUAL "iOS" OR CMAKE_SYSTEM_NAME STREQUAL "tvOS")
   add_definitions("-DSMALL_CONFIG")
   add_definitions("-D_XOPEN_SOURCE")
   add_definitions("-DHAVE_LARGE_FILE_SUPPORT=1")
+  if (CMAKE_SYSTEM_VARIANT STREQUAL "iOSSimulator" OR CMAKE_SYSTEM_VARIANT STREQUAL "tvOSSimulator")
+    set (HOST_DARWIN_SIMULATOR 1)
+  endif()
 elseif(CMAKE_SYSTEM_NAME STREQUAL "Linux")
   set(HOST_LINUX 1)
   add_definitions(-D_GNU_SOURCE -D_REENTRANT)

src/mono/cmake/config.h.in

@@ -116,6 +116,9 @@
 /* Host Platform is Mac Catalyst */
 #cmakedefine HOST_MACCAT 1
 
+/* Host Platform is iOS or tvOS simulator */
+#cmakedefine HOST_DARWIN_SIMULATOR 1
+
 /* Use classic Windows API support */
 #cmakedefine HAVE_CLASSIC_WINAPI_SUPPORT 1
 

src/mono/mono/utils/CMakeLists.txt

@@ -33,6 +33,8 @@ set(utils_common_sources
     mono-logger.c
     mono-logger-internals.h
     mono-codeman.c
+    write-protect.c
+    write-protect.h
     mono-counters.c
     mono-compiler.h
     mono-dl.c

src/mono/mono/utils/mono-codeman.c

@@ -28,6 +28,7 @@ static void* mono_code_manager_heap;
 
 #include <mono/utils/mono-os-mutex.h>
 #include <mono/utils/mono-tls.h>
+#include <mono/utils/write-protect.h>
 
 static uintptr_t code_memory_used = 0;
 static size_t dynamic_code_alloc_count;
@@ -652,6 +653,16 @@ mono_code_manager_size (MonoCodeManager *cman, int *used_size)
 	return size;
 }
 
+#ifdef HAVE_PTHREAD_JIT_WRITE_PROTECT_NP
+#define JIT_WRITE_PROTECT(enable) pthread_jit_write_protect_np ((enable))
+#define JIT_WRITE_PROTECT_AVAIL() (__builtin_available (macOS 11, *))
+#define USE_WRITE_PROTECT 1
+#elif (defined(HOST_IOS) || defined(HOST_TVOS)) && defined(HOST_DARWIN_SIMULATOR) && defined(HOST_ARM64)
+#define USE_WRITE_PROTECT 1
+#define JIT_WRITE_PROTECT(enable) mono_jit_write_protect ((enable))
+#define JIT_WRITE_PROTECT_AVAIL() 1
+#endif
+
 /*
  * mono_codeman_enable_write ():
  *
@@ -661,16 +672,13 @@ mono_code_manager_size (MonoCodeManager *cman, int *used_size)
 void
 mono_codeman_enable_write (void)
 {
-#ifdef HAVE_PTHREAD_JIT_WRITE_PROTECT_NP
-	if (__builtin_available (macOS 11, *)) {
+#ifdef USE_WRITE_PROTECT
+	if (JIT_WRITE_PROTECT_AVAIL()) {
 		int level = GPOINTER_TO_INT (mono_native_tls_get_value (write_level_tls_id));
 		level ++;
 		mono_native_tls_set_value (write_level_tls_id, GINT_TO_POINTER (level));
-		pthread_jit_write_protect_np (0);
+		JIT_WRITE_PROTECT (0);
 	}
-#elif defined(HOST_MACCAT) && defined(__aarch64__)
-	/* JITing in Catalyst apps is not allowed on Apple Silicon. */
-	g_assert_not_reached ();
 #endif
 }
 
@@ -683,17 +691,14 @@ mono_codeman_enable_write (void)
 void
 mono_codeman_disable_write (void)
 {
-#ifdef HAVE_PTHREAD_JIT_WRITE_PROTECT_NP
-	if (__builtin_available (macOS 11, *)) {
+#ifdef USE_WRITE_PROTECT
+	if (JIT_WRITE_PROTECT_AVAIL()) {
 		int level = GPOINTER_TO_INT (mono_native_tls_get_value (write_level_tls_id));
 		g_assert (level);
 		level --;
 		mono_native_tls_set_value (write_level_tls_id, GINT_TO_POINTER (level));
 		if (level == 0)
-			pthread_jit_write_protect_np (1);
+			JIT_WRITE_PROTECT (1);
 	}
-#elif defined(HOST_MACCAT) && defined(__aarch64__)
-	/* JITing in Catalyst apps is not allowed on Apple Silicon. */
-	g_assert_not_reached ();
 #endif
 }

src/mono/mono/utils/write-protect.c

@@ -0,0 +1,27 @@
+/**
+ * \file
+ */
+
+#include "config.h"
+
+#include "mono-compiler.h"
+#include "write-protect.h"
+
+#if (defined(HOST_IOS) || defined(HOST_TVOS)) && defined (HOST_DARWIN_SIMULATOR) && defined (HOST_ARM64)
+
+/* our own declaration of pthread_jit_write_protect_np so that we don't see the __API_UNAVAILABLE__ header */
+void
+pthread_jit_write_protect_np (int enabled);
+
+
+void
+mono_jit_write_protect (int enabled)
+{
+        pthread_jit_write_protect_np (enabled);
+}
+
+#else /* (defined(HOST_IOS) || defined(HOST_TVOS)) && defined (HOST_DARWIN_SIMULATOR) && defined (HOST_ARM64) */
+
+MONO_EMPTY_SOURCE_FILE (write_protect);
+
+#endif

src/mono/mono/utils/write-protect.h

@@ -0,0 +1,16 @@
+/**
+ * \file
+ */
+
+#ifndef __MONO_WRITE_PROTECT_H__
+#define __MONO_WRITE_PROTECT_H__
+
+#include <mono/utils/mono-publib.h>
+
+#if (defined(HOST_IOS) || defined(HOST_TVOS)) && defined (HOST_DARWIN_SIMULATOR) && defined (HOST_ARM64)
+mono_jit_write_protect (int enabled);
+
+#endif /* (defined(HOST_IOS) || defined(HOST_TVOS)) && defined (HOST_DARWIN_SIMULATOR) && defined (HOST_ARM64) */
+
+#endif /* __MONO_WRITE_PROTECT_H__ */
+