Unify macOS ARM64 write protection holders with W^X ones (#54067)

* Unify macOS ARM64 write protection holders with W^X ones

This change removes the original holders that were added for changing
memory protection for executable code and moves the actual switching to
the recently added W^X holders.

The unixexports files don't support target specific symbols. So I needed
to export a dummy version of the PAL_JitWriteProtect for macOS x64.

2 files changed, 10 insertions, 9 deletions

diff --git a/src/coreclr/inc/executableallocator.h b/src/coreclr/inc/executableallocator.h
index 6a2cecda085..c71f613dbe5 100644
--- a/src/coreclr/inc/executableallocator.h
+++ b/src/coreclr/inc/executableallocator.h
@@ -30,7 +30,13 @@ class ExecutableWriterHolder
 
     void Unmap()
     {
-        // TODO: this will be added with the double mapped allocator addition 
+        if (m_addressRX != NULL)
+        {
+            // TODO: mapping / unmapping for targets using double memory mapping  will be added with the double mapped allocator addition 
+#if defined(HOST_OSX) && defined(HOST_ARM64)
+            PAL_JitWriteProtect(false);
+#endif
+        }
     }
 
 public:
@@ -57,6 +63,9 @@ public:
     {
         m_addressRX = addressRX;
         m_addressRW = addressRX;
+#if defined(HOST_OSX) && defined(HOST_ARM64)
+        PAL_JitWriteProtect(true);
+#endif
     }
 
     ~ExecutableWriterHolder()
diff --git a/src/coreclr/inc/loaderheap.h b/src/coreclr/inc/loaderheap.h
index 2dc156572b4..ac0669a5586 100644
--- a/src/coreclr/inc/loaderheap.h
+++ b/src/coreclr/inc/loaderheap.h
@@ -554,10 +554,6 @@ private:
     {
         WRAPPER_NO_CONTRACT;
 
-#if defined(HOST_OSX) && defined(HOST_ARM64)
-        auto jitWriteEnableHolder = PAL_JITWriteEnable(true);
-#endif // defined(HOST_OSX) && defined(HOST_ARM64)
-
         void *pResult;
         TaggedMemAllocPtr tmap;
 
@@ -634,10 +630,6 @@ public:
     {
         WRAPPER_NO_CONTRACT;
 
-#if defined(HOST_OSX) && defined(HOST_ARM64)
-        auto jitWriteEnableHolder = PAL_JITWriteEnable(true);
-#endif // defined(HOST_OSX) && defined(HOST_ARM64)
-
         CRITSEC_Holder csh(m_CriticalSection);