[release/6.0] Load R2R images on osx-arm64 according to Apple's guidelines (#67438)

* Fix Compiler::impImportNewObjArray on osx-arm64

* Reject R2R images containing calls to CORINFO_HELP_NEW_MDARR

* Load R2R images on osx-arm64 according to Apple's guidelines

Author: jgiannuzzi

src/coreclr/jit/importer.cpp

@@ -6960,7 +6960,9 @@ void Compiler::impImportNewObjArray(CORINFO_RESOLVED_TOKEN* pResolvedToken, CORI
     //
     CLANG_FORMAT_COMMENT_ANCHOR;
 
+#ifndef OSX_ARM64_ABI
     if (!opts.IsReadyToRun() || IsTargetAbi(CORINFO_CORERT_ABI))
+#endif // !OSX_ARM64_ABI
     {
 
         // Reuse the temp used to pass the array dimensions to avoid bloating
@@ -7017,6 +7019,7 @@ void Compiler::impImportNewObjArray(CORINFO_RESOLVED_TOKEN* pResolvedToken, CORI
 
         node = gtNewHelperCallNode(CORINFO_HELP_NEW_MDARR_NONVARARG, TYP_REF, args);
     }
+#ifndef OSX_ARM64_ABI
     else
     {
         //
@@ -7046,6 +7049,7 @@ void Compiler::impImportNewObjArray(CORINFO_RESOLVED_TOKEN* pResolvedToken, CORI
         }
 #endif
     }
+#endif // !OSX_ARM64_ABI
 
     for (GenTreeCall::Use& use : node->AsCall()->Args())
     {

src/coreclr/pal/src/map/map.cpp

@@ -2045,14 +2045,48 @@ MAPmmapAndRecord(
         // Mojave hardened runtime doesn't allow executable mappings of a file. So we have to create an
         // anonymous mapping and read the file contents into it instead.
 
+#if defined(HOST_ARM64)
+        // Set the requested mapping with forced PROT_WRITE, mmap the file, and copy its contents there.
+        // Once PROT_WRITE and PROT_EXEC are set together, Apple Silicon will require the use of
+        // PAL_JitWriteProtect to switch between executable and writable.
+        LPVOID pvMappedFile = mmap(NULL, len + adjust, PROT_READ, MAP_PRIVATE, fd, offset - adjust);
+        if (MAP_FAILED == pvMappedFile)
+        {
+            ERROR_(LOADER)("mmap failed with code %d: %s.\n", errno, strerror(errno));
+            palError = FILEGetLastErrorFromErrno();
+        }
+        else
+        {
+            if (-1 == mprotect(pvBaseAddress, len + adjust, prot | PROT_WRITE))
+            {
+                ERROR_(LOADER)("mprotect failed with code %d: %s.\n", errno, strerror(errno));
+                palError = FILEGetLastErrorFromErrno();
+            }
+            else
+            {
+                PAL_JitWriteProtect(true);
+                memcpy(pvBaseAddress, pvMappedFile, len + adjust);
+                PAL_JitWriteProtect(false);
+            }
+            if (-1 == munmap(pvMappedFile, len + adjust))
+            {
+                ERROR_(LOADER)("Unable to unmap the file. Expect trouble.\n");
+                if (NO_ERROR == palError)
+                    palError = FILEGetLastErrorFromErrno();
+            }
+        }
+#else
         // Set the requested mapping with forced PROT_WRITE to ensure data from the file can be read there,
-        // read the data in and finally remove the forced PROT_WRITE
+        // read the data in and finally remove the forced PROT_WRITE. On Intel we can still switch the
+        // protection later with mprotect.
         if ((mprotect(pvBaseAddress, len + adjust, prot | PROT_WRITE) == -1) ||
             (pread(fd, pvBaseAddress, len + adjust, offset - adjust) == -1) ||
             (((prot & PROT_WRITE) == 0) && mprotect(pvBaseAddress, len + adjust, prot) == -1))
         {
             palError = FILEGetLastErrorFromErrno();
         }
+#endif
+
     }
     else
 #endif

src/coreclr/vm/jitinterface.cpp

@@ -14200,6 +14200,13 @@ BOOL LoadDynamicInfoEntry(Module *currentModule,
             CorInfoHelpFunc corInfoHelpFunc = MapReadyToRunHelper((ReadyToRunHelper)helperNum);
             if (corInfoHelpFunc != CORINFO_HELP_UNDEF)
             {
+#ifdef OSX_ARM64_ABI
+                if (corInfoHelpFunc == CORINFO_HELP_NEW_MDARR)
+                {
+                    STRESS_LOG(LF_ZAP, LL_WARNING, "CORINFO_HELP_NEW_MDARR is not supported on osx-arm64\n");
+                    return FALSE;
+                }
+#endif // OSX_ARM64_ABI
                 result = (size_t)CEEJitInfo::getHelperFtnStatic(corInfoHelpFunc);
             }
             else

src/coreclr/vm/peimagelayout.cpp

@@ -213,13 +213,18 @@ void PEImageLayout::ApplyBaseRelocations()
             // Restore the protection
             if (dwOldProtection != 0)
             {
+#if defined(__APPLE__) && defined(HOST_ARM64)
                 BOOL bExecRegion = (dwOldProtection & (PAGE_EXECUTE | PAGE_EXECUTE_READ |
                     PAGE_EXECUTE_READWRITE | PAGE_EXECUTE_WRITECOPY)) != 0;
 
+                // Disable writing on Apple Silicon
+                if (bExecRegion)
+                    PAL_JitWriteProtect(false);
+#else
                 if (!ClrVirtualProtect(pWriteableRegion, cbWriteableRegion,
                                        dwOldProtection, &dwOldProtection))
                     ThrowLastError();
-
+#endif // __APPLE__ && HOST_ARM64
                 dwOldProtection = 0;
             }
 
@@ -238,14 +243,21 @@ void PEImageLayout::ApplyBaseRelocations()
 #if defined(TARGET_UNIX) && !defined(CROSSGEN_COMPILE)
                 if (((pSection->Characteristics & VAL32(IMAGE_SCN_MEM_EXECUTE)) != 0))
                 {
+#if defined(__APPLE__) && defined(HOST_ARM64)
+                    // Enable writing on Apple Silicon
+                    PAL_JitWriteProtect(true);
+#else
                     // On SELinux, we cannot change protection that doesn't have execute access rights
                     // to one that has it, so we need to set the protection to RWX instead of RW
                     dwNewProtection = PAGE_EXECUTE_READWRITE;
+#endif // __APPLE__ && HOST_ARM64
                 }
 #endif // TARGET_UNIX && !CROSSGEN_COMPILE
+#if !(defined(__APPLE__) && defined(HOST_ARM64))
                 if (!ClrVirtualProtect(pWriteableRegion, cbWriteableRegion,
                                        dwNewProtection, &dwOldProtection))
                     ThrowLastError();
+#endif // !(__APPLE__ && HOST_ARM64)
 #ifdef TARGET_UNIX
                 dwOldProtection = SectionCharacteristicsToPageProtection(pSection->Characteristics);
 #endif // TARGET_UNIX
@@ -307,13 +319,19 @@ void PEImageLayout::ApplyBaseRelocations()
 #ifndef CROSSGEN_COMPILE
     if (dwOldProtection != 0)
     {
+#if defined(__APPLE__) && defined(HOST_ARM64)
         BOOL bExecRegion = (dwOldProtection & (PAGE_EXECUTE | PAGE_EXECUTE_READ |
             PAGE_EXECUTE_READWRITE | PAGE_EXECUTE_WRITECOPY)) != 0;
 
+        // Disable writing on Apple Silicon
+        if (bExecRegion)
+            PAL_JitWriteProtect(false);
+#else
         // Restore the protection
         if (!ClrVirtualProtect(pWriteableRegion, cbWriteableRegion,
                                dwOldProtection, &dwOldProtection))
             ThrowLastError();
+#endif // __APPLE__ && HOST_ARM64
     }
 #ifdef TARGET_UNIX
     PAL_LOADMarkSectionAsNotNeeded((void*)dir);