Bug 1496173 - More aarch64 interceptor fixups. r=mhowell

browser/app/winlauncher/LauncherProcessWin.cpp

@@ -40,11 +40,12 @@ PostCreationSetup(HANDLE aChildProcess, HANDLE aChildMainThread,
 {
   // The launcher process's DLL blocking code is incompatible with ASAN because
   // it is able to execute before ASAN itself has even initialized.
-#if defined(MOZ_ASAN)
+  // Also, the AArch64 build doesn't yet have a working interceptor.
+#if defined(MOZ_ASAN) || defined(_M_ARM64)
   return true;
 #else
   return mozilla::InitializeDllBlocklistOOP(aChildProcess);
-#endif // defiend(MOZ_ASAN)
+#endif // defined(MOZ_ASAN) || defined(_M_ARM64)
 }
 
 #if !defined(PROCESS_CREATION_MITIGATION_POLICY_IMAGE_LOAD_PREFER_SYSTEM32_ALWAYS_ON)

mozglue/misc/interceptor/PatcherDetour.h

@@ -54,13 +54,17 @@ public:
     size_t nBytes = 2 + sizeof(intptr_t);
 #elif defined(_M_ARM64)
     size_t nBytes = 4;
-    MOZ_RELEASE_ASSERT(false, "Shouldn't get here");
 #else
 #error "Unknown processor type"
 #endif
 
     const auto& tramps = this->mVMPolicy.Items();
     for (auto&& tramp : tramps) {
+
+#if defined(_M_ARM64)
+      MOZ_RELEASE_ASSERT(false, "Shouldn't get here");
+#endif
+
       // First we read the pointer to the interceptor instance.
       Maybe<uintptr_t> instance = tramp.ReadEncodedPointer();
       if (!instance) {

mozglue/misc/nsWindowsDllInterceptor.h

@@ -432,12 +432,6 @@ private:
   {
     // Generally, code should not call this method directly. Use AddHook unless
     // there is a specific need to avoid nop space patches.
-#if defined(_M_ARM64)
-    // XXX: this is just to get things compiling; we'll have to add real
-    // support at some future point.
-    return false;
-#endif
-
     if (!mModule) {
       return false;
     }
@@ -454,6 +448,12 @@ private:
   {
     MOZ_ASSERT(mModule && aProc);
 
+#if defined(_M_ARM64)
+    // XXX: this is just to get things compiling; we'll have to add real
+    // support at some future point.
+    return false;
+#endif
+
     if (!mDetourPatcher.Initialized()) {
       mDetourPatcher.Init(mNHooks);
     }