Bug 1906827 part 2 - add tests and make all cppunittests pass on ARM64 r=yjuglaret

Differential Revision: https://phabricator.services.mozilla.com/D269396

Author: gregstoll

toolkit/xre/dllservices/tests/TestArm64Disassembler.cpp

@@ -26,11 +26,13 @@
 using namespace mozilla;
 using namespace mozilla::interceptor::arm64;
 
+constexpr uintptr_t kExamplePCValue = 0x7ff959a7ea80;
+
 bool TestCheckForPCRelAdrp() {
   // A real-world example from bug 1964688 comment 5:
   // 00007ff9`59a7ea80 d0dfff11 adrp xip1,00007ff9`19a60000
   Result<LoadOrBranch, PCRelCheckError> result =
-      CheckForPCRel(0x7ff959a7ea80, 0xd0dfff11);
+      CheckForPCRel(kExamplePCValue, 0xd0dfff11);
   if (result.isErr()) {
     auto error = result.unwrapErr();
     TEST_FAILED(
@@ -65,7 +67,7 @@ bool TestCheckForPCRelAdr() {
   // Fictional example with adr:
   // 00007ff959a7ea80 50dfff11 adr x17, #0x7ff959a3ea62
   Result<LoadOrBranch, PCRelCheckError> result =
-      CheckForPCRel(0x7ff959a7ea80, 0x50dfff11);
+      CheckForPCRel(kExamplePCValue, 0x50dfff11);
 
   // For the moment we expect to recognize adr instructions but we don't have
   // a decoder
@@ -90,8 +92,56 @@ bool TestCheckForPCRelAdr() {
   return true;
 }
 
+bool TestCheckForPCRelBlr() {
+  // blr x16
+  Result<LoadOrBranch, PCRelCheckError> result =
+      CheckForPCRel(kExamplePCValue, 0xd63f0200);
+
+  if (!result.isErr()) {
+    TEST_FAILED(
+        "Unexpectedly recognized blr as a PC-relative instruction with a "
+        "decoder. If you have implemented a decoder for this instruction, "
+        "please update TestArm64Disassembler.cpp.\n");
+  }
+
+  auto error = result.unwrapErr();
+  if (error != PCRelCheckError::NoDecoderAvailable) {
+    TEST_FAILED(
+        "Failed to recognize blr as a PC-relative instruction, got "
+        "PCRelCheckError %d.\n",
+        error);
+  }
+
+  TEST_PASS(
+      "Properly recognized blr as a PC-relative instruction without a "
+      "decoder.\n");
+  return true;
+}
+
+bool TestCheckForPCRelBr() {
+  // br x16
+  Result<LoadOrBranch, PCRelCheckError> result =
+      CheckForPCRel(kExamplePCValue, 0xd61f0200);
+
+  if (result.isErr()) {
+    auto error = result.unwrapErr();
+    if (error != PCRelCheckError::InstructionNotPCRel) {
+      TEST_FAILED(
+          "Failed to recognize br as a non-PC-relative instruction, got "
+          "PCRelCheckError %d.\n",
+          error);
+    }
+  } else {
+    TEST_FAILED("Incorrectly recognized br as a PC-relative instruction.\n");
+  }
+
+  TEST_PASS("Properly recognized br as a non-PC-relative instruction.\n");
+  return true;
+}
+
 int wmain(int argc, wchar_t* argv[]) {
-  if (!TestCheckForPCRelAdrp() || !TestCheckForPCRelAdr()) {
+  if (!TestCheckForPCRelAdrp() || !TestCheckForPCRelAdr() ||
+      !TestCheckForPCRelBlr() || !TestCheckForPCRelBr()) {
     return -1;
   }
   return 0;

toolkit/xre/dllservices/tests/TestDllInterceptor.cpp

@@ -848,10 +848,10 @@ MOZ_GLOBINIT struct TestCase {
     TestCase("LockPrefix", NoStubAddressCheck),
     TestCase("LooksLikeLockPrefix", NoStubAddressCheck),
 #  endif
-#  if !defined(DEBUG)
+#  if !defined(_M_ARM64) && !defined(DEBUG)
     // Skip on Debug build because it hits MOZ_ASSERT_UNREACHABLE.
     TestCase("UnsupportedOp", ExpectedFail),
-#  endif  // !defined(DEBUG)
+#  endif  // !defined(_M_ARM64) && !defined(DEBUG)
 #endif    // defined(__clang__)
 };
 
@@ -892,7 +892,9 @@ bool TestAssemblyFunctions() {
           DetourResultCode::DETOUR_PATCHER_CREATE_TRAMPOLINE_ERROR) {
         printf(
             "TEST-FAILED | WindowsDllInterceptor | "
-            "A wrong detour errorcode was set on detour error.\n");
+            "A wrong detour errorcode was set on detour error for %s. (got "
+            "%d)\n",
+            testCase.mFunctionName, maybeError.ref().mErrorCode);
         return false;
       }
 #endif  // defined(NIGHTLY_BUILD)

toolkit/xre/dllservices/tests/moz.build

@@ -8,18 +8,19 @@ GeckoCppUnitTests(
     [
         "TestDllBlocklistAssumptions",
         "TestDllInterceptor",
-        "TestIATPatcher",
         "TestMMPolicy",
         "TestOleAut32Initialization",
     ],
     linkage=None,
 )
 
 if CONFIG["TARGET_CPU"] in ("x86", "x86_64"):
-    # Cross-process interceptors not yet supported on aarch64
     GeckoCppUnitTests(
         [
+            # Cross-process interceptors not yet supported on aarch64
             "TestDllInterceptorCrossProcess",
+            # Requires administrator permission on aarch64
+            "TestIATPatcher",
         ],
         linkage=None,
     )