Pass a second type argument vector to all type instantiation calls in the VM.

runtime/vm/stub_code_x64.cc

Index: runtime/vm/stub_code_x64.cc
diff --git a/runtime/vm/stub_code_x64.cc b/runtime/vm/stub_code_x64.cc
index 5187e1eb423e8080b6284a1e9f5a5a89b767b84a..a68eaab83827e34e7a61a0c62daa3014afdd14e0 100644
--- a/runtime/vm/stub_code_x64.cc
+++ b/runtime/vm/stub_code_x64.cc
@@ -1729,15 +1729,17 @@ void StubCode::GenerateDebugStepCheckStub(Assembler* assembler) {
 
 // Used to check class and type arguments. Arguments passed on stack:
 // TOS + 0: return address.
-// TOS + 1: instantiator type arguments (can be NULL).
-// TOS + 2: instance.
-// TOS + 3: SubtypeTestCache.
+// TOS + 1: function type arguments (only if n == 4, can be raw_null).
+// TOS + 2: instantiator type arguments (only if n == 4, can be raw_null).
+// TOS + 3: instance.
+// TOS + 4: SubtypeTestCache.
 // Result in RCX: null -> not found, otherwise result (true or false).
 static void GenerateSubtypeNTestCacheStub(Assembler* assembler, int n) {
-  ASSERT((1 <= n) && (n <= 3));
-  const intptr_t kInstantiatorTypeArgumentsInBytes = 1 * kWordSize;
-  const intptr_t kInstanceOffsetInBytes = 2 * kWordSize;
-  const intptr_t kCacheOffsetInBytes = 3 * kWordSize;
+  ASSERT((n == 1) || (n == 2) || (n == 4));
+  const intptr_t kFunctionTypeArgumentsInBytes = 1 * kWordSize;
+  const intptr_t kInstantiatorTypeArgumentsInBytes = 2 * kWordSize;
+  const intptr_t kInstanceOffsetInBytes = 3 * kWordSize;
+  const intptr_t kCacheOffsetInBytes = 4 * kWordSize;
   __ movq(RAX, Address(RSP, kInstanceOffsetInBytes));
   __ LoadObject(R9, Object::null_object());
   if (n > 1) {
@@ -1791,6 +1793,10 @@ static void GenerateSubtypeNTestCacheStub(Assembler* assembler, int n) {
               Address(RDX, kWordSize *
                                SubtypeTestCache::kInstantiatorTypeArguments));
       __ cmpq(RDI, Address(RSP, kInstantiatorTypeArgumentsInBytes));
+      __ j(NOT_EQUAL, &next_iteration, Assembler::kNearJump);
+      __ movq(RDI, Address(RDX, kWordSize *
+                                    SubtypeTestCache::kFunctionTypeArguments));
+      __ cmpq(RDI, Address(RSP, kFunctionTypeArgumentsInBytes));
       __ j(EQUAL, &found, Assembler::kNearJump);
     }
   }
@@ -1811,9 +1817,10 @@ static void GenerateSubtypeNTestCacheStub(Assembler* assembler, int n) {
 
 // Used to check class and type arguments. Arguments passed on stack:
 // TOS + 0: return address.
-// TOS + 1: instantiator type arguments or NULL.
-// TOS + 2: instance.
-// TOS + 3: cache array.
+// TOS + 1: raw_null.
+// TOS + 2: raw_null.
+// TOS + 3: instance.
+// TOS + 4: SubtypeTestCache.
 // Result in RCX: null -> not found, otherwise result (true or false).
 void StubCode::GenerateSubtype1TestCacheStub(Assembler* assembler) {
   GenerateSubtypeNTestCacheStub(assembler, 1);
@@ -1822,9 +1829,10 @@ void StubCode::GenerateSubtype1TestCacheStub(Assembler* assembler) {
 
 // Used to check class and type arguments. Arguments passed on stack:
 // TOS + 0: return address.
-// TOS + 1: instantiator type arguments or NULL.
-// TOS + 2: instance.
-// TOS + 3: cache array.
+// TOS + 1: raw_null.
+// TOS + 2: raw_null.
+// TOS + 3: instance.
+// TOS + 4: SubtypeTestCache.
 // Result in RCX: null -> not found, otherwise result (true or false).
 void StubCode::GenerateSubtype2TestCacheStub(Assembler* assembler) {
   GenerateSubtypeNTestCacheStub(assembler, 2);
@@ -1833,12 +1841,13 @@ void StubCode::GenerateSubtype2TestCacheStub(Assembler* assembler) {
 
 // Used to check class and type arguments. Arguments passed on stack:
 // TOS + 0: return address.
-// TOS + 1: instantiator type arguments.
-// TOS + 2: instance.
-// TOS + 3: cache array.
+// TOS + 1: function type arguments (can be raw_null).
+// TOS + 2: instantiator type arguments (can be raw_null).
+// TOS + 3: instance.
+// TOS + 4: SubtypeTestCache.
 // Result in RCX: null -> not found, otherwise result (true or false).
-void StubCode::GenerateSubtype3TestCacheStub(Assembler* assembler) {
-  GenerateSubtypeNTestCacheStub(assembler, 3);
+void StubCode::GenerateSubtype4TestCacheStub(Assembler* assembler) {
+  GenerateSubtypeNTestCacheStub(assembler, 4);
 }