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

runtime/vm/flow_graph_compiler_mips.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"  // Needed here to get TARGET_ARCH_MIPS.
 #if defined(TARGET_ARCH_MIPS)
 
 #include "vm/flow_graph_compiler.h"
 
 #include "vm/ast_printer.h"
@@ skipping 183 matching lines @@
   Label fall_through;
   __ BranchEqual(bool_register, Object::null_object(), &fall_through);
   __ BranchEqual(bool_register, Bool::True(), is_true);
   __ b(is_false);
   __ Bind(&fall_through);
 }
 
 
 // A0: instance (must be preserved).
 // A1: instantiator type arguments (if used).
+// A2: function type arguments (if used).

[siva, 2017/04/10 22:04:55]

doesn't seem to document that A3 is clobbered, I see such comments in other
functions below.

[regis, 2017/04/11 04:23:08]

Added.

I do not think that these comments are all accurate or complete. I corrected a
few in this cl, but I would not trust them.

 RawSubtypeTestCache* FlowGraphCompiler::GenerateCallSubtypeTestStub(
     TypeTestStubKind test_kind,
     Register instance_reg,
-    Register type_arguments_reg,
+    Register instantiator_type_arguments_reg,
+    Register function_type_arguments_reg,
     Register temp_reg,
     Label* is_instance_lbl,
     Label* is_not_instance_lbl) {
   __ Comment("CallSubtypeTestStub");
   ASSERT(instance_reg == A0);
   ASSERT(temp_reg == kNoRegister);  // Unused on MIPS.
   const SubtypeTestCache& type_test_cache =
       SubtypeTestCache::ZoneHandle(zone(), SubtypeTestCache::New());
-  __ LoadUniqueObject(A2, type_test_cache);
+  __ LoadUniqueObject(A3, type_test_cache);
   if (test_kind == kTestTypeOneArg) {
-    ASSERT(type_arguments_reg == kNoRegister);
-    __ LoadObject(A1, Object::null_object());
+    ASSERT(instantiator_type_arguments_reg == kNoRegister);
+    ASSERT(function_type_arguments_reg == kNoRegister);
     __ BranchLink(*StubCode::Subtype1TestCache_entry());
   } else if (test_kind == kTestTypeTwoArgs) {
-    ASSERT(type_arguments_reg == kNoRegister);
-    __ LoadObject(A1, Object::null_object());
+    ASSERT(instantiator_type_arguments_reg == kNoRegister);
+    ASSERT(function_type_arguments_reg == kNoRegister);
     __ BranchLink(*StubCode::Subtype2TestCache_entry());
-  } else if (test_kind == kTestTypeThreeArgs) {
-    ASSERT(type_arguments_reg == A1);
-    __ BranchLink(*StubCode::Subtype3TestCache_entry());
+  } else if (test_kind == kTestTypeFourArgs) {
+    ASSERT(instantiator_type_arguments_reg == A1);
+    ASSERT(function_type_arguments_reg == A2);
+    __ BranchLink(*StubCode::Subtype4TestCache_entry());
   } else {
     UNREACHABLE();
   }
   // Result is in V0: null -> not found, otherwise Bool::True or Bool::False.
   GenerateBoolToJump(V0, is_instance_lbl, is_not_instance_lbl);
   return type_test_cache.raw();
 }
 
 
 // Jumps to labels 'is_instance' or 'is_not_instance' respectively, if
@@ skipping 56 matching lines @@
         const Type& object_type = Type::Handle(zone(), Type::ObjectType());
         if (object_type.IsSubtypeOf(tp_argument, NULL, NULL, Heap::kOld)) {
           // Instance class test only necessary.
           return GenerateSubtype1TestCacheLookup(
               token_pos, type_class, is_instance_lbl, is_not_instance_lbl);
         }
       }
     }
   }
   // Regular subtype test cache involving instance's type arguments.
-  const Register kTypeArgumentsReg = kNoRegister;
+  const Register kInstantiatorTypeArgumentsReg = kNoRegister;
+  const Register kFunctionTypeArgumentsReg = kNoRegister;
   const Register kTempReg = kNoRegister;
   // A0: instance (must be preserved).
   return GenerateCallSubtypeTestStub(kTestTypeTwoArgs, kInstanceReg,
-                                     kTypeArgumentsReg, kTempReg,
+                                     kInstantiatorTypeArgumentsReg,
+                                     kFunctionTypeArgumentsReg, kTempReg,
                                      is_instance_lbl, is_not_instance_lbl);
 }
 
 
 void FlowGraphCompiler::CheckClassIds(Register class_id_reg,
                                       const GrowableArray<intptr_t>& class_ids,
                                       Label* is_equal_lbl,
                                       Label* is_not_equal_lbl) {
   __ Comment("CheckClassIds");
   for (intptr_t i = 0; i < class_ids.length(); i++) {
@@ skipping 63 matching lines @@
   if (!type_class.is_abstract()) {
     __ BranchEqual(kClassIdReg, Immediate(type_class.id()), is_instance_lbl);
   }
   // Otherwise fallthrough.
   return true;
 }
 
 
 // Uses SubtypeTestCache to store instance class and result.
 // A0: instance to test.
-// Clobbers A1, A2, T0-T3.
+// Clobbers A1-A3, T0-T3.
 // Immediate class test already done.
 // TODO(srdjan): Implement a quicker subtype check, as type test
 // arrays can grow too high, but they may be useful when optimizing
 // code (type-feedback).
 RawSubtypeTestCache* FlowGraphCompiler::GenerateSubtype1TestCacheLookup(
     TokenPosition token_pos,
     const Class& type_class,
     Label* is_instance_lbl,
     Label* is_not_instance_lbl) {
   __ Comment("Subtype1TestCacheLookup");
   const Register kInstanceReg = A0;
   __ LoadClass(T0, kInstanceReg);
   // T0: instance class.
   // Check immediate superclass equality.
   __ lw(T0, FieldAddress(T0, Class::super_type_offset()));
   __ lw(T0, FieldAddress(T0, Type::type_class_id_offset()));
   __ BranchEqual(T0, Immediate(Smi::RawValue(type_class.id())),
                  is_instance_lbl);
 
-  const Register kTypeArgumentsReg = kNoRegister;
+  const Register kInstantiatorTypeArgumentsReg = kNoRegister;
+  const Register kFunctionTypeArgumentsReg = kNoRegister;
   const Register kTempReg = kNoRegister;
   return GenerateCallSubtypeTestStub(kTestTypeOneArg, kInstanceReg,
-                                     kTypeArgumentsReg, kTempReg,
+                                     kInstantiatorTypeArgumentsReg,
+                                     kFunctionTypeArgumentsReg, kTempReg,
                                      is_instance_lbl, is_not_instance_lbl);
 }
 
 
 // Generates inlined check if 'type' is a type parameter or type itself
 // A0: instance (preserved).
 RawSubtypeTestCache* FlowGraphCompiler::GenerateUninstantiatedTypeTest(
     TokenPosition token_pos,
     const AbstractType& type,
     Label* is_instance_lbl,
     Label* is_not_instance_lbl) {
   __ Comment("UninstantiatedTypeTest");
   ASSERT(!type.IsInstantiated());
   // Skip check if destination is a dynamic type.
   if (type.IsTypeParameter()) {
     const TypeParameter& type_param = TypeParameter::Cast(type);
-    // Load instantiator type arguments on stack.
-    __ lw(A1, Address(SP, 0));  // Get instantiator type arguments.
+    __ lw(A1, Address(SP, 1 * kWordSize));  // Get instantiator type args.
+    __ lw(A2, Address(SP, 0 * kWordSize));  // Get function type args.
     // A1: instantiator type arguments.
+    // A2: function type arguments.
+    const Register kTypeArgumentsReg =
+        type_param.IsClassTypeParameter() ? A1 : A2;
     // Check if type arguments are null, i.e. equivalent to vector of dynamic.
     __ LoadObject(T7, Object::null_object());
-    __ beq(A1, T7, is_instance_lbl);
-    __ lw(T2,
-          FieldAddress(A1, TypeArguments::type_at_offset(type_param.index())));
-    // R2: concrete type of type.
+    __ beq(kTypeArgumentsReg, T7, is_instance_lbl);
+    __ lw(T2, FieldAddress(kTypeArgumentsReg,
+                           TypeArguments::type_at_offset(type_param.index())));
+    // T2: concrete type of type.
     // Check if type argument is dynamic.
     __ BranchEqual(T2, Object::dynamic_type(), is_instance_lbl);
     __ BranchEqual(T2, Type::ZoneHandle(zone(), Type::ObjectType()),
                    is_instance_lbl);
+    // TODO(regis): Optimize void type as well once allowed as type argument.
 
     // For Smi check quickly against int and num interfaces.
     Label not_smi;
     __ andi(CMPRES1, A0, Immediate(kSmiTagMask));
     __ bne(CMPRES1, ZR, &not_smi);  // Value is Smi?
     __ BranchEqual(T2, Type::ZoneHandle(zone(), Type::IntType()),
                    is_instance_lbl);
     __ BranchEqual(T2, Type::ZoneHandle(zone(), Type::Number()),
                    is_instance_lbl);
     // Smi must be handled in runtime.
     Label fall_through;
     __ b(&fall_through);
 
     __ Bind(&not_smi);
-    // T1: instantiator type arguments.
     // A0: instance.
+    // A1: instantiator type arguments.
+    // A2: function type arguments.
     const Register kInstanceReg = A0;
-    const Register kTypeArgumentsReg = A1;
+    const Register kInstantiatorTypeArgumentsReg = A1;
+    const Register kFunctionTypeArgumentsReg = A2;
     const Register kTempReg = kNoRegister;
     const SubtypeTestCache& type_test_cache = SubtypeTestCache::ZoneHandle(
         zone(), GenerateCallSubtypeTestStub(
-                    kTestTypeThreeArgs, kInstanceReg, kTypeArgumentsReg,
+                    kTestTypeFourArgs, kInstanceReg,
+                    kInstantiatorTypeArgumentsReg, kFunctionTypeArgumentsReg,
                     kTempReg, is_instance_lbl, is_not_instance_lbl));
     __ Bind(&fall_through);
     return type_test_cache.raw();
   }
   if (type.IsType()) {
     const Register kInstanceReg = A0;
-    const Register kTypeArgumentsReg = A1;
+    const Register kInstantiatorTypeArgumentsReg = A1;
+    const Register kFunctionTypeArgumentsReg = A2;
     __ andi(CMPRES1, kInstanceReg, Immediate(kSmiTagMask));
     __ beq(CMPRES1, ZR, is_not_instance_lbl);  // Is instance Smi?
-    __ lw(kTypeArgumentsReg, Address(SP, 0));  // Instantiator type args.
+    __ lw(kInstantiatorTypeArgumentsReg, Address(SP, 1 * kWordSize));
+    __ lw(kFunctionTypeArgumentsReg, Address(SP, 0 * kWordSize));
     // Uninstantiated type class is known at compile time, but the type
     // arguments are determined at runtime by the instantiator.
     const Register kTempReg = kNoRegister;
-    return GenerateCallSubtypeTestStub(kTestTypeThreeArgs, kInstanceReg,
-                                       kTypeArgumentsReg, kTempReg,
+    return GenerateCallSubtypeTestStub(kTestTypeFourArgs, kInstanceReg,
+                                       kInstantiatorTypeArgumentsReg,
+                                       kFunctionTypeArgumentsReg, kTempReg,
                                        is_instance_lbl, is_not_instance_lbl);
   }
   return SubtypeTestCache::null();
 }
 
 
 // Inputs:
 // - A0: instance being type checked (preserved).
 // - A1: optional instantiator type arguments (preserved).
+// - A2: optional function type arguments (preserved).
 // Returns:
-// - preserved instance in A0 and optional instantiator type arguments in A1.
+// - preserved instance in A0, optional instantiator type arguments in A1, and
+//   optional function type arguments in A2.
 // Clobbers: T0, T1, T2
 // Note that this inlined code must be followed by the runtime_call code, as it
 // may fall through to it. Otherwise, this inline code will jump to the label
 // is_instance or to the label is_not_instance.
 RawSubtypeTestCache* FlowGraphCompiler::GenerateInlineInstanceof(
     TokenPosition token_pos,
     const AbstractType& type,
     Label* is_instance_lbl,
     Label* is_not_instance_lbl) {
   __ Comment("InlineInstanceof");
@@ skipping 29 matching lines @@
 
 
 // If instanceof type test cannot be performed successfully at compile time and
 // therefore eliminated, optimize it by adding inlined tests for:
 // - NULL -> return type == Null (type is not Object or dynamic).
 // - Smi -> compile time subtype check (only if dst class is not parameterized).
 // - Class equality (only if class is not parameterized).
 // Inputs:
 // - A0: object.
 // - A1: instantiator type arguments or raw_null.
+// - A2: function type arguments or raw_null.
 // Returns:
 // - true or false in V0.
 void FlowGraphCompiler::GenerateInstanceOf(TokenPosition token_pos,
                                            intptr_t deopt_id,
                                            const AbstractType& type,
                                            LocationSummary* locs) {
   ASSERT(type.IsFinalized() && !type.IsMalformed() && !type.IsMalbounded());
   ASSERT(!type.IsObjectType() && !type.IsDynamicType());
 
-  // Preserve instantiator type arguments (A1).
-  __ addiu(SP, SP, Immediate(-1 * kWordSize));
-  __ sw(A1, Address(SP, 0 * kWordSize));
+  // Preserve instantiator type arguments (A1) and function type arguments (A2).
+  __ addiu(SP, SP, Immediate(-2 * kWordSize));
+  __ sw(A1, Address(SP, 1 * kWordSize));
+  __ sw(A2, Address(SP, 0 * kWordSize));
 
   Label is_instance, is_not_instance;
   // If type is instantiated and non-parameterized, we can inline code
   // checking whether the tested instance is a Smi.
   if (type.IsInstantiated()) {
     // A null object is only an instance of Null, Object, and dynamic.
     // Object and dynamic have already been checked above (if the type is
     // instantiated). So we can return false here if the instance is null,
     // unless the type is Null (and if the type is instantiated).
     // We can only inline this null check if the type is instantiated at compile
     // time, since an uninstantiated type at compile time could be Null, Object,
     // or dynamic at run time.
     __ BranchEqual(A0, Object::null_object(),
                    type.IsNullType() ? &is_instance : &is_not_instance);
   }
 
   // Generate inline instanceof test.
   SubtypeTestCache& test_cache = SubtypeTestCache::ZoneHandle(zone());
   test_cache =
       GenerateInlineInstanceof(token_pos, type, &is_instance, &is_not_instance);
 
   // test_cache is null if there is no fall-through.
   Label done;
   if (!test_cache.IsNull()) {
     // Generate runtime call.
-    // Load instantiator type arguments (A1).
-    __ lw(A1, Address(SP, 0 * kWordSize));
-
-    __ addiu(SP, SP, Immediate(-5 * kWordSize));
+    __ lw(A1, Address(SP, 1 * kWordSize));  // Get instantiator type args.
+    __ lw(A2, Address(SP, 0 * kWordSize));  // Get function type args.
+    __ addiu(SP, SP, Immediate(-6 * kWordSize));
     __ LoadObject(TMP, Object::null_object());
-    __ sw(TMP, Address(SP, 4 * kWordSize));  // Make room for the result.
-    __ sw(A0, Address(SP, 3 * kWordSize));   // Push the instance.
+    __ sw(TMP, Address(SP, 5 * kWordSize));  // Make room for the result.
+    __ sw(A0, Address(SP, 4 * kWordSize));   // Push the instance.
     __ LoadObject(TMP, type);
-    __ sw(TMP, Address(SP, 2 * kWordSize));  // Push the type.
-    __ sw(A1, Address(SP, 1 * kWordSize));   // Push type arguments.
+    __ sw(TMP, Address(SP, 3 * kWordSize));  // Push the type.
+    __ sw(A1, Address(SP, 2 * kWordSize));   // Push instantiator type args.
+    __ sw(A2, Address(SP, 1 * kWordSize));   // Push function type args.
     __ LoadUniqueObject(A0, test_cache);
     __ sw(A0, Address(SP, 0 * kWordSize));
-    GenerateRuntimeCall(token_pos, deopt_id, kInstanceofRuntimeEntry, 4, locs);
+    GenerateRuntimeCall(token_pos, deopt_id, kInstanceofRuntimeEntry, 5, locs);
     // Pop the parameters supplied to the runtime entry. The result of the
     // instanceof runtime call will be left as the result of the operation.
-    __ lw(T0, Address(SP, 4 * kWordSize));
-    __ addiu(SP, SP, Immediate(5 * kWordSize));
-    __ mov(V0, T0);
+    __ lw(V0, Address(SP, 5 * kWordSize));
+    __ addiu(SP, SP, Immediate(6 * kWordSize));
     __ b(&done);

[zra, 2017/04/07 17:36:31]

(optional) Branch delay slot can be used here.

[regis, 2017/04/11 04:23:08]

Done.

   }
   __ Bind(&is_not_instance);
   __ LoadObject(V0, Bool::Get(false));
   __ b(&done);
 
   __ Bind(&is_instance);
   __ LoadObject(V0, Bool::Get(true));
   __ Bind(&done);
-  // Remove instantiator type arguments (A1).
-  __ Drop(1);
+  // Remove instantiator type arguments and function type arguments.
+  __ Drop(2);
 }
 
 
 // Optimize assignable type check by adding inlined tests for:
 // - NULL -> return NULL.
 // - Smi -> compile time subtype check (only if dst class is not parameterized).
 // - Class equality (only if class is not parameterized).
 // Inputs:
 // - A0: instance being type checked.
 // - A1: instantiator type arguments or raw_null.
+// - A2: function type arguments or raw_null.
 // Returns:
 // - object in A0 for successful assignable check (or throws TypeError).
 // Clobbers: T0, T1, T2
 // Performance notes: positive checks must be quick, negative checks can be slow
 // as they throw an exception.
 void FlowGraphCompiler::GenerateAssertAssignable(TokenPosition token_pos,
                                                  intptr_t deopt_id,
                                                  const AbstractType& dst_type,
                                                  const String& dst_name,
                                                  LocationSummary* locs) {
   __ Comment("AssertAssignable");
   ASSERT(!token_pos.IsClassifying());
   ASSERT(!dst_type.IsNull());
   ASSERT(dst_type.IsFinalized());
   // Assignable check is skipped in FlowGraphBuilder, not here.
   ASSERT(dst_type.IsMalformedOrMalbounded() ||
          (!dst_type.IsDynamicType() && !dst_type.IsObjectType()));
-  // Preserve instantiator type arguments.
-  __ addiu(SP, SP, Immediate(-1 * kWordSize));
-  __ sw(A1, Address(SP, 0 * kWordSize));
+
+  // Preserve instantiator type arguments (A1) and function type arguments (A2).
+  __ addiu(SP, SP, Immediate(-2 * kWordSize));
+  __ sw(A1, Address(SP, 1 * kWordSize));
+  __ sw(A2, Address(SP, 0 * kWordSize));
 
   // A null object is always assignable and is returned as result.
   Label is_assignable, runtime_call;
 
   __ BranchEqual(A0, Object::null_object(), &is_assignable);
-  __ delay_slot()->sw(A1, Address(SP, 0 * kWordSize));
 
   // Generate throw new TypeError() if the type is malformed or malbounded.
   if (dst_type.IsMalformedOrMalbounded()) {
     __ addiu(SP, SP, Immediate(-4 * kWordSize));
     __ LoadObject(TMP, Object::null_object());
     __ sw(TMP, Address(SP, 3 * kWordSize));  // Make room for the result.
     __ sw(A0, Address(SP, 2 * kWordSize));   // Push the source object.
     __ LoadObject(TMP, dst_name);
     __ sw(TMP, Address(SP, 1 * kWordSize));  // Push the destination name.
     __ LoadObject(TMP, dst_type);
     __ sw(TMP, Address(SP, 0 * kWordSize));  // Push the destination type.
 
     GenerateRuntimeCall(token_pos, deopt_id, kBadTypeErrorRuntimeEntry, 3,
                         locs);
     // We should never return here.
     __ break_(0);
 
     __ Bind(&is_assignable);  // For a null object.
-    // Restore instantiator type arguments.
-    __ lw(A1, Address(SP, 0 * kWordSize));
-    __ addiu(SP, SP, Immediate(1 * kWordSize));
+    __ lw(A1, Address(SP, 1 * kWordSize));  // Restore instantiator type args.
+    __ lw(A2, Address(SP, 0 * kWordSize));  // Restore function type args.
+    __ addiu(SP, SP, Immediate(2 * kWordSize));
     return;
   }
 
   // Generate inline type check, linking to runtime call if not assignable.
   SubtypeTestCache& test_cache = SubtypeTestCache::ZoneHandle(zone());
   test_cache = GenerateInlineInstanceof(token_pos, dst_type, &is_assignable,
                                         &runtime_call);
 
   __ Bind(&runtime_call);
-  // Load instantiator type arguments (A1).
-  __ lw(A1, Address(SP, 0 * kWordSize));
+  __ lw(A1, Address(SP, 1 * kWordSize));  // Load instantiator type args.
+  __ lw(A2, Address(SP, 0 * kWordSize));  // Load function type args.
 
-  __ addiu(SP, SP, Immediate(-6 * kWordSize));
+  __ addiu(SP, SP, Immediate(-7 * kWordSize));
   __ LoadObject(TMP, Object::null_object());
-  __ sw(TMP, Address(SP, 5 * kWordSize));  // Make room for the result.
-  __ sw(A0, Address(SP, 4 * kWordSize));   // Push the source object.
+  __ sw(TMP, Address(SP, 6 * kWordSize));  // Make room for the result.
+  __ sw(A0, Address(SP, 5 * kWordSize));   // Push the source object.
   __ LoadObject(TMP, dst_type);
-  __ sw(TMP, Address(SP, 3 * kWordSize));  // Push the type of the destination.
-  __ sw(A1, Address(SP, 2 * kWordSize));   // Push type arguments.
+  __ sw(TMP, Address(SP, 4 * kWordSize));  // Push the type of the destination.
+  __ sw(A1, Address(SP, 3 * kWordSize));   // Push instantiator type args.
+  __ sw(A2, Address(SP, 2 * kWordSize));   // Push function type args.
   __ LoadObject(TMP, dst_name);
   __ sw(TMP, Address(SP, 1 * kWordSize));  // Push the name of the destination.
   __ LoadUniqueObject(T0, test_cache);
   __ sw(T0, Address(SP, 0 * kWordSize));
 
-  GenerateRuntimeCall(token_pos, deopt_id, kTypeCheckRuntimeEntry, 5, locs);
+  GenerateRuntimeCall(token_pos, deopt_id, kTypeCheckRuntimeEntry, 6, locs);
   // Pop the parameters supplied to the runtime entry. The result of the
   // type check runtime call is the checked value.
-  __ lw(A0, Address(SP, 5 * kWordSize));
-  __ addiu(SP, SP, Immediate(6 * kWordSize));
+  __ lw(A0, Address(SP, 6 * kWordSize));
+  __ addiu(SP, SP, Immediate(7 * kWordSize));
 
   __ Bind(&is_assignable);
-  // Restore instantiator type arguments.
-  __ lw(A1, Address(SP, 0 * kWordSize));
-  __ addiu(SP, SP, Immediate(1 * kWordSize));
+  __ lw(A1, Address(SP, 1 * kWordSize));  // Restore instantiator type args.
+  __ lw(A2, Address(SP, 0 * kWordSize));  // Restore function type args.
+  __ addiu(SP, SP, Immediate(2 * kWordSize));
 }
 
 
 void FlowGraphCompiler::EmitInstructionEpilogue(Instruction* instr) {
   if (is_optimizing()) return;
   Definition* defn = instr->AsDefinition();
   if ((defn != NULL) && defn->HasTemp()) {
     __ Push(defn->locs()->out(0).reg());
   }
 }
@@ skipping 1155 matching lines @@
   __ AddImmediate(SP, kDoubleSize);
 }
 
 
 #undef __
 
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_MIPS