Simplify type argument instantiation cache lookup by introducing an array

runtime/vm/stub_code_ia32.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"
 #if defined(TARGET_ARCH_IA32)
 
 #include "vm/assembler.h"
 #include "vm/compiler.h"
 #include "vm/dart_entry.h"
@@ skipping 1102 matching lines @@
   // The generated code is different if the class is parameterized.
   const bool is_cls_parameterized = cls.NumTypeArguments() > 0;
   ASSERT(!is_cls_parameterized ||
          (cls.type_arguments_field_offset() != Class::kNoTypeArguments));
   // kInlineInstanceSize is a constant used as a threshold for determining
   // when the object initialization should be done as a loop or as
   // straight line code.
   const int kInlineInstanceSize = 12;  // In words.
   const intptr_t instance_size = cls.instance_size();
   ASSERT(instance_size > 0);
-  Label slow_case_with_type_arguments;
+  if (is_cls_parameterized) {
+    __ movl(EDX, Address(ESP, kObjectTypeArgumentsOffset));
+    // EDX: instantiated type arguments.
+  }
   if (FLAG_inline_alloc && Heap::IsAllocatableInNewSpace(instance_size)) {
-    Label slow_case_reload_type_arguments;
-    if (is_cls_parameterized) {
-      __ movl(EDX, Address(ESP, kObjectTypeArgumentsOffset));
-      // EDX: instantiated type arguments.
-    }
+    Label slow_case;
     // Allocate the object and update top to point to
     // next object start and initialize the allocated object.
     // EDX: instantiated type arguments (if is_cls_parameterized).
     Heap* heap = Isolate::Current()->heap();
     __ movl(EAX, Address::Absolute(heap->TopAddress()));
     __ leal(EBX, Address(EAX, instance_size));
     // Check if the allocation fits into the remaining space.
     // EAX: potential new object start.
     // EBX: potential next object start.
     __ cmpl(EBX, Address::Absolute(heap->EndAddress()));
     if (FLAG_use_slow_path) {
-      __ jmp(&slow_case_with_type_arguments);
+      __ jmp(&slow_case);
     } else {
-      __ j(ABOVE_EQUAL, &slow_case_with_type_arguments);
+      __ j(ABOVE_EQUAL, &slow_case);
     }
     __ movl(Address::Absolute(heap->TopAddress()), EBX);
     __ UpdateAllocationStats(cls.id(), ECX);
 
     // EAX: new object start.
     // EBX: next object start.
     // EDX: new object type arguments (if is_cls_parameterized).
     // Set the tags.
     uword tags = 0;
     tags = RawObject::SizeTag::update(instance_size, tags);
@@ skipping 37 matching lines @@
     if (is_cls_parameterized) {
       // EDX: new object type arguments.
       // Set the type arguments in the new object.
       __ movl(Address(EAX, cls.type_arguments_field_offset()), EDX);
     }
     // Done allocating and initializing the instance.
     // EAX: new object.
     __ addl(EAX, Immediate(kHeapObjectTag));
     __ ret();
 
-    __ Bind(&slow_case_reload_type_arguments);
+    __ Bind(&slow_case);
   }
-  if (is_cls_parameterized) {
-    __ movl(EDX, Address(ESP, kObjectTypeArgumentsOffset));
-  }
-  __ Bind(&slow_case_with_type_arguments);
   // If is_cls_parameterized:
   // EDX: new object type arguments.
   // Create a stub frame as we are pushing some objects on the stack before
   // calling into the runtime.
   __ EnterStubFrame();
   __ pushl(raw_null);  // Setup space on stack for return value.
   __ PushObject(cls);  // Push class of object to be allocated.
   if (is_cls_parameterized) {
     __ pushl(EDX);  // Push type arguments of object to be allocated.
   } else {
@@ skipping 904 matching lines @@
   const Register temp = ECX;
   __ movl(left, Address(ESP, 2 * kWordSize));
   __ movl(right, Address(ESP, 1 * kWordSize));
   GenerateIdenticalWithNumberCheckStub(assembler, left, right, temp);
   __ ret();
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_IA32