Change static calls in unoptimized code to always call via a stub. Using ICData, the call count of …

runtime/vm/code_patcher_ia32.cc

 // Copyright (c) 2012, 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_IA32.
 #if defined(TARGET_ARCH_IA32)
 
 #include "vm/assembler.h"
 #include "vm/code_patcher.h"
 #include "vm/cpu.h"
 #include "vm/dart_entry.h"
 #include "vm/instructions.h"
 #include "vm/object.h"
 #include "vm/raw_object.h"
 
 namespace dart {
 
-// The expected pattern of a dart instance call:
+// The expected pattern of a Dart unoptimized call (static and instance):
 //  mov ECX, ic-data
-//  call target_address
+//  call target_address (stub)
 //  <- return address
-class InstanceCall : public ValueObject {
+class UnoptimizedCall : public ValueObject {
  public:
-  explicit InstanceCall(uword return_address)
+  explicit UnoptimizedCall(uword return_address)
       : start_(return_address - (kNumInstructions * kInstructionSize)) {
     ASSERT(IsValid(return_address));
     ASSERT(kInstructionSize == Assembler::kCallExternalLabelSize);
   }
 
   static bool IsValid(uword return_address) {
     uint8_t* code_bytes =
         reinterpret_cast<uint8_t*>(
             return_address - (kNumInstructions * kInstructionSize));
     return (code_bytes[0] == 0xB9) &&
@@ skipping 22 matching lines @@
  private:
   uword return_address() const {
     return start_ + kNumInstructions * kInstructionSize;
   }
 
   uword call_address() const {
     return start_ + 1 * kInstructionSize;
   }
 
   uword start_;
+  DISALLOW_IMPLICIT_CONSTRUCTORS(UnoptimizedCall);
+};
+
+
+class InstanceCall : public UnoptimizedCall {
+ public:
+  explicit InstanceCall(uword return_address)
+      : UnoptimizedCall(return_address) {
+#if defined(DEBUG)
+    ICData& test_ic_data = ICData::Handle();
+    test_ic_data ^= ic_data();
+    ASSERT(test_ic_data.num_args_tested() > 0);
+#endif  // DEBUG
+  }
+
+ private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(InstanceCall);
 };
 
 
+class UnoptimizedStaticCall : public UnoptimizedCall {
+ public:
+  explicit UnoptimizedStaticCall(uword return_address)
+      : UnoptimizedCall(return_address) {
+#if defined(DEBUG)
+    ICData& test_ic_data = ICData::Handle();
+    test_ic_data ^= ic_data();
+    ASSERT(test_ic_data.num_args_tested() == 0);
+#endif  // DEBUG
+  }
+
+ private:
+  DISALLOW_IMPLICIT_CONSTRUCTORS(UnoptimizedStaticCall);
+};
+
+
 // The expected pattern of a dart static call:
 //  mov EDX, arguments_descriptor_array (optional in polymorphic calls)
 //  call target_address
 //  <- return address
 class StaticCall : public ValueObject {
  public:
   explicit StaticCall(uword return_address)
       : start_(return_address - (kNumInstructions * kInstructionSize)) {
     ASSERT(IsValid(return_address));
     ASSERT(kInstructionSize == Assembler::kCallExternalLabelSize);
@@ skipping 123 matching lines @@
                                      ICData* ic_data) {
   ASSERT(code.ContainsInstructionAt(return_address));
   InstanceCall call(return_address);
   if (ic_data != NULL) {
     *ic_data ^= call.ic_data();
   }
   return call.target();
 }
 
 
+RawFunction* CodePatcher::GetUnoptimizedStaticCallTargetAt(
+    uword return_address, const Code& code) {
+  ASSERT(code.ContainsInstructionAt(return_address));
+  UnoptimizedStaticCall static_call(return_address);
+  ICData& ic_data = ICData::Handle();
+  ic_data ^= static_call.ic_data();
+  return ic_data.GetTargetAt(0);
+}
+
+
 intptr_t CodePatcher::InstanceCallSizeInBytes() {
   return InstanceCall::kNumInstructions * InstanceCall::kInstructionSize;
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_IA32