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

runtime/vm/code_patcher_x64.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_X64.
 #if defined(TARGET_ARCH_X64)
 
 #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 {
 
-// A Dart instance call passes the ic-data in RBX.
-// The expected pattern of a dart instance call:
+// The expected pattern of a Dart unoptimized call (static and instance):
 //  00: 48 bb imm64  mov RBX, ic-data
 //  10: 49 bb imm64  mov R11, target_address
 //  20: 41 ff d3   call R11
 //  23 <- return address
-class InstanceCall : public ValueObject {
+class UnoptimizedCall : public ValueObject {
  public:
-  explicit InstanceCall(uword return_address)
+  explicit UnoptimizedCall(uword return_address)
       : start_(return_address - kCallPatternSize) {
     ASSERT(IsValid(return_address));
     ASSERT((kCallPatternSize - 10) == Assembler::kCallExternalLabelSize);
   }
 
   static const int kCallPatternSize = 23;
 
   static bool IsValid(uword return_address) {
     uint8_t* code_bytes =
         reinterpret_cast<uint8_t*>(return_address - kCallPatternSize);
@@ skipping 12 matching lines @@
   }
 
   void set_target(uword target) const {
     uword* target_addr = reinterpret_cast<uword*>(start_ + 10 + 2);
     *target_addr = target;
     CPU::FlushICache(start_ + 10, 2 + 8);
   }
 
  private:
   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 R10, arguments_descriptor_array (10 bytes) (optional in polym. calls)
 //  mov R11, target_address (10 bytes)
 //  call R11  (3 bytes)
 //  <- return address
 class StaticCall : public ValueObject {
  public:
   explicit StaticCall(uword return_address)
       : start_(return_address - kCallPatternSize) {
     ASSERT(IsValid(return_address));
@@ skipping 103 matching lines @@
   }
   return call.target();
 }
 
 
 intptr_t CodePatcher::InstanceCallSizeInBytes() {
   return InstanceCall::kCallPatternSize;
 }
 
 
+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);
+}
+
+
 void CodePatcher::InsertCallAt(uword start, uword target) {
   // The inserted call should not overlap the lazy deopt jump code.
   ASSERT(start + ShortCallPattern::InstructionLength() <= target);
   *reinterpret_cast<uint8_t*>(start) = 0xE8;
   ShortCallPattern call(start);
   call.SetTargetAddress(target);
   CPU::FlushICache(start, ShortCallPattern::InstructionLength());
 }
 
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_X64