VM: Don't emit usage counter and range feedback code and when optimizations are disabled.

runtime/vm/stub_code_x64.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_X64)
 
 #include "vm/assembler.h"
 #include "vm/compiler.h"
 #include "vm/dart_entry.h"
 #include "vm/flow_graph_compiler.h"
 #include "vm/heap.h"
 #include "vm/instructions.h"
 #include "vm/object_store.h"
 #include "vm/resolver.h"
 #include "vm/scavenger.h"
 #include "vm/stack_frame.h"
 #include "vm/stub_code.h"
 #include "vm/tags.h"
 
 #define __ assembler->
 
 namespace dart {
 
 DEFINE_FLAG(bool, inline_alloc, true, "Inline allocation of objects.");
 DEFINE_FLAG(bool, use_slow_path, false,
     "Set to true for debugging & verifying the slow paths.");
 DECLARE_FLAG(bool, trace_optimized_ic_calls);
+DECLARE_FLAG(int, optimization_counter_threshold);
 
 // Input parameters:
 //   RSP : points to return address.
 //   RSP + 8 : address of last argument in argument array.
 //   RSP + 8*R10 : address of first argument in argument array.
 //   RSP + 8*R10 + 8 : address of return value.
 //   RBX : address of the runtime function to call.
 //   R10 : number of arguments to the call.
 // Must preserve callee saved registers R12 and R13.
 void StubCode::GenerateCallToRuntimeStub(Assembler* assembler) {
@@ skipping 1168 matching lines @@
     __ popq(func_reg);     // Restore.
     __ LeaveStubFrame();
   }
   __ incl(FieldAddress(func_reg, Function::usage_counter_offset()));
 }
 
 
 // Loads function into 'temp_reg', preserves 'ic_reg'.
 void StubCode::GenerateUsageCounterIncrement(Assembler* assembler,
                                              Register temp_reg) {
-  Register ic_reg = RBX;
-  Register func_reg = temp_reg;
-  ASSERT(ic_reg != func_reg);
-  __ Comment("Increment function counter");
-  __ movq(func_reg, FieldAddress(ic_reg, ICData::owner_offset()));
-  __ incl(FieldAddress(func_reg, Function::usage_counter_offset()));
+  if (FLAG_optimization_counter_threshold >= 0) {
+    Register ic_reg = RBX;
+    Register func_reg = temp_reg;
+    ASSERT(ic_reg != func_reg);
+    __ Comment("Increment function counter");
+    __ movq(func_reg, FieldAddress(ic_reg, ICData::owner_offset()));
+    __ incl(FieldAddress(func_reg, Function::usage_counter_offset()));
+  }
 }
 
 
 // Note: RBX must be preserved.
 // Attempt a quick Smi operation for known operations ('kind'). The ICData
 // must have been primed with a Smi/Smi check that will be used for counting
 // the invocations.
 static void EmitFastSmiOp(Assembler* assembler,
                           Token::Kind kind,
                           intptr_t num_args,
@@ skipping 56 matching lines @@
       Immediate(reinterpret_cast<intptr_t>(Smi::New(kSmiCid)));
   __ cmpq(Address(R12, 0 * kWordSize), imm_smi_cid);
   __ j(NOT_EQUAL, &error, Assembler::kNearJump);
   __ cmpq(Address(R12, 1 * kWordSize), imm_smi_cid);
   __ j(EQUAL, &ok, Assembler::kNearJump);
   __ Bind(&error);
   __ Stop("Incorrect IC data");
   __ Bind(&ok);
 #endif
 
-  const intptr_t count_offset = ICData::CountIndexFor(num_args) * kWordSize;
-  // Update counter.
-  __ movq(R8, Address(R12, count_offset));
-  __ addq(R8, Immediate(Smi::RawValue(1)));
-  __ movq(R9, Immediate(Smi::RawValue(Smi::kMaxValue)));
-  __ cmovnoq(R9, R8);
-  __ StoreIntoSmiField(Address(R12, count_offset), R9);
+  if (FLAG_optimization_counter_threshold >= 0) {
+    const intptr_t count_offset = ICData::CountIndexFor(num_args) * kWordSize;
+    // Update counter.
+    __ movq(R8, Address(R12, count_offset));
+    __ addq(R8, Immediate(Smi::RawValue(1)));
+    __ movq(R9, Immediate(Smi::RawValue(Smi::kMaxValue)));
+    __ cmovnoq(R9, R8);
+    __ StoreIntoSmiField(Address(R12, count_offset), R9);
+  }
 
   __ ret();
 }
 
 
 // Generate inline cache check for 'num_args'.
 //  RBX: Inline cache data object.
 //  TOS(0): return address
 // Control flow:
 // - If receiver is null -> jump to IC miss.
@@ skipping 130 matching lines @@
     __ popq(RAX);
   }
   __ popq(RAX);  // Pop returned function object into RAX.
   __ popq(RBX);  // Restore IC data array.
   __ popq(R10);  // Restore arguments descriptor array.
   __ LeaveStubFrame();
   Label call_target_function;
   __ jmp(&call_target_function);
 
   __ Bind(&found);
-  __ Comment("Update caller's counter");
   // R12: Pointer to an IC data check group.
   const intptr_t target_offset = ICData::TargetIndexFor(num_args) * kWordSize;
   const intptr_t count_offset = ICData::CountIndexFor(num_args) * kWordSize;
   __ movq(RAX, Address(R12, target_offset));
 
-  // Update counter.
-  __ movq(R8, Address(R12, count_offset));
-  __ addq(R8, Immediate(Smi::RawValue(1)));
-  __ movq(R9, Immediate(Smi::RawValue(Smi::kMaxValue)));
-  __ cmovnoq(R9, R8);
-  __ StoreIntoSmiField(Address(R12, count_offset), R9);
+  if (FLAG_optimization_counter_threshold >= 0) {
+    // Update counter.
+    __ Comment("Update caller's counter");
+    __ movq(R8, Address(R12, count_offset));
+    __ addq(R8, Immediate(Smi::RawValue(1)));
+    __ movq(R9, Immediate(Smi::RawValue(Smi::kMaxValue)));
+    __ cmovnoq(R9, R8);
+    __ StoreIntoSmiField(Address(R12, count_offset), R9);
+  }
 
   __ Comment("Call target");
   __ Bind(&call_target_function);
   // RAX: Target function.
   Label is_compiled;
   __ movq(RCX, FieldAddress(RAX, Function::instructions_offset()));
   __ addq(RCX, Immediate(Instructions::HeaderSize() - kHeapObjectTag));
   if (range_collection_mode == kCollectRanges) {
     __ movq(R8, Address(RSP, + 1 * kWordSize));
     if (num_args == 2) {
@@ skipping 186 matching lines @@
   __ Bind(&done_stepping);
 
   // RBX: IC data object (preserved).
   __ movq(R12, FieldAddress(RBX, ICData::ic_data_offset()));
   // R12: ic_data_array with entries: target functions and count.
   __ leaq(R12, FieldAddress(R12, Array::data_offset()));
   // R12: points directly to the first ic data array element.
   const intptr_t target_offset = ICData::TargetIndexFor(0) * kWordSize;
   const intptr_t count_offset = ICData::CountIndexFor(0) * kWordSize;
 
-  // Increment count for this call.
-  __ movq(R8, Address(R12, count_offset));
-  __ addq(R8, Immediate(Smi::RawValue(1)));
-  __ movq(R9, Immediate(Smi::RawValue(Smi::kMaxValue)));
-  __ cmovnoq(R9, R8);
-  __ StoreIntoSmiField(Address(R12, count_offset), R9);
+  if (FLAG_optimization_counter_threshold >= 0) {
+    // Increment count for this call.
+    __ movq(R8, Address(R12, count_offset));
+    __ addq(R8, Immediate(Smi::RawValue(1)));
+    __ movq(R9, Immediate(Smi::RawValue(Smi::kMaxValue)));
+    __ cmovnoq(R9, R8);
+    __ StoreIntoSmiField(Address(R12, count_offset), R9);
+  }
 
   // Load arguments descriptor into R10.
   __ movq(R10, FieldAddress(RBX, ICData::arguments_descriptor_offset()));
 
   // Get function and call it, if possible.
   __ movq(RAX, Address(R12, target_offset));
   __ movq(RCX, FieldAddress(RAX, Function::instructions_offset()));
   // RCX: Target instructions.
   __ addq(RCX, Immediate(Instructions::HeaderSize() - kHeapObjectTag));
   __ jmp(RCX);
@@ skipping 409 matching lines @@
 
   __ movq(left, Address(RSP, 2 * kWordSize));
   __ movq(right, Address(RSP, 1 * kWordSize));
   GenerateIdenticalWithNumberCheckStub(assembler, left, right);
   __ ret();
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_X64