[Interpreter] Enable runtime profiler support for Ignition.

src/interpreter/interpreter-assembler.cc

Index: src/interpreter/interpreter-assembler.cc
diff --git a/src/interpreter/interpreter-assembler.cc b/src/interpreter/interpreter-assembler.cc
index d19e8ac7f9262211e2abebd83269f1eca282b7f2..70bc9be2db39711d8144b2336bd1cfb919fcc4f5 100644
--- a/src/interpreter/interpreter-assembler.cc
+++ b/src/interpreter/interpreter-assembler.cc
@@ -10,6 +10,7 @@
 #include "src/frames.h"
 #include "src/interface-descriptors.h"
 #include "src/interpreter/bytecodes.h"
+#include "src/interpreter/interpreter.h"
 #include "src/machine-type.h"
 #include "src/macro-assembler.h"
 #include "src/zone.h"
@@ -371,6 +372,36 @@ Node* InterpreterAssembler::CallRuntimeN(Node* function_id, Node* context,
                   first_arg, function_entry, result_size);
 }
 
+void InterpreterAssembler::UpdateProfilingCount(Node* weight) {
+  CodeStubAssembler::Label ok(this);
+  CodeStubAssembler::Label interrupt_check(this);
+  CodeStubAssembler::Label end(this);
+  Node* counter_offset =
+      IntPtrConstant(BytecodeArray::kProfilingCountOffset - kHeapObjectTag);
+
+  // Decrement counter and check if it reaches zero.
+  Node* old_count =
+      Load(MachineType::Int32(), BytecodeArrayTaggedPointer(), counter_offset);
+  Node* new_count = Int32Add(old_count, weight);
+  Node* condition = Int32GreaterThanOrEqual(new_count, Int32Constant(0));
+  Branch(condition, &ok, &interrupt_check);
+
+  // Perform interrupt and reset counter.
+  Bind(&interrupt_check);
+  CallRuntime(Runtime::kInterrupt, GetContext());
+  StoreNoWriteBarrier(MachineRepresentation::kWord32,
+                      BytecodeArrayTaggedPointer(), counter_offset,
+                      Int32Constant(Interpreter::InterruptBudget()));
+  Goto(&end);
+
+  // Update counter.
+  Bind(&ok);
+  StoreNoWriteBarrier(MachineRepresentation::kWord32,
+                      BytecodeArrayTaggedPointer(), counter_offset, new_count);
+  Goto(&end);
+  Bind(&end);
+}
+
 Node* InterpreterAssembler::Advance(int delta) {
   return IntPtrAdd(BytecodeOffset(), Int32Constant(delta));
 }
@@ -379,7 +410,10 @@ Node* InterpreterAssembler::Advance(Node* delta) {
   return IntPtrAdd(BytecodeOffset(), delta);
 }
 
-void InterpreterAssembler::Jump(Node* delta) { DispatchTo(Advance(delta)); }
+void InterpreterAssembler::Jump(Node* delta) {
+  UpdateProfilingCount(delta);
+  DispatchTo(Advance(delta));
+}
 
 void InterpreterAssembler::JumpConditional(Node* condition, Node* delta) {
   CodeStubAssembler::Label match(this);
@@ -387,7 +421,7 @@ void InterpreterAssembler::JumpConditional(Node* condition, Node* delta) {
 
   Branch(condition, &match, &no_match);
   Bind(&match);
-  DispatchTo(Advance(delta));
+  Jump(delta);
   Bind(&no_match);
   Dispatch();
 }
@@ -429,6 +463,15 @@ void InterpreterAssembler::InterpreterReturn() {
   if (FLAG_trace_ignition) {
     TraceBytecode(Runtime::kInterpreterTraceBytecodeExit);
   }
+
+  // TODO(rmcilroy): Deal with self optimization of primitive functions.
+  // Update profiling count by -BytecodeOffset to simulate backedge to start of
+  // function.
+  Node* profiling_weight =
+      Int32Sub(Int32Constant(kHeapObjectTag + BytecodeArray::kHeaderSize),
+               BytecodeOffset());
+  UpdateProfilingCount(profiling_weight);
+
   InterpreterDispatchDescriptor descriptor(isolate());
   Node* exit_trampoline_code_object =
       HeapConstant(isolate()->builtins()->InterpreterExitTrampoline());