[Interpreter] Replace BytecodeRegisterAllocator with a simple bump pointer.

test/cctest/interpreter/test-interpreter.cc

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <tuple>
 
 #include "src/v8.h"
 
 #include "src/execution.h"
 #include "src/handles.h"
@@ skipping 1218 matching lines @@
   int slot_index = vector->GetIndex(slot);
   int call_slot_index = -1;
   call_slot_index = vector->GetIndex(call_slot);
 
   Handle<i::String> name = factory->NewStringFromAsciiChecked("func");
   name = factory->string_table()->LookupString(isolate, name);
 
   // Check with no args.
   {
     BytecodeArrayBuilder builder(isolate, handles.main_zone(), 1, 0, 1);
+    Register reg = builder.register_allocator()->NewRegister();
+    RegisterList args = builder.register_allocator()->NewRegisterList(1);
+    builder.LoadNamedProperty(builder.Parameter(0), name, slot_index)
+        .StoreAccumulatorInRegister(reg)
+        .MoveRegister(builder.Parameter(0), args[0]);
 
-    builder.LoadNamedProperty(builder.Parameter(0), name, slot_index)
-        .StoreAccumulatorInRegister(Register(0));
-
-    builder.Call(Register(0), builder.Parameter(0), 1, call_slot_index,
-                 tail_call_mode);
+    builder.Call(reg, args, call_slot_index, tail_call_mode);
 
     builder.Return();
     Handle<BytecodeArray> bytecode_array = builder.ToBytecodeArray(isolate);
 
     InterpreterTester tester(isolate, bytecode_array, vector);
     auto callable = tester.GetCallable<Handle<Object>>();
 
     Handle<Object> object = InterpreterTester::NewObject(
         "new (function Obj() { this.func = function() { return 0x265; }})()");
     Handle<Object> return_val = callable(object).ToHandleChecked();
     CHECK_EQ(Smi::cast(*return_val), Smi::FromInt(0x265));
   }
 
   // Check that receiver is passed properly.
   {
     BytecodeArrayBuilder builder(isolate, handles.main_zone(), 1, 0, 1);
-
+    Register reg = builder.register_allocator()->NewRegister();
+    RegisterList args = builder.register_allocator()->NewRegisterList(1);
     builder.LoadNamedProperty(builder.Parameter(0), name, slot_index)
-        .StoreAccumulatorInRegister(Register(0));
-    builder.Call(Register(0), builder.Parameter(0), 1, call_slot_index,
-                 tail_call_mode);
+        .StoreAccumulatorInRegister(reg)
+        .MoveRegister(builder.Parameter(0), args[0]);
+    builder.Call(reg, args, call_slot_index, tail_call_mode);
     builder.Return();
     Handle<BytecodeArray> bytecode_array = builder.ToBytecodeArray(isolate);
 
     InterpreterTester tester(isolate, bytecode_array, vector);
     auto callable = tester.GetCallable<Handle<Object>>();
 
     Handle<Object> object = InterpreterTester::NewObject(
         "new (function Obj() {"
         "  this.val = 1234;"
         "  this.func = function() { return this.val; };"
         "})()");
     Handle<Object> return_val = callable(object).ToHandleChecked();
     CHECK_EQ(Smi::cast(*return_val), Smi::FromInt(1234));
   }
 
   // Check with two parameters (+ receiver).
   {
     BytecodeArrayBuilder builder(isolate, handles.main_zone(), 1, 0, 4);
+    Register reg = builder.register_allocator()->NewRegister();
+    RegisterList args = builder.register_allocator()->NewRegisterList(3);
 
     builder.LoadNamedProperty(builder.Parameter(0), name, slot_index)
-        .StoreAccumulatorInRegister(Register(0))
+        .StoreAccumulatorInRegister(reg)
         .LoadAccumulatorWithRegister(builder.Parameter(0))
-        .StoreAccumulatorInRegister(Register(1))
+        .StoreAccumulatorInRegister(args[0])
         .LoadLiteral(Smi::FromInt(51))
-        .StoreAccumulatorInRegister(Register(2))
+        .StoreAccumulatorInRegister(args[1])
         .LoadLiteral(Smi::FromInt(11))
-        .StoreAccumulatorInRegister(Register(3));
+        .StoreAccumulatorInRegister(args[2]);
 
-    builder.Call(Register(0), Register(1), 3, call_slot_index, tail_call_mode);
+    builder.Call(reg, args, call_slot_index, tail_call_mode);
 
     builder.Return();
 
     Handle<BytecodeArray> bytecode_array = builder.ToBytecodeArray(isolate);
 
     InterpreterTester tester(isolate, bytecode_array, vector);
     auto callable = tester.GetCallable<Handle<Object>>();
 
     Handle<Object> object = InterpreterTester::NewObject(
         "new (function Obj() { "
         "  this.func = function(a, b) { return a - b; }"
         "})()");
     Handle<Object> return_val = callable(object).ToHandleChecked();
     CHECK(return_val->SameValue(Smi::FromInt(40)));
   }
 
   // Check with 10 parameters (+ receiver).
   {
     BytecodeArrayBuilder builder(isolate, handles.main_zone(), 1, 0, 12);
+    Register reg = builder.register_allocator()->NewRegister();
+    RegisterList args = builder.register_allocator()->NewRegisterList(11);
 
     builder.LoadNamedProperty(builder.Parameter(0), name, slot_index)
-        .StoreAccumulatorInRegister(Register(0))
+        .StoreAccumulatorInRegister(reg)
         .LoadAccumulatorWithRegister(builder.Parameter(0))
-        .StoreAccumulatorInRegister(Register(1))
+        .StoreAccumulatorInRegister(args[0])
         .LoadLiteral(factory->NewStringFromAsciiChecked("a"))
-        .StoreAccumulatorInRegister(Register(2))
+        .StoreAccumulatorInRegister(args[1])
         .LoadLiteral(factory->NewStringFromAsciiChecked("b"))
-        .StoreAccumulatorInRegister(Register(3))
+        .StoreAccumulatorInRegister(args[2])
         .LoadLiteral(factory->NewStringFromAsciiChecked("c"))
-        .StoreAccumulatorInRegister(Register(4))
+        .StoreAccumulatorInRegister(args[3])
         .LoadLiteral(factory->NewStringFromAsciiChecked("d"))
-        .StoreAccumulatorInRegister(Register(5))
+        .StoreAccumulatorInRegister(args[4])
         .LoadLiteral(factory->NewStringFromAsciiChecked("e"))
-        .StoreAccumulatorInRegister(Register(6))
+        .StoreAccumulatorInRegister(args[5])
         .LoadLiteral(factory->NewStringFromAsciiChecked("f"))
-        .StoreAccumulatorInRegister(Register(7))
+        .StoreAccumulatorInRegister(args[6])
         .LoadLiteral(factory->NewStringFromAsciiChecked("g"))
-        .StoreAccumulatorInRegister(Register(8))
+        .StoreAccumulatorInRegister(args[7])
         .LoadLiteral(factory->NewStringFromAsciiChecked("h"))
-        .StoreAccumulatorInRegister(Register(9))
+        .StoreAccumulatorInRegister(args[8])
         .LoadLiteral(factory->NewStringFromAsciiChecked("i"))
-        .StoreAccumulatorInRegister(Register(10))
+        .StoreAccumulatorInRegister(args[9])
         .LoadLiteral(factory->NewStringFromAsciiChecked("j"))
-        .StoreAccumulatorInRegister(Register(11));
+        .StoreAccumulatorInRegister(args[10]);
 
-    builder.Call(Register(0), Register(1), 11, call_slot_index, tail_call_mode);
+    builder.Call(reg, args, call_slot_index, tail_call_mode);
 
     builder.Return();
 
     Handle<BytecodeArray> bytecode_array = builder.ToBytecodeArray(isolate);
 
     InterpreterTester tester(isolate, bytecode_array, vector);
     auto callable = tester.GetCallable<Handle<Object>>();
 
     Handle<Object> object = InterpreterTester::NewObject(
         "new (function Obj() { "
@@ skipping 754 matching lines @@
     CHECK_EQ(strcmp(&actual[0], typeof_vals[i].second), 0);
   }
 }
 
 
 TEST(InterpreterCallRuntime) {
   HandleAndZoneScope handles;
   Isolate* isolate = handles.main_isolate();
 
   BytecodeArrayBuilder builder(isolate, handles.main_zone(), 1, 0, 2);
+  RegisterList args = builder.register_allocator()->NewRegisterList(2);
 
   builder.LoadLiteral(Smi::FromInt(15))
-      .StoreAccumulatorInRegister(Register(0))
+      .StoreAccumulatorInRegister(args[0])
       .LoadLiteral(Smi::FromInt(40))
-      .StoreAccumulatorInRegister(Register(1))
-      .CallRuntime(Runtime::kAdd, Register(0), 2)
+      .StoreAccumulatorInRegister(args[1])
+      .CallRuntime(Runtime::kAdd, args)
       .Return();
   Handle<BytecodeArray> bytecode_array = builder.ToBytecodeArray(isolate);
 
   InterpreterTester tester(isolate, bytecode_array);
   auto callable = tester.GetCallable<>();
 
   Handle<Object> return_val = callable().ToHandleChecked();
   CHECK_EQ(Smi::cast(*return_val), Smi::FromInt(55));
 }
 
 TEST(InterpreterInvokeIntrinsic) {
   HandleAndZoneScope handles;
   Isolate* isolate = handles.main_isolate();
 
   BytecodeArrayBuilder builder(isolate, handles.main_zone(), 1, 0, 2);
 
   builder.LoadLiteral(Smi::FromInt(15))
       .StoreAccumulatorInRegister(Register(0))
-      .CallRuntime(Runtime::kInlineIsArray, Register(0), 1)
+      .CallRuntime(Runtime::kInlineIsArray, Register(0))
       .Return();
   Handle<BytecodeArray> bytecode_array = builder.ToBytecodeArray(isolate);
 
   InterpreterTester tester(isolate, bytecode_array);
   auto callable = tester.GetCallable<>();
 
   Handle<Object> return_val = callable().ToHandleChecked();
   CHECK(return_val->IsBoolean());
   CHECK_EQ(return_val->BooleanValue(), false);
 }
@@ skipping 2655 matching lines @@
     auto callable = tester.GetCallable<>();
 
     Handle<i::Object> return_value = callable().ToHandleChecked();
     CHECK(return_value->SameValue(*tests[i].second));
   }
 }
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8