[Interpreter] Textual representation for runtime function IDs.

test/cctest/interpreter/bytecode-expectations-printer.cc

Index: test/cctest/interpreter/bytecode-expectations-printer.cc
diff --git a/test/cctest/interpreter/bytecode-expectations-printer.cc b/test/cctest/interpreter/bytecode-expectations-printer.cc
index d5e0456511528a13bf0f68c0d81c937fa06e44c8..d9a0952eae1786e23c3f4e68b73fa3f70132e2fd 100644
--- a/test/cctest/interpreter/bytecode-expectations-printer.cc
+++ b/test/cctest/interpreter/bytecode-expectations-printer.cc
@@ -13,6 +13,7 @@
 #include "src/base/logging.h"
 #include "src/base/smart-pointers.h"
 #include "src/compiler.h"
+#include "src/runtime/runtime.h"
 
 #include "src/interpreter/bytecode-array-iterator.h"
 #include "src/interpreter/bytecode-generator.h"
@@ -94,6 +95,12 @@ void BytecodeExpectationsPrinter::PrintEscapedString(
   }
 }
 
+namespace {
+i::Runtime::FunctionId IndexToFunctionId(int index) {
+  return static_cast<i::Runtime::FunctionId>(index);
+}
+}  // namespace
+
 void BytecodeExpectationsPrinter::PrintBytecodeOperand(
     std::ostream& stream, const BytecodeArrayIterator& bytecode_iter,
     const Bytecode& bytecode, int op_index, int parameter_count) const {
@@ -136,7 +143,11 @@ void BytecodeExpectationsPrinter::PrintBytecodeOperand(
   } else {
     stream << 'U' << size_tag << '(';
 
-    if (Bytecodes::IsImmediateOperandType(op_type)) {
+    if (op_index == 0 && Bytecodes::IsCallRuntime(bytecode)) {
+      int operand = bytecode_iter.GetIndexOperand(op_index);

[rmcilroy, 2016/02/23 17:53:23]

Could you add a DCHECK here that op_index is a Idx16 operand type (to catch the
case if we add another call runtime function that doesn't put the id as the
first operand).

[Stefano Sanfilippo, 2016/02/23 17:59:24]

Done.

+      stream << "Runtime::"
+             << i::Runtime::FunctionForId(IndexToFunctionId(operand))->name;
+    } else if (Bytecodes::IsImmediateOperandType(op_type)) {
       // We need a cast, otherwise the result is printed as char.
       stream << static_cast<int>(bytecode_iter.GetImmediateOperand(op_index));
     } else if (Bytecodes::IsRegisterCountOperandType(op_type)) {