[Interpreter] Add support for loading literals from the constant pool.

test/unittests/compiler/interpreter-assembler-unittest.cc

Index: test/unittests/compiler/interpreter-assembler-unittest.cc
diff --git a/test/unittests/compiler/interpreter-assembler-unittest.cc b/test/unittests/compiler/interpreter-assembler-unittest.cc
index 9fdb7f51e617441698c30e02b0572e86c8e6eb42..b7e15a98ca02498eefe234eff55914e78b2712cd 100644
--- a/test/unittests/compiler/interpreter-assembler-unittest.cc
+++ b/test/unittests/compiler/interpreter-assembler-unittest.cc
@@ -177,6 +177,9 @@ TARGET_TEST_F(InterpreterAssemblerTest, BytecodeOperand) {
     int number_of_operands = interpreter::Bytecodes::NumberOfOperands(bytecode);
     for (int i = 0; i < number_of_operands; i++) {
       switch (interpreter::Bytecodes::GetOperandType(bytecode, i)) {
+        case interpreter::OperandType::kIdx:
+          EXPECT_THAT(m.BytecodeOperandIdx(i), m.IsBytecodeOperand(i));
+          break;
         case interpreter::OperandType::kImm8:
           EXPECT_THAT(m.BytecodeOperandImm8(i),
                       m.IsBytecodeOperandSignExtended(i));
@@ -266,6 +269,25 @@ TARGET_TEST_F(InterpreterAssemblerTest, SmiTag) {
 }
 
 
+TARGET_TEST_F(InterpreterAssemblerTest, LoadConstantPoolEntry) {
+  TRACED_FOREACH(interpreter::Bytecode, bytecode, kBytecodes) {
+    InterpreterAssemblerForTest m(this, bytecode);
+    Node* index = m.Int32Constant(2);
+    Node* load_constant = m.LoadConstantPoolEntry(index);
+    Matcher<Node*> constant_pool_matcher = m.IsLoad(
+        kMachAnyTagged,
+        IsParameter(Linkage::kInterpreterBytecodeArrayParameter),
+        IsIntPtrConstant(BytecodeArray::kConstantPoolOffset - kHeapObjectTag));
+    EXPECT_THAT(
+        load_constant,
+        m.IsLoad(kMachAnyTagged, constant_pool_matcher,
+                 IsIntPtrAdd(
+                     IsIntPtrConstant(FixedArray::kHeaderSize - kHeapObjectTag),
+                     IsWordShl(index, IsInt32Constant(kPointerSizeLog2)))));
+  }
+}
+
+
 TARGET_TEST_F(InterpreterAssemblerTest, LoadContextSlot) {
   TRACED_FOREACH(interpreter::Bytecode, bytecode, kBytecodes) {
     InterpreterAssemblerForTest m(this, bytecode);