[turbofan] Introduce TruncateTaggedToWord32 simplified operator.

test/unittests/compiler/instruction-selector-unittest.cc

 // Copyright 2014 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 "test/unittests/compiler/instruction-selector-unittest.h"
 
 #include "src/code-factory.h"
 #include "src/compiler/graph.h"
 #include "src/compiler/schedule.h"
 #include "src/flags.h"
@@ skipping 181 matching lines @@
   EXPECT_EQ(InstructionOperand::CONSTANT, s[0]->OutputAt(0)->kind());
   EXPECT_EQ(0, s.ToInt32(s[0]->OutputAt(0)));
   EXPECT_EQ(kArchRet, s[1]->arch_opcode());
   EXPECT_EQ(1U, s[1]->InputCount());
 }
 
 
 // -----------------------------------------------------------------------------
 // Conversions.
 
-
-TARGET_TEST_F(InstructionSelectorTest, TruncateFloat64ToInt32WithParameter) {
+TARGET_TEST_F(InstructionSelectorTest, TruncateFloat64ToWord32WithParameter) {
   StreamBuilder m(this, MachineType::Int32(), MachineType::Float64());
-  m.Return(
-      m.TruncateFloat64ToInt32(TruncationMode::kJavaScript, m.Parameter(0)));
+  m.Return(m.TruncateFloat64ToWord32(m.Parameter(0)));
   Stream s = m.Build(kAllInstructions);
   ASSERT_EQ(4U, s.size());
   EXPECT_EQ(kArchNop, s[0]->arch_opcode());
   EXPECT_EQ(kArchTruncateDoubleToI, s[1]->arch_opcode());
   EXPECT_EQ(1U, s[1]->InputCount());
   EXPECT_EQ(1U, s[1]->OutputCount());
   EXPECT_EQ(kArchRet, s[2]->arch_opcode());
 }
 
 
@@ skipping 406 matching lines @@
   EXPECT_EQ(s.ToVreg(context2), s.ToVreg(call_instr->InputAt(14)));
   // Continuation.
 
   EXPECT_EQ(kArchRet, s[index++]->arch_opcode());
   EXPECT_EQ(index, s.size());
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8