Revert of [turbofan] Remove left-over change bits from ChangeLowering.

src/compiler/change-lowering.cc

Index: src/compiler/change-lowering.cc
diff --git a/src/compiler/change-lowering.cc b/src/compiler/change-lowering.cc
index d2afdf5b4e6ebb04d820a2b69fca6d546598e712..4b77ea1dd09aa153cdcff64c7cb267ea48c6da0e 100644
--- a/src/compiler/change-lowering.cc
+++ b/src/compiler/change-lowering.cc
@@ -4,12 +4,14 @@
 
 #include "src/compiler/change-lowering.h"
 
+#include "src/address-map.h"
+#include "src/code-factory.h"
 #include "src/compiler/js-graph.h"
 #include "src/compiler/linkage.h"
 #include "src/compiler/machine-operator.h"
 #include "src/compiler/node-properties.h"
+#include "src/compiler/operator-properties.h"
 #include "src/compiler/simplified-operator.h"
-#include "src/conversions-inl.h"
 
 namespace v8 {
 namespace internal {
@@ -19,7 +21,16 @@
 
 
 Reduction ChangeLowering::Reduce(Node* node) {
+  Node* control = graph()->start();
   switch (node->opcode()) {
+    case IrOpcode::kChangeBitToBool:
+      return ReduceChangeBitToBool(node->InputAt(0), control);
+    case IrOpcode::kChangeBoolToBit:
+      return ReduceChangeBoolToBit(node->InputAt(0));
+    case IrOpcode::kChangeInt31ToTagged:
+      return ReduceChangeInt31ToTagged(node->InputAt(0), control);
+    case IrOpcode::kChangeTaggedSignedToInt32:
+      return ReduceChangeTaggedSignedToInt32(node->InputAt(0));
     case IrOpcode::kLoadField:
       return ReduceLoadField(node);
     case IrOpcode::kStoreField:
@@ -30,11 +41,57 @@
       return ReduceStoreElement(node);
     case IrOpcode::kAllocate:
       return ReduceAllocate(node);
+    case IrOpcode::kObjectIsSmi:
+      return ReduceObjectIsSmi(node);
     default:
       return NoChange();
   }
   UNREACHABLE();
   return NoChange();
+}
+
+Node* ChangeLowering::SmiShiftBitsConstant() {
+  return jsgraph()->IntPtrConstant(kSmiShiftSize + kSmiTagSize);
+}
+
+Node* ChangeLowering::ChangeInt32ToSmi(Node* value) {
+  if (machine()->Is64()) {
+    value = graph()->NewNode(machine()->ChangeInt32ToInt64(), value);
+  }
+  return graph()->NewNode(machine()->WordShl(), value, SmiShiftBitsConstant());
+}
+
+Node* ChangeLowering::ChangeSmiToWord32(Node* value) {
+  value = graph()->NewNode(machine()->WordSar(), value, SmiShiftBitsConstant());
+  if (machine()->Is64()) {
+    value = graph()->NewNode(machine()->TruncateInt64ToInt32(), value);
+  }
+  return value;
+}
+
+
+Node* ChangeLowering::ChangeUint32ToFloat64(Node* value) {
+  return graph()->NewNode(machine()->ChangeUint32ToFloat64(), value);
+}
+
+Reduction ChangeLowering::ReduceChangeBitToBool(Node* value, Node* control) {
+  return Replace(
+      graph()->NewNode(common()->Select(MachineRepresentation::kTagged), value,
+                       jsgraph()->TrueConstant(), jsgraph()->FalseConstant()));
+}
+
+Reduction ChangeLowering::ReduceChangeBoolToBit(Node* value) {
+  return Replace(graph()->NewNode(machine()->WordEqual(), value,
+                                  jsgraph()->TrueConstant()));
+}
+
+Reduction ChangeLowering::ReduceChangeInt31ToTagged(Node* value,
+                                                    Node* control) {
+  return Replace(ChangeInt32ToSmi(value));
+}
+
+Reduction ChangeLowering::ReduceChangeTaggedSignedToInt32(Node* value) {
+  return Replace(ChangeSmiToWord32(value));
 }
 
 namespace {
@@ -148,6 +205,15 @@
   return Changed(node);
 }
 
+Reduction ChangeLowering::ReduceObjectIsSmi(Node* node) {
+  node->ReplaceInput(0,
+                     graph()->NewNode(machine()->WordAnd(), node->InputAt(0),
+                                      jsgraph()->IntPtrConstant(kSmiTagMask)));
+  node->AppendInput(graph()->zone(), jsgraph()->IntPtrConstant(kSmiTag));
+  NodeProperties::ChangeOp(node, machine()->WordEqual());
+  return Changed(node);
+}
+
 Isolate* ChangeLowering::isolate() const { return jsgraph()->isolate(); }