Revert of [turbofan] ChangeFloat64ToTagged shouldn't canonicalize.

src/compiler/effect-control-linearizer.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 "src/compiler/effect-control-linearizer.h"
 
 #include "src/code-factory.h"
 #include "src/compiler/access-builder.h"
 #include "src/compiler/js-graph.h"
 #include "src/compiler/linkage.h"
@@ skipping 749 matching lines @@
   }
   NodeProperties::ReplaceUses(node, state.value, state.effect, state.control);
   *effect = state.effect;
   *control = state.control;
   return true;
 }
 
 EffectControlLinearizer::ValueEffectControl
 EffectControlLinearizer::LowerChangeFloat64ToTagged(Node* node, Node* effect,
                                                     Node* control) {
+  CheckForMinusZeroMode mode = CheckMinusZeroModeOf(node->op());
   Node* value = node->InputAt(0);
-  return AllocateHeapNumberWithValue(value, effect, control);
+
+  Node* value32 = graph()->NewNode(machine()->RoundFloat64ToInt32(), value);
+  Node* check_same = graph()->NewNode(
+      machine()->Float64Equal(), value,
+      graph()->NewNode(machine()->ChangeInt32ToFloat64(), value32));
+  Node* branch_same = graph()->NewNode(common()->Branch(), check_same, control);
+
+  Node* if_smi = graph()->NewNode(common()->IfTrue(), branch_same);
+  Node* vsmi;
+  Node* if_box = graph()->NewNode(common()->IfFalse(), branch_same);
+
+  if (mode == CheckForMinusZeroMode::kCheckForMinusZero) {
+    // Check if {value} is -0.
+    Node* check_zero = graph()->NewNode(machine()->Word32Equal(), value32,
+                                        jsgraph()->Int32Constant(0));
+    Node* branch_zero = graph()->NewNode(common()->Branch(BranchHint::kFalse),
+                                         check_zero, if_smi);
+
+    Node* if_zero = graph()->NewNode(common()->IfTrue(), branch_zero);
+    Node* if_notzero = graph()->NewNode(common()->IfFalse(), branch_zero);
+
+    // In case of 0, we need to check the high bits for the IEEE -0 pattern.
+    Node* check_negative = graph()->NewNode(
+        machine()->Int32LessThan(),
+        graph()->NewNode(machine()->Float64ExtractHighWord32(), value),
+        jsgraph()->Int32Constant(0));
+    Node* branch_negative = graph()->NewNode(
+        common()->Branch(BranchHint::kFalse), check_negative, if_zero);
+
+    Node* if_negative = graph()->NewNode(common()->IfTrue(), branch_negative);
+    Node* if_notnegative =
+        graph()->NewNode(common()->IfFalse(), branch_negative);
+
+    // We need to create a box for negative 0.
+    if_smi = graph()->NewNode(common()->Merge(2), if_notzero, if_notnegative);
+    if_box = graph()->NewNode(common()->Merge(2), if_box, if_negative);
+  }
+
+  // On 64-bit machines we can just wrap the 32-bit integer in a smi, for 32-bit
+  // machines we need to deal with potential overflow and fallback to boxing.
+  if (machine()->Is64()) {
+    vsmi = ChangeInt32ToSmi(value32);
+  } else {
+    Node* smi_tag = graph()->NewNode(machine()->Int32AddWithOverflow(), value32,
+                                     value32, if_smi);
+
+    Node* check_ovf =
+        graph()->NewNode(common()->Projection(1), smi_tag, if_smi);
+    Node* branch_ovf = graph()->NewNode(common()->Branch(BranchHint::kFalse),
+                                        check_ovf, if_smi);
+
+    Node* if_ovf = graph()->NewNode(common()->IfTrue(), branch_ovf);
+    if_box = graph()->NewNode(common()->Merge(2), if_ovf, if_box);
+
+    if_smi = graph()->NewNode(common()->IfFalse(), branch_ovf);
+    vsmi = graph()->NewNode(common()->Projection(0), smi_tag, if_smi);
+  }
+
+  // Allocate the box for the {value}.
+  ValueEffectControl box = AllocateHeapNumberWithValue(value, effect, if_box);
+
+  control = graph()->NewNode(common()->Merge(2), if_smi, box.control);
+  value = graph()->NewNode(common()->Phi(MachineRepresentation::kTagged, 2),
+                           vsmi, box.value, control);
+  effect =
+      graph()->NewNode(common()->EffectPhi(2), effect, box.effect, control);
+  return ValueEffectControl(value, effect, control);
 }
 
 EffectControlLinearizer::ValueEffectControl
 EffectControlLinearizer::LowerChangeBitToTagged(Node* node, Node* effect,
                                                 Node* control) {
   Node* value = node->InputAt(0);
 
   Node* branch = graph()->NewNode(common()->Branch(), value, control);
 
   Node* if_true = graph()->NewNode(common()->IfTrue(), branch);
@@ skipping 2612 matching lines @@
         isolate(), graph()->zone(), callable.descriptor(), 0, flags,
         Operator::kEliminatable);
     to_number_operator_.set(common()->Call(desc));
   }
   return to_number_operator_.get();
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8