[turbofan] Address the useless overflow bit materialization.

src/compiler/int64-lowering.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 "src/compiler/int64-lowering.h"
 #include "src/compiler/common-operator.h"
 #include "src/compiler/diamond.h"
 #include "src/compiler/graph.h"
 #include "src/compiler/linkage.h"
 #include "src/compiler/machine-operator.h"
@@ skipping 225 matching lines @@
           (descriptor->ReturnCount() == 1 &&
            descriptor->GetReturnType(0) == MachineType::Int64())) {
         // We have to adjust the call descriptor.
         const Operator* op = common()->Call(
             wasm::ModuleEnv::GetI32WasmCallDescriptor(zone(), descriptor));
         NodeProperties::ChangeOp(node, op);
       }
       if (descriptor->ReturnCount() == 1 &&
           descriptor->GetReturnType(0) == MachineType::Int64()) {
         // We access the additional return values through projections.
-        Node* low_node = graph()->NewNode(common()->Projection(0), node);
-        Node* high_node = graph()->NewNode(common()->Projection(1), node);
+        Node* low_node =
+            graph()->NewNode(common()->Projection(0), node, graph()->start());
+        Node* high_node =
+            graph()->NewNode(common()->Projection(1), node, graph()->start());
         ReplaceNode(node, low_node, high_node);
       }
       break;
     }
     case IrOpcode::kWord64And: {
       DCHECK(node->InputCount() == 2);
       Node* left = node->InputAt(0);
       Node* right = node->InputAt(1);
 
       Node* low_node =
@@ skipping 18 matching lines @@
       Node* right = node->InputAt(1);
       node->ReplaceInput(1, GetReplacementLow(right));
       node->AppendInput(zone(), GetReplacementHigh(right));
 
       Node* left = node->InputAt(0);
       node->ReplaceInput(0, GetReplacementLow(left));
       node->InsertInput(zone(), 1, GetReplacementHigh(left));
 
       NodeProperties::ChangeOp(node, machine()->Int32PairAdd());
       // We access the additional return values through projections.
-      Node* low_node = graph()->NewNode(common()->Projection(0), node);
-      Node* high_node = graph()->NewNode(common()->Projection(1), node);
+      Node* low_node =
+          graph()->NewNode(common()->Projection(0), node, graph()->start());
+      Node* high_node =
+          graph()->NewNode(common()->Projection(1), node, graph()->start());
       ReplaceNode(node, low_node, high_node);
       break;
     }
     case IrOpcode::kInt64Sub: {
       DCHECK(node->InputCount() == 2);
 
       Node* right = node->InputAt(1);
       node->ReplaceInput(1, GetReplacementLow(right));
       node->AppendInput(zone(), GetReplacementHigh(right));
 
       Node* left = node->InputAt(0);
       node->ReplaceInput(0, GetReplacementLow(left));
       node->InsertInput(zone(), 1, GetReplacementHigh(left));
 
       NodeProperties::ChangeOp(node, machine()->Int32PairSub());
       // We access the additional return values through projections.
-      Node* low_node = graph()->NewNode(common()->Projection(0), node);
-      Node* high_node = graph()->NewNode(common()->Projection(1), node);
+      Node* low_node =
+          graph()->NewNode(common()->Projection(0), node, graph()->start());
+      Node* high_node =
+          graph()->NewNode(common()->Projection(1), node, graph()->start());
       ReplaceNode(node, low_node, high_node);
       break;
     }
     case IrOpcode::kInt64Mul: {
       DCHECK(node->InputCount() == 2);
 
       Node* right = node->InputAt(1);
       node->ReplaceInput(1, GetReplacementLow(right));
       node->AppendInput(zone(), GetReplacementHigh(right));
 
       Node* left = node->InputAt(0);
       node->ReplaceInput(0, GetReplacementLow(left));
       node->InsertInput(zone(), 1, GetReplacementHigh(left));
 
       NodeProperties::ChangeOp(node, machine()->Int32PairMul());
       // We access the additional return values through projections.
-      Node* low_node = graph()->NewNode(common()->Projection(0), node);
-      Node* high_node = graph()->NewNode(common()->Projection(1), node);
+      Node* low_node =
+          graph()->NewNode(common()->Projection(0), node, graph()->start());
+      Node* high_node =
+          graph()->NewNode(common()->Projection(1), node, graph()->start());
       ReplaceNode(node, low_node, high_node);
       break;
     }
     case IrOpcode::kWord64Or: {
       DCHECK(node->InputCount() == 2);
       Node* left = node->InputAt(0);
       Node* right = node->InputAt(1);
 
       Node* low_node =
           graph()->NewNode(machine()->Word32Or(), GetReplacementLow(left),
@@ skipping 28 matching lines @@
         // the shift can only be between 0 and 63 anyways.
         node->ReplaceInput(1, GetReplacementLow(shift));
       }
 
       Node* value = node->InputAt(0);
       node->ReplaceInput(0, GetReplacementLow(value));
       node->InsertInput(zone(), 1, GetReplacementHigh(value));
 
       NodeProperties::ChangeOp(node, machine()->Word32PairShl());
       // We access the additional return values through projections.
-      Node* low_node = graph()->NewNode(common()->Projection(0), node);
-      Node* high_node = graph()->NewNode(common()->Projection(1), node);
+      Node* low_node =
+          graph()->NewNode(common()->Projection(0), node, graph()->start());
+      Node* high_node =
+          graph()->NewNode(common()->Projection(1), node, graph()->start());
       ReplaceNode(node, low_node, high_node);
       break;
     }
     case IrOpcode::kWord64Shr: {
       // TODO(turbofan): if the shift count >= 32, then we can set the low word
       // of the output to 0 and just calculate the high word.
       DCHECK(node->InputCount() == 2);
       Node* shift = node->InputAt(1);
       if (HasReplacementLow(shift)) {
         // We do not have to care about the high word replacement, because
         // the shift can only be between 0 and 63 anyways.
         node->ReplaceInput(1, GetReplacementLow(shift));
       }
 
       Node* value = node->InputAt(0);
       node->ReplaceInput(0, GetReplacementLow(value));
       node->InsertInput(zone(), 1, GetReplacementHigh(value));
 
       NodeProperties::ChangeOp(node, machine()->Word32PairShr());
       // We access the additional return values through projections.
-      Node* low_node = graph()->NewNode(common()->Projection(0), node);
-      Node* high_node = graph()->NewNode(common()->Projection(1), node);
+      Node* low_node =
+          graph()->NewNode(common()->Projection(0), node, graph()->start());
+      Node* high_node =
+          graph()->NewNode(common()->Projection(1), node, graph()->start());
       ReplaceNode(node, low_node, high_node);
       break;
     }
     case IrOpcode::kWord64Sar: {
       // TODO(turbofan): if the shift count >= 32, then we can set the low word
       // of the output to 0 and just calculate the high word.
       DCHECK(node->InputCount() == 2);
       Node* shift = node->InputAt(1);
       if (HasReplacementLow(shift)) {
         // We do not have to care about the high word replacement, because
         // the shift can only be between 0 and 63 anyways.
         node->ReplaceInput(1, GetReplacementLow(shift));
       }
 
       Node* value = node->InputAt(0);
       node->ReplaceInput(0, GetReplacementLow(value));
       node->InsertInput(zone(), 1, GetReplacementHigh(value));
 
       NodeProperties::ChangeOp(node, machine()->Word32PairSar());
       // We access the additional return values through projections.
-      Node* low_node = graph()->NewNode(common()->Projection(0), node);
-      Node* high_node = graph()->NewNode(common()->Projection(1), node);
+      Node* low_node =
+          graph()->NewNode(common()->Projection(0), node, graph()->start());
+      Node* high_node =
+          graph()->NewNode(common()->Projection(1), node, graph()->start());
       ReplaceNode(node, low_node, high_node);
       break;
     }
     case IrOpcode::kWord64Equal: {
       DCHECK(node->InputCount() == 2);
       Node* left = node->InputAt(0);
       Node* right = node->InputAt(1);
 
       // TODO(wasm): Use explicit comparisons and && here?
       Node* replacement = graph()->NewNode(
@@ skipping 372 matching lines @@
                     common()->Phi(MachineRepresentation::kWord32, value_count),
                     value_count + 1, inputs_low, false),
                 graph()->NewNode(
                     common()->Phi(MachineRepresentation::kWord32, value_count),
                     value_count + 1, inputs_high, false));
   }
 }
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8