[turbofan] Introduce dedicated NumberToBoolean operator.

src/compiler/simplified-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/simplified-lowering.h"
 
 #include <limits>
 
 #include "src/address-map.h"
 #include "src/base/bits.h"
@@ skipping 1987 matching lines @@
           if (lower()) DeferReplacement(node, lowering->Float64Sign(node));
         }
         return;
       }
       case IrOpcode::kNumberSqrt: {
         VisitUnop(node, UseInfo::TruncatingFloat64(),
                   MachineRepresentation::kFloat64);
         if (lower()) NodeProperties::ChangeOp(node, Float64Op(node));
         return;
       }
+      case IrOpcode::kNumberToBoolean: {
+        Type* const input_type = TypeOf(node->InputAt(0));
+        if (input_type->Is(Type::Integral32())) {
+          VisitUnop(node, UseInfo::TruncatingWord32(),
+                    MachineRepresentation::kBit);
+          if (lower()) lowering->DoIntegral32ToBit(node);
+        } else if (input_type->Is(Type::OrderedNumber())) {
+          VisitUnop(node, UseInfo::TruncatingFloat64(),
+                    MachineRepresentation::kBit);
+          if (lower()) lowering->DoOrderedNumberToBit(node);
+        } else {
+          VisitUnop(node, UseInfo::TruncatingFloat64(),
+                    MachineRepresentation::kBit);
+          if (lower()) lowering->DoNumberToBit(node);
+        }
+        return;
+      }
       case IrOpcode::kNumberToInt32: {
         // Just change representation if necessary.
         VisitUnop(node, UseInfo::TruncatingWord32(),
                   MachineRepresentation::kWord32);
         if (lower()) DeferReplacement(node, node->InputAt(0));
         return;
       }
       case IrOpcode::kNumberToUint32: {
         // Just change representation if necessary.
         VisitUnop(node, UseInfo::TruncatingWord32(),
@@ skipping 1162 matching lines @@
   CallDescriptor::Flags flags = CallDescriptor::kNoFlags;
   CallDescriptor* desc = Linkage::GetStubCallDescriptor(
       isolate(), graph()->zone(), callable.descriptor(), 0, flags, properties);
   node->InsertInput(graph()->zone(), 0,
                     jsgraph()->HeapConstant(callable.code()));
   node->AppendInput(graph()->zone(), jsgraph()->NoContextConstant());
   node->AppendInput(graph()->zone(), graph()->start());
   NodeProperties::ChangeOp(node, common()->Call(desc));
 }
 
+void SimplifiedLowering::DoIntegral32ToBit(Node* node) {
+  Node* const input = node->InputAt(0);
+  Node* const zero = jsgraph()->Int32Constant(0);
+  Operator const* const op = machine()->Word32Equal();
+
+  node->ReplaceInput(0, graph()->NewNode(op, input, zero));
+  node->AppendInput(graph()->zone(), zero);
+  NodeProperties::ChangeOp(node, op);
+}
+
+void SimplifiedLowering::DoOrderedNumberToBit(Node* node) {
+  Node* const input = node->InputAt(0);
+
+  node->ReplaceInput(0, graph()->NewNode(machine()->Float64Equal(), input,
+                                         jsgraph()->Float64Constant(0.0)));
+  node->AppendInput(graph()->zone(), jsgraph()->Int32Constant(0));
+  NodeProperties::ChangeOp(node, machine()->Word32Equal());
+}
+
+void SimplifiedLowering::DoNumberToBit(Node* node) {
+  Node* const input = node->InputAt(0);
+
+  node->ReplaceInput(0, jsgraph()->Float64Constant(0.0));
+  node->AppendInput(graph()->zone(),
+                    graph()->NewNode(machine()->Float64Abs(), input));
+  NodeProperties::ChangeOp(node, machine()->Float64LessThan());
+}
+
 Node* SimplifiedLowering::ToNumberCode() {
   if (!to_number_code_.is_set()) {
     Callable callable = CodeFactory::ToNumber(isolate());
     to_number_code_.set(jsgraph()->HeapConstant(callable.code()));
   }
   return to_number_code_.get();
 }
 
 Operator const* SimplifiedLowering::ToNumberOperator() {
   if (!to_number_operator_.is_set()) {
     Callable callable = CodeFactory::ToNumber(isolate());
     CallDescriptor::Flags flags = CallDescriptor::kNeedsFrameState;
     CallDescriptor* desc = Linkage::GetStubCallDescriptor(
         isolate(), graph()->zone(), callable.descriptor(), 0, flags,
         Operator::kNoProperties);
     to_number_operator_.set(common()->Call(desc));
   }
   return to_number_operator_.get();
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8