[turbofan] Type feedback for numeric comparisons.

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 1020 matching lines @@
       }
     }
   }
 
   void ChangeToInt32OverflowOp(Node* node, const Operator* op) {
     Node* effect = NodeProperties::GetEffectInput(node);
     Node* control = NodeProperties::GetControlInput(node);
     Node* frame_state = NodeProperties::FindFrameStateBefore(node);
     Node* arith = graph()->NewNode(op, node->InputAt(0), node->InputAt(1));
     Node* overflow = graph()->NewNode(common()->Projection(1), arith);
-    control = effect = graph()->NewNode(common()->DeoptimizeIf(), overflow,
-                                        frame_state, effect, control);
 
+    // Deoptimize on overflow.

[Benedikt Meurer, 2016/06/07 04:11:00]

This change doesn't seem related to comparisons?

[Jarin, 2016/06/09 13:37:32]

Done.

+    Node* branch = graph()->NewNode(common()->Branch(BranchHint::kFalse),
+                                    overflow, control);
+    Node* if_true = graph()->NewNode(common()->IfTrue(), branch);
+    Node* deoptimize =
+        graph()->NewNode(common()->Deoptimize(DeoptimizeKind::kEager),
+                         frame_state, effect, if_true);
+    NodeProperties::MergeControlToEnd(graph(), common(), deoptimize);
+
+    control = graph()->NewNode(common()->IfFalse(), branch);
     Node* value = graph()->NewNode(common()->Projection(0), arith);
     ReplaceEffectControlUses(node, effect, control);
     DeferReplacement(node, value);
   }
 
   void VisitSpeculativeAdditiveOp(Node* node, Truncation truncation,
                                   SimplifiedLowering* lowering) {
     if (BothInputsAre(node, Type::Signed32()) &&
         NodeProperties::GetType(node)->Is(Type::Signed32())) {
       // int32 + int32 = int32   ==>   signed Int32Add/Sub
@@ skipping 158 matching lines @@
           // No input representation requirement; adapt during lowering.
           ProcessInput(node, 0, UseInfo::AnyTruncatingToBool());
           SetOutput(node, MachineRepresentation::kWord32);
         }
         return;
       }
       case IrOpcode::kNumberEqual:
       case IrOpcode::kNumberLessThan:
       case IrOpcode::kNumberLessThanOrEqual: {
         // Number comparisons reduce to integer comparisons for integer inputs.
-        if (BothInputsAreSigned32(node)) {
+        if (TypeOf(node->InputAt(0))->Is(Type::Signed32()) &&
+            TypeOf(node->InputAt(1))->Is(Type::Signed32())) {
           // => signed Int32Cmp
           VisitInt32Cmp(node);
           if (lower()) NodeProperties::ChangeOp(node, Int32Op(node));
-        } else if (BothInputsAreUnsigned32(node)) {
+        } else if (TypeOf(node->InputAt(0))->Is(Type::Unsigned32()) &&
+                   TypeOf(node->InputAt(1))->Is(Type::Unsigned32())) {
           // => unsigned Int32Cmp
           VisitUint32Cmp(node);
           if (lower()) NodeProperties::ChangeOp(node, Uint32Op(node));
         } else {
           // => Float64Cmp
           VisitFloat64Cmp(node);
           if (lower()) NodeProperties::ChangeOp(node, Float64Op(node));
         }
         return;
       }
 
       case IrOpcode::kSpeculativeNumberAdd:
       case IrOpcode::kSpeculativeNumberSubtract:
         return VisitSpeculativeAdditiveOp(node, truncation, lowering);
 
+      case IrOpcode::kSpeculativeNumberLessThan:
+      case IrOpcode::kSpeculativeNumberLessThanOrEqual:
+      case IrOpcode::kSpeculativeNumberEqual: {
+        // Number comparisons reduce to integer comparisons for integer inputs.
+        if (TypeOf(node->InputAt(0))->Is(Type::Signed32()) &&
+            TypeOf(node->InputAt(1))->Is(Type::Signed32())) {
+          // => signed Int32Cmp
+          VisitInt32Cmp(node);
+          if (lower()) ChangeToPureOp(node, Int32Op(node));
+          return;
+        } else if (TypeOf(node->InputAt(0))->Is(Type::Unsigned32()) &&
+                   TypeOf(node->InputAt(1))->Is(Type::Unsigned32())) {
+          // => unsigned Int32Cmp
+          VisitUint32Cmp(node);
+          if (lower()) ChangeToPureOp(node, Uint32Op(node));
+          return;
+        }
+        // Try to use type feedback.
+        CompareOperationHints::Hint hint = CompareOperationHintOf(node->op());
+
+        if (hint == CompareOperationHints::kSignedSmall ||
+            hint == CompareOperationHints::kSigned32) {
+          VisitBinop(node, UseInfo::CheckedSigned32AsWord32(),
+                     MachineRepresentation::kBit);
+          if (lower()) ChangeToPureOp(node, Int32Op(node));
+          return;
+        }
+        DCHECK_EQ(CompareOperationHints::kNumberOrUndefined, hint);
+        // default case => Float64 comparison
+        VisitBinop(node, UseInfo::CheckedNumberOrUndefinedAsFloat64(),
+                   MachineRepresentation::kBit);
+        if (lower()) ChangeToPureOp(node, Float64Op(node));
+        return;
+      }
+
       case IrOpcode::kNumberAdd:
       case IrOpcode::kNumberSubtract: {
         if (BothInputsAre(node, Type::Signed32()) &&
             NodeProperties::GetType(node)->Is(Type::Signed32())) {
           // int32 + int32 = int32
           // => signed Int32Add/Sub
           VisitInt32Binop(node);
           if (lower()) NodeProperties::ChangeOp(node, Int32Op(node));
         } else if (BothInputsAre(node, type_cache_.kAdditiveSafeInteger) &&
                    truncation.TruncatesToWord32()) {
@@ skipping 1568 matching lines @@
         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