1 files changed, 59 insertions, 28 deletions

diff --git a/deps/v8/src/compiler/machine-operator-reducer.cc b/deps/v8/src/compiler/machine-operator-reducer.cc
index 99044aa86d..0ad20f0684 100644
--- a/deps/v8/src/compiler/machine-operator-reducer.cc
+++ b/deps/v8/src/compiler/machine-operator-reducer.cc
@@ -150,21 +150,8 @@ Reduction MachineOperatorReducer::Reduce(Node* node) {
       return ReduceWord32And(node);
     case IrOpcode::kWord32Or:
       return ReduceWord32Or(node);
-    case IrOpcode::kWord32Xor: {
-      Int32BinopMatcher m(node);
-      if (m.right().Is(0)) return Replace(m.left().node());  // x ^ 0 => x
-      if (m.IsFoldable()) {                                  // K ^ K => K
-        return ReplaceInt32(m.left().Value() ^ m.right().Value());
-      }
-      if (m.LeftEqualsRight()) return ReplaceInt32(0);  // x ^ x => 0
-      if (m.left().IsWord32Xor() && m.right().Is(-1)) {
-        Int32BinopMatcher mleft(m.left().node());
-        if (mleft.right().Is(-1)) {  // (x ^ -1) ^ -1 => x
-          return Replace(mleft.left().node());
-        }
-      }
-      break;
-    }
+    case IrOpcode::kWord32Xor:
+      return ReduceWord32Xor(node);
     case IrOpcode::kWord32Shl:
       return ReduceWord32Shl(node);
     case IrOpcode::kWord64Shl:
@@ -418,6 +405,11 @@ Reduction MachineOperatorReducer::Reduce(Node* node) {
       if (m.IsFoldable()) {  // K * K => K
         return ReplaceFloat64(m.left().Value() * m.right().Value());
       }
+      if (m.right().Is(2)) {  // x * 2.0 => x + x
+        node->ReplaceInput(1, m.left().node());
+        NodeProperties::ChangeOp(node, machine()->Float64Add());
+        return Changed(node);
+      }
       break;
     }
     case IrOpcode::kFloat64Div: {
@@ -432,6 +424,19 @@ Reduction MachineOperatorReducer::Reduce(Node* node) {
       if (m.IsFoldable()) {  // K / K => K
         return ReplaceFloat64(m.left().Value() / m.right().Value());
       }
+      if (m.right().Is(-1)) {  // x / -1.0 => -x
+        node->RemoveInput(1);
+        NodeProperties::ChangeOp(node, machine()->Float64Neg());
+        return Changed(node);
+      }
+      if (m.right().IsNormal() && m.right().IsPositiveOrNegativePowerOf2()) {
+        // All reciprocals of non-denormal powers of two can be represented
+        // exactly, so division by power of two can be reduced to
+        // multiplication by reciprocal, with the same result.
+        node->ReplaceInput(1, Float64Constant(1.0 / m.right().Value()));
+        NodeProperties::ChangeOp(node, machine()->Float64Mul());
+        return Changed(node);
+      }
       break;
     }
     case IrOpcode::kFloat64Mod: {
@@ -541,8 +546,9 @@ Reduction MachineOperatorReducer::Reduce(Node* node) {
     }
     case IrOpcode::kFloat64Pow: {
       Float64BinopMatcher m(node);
-      // TODO(bmeurer): Constant fold once we have a unified pow implementation.
-      if (m.right().Is(0.0)) {  // x ** +-0.0 => 1.0
+      if (m.IsFoldable()) {
+        return ReplaceFloat64(Pow(m.left().Value(), m.right().Value()));
+      } else if (m.right().Is(0.0)) {  // x ** +-0.0 => 1.0
         return ReplaceFloat64(1.0);
       } else if (m.right().Is(-2.0)) {  // x ** -2.0 => 1 / (x * x)
         node->ReplaceInput(0, Float64Constant(1.0));
@@ -1221,22 +1227,17 @@ Reduction MachineOperatorReducer::ReduceWord32And(Node* node) {
   return NoChange();
 }
 
-
-Reduction MachineOperatorReducer::ReduceWord32Or(Node* node) {
-  DCHECK_EQ(IrOpcode::kWord32Or, node->opcode());
+Reduction MachineOperatorReducer::TryMatchWord32Ror(Node* node) {
+  DCHECK(IrOpcode::kWord32Or == node->opcode() ||
+         IrOpcode::kWord32Xor == node->opcode());
   Int32BinopMatcher m(node);
-  if (m.right().Is(0)) return Replace(m.left().node());    // x | 0  => x
-  if (m.right().Is(-1)) return Replace(m.right().node());  // x | -1 => -1
-  if (m.IsFoldable()) {                                    // K | K  => K
-    return ReplaceInt32(m.left().Value() | m.right().Value());
-  }
-  if (m.LeftEqualsRight()) return Replace(m.left().node());  // x | x => x
-
   Node* shl = nullptr;
   Node* shr = nullptr;
-  // Recognize rotation, we are matching either:
+  // Recognize rotation, we are matching:
   //  * x << y | x >>> (32 - y) => x ror (32 - y), i.e  x rol y
   //  * x << (32 - y) | x >>> y => x ror y
+  //  * x << y ^ x >>> (32 - y) => x ror (32 - y), i.e. x rol y
+  //  * x << (32 - y) ^ x >>> y => x ror y
   // as well as their commuted form.
   if (m.left().IsWord32Shl() && m.right().IsWord32Shr()) {
     shl = m.left().node();
@@ -1278,6 +1279,36 @@ Reduction MachineOperatorReducer::ReduceWord32Or(Node* node) {
   return Changed(node);
 }
 
+Reduction MachineOperatorReducer::ReduceWord32Or(Node* node) {
+  DCHECK_EQ(IrOpcode::kWord32Or, node->opcode());
+  Int32BinopMatcher m(node);
+  if (m.right().Is(0)) return Replace(m.left().node());    // x | 0  => x
+  if (m.right().Is(-1)) return Replace(m.right().node());  // x | -1 => -1
+  if (m.IsFoldable()) {                                    // K | K  => K
+    return ReplaceInt32(m.left().Value() | m.right().Value());
+  }
+  if (m.LeftEqualsRight()) return Replace(m.left().node());  // x | x => x
+
+  return TryMatchWord32Ror(node);
+}
+
+Reduction MachineOperatorReducer::ReduceWord32Xor(Node* node) {
+  DCHECK_EQ(IrOpcode::kWord32Xor, node->opcode());
+  Int32BinopMatcher m(node);
+  if (m.right().Is(0)) return Replace(m.left().node());  // x ^ 0 => x
+  if (m.IsFoldable()) {                                  // K ^ K => K
+    return ReplaceInt32(m.left().Value() ^ m.right().Value());
+  }
+  if (m.LeftEqualsRight()) return ReplaceInt32(0);  // x ^ x => 0
+  if (m.left().IsWord32Xor() && m.right().Is(-1)) {
+    Int32BinopMatcher mleft(m.left().node());
+    if (mleft.right().Is(-1)) {  // (x ^ -1) ^ -1 => x
+      return Replace(mleft.left().node());
+    }
+  }
+
+  return TryMatchWord32Ror(node);
+}
 
 Reduction MachineOperatorReducer::ReduceFloat64InsertLowWord32(Node* node) {
   DCHECK_EQ(IrOpcode::kFloat64InsertLowWord32, node->opcode());