[turbofan] Unify Math.floor / Math.ceil optimization.

src/compiler/arm64/instruction-selector-arm64.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/instruction-selector-impl.h"
 #include "src/compiler/node-matchers.h"
 #include "src/compiler/node-properties.h"
 
 namespace v8 {
 namespace internal {
@@ skipping 1015 matching lines @@
   Emit(kArm64Mov32, g.DefineAsRegister(node), g.UseRegister(node->InputAt(0)));
 }
 
 
 void InstructionSelector::VisitFloat64Add(Node* node) {
   VisitRRRFloat64(this, kArm64Float64Add, node);
 }
 
 
 void InstructionSelector::VisitFloat64Sub(Node* node) {
+  Arm64OperandGenerator g(this);
+  Float64BinopMatcher m(node);
+  if (m.left().IsMinusZero() && m.right().IsFloat64RoundDown() &&
+      CanCover(m.node(), m.right().node())) {
+    if (m.right().InputAt(0)->opcode() == IrOpcode::kFloat64Sub &&
+        CanCover(m.right().node(), m.right().InputAt(0))) {
+      Float64BinopMatcher mright0(m.right().InputAt(0));
+      if (mright0.left().IsMinusZero()) {
+        Emit(kArm64Float64RoundUp, g.DefineAsRegister(node),
+             g.UseRegister(mright0.right().node()));
+        return;
+      }
+    }
+  }
   VisitRRRFloat64(this, kArm64Float64Sub, node);
 }
 
 
 void InstructionSelector::VisitFloat64Mul(Node* node) {
   VisitRRRFloat64(this, kArm64Float64Mul, node);
 }
 
 
 void InstructionSelector::VisitFloat64Div(Node* node) {
   VisitRRRFloat64(this, kArm64Float64Div, node);
 }
 
 
 void InstructionSelector::VisitFloat64Mod(Node* node) {
   Arm64OperandGenerator g(this);
   Emit(kArm64Float64Mod, g.DefineAsFixed(node, d0),
        g.UseFixed(node->InputAt(0), d0),
        g.UseFixed(node->InputAt(1), d1))->MarkAsCall();
 }
 
 
 void InstructionSelector::VisitFloat64Sqrt(Node* node) {
   VisitRRFloat64(this, kArm64Float64Sqrt, node);
 }
 
 
-void InstructionSelector::VisitFloat64Floor(Node* node) {
-  VisitRRFloat64(this, kArm64Float64Floor, node);
+void InstructionSelector::VisitFloat64RoundDown(Node* node) {
+  VisitRRFloat64(this, kArm64Float64RoundDown, node);
 }
 
 
-void InstructionSelector::VisitFloat64Ceil(Node* node) {
-  VisitRRFloat64(this, kArm64Float64Ceil, node);
-}
-
-
 void InstructionSelector::VisitFloat64RoundTruncate(Node* node) {
   VisitRRFloat64(this, kArm64Float64RoundTruncate, node);
 }
 
 
 void InstructionSelector::VisitFloat64RoundTiesAway(Node* node) {
   VisitRRFloat64(this, kArm64Float64RoundTiesAway, node);
 }
 
 
@@ skipping 523 matching lines @@
   Node* left = node->InputAt(0);
   Node* right = node->InputAt(1);
   Emit(kArm64Float64InsertHighWord32, g.DefineAsRegister(node),
        g.UseRegister(left), g.UseRegister(right));
 }
 
 
 // static
 MachineOperatorBuilder::Flags
 InstructionSelector::SupportedMachineOperatorFlags() {
-  return MachineOperatorBuilder::kFloat64Floor |
-         MachineOperatorBuilder::kFloat64Ceil |
+  return MachineOperatorBuilder::kFloat64RoundDown |
          MachineOperatorBuilder::kFloat64RoundTruncate |
          MachineOperatorBuilder::kFloat64RoundTiesAway |
          MachineOperatorBuilder::kWord32ShiftIsSafe |
          MachineOperatorBuilder::kInt32DivIsSafe |
          MachineOperatorBuilder::kUint32DivIsSafe;
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8