Optimize DateTime properties

pkg/compiler/lib/src/ssa/invoke_dynamic_specializers.dart

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of ssa;
 
 /**
  * [InvokeDynamicSpecializer] and its subclasses are helpers to
  * optimize intercepted dynamic calls. It knows what input types
  * would be beneficial for performance, and how to change a invoke
@@ skipping 205 matching lines @@
 
   void clearAllSideEffects(HInstruction instruction) {
     instruction.sideEffects.clearAllSideEffects();
     instruction.sideEffects.clearAllDependencies();
     instruction.setUseGvn();
   }
 
   bool inputsArePositiveIntegers(HInstruction instruction, Compiler compiler) {
     HInstruction left = instruction.inputs[1];
     HInstruction right = instruction.inputs[2];
-    JavaScriptBackend backend = compiler.backend;
     return left.isPositiveIntegerOrNull(compiler)
         && right.isPositiveIntegerOrNull(compiler);
   }
 
+  bool inputsAreUInt31(HInstruction instruction, Compiler compiler) {
+    HInstruction left = instruction.inputs[1];
+    HInstruction right = instruction.inputs[2];
+    return left.isUInt31(compiler) && right.isUInt31(compiler);
+  }
+
   HInstruction newBuiltinVariant(HInvokeDynamic instruction, Compiler compiler);
 
   Selector renameToOptimizedSelector(String name,
                                      Selector selector,
                                      Compiler compiler) {
     if (selector.name == name) return selector;
     JavaScriptBackend backend = compiler.backend;
     Selector newSelector = new Selector(
         SelectorKind.CALL, new Name(name, backend.interceptorsLibrary),
         new CallStructure(selector.argumentCount));
     return selector.mask == null
         ? newSelector
         : new TypedSelector(selector.mask, newSelector, compiler.world);
   }
 }
 
 class AddSpecializer extends BinaryArithmeticSpecializer {
   const AddSpecializer();
 
   TypeMask computeTypeFromInputTypes(HInvokeDynamic instruction,
                                      Compiler compiler) {
+    if (inputsAreUInt31(instruction, compiler)) {
+      JavaScriptBackend backend = compiler.backend;
+      return backend.uint32Type;
+    }
     if (inputsArePositiveIntegers(instruction, compiler)) {
       JavaScriptBackend backend = compiler.backend;
       return backend.positiveIntType;
     }
     return super.computeTypeFromInputTypes(instruction, compiler);
   }
 
   BinaryOperation operation(ConstantSystem constantSystem) {
     return constantSystem.add;
   }
@@ skipping 44 matching lines @@
     return super.computeTypeFromInputTypes(instruction, compiler);
   }
 
   BinaryOperation operation(ConstantSystem constantSystem) {
     return constantSystem.modulo;
   }
 
   HInstruction newBuiltinVariant(HInvokeDynamic instruction,
                                  Compiler compiler) {
     // Modulo cannot be mapped to the native operator (different semantics).
+    // TODO(sra): For non-negative values we can use JavaScript's %.
     return null;
   }
 }
 
 class MultiplySpecializer extends BinaryArithmeticSpecializer {
   const MultiplySpecializer();
 
   BinaryOperation operation(ConstantSystem constantSystem) {
     return constantSystem.multiply;
   }
@@ skipping 32 matching lines @@
 
 class TruncatingDivideSpecializer extends BinaryArithmeticSpecializer {
   const TruncatingDivideSpecializer();
 
   BinaryOperation operation(ConstantSystem constantSystem) {
     return constantSystem.truncatingDivide;
   }
 
   TypeMask computeTypeFromInputTypes(HInvokeDynamic instruction,
                                      Compiler compiler) {
+    JavaScriptBackend backend = compiler.backend;
+    if (hasUint31Result(instruction, compiler)) {
+      return backend.uint31Type;
+    }
     if (inputsArePositiveIntegers(instruction, compiler)) {
-      JavaScriptBackend backend = compiler.backend;
       return backend.positiveIntType;
     }
     return super.computeTypeFromInputTypes(instruction, compiler);
   }
 
   bool isNotZero(HInstruction instruction, Compiler compiler) {
     if (!instruction.isConstantInteger()) return false;
     HConstant rightConstant = instruction;
     IntConstantValue intConstant = rightConstant.constant;
     int count = intConstant.primitiveValue;
     return count != 0;
   }
 
+  bool isTwoOrGreater(HInstruction instruction, Compiler compiler) {
+    if (!instruction.isConstantInteger()) return false;
+    HConstant rightConstant = instruction;
+    IntConstantValue intConstant = rightConstant.constant;
+    int count = intConstant.primitiveValue;
+    return count >= 2;
+  }
+
+  bool hasUint31Result(HInstruction instruction, Compiler compiler) {
+    HInstruction left = instruction.inputs[1];
+    HInstruction right = instruction.inputs[2];
+    if (right.isPositiveInteger(compiler)) {
+      if (left.isUInt31(compiler) && isNotZero(right, compiler)) {
+        return true;
+      }
+      if (left.isUInt32(compiler) && isTwoOrGreater(right, compiler)) {
+        return true;
+      }
+    }
+    return false;
+  }
+
   HInstruction tryConvertToBuiltin(HInvokeDynamic instruction,
                                    Compiler compiler) {
     HInstruction left = instruction.inputs[1];
     HInstruction right = instruction.inputs[2];
     if (isBuiltin(instruction, compiler)) {
       if (right.isPositiveInteger(compiler) && isNotZero(right, compiler)) {
-        if (left.isUInt31(compiler)) {
+        if (hasUint31Result(instruction, compiler)) {
           return newBuiltinVariant(instruction, compiler);
         }
         // We can call _tdivFast because the rhs is a 32bit integer
         // and not 0, nor -1.
         instruction.selector = renameToOptimizedSelector(
             '_tdivFast', instruction.selector, compiler);
       }
       clearAllSideEffects(instruction);
     }
     return null;
@@ skipping 341 matching lines @@
     return constantSystem.codeUnitAt;
   }
 
   HInstruction tryConvertToBuiltin(HInvokeDynamic instruction,
                                    Compiler compiler) {
     // TODO(sra): Implement a builtin HCodeUnitAt instruction and the same index
     // bounds checking optimizations as for HIndex.
     return null;
   }
 }