Add a new class InvokeDynamicSpecializer and subclasses that know what input types are beneficial f…

sdk/lib/_internal/compiler/implementation/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
+ * dynamic to a builtin instruction (e.g. HIndex, HBitNot).
+ */
+class InvokeDynamicSpecializer {
+  const InvokeDynamicSpecializer();
+
+  HType computeDesiredTypeForInput(HInvokeDynamicMethod instruction,
+                                   HInstruction input,
+                                   HTypeMap types,
+                                   Compiler compiler) {
+    return HType.UNKNOWN;
+  }
+
+  HType computeTypeFromInputTypes(HInvokeDynamicMethod instruction,
+                                  HTypeMap types,
+                                  Compiler compiler) {
+    return HType.UNKNOWN;
+  }
+
+  HInstruction tryConvertToBuiltin(HInvokeDynamicMethod instruction,
+                                   HTypeMap types) {
+    return null;
+  }
+
+  static InvokeDynamicSpecializer lookupSpecializer(Selector selector) {
+    if (selector.kind == SelectorKind.INDEX) {
+      return selector.name == const SourceString('[]')
+          ? const IndexSpecializer()
+          : const IndexAssignSpecializer();
+    } else if (selector.kind == SelectorKind.OPERATOR) {
+      if (selector.name == const SourceString('unary-')) {
+        return const UnaryNegateSpecializer();
+      } else if (selector.name == const SourceString('~')) {
+        return const BitNotSpecializer();
+      }
+    }
+    return const InvokeDynamicSpecializer();
+  }
+}
+
+class IndexAssignSpecializer extends InvokeDynamicSpecializer {
+  const IndexAssignSpecializer();
+
+  HType computeDesiredTypeForInput(HInvokeDynamicMethod instruction,
+                                   HInstruction input,
+                                   HTypeMap types,
+                                   Compiler compiler) {
+    HInstruction index = instruction.inputs[2];
+    if (input == instruction.inputs[1] &&
+        (index.isTypeUnknown(types) || index.isNumber(types))) {
+      return HType.MUTABLE_ARRAY;
+    }
+    // The index should be an int when the receiver is a string or array.
+    // However it turns out that inserting an integer check in the optimized
+    // version is cheaper than having another bailout case. This is true,
+    // because the integer check will simply throw if it fails.
+    return HType.UNKNOWN;
+  }
+
+  HInstruction tryConvertToBuiltin(HInvokeDynamicMethod instruction,
+                                   HTypeMap types) {
+    if (instruction.inputs[1].isMutableArray(types)) {
+      return new HIndexAssign(instruction.inputs[1],
+                              instruction.inputs[2],
+                              instruction.inputs[3]);
+    }
+    return null;
+  }
+}
+
+class IndexSpecializer extends InvokeDynamicSpecializer {
+  const IndexSpecializer();
+
+  HType computeDesiredTypeForInput(HInvokeDynamicMethod instruction,
+                                   HInstruction input,
+                                   HTypeMap types,
+                                   Compiler compiler) {
+    HInstruction index = instruction.inputs[2];
+    if (input == instruction.inputs[1] &&
+        (index.isTypeUnknown(types) || index.isNumber(types))) {
+      return HType.INDEXABLE_PRIMITIVE;
+    }
+    // The index should be an int when the receiver is a string or array.
+    // However it turns out that inserting an integer check in the optimized
+    // version is cheaper than having another bailout case. This is true,
+    // because the integer check will simply throw if it fails.
+    return HType.UNKNOWN;
+  }
+
+  HInstruction tryConvertToBuiltin(HInvokeDynamicMethod instruction,
+                                   HTypeMap types) {
+    if (instruction.inputs[1].isIndexablePrimitive(types)) {
+      return new HIndex(instruction.inputs[1], instruction.inputs[2]);
+    }
+    return null;
+  }
+}
+
+class BitNotSpecializer extends InvokeDynamicSpecializer {
+  const BitNotSpecializer();
+
+  HType computeDesiredTypeForInput(HInvokeDynamicMethod instruction,
+                                   HInstruction input,
+                                   HTypeMap types,
+                                   Compiler compiler) {
+    if (input == instruction.inputs[1]) {
+      HType propagatedType = types[instruction];
+      if (propagatedType.isUnknown() || propagatedType.isNumber()) {
+        return HType.INTEGER;
+      }
+    }
+    return HType.UNKNOWN;
+  }
+
+  HType computeTypeFromInputTypes(HInvokeDynamicMethod instruction,
+                                  HTypeMap types,
+                                  Compiler compiler) {
+    // All bitwise operations on primitive types either produce an
+    // integer or throw an error.
+    if (instruction.inputs[1].isPrimitive(types)) return HType.INTEGER;
+    return HType.UNKNOWN;
+  }
+
+  HInstruction tryConvertToBuiltin(HInvokeDynamicMethod instruction,
+                                   HTypeMap types) {
+    HInstruction input = instruction.inputs[1];
+    if (input.isNumber(types)) return new HBitNot(input);
+    return null;
+  }
+}
+
+class UnaryNegateSpecializer extends InvokeDynamicSpecializer {
+  const UnaryNegateSpecializer();
+
+  HType computeDesiredTypeForInput(HInvokeDynamicMethod instruction,
+                                   HInstruction input,
+                                   HTypeMap types,
+                                   Compiler compiler) {
+    if (input == instruction.inputs[1]) {
+      HType propagatedType = types[instruction];
+      // If the outgoing type should be a number (integer, double or both) we
+      // want the outgoing type to be the input too.
+      // If we don't know the outgoing type we try to make it a number.
+      if (propagatedType.isNumber()) return propagatedType;
+      if (propagatedType.isUnknown()) return HType.NUMBER;
+    }
+    return HType.UNKNOWN;
+  }
+
+  HType computeTypeFromInputTypes(HInvokeDynamicMethod instruction,
+                                  HTypeMap types,
+                                  Compiler compiler) {
+    HType operandType = types[instruction.inputs[1]];
+    if (operandType.isNumber()) return operandType;
+    return HType.UNKNOWN;
+  }
+
+  HInstruction tryConvertToBuiltin(HInvokeDynamicMethod instruction,
+                                   HTypeMap types) {
+    HInstruction input = instruction.inputs[1];
+    if (input.isNumber(types)) return new HNegate(input);
+    return null;
+  }
+}