Implement SmiToInt and DoubleToInt.

runtime/vm/flow_graph_optimizer.cc

 // Copyright (c) 2012, 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.
 
 #include "vm/flow_graph_optimizer.h"
 
 #include "vm/bit_vector.h"
 #include "vm/cha.h"
 #include "vm/flow_graph_builder.h"
 #include "vm/flow_graph_compiler.h"
@@ skipping 869 matching lines @@
 
   return false;
 }
 
 
 // Inline only simple, frequently called core library methods.
 bool FlowGraphOptimizer::TryInlineInstanceMethod(InstanceCallInstr* call) {
   ASSERT(call->HasICData());
   const ICData& ic_data = *call->ic_data();
   if ((ic_data.NumberOfChecks() == 0) || !ic_data.HasOneTarget()) {
-    // No type feedback collected.
+    // No type feedback collected or multiple targets found.
     return false;
   }
   Function& target = Function::Handle();
   GrowableArray<intptr_t> class_ids;
   ic_data.GetCheckAt(0, &class_ids, &target);
   MethodRecognizer::Kind recognized_kind =
       MethodRecognizer::RecognizeKind(target);
 
   if ((recognized_kind == MethodRecognizer::kDoubleToDouble) &&
       (class_ids[0] == kDoubleCid)) {
     DoubleToDoubleInstr* d2d_instr =
         new DoubleToDoubleInstr(call->ArgumentAt(0)->value(), call);
     call->ReplaceWith(d2d_instr, current_iterator());
     RemovePushArguments(call);
     return true;
   }
 
   if ((recognized_kind == MethodRecognizer::kIntegerToDouble) &&
       (class_ids[0] == kSmiCid)) {
     SmiToDoubleInstr* s2d_instr = new SmiToDoubleInstr(call);
     call->ReplaceWith(s2d_instr, current_iterator());
     // Pushed arguments are not removed because SmiToDouble is implemented
     // as a call.
     return true;
   }
 
+  if ((recognized_kind == MethodRecognizer::kIntegerToInteger) &&
+      (class_ids[0] == kSmiCid)) {
+    // TODO(srdjan): implement also for BigInt and Mint.
+    InsertBefore(call,
+                 new CheckSmiInstr(call->ArgumentAt(0)->value()->Copy(),
+                                   call->deopt_id()),
+                 call->env(),
+                 Definition::kEffect);
+    IntegerToIntegerInstr* int2int_instr =
+        new IntegerToIntegerInstr(call->ArgumentAt(0)->value(), call, kSmiCid);
+    call->ReplaceWith(int2int_instr, current_iterator());

[Florian Schneider, 2012/10/09 11:13:58]

Since IntegerToInteger itself is a nop, I think you can avoid having an extra IL
instruction for Integer.toInt. Just do a CheckSmi/ClassCheck and then replace
all uses of the call with the input:

call->ReplaceUsesWith(call->ArgumentAt(0)->value());

[srdjan, 2012/10/09 21:23:04]

Done.

+    RemovePushArguments(call);
+    return true;
+  }
+
+  if ((recognized_kind == MethodRecognizer::kDoubleToInteger) &&
+      (class_ids[0] == kDoubleCid)) {
+    AddCheckClass(call, call->ArgumentAt(0)->value()->Copy());
+    DoubleToIntegerInstr* d2int_instr = new DoubleToIntegerInstr(call);
+    call->ReplaceWith(d2int_instr, current_iterator());
+    // Pushed arguments are not removed because DoubleToInt is implemented
+    // as a call.
+    return true;
+  }
+
   if (recognized_kind == MethodRecognizer::kStringBaseIsEmpty) {
     if (!ic_data.HasOneTarget()) {
       // Target is not only StringBase_get_length.
       return false;
     }
     InlineStringIsEmptyTester(call);
     return true;
   }
 
   return false;
 }
 
 
+// Tries to optimize instance call by replacing it with a faster instruction
+// (e.g, binary op, field load, ..).
 void FlowGraphOptimizer::VisitInstanceCall(InstanceCallInstr* instr) {
   if (instr->HasICData() && (instr->ic_data()->NumberOfChecks() > 0)) {
     const Token::Kind op_kind = instr->token_kind();
     if (Token::IsIndexOperator(op_kind) &&
         TryReplaceWithArrayOp(instr, op_kind)) {
       return;
     }
     if (Token::IsBinaryToken(op_kind) &&
         TryReplaceWithBinaryOp(instr, op_kind)) {
       return;
@@ skipping 2102 matching lines @@
   }
 }
 
 
 void ConstantPropagator::VisitSmiToDouble(SmiToDoubleInstr* instr) {
   // TODO(kmillikin): Handle conversion.
   SetValue(instr, non_constant_);
 }
 
 
+void ConstantPropagator::VisitIntegerToInteger(IntegerToIntegerInstr* instr) {
+  const Object& value = instr->value()->definition()->constant_value();
+  if (IsNonConstant(value)) {
+    SetValue(instr, non_constant_);
+  } else if (IsConstant(value)) {
+    // TODO(kmillikin): Handle conversion.
+    SetValue(instr, non_constant_);
+  }
+}
+
+
+void ConstantPropagator::VisitDoubleToInteger(DoubleToIntegerInstr* instr) {
+  // TODO(kmillikin): Handle conversion.
+  SetValue(instr, non_constant_);
+}
+
+
 void ConstantPropagator::VisitConstant(ConstantInstr* instr) {
   SetValue(instr, instr->value());
 }
 
 
 void ConstantPropagator::VisitConstraint(ConstraintInstr* instr) {
   // Should not be used outside of range analysis.
   UNREACHABLE();
 }
 
@@ skipping 195 matching lines @@
 
   if (FLAG_trace_constant_propagation) {
     OS::Print("\n==== After constant propagation ====\n");
     FlowGraphPrinter printer(*graph_);
     printer.PrintBlocks();
   }
 }
 
 
 }  // namespace dart