Introduce simplified BooleanToNumber operator.

test/cctest/compiler/test-simplified-lowering.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 <limits>
 
 #include "src/compiler/access-builder.h"
 #include "src/compiler/control-builders.h"
 #include "src/compiler/generic-node-inl.h"
 #include "src/compiler/graph-visualizer.h"
@@ skipping 792 matching lines @@
   t.Lower();
   CHECK_EQ(IrOpcode::kChangeBitToBool, use->InputAt(0)->opcode());
   Node* cmp = use->InputAt(0)->InputAt(0);
   CHECK_EQ(t.machine()->WordEqual()->opcode(), cmp->opcode());
   CHECK(b == cmp->InputAt(0) || b == cmp->InputAt(1));
   Node* f = t.jsgraph.FalseConstant();
   CHECK(f == cmp->InputAt(0) || f == cmp->InputAt(1));
 }
 
 
+TEST(LowerBooleanToNumber_bit_int32) {
+  // BooleanToNumber(x: kRepBit) used as kMachInt32
+  TestingGraph t(Type::Boolean());
+  Node* b = t.ExampleWithOutput(kRepBit);
+  Node* cnv = t.graph()->NewNode(t.simplified()->BooleanToNumber(), b);
+  Node* use = t.Use(cnv, kMachInt32);
+  t.Return(use);
+  t.Lower();
+  CHECK_EQ(b, use->InputAt(0));
+}
+
+
+TEST(LowerBooleanToNumber_tagged_int32) {

[titzer, 2014/09/17 12:01:22]

Maybe also want to test it being used as tagged, to make sure that you don't get
the boolean, but a tagged number result.

[Michael Starzinger, 2014/09/17 12:43:28]

Done (both kRepBit and kRepTagged used as tagged).

+  // BooleanToNumber(x: kRepTagged) used as kMachInt32
+  TestingGraph t(Type::Boolean());
+  Node* b = t.p0;
+  Node* cnv = t.graph()->NewNode(t.simplified()->BooleanToNumber(), b);
+  Node* use = t.Use(cnv, kMachInt32);
+  t.Return(use);
+  t.Lower();
+  CHECK_EQ(t.machine()->WordEqual()->opcode(), cnv->opcode());
+  CHECK(b == cnv->InputAt(0) || b == cnv->InputAt(1));
+  Node* c = t.jsgraph.TrueConstant();
+  CHECK(c == cnv->InputAt(0) || c == cnv->InputAt(1));
+}
+
+
 static Type* test_types[] = {Type::Signed32(), Type::Unsigned32(),
                              Type::Number(), Type::Any()};
 
 
 TEST(LowerNumberCmp_to_int32) {
   TestingGraph t(Type::Signed32(), Type::Signed32());
 
   t.CheckLoweringBinop(IrOpcode::kWord32Equal, t.simplified()->NumberEqual());
   t.CheckLoweringBinop(IrOpcode::kInt32LessThan,
                        t.simplified()->NumberLessThan());
@@ skipping 623 matching lines @@
     Node* phi = t.graph()->NewNode(t.common()->Phi(kMachAnyTagged, 2), load0,
                                    load1, t.start);
     t.Return(t.Use(phi, kMachineTypes[i]));
     t.Lower();
 
     CHECK_EQ(IrOpcode::kPhi, phi->opcode());
     CHECK_EQ(RepresentationOf(kMachineTypes[i]),
              RepresentationOf(OpParameter<MachineType>(phi)));
   }
 }