[turbofan] Add TruncateFloat32ToUint32 operator to Turbofan.

test/cctest/compiler/test-run-machops.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 <cmath>
 #include <functional>
 #include <limits>
 
 #include "src/base/bits.h"
 #include "src/base/utils/random-number-generator.h"
@@ skipping 4118 matching lines @@
   m.Return(m.TruncateFloat32ToInt32(m.Parameter(0)));
   FOR_FLOAT32_INPUTS(i) {
     if (*i <= static_cast<float>(std::numeric_limits<int32_t>::max()) &&
         *i >= static_cast<float>(std::numeric_limits<int32_t>::min())) {
       CheckFloatEq(static_cast<int32_t>(*i), m.Call(*i));
     }
   }
 }
 
 
+TEST(RunTruncateFloat32ToUint32) {
+  BufferedRawMachineAssemblerTester<uint32_t> m(MachineType::Float32());
+  m.Return(m.TruncateFloat32ToUint32(m.Parameter(0)));
+
+  FOR_UINT32_INPUTS(i) {

[ahaas, 2016/01/29 10:45:08]

Could you also run tests for FOR_FLOAT32_INPUTS where the value is within
uint32_t range?

+    float input = static_cast<float>(*i);
+    // This condition on 'input' is required because
+    // static_cast<float>(UINT32_MAX) results in a value outside uint32 range.
+    if (input < static_cast<float>(UINT32_MAX)) {
+      CHECK_EQ(static_cast<uint32_t>(input), m.Call(input));
+    }
+  }
+}
+
+
 TEST(RunChangeFloat64ToInt32_A) {
   BufferedRawMachineAssemblerTester<int32_t> m;
   double magic = 11.1;
   m.Return(m.ChangeFloat64ToInt32(m.Float64Constant(magic)));
   CHECK_EQ(static_cast<int32_t>(magic), m.Call());
 }
 
 
 TEST(RunChangeFloat64ToInt32_B) {
   BufferedRawMachineAssemblerTester<int32_t> m(MachineType::Float64());
@@ skipping 1934 matching lines @@
   Node* call = r.AddNode(r.common()->Call(desc), phi);
   r.Return(call);
 
   CHECK_EQ(33, r.Call(1));
   CHECK_EQ(44, r.Call(0));
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8