[builtins] Introduce proper Float64Log1p operator.

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/ieee754.h"
@@ skipping 5493 matching lines @@
   CHECK(std::isnan(m.Call(-std::numeric_limits<double>::infinity())));
   CHECK(std::isnan(m.Call(-1.0)));
   CHECK_DOUBLE_EQ(-std::numeric_limits<double>::infinity(), m.Call(-0.0));
   CHECK_DOUBLE_EQ(-std::numeric_limits<double>::infinity(), m.Call(0.0));
   CHECK_DOUBLE_EQ(0.0, m.Call(1.0));
   CHECK_DOUBLE_EQ(std::numeric_limits<double>::infinity(),
                   m.Call(std::numeric_limits<double>::infinity()));
   FOR_FLOAT64_INPUTS(i) { CHECK_DOUBLE_EQ(ieee754::log(*i), m.Call(*i)); }
 }
 
+TEST(RunFloat64Log1p) {
+  BufferedRawMachineAssemblerTester<double> m(MachineType::Float64());
+  m.Return(m.Float64Log1p(m.Parameter(0)));
+  CHECK(std::isnan(m.Call(std::numeric_limits<double>::quiet_NaN())));
+  CHECK(std::isnan(m.Call(std::numeric_limits<double>::signaling_NaN())));
+  CHECK(std::isnan(m.Call(-std::numeric_limits<double>::infinity())));
+  CHECK_DOUBLE_EQ(-std::numeric_limits<double>::infinity(), m.Call(-1.0));
+  CHECK_DOUBLE_EQ(0.0, m.Call(0.0));
+  CHECK_DOUBLE_EQ(-0.0, m.Call(-0.0));
+  CHECK_DOUBLE_EQ(std::numeric_limits<double>::infinity(),
+                  m.Call(std::numeric_limits<double>::infinity()));
+  FOR_FLOAT64_INPUTS(i) { CHECK_DOUBLE_EQ(ieee754::log1p(*i), m.Call(*i)); }
+}
+
 static double two_30 = 1 << 30;             // 2^30 is a smi boundary.
 static double two_52 = two_30 * (1 << 22);  // 2^52 is a precision boundary.
 static double kValues[] = {0.1,
                            0.2,
                            0.49999999999999994,
                            0.5,
                            0.7,
                            1.0 - std::numeric_limits<double>::epsilon(),
                            -0.1,
                            -0.49999999999999994,
@@ skipping 749 matching lines @@
   r.Goto(&merge);
   r.Bind(&merge);
   Node* phi = r.Phi(MachineRepresentation::kWord32, fa, fb);
   r.Return(phi);
   CHECK_EQ(1, r.Call(1));
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8