[builtins] Introduce proper Float64Log2 and Float64Log10 operators.

test/cctest/compiler/test-run-machops.cc

Index: test/cctest/compiler/test-run-machops.cc
diff --git a/test/cctest/compiler/test-run-machops.cc b/test/cctest/compiler/test-run-machops.cc
index 70e57cbd6814c1414609d08255d14cb29803dc94..ab5c7d90934bb21fe4a0fd7da59d4649c541619e 100644
--- a/test/cctest/compiler/test-run-machops.cc
+++ b/test/cctest/compiler/test-run-machops.cc
@@ -5546,6 +5546,35 @@ TEST(RunFloat64Log1p) {
   FOR_FLOAT64_INPUTS(i) { CHECK_DOUBLE_EQ(ieee754::log1p(*i), m.Call(*i)); }
 }
 
+TEST(RunFloat64Log2) {
+  BufferedRawMachineAssemblerTester<double> m(MachineType::Float64());
+  m.Return(m.Float64Log2(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(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::log2(*i), m.Call(*i)); }
+}
+
+TEST(RunFloat64Log10) {
+  BufferedRawMachineAssemblerTester<double> m(MachineType::Float64());
+  m.Return(m.Float64Log10(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(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(std::numeric_limits<double>::infinity(),
+                  m.Call(std::numeric_limits<double>::infinity()));
+  FOR_FLOAT64_INPUTS(i) { CHECK_DOUBLE_EQ(ieee754::log10(*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,