1 files changed, 148 insertions, 0 deletions
diff --git a/tests/math_data_test.h b/tests/math_data_test.h
new file mode 100644
index 000000000..f3d25ef21
--- /dev/null
+++ b/tests/math_data_test.h
@@ -0,0 +1,148 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <gtest/gtest.h>
+
+#include <fenv.h>
+
+template <typename RT, typename T1>
+struct data_1_1_t {
+  RT expected;
+  T1 input;
+};
+
+template <typename RT, typename T1, typename T2>
+struct data_1_2_t {
+  RT expected;
+  T1 input1;
+  T2 input2;
+};
+
+template <typename RT1, typename RT2, typename T>
+struct data_2_1_t {
+  RT1 expected1;
+  RT2 expected2;
+  T input;
+};
+
+template <typename T> union fp_u;
+
+template <> union fp_u<float> {
+  float value;
+  struct {
+    unsigned frac:23;
+    unsigned exp:8;
+    unsigned sign:1;
+  } bits;
+  uint32_t sign_magnitude;
+};
+
+template <> union fp_u<double> {
+  double value;
+  struct {
+    unsigned fracl;
+    unsigned frach:20;
+    unsigned exp:11;
+    unsigned sign:1;
+  } bits;
+  uint64_t sign_magnitude;
+};
+
+// TODO: long double.
+
+template <typename T>
+static inline auto SignAndMagnitudeToBiased(const T& value) -> decltype(fp_u<T>::sign_magnitude) {
+  fp_u<T> u;
+  u.value = value;
+  if (u.bits.sign) {
+    return ~u.sign_magnitude + 1;
+  } else {
+    u.bits.sign = 1;
+    return u.sign_magnitude;
+  }
+}
+
+// Based on the existing googletest implementation, which uses a fixed 4 ulp bound.
+template <typename T>
+size_t UlpDistance(T lhs, T rhs) {
+  const auto biased1 = SignAndMagnitudeToBiased(lhs);
+  const auto biased2 = SignAndMagnitudeToBiased(rhs);
+  return (biased1 >= biased2) ? (biased1 - biased2) : (biased2 - biased1);
+}
+
+template <size_t ULP, typename T>
+struct FpUlpEq {
+  ::testing::AssertionResult operator()(const char* /* expected_expression */,
+                                        const char* /* actual_expression */,
+                                        T expected,
+                                        T actual) {
+    if (!isnan(expected) && !isnan(actual) && UlpDistance(expected, actual) <= ULP) {
+      return ::testing::AssertionSuccess();
+    }
+
+    // Output the actual and expected values as hex floating point.
+    char expected_str[64];
+    char actual_str[64];
+    snprintf(expected_str, sizeof(expected_str), "%a", expected);
+    snprintf(actual_str, sizeof(actual_str), "%a", actual);
+
+    return ::testing::AssertionFailure()
+        << "expected (" << expected_str << ") != actual (" << actual_str << ")";
+  }
+};
+
+// Runs through the array 'data' applying 'f' to each of the input values
+// and asserting that the result is within ULP ulps of the expected value.
+// For testing a (double) -> double function like sin(3).
+template <size_t ULP, typename RT, typename T, size_t N>
+void DoMathDataTest(data_1_1_t<RT, T> (&data)[N], RT f(T)) {
+  fesetenv(FE_DFL_ENV);
+  FpUlpEq<ULP, RT> predicate;
+  for (size_t i = 0; i < N; ++i) {
+    EXPECT_PRED_FORMAT2(predicate,
+                        data[i].expected, f(data[i].input)) << "Failed on element " << i;
+  }
+}
+
+// Runs through the array 'data' applying 'f' to each of the pairs of input values
+// and asserting that the result is within ULP ulps of the expected value.
+// For testing a (double, double) -> double function like pow(3).
+template <size_t ULP, typename RT, typename T1, typename T2, size_t N>
+void DoMathDataTest(data_1_2_t<RT, T1, T2> (&data)[N], RT f(T1, T2)) {
+  fesetenv(FE_DFL_ENV);
+  FpUlpEq<ULP, RT> predicate;
+  for (size_t i = 0; i < N; ++i) {
+    EXPECT_PRED_FORMAT2(predicate,
+                        data[i].expected, f(data[i].input1, data[i].input2)) << "Failed on element " << i;
+  }
+}
+
+// Runs through the array 'data' applying 'f' to each of the input values
+// and asserting that the results are within ULP ulps of the expected values.
+// For testing a (double, double*, double*) -> void function like sincos(3).
+template <size_t ULP, typename RT1, typename RT2, typename T1, size_t N>
+void DoMathDataTest(data_2_1_t<RT1, RT2, T1> (&data)[N], void f(T1, RT1*, RT2*)) {
+  fesetenv(FE_DFL_ENV);
+  FpUlpEq<ULP, RT1> predicate1;
+  FpUlpEq<ULP, RT2> predicate2;
+  for (size_t i = 0; i < N; ++i) {
+    RT1 out1;
+    RT2 out2;
+    f(data[i].input, &out1, &out2);
+    EXPECT_PRED_FORMAT2(predicate1, data[i].expected1, out1) << "Failed on element " << i;
+    EXPECT_PRED_FORMAT2(predicate2, data[i].expected2, out2) << "Failed on element " << i;
+  }
+}