1 files changed, 74 insertions, 0 deletions
diff --git a/libc/test/src/math/DivTest.h b/libc/test/src/math/DivTest.h
new file mode 100644
index 000000000000..1cdc1398a1a1
--- /dev/null
+++ b/libc/test/src/math/DivTest.h
@@ -0,0 +1,74 @@
+//===-- Utility class to test different flavors of float div ----*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_TEST_SRC_MATH_DIVTEST_H
+#define LLVM_LIBC_TEST_SRC_MATH_DIVTEST_H
+
+#include "test/UnitTest/FEnvSafeTest.h"
+#include "test/UnitTest/FPMatcher.h"
+#include "test/UnitTest/Test.h"
+#include "utils/MPFRWrapper/MPFRUtils.h"
+
+namespace mpfr = LIBC_NAMESPACE::testing::mpfr;
+
+template <typename OutType, typename InType>
+class DivTest : public LIBC_NAMESPACE::testing::FEnvSafeTest {
+
+  struct InConstants {
+    DECLARE_SPECIAL_CONSTANTS(InType)
+  };
+
+  using InFPBits = typename InConstants::FPBits;
+  using InStorageType = typename InConstants::StorageType;
+
+  static constexpr InStorageType IN_MAX_NORMAL_U =
+      InFPBits::max_normal().uintval();
+  static constexpr InStorageType IN_MIN_NORMAL_U =
+      InFPBits::min_normal().uintval();
+  static constexpr InStorageType IN_MAX_SUBNORMAL_U =
+      InFPBits::max_subnormal().uintval();
+  static constexpr InStorageType IN_MIN_SUBNORMAL_U =
+      InFPBits::min_subnormal().uintval();
+
+public:
+  using DivFunc = OutType (*)(InType, InType);
+
+  void test_subnormal_range(DivFunc func) {
+    constexpr InStorageType COUNT = 100'001;
+    constexpr InStorageType STEP =
+        (IN_MAX_SUBNORMAL_U - IN_MIN_SUBNORMAL_U) / COUNT;
+    for (InStorageType i = 0, v = 0, w = IN_MAX_SUBNORMAL_U; i <= COUNT;
+         ++i, v += STEP, w -= STEP) {
+      InType x = InFPBits(v).get_val();
+      InType y = InFPBits(w).get_val();
+      mpfr::BinaryInput<InType> input{x, y};
+      EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Div, input, func(x, y),
+                                     0.5);
+    }
+  }
+
+  void test_normal_range(DivFunc func) {
+    constexpr InStorageType COUNT = 100'001;
+    constexpr InStorageType STEP = (IN_MAX_NORMAL_U - IN_MIN_NORMAL_U) / COUNT;
+    for (InStorageType i = 0, v = 0, w = IN_MAX_NORMAL_U; i <= COUNT;
+         ++i, v += STEP, w -= STEP) {
+      InType x = InFPBits(v).get_val();
+      InType y = InFPBits(w).get_val();
+      mpfr::BinaryInput<InType> input{x, y};
+      EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Div, input, func(x, y),
+                                     0.5);
+    }
+  }
+};
+
+#define LIST_DIV_TESTS(OutType, InType, func)                                  \
+  using LlvmLibcDivTest = DivTest<OutType, InType>;                            \
+  TEST_F(LlvmLibcDivTest, SubnormalRange) { test_subnormal_range(&func); }     \
+  TEST_F(LlvmLibcDivTest, NormalRange) { test_normal_range(&func); }
+
+#endif // LLVM_LIBC_TEST_SRC_MATH_DIVTEST_H