[libc][math] implement signbit and math macro unit tests (#97791)

This PR resolves #96322 and implements the `signbit` macro under a new
header `generic-math-macros.h`. This also removed the `TODO` in
`math-macros.h` and moves `isfinite`, `isinf`, and `isnan` to the same
generic maths header. Finally, a test file
`generic-math-macros_test.cpp` that adds coverage to the above 4 macros.

Fixes #96322.

libc/include/llvm-libc-macros/math-function-macros.h

@@ -12,5 +12,6 @@
 #define isfinite(x) __builtin_isfinite(x)
 #define isinf(x) __builtin_isinf(x)
 #define isnan(x) __builtin_isnan(x)
+#define signbit(x) __builtin_signbit(x)
 
 #endif // LLVM_LIBC_MACROS_MATH_FUNCTION_MACROS_H

libc/test/include/CMakeLists.txt

@@ -80,3 +80,183 @@ add_libc_test(
   DEPENDS
     libc.include.llvm-libc-macros.stdckdint_macros
 )
+
+add_libc_test(
+  signbit_test
+  SUITE
+    libc_include_tests
+  SRCS
+    signbit_test.cpp
+  DEPENDS
+    libc.include.llvm-libc-macros.math_function_macros
+)
+
+add_libc_test(
+  signbitf_test
+  SUITE
+    libc_include_tests
+  SRCS
+    signbitf_test.cpp
+  DEPENDS
+    libc.include.llvm-libc-macros.math_function_macros
+)
+
+add_libc_test(
+  signbitl_test
+  SUITE
+    libc_include_tests
+  SRCS
+    signbitl_test.cpp
+  DEPENDS
+    libc.include.llvm-libc-macros.math_function_macros
+)
+
+add_libc_test(
+  isnan_test
+  SUITE
+    libc_include_tests
+  SRCS
+    isnan_test.cpp
+  DEPENDS
+    libc.include.llvm-libc-macros.math_function_macros
+)
+
+add_libc_test(
+  isnanf_test
+  SUITE
+    libc_include_tests
+  SRCS
+    isnanf_test.cpp
+  DEPENDS
+    libc.include.llvm-libc-macros.math_function_macros
+)
+
+add_libc_test(
+  isnanl_test
+  SUITE
+    libc_include_tests
+  SRCS
+    isnanl_test.cpp
+  DEPENDS
+    libc.include.llvm-libc-macros.math_function_macros
+)
+
+add_libc_test(
+  isinf_test
+  SUITE
+    libc_include_tests
+  SRCS
+    isinf_test.cpp
+  DEPENDS
+    libc.include.llvm-libc-macros.math_function_macros
+)
+
+add_libc_test(
+  isinff_test
+  SUITE
+    libc_include_tests
+  SRCS
+    isinff_test.cpp
+  DEPENDS
+    libc.include.llvm-libc-macros.math_function_macros
+)
+
+add_libc_test(
+  isinfl_test
+  SUITE
+    libc_include_tests
+  SRCS
+    isinfl_test.cpp
+  DEPENDS
+    libc.include.llvm-libc-macros.math_function_macros
+)
+
+add_libc_test(
+  isfinite_test
+  SUITE
+    libc_include_tests
+  SRCS
+    isfinite_test.cpp
+  DEPENDS
+    libc.include.llvm-libc-macros.math_function_macros
+)
+
+add_libc_test(
+  isfinitef_test
+  SUITE
+    libc_include_tests
+  SRCS
+    isfinitef_test.cpp
+  DEPENDS
+    libc.include.llvm-libc-macros.math_function_macros
+)
+
+add_libc_test(
+  isfinitel_test
+  SUITE
+    libc_include_tests
+  SRCS
+    isfinitel_test.cpp
+  DEPENDS
+    libc.include.llvm-libc-macros.math_function_macros
+)
+
+add_libc_test(
+  signbit_c_test
+  C_TEST
+  UNIT_TEST_ONLY
+  SUITE
+    libc_include_tests
+  SRCS
+    signbit_test.c
+  COMPILE_OPTIONS
+    -Wall
+    -Werror
+  DEPENDS
+    libc.include.llvm-libc-macros.math_function_macros
+)
+
+add_libc_test(
+  isnan_c_test
+  C_TEST
+  UNIT_TEST_ONLY
+  SUITE
+    libc_include_tests
+  SRCS
+    isnan_test.c
+  COMPILE_OPTIONS
+    -Wall
+    -Werror
+  DEPENDS
+    libc.include.llvm-libc-macros.math_function_macros
+)
+
+add_libc_test(
+  isinf_c_test
+  C_TEST
+  UNIT_TEST_ONLY
+  SUITE
+    libc_include_tests
+  SRCS
+    isinf_test.c
+  COMPILE_OPTIONS
+    -Wall
+    -Werror
+  DEPENDS
+    libc.include.llvm-libc-macros.math_function_macros
+)  
+
+add_libc_test(
+  isfinite_c_test
+  C_TEST
+  UNIT_TEST_ONLY
+  SUITE
+    libc_include_tests
+  SRCS
+    isfinite_test.c
+  COMPILE_OPTIONS
+    -Wall
+    -Werror
+  DEPENDS
+    libc.include.llvm-libc-macros.math_function_macros
+)

libc/test/include/IsFiniteTest.h

@@ -0,0 +1,39 @@
+//===-- Utility class to test the isfinite macro [f|l] ----------*- 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_INCLUDE_MATH_ISFINITE_H
+#define LLVM_LIBC_TEST_INCLUDE_MATH_ISFINITE_H
+
+#include "test/UnitTest/FPMatcher.h"
+#include "test/UnitTest/Test.h"
+
+#include "include/llvm-libc-macros/math-function-macros.h"
+
+template <typename T>
+class IsFiniteTest : public LIBC_NAMESPACE::testing::Test {
+  DECLARE_SPECIAL_CONSTANTS(T)
+
+public:
+  typedef int (*IsFiniteFunc)(T);
+
+  void testSpecialNumbers(IsFiniteFunc func) {
+    EXPECT_EQ(func(inf), 0);
+    EXPECT_EQ(func(neg_inf), 0);
+    EXPECT_EQ(func(zero), 1);
+    EXPECT_EQ(func(neg_zero), 1);
+  }
+};
+
+#define LIST_ISFINITE_TESTS(T, func)                                           \
+  using LlvmLibcIsFiniteTest = IsFiniteTest<T>;                                \
+  TEST_F(LlvmLibcIsFiniteTest, SpecialNumbers) {                               \
+    auto isfinite_func = [](T x) { return func(x); };                          \
+    testSpecialNumbers(isfinite_func);                                         \
+  }
+
+#endif // LLVM_LIBC_TEST_INCLUDE_MATH_ISFINITE_H

libc/test/include/IsInfTest.h

@@ -0,0 +1,39 @@
+//===-- Utility class to test the isinf macro [f|l] -------------*- 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_INCLUDE_MATH_ISINF_H
+#define LLVM_LIBC_TEST_INCLUDE_MATH_ISINF_H
+
+#include "test/UnitTest/FPMatcher.h"
+#include "test/UnitTest/Test.h"
+
+#include "include/llvm-libc-macros/math-function-macros.h"
+
+template <typename T> class IsInfTest : public LIBC_NAMESPACE::testing::Test {
+
+  DECLARE_SPECIAL_CONSTANTS(T)
+
+public:
+  typedef int (*IsInfFunc)(T);
+
+  void testSpecialNumbers(IsInfFunc func) {
+    EXPECT_EQ(func(zero), 0);
+    EXPECT_EQ(func(neg_zero), 0);
+    EXPECT_EQ(func(inf), 1);
+    EXPECT_EQ(func(neg_inf), 1);
+  }
+};
+
+#define LIST_ISINF_TESTS(T, func)                                              \
+  using LlvmLibcIsInfTest = IsInfTest<T>;                                      \
+  TEST_F(LlvmLibcIsInfTest, SpecialNumbers) {                                  \
+    auto isinf_func = [](T x) { return func(x); };                             \
+    testSpecialNumbers(isinf_func);                                            \
+  }
+
+#endif // LLVM_LIBC_TEST_INCLUDE_MATH_ISINF_H

libc/test/include/IsNanTest.h

@@ -0,0 +1,39 @@
+//===-- Utility class to test the isnan macro [f|l] -------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license nanormation.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_TEST_INCLUDE_MATH_ISNAN_H
+#define LLVM_LIBC_TEST_INCLUDE_MATH_ISNAN_H
+
+#include "test/UnitTest/FPMatcher.h"
+#include "test/UnitTest/Test.h"
+
+#include "include/llvm-libc-macros/math-function-macros.h"
+
+template <typename T> class IsNanTest : public LIBC_NAMESPACE::testing::Test {
+
+  DECLARE_SPECIAL_CONSTANTS(T)
+
+public:
+  typedef int (*IsNanFunc)(T);
+
+  void testSpecialNumbers(IsNanFunc func) {
+    EXPECT_EQ(func(zero), 0);
+    EXPECT_EQ(func(neg_zero), 0);
+    EXPECT_EQ(func(aNaN), 1);
+    EXPECT_EQ(func(sNaN), 1);
+  }
+};
+
+#define LIST_ISNAN_TESTS(T, func)                                              \
+  using LlvmLibcIsNanTest = IsNanTest<T>;                                      \
+  TEST_F(LlvmLibcIsNanTest, SpecialNumbers) {                                  \
+    auto isnan_func = [](T x) { return func(x); };                             \
+    testSpecialNumbers(isnan_func);                                            \
+  }
+
+#endif // LLVM_LIBC_TEST_INCLUDE_MATH_ISNAN_H

libc/test/include/SignbitTest.h

@@ -0,0 +1,37 @@
+//===-- Utility class to test the signbit macro [f|l] -----------*- 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_INCLUDE_MATH_SIGNBIT_H
+#define LLVM_LIBC_TEST_INCLUDE_MATH_SIGNBIT_H
+
+#include "test/UnitTest/FPMatcher.h"
+#include "test/UnitTest/Test.h"
+
+#include "include/llvm-libc-macros/math-function-macros.h"
+
+template <typename T> class SignbitTest : public LIBC_NAMESPACE::testing::Test {
+
+  DECLARE_SPECIAL_CONSTANTS(T)
+
+public:
+  typedef int (*SignbitFunc)(T);
+
+  void testSpecialNumbers(SignbitFunc func) {
+    EXPECT_EQ(func(1), 0);
+    EXPECT_EQ(func(-1), 1);
+  }
+};
+
+#define LIST_SIGNBIT_TESTS(T, func)                                            \
+  using LlvmLibcSignbitTest = SignbitTest<T>;                                  \
+  TEST_F(LlvmLibcSignbitTest, SpecialNumbers) {                                \
+    auto signbit_func = [](T x) { return func(x); };                           \
+    testSpecialNumbers(signbit_func);                                          \
+  }
+
+#endif // LLVM_LIBC_TEST_INCLUDE_MATH_SIGNBIT_H

libc/test/include/isfinite_test.c

@@ -0,0 +1,22 @@
+//===-- Unittests for isfinite macro --------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDSList-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+#include "include/llvm-libc-macros/math-function-macros.h"
+
+#include <assert.h>
+
+// check if macro is defined
+#ifndef isfinite
+#error "isfinite macro is not defined"
+#else
+int main(void) {
+  assert(isfinite(1.0f));
+  assert(isfinite(1.0));
+  assert(isfinite(1.0L));
+  return 0;
+}
+#endif

libc/test/include/isfinite_test.cpp

@@ -0,0 +1,12 @@
+//===-- Unittest for isfinite[d] macro ------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDSList-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "IsFiniteTest.h"
+#include "include/llvm-libc-macros/math-function-macros.h"
+
+LIST_ISFINITE_TESTS(double, isfinite)

libc/test/include/isfinitef_test.cpp

@@ -0,0 +1,12 @@
+//===-- Unittest for isfinite[f] macro ------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDSList-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "IsFiniteTest.h"
+#include "include/llvm-libc-macros/math-function-macros.h"
+
+LIST_ISFINITE_TESTS(float, isfinite)

libc/test/include/isfinitel_test.cpp

@@ -0,0 +1,12 @@
+//===-- Unittest for isfinite[l] macro ------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDSList-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "IsFiniteTest.h"
+#include "include/llvm-libc-macros/math-function-macros.h"
+
+LIST_ISFINITE_TESTS(long double, isfinite)

libc/test/include/isinf_test.c

@@ -0,0 +1,22 @@
+//===-- Unittests for isinf macro -----------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDSList-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+#include "include/llvm-libc-macros/math-function-macros.h"
+
+#include <assert.h>
+
+// check if macro is defined
+#ifndef isinf
+#error "isinf macro is not defined"
+#else
+int main(void) {
+  assert(!isinf(1.0f));
+  assert(!isinf(1.0));
+  assert(!isinf(1.0L));
+  return 0;
+}
+#endif

libc/test/include/isinf_test.cpp

@@ -0,0 +1,12 @@
+//===-- Unittest for isinf[d] macro ---------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDSList-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "IsInfTest.h"
+#include "include/llvm-libc-macros/math-function-macros.h"
+
+LIST_ISINF_TESTS(double, isinf)

libc/test/include/isinff_test.cpp

@@ -0,0 +1,12 @@
+//===-- Unittest for isinf[f] macro ---------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDSList-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "IsInfTest.h"
+#include "include/llvm-libc-macros/math-function-macros.h"
+
+LIST_ISINF_TESTS(float, isinf)

libc/test/include/isinfl_test.cpp

@@ -0,0 +1,12 @@
+//===-- Unittest for isinf[l] macro ---------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDSList-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "IsInfTest.h"
+#include "include/llvm-libc-macros/math-function-macros.h"
+
+LIST_ISINF_TESTS(long double, isinf)

libc/test/include/isnan_test.c

@@ -0,0 +1,22 @@
+//===-- Unittests for isnan macro -----------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDSList-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+#include "include/llvm-libc-macros/math-function-macros.h"
+
+#include <assert.h>
+
+// check if macro is defined
+#ifndef isnan
+#error "isnan macro is not defined"
+#else
+int main(void) {
+  assert(!isnan(1.0f));
+  assert(!isnan(1.0));
+  assert(!isnan(1.0L));
+  return 0;
+}
+#endif

libc/test/include/isnan_test.cpp

@@ -0,0 +1,12 @@
+//===-- Unittest for isnan[l] macro ---------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDSList-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "IsNanTest.h"
+#include "include/llvm-libc-macros/math-function-macros.h"
+
+LIST_ISNAN_TESTS(double, isnan)

libc/test/include/isnanf_test.cpp

@@ -0,0 +1,12 @@
+//===-- Unittest for isnan[f] macro ---------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDSList-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "IsNanTest.h"
+#include "include/llvm-libc-macros/math-function-macros.h"
+
+LIST_ISNAN_TESTS(float, isnan)

libc/test/include/isnanl_test.cpp

@@ -0,0 +1,12 @@
+//===-- Unittest for isnan[l] macro ---------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDSList-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "IsNanTest.h"
+#include "include/llvm-libc-macros/math-function-macros.h"
+
+LIST_ISNAN_TESTS(long double, isnan)

libc/test/include/signbit_test.c

@@ -0,0 +1,25 @@
+//===-- Unittests for signbit macro ---------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDSList-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+#include "include/llvm-libc-macros/math-function-macros.h"
+
+#include <assert.h>
+
+// check if macro is defined
+#ifndef signbit
+#error "signbit macro is not defined"
+#else
+int main(void) {
+  assert(!signbit(1.0f));
+  assert(!signbit(1.0));
+  assert(!signbit(1.0L));
+  assert(signbit(-1.0f));
+  assert(signbit(-1.0));
+  assert(signbit(-1.0L));
+  return 0;
+}
+#endif

libc/test/include/signbit_test.cpp

@@ -0,0 +1,12 @@
+//===-- Unittest for signbit [d] macro ------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDSList-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "SignbitTest.h"
+#include "include/llvm-libc-macros/math-function-macros.h"
+
+LIST_SIGNBIT_TESTS(double, signbit)

libc/test/include/signbitf_test.cpp

@@ -0,0 +1,12 @@
+//===-- Unittests for signbit [f] macro -----------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDSList-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "SignbitTest.h"
+#include "include/llvm-libc-macros/math-function-macros.h"
+
+LIST_SIGNBIT_TESTS(float, signbit)

libc/test/include/signbitl_test.cpp

@@ -0,0 +1,12 @@
+//===-- Unittests for signbit[l] macro ------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDSList-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "SignbitTest.h"
+#include "include/llvm-libc-macros/math-function-macros.h"
+
+LIST_SIGNBIT_TESTS(long double, signbit)