[libc] Add implementations of fmax, fmaxf, and fmaxl.
Summary: Add implementations of fmax, fmaxf, and fmaxl.
Reviewers: sivachandra
Subscribers: mgorny, tschuett, libc-commits, ecnelises
Tags: #libc-project
Differential Revision: https://reviews.llvm.org/D84385
diff --git a/libc/config/linux/aarch64/entrypoints.txt b/libc/config/linux/aarch64/entrypoints.txt
index 4a0aa28..6a1ff3b 100644
--- a/libc/config/linux/aarch64/entrypoints.txt
+++ b/libc/config/linux/aarch64/entrypoints.txt
@@ -32,6 +32,9 @@
libc.src.math.floor
libc.src.math.floorf
libc.src.math.floorl
+ libc.src.math.fmax
+ libc.src.math.fmaxf
+ libc.src.math.fmaxl
libc.src.math.fmin
libc.src.math.fminf
libc.src.math.fminl
diff --git a/libc/config/linux/api.td b/libc/config/linux/api.td
index 7fc199e..1ec1a02 100644
--- a/libc/config/linux/api.td
+++ b/libc/config/linux/api.td
@@ -163,6 +163,9 @@
"floor",
"floorf",
"floorl",
+ "fmax",
+ "fmaxf",
+ "fmaxl",
"fmin",
"fminf",
"fminl",
diff --git a/libc/config/linux/x86_64/entrypoints.txt b/libc/config/linux/x86_64/entrypoints.txt
index 04acfb3..b20f58c 100644
--- a/libc/config/linux/x86_64/entrypoints.txt
+++ b/libc/config/linux/x86_64/entrypoints.txt
@@ -68,6 +68,9 @@
libc.src.math.fmin
libc.src.math.fminf
libc.src.math.fminl
+ libc.src.math.fmax
+ libc.src.math.fmaxf
+ libc.src.math.fmaxl
libc.src.math.frexp
libc.src.math.frexpf
libc.src.math.frexpl
diff --git a/libc/spec/stdc.td b/libc/spec/stdc.td
index cdeee89..6a11b00 100644
--- a/libc/spec/stdc.td
+++ b/libc/spec/stdc.td
@@ -209,6 +209,10 @@
FunctionSpec<"fminf", RetValSpec<FloatType>, [ArgSpec<FloatType>, ArgSpec<FloatType>]>,
FunctionSpec<"fminl", RetValSpec<LongDoubleType>, [ArgSpec<LongDoubleType>, ArgSpec<LongDoubleType>]>,
+ FunctionSpec<"fmax", RetValSpec<DoubleType>, [ArgSpec<DoubleType>, ArgSpec<DoubleType>]>,
+ FunctionSpec<"fmaxf", RetValSpec<FloatType>, [ArgSpec<FloatType>, ArgSpec<FloatType>]>,
+ FunctionSpec<"fmaxl", RetValSpec<LongDoubleType>, [ArgSpec<LongDoubleType>, ArgSpec<LongDoubleType>]>,
+
FunctionSpec<"frexp", RetValSpec<DoubleType>, [ArgSpec<DoubleType>, ArgSpec<IntPtr>]>,
FunctionSpec<"frexpf", RetValSpec<FloatType>, [ArgSpec<FloatType>, ArgSpec<IntPtr>]>,
FunctionSpec<"frexpl", RetValSpec<LongDoubleType>, [ArgSpec<LongDoubleType>, ArgSpec<IntPtr>]>,
diff --git a/libc/src/math/CMakeLists.txt b/libc/src/math/CMakeLists.txt
index d2d6948..da18aeb 100644
--- a/libc/src/math/CMakeLists.txt
+++ b/libc/src/math/CMakeLists.txt
@@ -449,3 +449,39 @@
COMPILE_OPTIONS
-O2
)
+
+add_entrypoint_object(
+ fmax
+ SRCS
+ fmax.cpp
+ HDRS
+ fmax.h
+ DEPENDS
+ libc.utils.FPUtil.fputil
+ COMPILE_OPTIONS
+ -O2
+)
+
+add_entrypoint_object(
+ fmaxf
+ SRCS
+ fmaxf.cpp
+ HDRS
+ fmaxf.h
+ DEPENDS
+ libc.utils.FPUtil.fputil
+ COMPILE_OPTIONS
+ -O2
+)
+
+add_entrypoint_object(
+ fmaxl
+ SRCS
+ fmaxl.cpp
+ HDRS
+ fmaxl.h
+ DEPENDS
+ libc.utils.FPUtil.fputil
+ COMPILE_OPTIONS
+ -O2
+)
diff --git a/libc/src/math/fmax.cpp b/libc/src/math/fmax.cpp
new file mode 100644
index 0000000..ba5d933
--- /dev/null
+++ b/libc/src/math/fmax.cpp
@@ -0,0 +1,18 @@
+//===-- Implementation of fmax function -----------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/__support/common.h"
+#include "utils/FPUtil/BasicOperations.h"
+
+namespace __llvm_libc {
+
+double LLVM_LIBC_ENTRYPOINT(fmax)(double x, double y) {
+ return fputil::fmax(x, y);
+}
+
+} // namespace __llvm_libc
diff --git a/libc/src/math/fmax.h b/libc/src/math/fmax.h
new file mode 100644
index 0000000..9f05798
--- /dev/null
+++ b/libc/src/math/fmax.h
@@ -0,0 +1,18 @@
+//===-- Implementation header for fmax --------------------------*- 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_SRC_MATH_FMAX_H
+#define LLVM_LIBC_SRC_MATH_FMAX_H
+
+namespace __llvm_libc {
+
+double fmax(double x, double y);
+
+} // namespace __llvm_libc
+
+#endif // LLVM_LIBC_SRC_MATH_FMAX_H
diff --git a/libc/src/math/fmaxf.cpp b/libc/src/math/fmaxf.cpp
new file mode 100644
index 0000000..5562904
--- /dev/null
+++ b/libc/src/math/fmaxf.cpp
@@ -0,0 +1,18 @@
+//===-- Implementation of fmaxf function ----------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/__support/common.h"
+#include "utils/FPUtil/BasicOperations.h"
+
+namespace __llvm_libc {
+
+float LLVM_LIBC_ENTRYPOINT(fmaxf)(float x, float y) {
+ return fputil::fmax(x, y);
+}
+
+} // namespace __llvm_libc
diff --git a/libc/src/math/fmaxf.h b/libc/src/math/fmaxf.h
new file mode 100644
index 0000000..e37df5c
--- /dev/null
+++ b/libc/src/math/fmaxf.h
@@ -0,0 +1,18 @@
+//===-- Implementation header for fmaxf -------------------------*- 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_SRC_MATH_FMAXF_H
+#define LLVM_LIBC_SRC_MATH_FMAXF_H
+
+namespace __llvm_libc {
+
+float fmaxf(float x, float y);
+
+} // namespace __llvm_libc
+
+#endif // LLVM_LIBC_SRC_MATH_FMAXF_H
diff --git a/libc/src/math/fmaxl.cpp b/libc/src/math/fmaxl.cpp
new file mode 100644
index 0000000..c944187
--- /dev/null
+++ b/libc/src/math/fmaxl.cpp
@@ -0,0 +1,18 @@
+//===-- Implementation of fmaxl function ----------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/__support/common.h"
+#include "utils/FPUtil/BasicOperations.h"
+
+namespace __llvm_libc {
+
+long double LLVM_LIBC_ENTRYPOINT(fmaxl)(long double x, long double y) {
+ return fputil::fmax(x, y);
+}
+
+} // namespace __llvm_libc
diff --git a/libc/src/math/fmaxl.h b/libc/src/math/fmaxl.h
new file mode 100644
index 0000000..41d80ba
--- /dev/null
+++ b/libc/src/math/fmaxl.h
@@ -0,0 +1,18 @@
+//===-- Implementation header for fmaxl -------------------------*- 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_SRC_MATH_FMAXL_H
+#define LLVM_LIBC_SRC_MATH_FMAXL_H
+
+namespace __llvm_libc {
+
+long double fmaxl(long double x, long double y);
+
+} // namespace __llvm_libc
+
+#endif // LLVM_LIBC_SRC_MATH_FMAXL_H
diff --git a/libc/test/src/math/CMakeLists.txt b/libc/test/src/math/CMakeLists.txt
index a6898b3..3bd40f6 100644
--- a/libc/test/src/math/CMakeLists.txt
+++ b/libc/test/src/math/CMakeLists.txt
@@ -472,4 +472,40 @@
libc.include.math
libc.src.math.fminl
libc.utils.FPUtil.fputil
-)
\ No newline at end of file
+)
+
+add_math_unittest(
+ fmaxf_test
+ SUITE
+ libc_math_unittests
+ SRCS
+ fmaxf_test.cpp
+ DEPENDS
+ libc.include.math
+ libc.src.math.fmaxf
+ libc.utils.FPUtil.fputil
+)
+
+add_math_unittest(
+ fmax_test
+ SUITE
+ libc_math_unittests
+ SRCS
+ fmax_test.cpp
+ DEPENDS
+ libc.include.math
+ libc.src.math.fmax
+ libc.utils.FPUtil.fputil
+)
+
+add_math_unittest(
+ fmaxl_test
+ SUITE
+ libc_math_unittests
+ SRCS
+ fmaxl_test.cpp
+ DEPENDS
+ libc.include.math
+ libc.src.math.fmaxl
+ libc.utils.FPUtil.fputil
+)
diff --git a/libc/test/src/math/fmax_test.cpp b/libc/test/src/math/fmax_test.cpp
new file mode 100644
index 0000000..8d1c6c2
--- /dev/null
+++ b/libc/test/src/math/fmax_test.cpp
@@ -0,0 +1,73 @@
+//===-- Unittests for fmax -----------------------------------------------===//
+//
+// 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
+//
+//===---------------------------------------------------------------------===//
+
+#include "include/math.h"
+#include "src/math/fmax.h"
+#include "utils/FPUtil/FPBits.h"
+#include "utils/UnitTest/Test.h"
+
+using FPBits = __llvm_libc::fputil::FPBits<double>;
+
+double nan = FPBits::buildNaN(1);
+double inf = FPBits::inf();
+double negInf = FPBits::negInf();
+
+TEST(FmaxTest, NaNArg) {
+ EXPECT_EQ(inf, __llvm_libc::fmax(nan, inf));
+ EXPECT_EQ(negInf, __llvm_libc::fmax(negInf, nan));
+ EXPECT_EQ(0.0, __llvm_libc::fmax(nan, 0.0));
+ EXPECT_EQ(-0.0, __llvm_libc::fmax(-0.0, nan));
+ EXPECT_EQ(-1.2345, __llvm_libc::fmax(nan, -1.2345));
+ EXPECT_EQ(1.2345, __llvm_libc::fmax(1.2345, nan));
+ EXPECT_NE(isnan(__llvm_libc::fmax(nan, nan)), 0);
+}
+
+TEST(FmaxTest, InfArg) {
+ EXPECT_EQ(inf, __llvm_libc::fmax(negInf, inf));
+ EXPECT_EQ(inf, __llvm_libc::fmax(inf, 0.0));
+ EXPECT_EQ(inf, __llvm_libc::fmax(-0.0, inf));
+ EXPECT_EQ(inf, __llvm_libc::fmax(inf, 1.2345));
+ EXPECT_EQ(inf, __llvm_libc::fmax(-1.2345, inf));
+}
+
+TEST(FmaxTest, NegInfArg) {
+ EXPECT_EQ(inf, __llvm_libc::fmax(inf, negInf));
+ EXPECT_EQ(0.0, __llvm_libc::fmax(negInf, 0.0));
+ EXPECT_EQ(-0.0, __llvm_libc::fmax(-0.0, negInf));
+ EXPECT_EQ(-1.2345, __llvm_libc::fmax(negInf, -1.2345));
+ EXPECT_EQ(1.2345, __llvm_libc::fmax(1.2345, negInf));
+}
+
+TEST(FmaxTest, BothZero) {
+ EXPECT_EQ(0.0, __llvm_libc::fmax(0.0, 0.0));
+ EXPECT_EQ(0.0, __llvm_libc::fmax(-0.0, 0.0));
+ EXPECT_EQ(0.0, __llvm_libc::fmax(0.0, -0.0));
+ EXPECT_EQ(-0.0, __llvm_libc::fmax(-0.0, -0.0));
+}
+
+TEST(FmaxTest, InDoubleRange) {
+ using UIntType = FPBits::UIntType;
+ constexpr UIntType count = 10000001;
+ constexpr UIntType step = UIntType(-1) / count;
+ for (UIntType i = 0, v = 0, w = UIntType(-1); i <= count;
+ ++i, v += step, w -= step) {
+ double x = FPBits(v), y = FPBits(w);
+ if (isnan(x) || isinf(x))
+ continue;
+ if (isnan(y) || isinf(y))
+ continue;
+ if ((x == 0) && (y == 0))
+ continue;
+
+ if (x > y) {
+ ASSERT_EQ(x, __llvm_libc::fmax(x, y));
+ } else {
+ ASSERT_EQ(y, __llvm_libc::fmax(x, y));
+ }
+ }
+}
diff --git a/libc/test/src/math/fmaxf_test.cpp b/libc/test/src/math/fmaxf_test.cpp
new file mode 100644
index 0000000..fe9eaad1
--- /dev/null
+++ b/libc/test/src/math/fmaxf_test.cpp
@@ -0,0 +1,73 @@
+//===-- Unittests for fmaxf -----------------------------------------------===//
+//
+// 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
+//
+//===---------------------------------------------------------------------===//
+
+#include "include/math.h"
+#include "src/math/fmaxf.h"
+#include "utils/FPUtil/FPBits.h"
+#include "utils/UnitTest/Test.h"
+
+using FPBits = __llvm_libc::fputil::FPBits<float>;
+
+float nan = FPBits::buildNaN(1);
+float inf = FPBits::inf();
+float negInf = FPBits::negInf();
+
+TEST(FmaxfTest, NaNArg) {
+ EXPECT_EQ(inf, __llvm_libc::fmaxf(nan, inf));
+ EXPECT_EQ(negInf, __llvm_libc::fmaxf(negInf, nan));
+ EXPECT_EQ(0.0f, __llvm_libc::fmaxf(nan, 0.0f));
+ EXPECT_EQ(-0.0f, __llvm_libc::fmaxf(-0.0f, nan));
+ EXPECT_EQ(-1.2345f, __llvm_libc::fmaxf(nan, -1.2345f));
+ EXPECT_EQ(1.2345f, __llvm_libc::fmaxf(1.2345f, nan));
+ EXPECT_NE(isnan(__llvm_libc::fmaxf(nan, nan)), 0);
+}
+
+TEST(FmaxfTest, InfArg) {
+ EXPECT_EQ(inf, __llvm_libc::fmaxf(negInf, inf));
+ EXPECT_EQ(inf, __llvm_libc::fmaxf(inf, 0.0f));
+ EXPECT_EQ(inf, __llvm_libc::fmaxf(-0.0f, inf));
+ EXPECT_EQ(inf, __llvm_libc::fmaxf(inf, 1.2345f));
+ EXPECT_EQ(inf, __llvm_libc::fmaxf(-1.2345f, inf));
+}
+
+TEST(FmaxfTest, NegInfArg) {
+ EXPECT_EQ(inf, __llvm_libc::fmaxf(inf, negInf));
+ EXPECT_EQ(0.0f, __llvm_libc::fmaxf(negInf, 0.0f));
+ EXPECT_EQ(-0.0f, __llvm_libc::fmaxf(-0.0f, negInf));
+ EXPECT_EQ(-1.2345f, __llvm_libc::fmaxf(negInf, -1.2345f));
+ EXPECT_EQ(1.2345f, __llvm_libc::fmaxf(1.2345f, negInf));
+}
+
+TEST(FmaxfTest, BothZero) {
+ EXPECT_EQ(0.0f, __llvm_libc::fmaxf(0.0f, 0.0f));
+ EXPECT_EQ(0.0f, __llvm_libc::fmaxf(-0.0f, 0.0f));
+ EXPECT_EQ(0.0f, __llvm_libc::fmaxf(0.0f, -0.0f));
+ EXPECT_EQ(-0.0f, __llvm_libc::fmaxf(-0.0f, -0.0f));
+}
+
+TEST(FmaxfTest, InFloatRange) {
+ using UIntType = FPBits::UIntType;
+ constexpr UIntType count = 10000001;
+ constexpr UIntType step = UIntType(-1) / count;
+ for (UIntType i = 0, v = 0, w = UIntType(-1); i <= count;
+ ++i, v += step, w -= step) {
+ float x = FPBits(v), y = FPBits(w);
+ if (isnan(x) || isinf(x))
+ continue;
+ if (isnan(y) || isinf(y))
+ continue;
+ if ((x == 0) && (y == 0))
+ continue;
+
+ if (x > y) {
+ ASSERT_EQ(x, __llvm_libc::fmaxf(x, y));
+ } else {
+ ASSERT_EQ(y, __llvm_libc::fmaxf(x, y));
+ }
+ }
+}
diff --git a/libc/test/src/math/fmaxl_test.cpp b/libc/test/src/math/fmaxl_test.cpp
new file mode 100644
index 0000000..9c7aa21
--- /dev/null
+++ b/libc/test/src/math/fmaxl_test.cpp
@@ -0,0 +1,73 @@
+//===-- Unittests for fmaxl -----------------------------------------------===//
+//
+// 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
+//
+//===---------------------------------------------------------------------===//
+
+#include "include/math.h"
+#include "src/math/fmaxl.h"
+#include "utils/FPUtil/FPBits.h"
+#include "utils/UnitTest/Test.h"
+
+using FPBits = __llvm_libc::fputil::FPBits<long double>;
+
+long double nan = FPBits::buildNaN(1);
+long double inf = FPBits::inf();
+long double negInf = FPBits::negInf();
+
+TEST(FmaxlTest, NaNArg) {
+ EXPECT_EQ(inf, __llvm_libc::fmaxl(nan, inf));
+ EXPECT_EQ(negInf, __llvm_libc::fmaxl(negInf, nan));
+ EXPECT_EQ(0.0L, __llvm_libc::fmaxl(nan, 0.0L));
+ EXPECT_EQ(-0.0L, __llvm_libc::fmaxl(-0.0L, nan));
+ EXPECT_EQ(-1.2345L, __llvm_libc::fmaxl(nan, -1.2345L));
+ EXPECT_EQ(1.2345L, __llvm_libc::fmaxl(1.2345L, nan));
+ EXPECT_NE(isnan(__llvm_libc::fmaxl(nan, nan)), 0);
+}
+
+TEST(FmaxlTest, InfArg) {
+ EXPECT_EQ(inf, __llvm_libc::fmaxl(negInf, inf));
+ EXPECT_EQ(inf, __llvm_libc::fmaxl(inf, 0.0L));
+ EXPECT_EQ(inf, __llvm_libc::fmaxl(-0.0L, inf));
+ EXPECT_EQ(inf, __llvm_libc::fmaxl(inf, 1.2345L));
+ EXPECT_EQ(inf, __llvm_libc::fmaxl(-1.2345L, inf));
+}
+
+TEST(FmaxlTest, NegInfArg) {
+ EXPECT_EQ(inf, __llvm_libc::fmaxl(inf, negInf));
+ EXPECT_EQ(0.0L, __llvm_libc::fmaxl(negInf, 0.0L));
+ EXPECT_EQ(-0.0L, __llvm_libc::fmaxl(-0.0L, negInf));
+ EXPECT_EQ(-1.2345L, __llvm_libc::fmaxl(negInf, -1.2345L));
+ EXPECT_EQ(1.2345L, __llvm_libc::fmaxl(1.2345L, negInf));
+}
+
+TEST(FmaxlTest, BothZero) {
+ EXPECT_EQ(0.0L, __llvm_libc::fmaxl(0.0L, 0.0L));
+ EXPECT_EQ(0.0L, __llvm_libc::fmaxl(-0.0L, 0.0L));
+ EXPECT_EQ(0.0L, __llvm_libc::fmaxl(0.0L, -0.0L));
+ EXPECT_EQ(-0.0L, __llvm_libc::fmaxl(-0.0L, -0.0L));
+}
+
+TEST(FmaxlTest, InLongDoubleRange) {
+ using UIntType = FPBits::UIntType;
+ constexpr UIntType count = 10000001;
+ constexpr UIntType step = UIntType(-1) / count;
+ for (UIntType i = 0, v = 0, w = UIntType(-1); i <= count;
+ ++i, v += step, w -= step) {
+ long double x = FPBits(v), y = FPBits(w);
+ if (isnan(x) || isinf(x))
+ continue;
+ if (isnan(y) || isinf(y))
+ continue;
+ if ((x == 0) && (y == 0))
+ continue;
+
+ if (x > y) {
+ ASSERT_EQ(x, __llvm_libc::fmaxl(x, y));
+ } else {
+ ASSERT_EQ(y, __llvm_libc::fmaxl(x, y));
+ }
+ }
+}
diff --git a/libc/utils/FPUtil/BasicOperations.h b/libc/utils/FPUtil/BasicOperations.h
index 2f86ddf..7885692 100644
--- a/libc/utils/FPUtil/BasicOperations.h
+++ b/libc/utils/FPUtil/BasicOperations.h
@@ -43,6 +43,25 @@
}
}
+template <typename T,
+ cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
+static inline T fmax(T x, T y) {
+ FPBits<T> bitx(x), bity(y);
+
+ if (bitx.isNaN()) {
+ return y;
+ } else if (bity.isNaN()) {
+ return x;
+ } else if (bitx.sign != bity.sign) {
+ // To make sure that fmax(+0, -0) == +0 == fmax(-0, +0), whenever x and
+ // y has different signs and both are not NaNs, we return the number
+ // with positive sign.
+ return (bitx.sign ? y : x);
+ } else {
+ return (x > y ? x : y);
+ }
+}
+
} // namespace fputil
} // namespace __llvm_libc