[libc-commits] [libc] [libc][math][c23] Add exp2m1f C23 math function (PR #86996)

[via libc-commits]

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@@ -0,0 +1,68 @@
+//===-- Unittests for exp2m1f ---------------------------------------------===//
+//
+// 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/errno/libc_errno.h"
+#include "src/math/exp2m1f.h"
+#include "test/UnitTest/FPMatcher.h"
+#include "test/UnitTest/Test.h"
+
+using LlvmLibcExp2m1fTest = LIBC_NAMESPACE::testing::FPTest<float>;
+using LIBC_NAMESPACE::fputil::testing::ForceRoundingMode;
+using LIBC_NAMESPACE::fputil::testing::RoundingMode;
+
+TEST_F(LlvmLibcExp2m1fTest, SpecialNumbers) {
+  LIBC_NAMESPACE::libc_errno = 0;
+
+  EXPECT_FP_EQ_ALL_ROUNDING(aNaN, LIBC_NAMESPACE::exp2m1f(aNaN));
+  EXPECT_MATH_ERRNO(0);
+  EXPECT_FP_EQ_ALL_ROUNDING(inf, LIBC_NAMESPACE::exp2m1f(inf));
+  EXPECT_MATH_ERRNO(0);
+  EXPECT_FP_EQ_ALL_ROUNDING(-1.0f, LIBC_NAMESPACE::exp2m1f(neg_inf));
+  EXPECT_MATH_ERRNO(0);
+  EXPECT_FP_EQ_ALL_ROUNDING(0.0f, LIBC_NAMESPACE::exp2m1f(0.0f));
+  EXPECT_MATH_ERRNO(0);
+  EXPECT_FP_EQ_ALL_ROUNDING(-0.0f, LIBC_NAMESPACE::exp2m1f(-0.0f));
+  EXPECT_MATH_ERRNO(0);
+
+  EXPECT_FP_EQ_ALL_ROUNDING(1.0f, LIBC_NAMESPACE::exp2m1f(1.0f));
+  EXPECT_FP_EQ_ALL_ROUNDING(-0.5f, LIBC_NAMESPACE::exp2m1f(-1.0f));
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lntue wrote:

It was the old test where we weren't so sure about what to do with errno.  For newer math tests, normally we can ignore no errno cases, and only test when special errno is set.

https://github.com/llvm/llvm-project/pull/86996