[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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overmighty wrote:

Based on the `exp2f` smoke test. Not sure why `errno` is only checked in some cases.

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