[libc-commits] [libc] [libc][math] Implement a fast pass for atan2f128 with 1ULP error using DyadicFloat<128>. (PR #133150)

[via libc-commits]

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@@ -0,0 +1,28 @@
+//===-- Unittests for atan2f128 -------------------------------------------===//
+//
+// 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/integer_literals.h"
+#include "src/math/atan2f128.h"
+#include "test/UnitTest/FPMatcher.h"
+#include "test/UnitTest/Test.h"
+
+using LlvmLibcAtan2f128Test = LIBC_NAMESPACE::testing::FPTest<float128>;
+
+TEST_F(LlvmLibcAtan2f128Test, SpecialNumbers) {
+  EXPECT_FP_EQ_ALL_ROUNDING(aNaN, LIBC_NAMESPACE::atan2f128(aNaN, zero));
+  EXPECT_FP_EQ_ALL_ROUNDING(aNaN, LIBC_NAMESPACE::atan2f128(1.0, aNaN));
+  EXPECT_FP_EQ_ALL_ROUNDING(0.0, LIBC_NAMESPACE::atan2f128(zero, zero));
+  EXPECT_FP_EQ_ALL_ROUNDING(-0.0, LIBC_NAMESPACE::atan2f128(-0.0, zero));
+  EXPECT_FP_EQ_ALL_ROUNDING(0.0, LIBC_NAMESPACE::atan2f128(1.0, inf));
+  EXPECT_FP_EQ_ALL_ROUNDING(-0.0, LIBC_NAMESPACE::atan2f128(-1.0, inf));
----------------
overmighty wrote:

```suggestion
  EXPECT_FP_EQ_ALL_ROUNDING(aNaN, LIBC_NAMESPACE::atan2f128(aNaN, zero));
  EXPECT_FP_EQ_ALL_ROUNDING(aNaN, LIBC_NAMESPACE::atan2f128(1.0, aNaN));
  EXPECT_FP_EQ_ALL_ROUNDING(zero, LIBC_NAMESPACE::atan2f128(zero, zero));
  EXPECT_FP_EQ_ALL_ROUNDING(neg_zero, LIBC_NAMESPACE::atan2f128(neg_zero, zero));
  EXPECT_FP_EQ_ALL_ROUNDING(zero, LIBC_NAMESPACE::atan2f128(1.0, inf));
  EXPECT_FP_EQ_ALL_ROUNDING(neg_zero, LIBC_NAMESPACE::atan2f128(-1.0, inf));
```

https://github.com/llvm/llvm-project/pull/133150