[libc-commits] [libc] [llvm] [libc][math][c++23] Add log10bf16 math function (PR #177269)

[via libc-commits]

================
@@ -0,0 +1,52 @@
+//===-- Unittests for BFloat16 log10(x) 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 "hdr/errno_macros.h"
+#include "hdr/fenv_macros.h"
+#include "src/__support/FPUtil/bfloat16.h"
+#include "src/__support/macros/properties/types.h"
+#include "src/math/log10bf16.h"
+#include "test/UnitTest/FEnvSafeTest.h"
+#include "test/UnitTest/FPMatcher.h"
+#include "test/UnitTest/Test.h"
+
+class LlvmLibcLogBf16Test : public LIBC_NAMESPACE::testing::FEnvSafeTest {
+  DECLARE_SPECIAL_CONSTANTS(bfloat16)
+
+public:
+  void test_special_numbers() {
+    EXPECT_FP_EQ_ALL_ROUNDING(aNaN, LIBC_NAMESPACE::log10bf16(aNaN));
+    EXPECT_MATH_ERRNO(0);
+
+    EXPECT_FP_EQ_WITH_EXCEPTION(aNaN, LIBC_NAMESPACE::log10bf16(sNaN),
+                                FE_INVALID);
+    EXPECT_MATH_ERRNO(0);
+
+    EXPECT_FP_EQ_ALL_ROUNDING(inf, LIBC_NAMESPACE::log10bf16(inf));
+    EXPECT_MATH_ERRNO(0);
+
+    EXPECT_FP_EQ_ALL_ROUNDING(aNaN, LIBC_NAMESPACE::log10bf16(neg_inf));
+    EXPECT_MATH_ERRNO(EDOM);
+
+    EXPECT_FP_EQ_WITH_EXCEPTION_ALL_ROUNDING(
+        neg_inf, LIBC_NAMESPACE::log10bf16(zero), FE_DIVBYZERO);
+    EXPECT_MATH_ERRNO(0);
+
+    EXPECT_FP_EQ_WITH_EXCEPTION_ALL_ROUNDING(
+        neg_inf, LIBC_NAMESPACE::log10bf16(neg_zero), FE_DIVBYZERO);
+    EXPECT_MATH_ERRNO(0);
+
+    EXPECT_FP_EQ_ALL_ROUNDING(zero, LIBC_NAMESPACE::log10bf16(bfloat16(1.0)));
+    EXPECT_MATH_ERRNO(0);
+
+    EXPECT_FP_EQ_ALL_ROUNDING(aNaN, LIBC_NAMESPACE::log10bf16(bfloat16(-1.0)));
----------------
Sukumarsawant wrote:

We can check both the flags for negative inputs 
```CPP
    // x < 0
    if (x_u > 0x8000U) {
      fputil::set_errno_if_required(EDOM);
      fputil::raise_except_if_required(FE_INVALID);
      return FPBits::quiet_nan().get_val();
    }
```

https://github.com/llvm/llvm-project/pull/177269