[libc-commits] [libc] [llvm] [libc][math] Impl bfloat16 lgamma function. (PR #199312)

[via libc-commits]

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@@ -0,0 +1,106 @@
+//===-- Unittests for lgammabf16 ------------------------------------------===//
+//
+// 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/math/lgammabf16.h"
+#include "test/UnitTest/FEnvSafeTest.h"
+#include "test/UnitTest/FPMatcher.h"
+#include "test/UnitTest/Test.h"
+
+class LlvmLibcLgammaBf16Test : public LIBC_NAMESPACE::testing::FEnvSafeTest {
+  DECLARE_SPECIAL_CONSTANTS(bfloat16)
+
+public:
+  void test_special_numbers() {
+    // aNaN -> aNaN, no exception
+    EXPECT_FP_EQ_ALL_ROUNDING(aNaN, LIBC_NAMESPACE::lgammabf16(aNaN));
+    EXPECT_MATH_ERRNO(0);
+
+    // sNaN -> aNaN, FE_INVALID
+    EXPECT_FP_EQ_WITH_EXCEPTION(aNaN, LIBC_NAMESPACE::lgammabf16(sNaN),
+                                FE_INVALID);
+    EXPECT_MATH_ERRNO(0);
+
+    // +Inf -> +Inf
+    EXPECT_FP_EQ_ALL_ROUNDING(inf, LIBC_NAMESPACE::lgammabf16(inf));
+    EXPECT_MATH_ERRNO(0);
+
+    // -Inf -> +Inf
+    EXPECT_FP_EQ_ALL_ROUNDING(inf, LIBC_NAMESPACE::lgammabf16(neg_inf));
+    EXPECT_MATH_ERRNO(0);
+
+    // +-0 -> +Inf, pole error
+    EXPECT_FP_EQ_WITH_EXCEPTION_ALL_ROUNDING(
+        inf, LIBC_NAMESPACE::lgammabf16(zero), FE_DIVBYZERO);
+    EXPECT_MATH_ERRNO(ERANGE);
+
+    EXPECT_FP_EQ_WITH_EXCEPTION_ALL_ROUNDING(
+        inf, LIBC_NAMESPACE::lgammabf16(neg_zero), FE_DIVBYZERO);
+    EXPECT_MATH_ERRNO(ERANGE);
+
+    // lgamma(1) = lgamma(2) = 0
+    EXPECT_FP_EQ_ALL_ROUNDING(zero, LIBC_NAMESPACE::lgammabf16(bfloat16(1.0f)));
+    EXPECT_MATH_ERRNO(0);
+
+    EXPECT_FP_EQ_ALL_ROUNDING(zero, LIBC_NAMESPACE::lgammabf16(bfloat16(2.0f)));
+    EXPECT_MATH_ERRNO(0);
+
+    // Negative integers -> +Inf, pole error
+    EXPECT_FP_EQ_WITH_EXCEPTION_ALL_ROUNDING(
+        inf, LIBC_NAMESPACE::lgammabf16(bfloat16(-1.0f)), FE_DIVBYZERO);
+    EXPECT_MATH_ERRNO(ERANGE);
+
+    EXPECT_FP_EQ_WITH_EXCEPTION_ALL_ROUNDING(
+        inf, LIBC_NAMESPACE::lgammabf16(bfloat16(-2.0f)), FE_DIVBYZERO);
+    EXPECT_MATH_ERRNO(ERANGE);
+  }
+  void test_negative_integers() {
+    // More negative integer poles -> +Inf, pole error
+    EXPECT_FP_EQ_WITH_EXCEPTION_ALL_ROUNDING(
+        inf, LIBC_NAMESPACE::lgammabf16(bfloat16(-3.0f)), FE_DIVBYZERO);
+    EXPECT_MATH_ERRNO(ERANGE);
+    EXPECT_FP_EQ_WITH_EXCEPTION_ALL_ROUNDING(
+        inf, LIBC_NAMESPACE::lgammabf16(bfloat16(-4.0f)), FE_DIVBYZERO);
+    EXPECT_MATH_ERRNO(ERANGE);
+    EXPECT_FP_EQ_WITH_EXCEPTION_ALL_ROUNDING(
+        inf, LIBC_NAMESPACE::lgammabf16(bfloat16(-10.0f)), FE_DIVBYZERO);
+    EXPECT_MATH_ERRNO(ERANGE);
+    EXPECT_FP_EQ_WITH_EXCEPTION_ALL_ROUNDING(
+        inf, LIBC_NAMESPACE::lgammabf16(bfloat16(-100.0f)), FE_DIVBYZERO);
+    EXPECT_MATH_ERRNO(ERANGE);
+  }
+
----------------
Sukumarsawant wrote:

Let's include them completely in one function or put all the negatives in the negative function 

https://github.com/llvm/llvm-project/pull/199312