[libc-commits] [libc] [llvm] [libc][math] Refactor tanpif16 to header-only (PR #181240)

[Muhammad Bassiouni via libc-commits]

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@@ -0,0 +1,126 @@
+//===-- Implementation header for tanpif16 ----------------------*- C++ -*-===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+#ifndef LLVM_LIBC_SRC___SUPPORT_MATH_TANPIF16_H
+#define LLVM_LIBC_SRC___SUPPORT_MATH_TANPIF16_H
+#include "include/llvm-libc-macros/float16-macros.h"
+#ifdef LIBC_TYPES_HAS_FLOAT16
+
+#include "hdr/errno_macros.h"
+#include "hdr/fenv_macros.h"
+#include "sincosf16_utils.h"
+#include "src/__support/FPUtil/FEnvImpl.h"
+#include "src/__support/FPUtil/FPBits.h"
+#include "src/__support/FPUtil/cast.h"
+#include "src/__support/FPUtil/except_value_utils.h"
+#include "src/__support/FPUtil/multiply_add.h"
+#include "src/__support/macros/optimization.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+namespace math {
+
+namespace tanpif16_internal {
+#ifndef LIBC_MATH_HAS_SKIP_ACCURATE_PASS
+LIBC_INLINE_VAR constexpr size_t N_EXCEPTS = 21;
+
+LIBC_INLINE_VAR constexpr fputil::ExceptValues<float16, N_EXCEPTS>
+    TANPIF16_EXCEPTS{{
+        // (input, RZ output, RU offset, RD offset, RN offset)
+        {0x07f2, 0x0e3d, 1, 0, 0}, {0x086a, 0x0eee, 1, 0, 1},
+        {0x08db, 0x0fa0, 1, 0, 0}, {0x094c, 0x1029, 1, 0, 0},
+        {0x0b10, 0x118c, 1, 0, 0}, {0x1ce0, 0x23a8, 1, 0, 1},
+        {0x1235, 0x18e0, 1, 0, 0}, {0x2579, 0x2c4e, 1, 0, 0},
+        {0x28b2, 0x2f68, 1, 0, 1}, {0x2a43, 0x30f4, 1, 0, 1},
+        {0x31b7, 0x3907, 1, 0, 0}, {0x329d, 0x3a12, 1, 0, 1},
+        {0x34f1, 0x3dd7, 1, 0, 0}, {0x3658, 0x41ee, 1, 0, 0},
+        {0x38d4, 0xc1ee, 0, 1, 0}, {0x3d96, 0x41ee, 1, 0, 0},
+        {0x3e6a, 0xc1ee, 0, 1, 0}, {0x40cb, 0x41ee, 1, 0, 0},
+        {0x4135, 0xc1ee, 0, 1, 0}, {0x42cb, 0x41ee, 1, 0, 0},
+        {0x4335, 0xc1ee, 0, 1, 0},
+    }};
+#endif // !LIBC_MATH_HAS_SKIP_ACCURATE_PASS
+} // namespace tanpif16_internal
+
+LIBC_INLINE constexpr float16 tanpif16(float16 x) {
----------------
bassiounix wrote:

This can't be `constexpr`
```suggestion
LIBC_INLINE float16 tanpif16(float16 x) {
```

https://github.com/llvm/llvm-project/pull/181240