[libc-commits] [libc] [llvm] [libc][complex] Testing infra for MPC (PR #121261)

[Nick Desaulniers via libc-commits]

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@@ -0,0 +1,342 @@
+//===-- MPCommon.h ----------------------------------------------*- 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_UTILS_MPFRWRAPPER_MPCOMMON_H
+#define LLVM_LIBC_UTILS_MPFRWRAPPER_MPCOMMON_H
+
+#include "src/__support/CPP/string.h"
+#include "src/__support/CPP/type_traits.h"
+#include "src/__support/FPUtil/FPBits.h"
+#include "src/__support/macros/config.h"
+#include "test/UnitTest/RoundingModeUtils.h"
+
+#include <stdint.h>
+
+#include "mpfr_inc.h"
+
+#ifdef LIBC_TYPES_FLOAT128_IS_NOT_LONG_DOUBLE
+extern "C" {
+int mpfr_set_float128(mpfr_ptr, float128, mpfr_rnd_t);
+float128 mpfr_get_float128(mpfr_srcptr, mpfr_rnd_t);
+}
+#endif
+
+namespace LIBC_NAMESPACE_DECL {
+namespace testing {
+namespace mpfr {
+
+template <typename T> using FPBits = LIBC_NAMESPACE::fputil::FPBits<T>;
+using LIBC_NAMESPACE::fputil::testing::RoundingMode;
+
+// A precision value which allows sufficiently large additional
+// precision compared to the floating point precision.
+template <typename T> struct ExtraPrecision;
+
+#ifdef LIBC_TYPES_HAS_FLOAT16
+template <> struct ExtraPrecision<float16> {
+  static constexpr unsigned int VALUE = 128;
+};
+#endif
+
+template <> struct ExtraPrecision<float> {
+  static constexpr unsigned int VALUE = 128;
+};
+
+template <> struct ExtraPrecision<double> {
+  static constexpr unsigned int VALUE = 256;
+};
+
+template <> struct ExtraPrecision<long double> {
+#ifdef LIBC_TYPES_LONG_DOUBLE_IS_FLOAT128
+  static constexpr unsigned int VALUE = 512;
+#else
+  static constexpr unsigned int VALUE = 256;
+#endif
+};
+
+#if defined(LIBC_TYPES_FLOAT128_IS_NOT_LONG_DOUBLE)
+template <> struct ExtraPrecision<float128> {
+  static constexpr unsigned int VALUE = 512;
+};
+#endif // LIBC_TYPES_FLOAT128_IS_NOT_LONG_DOUBLE
+
+// If the ulp tolerance is less than or equal to 0.5, we would check that the
+// result is rounded correctly with respect to the rounding mode by using the
+// same precision as the inputs.
+template <typename T>
+static inline unsigned int get_precision(double ulp_tolerance) {
+  if (ulp_tolerance <= 0.5) {
+    return LIBC_NAMESPACE::fputil::FPBits<T>::FRACTION_LEN + 1;
+  } else {
+    return ExtraPrecision<T>::VALUE;
+  }
+}
+
+static inline mpfr_rnd_t get_mpfr_rounding_mode(RoundingMode mode) {
+  switch (mode) {
+  case RoundingMode::Upward:
+    return MPFR_RNDU;
+    break;
+  case RoundingMode::Downward:
+    return MPFR_RNDD;
+    break;
+  case RoundingMode::TowardZero:
+    return MPFR_RNDZ;
+    break;
+  case RoundingMode::Nearest:
+    return MPFR_RNDN;
+    break;
+  }
+  __builtin_unreachable();
+}
+
+class MPFRNumber {
----------------
nickdesaulniers wrote:

Then perhaps MPCommon.h should just be named MPFRNumber.h?

https://github.com/llvm/llvm-project/pull/121261