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

[Nick Desaulniers via llvm-commits]

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@@ -0,0 +1,356 @@
+//===-- Utils which wrap MPC ----------------------------------------------===//
+//
+// 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 "MPCUtils.h"
+
+#include "src/__support/CPP/array.h"
+#include "src/__support/CPP/stringstream.h"
+#include "utils/MPFRWrapper/MPCommon.h"
+
+#include <stdint.h>
+
+#include "mpc.h"
+
+template <typename T> using FPBits = LIBC_NAMESPACE::fputil::FPBits<T>;
+
+namespace LIBC_NAMESPACE_DECL {
+namespace testing {
+namespace mpc {
+
+static inline cpp::string str(RoundingMode mode) {
+  switch (mode) {
+  case RoundingMode::Upward:
+    return "MPFR_RNDU";
+  case RoundingMode::Downward:
+    return "MPFR_RNDD";
+  case RoundingMode::TowardZero:
+    return "MPFR_RNDZ";
+  case RoundingMode::Nearest:
+    return "MPFR_RNDN";
+  }
+}
+
+class MPCNumber {
+private:
+  unsigned int precision;
+  mpc_t value;
+  mpc_rnd_t mpc_rounding;
+
+public:
+  MPCNumber(unsigned int p) : precision(p), mpc_rounding(MPC_RNDNN) {
----------------
nickdesaulniers wrote:

```suggestion
  explicit MPCNumber(unsigned int p) : precision(p), mpc_rounding(MPC_RNDNN) {
```

Please use the `explicit` keyword for constructors that accept one argument, to avoid implicit conversions.

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