1 files changed, 84 insertions, 0 deletions
diff --git a/llvm/lib/Support/Unix/Host.inc b/llvm/lib/Support/Unix/Host.inc
new file mode 100644
index 000000000000..17d78dc18be7
--- /dev/null
+++ b/llvm/lib/Support/Unix/Host.inc
@@ -0,0 +1,84 @@
+//===- llvm/Support/Unix/Host.inc -------------------------------*- 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
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the UNIX Host support.
+//
+//===----------------------------------------------------------------------===//
+
+//===----------------------------------------------------------------------===//
+//=== WARNING: Implementation here must contain only generic UNIX code that
+//===          is guaranteed to work on *all* UNIX variants.
+//===----------------------------------------------------------------------===//
+
+#include "Unix.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/Config/config.h"
+#include <cctype>
+#include <string>
+#include <sys/utsname.h>
+
+using namespace llvm;
+
+static std::string getOSVersion() {
+  struct utsname info;
+
+  if (uname(&info))
+    return "";
+
+  return info.release;
+}
+
+static std::string updateTripleOSVersion(std::string TargetTripleString) {
+  // On darwin, we want to update the version to match that of the target.
+  std::string::size_type DarwinDashIdx = TargetTripleString.find("-darwin");
+  if (DarwinDashIdx != std::string::npos) {
+    TargetTripleString.resize(DarwinDashIdx + strlen("-darwin"));
+    TargetTripleString += getOSVersion();
+    return TargetTripleString;
+  }
+  std::string::size_type MacOSDashIdx = TargetTripleString.find("-macos");
+  if (MacOSDashIdx != std::string::npos) {
+    TargetTripleString.resize(MacOSDashIdx);
+    // Reset the OS to darwin as the OS version from `uname` doesn't use the
+    // macOS version scheme.
+    TargetTripleString += "-darwin";
+    TargetTripleString += getOSVersion();
+  }
+  // On AIX, the AIX version and release should be that of the current host
+  // unless if the version has already been specified.
+  if (Triple(LLVM_HOST_TRIPLE).getOS() == Triple::AIX) {
+    Triple TT(TargetTripleString);
+    if (TT.getOS() == Triple::AIX && !TT.getOSMajorVersion()) {
+      struct utsname name;
+      if (uname(&name) != -1) {
+        std::string NewOSName = Triple::getOSTypeName(Triple::AIX);
+        NewOSName += name.version;
+        NewOSName += '.';
+        NewOSName += name.release;
+        NewOSName += ".0.0";
+        TT.setOSName(NewOSName);
+        return TT.str();
+      }
+    }
+  }
+  return TargetTripleString;
+}
+
+std::string sys::getDefaultTargetTriple() {
+  std::string TargetTripleString =
+      updateTripleOSVersion(LLVM_DEFAULT_TARGET_TRIPLE);
+
+  // Override the default target with an environment variable named by
+  // LLVM_TARGET_TRIPLE_ENV.
+#if defined(LLVM_TARGET_TRIPLE_ENV)
+  if (const char *EnvTriple = std::getenv(LLVM_TARGET_TRIPLE_ENV))
+    TargetTripleString = EnvTriple;
+#endif
+
+  return TargetTripleString;
+}