Add llvm::sys::getHostTriple and remove
llvm::sys::getOS{Name,Version}.

Right now the implementation just derives from LLVM_HOSTTRIPLE (which
is wrong, but it doesn't look like we have a define for the target
triple). Ideally this routine would actually be able to compute the
triple for targets we care about.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@68118 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/System/Unix/Host.inc b/lib/System/Unix/Host.inc
index 1bd6da5..fb319fd 100644
--- a/lib/System/Unix/Host.inc
+++ b/lib/System/Unix/Host.inc
@@ -23,16 +23,7 @@
 
 using namespace llvm;
 
-std::string llvm::sys::getOSName() {
-  struct utsname info;
-
-  if (uname(&info))
-    return "";
-
-  return info.sysname;
-}
-
-std::string llvm::sys::getOSVersion() {
+static std::string getOSVersion() {
   struct utsname info;
 
   if (uname(&info))
@@ -40,3 +31,28 @@
 
   return info.release;
 }
+
+std::string sys::getHostTriple() {
+  // FIXME: Derive more directly instead of relying on the autoconf
+  // generated variable.
+
+  std::string Triple = LLVM_HOSTTRIPLE;
+
+  // Force i<N>86 to i386.
+  if (Triple[0] == 'i' && isdigit(Triple[1]) && 
+      Triple[2] == '8' && Triple[3] == '6')
+    Triple[1] = '3';
+
+  // On darwin, we want to update the version to match that of the
+  // host.    
+  std::string::size_type DarwinDashIdx = Triple.find("-darwin");
+  if (DarwinDashIdx != std::string::npos) {
+    Triple.resize(DarwinDashIdx + strlen("-darwin"));
+    
+    // Only add the major part of the os version.
+    std::string Version = getOSVersion();
+    Triple += Version.substr(0, Version.find('.'));
+  }
+
+  return Triple;
+}