Add Hurd triplet to LLVMSupport

This introduces GNU Hurd as a new target OS.

https://reviews.llvm.org/D54378

Index: llvm-toolchain-7-7.0.1~+rc2/include/llvm/ADT/Triple.h
===================================================================
--- llvm-toolchain-7-7.0.1~+rc2.orig/include/llvm/ADT/Triple.h
+++ llvm-toolchain-7-7.0.1~+rc2/include/llvm/ADT/Triple.h
@@ -182,7 +182,8 @@ public:
     Mesa3D,
     Contiki,
     AMDPAL,     // AMD PAL Runtime
-    LastOSType = AMDPAL
+    Hurd,       // GNU/Hurd
+    LastOSType = Hurd
   };
   enum EnvironmentType {
     UnknownEnvironment,
@@ -578,9 +579,15 @@ public:
     return getOS() == Triple::KFreeBSD;
   }
 
+  /// Tests whether the OS is Hurd.
+  bool isOSHurd() const {
+    return getOS() == Triple::Hurd;
+  }
+
   /// Tests whether the OS uses glibc.
   bool isOSGlibc() const {
-    return (getOS() == Triple::Linux || getOS() == Triple::KFreeBSD) &&
+    return (getOS() == Triple::Linux || getOS() == Triple::KFreeBSD ||
+            getOS() == Triple::Hurd) &&
            !isAndroid();
   }
 
Index: llvm-toolchain-7-7.0.1~+rc2/lib/Support/Triple.cpp
===================================================================
--- llvm-toolchain-7-7.0.1~+rc2.orig/lib/Support/Triple.cpp
+++ llvm-toolchain-7-7.0.1~+rc2/lib/Support/Triple.cpp
@@ -209,6 +209,7 @@ StringRef Triple::getOSTypeName(OSType K
   case Mesa3D: return "mesa3d";
   case Contiki: return "contiki";
   case AMDPAL: return "amdpal";
+  case Hurd: return "hurd";
   }
 
   llvm_unreachable("Invalid OSType");
@@ -502,6 +503,7 @@ static Triple::OSType parseOS(StringRef
     .StartsWith("mesa3d", Triple::Mesa3D)
     .StartsWith("contiki", Triple::Contiki)
     .StartsWith("amdpal", Triple::AMDPAL)
+    .StartsWith("hurd", Triple::Hurd)
     .Default(Triple::UnknownOS);
 }
 
Index: llvm/unittests/ADT/TripleTest.cpp
===================================================================
--- llvm/unittests/ADT/TripleTest.cpp	(révision 346226)
+++ llvm/unittests/ADT/TripleTest.cpp	(copie de travail)
@@ -93,6 +93,12 @@
   EXPECT_EQ(Triple::Contiki, T.getOS());
   EXPECT_EQ(Triple::UnknownEnvironment, T.getEnvironment());
 
+  T = Triple("i386-pc-hurd-gnu");
+  EXPECT_EQ(Triple::x86, T.getArch());
+  EXPECT_EQ(Triple::PC, T.getVendor());
+  EXPECT_EQ(Triple::Hurd, T.getOS());
+  EXPECT_EQ(Triple::GNU, T.getEnvironment());
+
   T = Triple("x86_64-pc-linux-gnu");
   EXPECT_EQ(Triple::x86_64, T.getArch());
   EXPECT_EQ(Triple::PC, T.getVendor());