[unittests] Move TargetRegistry test from Support to MC

This removes the dependency from SupportTests to all of the LLVM
backends, and makes it link faster.

llvm-svn: 259705

1 files changed, 46 insertions, 0 deletions

diff --git a/llvm/unittests/MC/TargetRegistry.cpp b/llvm/unittests/MC/TargetRegistry.cpp
new file mode 100644
index 00000000000..eb46b22f06c
--- /dev/null
+++ b/llvm/unittests/MC/TargetRegistry.cpp
@@ -0,0 +1,46 @@
+//===- unittests/MC/TargetRegistry.cpp ------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// The target registry code lives in Support, but it relies on linking in all
+// LLVM targets. We keep this test with the MC tests, which already do that, to
+// keep the SupportTests target small.
+
+#include "llvm/Support/TargetRegistry.h"
+#include "llvm/Support/TargetSelect.h"
+#include "gtest/gtest.h"
+
+using namespace llvm;
+
+namespace {
+
+TEST(TargetRegistry, TargetHasArchType) {
+  // Presence of at least one target will be asserted when done with the loop,
+  // else this would pass by accident if InitializeAllTargetInfos were omitted.
+  int Count = 0;
+
+  llvm::InitializeAllTargetInfos();
+
+  for (const Target &T : TargetRegistry::targets()) {
+    StringRef Name = T.getName();
+    // There is really no way (at present) to ask a Target whether it targets
+    // a specific architecture, because the logic for that is buried in a
+    // predicate.
+    // We can't ask the predicate "Are you a function that always returns
+    // false?"
+    // So given that the cpp backend truly has no target arch, it is skipped.
+    if (Name != "cpp") {
+      Triple::ArchType Arch = Triple::getArchTypeForLLVMName(Name);
+      EXPECT_NE(Arch, Triple::UnknownArch);
+      ++Count;
+    }
+  }
+  ASSERT_NE(Count, 0);
+}
+
+} // end namespace