Disable statistics on Release builds and move tests that depend on -stats.

Summary:
Statistics are still available in Release+Asserts (any +Asserts builds),
and stats can also be turned on with LLVM_ENABLE_STATS.

Move some of the FastISel stats that were moved under DEBUG()
back out of DEBUG(), since stats are disabled across the board now.

Many tests depend on grepping "-stats" output.  Move those into
a orig_dir/Stats/. so that they can be marked as unsupported
when building without statistics.

Differential Revision: http://llvm-reviews.chandlerc.com/D486

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176733 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Support/Statistic.cpp b/lib/Support/Statistic.cpp
index 3a65221..9c28176 100644
--- a/lib/Support/Statistic.cpp
+++ b/lib/Support/Statistic.cpp
@@ -40,7 +40,9 @@
 /// what they did.
 ///
 static cl::opt<bool>
-Enabled("stats", cl::desc("Enable statistics output from program"));
+Enabled(
+    "stats",
+    cl::desc("Enable statistics output from program (available with Asserts)"));
 
 
 namespace {
@@ -142,6 +144,7 @@
 }
 
 void llvm::PrintStatistics() {
+#if !defined(NDEBUG) || defined(LLVM_ENABLE_STATS)
   StatisticInfo &Stats = *StatInfo;
 
   // Statistics not enabled?
@@ -151,4 +154,17 @@
   raw_ostream &OutStream = *CreateInfoOutputFile();
   PrintStatistics(OutStream);
   delete &OutStream;   // Close the file.
+#else
+  // Check if the -stats option is set instead of checking
+  // !Stats.Stats.empty().  In release builds, Statistics operators
+  // do nothing, so stats are never Registered.
+  if (Enabled) {
+    // Get the stream to write to.
+    raw_ostream &OutStream = *CreateInfoOutputFile();
+    OutStream << "Statistics are disabled.  "
+            << "Build with asserts or with -DLLVM_ENABLE_STATS\n";
+    OutStream.flush();
+    delete &OutStream;   // Close the file.
+  }
+#endif
 }