Subzero: Remove a couple clumsy uses of snprintf.

src/IceTimerTree.cpp

Index: src/IceTimerTree.cpp
diff --git a/src/IceTimerTree.cpp b/src/IceTimerTree.cpp
index 6cba289b1400aa6b3b53ebd1e7d2e2affe628d9c..ccc7788c254c093e7dbd50c15f670e94b33a93b8 100644
--- a/src/IceTimerTree.cpp
+++ b/src/IceTimerTree.cpp
@@ -22,6 +22,7 @@
 #pragma clang diagnostic ignored "-Wunused-parameter"
 #endif // __clang__
 
+#include "llvm/Support/Format.h"
 #include "llvm/Support/Timer.h"
 
 #ifdef __clang__
@@ -231,10 +232,8 @@ void dumpHelper(Ostream &Str, const DumpMapType &Map, double TotalTime) {
   if (!BuildDefs::timers())
     return;
   for (auto &I : reverse_range(Map)) {
-    char buf[80];
-    snprintf(buf, llvm::array_lengthof(buf), "  %10.6f (%4.1f%%): ", I.first,
-             I.first * 100 / TotalTime);
-    Str << buf << I.second << "\n";
+    Str << llvm::format("  %10.6f (%4.1f%%): ", I.first,
+                        I.first * 100 / TotalTime) << I.second << "\n";
   }
 }