[Timers] TimerGroup: add constructor from StringMap<TimeRecord>

Summary:
This is needed for the continuation of D46504,
to be able to store the timings.

Reviewers: george.karpenkov, NoQ, alexfh, sbenza

Reviewed By: alexfh

Subscribers: llvm-commits, cfe-commits

Differential Revision: https://reviews.llvm.org/D46939

llvm-svn: 332506
diff --git a/llvm/lib/Support/Timer.cpp b/llvm/lib/Support/Timer.cpp
index fd587fb..61d3b6c 100644
--- a/llvm/lib/Support/Timer.cpp
+++ b/llvm/lib/Support/Timer.cpp
@@ -236,6 +236,15 @@
   TimerGroupList = this;
 }
 
+TimerGroup::TimerGroup(StringRef Name, StringRef Description,
+                       const StringMap<TimeRecord> &Records)
+    : TimerGroup(Name, Description) {
+  TimersToPrint.reserve(Records.size());
+  for (const auto &P : Records)
+    TimersToPrint.emplace_back(P.getValue(), P.getKey(), P.getKey());
+  assert(TimersToPrint.size() == Records.size() && "Size mismatch");
+}
+
 TimerGroup::~TimerGroup() {
   // If the timer group is destroyed before the timers it owns, accumulate and
   // print the timing data.