Created Ice::Instrumentation base class and accompanying hooks.

src/IceGlobalContext.cpp

Index: src/IceGlobalContext.cpp
diff --git a/src/IceGlobalContext.cpp b/src/IceGlobalContext.cpp
index 058825b79dc194647e46f2f937eb674b21d14ea7..4d485b3ec900ba660130ecdf495da10c7ac64bd2 100644
--- a/src/IceGlobalContext.cpp
+++ b/src/IceGlobalContext.cpp
@@ -486,6 +486,10 @@ void GlobalContext::lowerGlobals(const std::string &SectionSuffix) {
     RandomShuffle(Globals.begin(), Globals.end(),
                   [&RNG](int N) { return (uint32_t)RNG.next(N); });
   }
+
+  if (Instrumentor)

[Karl, 2016/06/06 22:27:02]

Again, enclose code inside a conditional on BuildDefs::minimal().

[tlively, 2016/06/07 00:43:05]

Done.

+    Instrumentor->instrumentGlobals();
+
   DataLowering->lowerGlobals(Globals, SectionSuffix);
   if (ProfileBlockInfos.empty() && DisposeGlobalVariablesAfterLowering) {
     Globals.clearAndPurge();