Created Ice::Instrumentation base class and accompanying hooks.

src/IceCfg.cpp

Index: src/IceCfg.cpp
diff --git a/src/IceCfg.cpp b/src/IceCfg.cpp
index 8f6a2fffaca0ecbf8d040b895458c0b33bb69895..c7840363ee09e4db09ffa00c71e088ffaf76a308 100644
--- a/src/IceCfg.cpp
+++ b/src/IceCfg.cpp
@@ -22,6 +22,7 @@
 #include "IceELFObjectWriter.h"
 #include "IceGlobalInits.h"
 #include "IceInst.h"
+#include "IceInstrumentation.h"
 #include "IceInstVarIter.h"
 #include "IceLiveness.h"
 #include "IceLoopAnalyzer.h"
@@ -238,6 +239,10 @@ void Cfg::translate() {
     if (auto *Var64On32 = llvm::dyn_cast<Variable64On32>(Var))
       Var64On32->initHiLo(this);
 
+  // TODO(tlively): Never sanitize in the minimal build.

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

Conditionalize this on BuildDefs::minimal.

This code base prefers not to run unnecessary code in a minimal build. Hence,
replace with

   if (!BuildDefs.minimal()) {
     getContext() ...
     dump(...)
   }

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

Done.

+  getContext()->instrumentFunc(this);
+  dump("Instrumented CFG");
+
   // The set of translation passes and their order are determined by the
   // target.
   getTarget()->translate();