Implemented linking to a dummy ASan runtime

src/IceASanInstrumentation.cpp

Index: src/IceASanInstrumentation.cpp
diff --git a/src/IceASanInstrumentation.cpp b/src/IceASanInstrumentation.cpp
index 45ec038f4ed91c596e7a5f9a7ee242096441973f..36ffaae0543ec60356cd3421f150ec9dc547515d 100644
--- a/src/IceASanInstrumentation.cpp
+++ b/src/IceASanInstrumentation.cpp
@@ -15,7 +15,9 @@
 #include "IceASanInstrumentation.h"
 
 #include "IceBuildDefs.h"
+#include "IceCfgNode.h"
 #include "IceGlobalInits.h"
+#include "IceInst.h"
 
 #include <sstream>
 
@@ -109,4 +111,16 @@ ASanInstrumentation::createRz(VariableDeclarationList *List,
   return Rz;
 }
 
+void ASanInstrumentation::instrumentStart(Cfg *Func) {
+  Constant *ShadowMemInit =
+      Ctx->getConstantExternSym(Ctx->getGlobalString("__asan_init"));
+  constexpr SizeT NumArgs = 0;
+  constexpr Variable *Void = nullptr;
+  constexpr bool HasTailCall = false;

[Jim Stichnoth, 2016/06/15 00:19:35]

Newer code in Subzero uses a documentation idiom for these false constexprs:

  constexpr bool NoTailCall = false;
  ... InstCall::create(..., NoTailCall);

The initialization is a bit weird to read (double negative), but the create()
call is quite clear.

[tlively, 2016/06/15 16:32:00]

Done.

+
+  auto *Call =
+      InstCall::create(Func, NumArgs, Void, ShadowMemInit, HasTailCall);
+  Func->getEntryNode()->getInsts().push_front(Call);
+}
+
 } // end of namespace Ice