make all Emit*() functions consult the TargetLibraryInfo information before creating a call to a library function.
Update all clients to pass the TLI information around.
Previous draft reviewed by Eli.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160733 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/CodeGenPrepare.cpp b/lib/Transforms/Scalar/CodeGenPrepare.cpp
index 277c4d5..f425cd0 100644
--- a/lib/Transforms/Scalar/CodeGenPrepare.cpp
+++ b/lib/Transforms/Scalar/CodeGenPrepare.cpp
@@ -610,7 +610,7 @@
   // that have the default "don't know" as the objectsize.  Anything else
   // should be left alone.
   CodeGenPrepareFortifiedLibCalls Simplifier;
-  return Simplifier.fold(CI, TD);
+  return Simplifier.fold(CI, TD, TLInfo);
 }
 
 /// DupRetToEnableTailCallOpts - Look for opportunities to duplicate return