Expose a TargetMachine::getTargetTransformInfo function

Summary:
This makes the TargetMachine interface a bit simpler.  We still need
the std::function in TargetIRAnalysis to avoid having to add a
dependency from Analysis to Target.

See discussion:
http://lists.llvm.org/pipermail/llvm-dev/2017-December/119749.html

I avoided adding all of the backend owners to this review since the
change is simple, but let me know if you feel differently about this.

Reviewers: echristo, MatzeB, hfinkel

Reviewed By: hfinkel

Subscribers: jholewinski, jfb, arsenm, dschuff, mcrosier, sdardis, nemanjai, nhaehnle, javed.absar, sbc100, jgravelle-google, aheejin, kbarton, llvm-commits

Differential Revision: https://reviews.llvm.org/D41464

llvm-svn: 321234
diff --git a/llvm/lib/Target/ARC/ARCTargetMachine.cpp b/llvm/lib/Target/ARC/ARCTargetMachine.cpp
index d2512c2..1acae3a 100644
--- a/llvm/lib/Target/ARC/ARCTargetMachine.cpp
+++ b/llvm/lib/Target/ARC/ARCTargetMachine.cpp
@@ -88,8 +88,7 @@
   RegisterTargetMachine<ARCTargetMachine> X(getTheARCTarget());
 }
 
-TargetIRAnalysis ARCTargetMachine::getTargetIRAnalysis() {
-  return TargetIRAnalysis([this](const Function &F) {
-    return TargetTransformInfo(ARCTTIImpl(this, F));
-  });
+TargetTransformInfo
+ARCTargetMachine::getTargetTransformInfo(const Function &F) {
+  return TargetTransformInfo(ARCTTIImpl(this, F));
 }