Moving CGF::EmitAlignmentAssumption to IRBuilder

The functionality contained in CodeGenFunction::EmitAlignmentAssumption has
been moved to IRBuilder (so that it can also be used by LLVM-level code).
Remove this now-duplicate implementation in favor of the IRBuilder code.

llvm-svn: 219877
diff --git a/clang/lib/CodeGen/CodeGenFunction.h b/clang/lib/CodeGen/CodeGenFunction.h
index 865f1c9..09b1271 100644
--- a/clang/lib/CodeGen/CodeGenFunction.h
+++ b/clang/lib/CodeGen/CodeGenFunction.h
@@ -1807,7 +1807,10 @@
                                          bool isInc, bool isPre);
 
   void EmitAlignmentAssumption(llvm::Value *PtrValue, unsigned Alignment,
-                               llvm::Value *OffsetValue = nullptr);
+                               llvm::Value *OffsetValue = nullptr) {
+    Builder.CreateAlignmentAssumption(CGM.getDataLayout(), PtrValue, Alignment,
+                                      OffsetValue);
+  }
 
   //===--------------------------------------------------------------------===//
   //                            Declaration Emission