diff --git a/HalideIR b/HalideIR
index f3eb854595ff99f4b05a5d8034bcacea30ef045b..cb3c025d5b91ab994b063a85bc935fc364d8f491 160000
--- a/HalideIR
+++ b/HalideIR
@@ -1 +1 @@
-Subproject commit f3eb854595ff99f4b05a5d8034bcacea30ef045b
+Subproject commit cb3c025d5b91ab994b063a85bc935fc364d8f491
diff --git a/README.md b/README.md
index 9f58baaaa926885c0ed8546eac251eea3e5dd123..07e550d7604368ade94eb7bb4f34cd602f2abca6 100644
--- a/README.md
+++ b/README.md
@@ -33,7 +33,6 @@ Acknowledgement
 ---------------
 We learnt a lot from the following projects when building TVM.
 - [Halide](https://github.com/halide/Halide): TVM uses [HalideIR](https://github.com/dmlc/HalideIR) as data structure for
-  arithematic simplification and low level lowering. HalideIR is derived from Halide.
-  We also learns from Halide when implementing the lowering pipeline in TVM.
+  arithematic simplification and low level lowering. We also learnt and adapted some part of lowering pipeline from Halide.
 - [Loopy](https://github.com/inducer/loopy): use of integer set analysis and its loop transformation primitives.
 - [Theano](https://github.com/Theano/Theano): the design inspiration of symbolic scan operator for recurrence.
diff --git a/src/codegen/llvm/codegen_llvm.cc b/src/codegen/llvm/codegen_llvm.cc
index 5af57b3f12fa460475b4e372ce6e2e28c3da5d50..941b045a026ae2af897b50611284825fdf764875 100644
--- a/src/codegen/llvm/codegen_llvm.cc
+++ b/src/codegen/llvm/codegen_llvm.cc
@@ -3,6 +3,7 @@
  * \file codegen_llvm.cc
  */
 #ifdef TVM_LLVM_VERSION
+// Part of the code are adapted from Halide's CodeGen_LLVM
 
 #include <tvm/runtime/device_api.h>
 #include <tvm/runtime/c_runtime_api.h>
@@ -492,6 +493,7 @@ llvm::Value* CodeGenLLVM::CreateBufferPtr(
   if (btype != ptype) {
     buffer = builder_->CreatePointerCast(buffer, ptype);
   }
+
   return builder_->CreateInBoundsGEP(buffer, index);
 }
 
diff --git a/src/pass/inject_prefetch.cc b/src/pass/inject_prefetch.cc
index 647db33457c264b31ec39209387ace6b1c816250..6d903292a004e141f1a9fbff314f8bd1aed1888c 100644
--- a/src/pass/inject_prefetch.cc
+++ b/src/pass/inject_prefetch.cc
@@ -2,6 +2,7 @@
  *  Copyright (c) 2017 by Contributors
  * \file inject_prefetch.cc
  */
+// Inject prefetch op in HalideIR
 #include <tvm/ir.h>
 #include <tvm/ir_mutator.h>
 #include <tvm/ir_visitor.h>
diff --git a/src/pass/storage_flatten.cc b/src/pass/storage_flatten.cc
index b7774c6225b88843387cd63cb2e5bea9070f9c9f..47d026f43538f898250b66c4305202ec0811e801 100644
--- a/src/pass/storage_flatten.cc
+++ b/src/pass/storage_flatten.cc
@@ -2,6 +2,8 @@
  *  Copyright (c) 2016 by Contributors
  * \file storage_flatten.cc
  */
+// Flattens storage from multi-dimensional array to 1D
+// buffer access as in Halide pipeline.
 #include <tvm/ir.h>
 #include <tvm/expr.h>
 #include <tvm/operation.h>
diff --git a/src/pass/unroll_loop.cc b/src/pass/unroll_loop.cc
index 8c4d9c1af7bf6f8d9d1939ea9e6faa3418b580f4..c9e5a47985c3b483a91419ce6014a18c4f712342 100644
--- a/src/pass/unroll_loop.cc
+++ b/src/pass/unroll_loop.cc
@@ -1,8 +1,9 @@
 /*!
  *  Copyright (c) 2017 by Contributors
- *  Loop unrolling.
+ *  Loop unrolling as in Halide pipeline.
  * \file unroll_loop.cc
  */
+// Unrolls the loop as in Halide pipeline.
 #include <tvm/ir.h>
 #include <tvm/ir_pass.h>
 #include <tvm/ir_mutator.h>
diff --git a/src/pass/vectorize_loop.cc b/src/pass/vectorize_loop.cc
index 1019d77d4c6c627b85fdcdd4ddad95c56da9c517..206b75ed068d2ba8e0b3af9064fc6c2d700cb4e5 100644
--- a/src/pass/vectorize_loop.cc
+++ b/src/pass/vectorize_loop.cc
@@ -1,8 +1,8 @@
 /*!
  *  Copyright (c) 2017 by Contributors
- *  Vectorize the loop
  * \file vectorize_loop.cc
  */
+// Loop vectorizer as in Halide pipeline.
 #include <tvm/ir.h>
 #include <tvm/ir_pass.h>
 #include <tvm/ir_mutator.h>