Add instructions for setting paths for HPVM installation

README.md

@@ -22,7 +22,7 @@ HPVM is currently at version 0.5. For more about what HPVM is, see [our website]
 The following components are required to be installed on your machine to build HPVM.
 
 * GCC (>=5.1.0)
-* CMake (>=3.4.3)
+* CMake (>=3.17.0)
 * Python (>=2.7)
 * GNU Make (>=3.79.1)
 * OpenCL (>=1.0.0) or CUDA (>=9.1, only required for GPU support)
@@ -49,6 +49,12 @@ git clone https://gitlab.engr.illinois.edu/llvm/hpvm-release.git/
 cd hpvm-release/hpvm
 ```
 
+Before installing HPVM, some paths must be set for installation to succeed. The following variables in set_paths.sh must be set:
+
+* CUDA_TOOLKIT_PATH --- Path to the CUDA toolkit
+* CUDA_INCLUDE_PATH --- Path to the CUDA headers
+* CUDA_LIB_PATH -- Path to CUDA libraries 
+
 HPVM installer script can be used to download, configure and build HPVM along with LLVM and Clang. 
 ```shell
 bash install.sh