change the build command to remove the requirement of llvm-config pat…

…h, and support using CUDA_PATH from environment variable

CMakeLists.txt

@@ -4,13 +4,11 @@ project(CuPBoP)
 set(CMAKE_PROJECT_DESCRIPTION "Executing CUDA on non-NVIDIA architecture.")
 set(CMAKE_CXX_STANDARD "14")
 
-if(DEFINED LLVM_CONFIG_PATH)
-  if(EXISTS "${LLVM_CONFIG_PATH}")
-    set(LLVM_CONFIG "${LLVM_CONFIG_PATH}")
-  else()
-    message(FATAL_ERROR "llvm-config is not found in ${LLVM_CONFIG_PATH}")
-  endif()
-  message(STATUS "Using llvm-config: ${LLVM_CONFIG}")
+find_program(LLVM_CONFIG llvm-config)
+if(NOT LLVM_CONFIG)
+  message(FATAL_ERROR "llvm-config not found. Please install LLVM.")
+else()
+  message(STATUS "Found llvm-config: ${LLVM_CONFIG}")
   execute_process(
     COMMAND "${LLVM_CONFIG}" "--cxxflags"
     OUTPUT_VARIABLE LLVM_CXX_FLAG
@@ -23,14 +21,16 @@ if(DEFINED LLVM_CONFIG_PATH)
     COMMAND "${LLVM_CONFIG}" "--libs"
     OUTPUT_VARIABLE LLVM_LINK_FLAG
     OUTPUT_STRIP_TRAILING_WHITESPACE)
-else()
-  message(FATAL_ERROR "llvm-config is required")
 endif()
 
 if(DEFINED CUDA_PATH)
-  message(STATUS "Using CUDA: ${CUDA_PATH}")
+  message(STATUS "CUDA_PATH provided: ${CUDA_PATH}")
+elseif(DEFINED ENV{CUDA_PATH})
+  set(CUDA_PATH $ENV{CUDA_PATH})
+  message(STATUS "CUDA_PATH from environment: ${CUDA_PATH}")
 else()
-  message(FATAL_ERROR "CUDA_PATH is required")
+  message(FATAL_ERROR "CUDA_PATH is not provided. Please set CUDA_PATH or
+      define it as an environment variable.")
 endif()
 
 option(DEBUG "Print debug information." OFF)

README.md

@@ -37,9 +37,7 @@ For building CUDA toolkit, please refer to <https://developer.nvidia.com/cuda-do
    ```bash
    mkdir build && cd build
    #set -DDEBUG=ON for debugging
-   cmake .. \
-      -DLLVM_CONFIG_PATH=`which llvm-config` \
-      -DCUDA_PATH=$CUDA_PATH
+   cmake ..
    make
    ```