[SYCL] clean build directory if build scripts are changed

Signed-off-by: Vladimir Lazarev <[email protected]>

Author: vladimirlaz

buildbot/dependency.sh

@@ -1,8 +1,10 @@
-#!/bin/bash
+#!/bin/bash -x
 
 BRANCH=
 BUILD_NUMBER=
 PR_NUMBER=
+SRC_DIR="../llvm.src"
+DST_DIR="."
 
 # $1 exit code
 # $2 error message
@@ -15,17 +17,38 @@ exit_if_err()
 }
 
 unset OPTIND
-while getopts ":b:r:n:" option; do
+while getopts ":b:r:n:s:d" option; do
     case $option in
         b) BRANCH=$OPTARG ;;
         n) BUILD_NUMBER=$OPTARG ;;
+        s) SRC_DIR=$OPTARG ;;
+        d) DST_DIR=$OPTARG ;;
         r) PR_NUMBER=$OPTARG ;;
     esac
 done && shift $(($OPTIND - 1))
 
 # we're in llvm.obj dir
 BUILD_DIR=${PWD}
 
+# Get changed build script files
+cd ${SRC_DIR}
+git fetch -t origin refs/pull/${PR_NUMBER}/merge
+exit_if_err $? "fail to get tags"
+git checkout -B refs/pull/${PR_NUMBER}/merge
+exit_if_err $? "fail to get tags"
+base_commit=`git merge-base origin/sycl refs/pull/${PR_NUMBER}/merge`
+exit_if_err $? "fail to get base commit"
+
+BUILD_SCRIPT=`git --no-pager diff ${base_commit} refs/pull/${PR_NUMBER}/merge --name-only buildbot`
+cd -
+
+## Clean up build directory if build scripts has changed
+cd ${DST_DIR}
+if [  -n "$BUILD_SCRIPT" ]; then
+   rm -rf *
+fi
+cd -
+
 ## GET dependencies
 if [ ! -d "OpenCL-Headers" ]; then
     git clone https://github.com/KhronosGroup/OpenCL-Headers OpenCL-Headers