1#!/bin/bash
2
3# llvm now lives in a mono-repo along with clang, libc, lldb and a whole bunch
4# of other projects (~90k files at time of writing).
5# SwiftShader only requires the llvm project from this repo, and does not wish
6# to pull in everything else.
7# This script performs the following:
8# * The llvm10-clean branch is fetched and checked out.
9# * A sparse checkout of the llvm project is made to a temporary directory.
10# * The third_party/llvm-10.0/llvm is replaced with the latest LLVM version.
11# * This is committed and pushed.
12# * The original branch is checked out again, and a merge from llvm10-clean to
13#   the original branch is made.
14
15THIRD_PARTY_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}")" >/dev/null 2>&1 && pwd )"
16STAGING_DIR="/tmp/llvm-10-update"
17CLEAN_BRANCH="llvm10-clean"
18SOURCE_DIR="${STAGING_DIR}/llvm"
19TARGET_DIR="${THIRD_PARTY_DIR}/llvm-10.0/llvm"
20LLVM_REPO_BRANCH="release/10.x"
21BUG_NUMBER="b/152339534"
22
23SWIFTSHADER_HEAD=`git rev-parse HEAD`
24
25# Check there are no local changes
26if ! git diff --quiet HEAD; then
27  echo "Git workspace not clean"
28  exit 1
29fi
30
31# Clone or update the staging directory
32if [[ -d "$STAGING_DIR" ]]; then
33  pushd "$STAGING_DIR"
34else
35  mkdir "$STAGING_DIR"
36  pushd "$STAGING_DIR"
37  git init
38  git remote add origin https://github.com/llvm/llvm-project.git
39  git config core.sparsecheckout true
40  echo "/llvm/lib" >> .git/info/sparse-checkout
41  echo "/llvm/include" >> .git/info/sparse-checkout
42fi
43git pull origin $LLVM_REPO_BRANCH
44LLVM_HEAD=`git log HEAD -n 1 --pretty=format:'%h'`
45popd
46
47if [[ -d "$TARGET_DIR" ]]; then
48  # Look for the last update change.
49  LAST_TARGET_UPDATE=`git log --grep="^llvm-10-update: [0-9a-f]\{9\}$" -n 1 --pretty=format:'%h' ${TARGET_DIR}`
50  if [[ ! -z "$LAST_TARGET_UPDATE" ]]; then
51    # Get the LLVM commit hash from the update change.
52    LAST_SOURCE_UPDATE=`git log $LAST_TARGET_UPDATE -n 1 | grep -oP "llvm-10-update: \K([0-9a-f]{9})"`
53    if [ $LLVM_HEAD == $LAST_SOURCE_UPDATE ]; then
54      echo "No new LLVM changes to apply"
55      exit 0
56    fi
57
58    # Gather list of changes since last update
59    pushd "$STAGING_DIR"
60    LLVM_CHANGE_LOG=`git log $LAST_SOURCE_UPDATE..$LLVM_HEAD --pretty=format:'  %h %s'`
61    LLVM_CHANGE_LOG="Changes:\n${LLVM_CHANGE_LOG}\n\n"
62    popd
63  fi
64fi
65
66COMMIT_MSG=`echo -e "Update LLVM 10 to ${LLVM_HEAD}\n\n${LLVM_CHANGE_LOG}Commands:\n  third_party/update-llvm-10.sh\n\nllvm-10-update: ${LLVM_HEAD}\nBug: ${BUG_NUMBER}"`
67
68# Switch to the llvm-10-clean branch.
69git fetch "https://swiftshader.googlesource.com/SwiftShader" $CLEAN_BRANCH
70git checkout FETCH_HEAD
71
72# Delete the target directory. We're going to re-populate it.
73rm -fr "$TARGET_DIR"
74
75# Update SwiftShader's $TARGET_DIR with a clean copy of latest LLVM
76mkdir -p "$TARGET_DIR"
77cp -r "$SOURCE_DIR/." "$TARGET_DIR"
78git add "$TARGET_DIR"
79git commit -m "$COMMIT_MSG"
80MERGE_SOURCE=`git log HEAD -n 1 --pretty=format:'%h'`
81
82# Push llvm-10-clean branch.
83git push "https://swiftshader.googlesource.com/SwiftShader" $CLEAN_BRANCH
84
85# Switch to the branch in use when calling the script.
86git checkout $SWIFTSHADER_HEAD
87
88# Update SwiftShader's $TARGET_DIR with a clean copy of latest LLVM
89git merge -m "$COMMIT_MSG" "$MERGE_SOURCE"
90
91# We're now done with the staging dir. Delete it.
92rm -fr "$STAGING_DIR"
93