util,tests: Added compiler test script

This script runs a series of compilations on gem5. The following
compilers are tested:

clang-9
clang-8
clang-7
clang-6
clang-5
clang-4
clang-3.9
gcc-9
gcc-8
gcc-7
gcc-6
gcc-5
gcc-4.8 (to be dropped soon:
         https://gem5.atlassian.net/browse/GEM5-218)

They are tested by building the following build targets:

ARM
ARM_MESI_Three_Level
Garnet_standalone
GCN3_X86
MIPS
NULL_MESI_Two_Level
NULL_MOESI_CMP_directory
NULL_MOESI_CMP_token
NULL_MOESI_hammer
POWER
RISCV
SPARC
X86
X86_MOESI_AMD_BASE

For each, ".opt" and ".fast" compiler build settings are tested.

clang-9 and gcc-9 are tested against all targets with each build
setting. For the remaining compilers, a random build target is
chosen. After the script has run, the output of the tests can be
found in "compile-test-out".

Docker is required to run this script.

Change-Id: Id3bf4c89b9d424c87e9409930ee2aceaef72cb29
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/30395
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>

util/compiler-tests.sh

@@ -0,0 +1,132 @@
+#!/bin/bash
+
+# This script will run all our supported compilers (see the "images" set)
+# against gem5. The "ubuntu-20.04_all-dependencies" and "clang-version-9"
+# images are run against all built targets. The remainder are evaluated
+# against a random shuffling of built targets.
+
+dir="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null 2>&1 && pwd )"
+gem5_root="${dir}/.."
+build_dir="${gem5_root}/build"
+num_cores=`nproc`
+
+# All Docker images in the gem5 testing GCR which we want to compile with.
+images=("ubuntu-20.04_all-dependencies" # Uses GCC-9
+        "clang-version-9"
+        "gcc-version-8"
+        "gcc-version-7"
+        "gcc-version-6"
+        "gcc-version-5"
+        "gcc-version-4.8"
+        "clang-version-8"
+        "clang-version-7"
+        "clang-version-6.0"
+        "clang-version-5.0"
+        "clang-version-4.0"
+        "clang-version-3.9" )
+
+# A subset of the above list: these images will build against every target,
+# ignoring builds_per_compiler.
+comprehensive=("ubuntu-20.04_all-dependencies"
+               "clang-version-9")
+
+# All build targets in build_opt/ which we want to build using each image.
+builds=("ARM"
+        "ARM_MESI_Three_Level"
+        "Garnet_standalone"
+        "GCN3_X86"
+        "MIPS"
+        "NULL_MESI_Two_Level"
+        "NULL_MOESI_CMP_directory"
+        "NULL_MOESI_CMP_token"
+        "NULL_MOESI_hammer"
+        "POWER"
+        "RISCV"
+        "SPARC"
+        "X86"
+        "X86_MOESI_AMD_Base")
+
+# The optimizations to use for each build target.
+opts=(".opt"
+      ".fast")
+
+# The number of build targets to randomly pull from the build target list for
+# each compiler. To perform a full comprehensive test which covers every
+# possible pair of compiler and build target, set builds_per_compiler equal to
+# the expression ${#builds[@]}.
+builds_per_compiler=1
+
+# Base URL of the gem5 testing images.
+base_url="gcr.io/gem5-test"
+
+# Arguments passed into scons on every build target test.
+build_args="-j ${num_cores}"
+
+# Testing directory variables
+mkdir -p "${build_dir}" # Create the build directory if it doesn't exist.
+test_dir_final="${gem5_root}/compile-test-out"
+test_dir="${gem5_root}/.compile-test-out"
+exits="${test_dir}/exit-codes.csv"
+
+# Create the testing output directory and files
+rm -rf $test_dir_final
+rm -rf $test_dir
+mkdir $test_dir
+touch $exits
+echo "compiler,build_target,exit_code" >> $exits
+
+for compiler in ${images[@]}; do
+    echo "Starting build tests with '$compiler'..."
+    # Generate a randomized list of build targets
+    build_permutation=($(shuf -i 0-$((${#builds[@]} - 1)) ))
+
+    builds_count=$builds_per_compiler
+    if [[ " ${comprehensive[@]} " =~ " $compiler " ]]; then
+        echo "'$compiler' was found in the comprehensive tests. All ISAs will be built."
+        builds_count=${#builds[@]}
+    fi
+
+    # Slice the first $builds_count entries of the permutation to get our
+    # targets for this test
+    build_indices=(${build_permutation[@]:0:$builds_count})
+
+    repo_name="${base_url}/${compiler}:latest"
+
+    # Grab compiler image
+    docker pull $repo_name >/dev/null
+
+    mkdir "$test_dir/$compiler"
+
+    for build_index in ${build_indices[@]}; do
+        for build_opt in ${opts[@]}; do
+            build="${builds[$build_index]}"
+            build_out="build/$build/gem5$build_opt"
+            build_stdout="$test_dir/$compiler/$build$build_opt.stdout"
+            build_stderr="$test_dir/$compiler/$build$build_opt.stderr"
+
+            # Clean the build
+            rm -rf "${build_dir}"
+
+            touch $build_stdout
+            touch $build_stderr
+
+            echo "  * Building target '$build$build_opt' with '$compiler'..."
+
+            # Build with container
+            {
+                docker run --rm -v ${gem5_root}:/gem5 -u $UID:$GID -w /gem5 \
+                    $repo_name scons $build_out $build_args
+            }>$build_stdout 2>$build_stderr
+            result=$?
+
+            echo "$compiler,$build/gem5$build_opt,$result" >> $exits
+            if [ $result -ne 0 ]; then
+                echo "  ! Failed with exit code $result."
+            else
+                echo "    Done."
+            fi
+        done
+    done
+done
+
+mv "${test_dir}" "${test_dir_final}"