Depend on Boost using FetchContent instead of relying on system-provi…

…ded Boost.

CMakeLists.txt

@@ -152,10 +152,6 @@ if(STATIC_BUILD_WITH_DYNAMIC_GLIBC OR STATIC_BUILD_WITH_DYNAMIC_STDLIB)
   endif()
   set(BUILD_SHARED_LIBS OFF)
   set(CMAKE_FIND_LIBRARY_SUFFIXES .a)
-  # Link Boost statically
-  # See https://cmake.org/cmake/help/latest/module/FindBoost.html for details
-  set(Boost_USE_STATIC_LIBS ON)
-  set(Boost_USE_STATIC_RUNTIME OFF)
   # Set the static variable
   set(P4C_STATIC_BUILD STATIC)
   # TODO: We can not use -static here because of compilation and portability problems:
@@ -203,6 +199,8 @@ include(Abseil)
 p4c_obtain_abseil()
 include(Protobuf)
 p4c_obtain_protobuf()
+include(Boost)
+p4c_obtain_boost()
 
 # We require -pthread to make std::call_once work, even if we're not using threads...
 set(THREADS_PREFER_PTHREAD_FLAG ON)
@@ -227,15 +225,14 @@ if (ENABLE_MULTITHREAD)
   add_definitions(-DMULTITHREAD)
 endif()
 list (APPEND P4C_LIB_DEPS ${CMAKE_THREAD_LIBS_INIT})
-include_directories(SYSTEM ${Boost_INCLUDE_DIRS})
-include_directories(SYSTEM ${PROTOBUF_INCLUDE_DIRS})
-set (HAVE_LIBBOOST_IOSTREAMS 1)
-list (APPEND P4C_LIB_DEPS ${Boost_LIBRARIES})
+include_directories(BEFORE SYSTEM ${Boost_INCLUDE_DIRS})
+include_directories(BEFORE SYSTEM ${PROTOBUF_INCLUDE_DIRS})
 if (ENABLE_GC)
   list (APPEND P4C_LIB_DEPS ${LIBGC_LIBRARIES})
 endif ()
 set (P4C_ABSL_LIBRARIES absl::flat_hash_map absl::flat_hash_set)
 list (APPEND P4C_LIB_DEPS ${P4C_ABSL_LIBRARIES})
+list(APPEND P4C_LIB_DEPS Boost::iostreams Boost::format Boost::multiprecision)
 
 # Other required libraries.
 p4c_add_library (rt clock_gettime HAVE_CLOCK_GETTIME)
@@ -468,7 +465,7 @@ endif ()
 if (ENABLE_EBPF)
     add_subdirectory (backends/ebpf)
 endif ()
-if (ENABLE_P4C_GRAPHS AND HAVE_LIBBOOST_GRAPH EQUAL 1)
+if (ENABLE_P4C_GRAPHS)
   add_subdirectory (backends/graphs)
 endif ()
 if (ENABLE_P4TC)

backends/graphs/CMakeLists.txt

@@ -12,6 +12,18 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+# fetchcontent_declare(
+#     boost_graph
+#     GIT_REPOSITORY https://github.com/boostorg/graph.git
+#     GIT_TAG boost-${P4C_BOOST_VERSION}
+#     USES_TERMINAL_DOWNLOAD TRUE
+#     GIT_PROGRESS TRUE
+#     GIT_SHALLOW TRUE
+# )
+# include_directories(BEFORE SYSTEM ${boost_graph_SOURCE_DIR}/include)
+# fetchcontent_makeavailable(boost_graph)
+
+
 configure_file("${CMAKE_CURRENT_SOURCE_DIR}/version.h.cmake"
   "${CMAKE_CURRENT_BINARY_DIR}/version.h" @ONLY)
 

backends/p4tools/common/lib/symbolic_env.cpp

@@ -3,8 +3,6 @@
 #include <algorithm>
 #include <utility>
 
-#include <boost/container/vector.hpp>
-
 #include "backends/p4tools/common/lib/model.h"
 #include "ir/indexed_vector.h"
 #include "ir/vector.h"

cmake/Boost.cmake

@@ -0,0 +1,76 @@
+macro(p4c_obtain_boost)
+  option(
+    P4C_USE_PREINSTALLED_BOOST
+    "Look for a preinstalled version of Boost in the system instead of installing the library using FetchContent."
+    OFF
+  )
+
+  set(P4C_BOOST_VERSION "1.85.0")
+
+  # If P4C_USE_PREINSTALLED_BOOST is ON just try to find a preinstalled version of Boost.
+  if(P4C_USE_PREINSTALLED_BOOST)
+    if(NOT BUILD_SHARED_LIBS)
+      # Link Boost statically
+      # See https://cmake.org/cmake/help/latest/module/FindBoost.html for details
+      set(Boost_USE_STATIC_LIBS ON)
+      set(Boost_USE_STATIC_RUNTIME OFF)
+    endif()
+
+    # The boost graph headers are optional and only required by the graphs back end.
+    find_package (Boost QUIET COMPONENTS graph)
+    if (Boost_FOUND)
+      set (HAVE_LIBBOOST_GRAPH 1)
+    else ()
+      message (WARNING "Boost graph headers not found, will not build 'graphs' backend")
+    endif ()
+    find_package (Boost REQUIRED COMPONENTS format multiprecision)
+    include_directories(SYSTEM ${Boost_INCLUDE_DIRS})
+
+  else()
+    message(STATUS "Fetching Boost version ${P4C_BOOST_VERSION} for P4C...")
+    # Print out download state while setting up Boost.
+    set(FETCHCONTENT_QUIET_PREV ${FETCHCONTENT_QUIET})
+    set(FETCHCONTENT_QUIET OFF)
+    # Unity builds do not work for Abseil...
+    set(CMAKE_UNITY_BUILD_PREV ${CMAKE_UNITY_BUILD})
+    set(CMAKE_UNITY_BUILD OFF)
+
+
+    # Add boost library sources.
+    set(BOOST_INCLUDE_LIBRARIES graph format multiprecision iostreams)
+    set(BOOST_ENABLE_CMAKE ON)
+
+    if (ENABLE_P4C_GRAPHS)
+      set(HAVE_LIBBOOST_GRAPH 1)
+    endif()
+
+    # Always link Boost statically.
+    set(Boost_USE_STATIC_LIBS ON)
+    set(Boost_USE_STATIC_RUNTIME OFF)
+    set(BOOST_MP_STANDALONE ON CACHE BOOL "Use Boost.Multiprecision in standalone mode")
+
+    # Download and extract the boost library from GitHub.
+    message(STATUS "Downloading and extracting boost library sources. This may take some time...")
+    FetchContent_Declare(
+        Boost
+        URL https://github.com/boostorg/boost/releases/download/boost-${P4C_BOOST_VERSION}/boost-${P4C_BOOST_VERSION}-cmake.7z
+        USES_TERMINAL_DOWNLOAD TRUE
+        GIT_PROGRESS TRUE
+        DOWNLOAD_NO_EXTRACT FALSE
+    )
+    FetchContent_MakeAvailable(Boost)
+    include_directories(BEFORE SYSTEM ${Boost_SOURCE_DIR}/libs/iostreams/include)
+    include_directories(BEFORE SYSTEM ${Boost_SOURCE_DIR}/libs/format/include)
+    include_directories(BEFORE SYSTEM ${Boost_SOURCE_DIR}/libs/multiprecision/include)
+    include_directories(BEFORE SYSTEM ${Boost_SOURCE_DIR}/libs/graph/include)
+
+
+    # Reset temporary variable modifications.
+    set(CMAKE_UNITY_BUILD ${CMAKE_UNITY_BUILD_PREV})
+    set(FETCHCONTENT_QUIET ${FETCHCONTENT_QUIET_PREV})
+  endif()
+
+  set (HAVE_LIBBOOST_IOSTREAMS TRUE)
+
+  message(STATUS "Done with setting up Boost for P4C.")
+endmacro(p4c_obtain_boost)

ir/solver.h

@@ -4,9 +4,8 @@
 #include <optional>
 #include <vector>
 
-#include <boost/container/flat_map.hpp>
-#include <boost/container/flat_set.hpp>
-
+#include "absl/container/flat_hash_map.h"
+#include "absl/container/flat_hash_set.h"
 #include "ir/ir.h"
 #include "lib/castable.h"
 #include "lib/cstring.h"
@@ -20,13 +19,16 @@ struct SymbolicVarComp {
     bool operator()(const IR::SymbolicVariable *s1, const IR::SymbolicVariable *s2) const {
         return s1->operator<(*s2);
     }
+    size_t operator()(const IR::SymbolicVariable *s1) const {
+        return std::hash<cstring>()(s1->label);
+    }
 };
 
 /// This type maps symbolic variables to their value assigned by the solver.
-using SymbolicMapping = boost::container::flat_map<const IR::SymbolicVariable *,
-                                                   const IR::Expression *, SymbolicVarComp>;
+using SymbolicMapping =
+    absl::flat_hash_map<const IR::SymbolicVariable *, const IR::Expression *, SymbolicVarComp>;
 
-using SymbolicSet = boost::container::flat_set<const IR::SymbolicVariable *, SymbolicVarComp>;
+using SymbolicSet = absl::flat_hash_set<const IR::SymbolicVariable *, SymbolicVarComp>;
 
 /// Provides a higher-level interface for an SMT solver.
 class AbstractSolver : public ICastable {

tools/ci-build.sh

@@ -71,9 +71,6 @@ P4C_DEPS="bison \
           g++ \
           git \
           lld \
-          libboost-dev \
-          libboost-graph-dev \
-          libboost-iostreams-dev \
           libfl-dev \
           pkg-config \
           python3 \

tools/install_mac_deps.sh

@@ -37,21 +37,14 @@ HOMEBREW_PREFIX=$(brew --prefix)
 # Fetch the latest formulae
 brew update
 
-BOOST_LIB="[email protected]"
 REQUIRED_PACKAGES=(
     autoconf automake ccache cmake libtool
     openssl pkg-config coreutils bison grep ninja
-    ${BOOST_LIB}
 )
 for package in "${REQUIRED_PACKAGES[@]}"; do
   brew_install ${package}
 done
 
-# Check if linking is needed.
-if ! brew ls --linked --formula ${BOOST_LIB} > /dev/null 2>&1; then
-  brew link ${BOOST_LIB}
-fi
-
 # Check if PATH modification is needed.
 if ! grep -q "$(brew --prefix bison)/bin" ~/.bash_profile; then
   echo 'export PATH="$(brew --prefix bison)/bin:$PATH"' >> ~/.bash_profile