WIP: Refactor CMake build system to more modular

Author: markos

CMakeLists.txt

@@ -29,22 +29,6 @@ matching of regular expressions across streams of data.
 
 Vectorscan is typically used in a DPI library stack, just like Hyperscan.
 
-# Cross Compiling for AArch64
-
-- To cross compile for AArch64, first adjust the variables set in cmake/setenv-arm64-cross.sh.
-  - `export CROSS=<arm-cross-compiler-dir>/bin/aarch64-linux-gnu-`
-  - `export CROSS_SYS=<arm-cross-compiler-system-dir>`
-  - `export BOOST_PATH=<boost-source-dir>`
-- Set the environment variables:
-  - `source cmake/setenv-arm64-cross.sh`
-- Configure Vectorscan:
-  - `mkdir <build-dir-name>`
-  - `cd <build-dir>`
-  - `cmake -DCROSS_COMPILE_AARCH64=1 <hyperscan-source-dir> -DCMAKE_TOOLCHAIN_FILE=<hyperscan-source-dir>/cmake/arm64-cross.cmake`
-- Build Vectorscan:
-  - `make -jT` where T is the number of threads used to compile.
-  - `cmake --build . -- -j T` can also be used instead of make.
-
 # Compiling for SVE
 
 The following cmake variables can be set in order to target Arm's Scalable

README.md

@@ -0,0 +1,130 @@
+if (NOT FAT_RUNTIME)
+    if (BUILD_SVE2_BITPERM)
+        message (STATUS "SVE2_BITPERM implies SVE2, enabling BUILD_SVE2")
+        set(BUILD_SVE2 ON)
+    endif ()
+    if (BUILD_SVE2)
+        message (STATUS "SVE2 implies SVE, enabling BUILD_SVE")
+        set(BUILD_SVE ON)
+    endif ()
+endif ()
+
+if (ARCH_AARCH64)
+    if (NOT FAT_RUNTIME)
+        if (BUILD_SVE2_BITPERM AND NOT SVE2_BITPERM_FOUND)
+            set(GNUCC_ARCH "${GNUCC_ARCH}+sve2-bitperm")
+        elseif (BUILD_SVE2 AND NOT SVE2_FOUND)
+            set(GNUCC_ARCH "${GNUCC_ARCH}+sve2")
+        elseif (BUILD_SVE AND NOT SVE_FOUND)
+            set(GNUCC_ARCH "${GNUCC_ARCH}+sve")
+        endif ()
+    else()
+        set(ARCH_C_FLAGS "")
+        set(ARCH_CXX_FLAGS "")
+    endif()
+endif(ARCH_AARCH64)
+
+CHECK_INCLUDE_FILE_CXX(arm_neon.h HAVE_C_ARM_NEON_H)
+if (BUILD_SVE OR BUILD_SVE2 OR BUILD_SVE2_BITPERM OR FAT_RUNTIME)
+  if (CMAKE_COMPILER_IS_CLANG)
+    set(CMAKE_REQUIRED_FLAGS "-${ARCH_FLAG}=armv8-a+sve")
+  else()
+    set(CMAKE_REQUIRED_FLAGS ${ARCH_CXX_FLAGS})
+  endif()
+  CHECK_INCLUDE_FILE_CXX(arm_sve.h HAVE_C_ARM_SVE_H)
+  if (NOT HAVE_C_ARM_SVE_H)
+    message(FATAL_ERROR "arm_sve.h is required to build for SVE.")
+  endif()
+endif()
+
+if (HAVE_C_EC_H)
+    set (INTRIN_INC_H "altivec.h")
+else()
+    message (FATAL_ERROR "No intrinsics header found for VSX")
+endif ()
+
+if (ARCH_ARM32 OR ARCH_AARCH64)
+    CHECK_C_SOURCE_COMPILES("#include <${INTRIN_INC_H}>
+int main() {
+    int32x4_t a = vdupq_n_s32(1);
+    (void)a;
+}" HAVE_NEON)
+endif ()
+
+set(PREV_FLAGS "${CMAKE_C_FLAGS}")
+if (BUILD_SVE2_BITPERM)
+    set(CMAKE_C_FLAGS "-march=${GNUCC_ARCH} ${CMAKE_C_FLAGS}")
+    CHECK_C_SOURCE_COMPILES("#include <arm_sve.h>
+    int main() {
+        svuint8_t a = svbext(svdup_u8(1), svdup_u8(2));
+        (void)a;
+    }" HAVE_SVE2_BITPERM)
+	if (HAVE_SVE2_BITPERM AND NOT FAT_RUNTIME)
+            add_definitions(-DHAVE_SVE2_BITPERM)
+        endif ()
+    endif()
+    if (BUILD_SVE2)
+        set(CMAKE_C_FLAGS "-march=${GNUCC_ARCH} ${CMAKE_C_FLAGS}")
+        CHECK_C_SOURCE_COMPILES("#include <arm_sve.h>
+        int main() {
+            svuint8_t a = svbsl(svdup_u8(1), svdup_u8(2), svdup_u8(3));
+            (void)a;
+        }" HAVE_SVE2)
+    endif()
+    if ((HAVE_SVE2 OR HAVE_SVE2_BITPERM) AND NOT FAT_RUNTIME)
+        add_definitions(-DHAVE_SVE2)
+    endif ()
+    if (BUILD_SVE)
+        set(CMAKE_C_FLAGS "-march=${GNUCC_ARCH} ${CMAKE_C_FLAGS}")
+        CHECK_C_SOURCE_COMPILES("#include <arm_sve.h>
+        int main() {
+            svuint8_t a = svdup_u8(1);
+            (void)a;
+        }" HAVE_SVE)
+    endif ()
+    if ((HAVE_SVE OR HAVE_SVE2 OR HAVE_SVE2_BITPERM) AND NOT FAT_RUNTIME)
+        add_definitions(-DHAVE_SVE)
+    endif ()
+    set(CMAKE_C_FLAGS "${PREV_FLAGS}")
+endif()
+
+if (FAT_RUNTIME)
+    if ((ARCH_IA32 OR ARCH_X86_64) AND NOT HAVE_SSE42)
+        message(FATAL_ERROR "SSE4.2 support required to build fat runtime")
+    endif ()
+    if ((ARCH_IA32 OR ARCH_X86_64) AND BUILD_AVX2 AND NOT HAVE_AVX2)
+        message(FATAL_ERROR "AVX2 support required to build fat runtime")
+    endif ()
+    if ((ARCH_IA32 OR ARCH_X86_64) AND BUILD_AVX512 AND NOT HAVE_AVX512)
+        message(FATAL_ERROR "AVX512 support requested but not supported")
+    endif ()
+    if ((ARCH_IA32 OR ARCH_X86_64) AND BUILD_AVX512VBMI AND NOT HAVE_AVX512VBMI)
+        message(FATAL_ERROR "AVX512VBMI support requested but not supported")
+    endif ()
+else (NOT FAT_RUNTIME)
+    if (ARCH_AARCH64 AND NOT BUILD_SVE)
+        message(STATUS "Building without SVE support")
+    endif ()
+    if (ARCH_AARCH64 AND NOT BUILD_SVE2)
+        message(STATUS "Building without SVE2 support")
+    endif ()
+    if ((ARCH_ARM32 OR ARCH_AARCH64) AND NOT HAVE_NEON)
+        message(FATAL_ERROR "Neon/ASIMD support required for Arm support")
+    endif ()
+endif ()
+
+    string(FIND "${GNUCC_ARCH}" "sve" POS_SVE)
+    string(FIND "${GNUCC_ARCH}" "sve2" POS_SVE2)
+    string(FIND "${GNUCC_ARCH}" "sve2-bitperm" POS_SVE2_BITPERM)
+    if(NOT POS_SVE2_BITPERM EQUAL 0)
+        set(SVE2_BITPERM_FOUND 1)
+        set(SVE2_FOUND 1)
+        set(SVE_FOUND 1)
+    elseif(NOT POS_SVE2 EQUAL 0)
+        set(SVE2_FOUND 1)
+        set(SVE_FOUND 1)
+    elseif (NOT POS_SVE EQUAL 0)
+        set(SVE_FOUND 1)
+        set(SVE2_BITPERM_FOUND 1)
+    endif()
+