[libomptarget] Add AArch64 support

[pawosm01]

Summary

This adds AArch64 support to recently added part of the runtime responsible for offloading to target. This piece of code allows offloading-to-self on AArch64 machines.

[grokos]

LGTM. Thanks for submitting!

openmp/trunk/libomptarget/CMakeLists.txt

 
 # Message utilities.
 include(LibomptargetUtils)
 
 # Get dependencies for the different components of the project.
 include(LibomptargetGetDependencies)
 
 # This is a list of all the targets that are supported/tested right now.
+set (LIBOMPTARGET_ALL_TARGETS "${LIBOMPTARGET_ALL_TARGETS} aarch64-unknown-linux-gnu")
 set (LIBOMPTARGET_ALL_TARGETS "${LIBOMPTARGET_ALL_TARGETS} powerpc64le-ibm-linux-gnu")
 set (LIBOMPTARGET_ALL_TARGETS "${LIBOMPTARGET_ALL_TARGETS} powerpc64-ibm-linux-gnu")
 set (LIBOMPTARGET_ALL_TARGETS "${LIBOMPTARGET_ALL_TARGETS} x86_64-pc-linux-gnu")
 set (LIBOMPTARGET_ALL_TARGETS "${LIBOMPTARGET_ALL_TARGETS} nvptx64-nvidia-cuda")
 
 # Once the plugins for the different targets are validated, they will be added to
 # the list of supported targets in the current system.
 set (LIBOMPTARGET_SYSTEM_TARGETS "")

openmp/trunk/libomptarget/README.txt

 
 Architectures Supported
 =======================
 The current library has been only tested in Linux operating system and the 
 following host architectures: 
 * Intel(R) 64 architecture
 * IBM(R) Power architecture (big endian)
 * IBM(R) Power architecture (little endian)
+* ARM(R) AArch64 architecture (little endian)
 
 The currently supported offloading device architectures are:
 * Intel(R) 64 architecture (generic 64-bit plugin - mostly for testing purposes)
 * IBM(R) Power architecture (big endian) (generic 64-bit plugin - mostly for testing purposes)
 * IBM(R) Power architecture (little endian) (generic 64-bit plugin - mostly for testing purposes)
+* ARM(R) AArch64 architecture (little endian) (generic 64-bit plugin - mostly for testing purposes)
 * CUDA(R) enabled 64-bit NVIDIA(R) GPU architectures
 
 Supported RTL Build Configurations
 ==================================
 Supported Architectures: Intel(R) 64, IBM(R) Power 7 and Power 8
 
               ---------------------------
               |   gcc      |   clang    |

openmp/trunk/libomptarget/plugins/CMakeLists.txt

if(CMAKE_SYSTEM_PROCESSOR MATCHES "${tmachine}$")
   else(LIBOMPTARGET_DEP_LIBELF_FOUND)
     libomptarget_say("Not building ${tmachine_name} offloading plugin: libelf dependency not found.")
   endif(LIBOMPTARGET_DEP_LIBELF_FOUND)
 else()
   libomptarget_say("Not building ${tmachine_name} offloading plugin: machine not found in the system.")
 endif()
 endmacro()
 
+add_subdirectory(aarch64)
 add_subdirectory(cuda)
 add_subdirectory(ppc64)
 add_subdirectory(ppc64le)
 add_subdirectory(x86_64)
 
 # Make sure the parent scope can see the plugins that will be created.
 set(LIBOMPTARGET_SYSTEM_TARGETS "${LIBOMPTARGET_SYSTEM_TARGETS}" PARENT_SCOPE)
 

openmp/trunk/libomptarget/plugins/aarch64/CMakeLists.txt

+##===----------------------------------------------------------------------===##
+#
+#                     The LLVM Compiler Infrastructure
+#
+# This file is dual licensed under the MIT and the University of Illinois Open
+# Source Licenses. See LICENSE.txt for details.
+#
+##===----------------------------------------------------------------------===##
+#
+# Build a plugin for an aarch64 machine if available.
+#
+##===----------------------------------------------------------------------===##
+
+if(CMAKE_SYSTEM_NAME MATCHES "Linux")
+  build_generic_elf64("aarch64" "aarch64" "aarch64" "aarch64-unknown-linux-gnu" "183")
+else()
+ libomptarget_say("Not building aarch64 offloading plugin: machine not found in the system.")
+endif()

openmp/trunk/libomptarget/src/omptarget.cpp

 #define DP(...) DEBUGP("Libomptarget", __VA_ARGS__)
 #define INF_REF_CNT (LONG_MAX>>1) // leave room for additions/subtractions
 #define CONSIDERED_INF(x) (x > (INF_REF_CNT>>1))
 
 // List of all plugins that can support offloading.
 static const char *RTLNames[] = {
     /* PowerPC target */ "libomptarget.rtl.ppc64.so",
     /* x86_64 target  */ "libomptarget.rtl.x86_64.so",
-    /* CUDA target    */ "libomptarget.rtl.cuda.so"};
+    /* CUDA target    */ "libomptarget.rtl.cuda.so",
+    /* AArch64 target */ "libomptarget.rtl.aarch64.so"};
 
 // forward declarations
 struct RTLInfoTy;
 static int target(int32_t device_id, void *host_ptr, int32_t arg_num,
     void **args_base, void **args, int64_t *arg_sizes, int64_t *arg_types,
     int32_t team_num, int32_t thread_limit, int IsTeamConstruct);
 
 /// Map between host data and target data.

openmp/trunk/libomptarget/test/offloading/offloading_success.c

+// RUN: %libomptarget-compile-run-and-check-aarch64-unknown-linux-gnu
 // RUN: %libomptarget-compile-run-and-check-powerpc64-ibm-linux-gnu
 // RUN: %libomptarget-compile-run-and-check-powerpc64le-ibm-linux-gnu
 // RUN: %libomptarget-compile-run-and-check-x86_64-pc-linux-gnu
 
 #include <stdio.h>
 #include <omp.h>
 
 int main(void) {

openmp/trunk/libomptarget/test/offloading/offloading_success.cpp

+// RUN: %libomptarget-compilexx-run-and-check-aarch64-unknown-linux-gnu
 // RUN: %libomptarget-compilexx-run-and-check-powerpc64-ibm-linux-gnu
 // RUN: %libomptarget-compilexx-run-and-check-powerpc64le-ibm-linux-gnu
 // RUN: %libomptarget-compilexx-run-and-check-x86_64-pc-linux-gnu
 
 #include <stdio.h>
 #include <omp.h>
 
 int main(void) {