commit 2e2372117d35191a0e6c096c5f989930de6e12b1
author Lijian Zhang <Lijian.Zhang@arm.com> Mon Sep 10 17:13:56 2018 +0800
committer Damjan Marion <dmarion@me.com> Mon Oct 01 09:28:41 2018 +0000
tree 16ba106360c4bda39b78ee02f515cbbb2c284e0f
parent 88c6e0086b15963b4d1a268e1fe8bbc2bcd9779c

Support dynamic dual/quad loop selection on aarch64

Currently, there are three variants available on aarch64, qdf24xx, thunderx2t99, and cortex-a72.
-DCLIB_N_PREFETCHES is passed to source code to select dual/quad implementation.
Besides, different compiler options are applied on these critical functions.

gcc-7.3.0 reports ICE(internal compiler error) with -mtune=thunderx2t99,
so -mtune=thunderx2t99 is enabled only when gcc version is greater than 7.3.0

Cavium ThunderX2, Impermenter 0x43, Part 0x0af
    -march=armv8-a+crc+crypto -mtune=thunderx2t99
Qualcomm Centriq 2400, Impermenter 0x51, Part 0xc00
    -march=armv8.1-a+crc+crypto -mtune=qdf24xx
Cortex-A72, Impermenter 0x41, Part 0xd08
    -march=armv8-a+crc+crypto -mtune=cortex-a72

Change-Id: Id5649c6325c1e642d0fd42535e3908793b13e02a
Signed-off-by: Lijian Zhang <Lijian.Zhang@arm.com>
Reviewed-by: Sirshak Das <sirshak.das@arm.com>
Reviewed-by: Honnappa Nagarahalli <Honnappa.Nagarahalli@arm.com>

src/cmake/cpu.cmake

diff --git a/src/cmake/cpu.cmake b/src/cmake/cpu.cmake
index bdc9014..20dab7b 100644
--- a/src/cmake/cpu.cmake
+++ b/src/cmake/cpu.cmake
@@ -65,6 +65,22 @@
   endif()
 elseif(CMAKE_SYSTEM_PROCESSOR MATCHES "^(aarch64.*|AARCH64.*)")
   set(CMAKE_C_FLAGS "-march=armv8-a+crc ${CMAKE_C_FLAGS}")
+  check_c_compiler_flag("-march=armv8-a+crc+crypto -mtune=qdf24xx" compiler_flag_march_core_qdf24xx)
+  if(compiler_flag_march_core_qdf24xx)
+    list(APPEND MARCH_VARIANTS "qdf24xx\;-march=armv8-a+crc+crypto -DCLIB_N_PREFETCHES=8")
+  endif()
+  check_c_compiler_flag("-march=armv8.1-a+crc+crypto -mtune=thunderx2t99" compiler_flag_march_thunderx2t99)
+  if(compiler_flag_march_thunderx2t99)
+    if (CMAKE_C_COMPILER_VERSION VERSION_GREATER 7.3)
+      list(APPEND MARCH_VARIANTS "thunderx2t99\;-march=armv8.1-a+crc+crypto -mtune=thunderx2t99 -DCLIB_N_PREFETCHES=8")
+    else()
+      list(APPEND MARCH_VARIANTS "thunderx2t99\;-march=armv8.1-a+crc+crypto -DCLIB_N_PREFETCHES=8")
+    endif()
+  endif()
+  check_c_compiler_flag("-march=armv8-a+crc+crypto -mtune=cortex-a72" compiler_flag_march_cortexa72)
+  if(compiler_flag_march_cortexa72)
+    list(APPEND MARCH_VARIANTS "cortexa72\;-march=armv8-a+crc+crypto -mtune=cortex-a72 -DCLIB_N_PREFETCHES=6")
+  endif()
 endif()
 
 macro(vpp_library_set_multiarch_sources lib)