build: modify N_PREFETCH on Arm N2 to achieve best perf

[vpp.git] / src / cmake / cpu.cmake

diff --git a/src/cmake/cpu.cmake b/src/cmake/cpu.cmake
index c10158b..18a1210 100644 (file)
--- a/src/cmake/cpu.cmake
+++ b/src/cmake/cpu.cmake
@@ -59,13 +59,6 @@ endif()
 
 option(VPP_BUILD_NATIVE_ONLY "Build only for native CPU." OFF)
 
-if(VPP_BUILD_NATIVE_ONLY)
-  check_c_compiler_flag("-march=native" compiler_flag_march_native)
-  if(NOT compiler_flag_march_native)
-    message(FATAL_ERROR "Native-only build not supported by compiler")
-  endif()
-endif()
-
 macro(add_vpp_march_variant v)
   cmake_parse_arguments(ARG
     "OFF"
@@ -112,7 +105,14 @@ macro(add_vpp_march_variant v)
 endmacro()
 
 if(VPP_BUILD_NATIVE_ONLY)
-  set(VPP_DEFAULT_MARCH_FLAGS -march=native)
+  set(VPP_BUILD_NATIVE_ARCH "native" CACHE STRING "native CPU -march= value.")
+  set(VPP_DEFAULT_MARCH_FLAGS -march=${VPP_BUILD_NATIVE_ARCH})
+  if(VPP_BUILD_NATIVE_ONLY)
+    check_c_compiler_flag(${VPP_DEFAULT_MARCH_FLAGS} compiler_flag_march)
+    if(NOT compiler_flag_march)
+      message(FATAL_ERROR "Native-only build with ${VPP_DEFAULT_MARCH_FLAGS} is not supported by compiler")
+    endif()
+  endif()
   set(MARCH_VARIANTS_NAMES "native-only")
 elseif(CMAKE_SYSTEM_PROCESSOR MATCHES "amd64.*|x86_64.*|AMD64.*")
   set(VPP_DEFAULT_MARCH_FLAGS -march=corei7 -mtune=corei7-avx)
@@ -131,6 +131,16 @@ elseif(CMAKE_SYSTEM_PROCESSOR MATCHES "amd64.*|x86_64.*|AMD64.*")
     OFF
   )
 
+  add_vpp_march_variant(scalar
+    FLAGS -march=core2 -mno-mmx -mno-sse
+    OFF
+  )
+
+  add_vpp_march_variant(znver3
+    FLAGS -march=znver3 -mtune=znver3 -mprefer-vector-width=256
+    OFF
+  )
+
   if (GNU_ASSEMBLER_AVX512_BUG)
      message(WARNING "AVX-512 multiarch variant(s) disabled due to GNU Assembler bug")
   else()
@@ -146,6 +156,11 @@ elseif(CMAKE_SYSTEM_PROCESSOR MATCHES "amd64.*|x86_64.*|AMD64.*")
       FLAGS -march=sapphirerapids -mtune=sapphirerapids -mprefer-vector-width=512
       OFF
     )
+
+    add_vpp_march_variant(znver4
+      FLAGS -march=znver4 -mtune=znver4 -mprefer-vector-width=512
+      OFF
+    )
   endif()
 elseif(CMAKE_SYSTEM_PROCESSOR MATCHES "^(aarch64.*|AARCH64.*)")
   set(VPP_DEFAULT_MARCH_FLAGS -march=armv8-a+crc)
@@ -179,6 +194,12 @@ elseif(CMAKE_SYSTEM_PROCESSOR MATCHES "^(aarch64.*|AARCH64.*)")
     N_PREFETCHES 6
     CACHE_PREFETCH_BYTES 64
   )
+  add_vpp_march_variant(neoversen2
+    FLAGS -march=armv9-a+crypto -mtune=neoverse-n2
+    N_PREFETCHES 6
+    CACHE_PREFETCH_BYTES 64
+    OFF
+  )
 endif()
 
 macro(vpp_library_set_multiarch_sources lib)