From 9a5cd969bb16b2b74437040a736d07b28cdbde94 Mon Sep 17 00:00:00 2001
From: Andreas Beckmann <anbe@debian.org>
Date: Mon, 14 Aug 2023 14:53:17 +0100
Subject: [PATCH] add support for a GENERIC cpu type that uses llvm defaults

Forwarded: not-needed


Gbp-Pq: Name generic-cpu.patch
---
 cmake/LLVM.cmake               | 12 ++++++++++--
 lib/CL/devices/common.c        |  3 +++
 lib/CL/pocl_llvm_build.cc      |  3 +--
 lib/kernel/host/CMakeLists.txt |  5 +++++
 4 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/cmake/LLVM.cmake b/cmake/LLVM.cmake
index eef1039..e0260ae 100644
--- a/cmake/LLVM.cmake
+++ b/cmake/LLVM.cmake
@@ -695,17 +695,25 @@ endif()
 # Some architectures have -march and -mcpu reversed
 if(NOT DEFINED CLANG_MARCH_FLAG)
   message(STATUS "Checking clang -march vs. -mcpu flag")
-  custom_try_compile_clang_silent("" "return 0;" RES ${CLANG_TARGET_OPTION}${LLC_TRIPLE} -march=${SELECTED_HOST_CPU})
+ if(LLC_HOST_CPU STREQUAL "GENERIC" AND NOT KERNELLIB_HOST_CPU_VARIANTS STREQUAL "distro")
+  set(CLANG_MARCH_FLAG "-None=")
+ else()
+  set(LLC_HOST_CPU_TEST "${SELECTED_HOST_CPU}")
+  if(LLC_HOST_CPU STREQUAL "GENERIC")
+    set(LLC_HOST_CPU_TEST "${LLC_HOST_CPU_AUTO}")
+  endif()
+  custom_try_compile_clang_silent("" "return 0;" RES ${CLANG_TARGET_OPTION}${LLC_TRIPLE} -march=${LLC_HOST_CPU_TEST})
   if(NOT RES)
     set(CLANG_MARCH_FLAG "-march=")
   else()
-    custom_try_compile_clang_silent("" "return 0;" RES ${CLANG_TARGET_OPTION}${LLC_TRIPLE} -mcpu=${SELECTED_HOST_CPU})
+    custom_try_compile_clang_silent("" "return 0;" RES ${CLANG_TARGET_OPTION}${LLC_TRIPLE} -mcpu=${LLC_HOST_CPU_TEST})
     if(NOT RES)
       set(CLANG_MARCH_FLAG "-mcpu=")
     else()
       message(FATAL_ERROR "Could not determine whether to use -march or -mcpu with clang")
     endif()
   endif()
+ endif()
   message(STATUS "  Using ${CLANG_MARCH_FLAG}")
 
   set(CLANG_MARCH_FLAG ${CLANG_MARCH_FLAG} CACHE INTERNAL "Clang option used to specify the target cpu")
diff --git a/lib/CL/devices/common.c b/lib/CL/devices/common.c
index 01803a5..ac8f923 100644
--- a/lib/CL/devices/common.c
+++ b/lib/CL/devices/common.c
@@ -1673,6 +1673,9 @@ pocl_init_default_device_infos (cl_device_id dev)
   dev->llvm_cpu = pocl_get_llvm_cpu_name ();
 #endif
 
+  if(dev->llvm_cpu && (!strcmp(dev->llvm_cpu, "GENERIC")))
+    dev->llvm_cpu = NULL;
+
 #else /* No compiler, no CPU info */
   dev->kernellib_name = NULL;
   dev->llvm_cpu = NULL;
diff --git a/lib/CL/pocl_llvm_build.cc b/lib/CL/pocl_llvm_build.cc
index 59e5780..302bfef 100644
--- a/lib/CL/pocl_llvm_build.cc
+++ b/lib/CL/pocl_llvm_build.cc
@@ -1012,8 +1012,7 @@ static llvm::Module *getKernelLibrary(cl_device_id device,
     kernellib_fallback = kernellib;
     kernellib_fallback += OCL_KERNEL_TARGET_CPU;
     kernellib_fallback += ".bc";
-    if (device->llvm_cpu)
-      kernellib += device->llvm_cpu;
+    kernellib += device->llvm_cpu ? device->llvm_cpu : "GENERIC";
 #endif
   }
   kernellib += ".bc";
diff --git a/lib/kernel/host/CMakeLists.txt b/lib/kernel/host/CMakeLists.txt
index 6caef5a..c5bbfc1 100644
--- a/lib/kernel/host/CMakeLists.txt
+++ b/lib/kernel/host/CMakeLists.txt
@@ -571,6 +571,11 @@ else()
   set(LLC_CPUFLAGS "-mcpu=${VARIANT}")
 endif()
 
+if("${VARIANT}" STREQUAL "GENERIC")
+  set(CLANG_CPUFLAGS "")
+  set(LLC_CPUFLAGS "")
+endif()
+
 separate_arguments(CLANG_CPUFLAGS)
 separate_arguments(LLC_CPUFLAGS)
 set(CLANG_FLAGS ${HOST_CLANG_FLAGS} ${CLANG_CPUFLAGS}
-- 
2.30.2