[cmake] Add an option to build llvm with IR PGO

vedantk · vedantk · commit 9aaaeb3c93c6 · 2017-09-20T17:16:01.000Z
This adds an LLVM_ENABLE_IR_PGO option to enable building llvm and its tools with IR PGO instrumentation. Usage: -DLLVM_BUILD_INSTRUMENTED=On -DLLVM_ENABLE_IR_PGO=On (both options must be enabled) Differential Revision: https://reviews.llvm.org/D38066 llvm-svn: 313770
diff --git a/llvm/CMakeLists.txt b/llvm/CMakeLists.txt
@@ -548,18 +548,18 @@ else()
   set(LLVM_ADD_NATIVE_VISUALIZERS_TO_SOLUTION FALSE CACHE INTERNAL "For Visual Studio 2013, manually copy natvis files to Documents\\Visual Studio 2013\\Visualizers" FORCE)
 endif()
 
-if (LLVM_BUILD_INSTRUMENTED OR LLVM_BUILD_INSTRUMENTED_COVERAGE)
+if (LLVM_BUILD_INSTRUMENTED OR LLVM_BUILD_INSTRUMENTED_COVERAGE OR
+    LLVM_ENABLE_IR_PGO)
   if(NOT LLVM_PROFILE_MERGE_POOL_SIZE)
     # A pool size of 1-2 is probably sufficient on a SSD. 3-4 should be fine
     # for spining disks. Anything higher may only help on slower mediums.
     set(LLVM_PROFILE_MERGE_POOL_SIZE "4")
   endif()
   if(NOT LLVM_PROFILE_FILE_PATTERN)
     if(NOT LLVM_PROFILE_DATA_DIR)
-      file(TO_NATIVE_PATH "${LLVM_BINARY_DIR}/profiles/%${LLVM_PROFILE_MERGE_POOL_SIZE}m.profraw" LLVM_PROFILE_FILE_PATTERN)
-    else()
-      file(TO_NATIVE_PATH "${LLVM_PROFILE_DATA_DIR}/%${LLVM_PROFILE_MERGE_POOL_SIZE}m.profraw" LLVM_PROFILE_FILE_PATTERN)
+      file(TO_NATIVE_PATH "${LLVM_BINARY_DIR}/profiles" LLVM_PROFILE_DATA_DIR)
     endif()
+		file(TO_NATIVE_PATH "${LLVM_PROFILE_DATA_DIR}/%${LLVM_PROFILE_MERGE_POOL_SIZE}m.profraw" LLVM_PROFILE_FILE_PATTERN)
   endif()
 endif()
 
diff --git a/llvm/cmake/modules/HandleLLVMOptions.cmake b/llvm/cmake/modules/HandleLLVMOptions.cmake
@@ -730,13 +730,27 @@ if(LLVM_ENABLE_EH AND NOT LLVM_ENABLE_RTTI)
   message(FATAL_ERROR "Exception handling requires RTTI. You must set LLVM_ENABLE_RTTI to ON")
 endif()
 
+option(LLVM_ENABLE_IR_PGO "Build LLVM and tools with IR PGO instrumentation (experimental)" Off)
+mark_as_advanced(LLVM_ENABLE_IR_PGO)
+
 option(LLVM_BUILD_INSTRUMENTED "Build LLVM and tools with PGO instrumentation" Off)
 mark_as_advanced(LLVM_BUILD_INSTRUMENTED)
-append_if(LLVM_BUILD_INSTRUMENTED "-fprofile-instr-generate='${LLVM_PROFILE_FILE_PATTERN}'"
-  CMAKE_CXX_FLAGS
-  CMAKE_C_FLAGS
-  CMAKE_EXE_LINKER_FLAGS
-  CMAKE_SHARED_LINKER_FLAGS)
+
+if (LLVM_BUILD_INSTRUMENTED)
+  if (LLVM_ENABLE_IR_PGO)
+    append("-fprofile-generate='${LLVM_PROFILE_DATA_DIR}'"
+      CMAKE_CXX_FLAGS
+      CMAKE_C_FLAGS
+      CMAKE_EXE_LINKER_FLAGS
+      CMAKE_SHARED_LINKER_FLAGS)
+  else()
+    append("-fprofile-instr-generate='${LLVM_PROFILE_FILE_PATTERN}'"
+      CMAKE_CXX_FLAGS
+      CMAKE_C_FLAGS
+      CMAKE_EXE_LINKER_FLAGS
+      CMAKE_SHARED_LINKER_FLAGS)
+  endif()
+endif()
 
 option(LLVM_BUILD_INSTRUMENTED_COVERAGE "Build LLVM and tools with Code Coverage instrumentation" Off)
 mark_as_advanced(LLVM_BUILD_INSTRUMENTED_COVERAGE)
