[Cmake] Add an option to build LLVM using the experimental new pass manager

Add LLVM_USE_NEWPM to build LLVM using the experimental new pass manager.

Differential Revision: http://reviews.llvm.org/D57068

llvm-svn: 353550

llvm/cmake/modules/HandleLLVMOptions.cmake

@@ -784,6 +784,16 @@ 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_USE_NEWPM "Build LLVM using the experimental new pass manager" Off)
+mark_as_advanced(LLVM_USE_NEWPM)
+if (LLVM_USE_NEWPM)
+  append("-fexperimental-new-pass-manager"
+    CMAKE_CXX_FLAGS
+    CMAKE_C_FLAGS
+    CMAKE_EXE_LINKER_FLAGS
+    CMAKE_SHARED_LINKER_FLAGS)
+endif()
+
 option(LLVM_ENABLE_IR_PGO "Build LLVM and tools with IR PGO instrumentation (deprecated)" Off)
 mark_as_advanced(LLVM_ENABLE_IR_PGO)
 

llvm/docs/CMake.rst

@@ -582,6 +582,9 @@ LLVM-specific variables
   If enabled, the compiler version check will only warn when using a toolchain
   which is about to be deprecated, instead of emitting an error.
 
+**LLVM_USE_NEWPM**:BOOL
+  If enabled, use the experimental new pass manager.
+
 CMake Caches
 ============