[llvm] r249911 - [CMake] Parallel make breaks on native tablegen

[Chris Bieneman via llvm-commits]

Author: cbieneman
Date: Fri Oct  9 17:26:04 2015
New Revision: 249911

URL: http://llvm.org/viewvc/llvm-project?rev=249911&view=rev
Log:
[CMake] Parallel make breaks on native tablegen

Patch by Alex Wang

This patch resolves a parallelization issue that occurs when native tablegen targets are built at the same time. They both try to build libSupport and clobber each other causing the builds to fail.

Modified:
    llvm/trunk/cmake/modules/TableGen.cmake

Modified: llvm/trunk/cmake/modules/TableGen.cmake
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/cmake/modules/TableGen.cmake?rev=249911&r1=249910&r2=249911&view=diff
==============================================================================
--- llvm/trunk/cmake/modules/TableGen.cmake (original)
+++ llvm/trunk/cmake/modules/TableGen.cmake Fri Oct  9 17:26:04 2015
@@ -70,6 +70,15 @@ function(add_public_tablegen_target targ
   set(LLVM_COMMON_DEPENDS ${LLVM_COMMON_DEPENDS} ${target} PARENT_SCOPE)
 endfunction()
 
+if(LLVM_USE_HOST_TOOLS)
+  add_custom_command(OUTPUT LIB_LLVMSUPPORT
+      COMMAND ${CMAKE_COMMAND} --build . --target LLVMSupport --config Release
+      DEPENDS CONFIGURE_LLVM_NATIVE
+      WORKING_DIRECTORY ${LLVM_NATIVE_BUILD}
+      COMMENT "Building libLLVMSupport for native TableGen...")
+  add_custom_target(NATIVE_LIB_LLVMSUPPORT DEPENDS LIB_LLVMSUPPORT)
+endif(LLVM_USE_HOST_TOOLS)
+
 macro(add_tablegen target project)
   set(${target}_OLD_LLVM_LINK_COMPONENTS ${LLVM_LINK_COMPONENTS})
   set(LLVM_LINK_COMPONENTS ${LLVM_LINK_COMPONENTS} TableGen)
@@ -109,7 +118,7 @@ macro(add_tablegen target project)
 
       add_custom_command(OUTPUT ${${project}_TABLEGEN_EXE}
         COMMAND ${CMAKE_COMMAND} --build . --target ${target} --config Release
-        DEPENDS CONFIGURE_LLVM_NATIVE ${target}
+        DEPENDS ${target} NATIVE_LIB_LLVMSUPPORT
         WORKING_DIRECTORY ${LLVM_NATIVE_BUILD}
         COMMENT "Building native TableGen...")
       add_custom_target(${project}-tablegen-host DEPENDS ${${project}_TABLEGEN_EXE})