Enable linking tools, shared libraries against libLLVM

Summary:
Three closely related changes, to have a mode in which we link all
executables and shared libraries against libLLVM. 

1. Add a new LLVM_LINK_LLVM_DYLIB cmake option, which, when ON, will link
   executables and shared libraries against libLLVM. For this to work, it
   is necessary to also set LLVM_BUILD_LLVM_DYLIB and LLVM_DYLIB_EXPORT_ALL.

   It is not strictly necessary to set LLVM_DISABLE_LLVM_DYLIB_ATEXIT, but
   we also default to OFF in this mode, or tools tend to misbehave (e.g.
   stdout may not flush on exit when output is buffered.)

   llvm-config and Tablegen do not use libLLVM, as they are dependencies of
   libLLVM.

2. Modify llvm-go to take a new flag, "linkmode=component-libs|dylib".
   Depending on which one is passed (default is component-libs), we link
   with the individual libraries or libLLVM respectively. We pass in dylib
   when LLVM_LINK_LLVM_DYLIB is ON.

3. Fix LLVM_DYLIB_EXPORT_ALL on Linux, and expand the symbols exported to
   actually export all. Don't strip leading underscore from symbols on Linux,
   and make sure we get all exported symbols and weak-with-default symbols
   ("W" in nm output). Without these changes, passes won't load because
   the "Annotate..." symbols defined in lib/Support/Valigrind.cpp are not
   found.

Testing:
 - Ran default build ("ninja") with LLVM, clang, compiler-rt, llgo, lldb.
 - Ran "check", "check-clang", "check-tsan", "check-libgo" targets. I've
   never had much success with LLDB tests, and llgoi is currently broken
   so check-llgo fails for an unrelated reason.
 - Ran "lldb" to ensure it loads.

Reviewers: chandlerc, beanz, pcc, rnk

Subscribers: rnk, chapuni, sylvestre.ledru, llvm-commits

Differential Revision: http://reviews.llvm.org/D12488

llvm-svn: 246527

2 files changed, 33 insertions, 10 deletions

diff --git a/llvm/cmake/modules/AddLLVM.cmake b/llvm/cmake/modules/AddLLVM.cmake
index 30351ee92ad..f53b89d32ab 100644
--- a/llvm/cmake/modules/AddLLVM.cmake
+++ b/llvm/cmake/modules/AddLLVM.cmake
@@ -41,7 +41,7 @@ function(llvm_update_compile_flags name)
   # Assume that;
   #   - LLVM_COMPILE_FLAGS is list.
   #   - PROPERTY COMPILE_FLAGS is string.
-  string(REPLACE ";" " " target_compile_flags "${LLVM_COMPILE_FLAGS}")
+  string(REPLACE ";" " " target_compile_flags " ${LLVM_COMPILE_FLAGS}")
 
   if(update_src_props)
     foreach(fn ${sources})
@@ -303,6 +303,9 @@ endfunction(set_windows_version_resource_properties)
 #   MODULE
 #     Target ${name} might not be created on unsupported platforms.
 #     Check with "if(TARGET ${name})".
+#   DISABLE_LLVM_LINK_LLVM_DYLIB
+#     Do not link this library to libLLVM, even if
+#     LLVM_LINK_LLVM_DYLIB is enabled.
 #   OUTPUT_NAME name
 #     Corresponds to OUTPUT_NAME in target properties.
 #   DEPENDS targets...
@@ -316,7 +319,7 @@ endfunction(set_windows_version_resource_properties)
 #   )
 function(llvm_add_library name)
   cmake_parse_arguments(ARG
-    "MODULE;SHARED;STATIC"
+    "MODULE;SHARED;STATIC;DISABLE_LLVM_LINK_LLVM_DYLIB"
     "OUTPUT_NAME"
     "ADDITIONAL_HEADERS;DEPENDS;LINK_COMPONENTS;LINK_LIBS;OBJLIBS"
     ${ARGN})
@@ -444,10 +447,14 @@ function(llvm_add_library name)
   # property has been set to an empty value.
   get_property(lib_deps GLOBAL PROPERTY LLVMBUILD_LIB_DEPS_${name})
 
-  llvm_map_components_to_libnames(llvm_libs
-    ${ARG_LINK_COMPONENTS}
-    ${LLVM_LINK_COMPONENTS}
-    )
+  if (LLVM_LINK_LLVM_DYLIB AND NOT ARG_STATIC AND NOT ARG_DISABLE_LLVM_LINK_LLVM_DYLIB)
+    set(llvm_libs LLVM)
+  else()
+    llvm_map_components_to_libnames(llvm_libs
+      ${ARG_LINK_COMPONENTS}
+      ${LLVM_LINK_COMPONENTS}
+      )
+  endif()
 
   if(CMAKE_VERSION VERSION_LESS 2.8.12)
     # Link libs w/o keywords, assuming PUBLIC.
@@ -562,7 +569,8 @@ endmacro(add_llvm_loadable_module name)
 
 
 macro(add_llvm_executable name)
-  llvm_process_sources( ALL_FILES ${ARGN} )
+  cmake_parse_arguments(ARG "DISABLE_LLVM_LINK_LLVM_DYLIB" "" "" ${ARGN})
+  llvm_process_sources( ALL_FILES ${ARG_UNPARSED_ARGUMENTS} )
 
   # Generate objlib
   if(LLVM_ENABLE_OBJLIB)
@@ -604,7 +612,11 @@ macro(add_llvm_executable name)
 
   set(EXCLUDE_FROM_ALL OFF)
   set_output_directory(${name} ${LLVM_RUNTIME_OUTPUT_INTDIR} ${LLVM_LIBRARY_OUTPUT_INTDIR})
-  llvm_config( ${name} ${LLVM_LINK_COMPONENTS} )
+  if (LLVM_LINK_LLVM_DYLIB AND NOT ARG_DISABLE_LLVM_LINK_LLVM_DYLIB)
+    target_link_libraries(${name} LLVM)
+  else()
+    llvm_config( ${name} ${LLVM_LINK_COMPONENTS} )
+  endif()
   if( LLVM_COMMON_DEPENDS )
     add_dependencies( ${name} ${LLVM_COMMON_DEPENDS} )
   endif( LLVM_COMMON_DEPENDS )
@@ -836,8 +848,13 @@ function(llvm_add_go_executable binary pkgpath)
       set(cppflags "${cppflags} -I${d}")
     endforeach(d)
     set(ldflags "${CMAKE_EXE_LINKER_FLAGS}")
+    if (LLVM_LINK_LLVM_DYLIB)
+      set(linkmode "dylib")
+    else()
+      set(linkmode "component-libs")
+    endif()
     add_custom_command(OUTPUT ${binpath}
-      COMMAND ${CMAKE_BINARY_DIR}/bin/llvm-go "go=${GO_EXECUTABLE}" "cc=${cc}" "cxx=${cxx}" "cppflags=${cppflags}" "ldflags=${ldflags}"
+      COMMAND ${CMAKE_BINARY_DIR}/bin/llvm-go "go=${GO_EXECUTABLE}" "cc=${cc}" "cxx=${cxx}" "cppflags=${cppflags}" "ldflags=${ldflags}" "linkmode=${linkmode}"
               ${ARG_GOFLAGS} build -o ${binpath} ${pkgpath}
       DEPENDS llvm-config ${CMAKE_BINARY_DIR}/bin/llvm-go${CMAKE_EXECUTABLE_SUFFIX}
               ${llvmlibs} ${ARG_DEPENDS}
diff --git a/llvm/cmake/modules/TableGen.cmake b/llvm/cmake/modules/TableGen.cmake
index fcb445afc58..f1ddcd49a58 100644
--- a/llvm/cmake/modules/TableGen.cmake
+++ b/llvm/cmake/modules/TableGen.cmake
@@ -77,7 +77,13 @@ macro(add_tablegen target project)
   # FIXME: It leaks to user, callee of add_tablegen.
   set(LLVM_ENABLE_OBJLIB ON)
 
-  add_llvm_utility(${target} ${ARGN})
+  add_llvm_utility(
+    ${target} ${ARGN}
+    # libLLVM does not include the TableGen
+    # components, so we cannot link any tblgen
+    # utilities against it.
+    DISABLE_LLVM_LINK_LLVM_DYLIB)
+
   set(LLVM_LINK_COMPONENTS ${${target}_OLD_LLVM_LINK_COMPONENTS})
 
   set(${project}_TABLEGEN "${target}" CACHE