[cmake] Unbreak LLVM-Config.cmake / llvm_expand_dependencies.

The algorithm for sorting libraries in topological order, as
previously implemented, had a few issues:
  * It didn't make any sense.
  * It didn't actually sort libraries in topological order.
  * It hung on some inputs, e.g. "LLVMipo".

This commit replaces the old algorithm with a straightforward port
from llvm-config.cpp.

llvm-svn: 224554
This commit is contained in:
Peter Zotov 2014-12-18 23:56:52 +00:00
parent 824e011ad7
commit f94eed6083
1 changed files with 30 additions and 20 deletions

View File

@ -152,29 +152,39 @@ function(llvm_map_components_to_libnames out_libs)
set(${out_libs} ${expanded_components} PARENT_SCOPE)
endfunction()
# Perform a post-order traversal of the dependency graph.
# This duplicates the algorithm used by llvm-config, originally
# in tools/llvm-config/llvm-config.cpp, function ComputeLibsForComponents.
function(expand_topologically name required_libs visited_libs)
list(FIND visited_libs ${name} found)
if( found LESS 0 )
list(APPEND visited_libs ${name})
set(visited_libs ${visited_libs} PARENT_SCOPE)
get_property(lib_deps GLOBAL PROPERTY LLVMBUILD_LIB_DEPS_${name})
foreach( lib_dep ${lib_deps} )
expand_topologically(${lib_dep} "${required_libs}" "${visited_libs}")
set(required_libs ${required_libs} PARENT_SCOPE)
set(visited_libs ${visited_libs} PARENT_SCOPE)
endforeach()
list(APPEND required_libs ${name})
set(required_libs ${required_libs} PARENT_SCOPE)
endif()
endfunction()
# Expand dependencies while topologically sorting the list of libraries:
function(llvm_expand_dependencies out_libs)
set(expanded_components ${ARGN})
list(LENGTH expanded_components lst_size)
set(cursor 0)
set(processed)
while( cursor LESS lst_size )
list(GET expanded_components ${cursor} lib)
get_property(lib_deps GLOBAL PROPERTY LLVMBUILD_LIB_DEPS_${lib})
list(APPEND expanded_components ${lib_deps})
# Remove duplicates at the front:
list(REVERSE expanded_components)
list(REMOVE_DUPLICATES expanded_components)
list(REVERSE expanded_components)
list(APPEND processed ${lib})
# Find the maximum index that doesn't have to be re-processed:
while(NOT "${expanded_components}" MATCHES "^${processed}.*" )
list(REMOVE_AT processed -1)
endwhile()
list(LENGTH processed cursor)
list(LENGTH expanded_components lst_size)
endwhile( cursor LESS lst_size )
set(${out_libs} ${expanded_components} PARENT_SCOPE)
set(required_libs)
set(visited_libs)
foreach( lib ${expanded_components} )
expand_topologically(${lib} "${required_libs}" "${visited_libs}")
endforeach()
list(REVERSE required_libs)
set(${out_libs} ${required_libs} PARENT_SCOPE)
endfunction()
function(explicit_map_components_to_libraries out_libs)