[tools] Only build lldb-instr and lldb-vscode if asked.

[davide]

Summary

Saves some build times, and they're not part of the usual
developer workflow.

[JDevlieghere]

We need to define these variables in the cache and make sure the test suite knows about them.

For lldb-instr for example, which lives in lit/tools/lldb-instr, you'd have to configure lit.site.cfg.py.in to know about wheter it's enabled or not (for example config.have_lldb_instr) and then check for this configuration variable in the lit.site.cfg in the lldb-instr test dir.

[davide]

OK, on it.

[labath]

LLDB_TOOL_$TOOL_BUILD would be a better name for consistency with llvm. In fact, if we started using the llvm cmake macros like add_llvm_subdirectory, it would handle this automatically, including creating the cache variable.

The only difference would be that the variable would default to "On", whereas you seem to want default-off. (I'm a bit torn on whether this is good. On one hand, I understand the desire to not build this stuff, but on the other, this creates an inconsistency with llvm, which builds everything by default, and consistency is a good thing.)

Also, I'd like to nominate lldb-mi as an additional optional feature. :)

[JDevlieghere]

In D60780#1468927, @labath wrote:

LLDB_TOOL_$TOOL_BUILD would be a better name for consistency with llvm. In fact, if we started using the llvm cmake macros like add_llvm_subdirectory, it would handle this automatically, including creating the cache variable.

The only difference would be that the variable would default to "On", whereas you seem to want default-off. (I'm a bit torn on whether this is good. On one hand, I understand the desire to not build this stuff, but on the other, this creates an inconsistency with llvm, which builds everything by default, and consistency is a good thing.)

Also, I'd like to nominate lldb-mi as an additional optional feature. :)

+1 on everything Pavel said. I'd also prefer to keep this on by default.

[davide]

updated.

[JDevlieghere]

lldb/cmake/modules/AddLLDB.cmake

145 ↗

(On Diff #195443)

Let's drop optional from the name

lldb/lit/lit.site.cfg.py.in

21 ↗

(On Diff #195443)

You can use llvm_canonicalize_cmake_booleans to make it a real boolean similar to config.have_zlib

Also, maybe use "have" instead of "has" for consistency?

[davide]

Jonas' comments

[JDevlieghere]

Thanks!

cmake/modules/AddLLDB.cmake

if(ARG_GENERATE_INSTALL)
     if (NOT CMAKE_CONFIGURATION_TYPES)
       add_llvm_install_targets(install-${name}
                                DEPENDS ${name}
                                COMPONENT ${name})
     endif()
   endif()
 endfunction(add_lldb_executable)
 
+
+macro(add_lldb_tool_subdirectory name)
+  add_llvm_subdirectory(LLDB TOOL ${name})
+endmacro()
+
 function(add_lldb_tool name)
   add_lldb_executable(${name} GENERATE_INSTALL ${ARGN})
 endfunction()
 
 # Support appending linker flags to an existing target.
 # This will preserve the existing linker flags on the
 # target, if there are any.
 function(lldb_append_link_flags target_name new_link_flags)

lit/CMakeLists.txt

 
 if(TARGET lld)
   list(APPEND LLDB_TEST_DEPS lld)
 endif()
 
 # the value is not canonicalized within LLVM
 llvm_canonicalize_cmake_booleans(
   LLDB_DISABLE_PYTHON
+  LLDB_TOOL_LLDB_INSTR_BUILD
+  LLDB_TOOL_LLDB_VSCODE_BUILD
   LLVM_ENABLE_ZLIB
   LLDB_IS_64_BITS)
 
 configure_lit_site_cfg(
   ${CMAKE_CURRENT_SOURCE_DIR}/lit.site.cfg.py.in
   ${CMAKE_CURRENT_BINARY_DIR}/lit.site.cfg.py
   MAIN_CONFIG
   ${CMAKE_CURRENT_SOURCE_DIR}/lit.cfg.py)

lit/lit.site.cfg.py.in

 # should not need to be escaped.
 config.lldb_lit_tools_dir = r"@LLDB_LIT_TOOLS_DIR@"
 config.target_triple = "@TARGET_TRIPLE@"
 config.python_executable = "@PYTHON_EXECUTABLE@"
 config.have_zlib = @LLVM_ENABLE_ZLIB@
 config.host_triple = "@LLVM_HOST_TRIPLE@"
 config.lldb_bitness = 64 if @LLDB_IS_64_BITS@ else 32
 config.lldb_disable_python = @LLDB_DISABLE_PYTHON@
+config.have_lldb_instr = @LLDB_TOOL_LLDB_INSTR_BUILD@
+config.have_lldb_vscode = @LLDB_TOOL_LLDB_VSCODE_BUILD@
 config.maxIndividualTestTime = 600
 
 # Support substitution of the tools and libs dirs with user parameters. This is
 # used when we can't determine the tool dir at configuration time.
 try:
     config.llvm_tools_dir = config.llvm_tools_dir % lit_config.params
     config.llvm_libs_dir = config.llvm_libs_dir % lit_config.params
     config.llvm_shlib_dir = config.llvm_shlib_dir % lit_config.params

lit/tools/lldb-instr/lit.local.cfg

+import sys
+  
+if not config.have_lldb_instr:
+    config.unsupported = True

tools/CMakeLists.txt

 add_subdirectory(argdumper)
 add_subdirectory(driver)
 add_subdirectory(intel-features)
-add_subdirectory(lldb-instr)
 add_subdirectory(lldb-mi)
 add_subdirectory(lldb-test)
-add_subdirectory(lldb-vscode)
+
+add_lldb_tool_subdirectory(lldb-instr)
+add_lldb_tool_subdirectory(lldb-vscode)
 
 if (CMAKE_SYSTEM_NAME MATCHES "Darwin")
   add_subdirectory(darwin-debug)
   add_subdirectory(debugserver)
 endif()
 
 if (LLDB_CAN_USE_LLDB_SERVER AND NOT SKIP_LLDB_SERVER_BUILD)
   add_subdirectory(lldb-server)
 endif()