[cmake] Canonicalize CMake booleans to 0/1 for lit interop

Canonicalize all CMake booleans to 0/1 before passing them to lit, to
ensure that the Python side handles all of them consistently
and correctly. 0/1 is a safe choice of values that trigger the same
boolean interpretation in CMake, Python and C++.

Furthermore, using them without quotes improves the chance Python will
explicitly fail when an incorrect value (such as ON/OFF, TRUE/FALSE,
YES/NO) is accidentally passed, rather than silently misinterpreting
the value.

This replaces a lot of different logics spread around lit site files,
attempting to partially reproduce the boolean logic used in CMake
and usually silently failing when an uncommon value was used instead.
In fact, some of them were never working correctly since different
values were assigned in CMake and checked in Python.

The alternative solution could be to create a common parser for CMake
booleans in lit and use it consistently throughout the site files.
However, it does not seem like the best idea to create redundant
implementation of the same logic and have to follow upstream if it ever
is extended to handle more values.

Differential Revision: https://reviews.llvm.org/D28294

llvm-svn: 291284

2 files changed, 13 insertions, 7 deletions

diff --git a/llvm/cmake/config-ix.cmake b/llvm/cmake/config-ix.cmake
index d76f1293d02..0f1fc34ed28 100755
--- a/llvm/cmake/config-ix.cmake
+++ b/llvm/cmake/config-ix.cmake
@@ -462,13 +462,6 @@ if( MSVC )
   if(LLVM_ENABLE_DIA_SDK AND NOT HAVE_DIA_SDK)
     message(FATAL_ERROR "DIA SDK not found. If you have both VS 2012 and 2013 installed, you may need to uninstall the former and re-install the latter afterwards.")
   endif()
-
-  # Normalize to 0/1 for lit.site.cfg
-  if(LLVM_ENABLE_DIA_SDK)
-    set(LLVM_ENABLE_DIA_SDK 1)
-  else()
-    set(LLVM_ENABLE_DIA_SDK 0)
-  endif()
 else()
   set(LLVM_ENABLE_DIA_SDK 0)
 endif( MSVC )
diff --git a/llvm/cmake/modules/AddLLVM.cmake b/llvm/cmake/modules/AddLLVM.cmake
index fbef1d04eac..0eb16974517 100644
--- a/llvm/cmake/modules/AddLLVM.cmake
+++ b/llvm/cmake/modules/AddLLVM.cmake
@@ -1067,6 +1067,19 @@ function(llvm_add_go_executable binary pkgpath)
   endif()
 endfunction()
 
+# This function canonicalize the CMake variables passed by names
+# from CMake boolean to 0/1 suitable for passing into Python or C++,
+# in place.
+function(llvm_canonicalize_cmake_booleans)
+  foreach(var ${ARGN})
+    if(${var})
+      set(${var} 1 PARENT_SCOPE)
+    else()
+      set(${var} 0 PARENT_SCOPE)
+    endif()
+  endforeach()
+endfunction(llvm_canonicalize_cmake_booleans)
+
 # This function provides an automatic way to 'configure'-like generate a file
 # based on a set of common and custom variables, specifically targeting the
 # variables needed for the 'lit.site.cfg' files. This function bundles the