Summary:
Cross-compilation uses recursive cmake invocations to build native host
tools. These recursive invocations only forward a fixed set of
variables/options, since the native environment is generally the default.
This change adds -DLLVM_TARGET_IS_CROSSCOMPILE_HOST=TRUE to the recursive
cmake invocations, so that cmake files can distinguish these recursive
invocations from top-level ones, which can explain why expected options
are unset.
LLILC will use this to avoid trying to generate its build rules in the
crosscompile native host target (where it is not needed), which would fail
if attempted because LLILC requires a cmake variable passed on the command
line, which is not forwarded in the recursive invocation.
Reviewers: rnk, beanz
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D12679
llvm-svn: 247151
* put most of the cross-compiling support into a function llvm_create_cross_target_internal.
* when CrossCompile is included it still generates a NATIVE target.
* llvm_create_cross_target function takes a target_name which should match a toolchain.
* llvm_create_cross_target can now be used to target more than one cross-compilation target.
llvm-svn: 232067
The basic idea is similar to the existing cross compilation support. A directory must be configured to build host versions of tablegen tools and llvm-config. This directory can be user provided (and configured), or it can be created during the build. During a build the native build directory will be configured and built to supply the tablegen tools used during the build. A user could also explicitly provide the tablegen executables to run on the CMake command line.
llvm-svn: 217105