freebsd-dev/share/man
Dimitry Andric cbafd2630b Add support for selectively enabling LLVM targets
This makes it possible, through src.conf(5) settings, to select which
LLVM targets you want to build during buildworld.  The current list is:

* (WITH|WITHOUT)_LLVM_TARGET_AARCH64
* (WITH|WITHOUT)_LLVM_TARGET_ARM
* (WITH|WITHOUT)_LLVM_TARGET_MIPS
* (WITH|WITHOUT)_LLVM_TARGET_POWERPC
* (WITH|WITHOUT)_LLVM_TARGET_SPARC
* (WITH|WITHOUT)_LLVM_TARGET_X86

To not influence anything right now, all of these are on by default, in
situations where clang is enabled.

Selectively turning a few targets off manually should work.  Turning on
only one target should work too, even if that target does not correspond
to the build architecture.  (In that case, LLVM_NATIVE_ARCH will not be
defined, and you can only use the resulting clang executable for
cross-compiling.)

I performed a few measurements on one of the FreeBSD.org reference
machines, building clang from scratch, with all targets enabled, and
with only the x86 target enabled.  The latter was ~12% faster in real
time (on a 32-core box), and ~14% faster in user time.  For a full
buildworld the difference will probably be less pronounced, though.

Reviewed by:	bdrewery
MFC after:	1 week
Differential Revision: https://reviews.freebsd.org/D11077
2018-06-22 15:00:00 +00:00
..
man1 share: normalize paths using SRCTOP-relative paths or :H when possible 2017-03-04 11:26:40 +00:00
man3 Depart from normal man page proactice a little and provide guidance on 2018-05-31 14:23:33 +00:00
man4 Sometimes it is helpful to get the path for a vnode. 2018-06-20 08:34:29 +00:00
man5 Add support for selectively enabling LLVM targets 2018-06-22 15:00:00 +00:00
man6 Update intro(6) - remove hint that doesn't work, add explicit list 2017-11-27 12:39:35 +00:00
man7 "Kernel APIs" is a misnomer; use the proper name instead. 2018-06-21 08:19:11 +00:00
man8 Document the new ${name}_env_file feature 2018-06-19 19:27:37 +00:00
man9 epoch.9: bump Dd 2018-06-22 06:05:19 +00:00
Makefile