Commit Graph

13 Commits

Author SHA1 Message Date
Rafael Espindola
33f1a430c2 Be less conservative about when we build the gold plugin.
It is only build if LLVM_BINUTILS_INCDIR is explicitly given, so there is
no point in having extra restrictions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223481 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-05 17:25:52 +00:00
Rafael Espindola
3fd7e37b34 Rewrite the gold plugin to fix pr19901.
There is a fundamental difference between how the gold API and lib/LTO view
the LTO process.

The gold API talks about a particular symbol in a particular file. The lib/LTO
API talks about a symbol in the merged module.

The merged module is then defined in terms of the IR semantics. In particular,
a linkonce_odr GV is only copied if it is used, since it is valid to drop
unused linkonce_odr GVs.

In the testcase in pr19901 both properties collide. What happens is that gold
asks us to keep a particular linkonce_odr symbol, but the IR linker doesn't
copy it to the merged module and we never have a chance to ask lib/LTO to keep
it.

This patch fixes it by having a more direct implementation of the gold API. If
it asks us to keep a symbol, we change the linkage so it is not linkonce. If it
says we can drop a symbol, we do so. All of this before we even send the module
to lib/Linker.

Since now we don't have to produce LTO_SYMBOL_SCOPE_DEFAULT_CAN_BE_HIDDEN,
during symbol resolution we can use a temporary LLVMContext and do lazy
module loading. This allows us to keep the minimum possible amount of
allocated memory around. This should also allow as much parallelism as
we want, since there is no shared context.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216215 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-21 20:28:55 +00:00
Rafael Espindola
0b5745abd8 Use lib/LTO directly in the gold plugin.
The tools/lto API is not the best choice for implementing a gold plugin. Among
other issues:

* It is an stable ABI. Old errors stay and we have to be really careful
  before adding new features.
* It has to support two fairly different linkers: gold and ld64.
* We end up with a plugin that depends on a shared lib, something quiet
  unusual in LLVM land.
* It hides LLVM. For some features in the gold plugin it would be really
  nice to be able to just get a Module or a GlobalValue.

This change is intended to be a very direct translation from the C API. It
will just enable other fixes and cleanups.

Tested with a LTO bootstrap on linux.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211315 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-19 21:14:13 +00:00
Rafael Espindola
c540920a24 Don't mix the plain and keyword signatures of target_link_libraries.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202299 91177308-0d34-0410-b5e6-96231b3b80d8
2014-02-26 20:39:28 +00:00
Tom Roeder
69051578c7 Space formatting fix for r198966.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198971 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-10 23:17:39 +00:00
Tom Roeder
48324ba825 Fixing build break: should be in the if statement, not outside.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198966 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-10 22:55:25 +00:00
Tom Roeder
b2c6a6c0bd Restore the library dependency of LLVMgold on LTO; this was removed recently but
is needed for LLVMgold to load in ld.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198965 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-10 22:48:35 +00:00
Nico Weber
b6fe25c476 EXPORTED_SYMBOL_FILE support for cmake
The cmake build didn't support EXPORTED_SYMBOL_FILE. Instead, it had a
Windows-only implementation in tools/lto/CMakeLists.txt, a linux-only
implementation in tools/gold/CMakeLists.txt, and a darwin-only implementation
in tools/clang/tools/libclang/CMakeLists.txt.

This attempts to consolidate these one-offs into a single place. Clients can now
just set LLVM_EXPORTED_SYMBOL_FILE and things (hopefully) Just Work, like in
the make build.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198136 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-28 23:31:44 +00:00
Peter Collingbourne
5d0f76199b Use absolute path to exportsfile in gold plugin CMake build.
(Ninja generator requirement.)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143783 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-05 04:17:20 +00:00
Oscar Fuentes
be5d9b0bdc CMake builds gold by default since revision 127466. This is
inconsistent with autoconf, which by default set BINUTILS_INCDIR to
empty and exclude gold from target list.

Based on a patch by Haitao Li!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@131229 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-12 11:26:21 +00:00
Oscar Fuentes
4839ded3bd Force re-linking of LLVMgold.so when its exports file changes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127473 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-11 18:27:13 +00:00
Oscar Fuentes
aa1fbb40ad Fix processing of gold.exports.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127471 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-11 18:07:46 +00:00
Oscar Fuentes
1dc550b383 Add LTO and gold plugin to the CMake build. Linux-only, support for
other systems pending.

PR9456.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127466 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-11 15:44:24 +00:00