Duncan P. N. Exon Smith 49135bb76c Don't upgrade global constructors when reading bitcode ... An optional third field was added to `llvm.global_ctors` (and `llvm.global_dtors`) in r209015. Most of the code has been changed to deal with both versions of the variables. Users of the C API might create either version, the helper functions in LLVM create the two-field version, and clang now creates the three-field version. However, the BitcodeReader was changed to always upgrade to the three-field version. This created an unnecessary inconsistency in the IR before/after serializing to bitcode. This commit resolves the inconsistency by making the third field truly optional (and not upgrading in the bitcode reader). Since `llvm-link` was relying on this upgrade code, rather than deleting it I've moved it into `ModuleLinker`, where it upgrades these arrays as necessary to resolve inconsistencies between modules. The ideal resolution would be to remove the 2-field version and make the third field required. I filed PR20506 to track that. I changed `test/Bitcode/upgrade-global-ctors.ll` to a negative test and duplicated the `llvm-link` check in `test/Linker/global_ctors.ll` to check both upgrade directions. Since I came across this as part of PR5680 (serializing use-list order), I've also added the missing `verify-uselistorder` RUN line to `test/Bitcode/metadata-2.ll`. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215457 91177308-0d34-0410-b5e6-96231b3b80d8		2014-08-12 16:46:37 +00:00
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CMakeLists.txt	Now that Linker.cpp is almost empty, merge it into LinkModules.cpp.	2013-05-04 03:48:37 +00:00
LinkModules.cpp	Don't upgrade global constructors when reading bitcode	2014-08-12 16:46:37 +00:00
LLVMBuild.txt	[Linker] Kill Linker::LoadObject which is dead, and drop the BitReader dependency again.	2013-01-18 19:37:11 +00:00
Makefile