Teresa Johnson 5cb3a1fa72 Restore "Move metadata linking after lazy global materialization/linking." ... Summary: This reverts commit r251965. Restore "Move metadata linking after lazy global materialization/linking." This restores commit r251926, with fixes for the LTO bootstrapping bot failure. The bot failure was caused by references from debug metadata to otherwise unreferenced globals. Previously, this caused the lazy linking to link in their defs, which is unnecessary. With this patch, because lazy linking is complete when we encounter the metadata reference, the materializer created a declaration. For definitions such as aliases and comdats, it is illegal to have a declaration. Furthermore, metadata linking should not change code generation. Therefore, when linking of global value bodies is complete, the materializer will simply return nullptr as the new reference for the linked metadata. This change required fixing a different test to ensure there was a real reference to a linkonce global that was only being reference from metadata. Note that the new changes to the only-needed-named-metadata.ll test illustrate an issue with llvm-link -only-needed handling of comdat groups, whereby it may result in an incomplete comdat group. I note this in the test comments, but the issue is orthogonal to this patch (it can be reproduced without any metadata at head). Reviewers: dexonsmith, rafael, tra Subscribers: tobiasvk, joker.eph, llvm-commits Differential Revision: http://reviews.llvm.org/D14447 llvm-svn: 252320		2015-11-06 17:50:53 +00:00
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CMakeLists.txt	modules: Add explicit dependency on intrinsics_gen	2015-06-16 00:44:12 +00:00
LinkModules.cpp	Restore "Move metadata linking after lazy global materialization/linking."	2015-11-06 17:50:53 +00:00
LLVMBuild.txt
Makefile