forked from OSchip/llvm-project
2f0cc477ab
Summary: Until a more advanced version of importing can be implemented for aliases (one that imports an alias as an available_externally definition of the aliasee), skip the narrow subset of cases that was possible but came at a cost: aliases of linkonce_odr functions could be imported because the linkonce_odr function could be safely duplicated from the source module. This came/comes at the cost of not being able to 'home' imported linkonce functions (they had to be emitted linkonce_odr in all the destination modules (even if they weren't used by an alias) rather than as available_externally - causing extra object size). Tangentially, this also was the only reason ThinLTO would emit multiple CUs in to the resulting DWARF - which happens to be a problem for Fission (there's a fix for this in GDB but not released yet, etc). (actually it's not the only reason - but I'm sending a patch to fix the other reason shortly) There's no reason to believe this particularly narrow alias importing was especially/meaningfully important, only that it was /possible/ to implement in this way. When a more general solution is done, it should still satisfy the DWARF concerns above, since the import will still be available_externally, and thus not create extra CUs. Since now all aliases are treated the same, I removed/simplified some test cases since they were testing corner cases where there are no longer any corners. Reviewers: tejohnson, mehdi_amini Differential Revision: https://reviews.llvm.org/D35875 llvm-svn: 309278 |
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| .. | ||
| Inputs | ||
| alias_import.ll | ||
| alias_resolution.ll | ||
| autoupgrade.ll | ||
| cache-config.ll | ||
| cache-import-lists.ll | ||
| cache-typeid-resolutions.ll | ||
| cache.ll | ||
| cfi-icall.ll | ||
| crash_debuginfo.ll | ||
| deadstrip.ll | ||
| debuginfo-compositetype-import.ll | ||
| debuginfo-cu-import.ll | ||
| diagnostic-handler-remarks-with-hotness.ll | ||
| diagnostic-handler-remarks.ll | ||
| dicompositetype-unique.ll | ||
| distributed_import.ll | ||
| distributed_indexes.ll | ||
| drop-debug-info.ll | ||
| emit_imports.ll | ||
| empty_module_with_cache.ll | ||
| export.ll | ||
| funcimport-tbaa.ll | ||
| funcimport.ll | ||
| funcimport2.ll | ||
| import_opaque_type.ll | ||
| internalize.ll | ||
| lazyload_metadata.ll | ||
| linkonce_aliasee_ref_import.ll | ||
| linkonce_resolution_comdat.ll | ||
| lit.local.cfg | ||
| llvm.used.ll | ||
| local_name_conflict.ll | ||
| merge-triple.ll | ||
| module_asm2.ll | ||
| module_asm_glob.ll | ||
| newpm-basic.ll | ||
| prefix_replace.ll | ||
| reference_non_importable.ll | ||
| referenced_by_constant.ll | ||
| save_objects.ll | ||
| section.ll | ||
| tli-nobuiltin.ll | ||
| weak_resolution.ll | ||
| weak_resolution_single.ll | ||