forked from OSchip/llvm-project
56cc990480
During LTO, user-supplied definitions of C library functions often exist. -instcombine uses Module::getOrInsertFunction() to get a handle on library functions (e.g., @puts, when optimizing @printf). Previously, Module::getOrInsertFunction() would rename any matching functions with local linkage, and create a new declaration. In LTO, this is the opposite of desired behaviour, as it skips by the user-supplied version of the library function and creates a new undefined reference which the linker often cannot resolve. After some discussing with Rafael on the list, it looks like it's undesired behaviour. If a consumer actually *needs* this behaviour, we should add new API with a more explicit name. I added two testcases: one specifically for the -instcombine behaviour and one for the LTO flow. <rdar://problem/16165191> llvm-svn: 203513 |
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| .. | ||
| cfi_endproc.ll | ||
| current-section.ll | ||
| keep-used-puts-during-instcombine.ll | ||
| linkonce_odr_func.ll | ||
| lit.local.cfg | ||
| no-undefined-puts-when-implemented.ll | ||
| private-symbol.ll | ||
| runtime-library.ll | ||
| triple-init.ll | ||