Change Details

When placed on a global variable, !associated tells the optimizer (DCE in particular) to treat all global references in that variable's initializer as reverse dependencies.

This is an ELF-specific thing that adds SHF_LINK_ORDER to the global's section pointing to the metadata argument's section. The effect of that is a reverse dependency between sections for the linker GC. !associated does not change the behavior of global-dce. The global may also need to be added to llvm.compiler.used. Since SHF_LINK_ORDER is per-section, !associated effectively enables fdata-sections for the affected globals, the same as comdats do

When placed on a global variable, !associated tells the optimizerThis is an ELF-specific thing that adds SHF_LINK_ORDER to the global's section pointing to the metadata argument's section. The effect of that is a reverse dependency (DCE in particular) to treat allassociated does not change the behavior of global references in that variable's-dce. The global initializer as reverse dependencies.may also need to be added to llvm.compiler.used. Since SHF_LINK_ORDER is per-section, !associated effectively enables fdata-sections for the affected globals, the same as comdats do