[BasicBlockSections] Allow mixing of -basic-block-sections with MFS. #117076
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rlavaee
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| // Do not split functions when -basic-block-sections=all is specified. | ||
| if (MF.getTarget().getBBSectionsType() == llvm::BasicBlockSection::All) | ||
| return false; |
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Do you intend to support this combination in the future? I think basic block sections is useful for mapping in general beyond it's use in Propeller. If I recall correctly @boomanaiden154 mentioned this type of usage.
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Yes. This applies for AutoFDO builds. The idea is to apply Propeller for functions whose BasicBlockAddressMap structure doesn't change since the profile was collected (even though those functions may have been optimized by autofdo).
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For mapping, we just use the basic block address map rather than basic block sections as we only need to know where blocks are and their size rather than any ability to rearrange/GC them in the linker.
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Thanks for the quick review! |
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This PR allows mixing
-basic-block-sectionswith-enable-machine-function-splitter. The strategy is to let-basic-block-sectionstake precedence over functions with profiles.