[BOLT] Always run CheckLargeFunctions in non-relocation mode #80922
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We run CheckLargeFunctions pass in non-relocation mode to prevent the emission of functions that later could not be written to the output due to their large size. The main reason behind the pass is to prevent the emission of metadata for such functions since this metadata becomes incorrect if the function is left unmodified. Currently, the pass is enabled in non-relocation mode only when debug info output is also enabled. As we emit increasingly more kinds of metadata, e.g. for the Linux kernel, it becomes more challenging to track metadata that needs to be fixed. Hence, I'm enabling the pass to always run in non-relocation mode.
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@mtvec, @yota9, I have added a couple of asserts that are x86-only. I found out that they are firing on RISC-V and Aarch64 which means |
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I agree, since currently we're calculating true size separately in LongJmp for aarch64 like It would be better to incorporate this code to BF-specific size calculation function |
| @@ -3631,6 +3631,7 @@ void RewriteInstance::mapCodeSections(BOLTLinker::SectionMapper MapSection) { | |||
| Function.setImageAddress(FuncSection->getAllocAddress()); | |||
| Function.setImageSize(FuncSection->getOutputSize()); | |||
| if (Function.getImageSize() > Function.getMaxSize()) { | |||
| assert(!BC->isX86() && "Unexpected large function."); | |||
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To clarify the question, could you test it on your side with assertion changed to check for CIs? Ideally, the check should be properly modified to accommodate for CIs on supported architectures.
We run CheckLargeFunctions pass in non-relocation mode to prevent the emission of functions that later could not be written to the output due to their large size. The main reason behind the pass is to prevent the emission of metadata for such functions since this metadata becomes incorrect if the function is left unmodified.
Currently, the pass is enabled in non-relocation mode only when debug info output is also enabled. As we emit increasingly more kinds of metadata, e.g. for the Linux kernel, it becomes more challenging to track metadata that needs to be fixed. Hence, I'm enabling the pass to always run in non-relocation mode.