Added detail to codegen section #1216
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| thread to generate work for them. If `parallel_compiler` _is_ true, the LLVM queue is | ||
| loaded in parallel. | ||
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| At the end, the linker is ran and combines all the compiled codegen units together into one binary. |
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nit:
| At the end, the linker is ran and combines all the compiled codegen units together into one binary. | |
| At the end, the linker is run and combines all the compiled codegen units together into one binary. |
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| At the end, the linker is ran and combines all the compiled codegen units together into one binary. | |
| At the end, the compiled codegen units together into the final artifact. For binary executable results this is done by a linker. |
Executable binary is not the only kind of the output we have. rlibs, sos and os are some of the others.
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@nagisa I think your suggestion may be missing the words "are combined together" or similar.
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@nagisa Could you give this a review? Feel free to reassign by the way :) |
| Once the partitions have been sorted, the smallest and largest halves are iterated over separately. | ||
| Their elements are paired and stored in a `Vec` so that the largest | ||
| and smallest partitions are first and second, the second largest and smallest are | ||
| third and fourth, and so on. These partitions are then translated into LLVM-IR. |
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I think it is misleading to mention LLVM IR explicitly, especially now that there are 5+ rustc codegens for all kinds of IRs. It should mention that a codegen backend is invoked to translate the cgu to its particular IR. Especially because you dont mention cg_llvm, only cg_ssa, and cg_ssa does not do any llvm things.
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I also don't think its all that important to talk about the particularities of how the order of the CUs to translate is established. It suffices to say, I feel, that the compiler partition and order the CUs in an effort to [... whatever the goals are at the given time...]
| the largest partitions would be in memory at the same time; increasing memory consumption and | ||
| impacting overall performance. | ||
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| Once the partitions have been organized they must be translated into LLVM-IR, where they are |
| - A `rustc` version of an [OwningRef][OwningRef] | ||
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| First, we collect and partition the [monomorphized][monomorphization] version of the program | ||
| that has been compiled. The individual partitions are then sorted from largest to smallest. |
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| that has been compiled. The individual partitions are then sorted from largest to smallest. | |
| that is being compiled. The individual partitions are then sorted from largest to smallest. |
| Once the partitions have been sorted, the smallest and largest halves are iterated over separately. | ||
| Their elements are paired and stored in a `Vec` so that the largest | ||
| and smallest partitions are first and second, the second largest and smallest are | ||
| third and fourth, and so on. These partitions are then translated into LLVM-IR. |
There was a problem hiding this comment.
I also don't think its all that important to talk about the particularities of how the order of the CUs to translate is established. It suffices to say, I feel, that the compiler partition and order the CUs in an effort to [... whatever the goals are at the given time...]
| thread to generate work for them. If `parallel_compiler` _is_ true, the LLVM queue is | ||
| loaded in parallel. | ||
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| At the end, the linker is ran and combines all the compiled codegen units together into one binary. |
There was a problem hiding this comment.
| At the end, the linker is ran and combines all the compiled codegen units together into one binary. | |
| At the end, the compiled codegen units together into the final artifact. For binary executable results this is done by a linker. |
Executable binary is not the only kind of the output we have. rlibs, sos and os are some of the others.
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@Sl1mb0 Triage ping, could you address the review comments above? |
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I'm going to close this as inactive but feel free to re-open another PR or pick up their work if anyone is interested in continuing the work, thanks for contributing! |
This provides more in-depth descriptions of the parallelism occurring during codegen. There are probably a few things I got wrong conceptually, so don't hesitate to point them out :)