[Impeller] Emplace directly into host buffer (avoid VBB) for text data #42484
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impeller/core/host_buffer.h
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| /// | ||
| /// @return The buffer view. | ||
| /// | ||
| BufferView EmplaceCallback(size_t length, |
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Nit: I'd rather just take advantage of function overloading and use the name Emplace.
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I suspect we will only use this sparingly for performance but its good to have the open as needed.
impeller/core/host_buffer.h
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| using EmplaceProc = std::function<void(uint8_t* buffer)>; | ||
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| //---------------------------------------------------------------------------- | ||
| /// @brief Emplace non-uniform data (like contiguous vertices) onto the |
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"Emplaces undefined data onto the managed buffer and gives the caller a chance to update it using the specified callback. The buffer is guaranteed to have enough space for length bytes. It is the responsibility of the caller to not exceed the bounds of the buffer returned in the EmplaceProc.".
| return {}; | ||
| } | ||
| generation_++; | ||
| cb(GetBuffer() + old_length); |
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Emplace and EmplaceCallback can be dried up by making Emplace call EmplaceCallback with a callback that does the memmove.
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Also, let's check that CB is valid. If not, emplacing undefined data is fine.
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Alternatively consider making this return a std::pair
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e.g. std::pair<BufferView, uintptr_t> Reserve(size_t length, size_t align); and then on this line you
return std::make_pair(BufferView{...}, GetBuffer() + old_length);There was a problem hiding this comment.
Emplace could still be dried up as Chinmay is suggesting to internally call Reserve and use the pointer.
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LGTM, stylistic comments that are not meant to be blocking. |
jonahwilliams
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…128089) flutter/engine@3a453f2...02d6fbb 2023-06-01 [email protected] [Impeller] Emplace directly into host buffer (avoid VBB) for text data (flutter/engine#42484) 2023-06-01 [email protected] Ensure PlatformView engine life cycle callbacks are invoked (flutter/engine#42491) 2023-06-01 [email protected] Roll Skia from c408e8e9cc96 to 082a7d1f72f7 (8 revisions) (flutter/engine#42496) 2023-06-01 [email protected] [Windows - TextInput] Insert new line only when TextInputAction.newline (flutter/engine#42244) 2023-06-01 [email protected] Revert "Move clang tidy v2 build to prod." (flutter/engine#42495) 2023-06-01 [email protected] Add myself to AUTHORS (flutter/engine#42406) 2023-06-01 [email protected] [Impeller] Add Impeller Metal support in the embedder API (flutter/engine#42411) 2023-06-01 [email protected] Support DisposalMethod::kRestorePrevious in MultiFrameCodec and fix the apng problem. (flutter/engine#42153) 2023-06-01 [email protected] Fix crash getting spell-check suggestions (flutter/engine#42466) 2023-06-01 [email protected] Fix lint in rectangle packer (flutter/engine#42489) 2023-06-01 [email protected] Wait for GL command completion in the ExternalTextureGLRefreshedTooOften test (flutter/engine#42438) 2023-06-01 [email protected] Reland "[web] Remove the JS API for url strategy (#42134)" (flutter/engine#42486) 2023-06-01 [email protected] Roll Skia from f5bc3d12f0eb to c408e8e9cc96 (9 revisions) (flutter/engine#42487) 2023-06-01 [email protected] Clean up Skia includes around SkSurfaceCharacterization (flutter/engine#42485) If this roll has caused a breakage, revert this CL and stop the roller using the controls here: https://autoroll.skia.org/r/flutter-engine-flutter-autoroll Please CC [email protected],[email protected],[email protected] on the revert to ensure that a human is aware of the problem. To file a bug in Flutter: https://github.com/flutter/flutter/issues/new/choose To report a problem with the AutoRoller itself, please file a bug: https://bugs.chromium.org/p/skia/issues/entry?template=Autoroller+Bug Documentation for the AutoRoller is here: https://skia.googlesource.com/buildbot/+doc/main/autoroll/README.md
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From local testing, this shaves off about 0.3-4 ms of pure allocation overhead from flutter/flutter#127760
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