This commit introduces the `serde` dependency, which we will use to
serialize messages going between processes in multiprocess Servo.
This also adds a new debugging flag, `-Z print-display-list-json`,
allowing the output of display list serialization to be visualized.
This will be useful for our experiments with alternate rasterizers.
process parts.
This will make it easier to adapt to IPC.
The trickiest part here was to make script tasks spawn new layout tasks
directly instead of having the pipeline do it for them. The latter
approach will not work in multiprocess mode, because layout and script
must run in the same address space and the pipeline cannot inject tasks
into another process.
Reduce the scope of the allowed unsafe code in context.rs.
Since I made unsafe code opt-in in layout, the unsafe code in this module has
been reduced to a single unsafe impl, so there is no reason to allow it in
the entire module.
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Since I made unsafe code opt-in in layout, the unsafe code in this module has
been reduced to a single unsafe impl, so there is no reason to allow it in
the entire module.
Fix for #6542 - <img> top-padding adds margin
I wrote this patch that makes the test from #6542 render as expected but I am not confident it is actually the right fix. Should the padding be included in the 'ascent' metric for images, or am I just introducing a bug that happens to offset the one I'm trying to fix?
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Borrow the QueueData for WorkQueue::run.
This allows us to get rid of the raw pointers and unsafe dereferencing in
the parallel layout implementation.
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layout: Disable parallel display list building by default.
I've never see it result in a speedup. Actually, I don't think I've seen
it result in anything better than a 50% slowdown. The arithmetic
intensity is just too low, at least with the current algorithm.
Parallel DL building can still be enabled with a debug flag if the
algorithm is improved.
r? @metajack
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Use a dedicated type for the opaque type parameter to WorkQueue in layout.
Currently, we use UnsafeFlow and UnsafeLayoutNode, both of which are aliases
for (usize, usize) and thus interconvertible. This change should make it
clearer that the WorkQueue is not limited to one particular type.
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