generate JIT argument type information for methods
This enhances `CodegenRust.py` to output `JSTypedMethodJitInfo` structures where appropriate. This brings a notable speedup to tests like Dromaeo's `dom-attr/getAttribute`, which improves by several orders of magnitude with these patches applied.
If there are tricks for addressing the XXX comments, I would appreciate hearing them.
I think this addresses all of #6904.
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These are copied directly from Gecko's Codegen.py, with two changes:
- We need to use ArgType:: to qualify the enums rather than plain
JSJitInfo::
- Given Rust's stronger notion of enums, we need to treat everything as an
i32 so we can bitwise-or things together.
Fix start and end points for linear gradients with angle specified.
Previously, this was most noticeable with 45deg gradients, where the gradient would end too early, and the remainder was filled with a solid color.
(This also fixes gradients on webrender, which relies on the start and stop points being correct).
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Return the result from query functions.
This reduces some unnecessarily tight coupling, makes it clearer what these functions do, and may help avoid bugs where we would return from such a function without updating the relevant field.
It is also a precondition for some future experimentation I'm thinking of doing with this querying design.
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Make unrooted_must_root a bit more aggressive.
Basically, instead of trying to check for specific kinds of statements,
just check the types of all local variables.
Also included are some commented-out proposals for some slightly more
aggressive lints which might be useful (but trigger a little too
frequently at the moment).
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Integrate Canvas into the DisplayList
Canvas is currently given a layer at the stacking context level.
Instead it's DisplayItem should be given a layer directly. This fixes
painting order issues where canvases are painted on top of other
positioned content that is later in tree order. It always simplifies
the code a bit.
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