ZJIT: Implement getlocal and setlocal (for nested scopes) #13689
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EDIT: fixed |
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Also added 2 minor cleanups. |
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| 1.times do |l2| | ||
| 1.times do |l1| | ||
| define_method(:test) do | ||
| l1 = 1 | ||
| l2 = 2 | ||
| l3 = 3 | ||
| [l1, l2, l3] | ||
| end | ||
| end | ||
| end |
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This PR adds support for the inner functions to write to outer locals but it doesn't look like it modifies those outer functions to handle their locals being written to
What I mean is if you read from l2 in the outer 1.times loop, you will see a getlocal_WC_0 which we have folded away in our bytecode->IR pass. In other words, we'll miss the fact that the inner function writes to the frame.
I think this happens to "work" accidentally right now because we abort compiling if we have send with block (Send) and therefore never have a JIT compiled function have its locals modified like this.
Since block ISEQs are known statically, we can/should detect this kind of nested scope local writing in the block ISEQs and penalize the locals in the upper frame(s) that might get written to like this.
I don't know that there is necessarily a full fix needed in this current PR, but:
- We should write this down somewhere, probably a TODO in the code and a Ruby issue, and
- We should add a test for catching that local being written to from a nested ISEQ; it will pass right now
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Maybe it's a bad guess but I kind of expect upper-local writes like this to be common but other get-my-caller-and-write-its-locals shenanigans to be more rare.
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👍🏼 6e85878. Actually, the test fails right now because assert_compile() catches that Send doesn't compile. So I'm checking it in as skipped for now. Shopify#596
They're only used when level≠0. Same EP hopping logic as interpreter and YJIT. Change assert_compiles() to get ISeq by method name since the old code didn't support methods defined using define_method() which I need for the new test.
getlocalandsetlocalto HIR