fix(opt): visit input operand of AtomicOp::CompareAndSwap#1331
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kimjune01 wants to merge 1 commit into
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fix(opt): visit input operand of AtomicOp::CompareAndSwap#1331kimjune01 wants to merge 1 commit into
kimjune01 wants to merge 1 commit into
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The optimizer's visit_atomic handler for CompareAndSwap visited op.cmp twice and never visited op.input. This meant the atomic pointer variable was not tracked as read, so the optimizer could break the binding chain between the Index op (which registers the atomic scope) and the CAS op (which looks it up), causing "Atomic should have a scope registered" panics in cubecl-spirv. Also fixes the duplicate visit of op.cmp (copy-paste bug). Fixes tracel-ai#1318
kimjune01
marked this pull request as draft
May 17, 2026 20:09
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Human here. Unfortunate news: I just moved this into drafts because I just realized that I can't repro the issue locally anymore. I quit my job this past week and no longer have access to a linux or windows machine like I used to. I'm on a macbook pro now. I wish I could've taken it to completion by actually running the tests. Thanks for understanding |
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Fixes #1318.
visit_atomicforCompareAndSwapvisitedop.cmptwice and never visitedop.input. The atomic pointer variable therefore wasn't tracked as read, and the optimizer could break the binding chain between theIndexop (which registers the atomic scope) and theCASop (which looks it up). The downstream effect was theAtomic should have a scope registeredpanic incubecl-spirv.This change visits
op.inputand removes the duplicate visit ofop.cmp(a copy-paste bug).Testing
cargo xtask validatepasses.Hypothesis graph
Investigation notes and the repo-level hypothesis graph that informed this fix: https://github.com/kimjune01/sweep/blob/master/repo-hypotheses/tracel-ai-cubecl.md