[wasm-merge] Handle table initializer referring to imported global - #9167
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Unlike global initializers and element segments (which under GC may refer to preceding module-defined globals), a table initializer expression may only refer to imported globals. Fusing can turn an imported global that a table initializer refers to into a module-defined one, which would make the initializer invalid. When that happens, inline the referenced global's (immutable, constant) value so the initializer remains valid.
kripken
reviewed
Sep 29, 2026
| struct Inliner : public PostWalker<Inliner> { | ||
| bool inlined = false; | ||
| void visitGlobalGet(GlobalGet* curr) { | ||
| auto* global = getModule()->getGlobalOrNull(curr->name); |
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How can the result here be null? I think we can use getGlobal()?
kripken
reviewed
Sep 29, 2026
| // global's initializer refers to another one), so iterate to a fixed point. | ||
| // Globals cannot form cycles, so this terminates. Any global.gets that | ||
| // remain refer to imported globals, which are valid in table initializers. | ||
| while (true) { |
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Please add a second testcase that adds coverage for the looping.
kripken
approved these changes
Oct 1, 2026
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Unlike global initializers and element segments (which under GC may refer to preceding module-defined globals), a table initializer expression may only refer to imported globals. Fusing can turn an imported global that a table initializer refers to into a module-defined one, which would make the initializer invalid. When that happens, inline the referenced global's (immutable, constant) value so the initializer remains valid.