Box the generator wrapper as a heap-allocated ObjectType instead of a value tuple - #245
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… value tuple
Object literals in this compiler compile to value-typed tuples by default,
even though the generator wrapper ({step, next()}) has mutable identity that
must be shared across aliases. This meant passing a generator to a function,
capturing it in a closure, or reassigning it (const b = a) all silently
copied its state instead of aliasing it.
Add InternalFlags::BoxAsObject to mark the synthetic wrapper literal built by
buildGeneratorWrapperDeclaration, and heap-box it (NewOp + StoreOp + CastOp,
the same recipe castTupleToInterface already uses) into ObjectType instead of
leaving it as a tuple. Property access on ObjectType already emits a
PropertyRefOp directly on the pointer, so .next() now mutates shared storage
for every alias.
Supersedes the const-storage-only fix in #244 for generators specifically,
and fixes the parameter-aliasing bug that fix explicitly left open.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
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… tuple cast (#248) Generalizes the generator-wrapper's BoxAsObject boxing (PR #245) toward supporting any object literal with methods: getFields now looks through ObjectType to its storage type, object spread ({...obj}) handles a boxed ObjectType source, and castTupleLikeVariants gained an ObjectType->tuple unboxing cast. No behavior change for existing code paths; verified via generator objects (the only literals boxed today) in new test 00object_boxed_infra.ts. Full suite: 352/352 JIT + 356/356 AOT. See docs/object-literal-boxing-design.md for the full staged plan (this is PR A of three). Co-authored-by: Claude Sonnet 5 <noreply@anthropic.com>
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…ype (#249) Generalizes the generator-wrapper's BoxAsObject boxing (PR #245, PR #248) to any object literal with a method or accessor: mlirGen(ObjectLiteralExpression) now boxes whenever oli.methodInfos/methodInfosWithCaptures is non-empty, not just synthetic wrappers carrying the flag. Every alias of such a literal (second binding, parameter, closure capture, array/object element) now shares mutable state, matching JS semantics; pure-data literals keep value (struct) semantics. The flip itself is two lines, but exercising ObjectType through every path that previously only saw tuples for method-bearing literals surfaced five more missing ObjectType cases, each fixed: - boxing seed value routed through mlirGenCreateTuple instead of the generic cast pipeline, avoiding a spurious "losing this reference" warning - TupleGetSetAccessor's get/set now handles a pointer (ObjectType/RefType) operand via PropertyRefOp+LoadOp, not just ExtractPropertyOp - castObjectToInterface gained the same field-type-coercion fallback castTupleToInterface already had (e.g. si32 vs number) - element access (obj[Symbol.x]) dispatches ObjectType like Class/Interface - generic intersection-type merge (D & M) and parameter inference look through ObjectType's storage type, same as MLIRTypeHelper::getFields New test 00object_ref_semantics.ts covers alias mutation through bindings, parameters, closures, array/object elements, accessors, globals, and conditional-expression merges. Full suite green: 353/353 JIT + 357/357 AOT. See docs/object-literal-boxing-design.md (PR B of three staged PRs). Co-authored-by: Claude Sonnet 5 <noreply@anthropic.com>
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Summary
{step, next()}, built bybuildGeneratorWrapperDeclaration) has mutable identity (stepadvanced by.next()) but was still a value tuple — so passing a generator to a function, capturing it in a closure, or reassigning it (const b = a) all silently copied its state instead of aliasing it.InternalFlags::BoxAsObjectflag and heap-box it intomlir_ts::ObjectType(NewOp+StoreOp+CastOp— the same recipecastTupleToInterfacealready uses) instead of leaving it as a tuple. Property access onObjectTypealready emits aPropertyRefOpdirectly on the pointer, so.next()now mutates shared storage for every alias.for...of/yield*/destructuring needed no changes — they discovernextthrough generic property access, which already handlesObjectType.docs/generator-object-wrapper-design.md(chosen approach, implemented) anddocs/generator-param-by-ref-design.md(a RefType-parameter alternative that was analyzed and rejected for its function-type-equality blast radius — kept for the record).Test plan
00generator_manual_next.ts,00generator7.tspass via JIT00generator_manual_next2.tsextended with permanent regression coverage for parameter aliasing (caller observes callee's.next()calls), closure-capture aliasing, and plain-assignment aliasing — all passthistype mismatch this fix addresses)🤖 Generated with Claude Code