Surface rename of the signed integer family: s1..s64 become i1..i64
(u1..u64, usize, isize unchanged). 'string' keeps the s-prefix arm in
name classification; width parsing moves to the i-prefix arm next to
isize.
Internal TypeId tags follow the surface (.s8/.s16/.s32/.s64 ->
.i8/.i16/.i32/.i64), as do mono-key mangle fragments (ptr_i64,
tu_i64_bool) and all display/diagnostic formatting (i{d}).
Migrated in the same sweep: stdlib + examples + issue repros + FFI C
companions (shared symbol names like ffi_id_i64), expected
stdout/stderr/ir snapshots, specs.md, readme.md, CLAUDE.md/AGENTS.md,
implementation_plan.md, docs/, issue writeups. Vendored stb_image and
historical flow state left untouched.
zig build test: 426/426; examples suite: 595/595.
Move the pure Obj-C decision helpers out of lower.zig into src/ir/ffi_objc.zig
behind an ObjcLowering *Lowering facade (Principle 5, like the A4/A5 resolvers).
Behavior-preserving relocation — the only non-self.l rewrites are facade
plumbing.
Moved verbatim (self. -> self.l. for Lowering members):
- deriveObjcSelector (selector derivation)
- objcTypeEncodingFromSignature + appendObjcEncoding + bailObjcEncoding +
the ObjcEncodingStack type
- objcPropertyKind + the ObjcPropertyKind enum
- isObjcClassPointer
- objcDefinedStateStructType + objcStateAllocatorType
Emission-heavy code stays in lower.zig per PLAN A6.1 step 6: emitObjc* IMP
builders, lowerObjc*Call, registerObjc*, declareObjc*, the lookupObjc* property/
state lookups, and the Self-substitution resolvers.
- Call sites rerouted through a new objc() accessor: 15 in lower.zig, 1 in
expr_typer.zig, 39 in lower.test.zig (the A6.1 scaffolding tests now drive the
facade). No Lowering wrappers kept. Barrel-wired ffi_objc + ObjcLowering.
- No new visibility widening beyond sub-step 1's two pubs — the facade reads
self.l.{alloc,module,program_index,diagnostics} (fields) + the already-pub
resolveType. lower.zig -478 (->16615); ffi_objc.zig 428.
- Doc-only re-home: the property-IMP getter/setter comment was attached (a
pre-existing artifact) to the moving ObjcPropertyKind enum, two decls away from
its real subject emitObjcDefinedClassPropertyImps (which had no doc). Re-homed
it there so the move neither orphans a `///` block (Zig errors on a dangling doc
comment) nor misattributes it to ensureArcRuntimeDecls.
Gate: zig build, zig build test, bash tests/run_examples.sh -> 361/0
(48 13xx Obj-C examples + 4 Obj-C .ir snapshots green, no churn).
