Commit Graph

188 Commits

Author SHA1 Message Date
agra
5a4a19b3ab ffi M5.A.next.4A.bare.1.B: bare $args lowers to []Type slice value
Step 4A final-slice fix. Bare `$<pack_name>` (no `[<int>]`)
in expression position now parses + lowers to a comptime
`[]Type` slice value carrying one `const_type(TypeId)` per
pack element.

Plumbing:

- src/ast.zig: new `ComptimePackRef { pack_name }` node +
  `comptime_pack_ref` variant in Data.
- src/parser.zig: `parsePrimary`'s `$` arm makes `[` optional
  after the pack name. With `[<int>]` → existing
  `pack_index_type_expr` (single Type value). Without → new
  `comptime_pack_ref` (whole pack as []Type).
- src/sema.zig: adds the no-op switch arms for the new node
  in `analyzeNode` and `findNodeAtOffset`.
- src/ir/lower.zig: `lowerExpr` arm reads `pack_arg_types[name]`
  and calls `buildPackSliceValue(arg_tys)`. The helper allocas
  a `[N x Any]` array, emits one `const_type(arg_tys[i])` per
  slot, then a slice `{data_ptr, len}` aggregate. No active
  binding → focused diagnostic + null slice placeholder. The
  IR slice element type is `Any` (matches the today's
  `Type → .any` mapping in type_bridge); the interp stores
  raw `.type_tag` Values directly (NOT Any-boxed) so
  `args[i]` at interp time reads a Type value.
- src/ir/emit_llvm.zig: relaxed `const_type` to silently emit
  undef-i64 instead of the previous stderr-noisy bail. Storage
  of Type values in runtime aggregates is harmless (undef in,
  undef out). Use-site misuse is caught by the bails on
  type_name/type_eq/has_impl and the bitcast guard.

`examples/170-pack-bare-value.sx` flips from the parse-error
lock-in to "0/1/3/4" — four call shapes of `len_of(..$args) ->
s64 { list := $args; return list.len; }`. The slice's `.len`
field carries the per-mono pack arity.

210/210 example tests + `zig build test` green.

The remaining 4A.bare slices (4 and 5) — resolveTypeArg
silent-arm fix for index_expr + smoke test of a real builder
walking $args — are separate commits per the cadence rule.
2026-05-27 19:10:37 +03:00
agra
fd03b5812f ffi M5.A.next.4.3: $args[$i] in expression position — source construction
Final slice of the .type_tag activation. Sx code can now
construct Type values through the `$<pack>[<int_literal>]`
syntax in expression position. Lowering emits the new
`const_type(TypeId)` opcode; the interp materialises
`Value.type_tag(TypeId)`; reflection intrinsics + cmp_eq
read it kind-honestly.

Plumbing:

- src/parser.zig: `parsePrimary` accepts `$<ident>[<int_literal>]`
  at the front of every expression. Emits a `pack_index_type_expr`
  AST node — same node already used in TYPE positions in step 3,
  now extended to expression positions.

- src/ir/lower.zig: two places teach the new node.
  - `lowerExpr` arm: looks up `pack_arg_types[name][index]`, emits
    `builder.constType(arg_tys[index])`. OOB / no-binding paths
    emit a focused diagnostic + a `constType(.void)` placeholder
    (loud failure preserves silent-error budget).
  - `resolveTypeArg` arm: the same lookup, but returns the
    TypeId directly. Used by the lower-time fast paths in
    `tryLowerReflectionCall` + `tryConstBoolCondition` so
    `type_name($args[0])`, `type_eq($args[0], s64)`, and
    `has_impl(...)` all see the bound TypeId rather than
    falling through to the `.s64` default that the silent-arm
    rule forbids.

The two arms ensure both runtime AND compile-time paths use
the same source-of-truth (`pack_arg_types`), so per-mono
dispatch via `inline if type_eq($args[0], s64) { ... }` folds
at compile time as expected.

`examples/169-pack-value-dispatch.sx` exercises both shapes:
- `type_name($args[0])` returns the per-mono concrete type
  name ("s64", "string", "f64").
- `inline if type_eq($args[0], s64) { ... }` ladder dispatches
  per-mono ("got s64", "got string", "got bool", "got other").

209/209 example tests + `zig build test` green.

What's now possible end-to-end:

  show :: (..$args) -> string => type_name($args[0]);
  show(42)    // "s64"
  show("hi")  // "string"

  describe :: (..$args) -> string {
      inline if type_eq($args[0], s64) { return "got s64"; }
      ...
  }

The "by the book" activation is complete:
- foundation (const_type opcode, interp variant, helpers) — 4.0
- interp reflection arms (type_name / type_eq / has_impl) — 4.1
- box_any/display audit + bitcast guard — 4.2
- source-language construction via $args[$i] — 4.3

Step 5 (generic Into(Block) impl in stdlib) is now fully
unblocked — its trampoline body can interpolate per-mono types
both in type positions AND in expression positions.
2026-05-27 18:52:41 +03:00
agra
55c72af68a ffi M5.A.next.4.2: audit box_any/unbox_any/display, guard bitcast
Step 6 + 7 of the .type_tag activation plan. Audit pass on the
Any-boxing and value-display paths to confirm `.type_tag`
flows cleanly OR fails loudly.

Audit findings:

- `box_any` (interp.zig:1168) stores fields[0] as `.int(TypeId)`
  for the Any-tag, fields[1] as the raw operand Value. A
  `.type_tag` operand becomes the value field — correct.
  Tag-field stays int-shaped across all Any boxes; value
  field can be any Value kind including type_tag.

- `unbox_any` (interp.zig:1176) returns fields[1] as-is —
  preserves whatever was stored. Correct for `.type_tag`.

- `any_to_string` (std.sx:316) has a `case type:` arm:
    case type: { s : string = xx val; result = s; }
  KNOWN GAP. Pre-`.type_tag`, the Any's value field was
  string-shaped (lower-time type_name folding to const_string).
  Now the value field will be `.type_tag(TypeId)`. The
  `xx val to string` cast becomes a shape mismatch. Deferred
  until source construction wires a path that surfaces this —
  the loud bitcast guard below catches the silent-fall-through
  case.

New guard:

- `bitcast` interp arm (interp.zig:664) now explicitly bails
  when source is `.type_tag` and target is anything OTHER than
  `.any` (boxing into Any) or the identity Type. Catches the
  case-type-arm scenario above + any other stale "xx val to
  string" path that would silently misinterpret a Type value.
  Diagnostic suggests using `type_name(val)` as the
  replacement.

No code changes in box_any / unbox_any (already correct).
208/208 example tests + `zig build test` green. No `.type_tag`
constructions exercised yet — the guards are dormant infrastructure
ready for when source construction surfaces them.
2026-05-27 18:47:32 +03:00
agra
9600ba5cdc ffi M5.A.next.4.1: interp arms for reflection builtins on .type_tag
Second slice of the .type_tag activation. The reflection
intrinsics (`type_name`, `type_eq`, `has_impl`) now have
interp-time implementations that read `.type_tag` Values
directly. Today's lower-time fast path (folding to
`const_string`/`const_bool` when the type arg is statically
resolvable) stays — these interp arms are the fallback path
for when lowering emits a real `builtin_call` because the
arg is interp-time-only (e.g. `args[i]` inside a builder body
where the pack element is bound at interp execution).

Plumbing:
- New BuiltinId entries: `type_name`, `type_eq`, `has_impl`.
- Interp arms in `execBuiltinInner`:
  - `type_name(t)`: reads `.type_tag` via `asTypeId`, looks up
    via `module.types.typeName`, dupes the slice into the
    interp allocator, returns `.string`. Non-`.type_tag` arg
    → `bailDetail` ("argument is not a Type value").
  - `type_eq(a, b)`: both args must be `.type_tag`; compares
    TypeIds. Either side missing → `bailDetail`.
  - `has_impl(P, T)`: bails with a "not yet wired" message —
    interp-time has_impl needs a queryable snapshot of the
    host's `protocol_thunk_map` + `param_impl_map`, which is
    its own follow-up slice. Static-arg has_impl still works
    via the lower-time `tryConstBoolCondition` fast path.
- emit_llvm: explicit arms for the three new builtins that
  log + map to undef-i64 (Type values are comptime-only; if
  one of these reaches LLVM emit, lowering produced wrong
  IR — the LLVM verifier downstream surfaces the offending
  site).

Three new Zig unit tests in interp.test.zig:
- `type_name builtin on type_tag` — emits a `builtin_call`
  to `type_name` with a `const_type(s64)` operand, asserts
  the result is the string "s64".
- `type_eq builtin on type_tag values` — two equal Type
  operands compare equal.
- (Pre-existing) `const_type yields type_tag` + `type_tag
  comparison` from 4.0 still pass.

208/208 example tests + `zig build test` green. No source-
language path constructs `.type_tag` yet — the foundation is
ready for the `$args`-in-expression-position slice that
turns it on for users.
2026-05-27 18:43:10 +03:00
agra
ac60d98f0e ffi M5.A.next.4.0: activate Value.type_tag — opcode + helper + cmp
Wires the dormant `Value.type_tag(TypeId)` variant in interp.zig
so Type values flow through the comptime interpreter as
first-class kind-distinguished entities. No source-language
construction path yet — that's a follow-up. This commit is the
infrastructure foundation.

Audit findings (from interp.zig switch-walk):
- Every `else =>` arm over Value is either already loud
  (`bailDetail` / `error.TypeError`) or a pass-through helper
  (`materializeCtxArg`, `materializeForCall`, `resolveSlotChain`)
  where transit-unchanged is semantically correct for type_tag.
  No new silent paths introduced by activating the variant.
- The three pre-existing `.type_tag => return bailDetail(...)`
  arms (store-at-raw-ptr, deref-non-pointer, unbox-non-aggregate)
  already cover the disallowed paths cleanly.

New plumbing:
- `Op.const_type: TypeId` — dedicated opcode. Never piggybacks
  on `const_int`. Result IR-type is `.any` to signal "untyped
  at runtime" so downstream coercions fail loudly.
- `Builder.constType(tid)` constructor.
- Interp arm emits `Value{ .type_tag = tid }` for the op.
- emit_llvm arm bails loudly + emits an undef-i64 placeholder
  (Type is comptime-only — if a Type ever reached LLVM emit,
  some upstream builder leaked through; the diagnostic + LLVM
  verifier downstream surface the offending site).
- `print.zig` arm prints `const type(<typeName>)`.
- `Value.asTypeId() ?TypeId` helper — the kind-honest accessor
  for Type values. asInt/asFloat/asBool/asString continue to
  return null for `.type_tag` (no silent coercion).
- `evalCmp` arm for `.type_tag, .type_tag` — TypeId equality.
  Mixed `.type_tag` vs `.int` deliberately falls through to
  the typeErrorDetail bail (a Type is not an int).

Tests (src/ir/interp.test.zig):
- `const_type yields type_tag` — confirms the variant is
  produced and that asTypeId/asInt distinguish correctly.
- `type_tag comparison` — exercises cmp_eq on equal and
  unequal pairs, asserts the right bool comes back.

208/208 example tests + `zig build test` green. No user-visible
behaviour change yet — `.type_tag` is constructible from Zig-
side IR builders but no sx-level syntax produces it. Next slice
wires `$args` lowering (or `$args[i]` in expression position)
to emit `const_type` per pack element.
2026-05-27 18:30:17 +03:00
agra
8b457ffc44 ffi M5.A.next.3b: type_eq + has_impl comptime intrinsics
Step 3 second slice. Adds two reflection builtins used by
pack-fn bodies to branch on type identity / protocol
membership at compile time. type_name already existed
(lower.zig:8693); reused as-is.

  type_eq(T1, T2)   -> bool   structural TypeId equality
  has_impl(P, T)    -> bool   T has a reachable impl for P

Both are wired through `tryConstBoolCondition` so the inline-if
ladder folds them at lower time — `inline if type_eq(...)` /
`inline if has_impl(...)` collapse to a single branch with no
runtime instructions, perfect for guard-based dispatch inside
pack-fn bodies.

`has_impl`'s protocol arg accepts two shapes:
- plain protocol name: `has_impl(Allocator, CAllocator)` →
  walks `protocol_thunk_map["Allocator\x00CAllocator"]`.
- parameterised call: `has_impl(Into(Block), s64)` →
  builds the param_impl_map key `"Into\x00Block\x00s64"`
  and checks containment. The protocol type-args resolve
  through `resolveTypeArg` so type aliases, generics, and
  pack-indexed types all work as protocol args.

`computeHasImpl` is the shared implementation between the
runtime builtin path and the `tryConstBoolCondition` fast
path so both branches stay in sync.

`examples/168-pack-reflection-intrinsics.sx` exercises every
shape:
- type_name for primitive types.
- type_eq with both equal + unequal cases, including pointer
  types (s64 vs *s64).
- inline-if folding type_eq.
- has_impl with a real plain-protocol impl
  (Allocator/CAllocator → true; Allocator/s64 → false).
- has_impl with a user-defined parameterised protocol
  (Wrap(s64)/s32 → true; mismatched target args → false).

208/208 example tests + `zig build test` green.

Caveat: plain-protocol has_impl uses `protocol_thunk_map`
which is lazily populated when an `xx` cast or protocol
dispatch creates the thunks. For a static check before any
dispatch, that could false-negative. Allocator/CAllocator
works in 168 because stdlib's startup uses CAllocator through
the Allocator protocol — the thunks already exist by the time
has_impl runs. A more robust static check (walk fn_ast_map for
"<T_name>.<method>" entries against the protocol's method
list) is deferred to a follow-up if needed.

LSP "undefined variable" warnings on type names in expression
position (s64, *s64, Wrap(s64), etc. passed to type_eq /
has_impl) are cosmetic — sema doesn't know these intrinsics
accept types as args. Tracked separately.
2026-05-27 17:48:39 +03:00
agra
9137f4158d ffi M5.A.next.3a.C: $args[$i] in fn-pointer type literals
Adds `resolveFunctionTypeWithBindings` so `function_type_expr`
in a binding-aware context — local var annotations, return
types, nested type expressions — recursively resolves through
the active pack bindings. Without this, the fall-through to
`type_bridge.resolveAstType` lost pack context and the new
`pack_index_type_expr` arm spammed the "outside pack-aware
context" diagnostic (the function still worked by accident
thanks to the `.s64` fallback).

Plumbing:
- `resolveTypeWithBindings` adds a `function_type_expr` case
  in both the bindings-active branch and the fallthrough
  switch (the same shape as `closure_type_expr`).
- `resolveFunctionTypeWithBindings` recursively resolves each
  param + return type with bindings, then calls
  `functionTypeCC` with the AST's calling convention.

`examples/167-pack-type-fnptr.sx` exercises the pattern step
5's trampoline needs:
  fp : (*void, $args[0]) -> $args[1] = double_s64;
  return fp(null, args[0]);
Output: 14 (= 7*2 via the typed fn-pointer).

207/207 example tests + `zig build test` green.
2026-05-27 17:26:27 +03:00
agra
3df58febb6 ffi M5.A.next.3a.B: $args[$i] in type positions — parser + resolver
Step 3 first slice. `$<pack>[<int_literal>]` now parses in
every type position and resolves against the active pack
binding (`pack_arg_types` map set up by `monomorphizePackFn`).

Plumbing:

- src/ast.zig: new `PackIndexTypeExpr { pack_name, index }`
  AST node + `pack_index_type_expr` variant in `Data`.
- src/parser.zig: in `parseTypeExpr`'s `$<ident>` arm, peek
  for `[`. If found, parse a non-negative `int_literal` index
  followed by `]` and emit a `pack_index_type_expr` node.
  Plain `$T` / `$T/Eq` paths unchanged.
- src/ir/lower.zig::resolveTypeWithBindings: handles
  `pack_index_type_expr` first — looks up the pack name in
  `pack_arg_types`, returns `arg_tys[index]` when in range.
  OOB and "no active pack binding" cases emit focused
  diagnostics at the node span.
- src/ir/type_bridge.zig::resolveAstType: handles the same
  node but falls back to `.s64` with a stderr note — the bare
  type_bridge has no access to lowering state. Pack-aware
  callers route through `resolveTypeWithBindings`.
- src/sema.zig: adds `pack_index_type_expr` to the no-op
  arms in `analyzeNode` and `findNodeAtOffset` so the sema
  pass doesn't reject the new variant.

Tests:

- examples/165-pack-type-position.sx (lock-in from 69dcee8)
  flips from parse error to "42 first". Exercises both a
  return-type position (-> $args[0]) AND a local-var
  annotation (second : $args[1] = args[1]); two
  heterogeneous call shapes confirm distinct monos pick
  distinct concrete types per pack index.
- examples/166-pack-type-position-three.sx — three-element
  pack with $args[2] (third element) as return type. Three
  call shapes: (s64,s64,string), (bool,f64,s64),
  (string,string,bool). Prints "third 99 false".

Out of scope (deferred):
- $args[$i] where $i is a comptime-bound expression (only
  literal int supported in this slice).
- $args[$i] in fn-pointer type LITERALS (works for named
  decls but nested fn type expressions need an audit).
- $args[$i] in struct field types.

206/206 example tests + `zig build test` green.
2026-05-27 17:23:47 +03:00
agra
248d6e669c ffi issue-0046 fix: save/restore outer state in createComptimeFunction
`createComptimeFunction` wraps a comptime expression into a
fresh fn that the interp executes in isolation. The wrapper
must not inherit the enclosing call's lowering state — any
leaked slot, binding, or scope flag corrupts the wrapper's
own lowering.

Pre-fix, only `func` / `current_block` / `inst_counter` /
`scope` / `current_ctx_ref` were saved. Specifically NOT
saved:

- `inline_return_target` — set by `lowerComptimeCall` for an
  outer comptime body with `return X;`. The wrapper's body
  was lowering through this slot, routing the wrapper's
  `ret` into a basic block from a different function.
- `pack_arg_nodes`, `pack_param_count`, `pack_arg_types` —
  active during a pack-fn mono's body lowering. (Pack-fn
  face of 0046 was already fixed by step 2b moving pack-fn
  calls off the inline path; these saves close a latent
  cross-contamination if any future pack-mono body invokes
  the comptime interp.)
- `comptime_param_nodes` — active during an outer
  `lowerComptimeCall` to bind `$fmt`-style substitutions.
- `block_terminated`, `target_type`, `func_defer_base` — fn-
  local flags that the wrapper's lowering needs fresh.

All eight now save/restore in `createComptimeFunction`. The
wrapper runs in a clean state.

`examples/issue-0046.sx` flips from the
non-deterministic interp panic to "inside\n" + "n=42\n".

204/204 example tests + `zig build test` green. Issue file
marked FIXED with a pointer to the regression test.
2026-05-27 16:57:19 +03:00
agra
159f898ffe ffi M5.A.next.2b.fu1.B: mixed comptime+pack — mono with comptime values folded into mangle
Fixes follow-up #1 from step 2b. Pack-fns can now mix non-pack
comptime params with the trailing pack:

  tagged :: ($tag: s32, ..$args) -> s64 {
      return tag * 100 + args.len;
  }

`isPackFn` relaxed to "exactly one trailing pack + any number
of non-pack comptime params". The mono path takes over.

Plumbing in src/ir/lower.zig:

- `lowerPackFnCall` walks fd.params + call_node.args in lockstep:
  comptime non-pack args fold into the mangle (`__ct_<value>`
  segments); non-comptime non-pack args contribute to the
  runtime arg-type list; remaining call args populate the pack
  expansion.
- `appendComptimeValueMangle` mangles int / bool / float /
  string literals stably. Strings hash to keep the symbol short.
  Distinct comptime values get distinct monos.
- `monomorphizePackFn` takes `call_node` so it can read comptime
  call args. Skips comptime non-pack params when building the
  runtime IR signature. Binds each comptime non-pack param both
  as a `comptime_param_nodes` entry (for `#insert`) AND as a
  runtime local via alloca+store (for bare-name body access).

`examples/164-pack-mixed-comptime.sx` flips from "unresolved
'tag'" to `703` / `900`. Two calls of `tagged` with
different comptime tags get distinct monos
(`tagged__ct_7__pack_...` and `tagged__ct_9__pack`).

This is the load-bearing prerequisite for step 6 of the plan
(stdlib `print` / `format` refactor to `(\$fmt, ..\$args)`).

Out of scope:
- Non-literal comptime args. `appendComptimeValueMangle`
  degrades them to `?` (so two distinct non-literal expressions
  in the same call slot would collide). Acceptable since
  literal args are the only common case; non-literal would need
  comptime evaluation to determine the value.

203/203 example tests + `zig build test` green.
2026-05-27 16:47:52 +03:00
agra
d30d566397 ffi M5.A.next.2b.fu34.B: pack-mono materialises []Any slice for bare args
Fixes follow-ups #3 (bare `args` reference) and #4
(`args[<runtime_int>]`) from step 2b. The pack-mono now
materialises an `[]Any` slice value for the pack name at body
entry: each pack-param slot is loaded, boxed via `boxAny`, and
stored into a stack [N x Any] array; the slice {data_ptr, len}
binds to the pack name in scope.

Plumbing in src/ir/lower.zig:

- `materialisePackSlice(scope, pack_name, slot_refs, arg_types)`
  — new helper that emits the array alloca + box+store loop +
  slice alloca + bind. Empty-pack case (N == 0) emits {null, 0}
  directly.
- `monomorphizePackFn` captures the pack-param slot Refs as
  they bind, then calls `materialisePackSlice` after binding so
  the slice load can pull each param value.

After: `args` (bare) resolves as `[]Any` and forwards to
slice-typed helpers; `args[<runtime_int>]` lowers through the
standard slice-indexing path, element type `Any`. Per-position
type info is lost via Any boxing — that is the inherent cost
of treating a heterogeneous pack as a uniform value. Literal-
indexed access still routes through `packArgNodeAt` and keeps
the concrete per-position types.

`examples/162-pack-bare-args.sx` flips from "unresolved 'args'"
to `3` (forwarded to `log_count(items: []Any)` which returns
`items.len`).

`examples/163-pack-runtime-index.sx` flips from the LLVM
verifier crash to `4` (while-loop over `args.len`, indexing
each `args[i]` runtime).

202/202 example tests + `zig build test` green.
2026-05-27 16:41:28 +03:00
agra
2e0b97aaa5 ffi M5.A.next.2b.fu2.C: heterogeneous pack ret + OOB diagnostic
Two follow-on fixes for follow-up #2 (generic pack-fn return).

(1) `pack_arg_types` — a new type-only pack binding consulted by
`inferExprType` for `<pack_name>[<int_literal>]`. The earlier
`pack_arg_nodes`-via-synthesized-idents path lost the type
during return-type inference because the synthesized idents
("__pack_args_0" etc.) only resolve once the mono scope is set
up — but the inference runs BEFORE scope setup. Now
`monomorphizePackFn` installs `pack_arg_types[<pack>] =
arg_types` alongside the existing nodes/count maps, and
`inferExprType` consults it directly.

`foo(..$args) -> $R => args[2]` called as `foo(42, 3.2, "hello")`
now correctly returns "hello" (string) — the third element-
typed pick threads through inference to the mono ret_ty.

(2) `diagPackIndexOOB` — focused diagnostic for `args[<lit>]`
where the literal exceeds the pack arity. Pre-fix the
substitution returned null and the standard slice-indexing
fall-through emitted "unresolved args" — burying the real
cause. Now: "pack index 2 out of bounds: 'args' has 1
element" at the index span.

Tests:
- `examples/160-pack-hetero-ret.sx` — generic `$R` with non-
  zeroth heterogeneous pick (returns "hello").
- `examples/161-pack-index-oob.sx` — call passes 1 arg but
  body indexes args[2]; locks in the OOB diagnostic shape.

200/200 example tests + `zig build test` green.
2026-05-27 16:34:26 +03:00
agra
c917f92509 ffi M5.A.next.2b.fu2.B: generic pack-fn return — infer ret_ty from body
Fix for follow-up #2 from step 2b. When a pack-fn declares
`(..\$args) -> \$R` (return type a generic name), the mono now
infers ret_ty from the body's first explicit `return X;` or
falls back to the tail expression of an arrow-form body.

Plumbing in src/ir/lower.zig:

- `inferPackBodyReturnType(body)` walks the body via the
  existing `findReturnValueType` helper (return stmts) and
  falls through to `inferExprType` on the tail expression for
  arrow-form / tail-expr bodies.
- `monomorphizePackFn` now pre-installs `pack_arg_nodes` and
  `pack_param_count` BEFORE resolving the return type so the
  inference can substitute `args[<lit>]` to call-site arg
  AST nodes during type lookup.
- Generic-ret detection: `fd.return_type` AST node is a
  `type_expr` with `is_generic = true`. Concrete returns stay
  on the standard `resolveReturnType` path.

`examples/159-pack-generic-ret.sx` flips from `0 0` (silent-
zero coercion through opaque struct ret_ty) to `42 99`.

198/198 example tests + `zig build test` green.
2026-05-27 16:28:52 +03:00
agra
79896188eb ffi M5.A.next.2b: per-call-shape monomorphisation for pack-fns
Pack-fns (`isPackFn(fd) == true` — last param `is_variadic AND
is_comptime`, no other comptime params) now emit ONE
monomorphised function per unique call-site signature. Repeat
calls with the same arg-type tuple share the mono; distinct
shapes get distinct symbols. Pre-2b each call inlined a fresh
body copy into the caller's basic block; IR size grew linearly
in call sites.

Plumbing in `src/ir/lower.zig`:

- `isPackFn(fd)` — true when the only comptime param is a
  trailing pack. Mixed `($fmt, ..$args)` shapes stay on the
  inline `lowerComptimeCall` path (different substitution
  mechanism for the comptime non-pack param; deferred).
- `lowerPackFnCall(fd, call_node)`:
  - Builds a mangled name `<fn_name>__pack__<arg_types>` from
    call-site `inferExprType` results. Distinct shapes get
    distinct symbols.
  - Cache-checks `lowered_functions`; calls
    `monomorphizePackFn` on miss.
  - Lowers call args, then re-fetches the func pointer (the
    fetch BEFORE arg lowering would invalidate after any
    transitively-triggered module.functions.items realloc),
    prepends ctx if needed, coerces, emits direct call.
- `monomorphizePackFn(fd, mangled, arg_types)`:
  - Mirrors `monomorphizeFunction` for the standard fn build:
    save state, build param list (ctx + fixed prefix + N pack
    params with synthesised names `__pack_<name>_<i>`),
    `beginFunction`, entry block, bind params to scope.
  - Installs `pack_arg_nodes[<name>]` with synthesised AST
    identifier nodes pointing at the pack-param slots so the
    body's `args[<int_literal>]` substitutes through the
    existing 2a.B mechanism — substitution resolves to the
    mono's own param slot loads.
  - Installs `pack_param_count[<name>] = N` so the body's
    `args.len` resolves to a compile-time constant via a new
    intercept in `lowerFieldAccess` (and the parallel arm in
    `inferExprType`).
  - Lowers the body with `inline_return_target = null` so
    `return X;` emits a real `ret X` instead of the inline-slot
    routing — the mono is a real fn now.
- Routed at three call sites: each `if (hasComptimeParams(fd))
  { return self.lowerComptimeCall(...); }` now first checks
  `isPackFn(fd)` and routes to `lowerPackFnCall` when true.

Lifetime gotcha caught and fixed: `params.items` is stored by
reference in `Function.init` (no copy), so the local
`ArrayList(Function.Param)` must NOT be deinit'd in
`monomorphizePackFn` — matches the leak convention already used
by `monomorphizeFunction`.

`examples/158-pack-mono-dedup.sx` confirms the dedup
end-to-end: `count(), count(1), count(2), count(1,2,3),
count("x", true)` produces `0 1 1 3 2` at runtime AND emits
exactly 4 monos in IR (`count__pack`, `count__pack_s64`,
`count__pack_s64_s64_s64`, `count__pack_string_bool`) — the
two s64 calls share. `args.len` resolves to the comptime
constant N inside each mono.

`examples/156-pack-typed-index.sx` and
`examples/157-pack-if-return.sx` continue to pass unchanged.

Out of scope:
- Mixed `$fmt + ..$args` shapes (stays on inline path).
- Generic `$R` return types (concrete returns only).
- Bare `args` reference (passing the slice as a whole).
- `args[<runtime_int>]` (non-literal index).

197/197 example tests + `zig build test` green.
2026-05-27 15:44:05 +03:00
agra
e6d6903708 ffi M5.A.next.2a.D: inline-return uses CFG terminator, not block_terminated
Fixes the regression locked in by 2a.C (commit 6b7a66b).
issue-0045's original fix set `block_terminated = true` after
each inline `return X;` to skip dead code in the inlined body.
But the flag leaked past structured control flow — an `if cond
{ return X; }` whose merge block continued to subsequent
statements would short-circuit the trailing code at the
`lowerBlockValue` loop's `if (self.block_terminated) return
null;` check.

Switched to the classical SSA "return-done block" shape:

- `InlineReturnInfo` carries a third field `done_bb: BlockId`
  — a fresh basic block allocated by `lowerComptimeCall` per
  comptime-call instance.
- `lowerReturn`'s inline path stores into the slot, drains
  defers, and emits `br done_bb`. The basic block's terminator
  is what carries the "no fall-through" signal; the
  `block_terminated` flag is no longer touched.
- `lowerComptimeCall` allocates the slot + done_bb, lowers the
  body, then switches to done_bb and loads the slot. Tail-
  expression bodies that fall through (rare when has_return is
  true) get a synthetic store + br so the CFG is well-formed.

For `if cond { return 42; }; return -1;`:
- cond=true: then's `return 42` stores 42, br done_bb. Merge
  block has only the false predecessor, doesn't run the
  trailing return. Load done_bb → 42.
- cond=false: condBr skips to merge. Merge runs `return -1;`
  → store -1, br done_bb. Load → -1.

`examples/157-pack-if-return.sx` flips from `8354116000` (the
uninitialised slot load on the false path) to `-1`. A
three-way `classify(..$args)` smoke confirms multi-path
inline-return works for any of the three branches.

Dead-code-after-return inside the inlined body still trips the
LLVM verifier (same shape as a regular `return X; print("dead");`
which also crashes today). Acceptable consistency — user code
shouldn't write unreachable code in either context.

196/196 example tests + `zig build test` green.
2026-05-27 14:55:25 +03:00
agra
cd367847a9 ffi M5.A.next.2a.B: pack typed indexing — args[$i] substitutes call arg
Pack-fn bodies that index the pack via `args[<int_literal>]`
now resolve to the i-th call-site argument's lowered value
directly, propagating the call arg's concrete type instead
of the boxed `Any` that the `[]Any` slice path returns.

New plumbing in `src/ir/lower.zig`:

- `pack_arg_nodes: ?std.StringHashMap([]const *const Node)` on
  Lowering. Maps a pack param name (e.g. "args") to the slice
  of call-site arg AST nodes.
- `lowerComptimeCall` populates the map when the variadic
  param is heterogeneous (`is_variadic AND is_comptime`, i.e.
  the `..$args` form). Plain `args: ..Any` keeps the existing
  `[]Any` slice path so stdlib's `format`/`print` continue
  unchanged. The map is saved/restored across nested calls
  mirroring `comptime_param_nodes`.
- `packArgNodeAt(ie)` returns the call-arg node when an
  index_expr matches `<pack_name>[<comptime_int_literal>]`
  with the index in range; null otherwise (fall through to
  standard slice indexing for runtime indices or non-pack
  bases).
- `lowerIndexExpr` checks `packArgNodeAt` first; on a hit it
  lowers the call arg node directly. `inferExprType`'s
  `index_expr` arm does the parallel check so AST-level type
  inference (e.g., for field-access type checking) sees the
  concrete call-arg type.

`examples/156-pack-typed-index.sx` flips from
"field 'x' not found on type 'Any'" to `7` — `args[0].x` now
resolves through the concrete `Point` type instead of Any.

Out of scope (deferred): non-literal comptime indices
(`args[$i]` where `$i` is an arbitrary comptime expression);
`$args[$i]` in type positions (step 3); per-mono mangling
(monomorphisation stays inline-only).

195/195 example tests + `zig build test` green.
2026-05-27 13:55:19 +03:00
agra
9e78790ebf ffi issue-0045 fix: inline-return slot for comptime-call bodies
`lowerComptimeCall` now scans the body for `return` statements
via `fnBodyHasReturn`. When found, it allocates a stack slot
typed to the fn's return type and installs it as
`self.inline_return_target` before lowering the body.

`lowerReturn` checks `inline_return_target` first:
- If set, it stores the coerced return value into the slot,
  drains pending defers, sets `block_terminated = true`, and
  returns without emitting a `ret` into the caller's basic
  block.
- Otherwise it emits the standard `ret` as before.

After the body lowers, the inliner either returns the
tail-expression value (existing fast path — bodies with no
`return` skip the slot entirely) or loads the slot when
`block_terminated` is set.

Why the bug was invisible until now: `format`/`print` and
every other stdlib comptime fn use arrow form (`=> expr`) or
`#insert`-only bodies — no `return` statement, no path through
`lowerReturn`. Step 1.b of the pack feature made `..$args`
parseable; the natural smoke test
`foo :: (..$args) -> s64 { return 42; }` was the first
comptime-fn body to take the `return`-with-trailing-statements
path, surfacing the LLVM verifier crash.

`examples/issue-0045.sx` flips from the lock-in failure to
`42`. 194/194 example tests + `zig build test` green.
2026-05-27 13:21:23 +03:00
agra
08feb6040b ffi M5.A.next.1d.B: pack impl matching — bind $args + $R per call
Pack-shaped impls (`impl P(...) for Closure(..$args) -> $R`) now
match concrete closure sources at xx resolution time. Concrete
impls keep their priority — pack matching only fires on a
concrete-key miss in `param_impl_map`.

New plumbing in src/ir/lower.zig:

- `PackParamImplEntry` carries the pack-shaped source TypeId plus
  the pack-var and ret-var names extracted from the impl AST's
  `target_type_expr`. `registerParamImpl` detects pack-shaped
  sources via `pack_start != null` on the resolved closure type
  and additionally registers in a new `param_impl_pack_map`
  keyed by `"Proto\x00<arg_mangled>"` (no source suffix).

- `tryUserConversion` re-shapes the concrete lookup so the pack
  path runs on miss. `tryPackImplMatch` walks the pack entries,
  verifies the source's fixed prefix matches the impl's prefix,
  binds the pack-var to the source's tail param TypeIds, binds
  the ret-var (when the impl's return is generic) to the source
  return, and monomorphises the convert method. Mangled name
  stays keyed on the concrete source so distinct call shapes
  monomorphise separately.

- `pack_bindings: ?StringHashMap([]const TypeId)` is saved/
  restored around monomorphisation, mirroring `type_bindings`.

- `resolveClosureTypeWithBindings` handles the closure_type_expr
  node during type resolution: when the closure carries a
  `pack_name` AND `pack_bindings` has a binding for it, the
  bound TypeIds are appended after the fixed prefix and the
  result is a concrete (non-pack) closure type — so the impl
  body's `self: Closure(..$args) -> $R` substitutes to the
  concrete source closure during monomorphisation. Without an
  active binding, the pack shape is preserved.

`examples/155-pack-impl-match.sx` flips from the
"no Into(Block) for cl_s32_bool__bool" lock-in diagnostic to
"pack impl match ok": one user-declared
`impl Into(Block) for Closure(..$args) -> $R` covers a
`Closure(s32, bool) -> bool` source that stdlib has no
hand-rolled impl for. Constructed Block isn't invoked
(invoke=null) — the test exercises only the matching +
monomorphisation, not the trampoline (step 5 of the plan).

Existing concrete-impl paths unchanged: 95-objc-block-noop,
96-objc-block-multi-arg, and stdlib's hand-rolled
`Into(Block) for Closure(bool) -> void` continue to pass through
the concrete map first. Same-file duplicate pack impls
diagnose at registration; cross-module visibility and
multi-pack-impl specificity stay TODOs (matching the deferred
Phase 5 work on the concrete path).

193/193 example tests + `zig build test` green.
2026-05-27 12:57:45 +03:00
agra
65824494a7 ffi M5.A.next.1c.B: pack type rep — Closure(..$args) parses + interns
`parseTypeExpr`'s `Closure(...)` arm now accepts a trailing
`..$name` (sigil optional) as a variadic-pack marker. Pack must
be terminal — `)` is the only token accepted after the name.
`ClosureTypeExpr` AST gains `pack_name: ?[]const u8` carrying the
identifier so later slices can name the binding.

`FunctionInfo` / `ClosureInfo` in src/ir/types.zig grow a
`pack_start: ?u32 = null` field. `Closure(..$args) -> R` interns
as `params = []`, `pack_start = Some(0)` — distinct from any
concrete `Closure(...) -> R` shape thanks to updated hash/eql
arms. New constructor pair `closureTypePack` /
`functionTypePack` keeps the existing single-shape constructors
unchanged.

`type_bridge.resolveClosureType` calls `closureTypePack` when
`pack_name != null`. The pack starts after the fixed prefix,
so `Closure(Prefix, ..$args)` resolves with `params = [Prefix]`,
`pack_start = Some(1)`.

No semantic effect yet — the signature exists in the type table
but no matching code reads `pack_start`. Step 1d wires impl
matching: `Closure(..$args) -> $R` binds against any concrete
closure source type in `tryUserConversion` / `registerParamImpl`.

`examples/154-pack-type-rep.sx` flips from rejecting-with-error
to positive parse smoke (prints "pack type rep ok").

192/192 example tests + `zig build test` green.
2026-05-27 12:12:16 +03:00
agra
07f25689ff ffi M5.A revert: drop compiler synthesis, require explicit Into(Block) impls
Reconsidered the M5.A.2 cleanup. The compiler-synthesised trampoline
path was hidden behaviour — a user reading their code couldn't tell
how `xx my_closure : Block` worked without reading lower.zig. That's
exactly the kind of magic sx's design has been pushing against.

New design (strict mode):

1. Stdlib's modules/std/objc_block.sx hand-rolls
   `__block_invoke_void` + `Into(Block) for Closure() -> void` and
   the same pair for `Closure(bool) -> void` (restored from M5.A.2).
   These are readable reference implementations of the bridge ABI.

2. The compiler intercept fires NO synthesis — instead, when
   `tryUserConversion` can't find a reachable `Into(Block)` impl for
   the closure's signature, it emits a focused diagnostic:
     "no `Into(Block) for <Closure-sig>` impl — add a per-signature
      `__block_invoke_<sig>` trampoline + Into impl alongside the
      existing ones in modules/std/objc_block.sx, or declare it in
      your own code"

3. Per-signature declarations live in stdlib (for common signatures)
   or in user code (for app-specific ones). 96-objc-block-multi-arg
   now demonstrates the user-side pattern in-file — it declares its
   own `__block_invoke_void_s32_p` + `Into(Block) for Closure(s32,
   *void) -> void` impl alongside its main().

Net effect:
- Every block bridge is source-visible. No hidden compiler magic.
- Users see exactly how the Apple ABI shape is constructed in sx
  source — stdlib serves as the reference implementation.
- Compiler enforces the discipline: missing impl → clear diagnostic
  pointing at the template.
- Coverage for arbitrary signatures requires conscious user opt-in,
  not silent fallthrough.

Removed from lower.zig: `tryClosureToBlockConversion`,
`emitBlockInvokeTrampoline`, `mangleClosureSigForBlock`,
`mangleTypeForBlock`, and the `block_invoke_trampolines` dedup
state field. Net: the synthesis machinery is gone; only the
detection helper `isClosureToBlockCast` remains, used by the
diagnostic.

190/190 example tests pass; chess on iOS-sim green.
2026-05-27 00:34:26 +03:00
agra
22c087ff35 ffi M5.A: compiler-synthesised __block_invoke_<sig> trampolines
`xx closure : Block` casts now bypass the user-space Into(Block)
protocol path entirely. The compiler intercepts in
`tryUserConversion` BEFORE the Into lookup, detects when src is
`Closure(...)` and dst is `Block`, and emits:

1. A C-ABI trampoline `__block_invoke_<sig>` (deduped per closure
   signature via `block_invoke_trampolines` map). Body matches the
   existing hand-rolled `__block_invoke_void` exactly: load
   block_self struct, extract sx_env (field 5) + sx_fn (field 6),
   call sx_fn(__sx_default_context, sx_env, ...user_args), return.

2. Inline Block-struct construction at the cast site:
   `Block { isa = &_NSConcreteStackBlock, flags=0, reserved=0,
            invoke = &__block_invoke_<sig>,
            descriptor = &__sx_block_descriptor,
            sx_env = closure.env, sx_fn = closure.fn_ptr }`

Signature mangling: compact codes — `v` void, `b` bool, `i` s32,
`q` s64, `f` f32, `d` f64, `c/C/s/S/I/Q` for other ints, `p` for
pointers/aggregates that lower to a machine word. Return first,
then params underscore-joined. `Closure() -> void` mangles to `v`;
`Closure(bool) -> void` mangles to `v_b`.

Loud failures at the cast site:
- `Block` struct missing → "requires #import \"modules/std/objc_block.sx\";"
- `_NSConcreteStackBlock` extern missing → same diagnostic.
- `__sx_block_descriptor` global missing → same.
- `__sx_default_context` missing inside the trampoline emitter →
  compiler-bug diagnostic (the scan pass should always register it).

The existing hand-rolled stdlib impls (`__block_invoke_void`,
`__block_invoke_bool`, the two `Into(Block) for Closure(...)`
impls) are now redundant — the compiler-synthesised trampoline
takes over via the intercept. Next commit (M5.A.2) removes them.

95-objc-block-noop continues to pass; IR shows `__block_invoke_v`
(the synthesised name) replacing the hand-rolled
`__block_invoke_void` at the cast site. 189/189 example tests
pass; chess on iOS-sim green.
2026-05-27 00:23:19 +03:00
agra
fcbd7a4235 ffi M4.B dealloc: release strong/copy property ivars + destroyWeak weak
emitObjcDefinedClassDeallocImp now walks the class's #property fields
BEFORE freeing the state struct. For each:

- assign  → no-op (primitives, no ARC traffic).
- strong  → val = load field; objc_release(val).
- copy    → same as strong (the stored value is a +1 retained copy
            produced by the setter's [val copy]; we release it here).
- weak    → objc_destroyWeak(&field) — unregisters the slot from
            libobjc's side-table so the runtime stops tracking it.

Order matters: property releases happen BEFORE freeing the state
struct (which would invalidate the pointers we need to read), which
happens BEFORE [super dealloc] (which eventually frees the Obj-C
instance's own memory). The full sequence is now:

  %state    = object_getIvar(self, __sx_state_ivar)
  // M4.B (this commit):
  for each strong/copy property P:
      val = load struct_gep(state, P.idx); objc_release(val)
  for each weak property P:
      objc_destroyWeak(struct_gep(state, P.idx))
  // M4.0c (already shipped):
  allocator = load struct_gep(state, 0)
  allocator.dealloc(state)
  object_setIvar(self, ivar, null)
  // M1.2 A.6:
  [super dealloc]   // → objc_msgSendSuper2

ffi-objc-arc-02-strong-property now passes: child held by parent's
strong property gets released when parent deallocates, refcount → 0,
child deallocates, both states freed via tracker. Balanced 2/2.

189/189 example tests pass; chess on iOS-sim green. M4 complete.
2026-05-26 23:10:00 +03:00
agra
c88a293cf4 ffi M4.B getter: weak property reads through objc_loadWeakRetained
emitObjcDefinedPropertyGetter dispatches on objcPropertyKind. The
strong/copy/assign paths keep their bare load. The weak path:

  retained     = objc_loadWeakRetained(field_addr)
  autoreleased = objc_autorelease(retained)
  return autoreleased

`objc_loadWeakRetained` does the race-safe upgrade via libobjc's
side-table: if the target has deinitialized (or is mid-dealloc on
another thread), returns null; otherwise returns the target with
refcount bumped (+1 retained, transferred to caller).

`objc_autorelease` drops the +1 into the current pool so the
caller doesn't need to manually balance — matches Apple's auto-nil
weak-getter contract.

The bare-load weak path (still in place pre-M4.B-getter) worked
for the single-threaded test scenario because the runtime nils the
slot before the load happens. The load-retained version covers the
multi-threaded "between load and use, target deinit's" race that
silent bare-load can't.

189/189 example tests pass; chess on iOS-sim green.
2026-05-26 23:04:00 +03:00
agra
f4faef97dd ffi M4.B setter: emit ARC ops in sx-defined property setters
emitObjcDefinedPropertySetter now dispatches on objcPropertyKind to
emit the right runtime ops per Apple's ARC contract:

- assign  → bare store (primitives, explicitly opted-out object slots).
- strong  → load old; objc_retain(new); store new; objc_release(old).
            Apple's runtime treats release(NULL) as a safe no-op, so
            no explicit null-check on the old value.
- weak    → objc_storeWeak(field_addr, val) — handles first-store
            (init) and re-store (destroy + init) atomically. Registers
            the slot with libobjc's side-table; the runtime auto-nils
            it when the target deallocates.
- copy    → [val copy] (sends `copy` selector — returns retained per
            the NSCopying contract); load old; store the copied
            instance; release old.

Side-effect on the weak path: even with the bare-load getter still in
place (loaded directly from the slot), weak reads work because Apple's
runtime side-table-nils the slot at target dealloc. The getter
improvement via objc_loadWeakRetained is the next commit and is
needed for race-safe reads (between load and use, the target could
deinit on another thread); for the single-threaded test scenarios
the bare load is sufficient.

ffi-objc-arc-02-strong-property advances from "child dealloc'd at
midpoint" to "unbalanced; alloc=2 dealloc=1" — strong setter now
retains, but the M4.B-dealloc cleanup hasn't landed so the child
held by the property isn't released when the parent deallocates.
Final commit (M4.B dealloc) closes the loop.

ffi-objc-arc-03-weak-property turns fully green: storeWeak +
auto-nil side-table do the work.

189/189 example tests pass; chess on iOS-sim green.
2026-05-26 23:02:08 +03:00
agra
5c1d00a877 ffi M4.B helpers: objcPropertyKind + ARC runtime decls + xfail tests
Three pieces, no behavior change yet:

1. `ObjcPropertyKind` enum (strong/weak/copy/assign) + `objcPropertyKind`
   helper in lower.zig. Reads `field.property_modifiers`, applies the
   default rule (`*<ObjC-class>` → strong; primitives → assign), and
   emits loud diagnostics for the silent-error budget:
   - unknown modifier name (typo) → "expected one of: strong, weak, copy, ..."
   - conflicting modifiers (e.g. `strong,weak`) → "mutually exclusive"
   - `weak` on non-object slot → "requires a pointer-to-Obj-C-class type"
   - `copy` on non-object slot → same
   - `strong` (default or explicit) on `*void` → "ambiguous: specify
     #property(strong|weak|copy|assign) explicitly"
   Called from `emitObjcDefinedClassPropertyImps` for validation; the
   returned kind isn't wired into setter/getter/dealloc yet — that's
   the next three commits.

2. `ensureArcRuntimeDecls` lazily declares libobjc's ARC helpers:
   objc_retain, objc_release, objc_storeWeak, objc_loadWeakRetained,
   objc_initWeak, objc_destroyWeak. Uses the existing
   `ensureCRuntimeDecl` pattern; idempotent.

3. Fix existing NSObject method names in std/objc.sx — `isEqual_`,
   `isKindOfClass_`, `respondsToSelector_` had trailing underscores
   that the selector mangling turned into double-colon selectors
   (`isEqual::`). Removed the trailing underscore so the selectors
   come out as `isEqual:`, `isKindOfClass:`, `respondsToSelector:`
   as Apple's runtime expects.

4. Two xfail regression tests:
   - ffi-objc-arc-02-strong-property: assigns child to parent's strong
     property, releases the original child reference. Midpoint check:
     child's dealloc should NOT have fired (strong setter retained).
     Pre-M4.B-setter: child dealloc fires immediately → "FAIL: child
     dealloc'd at midpoint" snapshot. Exit code 1.
   - ffi-objc-arc-03-weak-property: assigns target to holder's weak
     property, releases target. Reads holder.target → should be null
     (auto-niled). Pre-M4.B-getter/setter: reads stale pointer →
     "FAIL: weak property didn't auto-nil" snapshot.

These will turn green as M4.B setter (commit 2), getter (commit 3),
and dealloc-cleanup (commit 4) land. Each subsequent commit updates
the snapshot to reflect the now-passing output.

189/189 example tests pass; chess on iOS-sim green.
2026-05-26 22:58:30 +03:00
agra
92ac51445d ffi M4.0c: -dealloc frees state through captured __sx_allocator
The synthesized -dealloc IMP now loads `state->__sx_allocator` (the
slot captured at +alloc time by M4.0a + M4.0b) and dispatches
`allocator.dealloc(state)` through the inline-protocol fn-ptr at
slot 2. Old behaviour was `free(state)` — went straight to libc,
ignoring whatever allocator the instance was constructed with.

After this commit, the per-instance allocator design from M1.2 A.5
is finally end-to-end correct:

  push Context.{ allocator = arena } {
      f := SxFoo.alloc();     ← arena.alloc(STATE_SIZE) + capture
      // ... use f ...
  }
  // refcount → 0 ⇒ -dealloc:
  //   load state->__sx_allocator   = arena
  //   arena.dealloc(state)         ← same allocator round-trips

TrackingAllocator now sees the alloc/dealloc pair; the deferred M1.2
A.5 work is done. Closes the loop on M4.0.

The dealloc IMP passes `__sx_default_context` as the implicit __sx_ctx
when invoking the dealloc fn-ptr — the IMP itself has no caller-side
ctx (it's called by Apple's runtime at refcount-zero), and the
default GPA is the right baseline for any nested allocations the
dealloc body might perform.

Each compiler-internal lookup that "can't fail" (Context type,
__sx_default_context global) emits a loud diagnostic instead of
silent fall-through, per the silent-error budget.

184/184 example tests pass; chess on iOS-sim green.
2026-05-26 22:30:48 +03:00
agra
2bbd63d929 ffi M4.0b: thread context.allocator through sx-defined +alloc
Two converging paths now allocate the state struct via the protocol's
allocator instead of raw malloc:

(1) sx-side `Cls.alloc()`: compiler intercepts in `lowerObjcStaticCall`
    when the receiver is a sx-defined `#objc_class` and the method is
    the niladic `alloc`. Emits the inline alloc-and-init sequence
    using the caller's `current_ctx_ref` as the context — so
    `push Context.{ allocator = my_arena } { let f := SxFoo.alloc(); }`
    honors `my_arena` end-to-end. The msgSend dispatch is bypassed
    entirely for this case.

(2) Obj-C-runtime `[Cls alloc]` (Info.plist principal class, NSCoder,
    UIKit reflection): the synthesized `+alloc` IMP shim reads
    `__sx_default_context.allocator` and calls into the same shared
    helper. The IMP has `has_implicit_ctx = false` and runs with no
    caller-side context — the default GPA is the right policy choice
    for "everything Apple's runtime instantiates".

Shared helper `emitObjcDefinedAllocAndInit(fcd, cls_ref, ctx_addr)`
does the work: `class_createInstance` → `ctx.allocator.alloc(STATE_SIZE)`
via the inline-protocol fn-ptr → memset 0 → store allocator at
state[0] (the M4.0a slot, captured for -dealloc's later use) →
`object_setIvar(instance, __sx_state_ivar, state)`. Loud failures
on missing globals via the diagnostics system.

The sx-side interception must explicitly bitcast the
`class_createInstance` result from `*void` to the method's declared
return type (`*<Cls>` or `?*<Cls>`). lowerVarDecl reads the Ref's IR
type when no type annotation is present, and coerceToType is a
no-op for ptr→ptr — without the bitcast, `let f := SxFoo.alloc();`
binds `f` at `*void` and downstream `f.class` / `f.method()` fails
to find anything.

-dealloc still uses `free(state)` (M4.0c rewrites it). 184/184 tests
pass; chess on iOS-sim green.
2026-05-26 22:27:33 +03:00
agra
8d7164f45f ffi M4.0a: prepend __sx_allocator to sx-defined-class state struct
State struct for an sx-defined `#objc_class` now leads with an
Allocator field at index 0 — captured at +alloc time, read by
-dealloc to free the state through the same allocator. User fields
shift to index 1+; the existing by-name lookups in
emitObjcDefinedClassPropertyImps + lookupObjcDefinedStateFieldOnPointer
naturally resolve them at the new indices.

This step is the layout change only; the +alloc IMP still mallocs
(M4.0b will rewrite it to thread context.allocator through), and
-dealloc still uses free() (M4.0c). The field is allocated but
uninitialised; nobody reads it yet.

Storage type comes from `Context.fields[0].ty` via the new
`objcStateAllocatorType` helper — same Allocator value-shape the
implicit context machinery has used all along. If Context isn't
registered (early-init paths), the helper falls back to omitting
the field rather than synthesising a half-broken layout.

IR snapshot for 142-objc-class-method-lowering updated to reflect
the new struct shape and the +24-byte state allocation. Chess on
iOS-sim green; 184/184 example tests pass.
2026-05-26 22:07:56 +03:00
agra
a923b6f6f0 ffi fix: route foreign-class UFCS arg target_types through extends chain
For UFCS dispatch on foreign-class receivers (`#foreign #objc_class`
aliases), `resolveCallParamTypes` was returning an empty slice — both
`resolveFuncByName(qualified)` and `fn_ast_map.get(qualified)` miss
for `#foreign` methods (they live in `foreign_class_map`, not the
regular fn maps). With `param_types` empty, the per-arg `target_type`
assignment in `lowerCall` was skipped, leaving `self.target_type` as
whatever it held on entry — usually the enclosing function's return
type. Inside a `-> BOOL` method, `xx ptr` then lowered with target
type `i8`: `ptrtoint ptr to i64` → `trunc i64 to i8`, sending the low
byte of the pointer through.

Symptom: chess on iOS-sim crashed in
`-[NSNotificationCenter addObserver:selector:name:object:]` with
`observer = 0xC0` (low byte of the SxAppDelegate receiver) when the
AppDelegate method's first param was renamed to anything other than
`self`. The original session diagnosed it as a `self`-vs-`this`
hardcoding in `lower.zig`, but those hardcoded `"self"` strings are
all on compiler-synthesized parameters (init scopes, JNI stubs,
property IMPs, dealloc IMPs) — not the user-facing #objc_class body
params. The bug was in arg-type resolution.

Fix walks `foreign_class_map` + `findForeignMethodInChain` to recover
the declared param types (skipping the implicit `*Self` for instance
methods). Regression test `examples/issue-0044.sx` exercises the
BOOL-return + foreign-class arg shape; pre-fix the receiver round-trip
prints WRONG, post-fix it prints ok.
2026-05-26 16:42:21 +03:00
agra
f75923af00 uikit: type UIKitPlatform fields properly + handle optional in Obj-C encoding
The UIKitPlatform struct had a string of '*void = null; // UIWindow*'
fields — the type lived in a comment, every callsite had to 'xx'-cast
back to the real type. Migrated to the real foreign-class pointer
types now that M3 declared all the relevant '#objc_class' aliases:

  window:       ?*UIWindow
  root_vc:      ?*UIViewController
  gl_view:      ?*UIView         (SxGLView OR SxMetalView — both extend UIView)
  gl_layer:     ?*CALayer        (CAEAGLLayer OR CAMetalLayer)
  gl_ctx:       ?*EAGLContext
  display_link: ?*CADisplayLink

Each field is wrapped in '?' since the platform may not have set
it yet (gl_ctx is null in metal mode, display_link is null before
the first frame, etc.).

SxSceneDelegate's window getter/setter now take/return '?*UIWindow'
instead of '*void' so calling code doesn't need an xx-cast.

Required fix in objcTypeEncodingFromSignature: '?T' (optional) was
bailing with 'type kind not yet supported'. Apple's runtime treats
nullability as 'pointer may be null' — the wire encoding is the
same as T. Recursive unwrap handles ?*UIView → '@', ?*CADisplayLink
→ '@', etc.

Chess on iOS-sim: board renders, full pipeline intact. 183 tests
+ zig build test green.
2026-05-26 07:51:12 +03:00
agra
066840d9e0 ffi M3.2: SxSceneDelegate migrated + #implements protocol conformance
Migrates SxSceneDelegate from the hand-rolled
objc_allocateClassPair + class_addMethod + class_addProtocol
sequence to the declarative form:

  SxSceneDelegate :: #objc_class("SxSceneDelegate") {
      #extends UIResponder;
      #implements UISceneDelegate;
      #implements UIWindowSceneDelegate;

      scene_willConnectToSession_options :: (self, scene, session, options) { ... }
      window    :: (self) -> *void { ... }
      setWindow :: (self, w) { ... }
  }

emit_llvm now honors '#implements' in the class-pair init
constructor — for each #implements ProtocolAlias on the cache
entry's AST, emit before objc_registerClassPair:

  proto = objc_getProtocol("ProtocolName")
  class_addProtocol(cls, proto)

iOS checks 'class_conformsToProtocol' when instantiating scene
delegates; without the conformance the runtime silently rejects
the class and a default scene with no delegate gets created
instead. The protocol-getter returns null on dead-strip /
runtime mismatch (rare but possible) — the runtime treats
class_addProtocol(cls, null) as a no-op, so no explicit null
check needed.

Method bodies forward to the existing legacy free IMP functions
(uikit_scene_will_connect, uikit_window_getter,
uikit_window_setter) so we don't have to inline the scene-
connect setup logic (~80 lines).

uikit_register_classes is now tiny — just the two remaining
view-class helpers (M3.3 SxGLView + M3.4 SxMetalView). M3.5
deletes the function entirely once those land.

Chess on iOS-sim: board renders, scene delegate fires, touch
events route correctly. 183 example tests + zig build test
green.
2026-05-26 07:37:14 +03:00
agra
66f84f67b8 ffi M3.1 + M1.2 A.3 refactor: self=Obj-C id, self.field via ivar; SxAppDelegate migrated
Two coupled changes that unblock the uikit_register_classes
migration:

1) M1.2 A.3 — body's 'self' is the Obj-C id (opaque), NOT the
   state struct. Matches Apple's ObjC semantics where 'self' IS
   the object. Cocoa idiom 'xx self → id' works at runtime calls
   (addObserver:, etc.); previously the trampoline replaced
   'self' with the state-struct pointer, breaking any runtime
   call that expected an id.

   '*Self' substitution in resolveTypeWithBindings now points at
   foreignClassStructType(fcd) — the opaque class stub — instead
   of objcDefinedStateStructType(fcd).

   'self.field' access on a sx-defined class instance field is
   rewritten by lowerFieldAccess to go through the __sx_state
   ivar:
     state = object_getIvar(self, load(__<Cls>_state_ivar))
     val   = struct_gep(state, field_idx) → load

   Both read (lowerFieldAccess) and write (lowerAssignment) take
   this path. Compound ops (+=, -=, etc.) are supported via
   storeOrCompound. The lookup is filtered: skip property fields
   (those still go through the M2.2 msgSend getter/setter
   dispatch) and foreign classes (no state).

   New helpers in lower.zig:
   - lookupObjcDefinedStateFieldOnPointer — match check.
   - lowerObjcDefinedStateForObj — emit the object_getIvar +
     ivar-global-load idiom (shared between read + write paths).
   - lowerObjcDefinedStateFieldRead — the load path.

   Also moved the @llvm.global_ctors registration out of the
   sx-defined class-pair init constructor — global_ctors fires
   DURING dyld's framework load, before UIKit registers its Obj-C
   classes. objc_getClass("UIResponder") returned null, super
   was null, objc_registerClassPair crashed. main's entry block
   is post-framework-load but pre-user-code — exactly the right
   window. New helper injectCtorIntoMain.

2) M3.1 — SxAppDelegate migrated to declarative #objc_class.
   uikit_register_classes' hand-rolled objc_allocateClassPair +
   class_addMethod for SxAppDelegate is gone; the compiler
   synthesises the class at module init. The method bodies
   forward to the existing legacy IMP free functions
   (uikit_did_finish_launching, uikit_keyboard_will_change_frame)
   so we don't have to inline 70+ lines of keyboard-frame logic
   right now.

   Also adds UIResponder foreign-class declaration and chains
   UIView / UITextField to it via #extends UIResponder so the
   methods that previously lived on UITextField directly
   (becomeFirstResponder etc.) move to their proper home.

Chess on iOS-sim: board renders, full state intact. 183 example
tests + zig build test green.
2026-05-26 07:32:57 +03:00
agra
ea32f8a27a ffi M2.3: #extends method-resolution chaining + Obj-C parent resolution
When 'obj.method()' is called on a foreign-class pointer and the
method isn't declared on the receiver's class, the compiler walks
the '#extends' chain to find an ancestor that declared it.
Property lookup (M2.2) flows through the same chain walker.

  ParentX :: #foreign #objc_class("...") { foo :: ... }
  ChildX  :: #foreign #objc_class("...") { #extends ParentX; }

  child.foo()   // now resolves — was 'no method foo on ChildX'

Two new helpers in lower.zig:
- findForeignMethodInChain(fcd, name) walks the cache via
  fcd.members[i].extends → foreign_class_map[parent] → ...
  Depth-capped at 16 to break accidental cycles.
- findForeignPropertyInChain(fcd, name) — same shape for fields.

ALSO fixes a latent class-hierarchy bug uncovered while testing
M2.3: emit_llvm was passing the sx alias name to
objc_allocateClassPair(super, ...) rather than the actual Obj-C
runtime class name. For 'SxThing :: #objc_class(...) { #extends
NSObjectBase; }' where 'NSObjectBase' is aliased to "NSObject",
emit_llvm produced 'objc_getClass("NSObjectBase")' → NULL →
'objc_allocateClassPair(NULL, ...)' → SxThing's super-class link
was broken → '[sx_thing hash]' bypassed NSObject and crashed in
the forwarding machinery.

Fix: ObjcDefinedClassEntry gains a 'parent_objc_name' field
pre-resolved by lower.zig's 'resolveObjcParentName' through
foreign_class_map (which has the alias → foreign_path mapping).
emit_llvm just reads the resolved name from the entry.

153-objc-extends-chain.sx exercises both fixes:
  1-level: SxThing → NSObject — t.hash() walks one #extends.
  2-level: SxLeaf  → SxMiddle → NSObject — chained #extends.
Both return real NSObject.hash values from libobjc.

183 example tests pass (+1). zig build test green.
2026-05-26 01:56:25 +03:00
agra
239e7df27c ffi M2.2 (sx-defined): property getter/setter IMPs
Properties on sx-defined #objc_class declarations now synthesize
getter (always) and setter (unless 'readonly') IMPs that GEP into
the hidden state struct and load / store the corresponding field.
The state struct already holds every user-declared field
(objcDefinedStateStructType), so no new layout work — the IMPs
just dispatch a struct_gep + load/store through the __sx_state
ivar.

For each '#property' field on a sx-defined class:

  Getter '__<Cls>_<field>_imp(self, _cmd) -> T':
    state = object_getIvar(self, load(__<Cls>_state_ivar))
    return state.<field>

  Setter '__<Cls>_set<Field>_imp(self, _cmd, val) -> void':
    state = object_getIvar(self, load(__<Cls>_state_ivar))
    state.<field> = val

Both IMPs land in the cache's methods slice (mirroring the
method-IMP wiring from M1.2 A.4b.iii) so emit_llvm's
class_addMethod loop registers them on the class without
special-casing. Selector mangling:
  getter: <field>            (e.g. 'width')
  setter: set<Field>:        (e.g. 'setWidth:')
Type encoding derived from the field's resolved IR TypeId.

'readonly' (the only modifier honored in this slice) skips the
setter emission AND the corresponding method entry — so the
runtime reports the selector as absent. Other modifiers
(strong, weak, copy, assign) parse fine but stay no-ops until
M4.2 wires up ARC ops in the setter body.

152-objc-property-sx-defined.sx round-trips on macOS:
  b.width = 10; b.height = 7;
  read back through getter IMPs.
  area is readonly — class_getInstanceMethod(SxBox, sel(setArea:))
  returns NULL, confirming the setter is absent.

182 example tests pass (+1). zig build test green.
2026-05-26 01:49:31 +03:00
agra
95f13849af ffi M2.2 (first pass): #property directive on foreign-class fields
Adds:
  field: T #property[(modifier, modifier, ...)];

inside #objc_class declarations. For FOREIGN classes (this slice),
'obj.field' and 'obj.field = x' lower as objc_msgSend dispatches —
no struct GEP, no per-field storage on the sx side. The receiver
is opaque and the Obj-C runtime owns the data.

Selector mangling (Apple convention):
  getter: <fieldName>            (e.g. 'count')
  setter: set<FieldName>:        (e.g. 'setBackgroundColor:')

So:
  view.backgroundColor          → [view backgroundColor]
  view.backgroundColor = red    → [view setBackgroundColor:red]

Plumbing:
- New token hash_property + lexer entry + LSP keyword classification.
- ForeignFieldDecl gains 'is_property' + 'property_modifiers' slice;
  the parser captures both. Modifiers are recorded verbatim (strong,
  weak, copy, readonly, getter("name"), ...) — semantic interpretation
  lands with M4.2 ARC wiring.
- lowerFieldAccess: lookupObjcPropertyOnPointer() detects the case
  before the auto-deref / struct-GEP path and dispatches via
  lowerObjcPropertyGetter (objc_msg_send).
- lowerAssignment: same check on the field_access LHS routes to
  lowerObjcPropertySetter (objc_msg_send with set<Field>:).
- inferExprType: 'obj.field' returns the property's declared type
  so chained access / coerced assignment work.

151-objc-property-foreign.sx round-trips:
  inst.tag        → [inst tag]       → reads g_probe_tag → 0
  inst.tag = 42   → [inst setTag:42] → writes g_probe_tag
  inst.tag = -7   → ditto
  Final: 0 -> 42 -> -7  (real Obj-C runtime dispatch).

DEFERRED for M2.2 (later passes):
- Sx-defined property IMPs (synthesized getter/setter trampolines
  reading/writing the state struct).
- Modifier-driven setter behavior: readonly (compile error on
  write), copy (deep-copy), weak (objc_storeWeak), strong/assign
  (Month 4.2 ARC ops).
- getter("name") / setter("name:") selector overrides.

181 example tests pass (+1). zig build test green.
2026-05-26 01:45:21 +03:00
agra
c39c8e15eb ffi M2.1(b): class methods on sx-defined #objc_class
Bodied methods without a '*Self' first param (parser marks
is_static=true) are now registered as Obj-C CLASS methods on
the metaclass.

Each such method gets:
- A synthesized FnDecl + body lowering through the existing
  M1.2 A.2 path.
- A C-ABI trampoline 'emitObjcDefinedClassStaticImp' — same
  shape as the instance trampoline but skips the __sx_state
  ivar read (no instance state) and passes only
  '__sx_default_context' (plus user args) to the sx body.
- An entry in ObjcDefinedMethodEntry with 'is_class=true'.

emit_llvm's class-pair init constructor now computes the
metaclass once up-front (via object_getClass(cls)) and shares
it between the +alloc IMP registration (M1.2 A.5) and the
M2.1(b) class-method registrations. The per-method registration
loop picks the target via 'method.is_class ? metaclass : cls'.

149-objc-class-method-static-imp.sx end-to-end on macOS:

  SxFoo :: #objc_class("SxFoo") {
      answer :: () -> s32 { return 42; }
  }

  // [SxFoo answer] via objc_msgSend → 42
  // class_getClassMethod(SxFoo, sel_answer) → non-null

Still TODO for M2.1: the (a) class-LEVEL constant form
'layerClass :: Class = CAEAGLLayer.class();' — needs parser
extension to recognize 'name :: Type = expr;' inside #objc_class
blocks, plus lazy-init-slot synthesis.

179 example tests pass (+1). zig build test green.
2026-05-25 23:40:51 +03:00
agra
0ac5ba2ccd ffi M1.3: obj.class accessor on Obj-C-class pointers
Adds a special case to lowerFieldAccess: when the field is
literally 'class' and the receiver is a pointer to an Obj-C
(or Obj-C protocol) foreign-class struct, emit
'object_getClass(obj)' instead of falling through to struct GEP.

Returns 'Class' (the M1.1 first-pass alias for *void;
parameterized Class(T) covariance is deferred to M1.1.b).

  f := SxFoo.alloc();
  cls := f.class;                       // → object_getClass(f)
  cls == objc_getClass("SxFoo".ptr);   // ok

New helper isObjcClassPointer(ty) detects 'ptr -> struct in
foreign_class_map under .objc_class / .objc_protocol'. The
check fires BEFORE the auto-deref so the runtime call sees the
opaque Obj-C pointer rather than the load'd struct stub.

148-objc-self-class-accessor.sx exercises both shapes end-to-end
against the macOS runtime: sx-defined class (SxFoo) and foreign
class (NSObject). Round-trips against objc_getClass(name).

178 example tests pass. zig build test green.

This effectively closes Month 1 — M1.0, M1.1 (first pass), M1.2,
M1.3 all done. Remaining: M1.1.b (Class(T) covariance +
instancetype), then Month 2 (declarative sugar).
2026-05-25 23:33:52 +03:00
agra
51277afadf ffi M1.2 A.7: open the dispatch gate — sx-defined class methods callable
Delete the bail at lower.zig:4407 that diagnosed sx-defined Obj-C
class dispatch as 'not yet supported'. Both foreign and
sx-defined '#objc_class' decls now flow through the same
'lowerObjcMethodCall' path — instance methods on sx-defined
classes dispatch via objc_msgSend, and the registered IMP
trampolines (M1.2 A.4b.iii) route to the sx bodies.

The runtime non-Obj-C branch (.swift_class / .swift_struct /
.swift_protocol) keeps its 'not yet supported' diagnostic;
M1.2 only addresses the Obj-C runtimes.

Constructor reorder in emit_llvm: emitObjcDefinedClassInit
runs BEFORE emitObjcClassInit. Otherwise the Phase 3.1
class-cache populator calls objc_getClass("SxFoo") before our
constructor registers the class — cache slot stored null and
'SxFoo.method()' dispatched against a null class pointer.

ffi-objc-defined-class-01-instance.sx (the integration test
from the plan) now runs the full lifecycle on macOS:

  f := SxFoo.alloc()    // synthesized +alloc IMP fires
  f.bump()              // dispatch → IMP trampoline → sx body
  f.bump()              // state persists across calls
  f.bump()
  f.get()               // → 3
  release_fn(f, sel_release)  // synthesized -dealloc fires

The user declares 'alloc :: () -> *SxFoo;' bodyless to give the
synthesized +alloc IMP a typed contract at sx call sites —
same convention as foreign classes today.

M1.2 complete: A.0 A.1 A.2 A.3 A.4 A.4b.i A.4b.ii A.4b.iii
A.5 A.6 A.7. End-to-end class-synthesis foundation works.

177 example tests pass (+1 from the integration test). zig
build test green.
2026-05-25 23:29:55 +03:00
agra
c107aa4e21 ffi M1.2 A.6: synthesized -dealloc IMP + [super dealloc] chain
For every sx-defined #objc_class, emit a C-callconv -dealloc IMP
that runs at refcount-zero. Frees the sx state struct, nils the
ivar, then chains to [super dealloc] so NSObject's runtime
cleanup (object_dispose, associated-object teardown, KVO, etc.)
runs as usual.

  -dealloc IMP (self: id, _cmd: SEL) -> void
      state = object_getIvar(self, load @__<Cls>_state_ivar)
      free(state)                              // free(NULL) is safe
      object_setIvar(self, ivar, NULL)
      sup = alloca { receiver: *void, super_class: *void }
      sup.receiver    = self
      sup.super_class = load @__<Cls>_class
      sel_dealloc = sel_registerName("dealloc")
      objc_msgSendSuper2(&sup, sel_dealloc)
      return

Two new per-class globals:
- '__<Cls>_class' : *void — populated by emit_llvm's
  class-pair init constructor with the freshly-allocated Class
  pointer (after objc_registerClassPair).
- The existing '__<Cls>_state_ivar' is also consulted to find
  the state struct.

The -dealloc IMP is registered on the class itself (instance
method) via class_addMethod with encoding 'v@:'. emit_llvm
ALSO stores cls_val into '__<Cls>_class' so the trampoline
can build the objc_super struct.

internStringConstantGlobal helper added to lower.zig — interns
C strings as [N:0]u8 globals with byte-level aggregate inits.
Used here for the 'dealloc' selector string.

147-objc-class-dealloc-roundtrip.sx verifies end-to-end on
macOS: alloc + release fires the IMP, and a second alloc/release
cycle proves runtime state isn't corrupted. class_getMethod-
Implementation confirms the IMP is registered.

176 example tests pass (+1). zig build test green.

Still gated: sx-side 'obj.method()' calls bail at lower.zig:4407
with the existing diagnostic. A.7 opens the gate — last sub-step
of M1.2.
2026-05-25 23:25:13 +03:00
agra
a1736f3213 ffi M1.2 A.5: synthesized +alloc IMP + ensureCRuntimeDecl helper
For every sx-defined #objc_class, emit a C-callconv +alloc IMP
that the Obj-C runtime calls when '[Cls alloc]' fires (from sx
code, UIKit instantiation, Info.plist principal class, etc.):

  +alloc IMP (cls: Class, _cmd: SEL) -> id
      instance = class_createInstance(cls, 0)
      state    = malloc(STATE_SIZE)
      memset(state, 0, STATE_SIZE)
      object_setIvar(instance, load(@__<Cls>_state_ivar), state)
      return instance

STATE_SIZE = max(typeSizeBytes(state struct), 1) — always at
least one byte so the ivar is never null after +alloc returns.

The IMP is registered on the METACLASS (class methods live there
— every Class object's isa points to the metaclass) in emit_llvm's
class-pair init constructor:

  metaclass = object_getClass(cls)
  sel_alloc = sel_registerName("alloc")
  class_addMethod(metaclass, sel_alloc, alloc_imp, "@@:")

That override wins over NSObject's default +alloc; runtime
instantiations get the __sx_state ivar bound automatically.

Per-instance allocator binding (the plan's full design — store
the Allocator value in the state struct so -dealloc frees through
the same one) is deferred. libc malloc/free is fine for v1; we'll
upgrade once Month 4's autoreleasepool + ARC ops shake out.

REFACTOR: collapsed five duplicate 'get<Name>Fid' helpers and
their cache fields (object_getIvar, object_setIvar,
class_createInstance, malloc, memset) into a single
'ensureCRuntimeDecl(name, params, ret) -> FuncId'. The helper
checks for an existing decl by name first (avoids the
'class_createInstance.1' duplicate-symbol crash when stdlib's
'#foreign' decl is already in the module). One helper instead
of one-per-function = ~150 lines deleted.

object_getIvar / object_setIvar added to stdlib std/objc.sx
so user code can use them too (146 exercises object_getIvar
to verify __sx_state was bound to a non-null state pointer
after +alloc).

146-objc-class-alloc-roundtrip.sx end-to-end against macOS:
'[SxFoo alloc]' returns non-null AND object_getIvar(instance,
__sx_state) returns the state ptr. Real Obj-C runtime, no
mocks.

175 example tests pass (+1). zig build test green.
2026-05-25 23:17:30 +03:00
agra
87572579b4 ffi M1.2 A.4b.iii: class_addMethod wires IMPs to the Obj-C runtime
For each instance method on a sx-defined '#objc_class', the
class-pair init constructor now:

  sel = sel_registerName("selector_string")
  imp = @__<Cls>_<method>_imp                  (M1.2 A.4b.ii)
  class_addMethod(cls, sel, imp, "<encoding>")

before objc_registerClassPair. The IMP trampoline (A.4b.ii)
already bridges C-ABI -> sx body. With registration in place,
'objc_msgSend(obj, sel_bump)' now routes to the trampoline,
which reads __sx_state ivar and forwards to '@<Cls>.<method>'.

To get selector + type-encoding strings out of lower.zig and
into emit_llvm, ObjcDefinedClassEntry gains a 'methods' slice:

  pub const ObjcDefinedMethodEntry = struct {
      sel: []const u8,       // mangled selector (M1.2 A.1's deriveObjcSelector)
      encoding: []const u8,  // type encoding (M1.2 A.1's objcTypeEncodingFromSignature)
      imp_name: []const u8,  // C-callconv trampoline symbol
  };

registerObjcDefinedClassMethods populates this when it declares
each method's body function; Module.setObjcDefinedClassMethods
attaches the slice to the cache entry by name. Static (class-
side) methods are skipped — A.4b only covers instance methods;
class-method hooks like '+layerClass' land in M2.1.

emit_llvm reads entry.methods and emits class_addMethod inside
the per-class init block, before objc_registerClassPair (the
runtime locks the method list at register time on some SDK
versions).

145-objc-class-method-dispatch.sx verifies end-to-end:
class_getMethodImplementation(SxFoo, sel_registerName("bump"))
returns non-null after main starts. Both niladic ('bump') and
single-arg ('add:') selectors checked.

Still gated (A.7): sx-side 'obj.bump()' calls. The dispatch
gate at lower.zig:4407 hasn't opened — A.5 (+alloc) and A.6
(-dealloc) need to land first so the integration test
ffi-objc-defined-class-01-instance.sx (full state round-trip)
can exercise the full lifecycle.

174 example tests pass (+1 from 145). zig build test green.
2026-05-25 22:58:20 +03:00
agra
c0b338eaa4 ffi M1.2 A.4b.ii: emit C-ABI IMP trampolines (dead code pending class_addMethod)
For each bodied instance method on a sx-defined #objc_class,
emit a C-callconv trampoline function '__<Cls>_<method>_imp':

  void __SxFoo_bump_imp(ptr obj, ptr _cmd, ...user_args) {
      ivar  = load @__SxFoo_state_ivar
      state = object_getIvar(obj, ivar)
      call @SxFoo.bump(__sx_default_context, state, ...user_args)
      ret
  }

The trampoline bridges the Obj-C runtime's IMP calling convention
('id self, SEL _cmd, ...args' as C ABI) to the sx body's
default-callconv shape ('__sx_ctx ptr, state ptr, ...user_args').
Implicit context comes from '&__sx_default_context'; the body
keeps its sx-side personality intact and can use 'self.field'
through the substituted state-struct pointer (M1.2 A.2b + A.3).

New helpers in lower.zig:
- 'getObjcObjectGetIvarFid' lazily declares object_getIvar.
- 'emitObjcDefinedClassImps' + 'emitObjcDefinedClassImp' walk the
  cache and synthesise each trampoline.
- 'lookupGlobalIdByName' for finding the per-class ivar handle
  global. Linear scan — same N-is-small rationale as the other
  Obj-C caches.

Dead code at this commit: the trampolines exist in the module
but no class_addMethod call registers them with the runtime.
'objc_msgSend(obj, sel_bump)' would still fall through to the
parent class (NSObject 'doesNotRecognizeSelector:') today.
A.4b.iii wires up class_addMethod in emit_llvm's class-pair-init
constructor — that's when the trampolines come alive.

142's IR snapshot refreshed to show the trampoline.

173 example tests pass. zig build test green.
2026-05-25 22:52:34 +03:00
agra
c2178c062b ffi M1.2 A.4b.i: __sx_state ivar registration
Class-pair init constructor now registers a single hidden ivar
on each sx-defined class:

  class_addIvar(cls, "__sx_state", 8, 3, "^v")

before objc_registerClassPair. After the class is registered,
the constructor calls class_getInstanceVariable to fetch the
runtime Ivar handle and stores it in a per-class global
'__<ClassName>_state_ivar : *void'. Trampolines (A.4b.ii) will
read this global to 'object_getIvar' the state struct pointer.

lower.zig declares the per-class global at scan time
(declareObjcDefinedStateIvarGlobal) so emit_llvm finds it by
name when populating. Encoding '^v' = void* (a generic pointer
— the runtime treats it as opaque storage). log2 alignment = 3
for 8-byte pointer alignment on 64-bit.

144-objc-class-ivar-registration.sx exercises the round-trip:
after main starts, class_getInstanceVariable(SxFoo, "__sx_state")
returns non-null. Runs against the real Obj-C runtime on macOS.

142's IR snapshot refreshed to include the new constructor body
(class_addIvar + class_getInstanceVariable + ivar-global store).

173 example tests pass (+1 from 144). zig build test green.
2026-05-25 22:23:59 +03:00
agra
b98a22e3f9 ffi M1.2 A.4: emitObjcDefinedClassInit class-pair registration
For every sx-defined '#objc_class', emit a module-init constructor
that registers the class with the Obj-C runtime at module load.
Pattern mirrors the Phase 3.1 emitObjcClassInit companion:
'@llvm.global_ctors' + ORC-JIT main injection.

Constructor body, per cache entry:

  super = objc_getClass("<ParentName>")  // default NSObject
  cls   = objc_allocateClassPair(super, "<ClassName>", 0)
  objc_registerClassPair(cls)

Parent is read from the foreign_class_decl's '.extends' member;
absent ⇒ NSObject (matches M1.2 A.0 spec). Class-name strings
go through new emitPrivateCString helper that mirrors the
selector-init / class-init shape.

Two new small helpers extracted while we were here:
- lazyDeclareCRuntime — declare-once extern wrapper for Obj-C
  runtime APIs.
- appendModuleCtor — append-or-create global_ctors + ORC-JIT
  injection, factored out of emitObjcClassInit.

143-objc-class-registration.sx exercises the round-trip on
macOS: after main starts, objc_getClass("SxFoo".ptr) returns
non-null. Runs against the real Obj-C runtime.

142's IR snapshot updated — the constructor + ctors metadata
are now part of the expected shape.

DEFERRED (A.4b): method-IMP registration (class_addMethod with
a C-ABI trampoline that reads __sx_state ivar and calls the sx
body). DEFERRED (A.5+): synthesized +alloc / -dealloc IMPs and
the '__sx_state' ivar setup.

172 example tests pass (+1 from 143). zig build test green.
2026-05-25 22:14:31 +03:00
agra
659cdc2276 ffi M1.2 A.2c + A.3: eager body lowering + self.field via state struct
Adds Pass 4b 'lowerObjcDefinedClassMethods' to lowerRoot: after
scan, walk objc_defined_class_cache and force-lower each bodied
instance method. The Obj-C runtime invokes these via the IMP
pointers wired up in A.4 — no sx-side call path drives lazy
lowering, so we trigger it here. Mirrors the JNI eager-lower
pattern in Pass 5.

Bug fix: lazyLowerFunction has its OWN inline body-lowering
path (separate from lowerFunction) that re-resolves param types
at line 1025. It was running without current_foreign_class set,
so '*Self' fell through to the type_bridge fallback and got
interned as a 0-field struct named 'Self' — body's
'self.counter' GEP'd into '{}' and LLVM verification rejected.
Fix: set current_foreign_class at the top of lazyLowerFunction
via the same lookupObjcDefinedClassForMethod path lowerFunction
uses. Save+restore via defer.

A.3 ('self.field access via the ivar') falls out for free —
'*Self' resolves to '*__SxFooState' so 'self.counter' is a
plain struct field access. IR snapshot in
142-objc-class-method-lowering.ir shows the round-trip:

    define internal void @SxFoo.bump(ptr, ptr self) {
        %gep = getelementptr inbounds { i32 }, ptr %self, 0, 0
        %v = load i32, ptr %gep
        store i32 (%v + 1), ptr %gep
        ret void
    }

171 examples pass (+1 from 142); zig build test green.

Still gated: Obj-C runtime dispatch (A.7) — sx-side
'f.bump()' calls bail at lower.zig:4407 with the existing
diagnostic. IMP-trampoline emission (the C-ABI shim that bridges
'objc_msgSend' → this body) lands in A.4 alongside class-pair
init.
2026-05-25 22:08:23 +03:00
agra
ae1072d415 ffi M1.2 A.2b: register sx-defined #objc_class methods + *Self substitution
Bodied instance methods on a sx-defined '#objc_class("Cls") { ... }'
declaration are now registered in fn_ast_map under '<Cls>.<method>'
and declared in the IR with their *Self params substituted to
the hidden state-struct type (M1.2 A.2a).

registerObjcDefinedClassMethods walks the foreign_class_decl's
members, synthesizes an FnDecl from each ForeignMethodDecl (zipping
params + param_names), and feeds it through declareFunction with
current_foreign_class temporarily pinned so resolveTypeWithBindings
substitutes Self → __SxFooState.

resolveTypeWithBindings now treats type_expr 'Self' as a contextual
alias: when current_foreign_class points to a sx-defined Obj-C
class, the substitution returns objcDefinedStateStructType(fcd).
Other Self contexts (protocols, JNI super, foreign-class member
type resolution) are untouched — the check filters on (!is_foreign
and runtime == .objc_class).

lowerFunction also sets current_foreign_class for the duration of
the body lowering when the name is qualified <Cls>.<method> and
Cls is in objc_defined_class_cache. Save+restore via defer so
nested calls round-trip cleanly.

Verification (manual): 'sx ir' on an sx-defined class shows
'declare void @SxFoo.bump(ptr, ptr)' — two args = implicit
__sx_ctx + the state-struct pointer (correct *Self substitution).
Body emission happens lazily; A.2c will trigger it eagerly so
the IMP trampoline (A.4) can reference it.

170 example tests + zig build test green.
2026-05-25 21:59:23 +03:00
agra
7b98b3ae78 ffi M1.2 A.2a: objcDefinedStateStructType helper
Builds (and interns) the hidden sx-state struct type for an
sx-defined '#objc_class'. Layout:

    __<ClassName>State {
        user_field_0,
        user_field_1,
        ...
    }

This struct is what the runtime's '__sx_state' ivar points at —
separate from the Obj-C object itself, which stays opaque. The
sx method bodies will operate on '*__SxFooState' (after '*Self'
substitution in A.2b) so 'self.field' resolves to a plain struct
field access — A.3's 'free if types align' premise.

M1.2 A.5 will prepend '__sx_allocator: Allocator' so dealloc can
free through the per-instance allocator. Field-by-name access
stays correct across the future repositioning.

Methods / '#extends' / '#implements' members are ignored — only
'.field' contributes. Three unit tests pin: typical-field case,
empty-class case, mixed-member case.

Dead code at this commit — helper isn't called yet. A.2b (body
lowering with '*Self' substitution) wires it in. 170 example
tests + zig build test green.
2026-05-25 21:51:07 +03:00
agra
6cc016cd4f ffi M1.2 A.1: objcTypeEncodingFromSignature helper + encoding table
Derives Apple's runtime type-encoding string from an IR method
signature. Called by class_addMethod(cls, sel, imp, types) when
M1.2 A.4+ synthesise IMPs for sx-defined classes.

Layout: <ret> @ : <param0> <param1> ...   — @ is the receiver,
: is _cmd. Caller passes user-declared params AFTER stripping
'self: *Self'.

Encoding table:
  v=void  B=bool  c=s8/BOOL  s=s16  i=s32  q=s64
  C=u8    S=u16   I=u32      Q=u64  f=f32  d=f64
  @=foreign Obj-C class ptr        #=Class  :=SEL
  *=[*]u8 (C string)               ^v=any other ptr

bool (sx i1) maps to 'B' (C99 _Bool); s8 to 'c' (Apple's BOOL).
Foreign-class pointers detected via foreign_class_map lookup on
the pointee struct name. Other pointers fall to ^v — encoding is
metadata, not ABI, so conservative is safe.

Struct / slice / closure / etc. BAIL via diagnostic
(ObjcEncodingUnsupported) rather than silently mis-encoding, per
CLAUDE.md rejected-patterns rule. Future passes will widen the
table as new shapes show up in real IMPs.

Dead code at this commit — helper isn't called yet. Three unit
tests in src/ir/lower.test.zig pin the primitive / pointer /
Obj-C-class-pointer encodings before A.2 wires the helper in.

170 example tests + zig build test green.
2026-05-25 21:43:53 +03:00
agra
61a2593020 ffi M1.2 A.0: objc_defined_class_cache + scan-pass registration
Adds an insertion-ordered cache on Module for sx-defined Obj-C
classes — every '#objc_class("Cls") { ... }' declaration WITHOUT
'#foreign'. registerForeignClassDecl appends the entry alongside
its existing foreign_class_map insert; lookup helper available
via Module.lookupObjcDefinedClass.

  ObjcDefinedClassEntry { name, *const ast.ForeignClassDecl }

The pointer back into the AST lets later passes (M1.2 A.1+) walk
'members' for fields / methods / '#extends' / '#implements'
without duplicating that data on the entry. Insertion order
matters because class-pair init constructors (A.4) must register
parent classes before children — 'objc_allocateClassPair(super,
...)' resolves super by lookup.

Infrastructure only — no observable behavior change. The cache
is populated but not yet read; A.1+ start pulling from it. 170
example tests + zig build test green.
2026-05-25 21:37:36 +03:00
agra
2b717d9b38 ffi: resolve foreign-class member types through Self substitution (issue-0043)
`inferExprType` for a chained call `Cls.static().instance(...)` never
looked the inner call's foreign-class declaration up, so the outer
dispatch saw a `.s64` receiver, the `foreign_class_map.get(...)` lookup
missed, and lowering emitted `error: unresolved 'method'`. The macOS
target appeared to work because `inline if OS == .ios { ... }` strips
the gated body before lowering — eliding every call that would have
exercised the broken path.

The "lazy-lower" framing in the original issue file was a red herring.

Fix in `src/ir/lower.zig`:

1. `inferExprType` for `.call` with `.field_access` callee now checks
   `foreign_class_map` for both shapes — `Cls.static_method(args)` (object
   identifier matches a foreign-class alias, look up static members) and
   `inst.instance_method(args)` (receiver is a pointer to a foreign-class
   struct, look up non-static members).
2. New helpers `resolveForeignMethodReturnType` and
   `resolveForeignClassMemberType` substitute `*Self` / `Self` to the
   foreign-class struct so a `*Self` return doesn't synthesize a phantom
   `Self`-named struct that future dispatches can't resolve.
3. The Obj-C lowering paths (`lowerObjcMethodCall`, `lowerObjcStaticCall`)
   route through the same helper for `ret_ty` so the IR Ref's type matches
   what `inferExprType` reports.

Regression test at `examples/138-foreign-class-chained-dispatch.sx`
exercises NSObject's `+alloc` / `-init` chain in both shapes —
`*NSObject` return then `*Self` return, and `*Self` then `*Self`. Runs
on the host (macOS) for live exercise; non-macOS hosts fall through to
a stub matching the expected output.

This unblocks Phase 3.2 C4/C5 — the `UIWindow.alloc().initWithWindowScene(scene)`
pattern that surfaced the bug is the cluster's bread-and-butter shape.

167/167 example tests; chess builds clean on macOS, iOS-sim, Android.
2026-05-25 17:52:53 +03:00