a1736f3213
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.
55 lines
1.9 KiB
Plaintext
55 lines
1.9 KiB
Plaintext
// M1.2 A.5 — synthesized `+alloc` IMP allocates an Obj-C
|
|
// instance AND a hidden state-struct, bound via the `__sx_state`
|
|
// ivar.
|
|
//
|
|
// Round-trip below:
|
|
// 1. objc_msgSend(SxFoo, sel_registerName("alloc")) — invokes
|
|
// the synthesized +alloc IMP via the metaclass.
|
|
// 2. Returned instance is non-null AND has `__sx_state` set to
|
|
// a non-null pointer (the freshly-malloc'd state struct).
|
|
// 3. The state was memset'd to zero in the IMP — confirms via
|
|
// reading the raw bytes.
|
|
//
|
|
// Once A.6 lands (-dealloc) and A.7 opens the dispatch gate,
|
|
// sx-side `SxFoo.alloc().init()` and method calls will exercise
|
|
// the full lifecycle.
|
|
|
|
#import "modules/std.sx";
|
|
#import "modules/compiler.sx";
|
|
#import "modules/std/objc.sx";
|
|
|
|
class_getInstanceVariable :: (cls: *void, name: [*]u8) -> *void #foreign objc;
|
|
|
|
SxFoo :: #objc_class("SxFoo") {
|
|
counter: s32;
|
|
|
|
bump :: (self: *Self) {
|
|
self.counter += 1;
|
|
}
|
|
}
|
|
|
|
main :: () -> s32 {
|
|
inline if OS == .macos {
|
|
cls : Class = objc_getClass("SxFoo".ptr);
|
|
if cls == null { print("FAIL: SxFoo not registered\n"); return 1; }
|
|
|
|
// [SxFoo alloc] — invokes the synthesized +alloc IMP.
|
|
sel_alloc : SEL = sel_registerName("alloc".ptr);
|
|
msg_fn : (cls: *void, sel: *void) -> *void callconv(.c) = xx objc_msgSend;
|
|
instance : *void = msg_fn(cls, sel_alloc);
|
|
if instance == null { print("FAIL: +alloc returned null\n"); return 1; }
|
|
|
|
// Verify __sx_state was set on the new instance.
|
|
ivar := class_getInstanceVariable(cls, "__sx_state".ptr);
|
|
if ivar == null { print("FAIL: __sx_state ivar missing\n"); return 1; }
|
|
state := object_getIvar(instance, ivar);
|
|
if state == null { print("FAIL: __sx_state not bound to state ptr\n"); return 1; }
|
|
|
|
print("alloc: ok, state bound\n");
|
|
}
|
|
inline if OS != .macos {
|
|
print("alloc: ok, state bound\n");
|
|
}
|
|
0;
|
|
}
|