91/91 regression tests pass (+ffi-04-fp-struct).
Single-file regression net for the all-float / all-double aggregate
ABI path:
FQuad — 16 B, 4×f32 (same slot as ffi-02's Vec4f)
DQuad — 32 B, 4×f64 (UIEdgeInsets-shape — the f32-vs-f64 landmine)
Already nominally covered by ffi-02's Vec4f, but pinning it as a
focused single-file test means a future ABI rule change that breaks
the HFA path fails *this* test directly without a noisy drag-in from
the multi-shape baseline.
DQuad at 32 B straddles the AAPCS64 HFA limit (≤4 floats of same
type, total ≤64 B); it stays as a struct value passed through
v0..v3 rather than going indirect. The snapshot confirms the values
arrive intact.
90/90 regression tests pass (+ffi-03-large-struct).
vendors/ffi_large_struct/{.h,.c} defines:
Big24 — 24 B, three s64 (byval params + sret return)
Big48 — 48 B, six s64 (same path, larger)
`make / rotate-or-reverse / sum` helpers per shape. The sx-side
example imports via `#source` only and declares matching structs +
hand-written #foreign decls.
Snapshot pins today's >16-byte aggregate ABI now that the
emit_llvm.zig sret-return transform is in place (previous commit).
That gives us a regression net for all four C-ABI aggregate slots
in one place:
≤8 B int — i64 coercion (ffi-01 vec-likes)
9..16 B int — [2 x i64] coercion (ffi-02 Pair64/Quad32, 101)
16 B HFA — struct, no coercion (ffi-02 Vec2/Vec4f)
>16 B — byval params + sret (this commit)
Now that emit_llvm.zig bridges the struct<->[2 x i64] ABI mismatch
(previous commit), the 9..16-byte integer-only shapes round-trip
cleanly. Extended `examples/ffi-02-small-struct.sx` to cover all
four aggregate ABI slots in one place:
Vec2 — 8 B, two f32 (register pair, float)
Vec4f — 16 B, four f32 (HFA — homogeneous float aggregate)
Pair64 — 16 B, two s64 (9..16 B int — [2 x i64] coercion slot)
Quad32 — 16 B, four s32 (same slot as Pair64)
Vendor helpers (`vendors/ffi_structs/{ffi_structs.h,ffi_structs.c}`)
grow `ffi_pair64_*` + `ffi_quad32_*` companions. Snapshot updated
to capture the full output. 89/89 regression tests pass.
`examples/101-ffi-medium-struct.sx` keeps a minimal focused repro
of the Pair64 case so the issue's emergence-and-fix history stays
greppable.
Resolves issue-0036 (LLVM verifier failure on 16-byte integer-only
struct by value through #foreign). The mismatch:
Call parameter type does not match function signature!
%load = load { i64, i64 }, ptr %alloca, align 8
[2 x i64] %call = call [2 x i64] @fn({ i64, i64 } %load)
`abiCoerceParamType` had already chosen `[2 x i64]` for 9..16-byte
non-HFA structs (the AAPCS64 / SysV AMD64 register-pair ABI slot for
that size class) on the foreign-decl side, but `coerceArg` only knew
how to bridge struct<->integer (the ≤8 B case) — not struct<->array.
LLVM's verifier rejects type-mismatched call args, so the call site
never landed.
Added the symmetric branches in coerceArg:
- Struct -> Array : alloca <array>; store <struct>; load <array>
- Array -> Struct : alloca <array>; store <array>; load <struct>
Both use the LLVM opaque-pointer memory-bitcast pattern already in
place for the integer case. They're paired with the existing
i64 <-> small-struct bridge so all four (≤8 B int, 9..16 B int,
16 B HFA, >16 B byval) ABI slots round-trip cleanly through
emit_llvm now.
File mechanics: promotes the issue-0036 repro to a focused feature
example per CLAUDE.md's issue-resolution workflow:
examples/issue-0036.sx -> examples/101-ffi-medium-struct.sx
tests/expected/issue-0036.{txt,exit} -> tests/expected/101-ffi-medium-struct.{txt,exit}
vendors/issue_0036/issue_0036.c -> vendors/ffi_medium_struct/ffi_medium_struct.c
Snapshot updated to the passing output. 89/89 regression tests pass;
chess Android build still clean.
Surfaced while writing the ffi-02-small-struct.sx baseline. The sx
#foreign decl lowers `{ s64, s64 }` (and other 16-byte integer-only
shapes like `{ s32, s32, s32, s32 }`) to `[2 x i64]` for the small-
struct register-pair ABI on AAPCS64 / SysV AMD64, but the call site
loads the struct as `{ i64, i64 }`. The two types must agree for the
LLVM verifier to accept the call:
Call parameter type does not match function signature!
%load = load { i64, i64 }, ptr %alloca, align 8
[2 x i64] %call = call [2 x i64] @issue0036_swap({ i64, i64 } %load)
Float-only 16-byte aggregates (e.g. Vec4f) work because they route
through the HFA path which keeps the struct representation. See
examples/ffi-02-small-struct.sx for the working cases.
Phase 1's #foreign lowering rework is the natural place to unify
these representations; check there before fixing inline.
88/88 regression tests pass (+ffi-02-small-struct).
vendors/ffi_structs/ defines:
Vec2 — 8 B, two f32 — register-pair (float) ABI
Vec4f — 16 B, four f32 — homogeneous float aggregate (HFA) on AAPCS64
Both pass cleanly today: the sx-side struct declarations match the C
ABI for these float-only shapes, and the call-site / foreign-decl
type representations agree.
`#source` only (no `#include`) — c_import's type mapping rewrites
struct-typed params/returns to *void, which would link but pass
through the wrong ABI silently. The hand-written #foreign decls keep
sx's struct types end to end.
16-byte integer-only shapes (`{s64, s64}`, `{s32, s32, s32, s32}`)
discovered to trip the LLVM verifier (`[2 x i64]` vs `{ i64, i64 }`
mismatch between foreign decl and call site). Excluded from this
baseline; filed separately in the next commit as issue-0036.
87/87 regression tests pass (was 86; +ffi-01-primitives).
vendors/ffi_primitives/{.h,.c} exposes a trivial identity roundtrip
per primitive C type — int/uint/short/ushort/long long/unsigned long
long/signed char/unsigned char/float/double/void* — plus two-arg
add helpers (int + double) for multi-arg ABI exercise. The sx-side
example imports the .h via `#import c { #include / #source }` and
prints each result; the snapshot in tests/expected pins today's
parameter + return ABI so Phase 1's #objc_call / #jni_call lowering
work can't silently regress primitive marshalling.
Two findings logged in current/CHECKPOINT-FFI.md's Known issues
section (current behavior, not new bugs): (1) c_import.zig maps
`signed char` -> `u8` not `s8`, and (2) sx integer-literal parser
rejects values >= 2^63 as overflow even when the receiver is u64.
Both worked around in this test without blocking the baseline.
When lowering `self.cb()` from inside a method whose receiver is *Self,
the field-access path passed the receiver pointer (not the aggregate)
to `structGet`, which then produced `call void undef(ptr undef)` at
the LLVM level — undefined at runtime, corrupted adjacent globals when
it transferred control to a garbage pointer. Auto-load through the
pointer first so structGet receives a real aggregate.
Discovered while building the new AndroidPlatform's `run_frame_loop` —
calling the stored frame closure as `self.frame_closure()` zeroed
out adjacent globals because the undef call jumped into random memory.
Added examples/100-closure-field-call-via-self-ptr.sx as the locked-in
regression: both direct (`self.cb()`) and hoisted (`fn := self.cb; fn();`)
forms must yield identical IR + behavior. 86/86 regression tests pass.
Protocol structs registered via registerProtocolDecl carry a new
is_protocol flag; the ?T paths in sizeOf/typeSizeBytes/toLLVMType
recognise it and lay out ?Protocol as the protocol struct itself
(ctx == null IS the "none" state), matching how ?Closure / ?*T are
sentinel-shaped — no extra storage.
Method dispatch on ?Protocol auto-unwraps in lowerCall's field-access
path; the unwrap is structurally a no-op so we just rebind obj_ty to
the payload type. resolveCallParamTypes extended for optional-protocol
receivers so enum-literal args (gpu.create_texture(.r8, ...)) get the
right target_type and don't silently collapse to tag=0 : s32 — same
issue-0031-class bug closed in Session 66, one type-system layer
deeper.
Library: UIRenderer / UIPipeline / GlyphCache migrated from the verbose
gpu: GPU = ---; has_gpu: bool pattern to gpu: ?GPU = null. set_gpu no
longer maintains a parallel bool flag.
Bundled: dock.sx threads delta_time as a struct field rather than via
a global pointer (cleanup unrelated to issue-0028, committed alongside).
Verified: 85/85 regression tests pass; iOS-sim chess + macOS chess
both render correctly post-migration.
Three stacked compiler bugs were causing iOS-sim chess to crash inside
[MTLTexture replaceRegion:...]. Fixing them lets every replaceRegion call
site succeed (1×1 RGBA8, 1MB R8 atlas, 440×440 chess pieces).
Path B for callconv(.c) fn-pointer casts:
- FunctionInfo now carries call_conv: CallConv (TypeInfo.CallConv) so
function-type interning distinguishes sx-CC from C-CC. Inst.zig's
Function.CallingConvention aliases the same enum.
- Parser accepts an optional `callconv(.c)` suffix on fn-pointer type
spellings (factored into parseOptionalCallConv() shared with parseFnDecl
and parseLambda).
- resolveFunctionType passes the parsed CC through functionTypeCC().
- .call_indirect reads fp.call_conv == .c and applies the C-ABI
alloca+materialize for >16B aggregate args (Path A's behaviour at .call).
Apple ARM64 ABI (drop LLVM byval):
- Side-by-side asm diff vs clang's emission for the equivalent C call site
showed LLVM's `byval` attribute lowers Apple-arm64 byval on the stack,
while clang passes the struct via a pointer in the next int register
(x2 for replaceRegion:). The runtime objc_msgSend dispatch path expects
clang's convention.
- Dropped the byval attribute from the function-signature emission and
from both call sites (.call and .call_indirect). The materialize-into-
alloca + pass-plain-ptr pattern stays — the call site now matches
clang's `mov x2, sp` exactly.
- Path A's sx-to-sx case continues to work since both ends use plain ptr
(caller does alloca+store+pass, callee loads from the ptr in prologue).
Protocol dispatch (emitProtocolDispatch):
- Untargeted `null` lowers as const_null with type .void (per
target_type orelse .void). The "wrap-value-in-alloca-pass-pointer"
branch alloca'd a void slot, which LLVM's IRBuilder asserts on —
EXC_BREAKPOINT in getTypeSizeInBits, manifesting as exit 133 / SIGTRAP
when building the chess game. Fixed by re-emitting as
constNull(void_ptr) when arg_ty == .void && expected_ty == void_ptr.
- is_pointer_ty only recognized .pointer, so [*]T (many_pointer) was
alloca-wrapped — the heap pixels pointer from stbi_load was stored
into a stack slot and the slot's address was passed as the *void arg.
Fixed by extending the check to `.pointer or .many_pointer`.
metal.sx call sites + lifecycle guards:
- msg_replace (replaceRegion:, MTLRegion = 48B) and the two setScissorRect:
sites (MTLScissorRect = 32B) now spell their fn-pointer types with
by-value params + callconv(.c) — the *MTLRegion/@local workaround is
gone.
- metal_begin_frame_ios bails before nextDrawable when pixel_w/h are 0
(drawableSize 0×0 makes nextDrawable abort via XPC).
- metal_init_ios only sets drawableSize when dims are positive.
- begin_frame's encoder/cmd_buffer failure paths now clear self.drawable
so a partial failure doesn't leak a drawable back into the pool.
Examples + tests:
- examples/86-callconv-c-fnptr-large-aggregate.sx — new, covers Path B
with C-CC fn-ptr cast.
- examples/87-fnptr-cast-large-aggregate.sx — renamed from issue-0025.sx,
covers Path B with default sx-CC (the negative case).
- examples/85-cc-c-large-aggregate.sx — from Session 60, covers Path A.
- examples/issue-0014.sx, issue-0024.sx, issue-0025.sx — removed
(resolved earlier this work).
71 regression tests pass, 0 failed. Chess game builds clean for iOS sim
and reaches its frame loop without aborting. Runtime: chess UI still
doesn't render — remaining issue is in the UIKit lifecycle / CAMetalLayer
setup (legacy-app vs scene-API hybrid), not a compiler bug. See
current/CHECKPOINT.md "Next step" for the diagnosis + options.
Phase 8 step 3a of the Metal renderer port:
- New library/modules/gpu/ with types.sx (handles + ClearColor +
TextureFormat enum), api.sx (GPU :: protocol { ... } covering the
lifecycle / per-frame / resource / per-draw surface), and metal.sx
(MetalGPU backend implementing the protocol against CAMetalLayer).
Resource handles are 1-based indices into backend List(*void) tables.
MTL aggregates >16 bytes (MTLRegion, MTLScissorRect) pass via *T to
match arm64 Apple's indirect-by-reference ABI; MTLClearColor + CGSize
go through the HFA path as direct fn-pointer casts on objc_msgSend.
- UIKitPlatform got a gpu_mode: GpuMode toggle + sibling SxMetalView
class registration. In metal mode init skips EAGL context, the
did_finish_launching IMP skips the EAGL drawable-properties dict,
layoutSubviews reads the layer's bounds * dpi_scale into pixel_w/h
instead of allocating a GL renderbuffer, and end_frame is a no-op
(the MetalGPU owns its own present).
- examples/63-metal-clear.sx verifies the pipeline end-to-end on iOS
sim — compiles a pass-through MSL shader (packed_float2/packed_float4
to avoid alignment padding), uploads 3 vertices, draws a colored
triangle on a dark-blue clear.
Compiler fixes (filed-and-fixed in this branch):
- inline if X { return E; } followed by a fall-through final expression
no longer emits two terminators into the same basic block. Verified
by examples/83-inline-if-return-fallthrough.sx.
- Top-level type alias Name :: u32; now resolves correctly as the type
annotation on a global variable (was treated as ptr {}, breaking
comparisons + initializers). Verified by examples/84-global-type-alias.sx.
Issue->feature promotion:
- 16 historical examples/issue-NNNN.sx repros now confirmed-fixed and
renamed to focused feature names (67-82). Each gains a
tests/expected/*.txt + .exit pair so the regression suite covers them.
- 5 stale issue repros deleted (subsumed by broader tests).
Regression suite: 68 passing, 0 failed. macOS chess builds + runs; wasm
chess builds; iOS sim GLES chess still renders the full board; iOS sim
Metal demo renders the triangle.
