0bb7b8cc27
109/109 regression tests pass; chess Android + iOS-sim still
build clean.
Root cause: sx's `xx <ptr>` cast targeting an integer type
(common pattern: `xx u64 = xx @some_global`) lowered to a no-op
because `coerceToType` had branches for int↔float and same-kind
widen/narrow, but nothing for pointer↔integer. The cast left the
value as a pointer Ref, and `emitInst`'s `.ret` arm tried to
coerce a `ptr` value to an `i64` slot — coerceArg had no
ptr↔int branch either, fell through to undef.
Why it worked in main but failed in helpers: an
`alloca u64`+`store ptr @g, alloca`+`load i64, alloca` sequence
preserves the address bits as raw memory, so the
"store-then-load through an alloca" workaround happened to do
the right thing without a real cast. A `ret i64 <ptr>` has no
such intermediate slot and triggers an LLVM type mismatch.
Fix layered into two existing IR opcodes:
lower.zig (coerceToType):
new branch — when src and dst types are ptr↔int, emit a
`bitcast` IR opcode with the right from/to. Mirrors how
int↔float emits `.int_to_float` / `.float_to_int`.
emit_llvm.zig (.bitcast arm):
dispatch ptr→int to `LLVMBuildPtrToInt` (+ trunc/zext if the
target int width != 64), int→ptr to `LLVMBuildIntToPtr`. The
"real bitcast" path stays for same-kind type punning.
Modern LLVM's BuildBitCast rejects ptr↔int directly, hence
the dispatch.
The fix also closes a quiet behavior gap that affected non-`#foreign`
globals (any `xx @<global>` from a helper fn). Surfaced while
investigating issue-0037; verified independently with a
non-`#foreign` sx-side global of type `s64`.
File mechanics: issue-0037 promoted to a focused feature example
per CLAUDE.md's resolution flow:
examples/issue-0037.sx -> examples/102-foreign-global-from-helper.sx
tests/expected/issue-0037.{txt,exit} -> tests/expected/102-foreign-global-from-helper.{txt,exit}
ffi-objc-call-03 + ffi-objc-call-06 IR snapshots updated to
reflect the ptr→int store-via-ptrtoint shape that's now correct
at the LLVM-IR level (same bits in memory, but properly typed).
29 lines
948 B
Plaintext
29 lines
948 B
Plaintext
// `xx @<foreign_global>` round-trips through a non-main helper
|
|
// function: the helper's `xx @__stdinp` cast lowers to a `bitcast`
|
|
// IR opcode that emit_llvm.zig dispatches to `LLVMBuildPtrToInt`
|
|
// (BitCast doesn't accept ptr↔int on modern LLVM with opaque
|
|
// pointers), and a `u64`-returning function correctly returns
|
|
// the address.
|
|
//
|
|
// Was issue-0037 — the helper used to emit `ret i64 undef` because
|
|
// `coerceToType` had no pointer↔integer case, so the explicit
|
|
// `xx ptr` cast produced an unchanged pointer value handed to a
|
|
// `ret i64` slot.
|
|
|
|
#import "modules/std.sx";
|
|
|
|
__stdinp : *void #foreign;
|
|
|
|
stdinp_addr_via_helper :: () -> u64 {
|
|
xx @__stdinp;
|
|
}
|
|
|
|
main :: () -> s32 {
|
|
direct : u64 = xx @__stdinp;
|
|
via_helper := stdinp_addr_via_helper();
|
|
print("direct non-null = {}\n", direct != 0);
|
|
print("helper non-null = {}\n", via_helper != 0);
|
|
print("eq = {}\n", direct == via_helper);
|
|
0;
|
|
}
|