Hojun-Cho
d66aef382a
Spine walker now accepts *T root at the last hop (cur->lhs->kind == N_IDENT, pu->kind == TY_PTR), substitutes pointee struct, emits MOVQ off(BP), CX before offset arithmetic. Symmetric in N_DOT and N_ASSIGN. Distinct gate from existing mid-chain *T-field branch (cgen.c:4615) — no shadow. Unblocks task #18 (bufio writer first-field embed). Pre-existing *T-field mid-chain path unchanged.
435 lines
14 KiB
C
435 lines
14 KiB
C
/*
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* 650_dot_chain — chained dotted access through value-struct fields
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* must compile to a single load/store at (base + sum-of-offsets),
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* not silently lower to an undefined global symbol or shuffle stale
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* registers. Drew filed this from worker-bufio when the Hare-shaped
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* `scanner` embed in lib/bufio tripped the cgen.
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*
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* Each fixture exercises a different chain shape. The repro from
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* drew's bug report is row[0]; the rest pin: 3-deep chains, slice
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* pseudo-field tails (`s.buf.len`), global-rooted chains, and
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* mixed leaf widths (u8 / i32 / u32). `&o.i.a` address-of and i8
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* sign-extend leaves are deferred (tasks #9 / #10).
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*
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* Exercises both stages via `ww` (cstage) and `ww_ww` (wwstage)
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* when present, so a regression on either side is caught here.
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*/
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <unistd.h>
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#include <sys/stat.h>
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#include <sys/wait.h>
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static int
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runwait(const char *cmd)
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{
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int rc = system(cmd);
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if (rc == -1) return -1;
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if (WIFEXITED(rc)) return WEXITSTATUS(rc);
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return -1;
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}
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struct row { const char *label; const char *src; int want; };
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static const struct row rows[] = {
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/* Drew's repro: 2-deep value-struct read AND write. Returns
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* o.i.a (=10) + o.x (=5) = 15. */
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{ "drew_2deep_read_write",
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"type inner = struct { a: i32, b: i32, c: i32 };\n"
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"type outer = struct { i: inner, x: i32 };\n"
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"fn main() i32 = {\n"
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" let o: outer; o.i.a = 10; o.x = 5;\n"
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" return o.i.a + o.x;\n"
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"};\n",
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15 },
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/* 3-deep value-struct chain. Proves the spine walker is loop-
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* shaped, not hardcoded to depth 2. */
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{ "value_struct_3deep",
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"type a3 = struct { a: i32 };\n"
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"type a2 = struct { a: a3 };\n"
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"type a1 = struct { a: a2 };\n"
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"fn main() i32 = {\n"
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" let v: a1;\n"
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" v.a.a.a = 7;\n"
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" return v.a.a.a;\n"
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"};\n",
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7 },
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/* Slice pseudo-field tail through a value-struct field: write
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* .ptr/.len/.cap on s.buf where buf: []u8 is a struct field.
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* Read back .len through the same chain. */
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{ "slice_field_pseudo",
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"type bag = struct { buf: []u8, x: i32 };\n"
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"fn main() i32 = {\n"
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" let arr: [8]u8;\n"
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" let i: i32 = 0;\n"
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" for (i < 8) { arr[i] = i: u8; i = i + 1; };\n"
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" let b: bag;\n"
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" b.buf.ptr = &arr[0];\n"
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" b.buf.len = 5;\n"
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" b.buf.cap = 8;\n"
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" b.x = 0;\n"
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" return b.buf.len;\n"
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"};\n",
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5 },
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/* u8 leaf through a chained struct: round-trips a single byte
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* unchanged (no narrow cast in play — direct MOVB write +
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* MOVZBQ read). Pins the leaf-width dispatch in the walker. */
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{ "u8_leaf_through_chain",
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"type holder = struct { val: u8, pad: u8 };\n"
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"type box = struct { h: holder, tag: i32 };\n"
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"fn main() i32 = {\n"
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" let b: box;\n"
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" b.h.val = 99u8;\n"
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" b.h.pad = 0u8;\n"
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" b.tag = 0;\n"
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" return b.h.val: i32;\n"
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"};\n",
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99 },
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/* i32 leaf through a chained struct, value > 255 to confirm the
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* MOVL store width (not silently narrowed to MOVB). Returns 42
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* iff the full 4-byte value round-trips. */
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{ "i32_leaf_through_chain",
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"type holder = struct { val: i32, pad: i32 };\n"
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"type box = struct { h: holder, tag: i32 };\n"
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"fn main() i32 = {\n"
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" let b: box;\n"
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" b.h.val = 0x12345;\n"
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" b.h.pad = 0;\n"
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" b.tag = 0;\n"
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" if (b.h.val == 0x12345) { return 42; };\n"
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" return 0;\n"
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"};\n",
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42 },
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/* u32 leaf through a chained struct. Distinct write + read at
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* the chained leaf, value chosen so the MOVL store + load
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* round-trip preserves all four bytes. */
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{ "u32_leaf_through_chain",
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"type holder = struct { val: u32, pad: u32 };\n"
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"type box = struct { h: holder, tag: i32 };\n"
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"fn main() i32 = {\n"
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" let b: box;\n"
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" b.h.val = 4321u32;\n"
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" b.h.pad = 0u32;\n"
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" b.tag = 0;\n"
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" if (b.h.val == 4321u32) { return 42; };\n"
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" return 0;\n"
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"};\n",
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42 },
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/* Global-rooted chain: write+read through a top-level `let g`.
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* Pins the LEAQ name(SB), CX → MOVQ disp(CX) path on both
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* stages (the local-rooted rows above pin the BP-relative
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* path). 11 + 3 = 14. */
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{ "global_root_chain",
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"type inner = struct { a: i32, b: i32 };\n"
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"type outer = struct { i: inner, x: i32 };\n"
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"let g: outer;\n"
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"fn main() i32 = {\n"
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" g.i.a = 11; g.x = 3;\n"
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" return g.i.a + g.x;\n"
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"};\n",
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14 },
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/* `*T` parameter, single-dot read: `fn f(o: *outer) i32 = o.f`.
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* Already worked via the existing pointer-to-struct-field
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* branch; pinned here so future refactors don't regress it. */
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{ "ptr_root_single_read",
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"type outer = struct { f: i32, g: i32 };\n"
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"fn get(o: *outer) i32 = { return o.f; };\n"
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"fn main() i32 = {\n"
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" let x: outer; x.f = 42; x.g = 0;\n"
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" return get(&x);\n"
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"};\n",
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42 },
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/* `*T` parameter, single-dot write: `fn f(o: *outer) void = …`.
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* Already worked via the via_ptr branch in N_ASSIGN; pinned
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* for the same reason. */
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{ "ptr_root_single_write",
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"type outer = struct { f: i32, g: i32 };\n"
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"fn set(o: *outer) void = { o.f = 42; };\n"
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"fn main() i32 = {\n"
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" let x: outer; x.f = 0; x.g = 0;\n"
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" set(&x);\n"
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" return x.f;\n"
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"};\n",
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42 },
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/* Drew's report shape — `*T` parameter, 2-deep read.
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* Used to lower to `MOVQ a(SB), AX` (link-time undefined ref).
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* Now the spine walker dereferences the root pointer. */
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{ "ptr_root_2deep_read",
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"type inner = struct { a: i32, b: i32 };\n"
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"type outer = struct { i: inner, x: i32 };\n"
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"fn get(o: *outer) i32 = { return o.i.a; };\n"
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"fn main() i32 = {\n"
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" let v: outer; v.i.a = 7; v.i.b = 0; v.x = 0;\n"
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" return get(&v);\n"
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"};\n",
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7 },
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/* `*T` parameter, 2-deep write — bufio.init shape.
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* Previously silently dropped; now MOVQ off(BP), CX +
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* store at total_off(CX). */
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{ "ptr_root_2deep_write",
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"type inner = struct { a: i32, b: i32 };\n"
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"type outer = struct { i: inner, x: i32 };\n"
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"fn set(o: *outer) void = { o.i.a = 5; };\n"
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"fn main() i32 = {\n"
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" let v: outer; v.i.a = 0; v.i.b = 0; v.x = 0;\n"
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" set(&v);\n"
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" return v.i.a;\n"
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"};\n",
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5 },
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/* 3-deep `*T`-rooted: proves the spine walker loops past the
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* pointer-root hop and isn't hardcoded at depth 2. */
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{ "ptr_root_3deep",
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"type a3 = struct { x: i32 };\n"
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"type a2 = struct { a: a3 };\n"
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"type a1 = struct { a: a2 };\n"
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"fn put(p: *a1) void = { p.a.a.x = 9; };\n"
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"fn get(p: *a1) i32 = { return p.a.a.x; };\n"
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"fn main() i32 = {\n"
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" let v: a1; v.a.a.x = 0;\n"
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" put(&v);\n"
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" return get(&v);\n"
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"};\n",
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9 },
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/* `*T` *local* (not just param) — same emit path through
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* localfind, but exercised separately for symmetry. */
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{ "ptr_root_local",
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"type inner = struct { a: i32, b: i32 };\n"
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"type outer = struct { i: inner, x: i32 };\n"
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"fn main() i32 = {\n"
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" let v: outer; v.i.a = 0; v.i.b = 0; v.x = 0;\n"
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" let p: *outer = &v;\n"
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" p.i.a = 13;\n"
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" return p.i.a;\n"
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"};\n",
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13 },
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/* str leaf field through a `*T`-rooted chain — exercises the
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* (AX=ptr, BX=len) convention through the CX-base load. */
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{ "ptr_root_str_leaf",
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"type holder = struct { s: str, pad: i32 };\n"
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"type box = struct { h: holder, tag: i32 };\n"
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"fn put(b: *box) void = { b.h.s = \"abc\"; };\n"
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"fn main() i32 = {\n"
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" let b: box;\n"
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" let empty: str; b.h.s = empty; b.h.pad = 0; b.tag = 0;\n"
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" put(&b);\n"
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" if (b.h.s.len == 3) { return 42; };\n"
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" return 0;\n"
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"};\n",
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42 },
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/* slice pseudo-field on a `*T`-rooted chain. .len of an empty
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* slice round-trips through the CX-base load. */
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{ "ptr_root_slice_pseudo",
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"type bag = struct { buf: []u8, x: i32 };\n"
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"fn setlen(b: *bag, n: i32) void = { b.buf.len = n; };\n"
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"fn main() i32 = {\n"
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" let b: bag;\n"
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" let nope: []u8; b.buf = nope; b.x = 0;\n"
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" setlen(&b, 5);\n"
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" return b.buf.len: i32;\n"
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"};\n",
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5 },
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/* f64 leaf field through a `*T`-rooted chain — exercises the
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* X0 spill / MOVSD store path off the CX base. */
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{ "ptr_root_f64_leaf",
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"type holder = struct { v: f64, pad: i32 };\n"
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"type box = struct { h: holder, tag: i32 };\n"
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"fn put(b: *box) void = { b.h.v = 0.5f64; };\n"
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"fn main() i32 = {\n"
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" let b: box; b.h.v = 0.0f64; b.h.pad = 0; b.tag = 0;\n"
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" put(&b);\n"
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" if (b.h.v == 0.5f64) { return 42; };\n"
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" return 0;\n"
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"};\n",
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42 },
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/* Sub-word leaf widths through a `*T`-rooted chain — pins
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* fldloadop / fldstoreop on the CX-base path. u8/i8/u16/i16/i32
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* all stored then read back through the inner pointer. */
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{ "ptr_root_subword_u8",
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"type holder = struct { v: u8, pad: u8 };\n"
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"type box = struct { h: holder, tag: i32 };\n"
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"fn put(b: *box) void = { b.h.v = 99u8; };\n"
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"fn main() i32 = {\n"
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" let b: box; b.h.v = 0u8; b.h.pad = 0u8; b.tag = 0;\n"
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" put(&b);\n"
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" return b.h.v: i32;\n"
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"};\n",
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99 },
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{ "ptr_root_subword_i32",
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"type holder = struct { v: i32, pad: i32 };\n"
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"type box = struct { h: holder, tag: i32 };\n"
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"fn put(b: *box) void = { b.h.v = 0x12345; };\n"
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"fn main() i32 = {\n"
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" let b: box; b.h.v = 0; b.h.pad = 0; b.tag = 0;\n"
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" put(&b);\n"
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" if (b.h.v == 0x12345) { return 42; };\n"
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" return 0;\n"
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"};\n",
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42 },
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{ "ptr_root_subword_i16",
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"type holder = struct { v: i16, pad: i16 };\n"
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"type box = struct { h: holder, tag: i32 };\n"
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"fn put(b: *box) void = { b.h.v = 4321i16; };\n"
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"fn main() i32 = {\n"
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" let b: box; b.h.v = 0i16; b.h.pad = 0i16; b.tag = 0;\n"
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" put(&b);\n"
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" if (b.h.v == 4321i16) { return 42; };\n"
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" return 0;\n"
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"};\n",
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42 },
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/* Negative signed leaf widths through a `*T`-rooted chain.
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* Stored value's sign bit must round-trip — pins localloadop /
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* fldloadop sign-extension on the CX-base path so `*T`-rooted
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* chains don't silently widen to a positive bit pattern. i8, i16
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* and i32 each store −7 and check `< 0` after the chained read. */
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{ "ptr_root_subword_i8_neg",
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"type holder = struct { v: i8, pad: i8 };\n"
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"type box = struct { h: holder, tag: i32 };\n"
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"fn put(b: *box) void = { b.h.v = -7i8; };\n"
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"fn main() i32 = {\n"
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" let b: box; b.h.v = 0i8; b.h.pad = 0i8; b.tag = 0;\n"
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" put(&b);\n"
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" let r: i32 = b.h.v: i32;\n"
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" if (r == -7) { return 42; };\n"
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" return 0;\n"
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"};\n",
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42 },
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{ "ptr_root_subword_i16_neg",
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"type holder = struct { v: i16, pad: i16 };\n"
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"type box = struct { h: holder, tag: i32 };\n"
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"fn put(b: *box) void = { b.h.v = -7i16; };\n"
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"fn main() i32 = {\n"
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" let b: box; b.h.v = 0i16; b.h.pad = 0i16; b.tag = 0;\n"
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" put(&b);\n"
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" let r: i32 = b.h.v: i32;\n"
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" if (r == -7) { return 42; };\n"
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" return 0;\n"
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"};\n",
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42 },
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{ "ptr_root_subword_i32_neg",
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"type holder = struct { v: i32, pad: i32 };\n"
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"type box = struct { h: holder, tag: i32 };\n"
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"fn put(b: *box) void = { b.h.v = -7; };\n"
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"fn main() i32 = {\n"
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" let b: box; b.h.v = 0; b.h.pad = 0; b.tag = 0;\n"
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" put(&b);\n"
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" if (b.h.v < 0) { return 42; };\n"
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" return 0;\n"
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"};\n",
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42 },
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/* Round-trip across the aliasing seam: caller writes via the
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* local value, callee reads via the `*T`-rooted chain — and
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* vice versa. Pins that both branches index the SAME slot
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* (same field offsets resolved off the right base). */
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{ "ptr_root_roundtrip_local_write_ptr_read",
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"type inner = struct { a: i32, b: i32 };\n"
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"type outer = struct { i: inner, x: i32 };\n"
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"fn get(o: *outer) i32 = { return o.i.a; };\n"
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"fn main() i32 = {\n"
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" let o: outer; o.i.a = 0; o.i.b = 0; o.x = 0;\n"
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" let p: *outer = &o;\n"
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" o.i.a = 42;\n"
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" return get(p);\n"
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"};\n",
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42 },
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{ "ptr_root_roundtrip_ptr_write_local_read",
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"type inner = struct { a: i32, b: i32 };\n"
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"type outer = struct { i: inner, x: i32 };\n"
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"fn main() i32 = {\n"
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" let o: outer; o.i.a = 0; o.i.b = 0; o.x = 0;\n"
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" let p: *outer = &o;\n"
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" p.i.a = 42;\n"
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" return o.i.a;\n"
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"};\n",
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42 },
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};
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static int
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run_driver(const char *driver, const struct row *r, int i)
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{
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char src[64], tmpdir[64], cmd[1024];
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snprintf(src, sizeof src, "/tmp/wdc_%d_%d.ww", getpid(), i);
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snprintf(tmpdir, sizeof tmpdir, "/tmp/wdc_%d_d_%d", getpid(), i);
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FILE *f = fopen(src, "wb");
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if (!f) return -1;
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fputs(r->src, f);
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fclose(f);
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mkdir(tmpdir, 0755);
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snprintf(cmd, sizeof cmd, "cd %s && %s build %s",
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tmpdir, driver, src);
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if (runwait(cmd) != 0) {
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fprintf(stderr, "row[%s]: build via %s failed\n",
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r->label, driver);
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unlink(src); rmdir(tmpdir);
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return -1;
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}
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const char *base = strrchr(src, '/');
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base = base ? base + 1 : src;
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char outbin[128];
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snprintf(outbin, sizeof outbin, "%s/%s", tmpdir, base);
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char *dot = strrchr(outbin, '.');
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if (dot && strcmp(dot, ".ww") == 0) *dot = '\0';
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int got = runwait(outbin);
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unlink(src); unlink(outbin); rmdir(tmpdir);
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return got;
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}
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int
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main(void)
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{
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const char *bin = getenv("BIN");
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if (!bin) bin = "out/bin";
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char absbin[1024];
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if (bin[0] != '/') {
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char cwd[1024];
|
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if (getcwd(cwd, sizeof cwd) == NULL) return 1;
|
||
snprintf(absbin, sizeof absbin, "%s/%s", cwd, bin);
|
||
bin = absbin;
|
||
}
|
||
|
||
char cdrv[1024];
|
||
snprintf(cdrv, sizeof cdrv, "%s/ww", bin);
|
||
char wdrv[1024];
|
||
snprintf(wdrv, sizeof wdrv, "%s/ww_ww", bin);
|
||
|
||
struct { const char *name; const char *path; int gated_on_existence; }
|
||
drivers[] = {
|
||
{ "cstage", cdrv, 0 },
|
||
{ "wwstage", wdrv, 1 },
|
||
{ NULL, NULL, 0 },
|
||
};
|
||
|
||
int n = (int)(sizeof rows / sizeof rows[0]);
|
||
int total = 0, fail = 0;
|
||
for (int d = 0; drivers[d].name; d++) {
|
||
if (drivers[d].gated_on_existence
|
||
&& access(drivers[d].path, X_OK) != 0) {
|
||
fprintf(stderr, "dot_chain: skip %s (no %s)\n",
|
||
drivers[d].name, drivers[d].path);
|
||
continue;
|
||
}
|
||
for (int i = 0; i < n; i++) {
|
||
int got = run_driver(drivers[d].path, &rows[i], i);
|
||
total++;
|
||
if (got != rows[i].want) {
|
||
fprintf(stderr,
|
||
"dot_chain[%s][%s]: exit=%d want=%d\n",
|
||
drivers[d].name, rows[i].label,
|
||
got, rows[i].want);
|
||
fail++;
|
||
}
|
||
}
|
||
}
|
||
if (fail) {
|
||
fprintf(stderr,
|
||
"dot_chain: %d/%d fixtures failed\n", fail, total);
|
||
return 1;
|
||
}
|
||
printf("dot_chain: %d/%d ok\n", total, total);
|
||
return 0;
|
||
}
|