test: port the w6a ELF-object observers to ww

elfobj_test.ww (test/object, on testenv) absorbs 500_w6a, 510_dataw,
and 520_datar: ELF64 header magic/class over the 4 inline programs,
DATAW section/symbol layout plus the 6-section no-DATAW legacy
invariant 991 depends on, and the DATAR .rela.data reloc through
link and run. Strengthened: the reloc symbol is resolved to
'greeting' (declared but never implemented in the C carrier).
This commit is contained in:
2026-08-08 14:46:05 +09:00
parent 6657d68349
commit 42d8fbe950
5 changed files with 364 additions and 542 deletions

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@@ -388,6 +388,15 @@ ASM_WW_TESTS = test/asm/modshadow_test.ww test/asm/sret_test.ww \
test/asm/callarg_test.ww test/asm/chain_test.ww \
test/asm/dataemit_test.ww test/asm/matchdispatch_test.ww
ASM_WW_TARGETS = $(ASM_WW_TESTS:%=wwtest/%)
# Ww-native assembler/linker OBJECT-level observers: single-file ww
# tests under test/object/ on the test/testenv helper package, porting
# the residual w6a/w6l artifact C carriers (ELF section/symbol/reloc
# layout, program-header split and BSS trim, archive selectivity,
# linker flag capacity, assembler input gates). Compiler/driver gates
# like test/sep: they run under test-compiler.
OBJECT_WW_TESTS = test/object/elfobj_test.ww
OBJECT_WW_TARGETS = $(OBJECT_WW_TESTS:%=wwtest/%)
BOOTSTRAP_WRAPPER_SOURCES = test/wcc/950_selfcheck.c \
test/wcc/991_w6a_ww.c \
test/wcc/992_w6l_ww.c test/wcc/993_ww_ww.c \
@@ -473,7 +482,8 @@ test-compiler-smoke: $(WWFIXTURE_BIN) $(BIN)/w6c_ww $(BIN)/w6a_ww \
# gates that cannot be represented by a single compiler fixture, plus the
# ww-native sep observers that replaced the 989_sep* carriers.
test-compiler: $(WWFIXTURE_BIN) $(WRAPPER_TOOLS) $(COMPILER_WRAPPER_BINS) \
$(SEP_WW_TARGETS) $(XMOD_WW_TARGETS) $(ASM_WW_TARGETS)
$(SEP_WW_TARGETS) $(XMOD_WW_TARGETS) $(ASM_WW_TARGETS) \
$(OBJECT_WW_TARGETS)
@$(CURDIR)/$(WWFIXTURE_BIN) -j $(JOBS)
@set -e; for t in $(COMPILER_WRAPPER_BINS); do \
echo "compiler artifact $$t"; BIN=$(CURDIR)/$(BIN) $(CURDIR)/$$t; \
@@ -543,6 +553,18 @@ $(ASM_WW_TARGETS): wwtest/%: $(BIN)/ww $(BIN)/w6c $(BIN)/w6a $(BIN)/w6l \
-w $(WWBUILD)/wwtest/$(subst /,_,$*) \
-I $(CURDIR)/test $*
# The object observers feed hand-written .s (and w6c output) to the
# assemblers and linkers of both stages and parse the resulting ELF
# artifacts, so w6c plus both stages' w6a/w6l are prerequisites;
# libwwrt.a carries the $(OBJ)/rt/start.o the archive rows link.
$(OBJECT_WW_TARGETS): wwtest/%: $(BIN)/ww $(BIN)/w6c $(BIN)/w6a \
$(BIN)/w6l $(LIB)/libwwrt.a $(BIN)/w6a_ww $(BIN)/w6l_ww
@echo "ww test $*"
@mkdir -p $(WWBUILD)/wwtest/$(subst /,_,$*)
@WW_TEST_REPO=$(CURDIR) $(BIN)/ww test \
-w $(WWBUILD)/wwtest/$(subst /,_,$*) \
-I $(CURDIR)/test $*
test-lang: $(LANG_TEST_TARGETS)
test-library: $(LIBRARY_TEST_TARGETS) $(BIN)/w6c $(BIN)/w6c_ww \

341
test/object/elfobj_test.ww Normal file
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@@ -0,0 +1,341 @@
package elfobj_test;
// w6a OBJECT-level observers. Ports of the retired native carriers
// test/wcc/500_w6a.c, 510_dataw.c, and 520_datar.c; every assertion
// preserved.
//
// elf64header (500) — all 4 inline programs: w6c exit 0, w6a exit 0,
// and the .o opens with the ELF magic + ELFCLASS64 ident byte.
//
// dataw (510) — hand-written DATAW .s: e_shnum == 7 (NULL, .text,
// .rela.text, .data, .symtab, .strtab, .shstrtab); .data is
// SHT_PROGBITS, ALLOC|WRITE, non-EXECINSTR, 8 bytes equal to the LE
// i64 42; symbol `counter` sits in .data at st_value 0.
//
// nodataw (510) — a .s without DATAW keeps the legacy 6-section
// layout with no .data; test 991 (selfhost w6a .o byte-diff, the
// terminal bootstrap gate) depends on that invariant.
//
// datar (520) — DATAR emits exactly one R_X86_64_64 entry at offset 0
// in .rela.data; w6l links the .o and the binary prints the 5 bytes
// `hello` through the relocated pointer and exits 0. Strengthened
// over the carrier: the reloc's symbol index is resolved through
// .symtab and must name `greeting` (the C code declared but never
// implemented that check).
//
// Dropped C machinery, not assertions: wwtestpkg.h package-clause
// injection (the sources here spell `package main;` out) and per-file
// unlink accounting (testenv.clean asserts the removal).
import os;
import os.exec;
import strconv;
import strings;
import testenv;
import time;
fn fail(label: str, why: str) void = {
let m: str = strings.concat("elfobj FAIL: ", label, " -- ", why,
"\n");
os.write(2, m.ptr, m.len: u64);
assert(false);
};
fn tmo() time.duration = {
return (240i64 * (time.second: i64)): time.duration;
};
// -1 encodes an abnormal (non-EXIT) termination, never a valid code.
fn runcode(dir: str, name: str, argv: []str) i32 = {
let co: testenv.commandout;
testenv.runcommand(dir, dir, name, argv, tmo(), &co);
if (co.termination != exec.termination.EXIT) { return -1; };
return co.code;
};
// itos returns a view into a static buffer; dup materializes it.
fn dec(n: i32) str = {
return strings.dup(strconv.itos(n: int, strconv.base.DEC));
};
// External-ABI constants (System V gABI, ELF64 relocatable objects) —
// the layout contract w6a's obj writer encodes: Ehdr e_shoff at 40
// (u64), e_shnum at 60 (u16), e_shstrndx at 62 (u16); Shdr entries of
// 64 bytes with sh_name +0 (u32), sh_type +4 (u32), sh_flags +8
// (u64), sh_offset +24 (u64), sh_size +32 (u64), sh_link +40 (u32);
// Sym64 entries of 24 bytes with st_name +0 (u32), st_shndx +6 (u16),
// st_value +8 (u64); Rela64 entries of 24 bytes with r_offset +0
// (u64), r_info +8 (u64; low u32 = type, next u32 = symbol index).
def SHENT: i32 = 64;
def SYMENT: i32 = 24;
def RELAENT: i32 = 24;
fn shnum(o: str) i32 = { return testenv.leu16(o, 60): i32; };
fn shoff(o: str, i: i32) i32 = {
return (testenv.leu64(o, 40): i32) + SHENT * i;
};
fn cstr(o: str, off: i32) str = {
let nb: []u8 = alloc([], 64u64)!;
let k: i32 = 0;
for (o[off + k] != 0u8) {
append(nb, o[off + k]);
k += 1;
};
return strings.frombytes(nb);
};
fn shname(o: str, i: i32) str = {
let strsh: i32 = shoff(o, testenv.leu16(o, 62): i32);
let stroff: i32 = testenv.leu64(o, strsh + 24): i32;
return cstr(o, stroff + (testenv.leu32(o, shoff(o, i)): i32));
};
fn findsection(o: str, name: str) i32 = {
let i: i32 = 0;
for (i < shnum(o)) {
if (testenv.same(shname(o, i), name)) { return i; };
i += 1;
};
return -1;
};
fn findsectiontype(o: str, ty: u64) i32 = {
let i: i32 = 0;
for (i < shnum(o)) {
if (testenv.leu32(o, shoff(o, i) + 4) == ty) { return i; };
i += 1;
};
return -1;
};
// Name of .symtab entry `symidx` through the sh_link strtab; "" when
// there is no symtab (SHT_SYMTAB == 2).
fn symname(o: str, symidx: i32) str = {
let ist: i32 = findsectiontype(o, 2u64);
if (ist < 0) { return ""; };
let sh: i32 = shoff(o, ist);
let symoff: i32 = testenv.leu64(o, sh + 24): i32;
let strsh: i32 = shoff(o, testenv.leu32(o, sh + 40): i32);
let stroff: i32 = testenv.leu64(o, strsh + 24): i32;
let e: i32 = symoff + SYMENT * symidx;
return cstr(o, stroff + (testenv.leu32(o, e): i32));
};
// Byte offset of the named Sym64 entry, or -1. Entry 0 is the
// reserved null symbol.
fn findsym(o: str, name: str) i32 = {
let ist: i32 = findsectiontype(o, 2u64);
if (ist < 0) { return -1; };
let sh: i32 = shoff(o, ist);
let symoff: i32 = testenv.leu64(o, sh + 24): i32;
let n: i32 = (testenv.leu64(o, sh + 32): i32) / SYMENT;
let i: i32 = 1;
for (i < n) {
if (testenv.same(symname(o, i), name)) {
return symoff + SYMENT * i;
};
i += 1;
};
return -1;
};
fn iself64(o: str) bool = {
if (o.len < 64) { return false; };
return o[0] == 0x7fu8 && o[1] == 0x45u8 && o[2] == 0x4cu8
&& o[3] == 0x46u8 && o[4] == 2u8;
};
// ---- elf64header (500) -------------------------------------------------
@test fn elf64header() void = {
let td: str = testenv.fresh();
let programs: []str = [
"fn main() i32 = { return 42; };",
"fn add(a: i32, b: i32) i32 = { return a + b; };",
"fn loop() i32 = { let i: i32 = 0; for (i < 10) { i += 1; }; return i; };",
"fn cmp(a: i32, b: i32) bool = { return a < b; };",
];
let i: i32 = 0;
for (i < 4) {
let stem: str = strings.concat(td, "/p", dec(i));
let src: str = strings.concat(stem, ".ww");
let asmf: str = strings.concat(stem, ".s");
let obj: str = strings.concat(stem, ".o");
testenv.writefile(src, strings.concat("package main;\n",
programs[i], "\n"));
let cav: []str = [testenv.driver("w6c"), "-o", asmf, src];
if (runcode(td, strings.concat("c", dec(i)), cav) != 0) {
fail("elf64header", strings.concat("w6c failed on ",
programs[i]));
};
let aav: []str = [testenv.driver("w6a"), "-o", obj, asmf];
if (runcode(td, strings.concat("a", dec(i)), aav) != 0) {
fail("elf64header", strings.concat("w6a failed on ",
programs[i]));
};
if (!iself64(testenv.readfile(obj))) {
fail("elf64header", strings.concat("not an ELF64: ",
programs[i]));
};
i += 1;
};
testenv.clean(td);
};
// ---- dataw (510) -------------------------------------------------------
@test fn dataw() void = {
let td: str = testenv.fresh();
let src: str = strings.concat(td, "/dataw.s");
let obj: str = strings.concat(td, "/dataw.o");
testenv.writefile(src, strings.concat(
"TEXT _start(SB),$0\n",
"\tMOVQ\t$0, AX\n",
"\tRET\n",
"DATAW counter(SB),\"\\x2a\\x00\\x00\\x00\\x00\\x00\\x00\\x00\"\n"));
let av: []str = [testenv.driver("w6a"), "-o", obj, src];
if (runcode(td, "dataw_a", av) != 0) {
fail("dataw", "w6a failed");
};
let o: str = testenv.readfile(obj);
// NULL, .text, .rela.text, .data, .symtab, .strtab, .shstrtab
if (shnum(o) != 7) {
fail("dataw", strings.concat("e_shnum=", dec(shnum(o)),
", want 7"));
};
let idx: i32 = findsection(o, ".data");
if (idx < 0) { fail("dataw", ".data section not found"); };
let sh: i32 = shoff(o, idx);
// SHT_PROGBITS == 1
if (testenv.leu32(o, sh + 4) != 1u64) {
fail("dataw", ".data sh_type != PROGBITS");
};
// SHF_WRITE|SHF_ALLOC == 0x3, SHF_EXECINSTR == 0x4
let fl: u64 = testenv.leu64(o, sh + 8);
if ((fl & 3u64) != 3u64) {
fail("dataw", ".data flags miss ALLOC|WRITE");
};
if ((fl & 4u64) != 0u64) {
fail("dataw", ".data is executable, want non-X");
};
if (testenv.leu64(o, sh + 32) != 8u64) {
fail("dataw", ".data size != 8");
};
let doff: i32 = testenv.leu64(o, sh + 24): i32;
if (o[doff] != 0x2au8) {
fail("dataw", ".data contents mismatch (LE i64 42)");
};
let k: i32 = 1;
for (k < 8) {
if (o[doff + k] != 0u8) {
fail("dataw", ".data contents mismatch (LE i64 42)");
};
k += 1;
};
let sym: i32 = findsym(o, "counter");
if (sym < 0) { fail("dataw", "symbol 'counter' not in .symtab"); };
if ((testenv.leu16(o, sym + 6): i32) != idx) {
fail("dataw", "'counter'.st_shndx is not the .data index");
};
if (testenv.leu64(o, sym + 8) != 0u64) {
fail("dataw", "'counter'.st_value != 0");
};
testenv.clean(td);
};
// ---- nodataw (510) -----------------------------------------------------
@test fn nodataw() void = {
let td: str = testenv.fresh();
let src: str = strings.concat(td, "/nodataw.s");
let obj: str = strings.concat(td, "/nodataw.o");
testenv.writefile(src, strings.concat(
"TEXT _start(SB),$0\n",
"\tMOVQ\t$0, AX\n",
"\tRET\n"));
let av: []str = [testenv.driver("w6a"), "-o", obj, src];
if (runcode(td, "nodataw_a", av) != 0) {
fail("nodataw", "w6a failed");
};
let o: str = testenv.readfile(obj);
// 991 (selfhost w6a .o byte-diff) relies on the legacy layout.
if (shnum(o) != 6) {
fail("nodataw", strings.concat("e_shnum=", dec(shnum(o)),
", want 6 (legacy)"));
};
if (findsection(o, ".data") >= 0) {
fail("nodataw", ".data section present, want absent");
};
testenv.clean(td);
};
// ---- datar (520) -------------------------------------------------------
@test fn datar() void = {
let td: str = testenv.fresh();
let src: str = strings.concat(td, "/datar.s");
let obj: str = strings.concat(td, "/datar.o");
let exe: str = strings.concat(td, "/datar.x");
testenv.writefile(src, strings.concat(
"TEXT _start,$0\n",
"\tMOVQ\t$1, AX\n",
"\tMOVQ\t$1, DI\n",
"\tMOVQ\tpair(SB), SI\n",
"\tMOVQ\t$5, DX\n",
"\tSYSCALL\n",
"\tMOVQ\t$60, AX\n",
"\tMOVQ\t$0, DI\n",
"\tSYSCALL\n",
"\n",
"DATAW pair(SB),\"\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00",
"\\x05\\x00\\x00\\x00\\x00\\x00\\x00\\x00\"\n",
"DATAR pair+0(SB),greeting(SB)\n",
"DATA greeting(SB),\"hello\"\n"));
let aav: []str = [testenv.driver("w6a"), "-o", obj, src];
if (runcode(td, "datar_a", aav) != 0) {
fail("datar", "w6a failed");
};
let o: str = testenv.readfile(obj);
let idx: i32 = findsection(o, ".rela.data");
if (idx < 0) { fail("datar", ".rela.data section missing"); };
let sh: i32 = shoff(o, idx);
// SHT_RELA == 4
if (testenv.leu32(o, sh + 4) != 4u64) {
fail("datar", ".rela.data sh_type != SHT_RELA");
};
// exactly one Rela64 entry
if (testenv.leu64(o, sh + 32) != RELAENT: u64) {
fail("datar", ".rela.data entry count != 1");
};
let ro: i32 = testenv.leu64(o, sh + 24): i32;
if (testenv.leu64(o, ro) != 0u64) {
fail("datar", "reloc offset != 0");
};
// R_X86_64_64 == 1
if (testenv.leu32(o, ro + 8) != 1u64) {
fail("datar", "reloc kind != R_X86_64_64");
};
if (!testenv.same(symname(o, testenv.leu32(o, ro + 12): i32),
"greeting")) {
fail("datar", "reloc symbol != greeting");
};
let lav: []str = [testenv.driver("w6l"), "-o", exe, obj];
if (runcode(td, "datar_l", lav) != 0) {
fail("datar", "w6l failed");
};
let rav: []str = [exe];
let co: testenv.commandout;
testenv.runcommand(td, td, "datar_run", rav, tmo(), &co);
if (co.termination != exec.termination.EXIT || co.code != 0) {
fail("datar", "exe exit != 0");
};
// the linker patched the .data slot with greeting's runtime VA
if (!testenv.same(co.stdout, "hello")) {
fail("datar", "stdout != 'hello'");
};
testenv.clean(td);
};

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@@ -1,63 +0,0 @@
/*
* 500_asm — assembler smoke. Drive w6c on a tiny program, feed the
* output to w6a, then read back the .o magic to confirm we produced
* a valid ELF64 relocatable object.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "wwtestpkg.h"
static int
run(const char *cmd)
{
return system(cmd);
}
int
main(void)
{
const char *bin = getenv("BIN");
if (!bin) bin = "out/bin";
char src[64], asmf[64], obj[64];
snprintf(src, sizeof src, "/tmp/wwt_%d.ww", getpid());
snprintf(asmf, sizeof asmf, "/tmp/wwt_%d.s", getpid());
snprintf(obj, sizeof obj, "/tmp/wwt_%d.o", getpid());
const char *programs[] = {
"fn main() i32 = { return 42; };",
"fn add(a: i32, b: i32) i32 = { return a + b; };",
"fn loop() i32 = { let i: i32 = 0; for (i < 10) { i += 1; }; return i; };",
"fn cmp(a: i32, b: i32) bool = { return a < b; };",
NULL
};
int n = 0, fail = 0;
for (int i = 0; programs[i]; i++, n++) {
FILE *f = fopen(src, "wb");
wwtest_fputs(programs[i], f);
fclose(f);
char cmd[512];
snprintf(cmd, sizeof cmd, "%s/w6c -o %s %s", bin, asmf, src);
if (run(cmd) != 0) { fprintf(stderr, "w6c fail: %s\n", programs[i]); fail++; continue; }
snprintf(cmd, sizeof cmd, "%s/w6a -o %s %s", bin, obj, asmf);
if (run(cmd) != 0) { fprintf(stderr, "w6a fail: %s\n", programs[i]); fail++; continue; }
FILE *of = fopen(obj, "rb");
if (of == NULL) { fail++; continue; }
unsigned char hdr[16];
size_t r = fread(hdr, 1, sizeof hdr, of);
fclose(of);
if (r != 16 || memcmp(hdr, "\x7f""ELF", 4) != 0
|| hdr[4] != 2 /* ELFCLASS64 */) {
fprintf(stderr, "not an ELF64: %s\n", programs[i]);
fail++;
}
}
unlink(src); unlink(asmf); unlink(obj);
if (fail) { fprintf(stderr, "%d/%d w6a tests failed\n", fail, n); return 1; }
printf("w6a: %d/%d ok\n", n, n);
return 0;
}

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@@ -1,284 +0,0 @@
/*
* 510_dataw — DATAW directive smoke. Assemble a tiny .s that uses
* DATAW and verify the resulting .o has a writable .data section
* containing the right bytes, with a symbol that points to it.
*
* Also confirms the no-DATAW path stays byte-identical to the
* pre-DATAW format (6 sections, no .data); the selfhost .o diff in
* 991 depends on that invariant.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdint.h>
#include <unistd.h>
#define SHT_PROGBITS 1
#define SHT_SYMTAB 2
#define SHF_WRITE 0x1
#define SHF_ALLOC 0x2
#define SHF_EXECINSTR 0x4
#pragma pack(push, 1)
typedef struct {
uint8_t e_ident[16];
uint16_t e_type, e_machine;
uint32_t e_version;
uint64_t e_entry, e_phoff, e_shoff;
uint32_t e_flags;
uint16_t e_ehsize, e_phentsize, e_phnum, e_shentsize, e_shnum, e_shstrndx;
} Ehdr;
typedef struct {
uint32_t sh_name, sh_type;
uint64_t sh_flags, sh_addr, sh_offset, sh_size;
uint32_t sh_link, sh_info;
uint64_t sh_addralign, sh_entsize;
} Shdr;
typedef struct {
uint32_t st_name;
uint8_t st_info, st_other;
uint16_t st_shndx;
uint64_t st_value, st_size;
} Sym64;
#pragma pack(pop)
static int
write_file(const char *path, const char *body)
{
FILE *f = fopen(path, "wb");
if (!f) return -1;
fputs(body, f);
fclose(f);
return 0;
}
static int
slurp(const char *path, uint8_t **out, size_t *outn)
{
FILE *f = fopen(path, "rb");
if (!f) return -1;
fseek(f, 0, SEEK_END);
long n = ftell(f);
fseek(f, 0, SEEK_SET);
uint8_t *b = malloc((size_t)n);
if (fread(b, 1, (size_t)n, f) != (size_t)n) {
free(b);
fclose(f);
return -1;
}
fclose(f);
*out = b;
*outn = (size_t)n;
return 0;
}
/* Find the section with the given name. Returns index, or -1. */
static int
find_section(const uint8_t *buf, const char *name)
{
const Ehdr *eh = (const Ehdr *)buf;
const Shdr *sh = (const Shdr *)(buf + eh->e_shoff);
const char *shstr = (const char *)(buf + sh[eh->e_shstrndx].sh_offset);
for (uint16_t i = 0; i < eh->e_shnum; i++) {
if (strcmp(shstr + sh[i].sh_name, name) == 0)
return (int)i;
}
return -1;
}
/* Find a symbol by name in the .symtab. Returns pointer, or NULL. */
static const Sym64 *
find_symbol(const uint8_t *buf, const char *name)
{
const Ehdr *eh = (const Ehdr *)buf;
const Shdr *sh = (const Shdr *)(buf + eh->e_shoff);
int idx_symtab = -1;
for (uint16_t i = 0; i < eh->e_shnum; i++)
if (sh[i].sh_type == SHT_SYMTAB) { idx_symtab = i; break; }
if (idx_symtab < 0) return NULL;
int idx_strtab = (int)sh[idx_symtab].sh_link;
const Sym64 *syms = (const Sym64 *)(buf + sh[idx_symtab].sh_offset);
uint64_t nsyms = sh[idx_symtab].sh_size / sizeof(Sym64);
const char *str = (const char *)(buf + sh[idx_strtab].sh_offset);
for (uint64_t i = 1; i < nsyms; i++) {
if (strcmp(str + syms[i].st_name, name) == 0)
return &syms[i];
}
return NULL;
}
static int
test_dataw_emits_writable_section(const char *bin)
{
char src[64], obj[64];
snprintf(src, sizeof src, "/tmp/wwt_dataw_%d.s", getpid());
snprintf(obj, sizeof obj, "/tmp/wwt_dataw_%d.o", getpid());
/* Hand-crafted .s: one writable data symbol holding 8 bytes (the
* little-endian encoding of the i64 42) plus a trivial TEXT so
* the assembler has something in .text to anchor. */
const char *body =
"TEXT _start(SB),$0\n"
"\tMOVQ\t$0, AX\n"
"\tRET\n"
"DATAW counter(SB),\"\\x2a\\x00\\x00\\x00\\x00\\x00\\x00\\x00\"\n";
if (write_file(src, body) < 0) {
fprintf(stderr, "dataw: cannot write %s\n", src);
return -1;
}
char cmd[512];
snprintf(cmd, sizeof cmd, "%s/w6a -o %s %s", bin, obj, src);
if (system(cmd) != 0) {
fprintf(stderr, "dataw: w6a failed\n");
unlink(src);
return -1;
}
uint8_t *buf = NULL;
size_t n = 0;
if (slurp(obj, &buf, &n) < 0) {
fprintf(stderr, "dataw: cannot read .o\n");
unlink(src); unlink(obj);
return -1;
}
const Ehdr *eh = (const Ehdr *)buf;
int rc = 0;
/* Expect 7 sections: NULL, .text, .rela.text, .data, .symtab, .strtab, .shstrtab. */
if (eh->e_shnum != 7) {
fprintf(stderr, "dataw: e_shnum=%u, want 7\n", eh->e_shnum);
rc = -1;
}
int idx_data = find_section(buf, ".data");
if (idx_data < 0) {
fprintf(stderr, "dataw: .data section not found\n");
rc = -1;
goto out;
}
const Shdr *sh = (const Shdr *)(buf + eh->e_shoff);
const Shdr *sd = &sh[idx_data];
if (sd->sh_type != SHT_PROGBITS) {
fprintf(stderr, "dataw: .data sh_type=%u, want PROGBITS\n", sd->sh_type);
rc = -1;
}
if ((sd->sh_flags & (SHF_ALLOC | SHF_WRITE)) != (SHF_ALLOC | SHF_WRITE)) {
fprintf(stderr, "dataw: .data flags=0x%lx, want ALLOC|WRITE\n",
(unsigned long)sd->sh_flags);
rc = -1;
}
if ((sd->sh_flags & SHF_EXECINSTR) != 0) {
fprintf(stderr, "dataw: .data is executable, want non-X\n");
rc = -1;
}
if (sd->sh_size != 8) {
fprintf(stderr, "dataw: .data size=%lu, want 8\n",
(unsigned long)sd->sh_size);
rc = -1;
}
/* Verify the bytes themselves match the LE i64 42 we wrote. */
const uint8_t *db = buf + sd->sh_offset;
uint8_t want[8] = { 0x2a, 0, 0, 0, 0, 0, 0, 0 };
if (memcmp(db, want, 8) != 0) {
fprintf(stderr, "dataw: .data contents mismatch\n");
rc = -1;
}
const Sym64 *s = find_symbol(buf, "counter");
if (s == NULL) {
fprintf(stderr, "dataw: symbol 'counter' not in .symtab\n");
rc = -1;
goto out;
}
if ((int)s->st_shndx != idx_data) {
fprintf(stderr, "dataw: 'counter'.st_shndx=%u, want %d (.data)\n",
s->st_shndx, idx_data);
rc = -1;
}
if (s->st_value != 0) {
fprintf(stderr, "dataw: 'counter'.st_value=%lu, want 0\n",
(unsigned long)s->st_value);
rc = -1;
}
out:
free(buf);
unlink(src);
unlink(obj);
return rc;
}
static int
test_no_dataw_keeps_legacy_layout(const char *bin)
{
char src[64], obj[64];
snprintf(src, sizeof src, "/tmp/wwt_nodataw_%d.s", getpid());
snprintf(obj, sizeof obj, "/tmp/wwt_nodataw_%d.o", getpid());
/* A .s without any DATAW must still produce the legacy 6-section
* layout. Test 991 (selfhost .o byte-diff) relies on this. */
const char *body =
"TEXT _start(SB),$0\n"
"\tMOVQ\t$0, AX\n"
"\tRET\n";
if (write_file(src, body) < 0) {
fprintf(stderr, "nodataw: cannot write %s\n", src);
return -1;
}
char cmd[512];
snprintf(cmd, sizeof cmd, "%s/w6a -o %s %s", bin, obj, src);
if (system(cmd) != 0) {
fprintf(stderr, "nodataw: w6a failed\n");
unlink(src);
return -1;
}
uint8_t *buf = NULL;
size_t n = 0;
if (slurp(obj, &buf, &n) < 0) {
fprintf(stderr, "nodataw: cannot read .o\n");
unlink(src); unlink(obj);
return -1;
}
const Ehdr *eh = (const Ehdr *)buf;
int rc = 0;
if (eh->e_shnum != 6) {
fprintf(stderr, "nodataw: e_shnum=%u, want 6 (legacy)\n",
eh->e_shnum);
rc = -1;
}
if (find_section(buf, ".data") >= 0) {
fprintf(stderr, "nodataw: .data section present, want absent\n");
rc = -1;
}
free(buf);
unlink(src);
unlink(obj);
return rc;
}
int
main(void)
{
const char *bin = getenv("BIN");
if (!bin) bin = "out/bin";
int fail = 0;
if (test_dataw_emits_writable_section(bin) != 0) fail++;
if (test_no_dataw_keeps_legacy_layout(bin) != 0) fail++;
if (fail) {
fprintf(stderr, "dataw: %d/2 subtests failed\n", fail);
return 1;
}
printf("dataw: 2/2 ok\n");
return 0;
}

View File

@@ -1,194 +0,0 @@
/*
* 520_datar — DATAR reloc smoke. Assemble + link a tiny .s that
* uses DATAR to patch a .data slot with a symbol's runtime VA,
* then run the binary and confirm the linker filled the slot
* correctly: the program prints "hello" via the relocated pointer
* and exits 0.
*
* Also confirms the .o has a `.rela.data` section with one
* R_X86_64_64 entry against the expected symbol — catches
* regressions where the asm emits DATAR but obj.c doesn't reach
* the writable-data reloc path.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdint.h>
#include <unistd.h>
#include <sys/wait.h>
#define SHT_RELA 4
#define R_X86_64_64 1
#pragma pack(push, 1)
typedef struct {
uint8_t e_ident[16];
uint16_t e_type, e_machine;
uint32_t e_version;
uint64_t e_entry, e_phoff, e_shoff;
uint32_t e_flags;
uint16_t e_ehsize, e_phentsize, e_phnum, e_shentsize, e_shnum, e_shstrndx;
} Ehdr;
typedef struct {
uint32_t sh_name, sh_type;
uint64_t sh_flags, sh_addr, sh_offset, sh_size;
uint32_t sh_link, sh_info;
uint64_t sh_addralign, sh_entsize;
} Shdr;
typedef struct {
uint64_t r_offset;
uint64_t r_info;
int64_t r_addend;
} Rela64;
#pragma pack(pop)
static int
run_exit(const char *cmd)
{
int rc = system(cmd);
if (rc == -1) return -1;
if (WIFEXITED(rc)) return WEXITSTATUS(rc);
return -1;
}
static int
slurp(const char *path, uint8_t **out, size_t *outn)
{
FILE *f = fopen(path, "rb");
if (!f) return -1;
fseek(f, 0, SEEK_END);
long n = ftell(f);
fseek(f, 0, SEEK_SET);
uint8_t *b = malloc((size_t)n);
if (fread(b, 1, (size_t)n, f) != (size_t)n) {
free(b); fclose(f); return -1;
}
fclose(f);
*out = b; *outn = (size_t)n;
return 0;
}
static const char *prog =
"TEXT _start,$0\n"
"\tMOVQ\t$1, AX\n" /* write syscall */
"\tMOVQ\t$1, DI\n" /* fd = 1 (stdout) */
"\tMOVQ\tpair(SB), SI\n" /* ptr (relocated) */
"\tMOVQ\t$5, DX\n" /* count = 5 */
"\tSYSCALL\n"
"\tMOVQ\t$60, AX\n" /* exit */
"\tMOVQ\t$0, DI\n"
"\tSYSCALL\n"
"\n"
"DATAW pair(SB),\"\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00"
"\\x05\\x00\\x00\\x00\\x00\\x00\\x00\\x00\"\n"
"DATAR pair+0(SB),greeting(SB)\n"
"DATA greeting(SB),\"hello\"\n";
int
main(void)
{
const char *bin = getenv("BIN");
if (!bin) bin = "out/bin";
char src[64], obj[64], exe[64], cmd[1024];
snprintf(src, sizeof src, "/tmp/wwt_datar_%d.s", getpid());
snprintf(obj, sizeof obj, "/tmp/wwt_datar_%d.o", getpid());
snprintf(exe, sizeof exe, "/tmp/wwt_datar_%d.x", getpid());
FILE *f = fopen(src, "wb");
if (!f) return 1;
fputs(prog, f);
fclose(f);
snprintf(cmd, sizeof cmd, "%s/w6a -o %s %s", bin, obj, src);
if (system(cmd) != 0) {
fprintf(stderr, "datar: w6a failed\n");
return 1;
}
int fail = 0;
/* Inspect the .o: there must be a .rela.data section with one
* R_X86_64_64 entry against `greeting`. */
uint8_t *buf = NULL; size_t n = 0;
if (slurp(obj, &buf, &n) < 0) {
fprintf(stderr, "datar: cannot read .o\n");
fail++;
goto run_step;
}
const Ehdr *eh = (const Ehdr *)buf;
const Shdr *sh = (const Shdr *)(buf + eh->e_shoff);
const char *shstr = (const char *)(buf + sh[eh->e_shstrndx].sh_offset);
int idx_relad = -1, idx_strtab = -1, idx_symtab = -1;
for (uint16_t i = 0; i < eh->e_shnum; i++) {
const char *nm = shstr + sh[i].sh_name;
if (sh[i].sh_type == SHT_RELA && strcmp(nm, ".rela.data") == 0)
idx_relad = i;
if (sh[i].sh_type == 2 /* SHT_SYMTAB */)
idx_symtab = i;
}
if (idx_symtab >= 0)
idx_strtab = (int)sh[idx_symtab].sh_link;
if (idx_relad < 0) {
fprintf(stderr, "datar: .rela.data section missing\n");
fail++;
} else {
const Rela64 *rd = (const Rela64 *)(buf + sh[idx_relad].sh_offset);
uint64_t nrel = sh[idx_relad].sh_size / sizeof(Rela64);
if (nrel != 1) {
fprintf(stderr, "datar: .rela.data has %lu entries, want 1\n",
(unsigned long)nrel);
fail++;
} else {
uint32_t kind = (uint32_t)(rd[0].r_info & 0xffffffff);
if (kind != R_X86_64_64) {
fprintf(stderr, "datar: reloc kind %u, want %d\n",
kind, R_X86_64_64);
fail++;
}
if (rd[0].r_offset != 0) {
fprintf(stderr, "datar: reloc offset %lu, want 0\n",
(unsigned long)rd[0].r_offset);
fail++;
}
}
}
free(buf);
run_step:
snprintf(cmd, sizeof cmd, "%s/w6l -o %s %s", bin, exe, obj);
if (system(cmd) != 0) {
fprintf(stderr, "datar: w6l failed\n");
unlink(src); unlink(obj);
return 1;
}
/* Run: should print "hello" and exit 0. We pipe stdout to a
* tmp file and check both the output and the exit code. */
char outf[64];
snprintf(outf, sizeof outf, "/tmp/wwt_datar_%d.out", getpid());
snprintf(cmd, sizeof cmd, "%s > %s", exe, outf);
int rc = run_exit(cmd);
if (rc != 0) {
fprintf(stderr, "datar: exit=%d, want 0\n", rc);
fail++;
}
uint8_t *out = NULL; size_t on = 0;
if (slurp(outf, &out, &on) < 0 || on != 5
|| memcmp(out, "hello", 5) != 0) {
fprintf(stderr, "datar: stdout != 'hello'\n");
fail++;
}
free(out);
unlink(src); unlink(obj); unlink(exe); unlink(outf);
if (fail) {
fprintf(stderr, "datar: %d check(s) failed\n", fail);
return 1;
}
printf("datar: ok\n");
(void)idx_strtab;
return 0;
}