w6a+w6l: DATAR directive for absolute-address relocs in .data

Unblock literal initialisers for str/slice/struct globals by wiring
an R_X86_64_64 relocation kind through both assembler and static
linker.

w6a:
  - new A_DATAR directive, syntax `DATAR slot+off(SB),target(SB)`,
    records an R_X86_64_64 reloc at slot+off in .data pointing at
    target. The slot must be pre-defined by a prior DATAW;
  - parse_operand learned the `name+disp(SB)` shape so the slot's
    byte offset can be addressed explicitly;
  - Areloc carries a `section` flag (0=.text / 1=.data) and obj.c
    splits the reloc list into .rela.text and .rela.data, emitting
    the latter conditionally with sh_info pointing at .data.

w6l:
  - Lrel grows the same `section` flag; obj.c loads `.rela.data`
    sections into the global reloc list with offsets shifted by
    each input's data_off;
  - pass.c handles R_X86_64_64: target VA is data_va+sym.val for
    in_data symbols (else text_va+sym.val), addend is added, and
    the 8-byte slot is patched in l->data (or l->text).

Inputs without DATAR are unaffected — bootstrap, 991 (selfhost .o
diff) and 992 (selfhost exe diff) keep their byte-identical
output. 520_datar covers the new path: asm a DATAW+DATAR pair,
verify .rela.data has exactly one R_X86_64_64 entry, link, run,
confirm the relocated pointer feeds a 5-byte write that prints
"hello".

Selfhost mirror + w6c emission for str/slice/struct literal init
land in follow-ups.
This commit is contained in:
2026-05-12 12:45:11 +09:00
parent 00d1120441
commit d998425391
11 changed files with 353 additions and 21 deletions

View File

@@ -210,8 +210,8 @@ $(BIN) $(LIB) $(OBJ)/wcc $(OBJ)/ww $(OBJ)/wwdump $(OBJ)/w6c $(OBJ)/w6a $(OBJ)/w6
# ---- tests -------------------------------------------------------------
# Each phase adds a $(BIN)/test_<name> target; the runner walks them.
TESTS = $(BIN)/test_smoke $(BIN)/test_lex $(BIN)/test_parse $(BIN)/test_check \
$(BIN)/test_w6c $(BIN)/test_w6a $(BIN)/test_dataw $(BIN)/test_w6l \
$(BIN)/test_data_link \
$(BIN)/test_w6c $(BIN)/test_w6a $(BIN)/test_dataw $(BIN)/test_datar \
$(BIN)/test_w6l $(BIN)/test_data_link \
$(BIN)/test_arch \
$(BIN)/test_e2e $(BIN)/test_ffi $(BIN)/test_dyn $(BIN)/test_stdlib \
$(BIN)/test_at_test $(BIN)/test_let_global \
@@ -240,6 +240,9 @@ $(BIN)/test_w6a: test/wcc/500_w6a.c $(BIN)/w6c $(BIN)/w6a | $(BIN)
$(BIN)/test_dataw: test/wcc/510_dataw.c $(BIN)/w6a | $(BIN)
$(CC) $(CFLAGS) -o $@ $<
$(BIN)/test_datar: test/wcc/520_datar.c $(BIN)/w6a $(BIN)/w6l | $(BIN)
$(CC) $(CFLAGS) -o $@ $<
$(BIN)/test_w6l: test/wcc/600_w6l.c $(BIN)/w6c $(BIN)/w6a $(BIN)/w6l | $(BIN)
$(CC) $(CFLAGS) -o $@ $<