Hojun-Cho/ww
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

test: regression lock for struct-ABI size formula (#78 lock)

Browse Source 
Project #78 was ken-flagged: cstage folded size(struct{i32,i32,i32}) to
12 (cmd/wcc/check.c:760, `(off + maxalign - 1) & ~(maxalign - 1)`) while
wwstage walked a slot-padded fsz ladder and yielded 16. The two
checkers ran different layout formulas. d4e500f (#169) closed the
cgen ABI half by introducing structabisize and walking it via per-
field tinfo.align; 39f9267 + 66a91c8 converged the remaining cgen
sites that had picked the slot-padded number. Verified at the size(T)
fold and the .s byte-id on every layout-edge shape.

Add 762_struct_abi_size.c (6 table rows) to lock the closure. Each
row carries a (sz, aln) field table; the expected size is computed in
C via the Hare layout formula (rule 13: no hardcoded size literals —
a formula bump lands in compute_expected and every row tracks). Both
gates run per row: a runtime check that `return size(T): i32` matches
the computed expected on both stages (catches a fold drift), and a
w6c vs w6c_ww .s byte-id (catches a cgen-ABI walker drift even when
the fold still matches — the two walkers are independent SSoTs).

Rows target maxalign edges:

  i32_x3_maxalign4          #78 canonical, natural==ABI==12
  i32_i32_i64_lead_narrow   maxalign 8, narrow lead, ABI 16
  i64_i32_i32_sub8_tail     #169 sub-8 tail, ABI 16 (the round-up)
  i16_x3_maxalign2          maxalign 2, natural==ABI==6
  i32_i32_i64_mid_align     mid-record align step explicit
  i64_x3_natural_24         all 8-wide, natural==ABI==24

GATE POLARITY: this file must stay GREEN. A red here means either
d4e500f reverted, or one of the two layout walkers (check.c:760 /
check.ww:958 / cgen.c struct_arg_size / cgenutil.ww structabisize)
drifted from the formula.
This commit is contained in:
Hojun-Cho
2026-05-28 16:54:08 +09:00
parent 276708f9d9
commit 098b58d15c
2 changed files with 293 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

7
Makefile
View File

@@ -312,6 +312,7 @@ TESTS = $(BIN)/test_smoke $(BIN)/test_lex $(BIN)/test_parse $(BIN)/test_check \
$(BIN)/test_check_enum_fold \
$(BIN)/test_def_widen_const \
$(BIN)/test_inferred_struct_arg_push \
$(BIN)/test_struct_abi_size \
$(BIN)/test_use_promote_alias \
$(BIN)/test_field_signed $(BIN)/test_frame_argcount \
$(BIN)/test_selfhost $(BIN)/test_w6a_ww $(BIN)/test_w6l_ww \
@@ -591,6 +592,12 @@ $(BIN)/test_inferred_struct_arg_push: test/wcc/761_inferred_struct_arg_push.c \
$(LIB)/libwwrt.a | $(BIN)
$(CC) $(CFLAGS) -o $@ $<
$(BIN)/test_struct_abi_size: test/wcc/762_struct_abi_size.c \
$(BIN)/ww $(BIN)/w6c $(BIN)/w6a $(BIN)/w6l \
$(BIN)/ww_ww $(BIN)/w6c_ww $(BIN)/w6a_ww $(BIN)/w6l_ww \
$(LIB)/libwwrt.a | $(BIN)
$(CC) $(CFLAGS) -o $@ $<
$(BIN)/test_arrlit_str_full: test/wcc/711_arrlit_str_full.c \
$(BIN)/ww $(BIN)/w6c $(BIN)/w6a $(BIN)/w6l \
$(BIN)/ww_ww $(BIN)/w6c_ww $(BIN)/w6a_ww $(BIN)/w6l_ww \