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Drew T
9f61cd33c5
The two functions the roadmap has carried as PERMANENT WALLS since Phase 24 are matched in all 138
overlays. Neither needed a siege. Both matched from drafts ALREADY ON DISK.
func_80178004 165 ins x 138 = 22,770 Phase 26: Fable5, ~477k tokens, "intrinsic 3-integer
regalloc wall". THREE stored drafts report match_one
MATCH today; one banked first try, no new work.
func_801412A8 198 ins x 138 = 27,324 close=29/110 since Phase 24. Matched from 1 of 31 stored
drafts + the §37/§124 alias.
WHY func_801412A8 LOOKED INTRINSIC (worth understanding — match_one is structurally blind to it):
the TU declares `extern int func_801412A8(int,int,int,int,int,int)` and its callers USE the return
(`param_1 = func_801412A8(...)`), while the byte-true definition is
`Prim_1412A8 *(Prim_1412A8 *, int, int, int, u16, u16)`. Narrow params cannot agree with an `int`
prototype and the no-prototype escape is illegal once a param promotes, so NEITHER side can move --
and the resulting byte difference is in the CALLERS, which match_one never compiles. The §37/§124
def-side asm-label alias decouples them: the TU decl keeps governing the call sites (codegen
untouched), the definition keeps its byte-true signature.
THEN PROPAGATION RETURNED 0/137 TWICE, both times a missing TYPE, not codegen:
family_remap's `_carry_macros` carries file-scope #defines but (a) NOT typedefs, and (b) is NOT
TRANSITIVE -- it brought addPrim_1412A8 and stopped, though that macro calls setaddr/getaddr and
getaddr casts to PTag_1412A8. Lifted Env_1412A8 / PTag_1412A8 / Prim_1412A8 + OT/getaddr/setaddr
into src/shared/engine_types.h (inside the include guard) -> 137/137, 0 failed.
MY ERROR, CAUGHT BY THE GATE: I lifted the typedefs but did not STRIP them from ov_SC01_077.c, so
they were declared twice and gcc-2.7.2 rejects a repeated typedef even when identical -- the lesson
already recorded at the foot of engine_types.h. R22 came back 139/140 with [FAIL] ov_SC01_077 (the
exemplar's own overlay). Stripped, re-verified, 140/140. A proper lift strips the source;
build_engine_types --strip does both and I did it by hand.
Also a measurement error worth recording: I checked whether the draft defined Prim_1412A8 with a
plain `grep -c` -- which matches inside `addPrim_1412A8` -- and briefly concluded the carry worked.
Substring false positive; the same shape as reading a `return` as a declaration.
VERIFIED: make clean && make extract-all && make check-all -> 140 passed, 0 failed of 140.
Fleet 12432941 -> 12483035 instr (+50,094 -- EXACTLY the two giants x138); fn-count +276;
instr-weighted 94.5% -> 94.8%. audit-digest OK. 0 NON_MATCHING (G4).
THE RULE THIS BUYS: re-measure a wall before respecting it, and SCAN every stored draft rather than
sampling (my first pass checked 8 of 31 and reported "closeness 40" for a function whose MATCH was
in the 9th). Four minutes of re-measurement was worth 50,094 instructions.