First positive result of the loader hunt, and it exists only because of the
control that two commits ago I said was missing.
Across 2,323 level-0 functions of at least 128 bytes -- extents from the decomp's
functions.tsv -- the immediate 0x00c0, which is moby_classes.offset, appears in
394 functions. Every value adjacent to it appears in 1 to 14.
0xb8:8 0xb9:2 0xba:2 0xbb:2 0xbc:3 0xbd:5 0xbe:5 0xbf:3
0xc1:3 0xc2:3 0xc3:2 0xc4:1 0xc5:2 0xc6:3 0xc7:1 0xc8:14
This is what 27891ce was asking for. 0xc0 is small and small immediates are
common -- 17,699 occurrences across the program, against 200,784 for 0x0001 -- so
the raw frequency was worthless. The neighbours have the same magnitude and none
of the frequency, which is the only reason 394 means anything rather than being an
artifact of the value being short.
A second control points the other way, so the two bracket it: the other five
level-0 chunk offsets are larger values and are referenced 0 to 2 times each.
Shrub_classes 1, tfrag_textures 2, moby_textures 2, tie_textures 0, shrub_textures
2. The chunk offsets a loader would use are referenced about once. moby_classes is
referenced 394 times. The program leans on this constant heavily.
The previous commit's 410 candidates were not a shortlist. These 394 are, because
the number is now separated from magnitude rather than merely stated.
WHAT THIS DOES NOT SAY
An immediate appearing in a function is not proof the chunk is READ there. It is
proof the constant is used, which is the claim the test asserts and the only claim
it makes. It does not say which of the 394 is the loader, or that the loader is
among them. Stated plainly because the 394 is the kind of number that gets
quoted without its caveat and then built on.
Also measured, negative: zero functions contain both the moby_classes and
tie_classes offsets, so nothing indexes both chunk tables by immediate. The moby
loader does not reach the tie table the same way, if it reaches it at all.
Boundaries: level 0 only, "level 0" meaning the function's first listed place is
level 00, and a 128-byte size floor -- 59957a0 recorded 20-byte "functions" that
are mis-bound extents.
283 passing with the disc present (23 + 19 + 63 + 156 + 22; disc binary 35.23s),
clippy clean.
ReaperOfVeriod
3ea5ab799f