re: an ISL symbol operand is a (tag, index) pair — and two more names withdrawn

Verified rather than adopted: a subagent proposed that every even operand
slot is a type tag. Measured, the strong form is false and a precise form is
true.

TRUE: a SYMBOL operand is two words, a tag holding the constant 1 followed
by the index. Slot 0 is the integer 1 in 19899/19899 calls whose slot 4 is a
unit; slot 8 is tag-shaped in 100% of calls for every built-in taking a
second unit; slot 16 is 1 in 152/152 for built-in 128, the only one taking a
third. The 24 built-ins whose slot 0 is NOT the constant are exactly those
taking no symbol there. This explains the unit slots 4/12/20 rather than
replacing them.

FALSE as stated: slot 8 is a bare double for built-ins 4, 20, 24, 26, 28,
29, 90, 106 and 127, and built-in 75 carries five bare indices at 0/4/8/12/16
with no tags at all. Each built-in has a fixed signature and is 100%
self-consistent; none of the 34 with >=20 sites mixes the two.

Symbol table 1 has three types -- 1 routes (1362), 6 messages (2247), 7
effects (81) -- and its operand slots are type-pure, measured the same way.
Resolving them makes listings say what the script means:
`request_script_message(MSG_VOICE_D_257, ...)`, a fourth independent
confirmation of that name. Slots 24@4, 46@12 and 114@4 resolve 100% but MIX
types 6 and 1, so they are left unresolved rather than guessed.

Two more names withdrawn, neither replaced:
* 88 `camera_at` -- ZERO call sites in all 28 stages; never testable.
* 90 `camera_at_route` -- 8 sites, all Stage 02 phase 3, first operand is
  symtab-1 type 7 `eff_n0071`, an EFFECT name, in 8/8, with a per-missile
  Route_ADT301..308_p3M at slot 20. Not aimed at a camera.

Left unnamed on purpose: replacing a guessed name with another guess is how
the three names corrected earlier today went wrong.

Also flagged: 115 `named_event`'s only symbol operand is an eff_* name in
84/84 sites, so that name is suspect too. Not renamed pending a handler read.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PMRJjbxLqZtsb5Vb7KunPE
This commit is contained in:
Sylpheed RE agent
2026-08-25 22:51:07 +00:00
parent cb1b634adf
commit 009bca880e
4 changed files with 124 additions and 11 deletions

View File

@@ -88,7 +88,13 @@ BUILTIN = {
48: 'squadron_escort', 52: 'play_stream', 53: 'sound_busy', 54: 'stop_sound',
56: 'unit_relation', 59: 'fade_sound', 62: 'FORCE_END_PHASE', 64: 'request_script_message',
69: 'unit_state', 70: 'unit_alive', 72: 'group_ratio_pct', 73: 'timer_start',
74: 'timer_limit', 88: 'camera_at', 90: 'camera_at_route',
74: 'timer_limit',
# ❌ 88 'camera_at' and 90 'camera_at_route' WITHDRAWN. 88 has ZERO call
# sites in all 28 stages, so its name was never testable. 90 has exactly 8,
# all in Stage 02 phase 3 (the cruise-missile act), and its first operand
# resolves to symbol-table-1 type 7 -- `eff_n0071`, an EFFECT name -- in
# 8/8, with a per-missile `Route_ADT30N_p3M` at slot 20. Whatever it does,
# it is not aimed at a camera. Left unnamed rather than renamed on a guess.
93: 'clear_flag', 94: 'is_engaged', 95: 'unit_hp_pct', 100: 'reset_phase_threads',
102: 'prompt_yes_no', 109: 'set_unit_flags', 115: 'named_event',
120: 'wait_cmds_drained', 123: 'timer_resume', 124: 'timer_stop',
@@ -154,6 +160,46 @@ UNIT_ARG2 = {2, 18, 47, 48, 56, 79, 95, 128} # a SECOND unit index at blob[12
UNIT_ARG3 = {128} # and a third at blob[20]
UNIT_SLOTS = {4: UNIT_ARG, 12: UNIT_ARG2, 20: UNIT_ARG3}
# WHY the unit indices sit at 4/12/20 and never at 0/8/16: a **symbol operand is
# a two-word pair** -- a tag word holding the constant 1, then the index. The
# tag is not data, so printing it puts a meaningless leading `0x1` in front of
# every unit predicate.
#
# Measured over all 28 stages:
# * slot 0 is the integer 1 in 19899 / 19899 calls whose slot 4 is a unit;
# * slot 8 is tag-shaped in 100% of calls for every built-in taking a second
# unit, and slot 16 is the constant 1 in 152/152 for built-in 128, the only
# one taking a third;
# * 24 built-ins have a slot 0 that is NOT the constant -- and every one of
# them takes no symbol at slot 4 (`start_coroutine` a code offset, `wait_s`
# a double, `set_flag` an index).
#
# The tag does NOT generalise to "every even slot is a tag": slot 8 is a bare
# double for built-ins 4, 20, 24, 26, 28, 29, 90, 106 and 127, and built-in 75
# carries five bare symbol indices at 0/4/8/12/16 with no tags at all. Each
# built-in has a fixed signature and is 100% consistent with itself; none mixes.
TAG_SLOTS = {slot - 4 for slot in UNIT_SLOTS}
# Symbol table 1 holds three types, and its slots were measured the same way as
# the unit slots (every observed value resolves, >=5 distinct values, and the
# resolved type is pure):
# type 1 (1362 entries) `Route_*` names
# type 6 (2247) message / objective names
# type 7 (81) `eff_*` effect names
SYM1_SLOTS = {
0: {64, 75, 115}, # 64 & 75 type 6; 115 type 7
4: {75, 136},
8: {75},
12: {2, 3, 7, 16, 19, 25, 75, 108, 143},
16: {75},
20: {90},
24: {48},
28: {128},
}
# Deliberately NOT listed: built-ins 24@4, 46@12 and 114@4 resolve 100% but mix
# type 6 and type 1, so the slot's meaning is not one thing. Recorded rather
# than guessed at.
# Symbol table 2 holds TWO entity types: type 2 (1160 entries disc-wide) and
# type 8 (249). They are not interchangeable -- built-ins 95 and 128 take a
# type-2 unit at slot 4 and, at slot 12, an operand that is type 8 in 100% of
@@ -161,7 +207,7 @@ UNIT_SLOTS = {4: UNIT_ARG, 12: UNIT_ARG2, 20: UNIT_ARG3}
# not yet established.
def dis(b, off, count=40, code_base=0x24, args=True, sym2=None):
def dis(b, off, count=40, code_base=0x24, args=True, sym2=None, sym1=None):
out = []
staged = {} # local[] slot -> last value staged into it
pending = None # value most recently put in special[0]
@@ -221,15 +267,22 @@ def dis(b, off, count=40, code_base=0x24, args=True, sym2=None):
extra = ' %s' % BUILTIN.get(words[0], 'builtin%d' % words[0])
if args and staged:
parts = []
# The tag word in front of a symbol operand is not an argument.
tags = {slot - 4 for slot, ids in UNIT_SLOTS.items()
if words[0] in ids and slot in staged}
for slot, v in sorted(staged.items()):
if slot in tags and v == 1:
continue
txt = ('0x%X' % v) if isinstance(v, int) else v
# Resolve only a slot that is declared a unit index AND
# whose value really is one -- a resolver that invents a
# name for a non-index is worse than one that prints the
# raw number.
# Resolve only a slot that is declared an index AND whose
# value really is one -- a resolver that invents a name for
# a non-index is worse than one that prints the raw number.
if (sym2 and words[0] in UNIT_SLOTS.get(slot, ())
and isinstance(v, int) and v in sym2):
txt = sym2[v][1]
elif (sym1 and words[0] in SYM1_SLOTS.get(slot, ())
and isinstance(v, int) and v in sym1):
txt = sym1[v][1]
parts.append(txt)
extra += '(' + ', '.join(parts) + ')'
staged = {}

View File

@@ -27,7 +27,7 @@ def census(b):
def emit_calls(b, path):
cs, h = census(b)
s2 = isl.symbols(b, 2)
s1, s2 = isl.symbols(b, 1), isl.symbols(b, 2)
print('# %s — ISL disassembly artefacts' % path)
print()
print('Generated by `tools/re-capture/isl_report.py calls`.')
@@ -57,7 +57,7 @@ def emit_calls(b, path):
target = [off for off, bid, _ in cs if bid == 6][0]
start = isl.resync(b, target)
print('resync from 0x%X' % start)
for line in isl.dis(b, start, 64, code_base=0x24, sym2=s2):
for line in isl.dis(b, start, 64, code_base=0x24, sym2=s2, sym1=s1):
print(line)