It did its job -- it is what identified res - rtime == 128 as the constant behind
the Assassin's Creed hang -- and what it costs now is an atomic increment on a
shared static every time any conditional store fails, on every PPU thread. That is
cross-core traffic on the hot path of every guest atomic, for a question that has
been answered.
The measurement it produced is kept in the comment above the fix, which is the part
worth having.
Three fixes found while testing Assassin's Creed on a Turnip device.
fp16 was off on every Turnip install regardless of driver age. The gate that
re-enables it compares driverVersion against 512.676.53, which is QUALCOMM'S
numbering; is_ADRENO() is true for Turnip as well, and Turnip reports Mesa's
scheme -- 25.99.99 on an 8 Gen 2 -- which packs to a far smaller integer and can
never pass. So the log said "All float16_t arithmetic will be emulated with
float32_t" on the configuration these handhelds actually ship in.
It should not have been gated for Turnip at all. The failure being worked around
is Qualcomm's shader compiler rejecting SPIR-V with float16_t in it; Mesa's is a
different compiler. The version check stays for the proprietary driver, where it
was measured, and Turnip passes on its own account.
The on-screen keyboard raised its bar without raising a keyboard.
showSoftInput(SHOW_IMPLICIT) is a hint the system may decline, and it does for a
fullscreen immersive window like the game surface -- but visible was set either
way, so the extra-keys bar appeared over nothing. It now also drives the IME
through WindowInsetsControllerCompat, which is the supported route once
setDecorFitsSystemWindows(false) is in effect, and it already is. Both are used:
the old call still works on odd IMEs and asking twice costs nothing. hide()
mirrors it.
Space and Enter join the bar as wide keys. They are on the IME too, but the IME
is not reliably what comes up, and Space is the key that opens the debug menu
this was built for -- it should not depend on another keyboard appearing. Enter
was already there as a glyph and read as decoration; it says Enter now.
The emulated keyboard reaches games now, and the first thing it was used for was
a game's debug menu -- which opened on Space and then could not be navigated,
because a soft keyboard is built for typing text and has no arrows, no Escape and
no function row. For that job those are not optional extras, they are the whole
interaction.
A row of them floats above the IME whenever the keyboard is up: Esc, Tab, the
four arrows, Enter, and an Fn toggle for F1-F12. It scrolls sideways so nothing
is cut off on a narrow screen, and it appears and disappears with the keyboard,
so there is nothing to place in the touch layout and nothing to find.
This adds to the IME rather than replacing it. Prediction, swipe and non-Latin
input still come from whichever keyboard the user chose; only the keys that
keyboard cannot express come from here.
Taps go through SoftKeyboard.tap, the same paced queue the IME's own keys use, so
a press is held long enough for the guest to sample it. The keys use tap gesture
detection rather than clickable(): this sits beside a focused IME sink, and
anything focusable here can take focus off it and drop the keyboard mid-use.
The arrows are KEYCODE_DPAD_*, which the handler already maps to Qt's arrow
codes, so nothing was needed on the native side.
Four probes, all sampled or already on a timer, added while chasing the
Assassin's Creed loading hang. Each one existed because a fact that turned out to
be decisive was unreachable from outside.
sys_event: EVENTSPIN counts sends and receives and prints one line per million of
each. The syscall usage stats already said two calls dominated everything; they
could not say which port, which queue, or whether the receive blocked. It was one
thread posting a zero-data event to its own queue and taking it straight back,
2.2 million times a second -- a yield loop, not a deadlock, which is a different
thing to go looking for.
The SPU half of the stall dump gains res_now/res_moved and the first bytes of the
line an SPU is parked on. The wait loop wakes on either the counter moving or the
data changing, so a sleeping SPU proves the line is static rather than that a
notification was lost. Those are different bugs and the dump could not tell them
apart.
It also gains one kernel's registers and the local store around its pc, matching
what the PPU half has always printed. The SPU's decision to sleep is guest code;
the registers hold what it tested and the local store holds the test.
The PPU half gains the memory behind registers of a spinning thread. dump_all
prints eight bytes, enough to recognise a pointer and not enough to read the
struct behind it -- the field that settled this one was 0x74 bytes past a value
in r5.
One SPU and six pointers, deduplicated and capped: a dozen parked threads each
dragging a hex dump per register buries the report that explains the hang.
ldarx has a fast path: re-reserving the same 128-byte line the thread's last
successful stdcx wrote skips reloading ppu.rtime, on the theory that the hardware
caches the reservation across a chain of stores. The branch is empty, so rtime
keeps the value it had before that store -- and the store left the line's counter
128 higher. Every conditional store after the first one on a line therefore fails
its rtime != (res & -128) test by exactly 128, and keeps failing, because a guest
that retries re-enters the same fast path with the same stale value.
Assassin's Creed never gets past its loading screen because of it. libsre's
cellSpursAddUrgentCommand walks four urgent-command slots inside a single
reservation loop: it stores slot 0 back unchanged to release it, then can never
claim slot 1, and its failure path restarts the whole scan. Measured at 490
million failures on 0x102ed6b8, res-rtime == 128 on every one, data unchanged.
Downstream of that, everything else looked like the bug and was not. The job
chain is valid (workloadId 4), three of its four urgent slots stay empty, no
workload is ever marked ready, all six SPURS SPU kernels sleep correctly on a
control block nothing writes, and the main thread burns 2.2 million syscalls a
second in a yield loop waiting for a load that cannot finish. One missing
increment, five symptoms.
047f71b43 added this fast path for MGS4 along with a "rtime -= 128" here and a
"rtime += 128" in the store; the two cancel, and both were later dropped rather
than corrected, which left the fast path reading a stale value. Advancing rtime
at the store is what makes the empty branch correct: it is already current.
A raw override recorded in All Core Settings re-pushes at the tail of applyTo,
after the curated store has written the same node. So the recorded value wins
every time and the normal settings screen becomes decorative: it shows the
choice, saves the choice, and the choice is overwritten a moment later with
nothing on screen to say so. config.yml disagrees with the UI and there is no
way in the app to see why, or to undo it -- CoreSettingOverrides.clear() existed
and nothing called it.
That is not hypothetical. A test device carried
Core@@PPU Decoder = "Recompiler (LLVM)"
which silently defeated every attempt to boot a game on the interpreter,
including a run made specifically to find out whether a hang was a codegen bug.
The run happened, the setting was chosen, and the log recorded the recompiler.
All Core Settings now reads the store alongside the tree: it says how many paths
this scope remembers, marks each row that carries one, and offers Forget per row
and for the scope. Forgetting also restores the node -- the core's default first,
then a curated re-apply on top -- because dropping only the record would leave
the value it wrote still live, which looks like the button doing nothing.
Reset is two taps rather than an AlertDialog: dialogs swallow gamepad keys here,
and this screen opens from the in-game menu with only a controller in hand.
The migration clears the paths a curated screen also writes. Three others --
RSX Profiler, PPU Calling History, Disable SPU GETLLAR Spin Optimization -- have
no curated writer, so they are actively written back to their upstream default
rather than merely forgotten; forgetting alone would remove the record and keep
the effect. All three are instrumentation or debug levers that were never meant
to ship on.
Accurate ZCULL stats is deliberately left alone: no curated writer and no
debugging history, so a value there is most likely a deliberate per-game choice.
It is visible and clearable now, which is the point.
Two earlier migrations already purged diagnostics by name, and both had run on
the device that still had RSX Profiler recorded. Hence a screen rather than a
third list.
The keyboard setting, the on-screen keyboard hotkey, the touch button and the
IME plumbing all worked. Nothing behind them did, in three separate places:
- init_kb_handler installed NullKeyboardHandler unconditionally, so cellKb --
the API games actually read a keyboard through -- reported none attached no
matter what the UI said.
- NativeApp.usbKeyboardKey and usbSetKeyboardEnabled were Unsupported.note()
stubs. Every keystroke went into a no-op that returned false.
- The setting wrote [USB1] Type = hidkbd, which is PCSX2's emulated USB HID
keyboard. There is no such device in this core -- "hidkbd" appears nowhere
in it -- so that write only ever reached Unsupported.note("USB1/Type").
All three are inherited from the UI port, which is why the feature looked whole.
The desktop handler is a QObject that installs an event filter on a QWindow, so
none of it survives the port. It does not need to: everything that turns a key
into cellKb data already lives in KeyboardHandlerBase::HandleKey, and a concrete
handler owes it exactly one thing, a populated qt_code -> CELL_KEYC map.
virtual_keyboard_handler builds that map with the Qt key codes as literals, and
translates Android keycodes onto it -- including left/right modifiers, which have
to come back in the native_key encoding get_out_key_code compares against or
every modifier reads as the right-hand one.
The setting now writes Input/Output/Keyboard, which is what the core reads. That
happens once, in Emulator::Load, so it applies on the next boot rather than to a
game already running; the description says so now, because the old comment
claimed a live attach that never existed.
KeyEvent.getUnicodeChar() is carried through as well. cellKb derives its own
character from the raw code plus the live modifier state and does not need it,
but the emulator's own overlay text entry matches on the string.
__FILE__ expands to whatever path the compiler was handed, and RPCS3 prints source locations in
ensure() failures, fmt::throw_exception and assertions. Every one of those lines therefore carried
the full build directory into EVERY USER'S LOG -- on a developer machine that is a home directory,
and the shipped core contained 2500 copies of one username. It surfaced in a bug report where a
user's log showed somebody else's paths, which is a reasonable thing to be alarmed by.
-ffile-prefix-map rewrites the prefix at compile time, covering both __FILE__ and debug info, so
paths become relative-looking (./rpcs3/Emu/...) -- which is what a log wants to show anyway. No
runtime cost.
Applied before any add_subdirectory so third-party targets built in-tree are covered too: they
account for 32k of the roughly 52k embedded paths. Guarded with check_cxx_compiler_flag so a
toolchain without it still builds.
Two bugs, both mine, both in the new importer. Reported as "import failed, could not open
the zip".
The archive path could never succeed. These stage functions answer null to mean "no problem,
carry on", and importArchive folded the open into the same expression:
contentResolver.openInputStream(uri)?.use { stageArchive(...) }
?: Outcome(false, "Could not open the selected file")
so a null from stageArchive -- the SUCCESS return -- selected the elvis branch. Every archive
import reported a file it had in fact opened and read as unopenable, and returned before
discover() ever looked at what had been staged. The open is now checked on its own, so the
two cases cannot be confused again; the message was pointing at the wrong thing, which is
what sent the diagnosis into the zip handling.
Separately the file carried six NUL bytes where space character literals were meant:
trimEnd('\0'), it == '\0'. They compile -- '\0' is a valid Char -- so nothing complained, and
grep silently reports nothing for a file it decides is binary, which is why searching for
these came back empty on a file that plainly contained them.
Fixing them corrects the rule rather than restoring the intent, because the intent was wrong.
Spaces are ordinary in a downloaded folder name: "All Pro Football 2K8 roster/" is exactly
what a file manager produces. Stripping them silently renamed the user's folders, and the SAF
walk skipped any entry containing one, so a wrapper folder made its contents invisible. Source
names now reject only separators and control characters.
The destination name is no longer narrowed to a character set either. It comes from the game's
own SAVEDATA_DIRECTORY, and refusing one for holding an unanticipated character would produce
"no save data found" -- the same silent-looking failure this class exists to prevent. Only
separators, control characters and a leading dot are rejected, since those are what can
redirect a write or hide the result.
Android 11 stopped third-party file managers from writing into Android/data, so a user who
downloads a save cannot put it where the emulator reads from -- ZArchiver reports EACCES and
no file manager can do better. Reported against an All Pro Football 2K8 roster on an Ayn Thor
Pro. The platform rule is not ours to fix, but we are the only process that can still write
there and until now offered no way to ask us to, so there was no route in at all.
The destination folder name comes from the save's own PARAM.SFO rather than from what the
user's folder or archive is called. Games enumerate saves by matching dirNamePrefix against
the directory name, so a save under the wrong name produces no error the user ever sees --
the game just reports no save data and offers to start fresh, which reads as "the import did
nothing". The core writes SAVEDATA_DIRECTORY into every PARAM.SFO it saves and reads it back
to populate dirName, so the name that works travels inside the save; a renamed download still
lands correctly. The folder's own name is the fallback, and both go through the same
sanitiser because a value read out of a file is untrusted wherever it came from.
Staging follows TexturePackInstaller: everything is copied to a scratch directory beside the
destination, checked there, and only then renamed in, so a cancelled or failed import cannot
leave a half-written save and cannot destroy one the user already had. Archive entries are
rebuilt from sanitised components and any entry containing a '..' fails the whole archive --
this writes into app-private storage, which includes the native library directory, so a
zip-slip here is code execution rather than untidiness. Extracted sizes are counted while
writing rather than trusted from the entry header.
Two rows because the two pickers are different intents: an archive straight from a download,
or an already-unzipped folder. Both accept being pointed at either the save itself or a
parent holding several, since a user has no reason to know which they picked.
stageArchive/stageTree/commit are deliberately not savedata-specific -- the frame generation
plugin installer needs the same component (pick a file, verify it, atomically place it
somewhere the app owns) and should lift these rather than grow a second copy.
They are the one entry in that directory tracked in git rather than staged build output,
which is why .gitignore un-ignores them by name and verifyAngleLibs fails the build without
them.
0.9 shipped seven permanently-connected pads. Reported against LittleBigPlanet 2, which
reacts to the connected count and behaved as though 4+ controllers were plugged in at all
times.
Claiming all seven ports for the virtual handler is what lets a second controller work at
all -- that was the 0.9 fix and it stays -- but initVirtualPad called Init with
CELL_PAD_STATUS_CONNECTED unconditionally, and "this port exists" and "a controller is
plugged into this port" are not the same statement. cellPad derives now_connect by counting
ports whose status carries the CONNECTED bit, so every game asking how many pads were
attached was told seven.
Port 0 therefore starts CONNECTED and ports 1-6 start 0, with the bit set on a port the
first time real input arrives for it in _rpcsx_overlayPadData. No new event plumbing is
needed: pad_thread::update_pad_states already polls is_connected() against its cached
m_pads_connected -- value-initialised to false, so a port that starts disconnected fires
nothing at boot -- and calls pad_state_notify_state_change on a change, which is what
propagates m_port_status into cellPad's reported_info. Setting the bit is enough for the
existing path to publish it.
m_player_id is a const set at construction, not by Init, so reading it to pick the initial
status is safe at this point.
On a pad that reports L2/R2 as AXES rather than buttons they arrive in
dispatchGenericMotionEvent and never as a key, so the binder -- which lives in Compose's
onPreviewKeyEvent -- could not see them, and L2/R2 would not bind while every other button on
the same pad did. That depends on the controller MODEL, not the port, which is what makes it
present as a Player 2 problem: a second pad of a different make fails where the first worked.
Reported against Player 2 with everything else binding.
handleCaptureMotion already existed for exactly this shape -- the D-pad HAT arrives as an axis
on several handhelds and is synthesised into a key during capture -- so the triggers just join
its set and inherit its press/release tracking, which debounces the motion stream for
free.
Uses the same axis pairs as the gameplay path (sendTrigger), including the per-device third axis
some pads put the right trigger on, so a trigger that works in game can also be bound.
Threshold is a deliberate half-pull so resting drift on a worn trigger cannot self-bind.
The guest polls cellPad at its own rate -- 33ms at 30fps -- and a press plus its release are
two separate snapshot pushes with nothing between them. A press shorter than one poll interval
lands entirely between polls and the game never sees it. Steady presses always span a poll,
which is why a button works everywhere except during a rapid mash, and why a held button
(crouch) keeps working while everything tapped alongside it does not.
GestureLayer already knew this and worked around it locally with a 40ms hold in pulse();
ordinary touch taps and physical controller presses had no equivalent. Reported on Iron Man's
quick-time event, where circle must be pressed repeatedly and does not register, and again as
'only the crouch button works' with both on-screen controls and a PS5 pad.
Delaying a too-short release would NOT fix it and would look identical: in a mash, press N's
deferred release collides with press N+1 and the game sees one long press instead of several,
while a QTE counts presses. Each transition therefore gets its own slot -- press visible for
40ms, release visible for 40ms, then the next press -- so a mash arrives as distinct presses
rather than a hold.
A press with nothing queued ahead of it still goes through immediately, so normal input takes
no added latency; only the release of a tap shorter than 40ms is deferred, and only up to 40ms.
Queue depth is capped so a mash cannot accumulate while the guest is not consuming.
40ms matches the gesture path and clears one 60Hz sample. NEEDS FIGHTING-GAME TESTING: it also
paces the d-pad, and 40ms is about 2.4 frames at 60fps, so frame-tight directional input is the
case most likely to feel different.
Adding the TouchButtonId was not enough. The editor offers what the LAYOUT contains, not what
the enum declares, so the button existed and did nothing visible -- reported straight away.
Listed with enabled = false alongside the save/load/screenshot buttons, which is the same
opt-in shape. Existing layouts pick it up without being disturbed: TouchLayout.fromJson
splices in any default button a saved layout lacks, and defaultPortrait splices from this
same table, so one entry covers both orientations and everyone's current layouts.
Ports 2-7 were left as Null pad handlers unless a USB device happened to be plugged in. The
loop that claims them for the virtual handler existed, but only inside _rpcsx_usbDeviceEvent,
so it ran on a USB plug/unplug and nowhere else. A second controller on a phone is normally
BLUETOOTH, which never produces that event, so those ports stayed Null and a second pad did
not exist in the core at all. Per-player button mapping therefore looked correct -- the UI
stores those bindings regardless -- while the second controller did nothing in game. Reported
against Tekken 6. Now claimed at startup, next to player 1.
Also adds a KEYBOARD touch button (Kind.STATEACTION, so it emits no pad code and calls
MainActivityRuntime.toggleSoftKeyboard) for the same reason the hotkey exists: to reach the
keyboard without pausing. The hotkey needs a spare pad button, which a touch-only player does
not have. Opt-in, absent from the default layout, like the save/load/screenshot buttons.
Appending to TouchButtonId is safe: touch layouts serialise the id by NAME
(TouchButtonId.valueOf), unlike SysHotkey which is persisted by ordinal.
It existed only in the in-game pause menu, which made the On-Screen Keyboard hotkey's own
message a dead end: it tells you to turn this on in Network settings, and there was nothing
in Network settings to turn on. Reported from Discord after exactly that.
Same Settings.usbKeyboard field as the in-game row, so the two stay in sync, and indexed for
settings search.
Reverts 422d831ef and 00ce69a31.
ARMSX3 already had all of this. Settings.usbKeyboard writes USB1/Type = hidkbd and
NativeApp.usbSetKeyboardEnabled, the TOGGLE_KEYBOARD hotkey raises the Android IME through
SoftKeyboard.toggle, and dispatchKeyEvent already forwards keys via forwardKeyToUsbKeyboard.
The toast users see -- "Turn on Emulate USB Keyboard (Network settings) first" -- is that
feature correctly reporting that its setting is off, not a missing capability. What I added
was a second, parallel path through cellKb with its own setting and its own hotkey.
The revert is not only for redundancy. SysHotkey is persisted BY ORDINAL, as the comments
around TOGGLE_KEYBOARD and GYRO_RECENTER say in as many words, and both are appended last
for exactly that reason. KEYBOARD_TOGGLE was inserted mid-enum, ahead of GYRO_TOGGLE, which
re-points every binding after it for every existing user.
Uses the Android system IME rather than a drawn key grid, so layouts, languages, prediction
and emoji come for free and it is the keyboard users already know. Bound to a new
KEYBOARD_TOGGLE hotkey, so it can be raised and dismissed mid-game without opening
settings.
The IME only opens for a focused view that accepts input, so a zero-size transparent
EditText owns focus on demand. Its InputConnection does the real work, because an IME
reports typing in two different ways and only one of them is a key event:
sendKeyEvent backspace, enter, arrows -- forward the keycode as-is
commitText ordinary characters, with NO key event behind them
deleteSurroundingText some IMEs delete by range instead of sending backspace
commitText is synthesised with KeyCharacterMap.getEvents, which produces the shift presses
capitals and symbols need rather than guessing a keycode per character. Characters no
keycode can produce -- emoji, CJK picked from a candidate list -- are still delivered with
their unicode and KEYCODE_UNKNOWN, since the guest reads the unicode field and that is the
honest keycode for a character with no key behind it.
Also adds the Emulated Keyboard setting, without which all of this was inert: the core
defaults to keyboard_handler::null, so cellKb told games no keyboard was attached no matter
what was typed. Off by default, matching the core, because a game that sees a keyboard can
behave differently. The hotkey says so in its toast when the guest cannot receive keys,
rather than silently showing an IME that goes nowhere.
cellKb reported no keyboard at all, so games that need one were unreachable: NFS Most
Wanted's beta debug menu, and native keyboard support in games like Counter-Strike. The
only handler upstream ships, basic_keyboard_handler, derives from QObject and filters
QKeyEvent off a QWindow, and android/CMakeLists.txt excludes it with the rest of the Qt
input layer -- init_kb_handler was hardcoded to NullKeyboardHandler as a result.
Almost none of that handler is actually Qt-bound. KeyboardHandlerBase::HandleKey already
takes plain u32 codes and keyboard_consumer::ConsumeKey resolves them through
m_keys.find(code), so the code space only has to agree between whatever registers the
buttons and whatever injects them. android_keyboard_handler therefore registers ANDROID
KeyEvent keycodes directly rather than impersonating Qt. The PS3 side uses USB HID usage
IDs and Android's letters and digits are contiguous too, so those map arithmetically and
only the remainder needs a table. Android also distinguishes left from right modifiers,
which Qt cannot, so all eight are wired rather than four.
init_kb_handler now honours the Keyboard setting instead of always reporting none, and
_rpcsx_keyboardKey delivers one key through the usual dlsym bridge, returning false when
no keyboard is active so a caller can tell the difference.
A physical keyboard reaches the guest through dispatchKeyEvent. The test there is
KEYBOARD_TYPE_ALPHABETIC, not the event source: gamepads also report SOURCE_KEYBOARD for
their buttons, so filtering on source alone would send every controller press to the guest
keyboard as well as the pad. The event is consumed only when the native side reports the
key landed, which keeps a physical keyboard usable for UI navigation everywhere else.
Not yet done: the on-screen keyboard overlay, and a UI setting for the handler. The core
default is still keyboard_handler::null, so this is inert until Keyboard is set to Basic.
The ARM64 SPU gateway reserved a shared 8192-byte stack scratchpad. Compiled SPU
functions build no frames of their own on ARM64 -- GHC_frame_preservation_pass runs with
use_stack_frames = false -- so every one of them spills into that single reservation, and
a function needing more simply writes past it. Borderlands 2's 2401-instruction function
at LS 0x25da8 wants ~21 KB: the fault landed at sp+21760, exactly the top of the thread's
stack mapping, on the PROT_NONE guard page above it. x86 reserves 0xc8 in the same place
because LLVM emits ordinary per-function frames there, so this arrangement and this
failure are ARM64-only. Raised to 256 KB.
That is still a fixed bound rather than a scaling fix; a larger function could overflow
it the same way. use_stack_frames = true would scale, at a cost the pass comments call
out and which is not measured here.
Android threads also ran on an eighth of the stack they get elsewhere: the pthread path
passed null attributes, so bionic's 1 MB default applied where glibc gives 8 MB, measured
as a 0xfc000 stack mapping. Not the cause of this bug -- the overrun is off the TOP of the
stack, so size does not affect it, and 1 MB to 64 MB changed nothing -- but a real
discrepancy worth closing.
Both were invisible because of how the fault died. A guard page is not emulator memory,
so is_emulator_fault() correctly declines it, the handler forwards to libsigchain, and
ART's FaultManager reads the guest registers as an ArtMethod* and takes the process down.
No tombstone is produced, the async emulator log never reaches disk, and Android records
only 'SIGNALED status=11'.
Verified with the function compiled and no forced interpretation: zero stalls, zero
guard-page faults, 47 presented frames where the previous best was 18.
SHUFB: a7fc31f32 made two semantic changes to the ARM64 path, and BOTH have to go. It
widened the byteswap fold from splat-only constants to any constant, byte-reversing
non-splat ones in get_swap_from_const, and it added idx_selects_single, which treats a
mask whose bit 4 is known-constant across all lanes as single-source.
Borderlands 2's SPURS function at LS 0x25da8 is 1446 shufb whose data operand is usually
a non-splat constant -- 0xbf800000 built by ilhu/iohl, or a mask straight out of cbd/cwd.
Compiled, that function spins forever inside a single block: block_counter, loop count
and retreat count are byte-identical across six thread dumps spanning the hang, at 96%
CPU, so it never reaches a block boundary. Interpreted, the game boots.
Reverting the byteswap widening alone is NOT enough -- measured, and the hang came back
with seven stall dumps at 0x25da8. Disabling the whole ARM64 shufb block in favour of the
generic path also fixes it, which is what identifies the fold and the single-source
trigger rather than the tbl/tbx paths themselves. Kept narrow so ARM64 keeps its fast
paths.
CFLTS accurate xfloat: only the high side was guarded. The f32 path is a single saturating
fcvtzs.4s, but this one converts f64[4], and AArch64 has no v4f64->v4i32 form, so it
lowers to fcvtzs.2d twice plus uzp1 -- saturation happens at int64 range and uzp1 then
keeps the low 32 bits. Negative overflow therefore did not produce 0x80000000: -3e9 came
back as +1295786496.