If the register pressure is high when allocating registers,
Arm64FPRCache may spill a guest register which we are going to
allocate later during the current instruction, which has the
side effect of turning it into double precision. This will have
bad consequences if we are assuming that it is single precision,
so let's add some asserts to detect if that ever happens.
PR #2663 added a Jit64 implementation of dcbX and a fast path to skip JIT cache invalidation. Unfortunately, there is a mismatch between address spaces in this optimization. It tests the effective address (with the top 3 bits cleared) against the valid block bitset which is intended to be indexed by physical address. While this works in the common case, it fails (for example) when the effective address is in the 7E... region (a.k.a. "fake VMEM"). This may also fall apart under more complex memory mapping scenarios requiring full MMU emulation.
The good news is that even without this fast path, the underlying call to JitInterface::InvalidateICache() still does very little work in the common case. It correctly translates the effective address to a physical address which it tests against the valid block bitset, skipping invalidation if it is not necessary. As such, the cost of removing the fast path should not be too high.
The Jit64 implementation is retained, though all it does now is emit a call. This is marginally more efficient than simple interpreter fallback, which involves an extra call. The JitArm64 implementation has also been fixed.
The game Happy Feet is fixed by this change, as it loads code in the 7E... address region and depends upon JIT cache invalidation in reponse to dcbf.
https://bugs.dolphin-emu.org/issues/12133
At least on some CPUs (I found out about this from the
Arm Cortex-A76 Software Optimization Guide), using X30
with BLR is one cycle slower than using another register.
Previously, eaddr would only be partially initialized in the ipv6 case.
Even if there's no support for it, we may as well ensure that the
variable always has deterministic initialization.
While we're at it, we can make the parameter a const reference, given no
members are modified.
EmulationActivity has an instance of Settings. If you go to
SettingsActivity from EmulationActivity and change some settings,
the changes get saved to disk, but EmulationActivity's Settings
instance still contains the old settings in its map of all
settings (assuming the EmulationActivity was not killed by the
system to save memory). Then, once you're done playing your
game and exit EmulationActivity, EmulationActivity calls
Settings.saveSettings. This call to saveSettings first overwrites
the entire INI file with its map of all settings (which is
outdated) in order to save any legacy settings that have changed
(which they haven't, since the GUI doesn't let you change legacy
settings while a game is running). Then, it asks the new config
system to write the most up-to-date values available for non-legacy
settings, which should make all the settings be up-to-date again.
The problem here is that the new config system would skip writing
to disk if no settings changes had been made since the last time
we asked it to write to disk (i.e. since SettingsActivity exited).
NB: Calling Settings.loadSettings in EmulationActivity.onResume
is not a working solution. I assume this is because
SettingsActivity saves its settings in onStop and not onPause.
For certain occurrences of nandx/norx, we declare a ReadWrite constraint
on the destination register, even though the value of the destination
register is irrelevant. This false dependency would force the RegCache
to generate a redundant MOV when the destination register wasn't already
assigned to a host register.
Example 1:
BF 00 00 00 00 mov edi,0
8B FE mov edi,esi
F7 D7 not edi
Example 2:
8B 7D 80 mov edi,dword ptr [rbp-80h]
8B FE mov edi,esi
F7 D7 not edi
Also avoid files without a name before the extension (name: ".ini")
from being added to the list because then they wouldn't be saveable
and it would appear with an empty name anyway.
This function has been marked as obsolete. In Qt 6.0 it's removed
entirely, so we must use getContentsMargin() explicitly instead
(margin() would do this for us).
Ditto for setMargin(), in which case we use setContentsMargin instead.
setMargin() would just pass its argument to all four parameters of
setContentsMargin(), so we can do the same.
This literal was deprecated in 5.14.0. Not to mention it wasn't
documented as part of the API either: see the 5.14.0 changelog here:
https://code.qt.io/cgit/qt/qtbase.git/tree/dist/changes-5.14.0?h=v5.14.0
On Qt 6.0 this define is removed entirely. To stay forward compatible,
we can make use of QStringLiteral instead.
When a game is selected, the option to add a shortcut of the game to the desktop is given. Uses native Windows API since Qt lacks support for adding shortcuts.
FinalizeCarryOverflow didn't maintain XER[OV/SO] properly due to an
oversight. Here's the code it would generate:
0: 9c pushf
1: 80 65 3b fe and BYTE PTR [rbp+0x3b],0xfe
5: 71 04 jno b <jno>
7: c6 45 3b 03 mov BYTE PTR [rbp+0x3b],0x3
000000000000000b <jno>:
b: 9d popf
At first glance it seems reasonable. The host flags are carefully
preserved with PUSHF. The AND instruction clears XER[OV]. Next, an
conditional branch checks the host's overflow flag and, if needed, skips
over a MOV that sets XER[OV/SO]. Finally, host flags are restored with
POPF.
However, the AND instruction also clears the host's overflow flag. As a
result, the branch that follows it is always taken and the MOV is always
skipped. The end result is that XER[OV] is always cleared while XER[SO]
is left unchanged.
Putting POPF immediately after the AND would fix this, but we already
have GenerateOverflow doing it correctly (and without the PUSHF/POPF
shenanigans too). So let's just use that instead.
