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.
Happens in Super Mario Sunshine. You could probably do something similar
for b == -1 (like we do for subfic), but I couldn't find any titles that
do this.
- Case 1: d == a
Before:
41 8B C7 mov eax,r15d
41 BF 00 00 00 00 mov r15d,0
44 2B F8 sub r15d,eax
After:
41 F7 DF neg r15d
- Case 2: d != a
Before:
BF 00 00 00 00 mov edi,0
41 2B FD sub edi,r13d
After:
41 8B FD mov edi,r13d
F7 DF neg edi
Consider the case where d and a refer to the same PowerPC register,
which is known to hold an immediate value by the RegCache. We place a
ReadWrite constraint on this register and bind it to an x86 register.
The RegCache then allocates a new register, initializes it with the
immediate, and returns a RCX64Reg for both d and a.
At this point information about the immediate value becomes unreachable.
In the case of subfx, this generates suboptimal code:
Before 1:
BF 1E 00 00 00 mov edi,1Eh <- done by RegCache
8B C7 mov eax,edi
8B FE mov edi,esi
2B F8 sub edi,eax
Before 2:
BE 00 AC 3F 80 mov esi,803FAC00h <- done by RegCache
8B C6 mov eax,esi
8B 75 EC mov esi,dword ptr [rbp-14h]
2B F0 sub esi,eax
The solution is to explicitly handle the constant a case before having
the RegCache allocate registers for us.
After 1:
8D 7E E2 lea edi,[rsi-1Eh]
After 2:
8B 75 EC mov esi,dword ptr [rbp-14h]
81 EE 00 AC 3F 80 sub esi,803FAC00h
-If adding 2 devices with the same name, they their unique id wouldn't be increased, causing a conflict.
-Removing a device wouldn't actually remove it from the internal devices list because the list of devices had already been updated when going through it.
-It was possible to remove devices belonging to other sources by adding a device with the same name and then removing it.
The name was confusing as changing it at runtime would not change the window to fullscreen, as it effectively only affects the start of the emulation.
Also blocked the ability to change it when the emulation is running, to be more inline with other similar settings, like "Render to main Window".
Also provides operator!= for logical symmetry.
We can also take the arguments by value, as the arguments are trivially
copyable enum values which fit nicely into registers already.
https://bugs.dolphin-emu.org/issues/6749
This change fixes the scratchy audio in Teenage Mutant Ninja Turtles (SX7E52/SX7P52). The game starts an audio interface DMA with an unaligned address, and because Dolphin was not masking off the low 5 bits of AUDIO_DMA_START_LO, all future AI DMAs were misaligned. To understand why, it is instructive to refer to AUDIO_InitDMA() in libogc, which behaves the same as the official SDK:
_dspReg[25] = (_dspReg[25]&~0xffe0)|(startaddr&0xffff);
The implementation does not mask off the low bits of the passed in value before it ORs them with low bits of the current register value. Therefore, if they are not masked off by the hardware itself, they become permanently stuck once set.
Adding a write mask for AUDIO_DMA_START_LO is enough to fix the bug in TMNT, but I decided to run some tests on GC and Wii to find the correct write masks for the surrounding registers, as only a couple were already being masked. Dolphin has gotten away with not masking the rest because many are already A) masked on read (or never read) by the SDK and/or B) masked on use (or never used) in Dolphin.
This leaves just three registers where the difference may be observable: AR_DMA_CNT_H and AUDIO_DMA_START_HI/LO.
operator[] performs a default construction if an object at the given key
doesn't exist before overwriting it with the one we provide in operator=
insert_or_assign performs optimal insertion by avoiding the default
construction if an entry doesn't exist.
Not a game changer, but it is essentially a "free" change.
Allows lookups to be done with std::string_view or any other string
type. This allows for non-allocating strings to be used with the name
lookup without needing to construct a std::string.
Cleans up some locks that explicitly specify the recursive mutex type in
it. Meant to be included with the previous commit that cleaned out
regular mutexes, but I forgot.
This code was storing references to patch entries which could move around in memory if a patch was erased from the middle of a vector or if the vector itself was reallocated. Instead, NewPatchDialog maintains a separate copy of the patch entries which are committed back to the patch if the user accepts the changes.
These games are erroneously zeroing buffers before they can be fully copied to ARAM by DMA. The responsible memset() calls are followed by a call to DVDRead() which issues dcbi instructions that effectively cancel the memset() on real hardware. Because Dolphin lacks dcache emulation, the effects of the memset() calls are observed, which causes missing audio.
In a comment on the original bug, phire noted that the issue can be corrected by simply nop'ing out the offending memset() calls. Because the games dynamically load different .rel executables based on the character and/or language, the addresses of these calls can vary.
To deal generally with the problem of code being dynamically loaded to fixed, known addresses, the patch engine is extended to support conditional patches which require a match against a known value. This sort of thing is already achievable with Action Replay/Gecko codes, but their use depends on enabling cheats globally in Dolphin, which is not a prerequisite shared by patches.
Patches are included for every region, character, and language combination. They are enabled by default.
The end result is an approximation of the games' behavior on real hardware without the associated complexity of proper dcache emulation.
https://bugs.dolphin-emu.org/issues/9840
The config version should always be incremented whenever config is
changed, regardless of callbacks being suppressed or not.
Otherwise, getters can return stale data until another config change
(with callbacks enabled) happens.
C++17 allows omitting the mutex type, which makes for both less reading
and more flexibility (e.g. The mutex type can change and all occurrences
don't need to be updated).
Allows the analyzer to exist independently of the DSP structure. This
allows for unit-tests to be created in a nicer manner.
SDSP is only necessary during the analysis phase, so we only need to
keep a reference around to it then as opposed to the entire lifecycle of
the analyzer.
This also allows the copy/move assignment operators to be defaulted, as
a reference member variable prevents that.
Now that we have the convenience functions around the flag
bit manipulations, there's no external usages of the flags, so we can
make these private to the analyzer implementation.
Now the Analyzer namespace is largely unnecessary and can be merged with
the DSP namespace in the next commit.
This commit implements the following commands:
* open
* close
* GetMode
* SetLinkState (used to actually trigger scanning)
* GetLinkState (used to check if the driver is in the expected state)
* GetInfo
* RecvFrame and RecvNotification (stubbed)
* Disassociate (stubbed)
GetInfo was already implemented, but the structure wasn't initialized
correctly so the info was being rejected by official titles.
That has also been fixed in this commit.
Some of the checks may seem unimportant but official titles actually
require WD to return error codes... Failing to do so can cause hangs
and softlocks when DS communications are shut down.
This minimal implementation is enough to satisfy the Mii channel
and all other DS games, except Tales of Graces (https://dolp.in/i11977)
which still softlocks because it probably requires us to actually
feed it frame data.
NCD returns an error if it receives a request to lock the driver
when it is already locked.
Emulating this may seem pointless, but it turns out PPC-side code
expects NCD to return an error and will immediately fail and stop
initialising wireless stuff if NCD succeeds.
In 8c723d0, I intended to update the main activity, emulation
activity and game properties dialog, but I forgot to actually
update the game properties dialog. This commit fixes that.
The changes outside of GamePropertiesDialog.java are just
to hide the Wii controller settings for GameCube games.
Localizes code that modifies m_dsp into the struct itself. This reduces
the overal coupling between DSPCore and SDSP by reducing access to its
member variables.
This commit is only code movement and has no functional changes.
An unfortunately large single commit that deglobalizes the DSP code.
(which I'm very sorry about).
This would have otherwise been extremely difficult to separate due to
extensive use of the globals in very coupling ways that would result in
more scaffolding to work around than is worth it.
Aside from the video code, I believe only the DSP code is the hairiest
to deal with in terms of globals, so I guess it's best to get this dealt
with right off the bat.
A summary of what this commit does:
- Turns the DSPInterpreter into its own class
This is the most involved portion of this change.
The bulk of the changes are turning non-member functions into member
functions that would be situated into the Interpreter class.
- Eliminates all usages to globals within DSPCore.
This generally involves turning a lot of non-member functions into
member functions that are either situated within SDSP or DSPCore.
- Discards DSPDebugInterface (it wasn't hooked up to anything,
and for the sake of eliminating global state, I'd rather get rid of
it than think up ways for this class to be integrated with
everything else.
- Readjusts the DSP JIT to handle calling out to member functions.
In most cases, this just means wrapping respective member function
calles into thunk functions.
Surprisingly, this doesn't even make use of the introduced System class.
It was possible all along to do this without it. We can house everything
within the DSPLLE class, which is quite nice =)
Shifting zero by any amount always gives zero.
Before:
41 B9 00 00 00 00 mov r9d,0
41 8B CF mov ecx,r15d
49 C1 E1 20 shl r9,20h
49 D3 F9 sar r9,cl
49 C1 E9 20 shr r9,20h
After:
Nothing, register is set to constant zero.
Before:
41 B8 00 00 00 00 mov r8d,0
41 8B CF mov ecx,r15d
49 C1 E0 20 shl r8,20h
49 D3 F8 sar r8,cl
41 8B C0 mov eax,r8d
49 C1 E8 20 shr r8,20h
44 85 C0 test eax,r8d
0F 95 45 58 setne byte ptr [rbp+58h]
After:
C6 45 58 00 mov byte ptr [rbp+58h],0
Occurs a bunch of times in Super Mario Sunshine. Since this is an
arithmetic shift a similar optimization can be done for constant -1
(0xFFFFFFFF), but I couldn't find any game where this happens.
Shifting zero by any amount always gives zero.
Before:
41 BF 00 00 00 00 mov r15d,0
8B CF mov ecx,edi
49 D3 E7 shl r15,cl
45 8B FF mov r15d,r15d
After:
Nothing, register is set to constant zero.
All games I've tried hit this optimization on launch. In Soul Calibur II
it occurs very frequently during gameplay.
Much like we did for srawx. This was already implemented on JitArm64.
Before:
B8 00 00 00 00 mov eax,0
8B F0 mov esi,eax
C1 E8 1F shr eax,1Fh
23 C6 and eax,esi
D1 FE sar esi,1
88 45 58 mov byte ptr [rbp+58h],al
After:
C6 45 58 00 mov byte ptr [rbp+58h],0
If both input registers hold known values at compile time, we can just
calculate the result on the spot.
Code has mostly been copied from JitArm64 where it had already been implemented.
Before:
BF FF FF FF FF mov edi,0FFFFFFFFh
8B C7 mov eax,edi
C1 FF 10 sar edi,10h
C1 E0 10 shl eax,10h
85 F8 test eax,edi
0F 95 45 58 setne byte ptr [rbp+58h]
After:
C6 45 58 01 mov byte ptr [rbp+58h],1
More efficient code can be generated if the shift amount is known at
compile time. We can once again take advantage of shifts with the shift
amount in an 8-bit immediate to eliminate ECX as a scratch register,
reducing register pressure and removing the occasional spill. We can
also do 32-bit shifts instead of 64-bit operations.
We recognize four distinct cases:
- The special case where we're dealing with the PowerPC's quirky shift
amount masking. If the shift amount is a number from 32 to 63, all
bits are shifted out and the result it either all zeroes or all ones.
Before:
B9 F0 FF FF FF mov ecx,0FFFFFFF0h
8B F7 mov esi,edi
48 C1 E6 20 shl rsi,20h
48 D3 FE sar rsi,cl
8B C6 mov eax,esi
48 C1 EE 20 shr rsi,20h
85 F0 test eax,esi
0F 95 45 58 setne byte ptr [rbp+58h]
After:
8B F7 mov esi,edi
C1 FE 1F sar esi,1Fh
0F 95 45 58 setne byte ptr [rbp+58h]
- The shift amount is zero. Not calculation needs to be done, just clear
the carry flag.
Before:
B9 00 00 00 00 mov ecx,0
49 C1 E5 20 shl r13,20h
49 D3 FD sar r13,cl
41 8B C5 mov eax,r13d
49 C1 ED 20 shr r13,20h
44 85 E8 test eax,r13d
0F 95 45 58 setne byte ptr [rbp+58h]
After:
C6 45 58 00 mov byte ptr [rbp+58h],0
- The carry flag doesn't need to be computed. Just do the arithmetic
shift.
Before:
B9 02 00 00 00 mov ecx,2
48 C1 E7 20 shl rdi,20h
48 D3 FF sar rdi,cl
48 C1 EF 20 shr rdi,20h
After:
C1 FF 02 sar edi,2
- The carry flag must be computed. In addition to the arithmetic shift,
we do a shift to the left and and them together to know if any ones
were shifted out. It's still better than before, because we can do
32-bit shifts.
Before:
B9 02 00 00 00 mov ecx,2
49 C1 E5 20 shl r13,20h
49 D3 FD sar r13,cl
41 8B C5 mov eax,r13d
49 C1 ED 20 shr r13,20h
44 85 E8 test eax,r13d
0F 95 45 58 setne byte ptr [rbp+58h]
After:
41 8B C5 mov eax,r13d
41 C1 FD 02 sar r13d,2
C1 E0 1E shl eax,1Eh
44 85 E8 test eax,r13d
0F 95 45 58 setne byte ptr [rbp+58h]
More efficient code can be generated if the shift amount is known at
compile time. Similar optimizations were present in JitArm64 already,
but were missing in Jit64.
- By using an 8-bit immediate we can eliminate the need for ECX as a
scratch register, thereby reducing register pressure and occasionally
eliminating a spill.
Before:
B9 18 00 00 00 mov ecx,18h
41 8B F7 mov esi,r15d
48 D3 E6 shl rsi,cl
8B F6 mov esi,esi
After:
41 8B CF mov ecx,r15d
C1 E1 18 shl ecx,18h
- PowerPC has strange shift amount masking behavior which is emulated
using 64-bit shifts, even though we only care about a 32-bit result.
If the shift amount is known, we can handle this special case
separately, and use 32-bit shift instructions otherwise. We also no
longer need to clear the upper 32 bits of the register.
Before:
BE F8 FF FF FF mov esi,0FFFFFFF8h
8B CE mov ecx,esi
41 8B F4 mov esi,r12d
48 D3 E6 shl rsi,cl
8B F6 mov esi,esi
After:
Nothing, register is set to constant zero.
- A shift by zero becomes a simple MOV.
Before:
BE 00 00 00 00 mov esi,0
8B CE mov ecx,esi
41 8B F3 mov esi,r11d
48 D3 E6 shl rsi,cl
8B F6 mov esi,esi
After:
41 8B FB mov edi,r11d
Pokechu22