It is my opinion that nobody should use NKit disc images without
being aware of the drawbacks of them. Since it seems like almost
nobody who is using NKit disc images knows what NKit is (hmm, now
how could that have happened...?), I am adding a warning to Dolphin
so that you can't run NKit disc images without finding out about the
drawbacks. In case someone really does want to use NKit disc images,
the warning has a "Don't show this again" option. Unfortunately, I
can't retroactively add the warning where it's most needed:
in Dolphin 5.0, which does not support Wii NKit disc images.
Pretty much the same optimization we did for AVX, although slightly more
constrained because we're stuck with the two-operand instruction where
destination and source have to match.
We could also specialize the case where registers b, c, and d are all
distinct, but I decided against it since I couldn't find any game that
does this.
Before:
66 0F 57 C0 xorpd xmm0,xmm0
66 41 0F C2 C1 06 cmpnlepd xmm0,xmm9
41 0F 28 CE movaps xmm1,xmm14
66 41 0F 38 15 CC blendvpd xmm1,xmm12,xmm0
44 0F 28 F1 movaps xmm14,xmm1
After:
66 0F 57 C0 xorpd xmm0,xmm0
66 41 0F C2 C1 06 cmpnlepd xmm0,xmm9
66 45 0F 38 15 F4 blendvpd xmm14,xmm12,xmm0
AVX has a four-operand VBLENDVPD instruction, which allows for the first
input and the destination to be different. By taking advantage of this,
we no longer need to copy one of the inputs around and we can just
reference it directly, provided it's already in a register (I have yet
to see this not be the case).
Before:
66 0F 57 C0 xorpd xmm0,xmm0
F2 41 0F C2 C6 06 cmpnlesd xmm0,xmm14
41 0F 28 CE movaps xmm1,xmm14
66 41 0F 38 15 CA blendvpd xmm1,xmm10,xmm0
F2 44 0F 10 F1 movsd xmm14,xmm1
After:
66 0F 57 C0 xorpd xmm0,xmm0
F2 41 0F C2 C6 06 cmpnlesd xmm0,xmm14
C4 C3 09 4B CA 00 vblendvpd xmm1,xmm14,xmm10,xmm0
F2 44 0F 10 F1 movsd xmm14,xmm1
Fixes a critical regression where 95945a0 made us unable to
start emulation on Android 10 and newer. Android is restricting
direct access to /dev/ashmem starting with the new SDK version,
but we can use the new (and simpler) ASharedMemory API instead.
We have to keep using the /dev/ashmem approach on old versions
of Android, though.
This modifies GCMemcard::TitlePresent() to match my findings of how the GC BIOS and various games behave when you alter the fields in the directory entry.
It looks like for a save to be recognized by a game, the following have to be true:
- Game code and maker code must exactly match what the game expects.
- Filename is only checked up to the first null byte. All bytes afterwards can be whatever.
The BIOS itself does a full compare of the filename when checking for whether it should allow copying a file from one card to another, but behaves oddly in some cases when there's non-null bytes after the first null. See the big comment in `HasSameIdentity()` for details.
