If all inputs to an fmadds instruction (including cousins like fmsubs,
fnmadd...) are single-precision, then the result is identical between a
double-precision calculation with an error-free transform (whether the
calculation is fused or not) and a single-precision FMA instruction
(must be fused). So as a performance optimization in JitArm64, if we
were going to use double precision with EFT but the inputs are singles,
instead we'll use a normal single-precision FMA instruction without
anything extra. This lets us skip both the EFT and double-to-single
conversions.
Also renaming `inaccurate_fma` to `nonfused` because it's confusing that
`inaccurate_fma` and `m_accurate_fmadds` have such similar names
despite controlling separate things.
If result_reg is set to a temporary register instead of VD because of
accurate NaNs, there's no need to allocate a secondary temporary
register because of inaccurate FMA.
In the past, the register cache would contain either a host register or
an immediate (or neither) for a given guest register. Jit64::cmpXX would
roll with whichever one it got. But now that PR 12134 is merged, the
register cache can contain a host register at the same time as an
immediate. This gives us an optimization opportunity in Jit64::cmpXX.
Some paths are more efficient when we use an immediate and some paths
are more efficient when we don't, so to generate the best code, we
should carefully choose if we want an immediate or not rather than
leaving it to the register cache.
TextureCacheBase::LoadImpl has a hot path where the passed-in
TextureInfo never gets used. Instead of passing in a TextureInfo, let's
pass in the stage and create the TextureInfo from the stage if needed.
This unlocks somewhere above an additional 4% performance boost in the
Hoth level of Rogue Squadron 2 on my PC. Performance varies, making it
difficult for me to measure, so treat this as a very approximate number.
When we're emulating single-precision FMA using an FMA instruction,
there's no precision benefit from using a double-precision instruction,
assuming all inputs are single-precision. But when we're emulating
single-precision FMA using separate multiplication and addition
instructions, there is.
This change increases the precision of inaccurate FMA to the same level
as Jit64, which matters since the only reason we have the inaccurate
FMA mode is for sync compatibility with Jit64.
The check only happened if `USE_VTUNE` wasn't defined, and in that case
it was immediately followed by the same check again.
The check used to avoid an unnecessary call to `StringFromFormatV` in
certain circumstances, but that call was removed in
be81fe86e1.
The patches rearrange some branching to insert a call to VIWaitForRetrace in the main game loop.
This allows ImmediateXFB to work properly so it is no longer forced off by the game ini.
Building on macOS with a recent CMake version would result in the
following error:
CMake Error at Source/Core/MacUpdater/CMakeLists.txt:48 (add_custom_command):
The following keywords are not supported when using
add_custom_command(TARGET): DEPENDS
As it turns out, this form of `add_custom_command` does not accept
DEPENDS, but versions of CMake prior to 3.31 silently dropped it.
The TextureInfo constructor creates a vector of MipLevels. This could be
good for performance if MipLevels are accessed very often for each
TextureInfo, but that's not the case. Dolphin creates thousands of
TextureInfos per second that it never accesses the mipmap levels of
because there's a hit in the texture cache, and in the uncommon case of
a texture cache miss, the mipmap levels only get looped through once.
To make the common case of texture cache hits as fast as possible, let's
not create a vector in the TextureInfo constructor. This commit
implements a custom iterator for MipLevels instead.
In my testing on the Death Star level of Rogue Squadron 2, this speeds
up TextureInfo::FromStage by 200%, giving an overall emulation speedup
of a bit over 1%. Results on the Hoth level are even better, with
TextureInfo::FromStage being close to 300% faster and overall emulation
being over 4% faster. (Single core, no GPU texture decoding.)