Previously, given cases such as 0x80000000 / 0xFFFFFFFF we'd incorrectly
set the destination register value to zero. If the dividend is negative,
then the destination should be set to -1 (0xFFFFFFFF), however if the
dividend is positive, then the destination should be set to 0.
Note that the 750CL documents state that:
"If an attempt is made to perform either of the divisions --
0x80000000 / -1 or <anything> / 0, then the contents of rD are
undefined, as are the contents of the LT, GT, and EQ bits of the CR0
field (if Rc = 1). In this case, if OE = 1 then OV is set."
So this is a particular behavior of the hardware itself.
Executing a supervisor-level instruction in user mode is supposed to
cause a program exception to occur.
The following supervisor instructions are present:
- dcbi
- mfmsr
- mfspr
- mfsr
- mfsrin
- mtmsr
- mtspr
- mtsr
- mtsrin
- rfi
- tlbie
- tlbsync
In 0337ca116a checks within mfspr and
mtspr were added. This change adds the trivial checks to the other
instructions.
Keeps signed values out of bit arithmetic (not that there's any issues
that could arise from it in these situations, but it does look more
consistent, and silences compiler warnings)
Also ensure that all members of the class are initialized on
construction as well. Previously the bool indicating if options are
dirty wouldn't be initialized, which could be read uninitialized if an
instance was constructed and then IsDirty() is called.
Keeps all of the interpreter-specific exception handling functions
together in a reusable way across translation units, similar to
FPUtils.h for reusable floating-point functions.
Given this is a base class, we should clearly state what the parameters
to the functions in its exposed interface actually mean or represent.
This avoids needing to hunt for the definition of the functions in cpp
files.
While we're at it, normalize said parameter names so they follow our
naming guidelines.
There's no reason to use int here as opposed to an unsigned value.
Video_AccessEFB() takes its arguments as u32 values, so we'd be doing
sign conversions for no reason here (along with causing avoidable
compiler warnings).
If a program executing in user mode tries to write to any SPRs other than
XER, LR, or CTR registers, then a program exception occurs. Similarly
this also applies for reading SPRs as well, however the upper and lower
timebase halves can also be read (but not written to).
If HID0.NOOPTI is set, then dcbt and dcbtst are no-oped globally. We
currently don't perform data cache emulation, but we put this in anyway
so this detail isn't forgotten about if data cache emulation is
introduced at some point in the future.
This function in both JITs is only ever called by passing the JIT's code
buffer into it. Given this is already accessible, since the functions
are part of the respective JIT class, we can just remove this parameter.
This also cleans up accesses with the new code buffer, as we don't need
to do janky looking dereference-then-index expressions.
This class effectively acted as a "discount vector", that would simply
allocate memory and then delete it in the destructor when it goes out of
scope.
We can just use a std::vector directly to reduce this boilerplate.
Given this is a bitmask, we should be using an unsigned type to store it
(especially given it's outside the range an int can represent properly
without being considered negative).
No behavior change is caused by this, it just silences a sign conversion
warning.
PowerPC.h at this point is pretty much a general glob of stuff, and it's
unfortunate, since it means pulling in a lot of unrelated header
dependencies and a bunch of other things that don't need to be seen by
things that just want to read memory.
Breaking this out into its own header keeps all the MMU-related stuff
together and also limits the amount of header dependencies being
included (the primary motivation for this being the former reason).
Github didn't detect conflicts here, however, since the float handling
functions were moved into the Common namespace, this would cause a build
failure.
Ideally none of these macros would exist (long-term goal), however in
the meantime at least make sure expressions always evaluate correctly
(thankfully no current usages rely on this).
Given we're operating with flags and bit representations, lets avoid
signed values here. It lessens the amount of sign conversion warnings
and lessens the amount of things to think about screwing you over when
making changes to the interpreter among other things.
These can be expressed in a slightly cleaner manner without so many
casts. While we're at it, also get rid of unnecessary indexing (we
already have the result nearby).
Extracts the self-contained code into its own function to clean up the
flow of Jit() a little more.
This also introduces a helper function to HLE.h that will be used to
reduce the boilerplate here and in the interpreter and Jit64 in the
following commits.
This function performs all of the preliminary checks required prior to
attempting to hook/replace a function at a given address. The function then
calls a provided object that satisfies the FunctionObject concept in the
C++ standard library. This can be a lambda, a regular function pointer,
an object with an overloaded function call operator, etc. The only
requirement is that the function return a bool, indicating whether or
not the function was replaced, and that it can take parameters in the
form: fn(u32 function, HLE::HookType type)
Gets rid of a second pair of ifdefs in the constructor. This also makes
sure the fd on Unix/BSD platforms is uniformly initialized. Previously
fd would be in an inconsistent state on FreeBSD or OpenBSD due to the
BSD OS checks not being present in the #elif within the constructor.
Previously, the entirety of CEXIETHERNET was exposed publically, which
wasn't necessary. We simply make the thread function part of the
internal interface, which gives it access to internal data members,
while keeping everything else outside of it.
Given these HLE classes inherit from a common base with a virtual
destructor, override is more appropriate here, as virtual propagates to
these destructors anyway.
This is also safer. If the base class' destructor is ever made
non-virtual, then these classes will cause a compilation error if they
aren't taken into account, as they'd be overriding a non-virtual
function (the destructor).
Moves the codebuffer access variables closer to their first use, and
gets rid of multiple indexing expressions. We already know which op
we're accessing in particular, so just make a reference to it and access
it instead of duplicating the expression all over the place.
A call like ReplaceAddress(address, 0) is pretty ambiguous; so is
ReplaceAddress(address, false), so use an enum class that tells people
straight-up what the replacer is.
This also gets rid of the really weird naming, where if 'blr' is true,
we'd be replacing the address with a NOP, rather than an actual BLR
instruction, so we invert that so it actually makes sense. There's no
actual bug fixed here though, considering the OnInsert functions
specified the correct values; it's literally just weird naming.
Without this macro, if any signals or slots were attempted to be used,
they wouldn't work; neither would various other features of the Qt
meta-object system. This can also lead to weird behavior in other
circumstances. Qt's documentation specifically states:
"Therefore, we strongly recommend that all subclasses of QObject use the
Q_OBJECT macro regardless of whether or not they actually use signals,
slots, and properties."
on its page for "The Meta-Object System", which can be seen here:
https://doc.qt.io/qt-5/metaobjects.html
Let's opt for "always do the right thing", and keep the code extensible
for the future and not have random things blow up on us.
Makes the enum strongly typed. A function for retrieving the string
representation of the enum is also added, which allows hiding the array
that contains all of the strings from view (i.e. we operate on the API,
not the exposed internals). This also allows us to bounds check any
querying for the strings.
This allows avoiding two copies of the executable data being created in
the following scenario (using pseudocode):
some_function()
{
std::vector<u8> data = ...;
DolReader reader{data};
...
}
In this scenario, if we only use the data for passing it to DolReader,
then we have to perform a copy, as the constructor takes the std::vector
as a constant reference -- you cannot move from a constant reference,
and so we copy data into the DolReader, and perform another copy in the
constructor itself when assigning the data to the m_bytes member
variable. However, we can do better.
Now, the following is allowable as well:
some_function()
{
std::vector<u8> data = ...;
DolReader reader{std::move(data)};
...
}
and now we perform no copy at any point in the reader's construction, as
we just std::move the data all the way through to m_bytes.
In the case where we *do* want to keep the executable data around after
constructing the reader, then we can just pass the vector without
std::move-ing it, and we only perform a copy once (as we'll std::move
said copy into m_bytes). Therefore, we get a more flexible interface
resource-wise out of it.
GetHandle() should really not even be part of IOFile's interface, but
since it is (for the time being), we can cull unnecessary usages of it.
In this case, the WriteBytes() function does what we need without using
the underlying handle directly.
This allows getting rid of casts. We can also leverage std::min to allow
making relevant variables const. Also make the "empty" table const to
allow it to be read-only.
Converts them from 0 == success, 1 == failure to using the built-in
standard bool. Also while we're at it, const qualify write_sector's
"sector" parameter, since nothing in the function modifies the data
being pointed to.
Avoids needing to iterate and append the characters in one case. This also
alters the function to not need to construct a temporary std::string
(QString's toUtf8() is sufficient, as QByteArray exposes iterators).
toStdString() is equivalent to retrieving the QString's underlying
QByteArray via calling QString's .toUtf8 member function and then
calling .toStdString() on the result of it (discarding the QByteArray
afterwords), so this just trims off an unnecessary step in the process.
This is also somewhat more indicative of the conversions going on:
toStdString() converts the underlying character sequence of a
QString to UTF-8, not strict ASCII, so we're really using a superset of
ASCII.
Also move it to MathUtils where it belongs with the rest of the
power-of-two functions. This gets rid of pollution of the current scope
of any translation unit with b<value> macros that aren't intended to be
used directly.
Given bit conversions between types are quite common in emulation
(particularly when it comes to floating-point among other things) it
makes sense to provide a utility function that keeps all the boilerplate
contained; especially considering it makes it harder to accidentally
misuse std::memcpy (such as accidentally transposing arguments, etc).
Another benefit of this function is that it doesn't require separating
declarations from assignments, allowing variables to be declared const.
This makes the scenario of of uninitialized variables being used less
likely to occur.
As of VS 15.7, these seem to have been removed. Given we shouldn't have
been using these for some time, just replace them with the standard
library equivalent.
This fixes building on Windows with VS 15.7
Keeps all of the floating-point utility functions in their own file to
keep them all together. This also provides a place for other
general-purpose floating-point functions to be added in the future,
which will be necessary when improving the flag-setting within the
interpreter.
FPSCR.FEX is supposed to be a logical OR of all floating-point exception
bits masked by their respective enable bits.
Currently UpdateFPSCR() isn't called by anything in the interpreter
except for mcrfs and mffs, so this doesn't alter existing behavior that much.
However, this will be necessary in future PRs when making the interpreter more
accurate in how it sets flags.
Prevent implicit conversions to UReg_FPSCR. Given the semantics of a
random magic value and the FPSCR are different, make explicit
conversions a requirement to signify intent.
The MSR.LE bit is supposed to be set to the value of MSR.ILE upon
entering an exception vector to control whether the environment in said
vector operates as little endian or big endian. If this bit is ORed into
the LE bit, then the scenario of operating in little endian but wanting
to take exceptions in big endian will be incorrectly handled.
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