C++ no-op functions can't optimize out the predicate arguments in all cases.
This was causing a problem where zero cost assertions weren't actually zero cost.
The only way to resolve this is to actually use macros sadly enough.
This will give a fairly hefty performance uplift with anything operating on IR.
Configuration mapping was duplicated between three different tables.
Additionally default configuration values were strewn about. Making it confusing as to what the default value would end up being
Adds a new ConfigValues.inl header that defines a few things right next to each other.
Defines the enum name as usual.
Defines the JSON config option name.
Defines the Environment config option name
Defines the default value that the configuration should be
Patch moves HandleSIGSEGV in HostFactory.cpp to a non-frontend host signal handler, then registers its own frontend signal handler to catch unhandled segfaults.
Sadly these things can't be split without breaking functionality so it
turns in to a bit of a mess.
SyscallHandler is very much something that is a Linux only construct and
shouldn't be in FEXCore itself. Lets the frontend register a
Syscallhandler with FEXCore. FEXCore itself is then aware of the current
syscall ABI and handles the ABI in an optimal fashion.
So it is not a 100% clean break otherwise we would lose performance.
The SignalDelegator then needs to move to the frontend since the
SyscallHandler requires it for signal based syscalls.
The CPU backend signal handling still needs to happen in FEXCore because
it is a very tight coupling with the CPU backend.
Once we need to support more Signal handling we can give the backends
cleaner support to select which specific OS handler to handle.
Instead of having the configuration being loaded and stored in to a
frontend system. First moves the backing store of the configuration in
to FEXCore.
Each layer that is constructed then loads its particular configuration.
After the layers are loaded, then a meta layer is constructed that
merges the layers flat.
This means we will no longer hit the problem where a configuration is
stored in the "main" configuration file, then environment and arguments
passed manage to overwrite it.
The order of the layers going from inner most layer to outer most, with
outermost overwriting previous layer configurations is as follows:
Main < Global application < Local application < Arguments < Environment
One step that needs to be changed in the future is that FEXCore can then
just load its configuration from the layers directly since the data is
in FEXCore now. This will be reserved for a future change so we are less
disruptive.
- InvalidateFlags pseudo-op is a hint for the Dead Flags Elimination pass that flags are not needed past that point
- Adds a new option, --abi-local-flags, that invalidates the flags on CALLs or RETs. This might break code that doesn't follow the ABI rules.
All the previous fixed offset problems are now fixed so we can flick
this on.
We still allocate memory regions at fixed addresses, but due to
enforcing pie this is fine.
This requires implementing custom ASM dispatchers for the interpreter
side of things so it works correctly.
Allows all of our CPU backends to safely support signaling.
This is a bit of a nightmare change and requires rethinking logic about
debugging in some instances.
Ryan Houdek