In the current ongoing effort for sourcemod to fully support 64 bits, we are introducing "virtual address".
# Explanation
Because SourcePawn does not yet support a 64 bits-wide type it's been impossible for any plugins to hold addresses in regular 32-bits wide variable.
A first attempt at solving this issue was made in commit ce1a4dcac0 therein dubbed "PseudoAddress", however this turned out to be an unsatisfactory solution, as any 'high' address if offsetted could turn invalid (or outright be impossible to map).
This leaves us with three alternatives :
- New type
- Convert Address into a handle
- Virtual Address
A new type is the most destructive solution, as it entails breaking every single Address related method. While that solution is still not off the table, we're reserving it as the last attempt should this commit fail.
Converting into a handle type is a good compromise between a brand new type whilst also preserving the Address methods. However, this comes with two issues: the first being that you can no longer offset Address, the second is that we would require authors to free the handle type which will be very confusing. This will likely not be implemented.
# Virtual address
Under a reasonable assumption, we've noted that the average plugin is unlikely to play with more than 4 GB of memory; this shouldn't be too surprising as all valve games were once 32bits and therefore limited to 4GB. Assuming this stays mostly true and a plugin isn't interested with the mapped memory of lesser known modules (like soundlib or matlib), it is fair to assume plugins are unlikely to access more than 4GB of mapped memory. Working with this in mind, we map the memory the plugins are likely to access to our custom virtual address ranges (from 0 to 4Gb, the values of which can fit on 32bits variable). If any memory was missed and plugins were to try an access it later those ranges will be late-mapped to our virtual address ranges until we run out of them.
In order to use virtual addressing, whether on 32 bits or 64 bits. Plugins must now "#include <virtual_address>", as well as use the new SDKCall_VirtualAddress, SDKType_VirtualAddress, LoadAddressFromAddress & StoreAddressToAddress where it's appropriate to.
This is a pretty big diff because SourceMod had lots of multi-arch
workarounds that can now go away. I've also changed 'x64' to 'x86_64' in
many places since this is how AMBuild normalizes it, and it's far too
late to pick the shorter string, so we might as well suck it up.
The --target-archs parameter has been replaced with --targets. It works
the same way.
The default behavior for SDK inclusion is now "present" instead of
"all" since this lowers the burden of storing many SDKs. Official builds
will still be made with --sdks=all.
This patch removes almost all of the existing platform-specific
ThreadSupport code, as well as code derived from it. It is now
implemented on top of C++11 threads and is much simpler.
This is the first inclusion of STL in SourceMod. Mac and Windows are
allowed to dynamically link to their respective implementations. On
Linux, libstdc++ is statically linked, except in the cases where it was
already dynamically linked (csgo, blade).
IEventSignal has been retained because sourcemod-curl-extension relies
on it. As written, it is impossible to use as a condition variable,
because the caller does not have access to the underlying mutex. There
is no way to make this API safe or non-racy, so extensions relying on
it should switch to C++11 threads.
ThreadWorker is now pared down and does not interact or inherit from
BaseWorker in any way. Basic functionality has been tested. Since it is
not used anywhere in SourceMod, or seemingly in any repository on
GitHub, it's unclear whether it should even exist. But it has been
tested in this patch.
This change bumps the minimum macOS version to OS X 10.7, and the
minimum C++ standard level to C++14.
This simplifies non-sdk build scripts by removing their loops over SM.archs. Instead the top-level
build script will re-evaluate them for each architecture.
* Create DatabaseConfBuilder & remove locking
* Remove all refcounting
This is part 1/n in regards to this PR's rework
* Move db conf lookup out of RunThreadPart
* Return default configuration for failed lookups
* RefPtr members & stop leaks
* fix uint comparison warning
* Create FrameIterator type
This commit adds the FrameIterator type to core sm along with a few
methods around getting the information for each frame.
* Fix incorrect documentation
[skip ci]
* Implement KyleS's Changes
* A nit
This has three major changes to SourcePawn. First, the API now supports the concept of "exceptions". The exception state is a global property of an instance of the SourcePawn VM. Exceptions can be caught or suppressed. Many places in SourceMod have been updated to check exceptions instead of errors.
The new API obsoletes major parts of the embedder API - all but one method of invoking functions is obsoleted, and the debug interface has been scrapped. Extensions using the native API will not be affected, however, ThrowNativeError has been deprecated in favor of ReportError.
Second, the SourcePawn concept of a "stack" has been unified at the API level. A stack frame iterator now iterates over all SourcePawn invocations, rather than the topmost plugin. This makes error handling more consistent and removes another dependency on context-per-plugin.
Finally, the implementation of stack frames has been changed dramatically. Rather than maintain a complicated and expensive return pointer stack, we now rely on the implicit one provided by the CPU. The stack frame iterator now walks the JIT stack directly. This removes many unnecessary bookkeeping instructions from the generated code, in particular making the CALL instruction 40% faster.
These changes required some fair surgery to the JIT. Its error paths are now slightly more complicated, as they have to throw an exception rather than return an error code. In addition, any path that can throw an exception is now responsible for creating an "exit frame", which exists to tell the stack frame iterator about transitions from the JIT to the VM.
