All of this is in service of working around a pile of deficiencies in LLVM's Module Linker, and LLVMContext abstractions. And because we're just gonna scrap this code soon anyways, it's probably not worth the effort to push on these bugs to block the broader cleanup here.
The LLVM Linker currently does not support linking modules allocated in different contexts. This appears to be motivated in part by LLVM's lack of a facility to clone a module from one context to another. This, in turn, appears to be motivated in part by LLVMContext's lack of a robust notion of identity - which makes it harder than it needs to be to detect the mismatch.
However, it is not impossible to clone a module across contexts. We need to get creative and round-trip the module through some serialization layer. Out of convenience, that layer is currently textual IR, though bitcode would work equally well.
Given that it is no longer under the caller's control which LLVMContext we generate code in, put all the above together to arrive at an egregious hack that clones the module into the LLVMContext the REPL expects.
- Check the target triple at runtime to decide whether to use the fallback.
- Change isInResourceDir to actually check the resource dir.
- Use ArrayRef<std::string> instead of std::vector<std::string>.
Provides a new fallback for Process arguments for those instances where we do
not own main (e.g. Frameworks, Objective-C owns main.m or main.c, etc.). This
includes a number of platform-specific specializations of argument grabbing
logic and a new thread-safe interface to Process.unsafeArgv.
main() | _NSGetArgc/_NSGetArgv | /proc/self/cmdline | __argc/__argv
--------|--------------------------|------------------------|---------------
Scripts | OS X, iOS, tvOS, watchOS | Linux, FreeBSD, Cygwin | Windows
For interpreted Swift where we must filter out the arguments we now do so by
loading the standard library and calling into new SPI to override the arguments
that would have been grabbed by the runtime. This implementation completely
subsumes the use of the entry point '_stdlib_didEnterMain' and it will be
removed in a future commit.
Correct format:
```
//===--- Name of file - Description ----------------------------*- Lang -*-===//
```
Notes:
* Comment line should be exactly 80 chars.
* Padding: Pad with dashes after "Description" to reach 80 chars.
* "Name of file", "Description" and "Lang" are all optional.
* In case of missing "Lang": drop the "-*-" markers.
* In case of missing space: drop one, two or three dashes before "Name of file".
No intended functionality change, although this may make it easier to
get the REPL up and running on Linux. This is still useful for compiler
hackers even if it's not an end-user feature.
Swift SVN r31502
