For now, the accessors have been underscored as `_read` and `_modify`.
I'll prepare an evolution proposal for this feature which should allow
us to remove the underscores or, y'know, rename them to `purple` and
`lettuce`.
`_read` accessors do not make any effort yet to avoid copying the
value being yielded. I'll work on it in follow-up patches.
Opaque accesses to properties and subscripts defined with `_modify`
accessors will use an inefficient `materializeForSet` pattern that
materializes the value to a temporary instead of accessing it in-place.
That will be fixed by migrating to `modify` over `materializeForSet`,
which is next up after the `read` optimizations.
SIL ownership verification doesn't pass yet for the test cases here
because of a general fault in SILGen where borrows can outlive their
borrowed value due to being cleaned up on the general cleanup stack
when the borrowed value is cleaned up on the formal-access stack.
Michael, Andy, and I discussed various ways to fix this, but it seems
clear to me that it's not in any way specific to coroutine accesses.
rdar://35399664
Naming the bit-field structs is a significant readability improvement
because it's very clear that you shouldn't touch e.g. Bits.Token
without having checked/asserted that you're in a token case.
The assertions are all in statement context (which was obvious
because the NDEBUG versions all included semicolons), so there's no
reason not to use the traditional `do { } while (false)` trick instead
of a statement-expression.
This also clears up some warnings in atypical build configurations.
The existing libSyntax infrastructure uses external python
dictionaries to share logic between C++ and Swift implementations.
This patch teaches trivia kinds to adapt to this infrastructure
as well.
Make the quoted parameters more portable. This is needed in order to
support building swift on Windows. Simplify the declaration of the
flags and do a small formatting clean up. This ensures that the ninja
generation gets the command line invocation correct.
Introduced SyntaxArena for managing memory and cache.
SyntaxArena holds BumpPtrAllocator as a allocation storage.
RawSyntax is now able to be constructed with normal heap allocation, or
by SyntaxArena. RawSyntax has ManualMemory flag which indicates it's managed by
SyntaxArena. If the flag is true, its Retain()/Release() is no-op thus it's
never destructed by IntrusiveRefCntPtr.
This speedups the memory allocation for RawSyntax.
Also, in Syntax parsing, "token" RawSyntax is reused if:
a) It's not string literal with >16 length; and
b) It doesn't contain random text trivia (e.g. comment).
This reduces the overall allocation cost.
The enhanced SourceKitd requests are EditorOpen and EdtiorReplaceText. In these two requests, the clients can specify a flag "key. enablesyntaxtree = 1" to get a serialize libSyntax tree with the response.
To help this integration, we added a function in SyntaxParsingContext to explicitly finalize the creation of a SourceFileSyntax to incorporate the fact that SourceKit needs the tree before its destroying the parser instance.
To test this integration, we diff the syntax tree serialized from the frontend action and the tree serialized from a SourceKitd response. They should be identical.
With more syntax nodes being specialized, we'd like this
straight-forward way to pinpoint unknown entities. This diagnostics
is only issued in -emit-syntax frontend action and swift-syntax-test
invocation.
This patch reworks the line-directive command line argument for gyb to
take in a python-style format string with `line` and `file` variables
to be substituted.
libSyntax nodes don't maintain absolute source location on each
individual node. Instead, the absolute locations are calculated on
demand with a given root by accumulating the length of all the other
nodes before the target node. This bridging is important for issuing
diagnostics from libSyntax entities.
With the observation that our current implementation of the source
location calculation has multiple bugs, this patch re-implemented this
bridging by using the newly-added syntax visitor. Also, we moved the function
from RawSyntax to Syntax for better visibility.
To test this source location calculation, we added a new action in
swift-syntax-test. This action parses a given file as a
SourceFileSyntax, calculates the absolute location of the
EOF token in the SourceFileSyntax, and dump the buffer from the start
of the input file to the absolute location of the EOF. Finally, we compare
the dump with the original input to ensure they are identical.
This allows the root context to have a separate place to keep track of
the global data that each sub-context can access to, for instance,
SourceFile, DiagnosticEngine, etc.
