For the multiple-files mode -emit-pch is still invoked in separate frontend invocation but with using a persistent PCH.
Subsequent frontend invocations use the persistent PCH but they don't need to validate it.
For all-files mode (e.g. WMO) the frontend invocation uses a persistent PCH that it also validates.
- Add CompilerInvocation::getPCHHash
This will be used when creating a unique filename for a persistent
precompiled bridging header.
- Automatically generate and use a precompiled briding header
When we're given both -import-objc-header and -pch-output-dir
arguments, we will try to:
- Validate what we think the PCH filename should be for the bridging
header, based on the Swift PCH hash and the clang module hash.
- If we're successful, we'll just use it.
- If it's out of date or something else is wrong, we'll try to
emit it.
- This gives us a single filename which we can `stat` to check for the
validity of our code completion cache, which is keyed off of module
name, module filename, and module file age.
- Cache code completion results from imported modules
If we just have a single .PCH file imported, we can use that file as
part of the key used to cache declarations in a module. Because
multiple files can contribute to the __ObjC module, we've always given
it the phony filename "<imports>", which never exists, so `stat`-ing it
always fails and we never cache declarations in it.
This is extremely problematic for projects with huge bridging headers.
In the case where we have a single PCH import, this can bring warm code
completion times down to about 500ms from over 2-3s, so it can provide a
nice performance win for IDEs.
- Add a new test that performs two code-completion requests with a bridging header.
- Add some -pch-output-dir flags to existing SourceKit tests that import a bridging
header.
rdar://problem/31198982
Most tests were using %swift or similar substitutions, which did not
include the target triple and SDK. The driver was defaulting to the
host OS. Thus, we could not run the tests when the standard library was
not built for OS X.
Swift SVN r24504
This keeps CInt (and related type aliases) in the stdlib, and keeps the clang importer
using them, but has it look through one level of the type alias to get to the underlying
type.
The upshot of this is that we now import things like exit (as a random example) as
"func exit(Int32)" instead of "func exit(CInt)".
Swift SVN r19224
