This is a regression causing lots of cached diagnostics tests not
functioning since the cached diagnostics processors are not initialized
for those tests which are supposed to test diagnostics caching.
The regression is caused by the fix that the typecheck module interface
job need to run a typecheck job in the sub-invocation. Now the typecheck
module interface job is correctly setup to avoid diagnostics about
unsupported file system error.
Improve swift dependency scanner by validating and selecting dependency
module into scanner. This provides benefits that:
* Build system does not need to schedule interface compilation task if
the candidate module is picked, it can just use the candidate module
directly.
* There is no need for forwarding module in the explicit module build.
Since the build system is coordinating the build, there is no need for
the forwarding module in the module cache to avoid duplicated work,
* This also correctly supports all the module loading modes in the
dependency scanner.
This is achieved by only adding validate and up-to-date binary module as
the candidate module for swift interface module dependency. This allows
caching build to construct the correct dependency in the CAS. If there
is a candidate module for the interface module, dependency scanner will
return a binary module dependency in the dependency graph.
The legacy behavior is mostly preserved with a hidden frontend flag
`-no-scanner-module-validation`, while the scanner output is mostly
interchangeable with new scanner behavior with `prefer-interface` module
loading mode except the candidate module will not be returned.
rdar://123711823
Fix a stack-use-after-scope in the CachedDiagnostics when the
DiagnosticInfo entry that is getting deserialized has ChildDiagnostics.
There are some fields in the DiagnosticInfo are not owned by the
DiagnosticsInfo itself. While the callback during the deserialization
ensures those fields are still alive for the top level DiagnosticInfo
when it gets used, it is not true for any child diagnostics info inside.
rdar://123846525
Improve caching related tests to make them faster and test the situation
closer to what actually happens during explicit module build. Most
noticable changes are:
* Avoid swift stdlib dependency during the tests to save time
* Use dependency scanner output to construct test cases
* Update old test cases that try to simulate caching from file system
inputs to using only CAS inputs.
Teach CachedDiagnosticsProcessor to replay diagnostics for all consumers
with a different path using a path prefix map. This allows diagnostics
to be replayed for the actual path on disk after the scanner
canonicalized the path for compilation.
Rename `-enable-cas` to `-compile-cache-job` to align with clang option
names and promote that to a new driver only flag.
Few other additions to driver flag for caching behaviors:
* `-compile-cache-remarks`: now cache hit/miss remarks are guarded behind
this flag
* `-compile-cache-skip`: skip replaying from the cache. Useful as a
debugging tool to do the compilation using CAS inputs even the output
is a hit from the cache.
Add a CachedDiagnosticsProcessor that is a DiagConsumer can capture all
the diagnostics during a compilation, serialized them into CAS with a
format that can be replayed without re-compiling.
