commit 34052bf2bbe2477d22bc4ef96b774067a86f68e3
author Anna Gringauze <annagrin@google.com> Thu Sep 03 03:05:13 2020 +0000
committer commit-bot@chromium.org <commit-bot@chromium.org> Thu Sep 03 03:05:13 2020 +0000
tree 6f79cadd39c4275acbba70029f3570061cd92197
parent 0c5f2a35328fc0b285c01710b6ea7f3a7d2e0713

Add expression evaluation to ddc for google3

- Move expression evaluation to ddc in preparation for google3
- Added server to ddc to handle update and compileExpression requests
- Added tests
- Added 'experimental-output-compiled-kernel' option to ddc to generate
  full kernel files only for compiled libraries, and store with
  '.full.dill' extension
- Added AssetFileSystem to communicate to the asset server in the
  debugger
- Made expression_compiler_worker work with full kernel files,
  so removed invalidation of current file to improve performance
- Made expression_compiler_worker reuse already loaded imports
  to avoid reading them from source in the incremental compiler
- Updated tests to work with DDC (for simulating webdev)
- Disabled tests that work with bazel kernel worker for now
  as it does not generate full dill files yet
- Addressed code review comments from the prototype version:
  https://dart-review.googlesource.com/c/sdk/+/157005

Details:

Currently, in flutter tools, expression evaluation is supported via
expression compilation, which is done by the incremental compiler in
the frontend server. The same incremental compiler is used for initial
application compilation, incremental code compilation for hot reload,
and any number of expression compilation requests.

In google3, the apps are typically too large to be compiled as a whole
in memory by the frontend server. Build in google3 is currently done by
blaze, as a distributed build using a task dependency graph. Build tasks
output kernel outline files as an interface between components produced
by individual tasks.

We are proposing an implementation of the expression compilation in
google3 that is taking advantage of full kernel files produced by the
build (supporting build changes to follow). This change introduces a
small server based on dev_compiler, which can handle following requests:

- update: load full kernel for given modules (done on app start)
- compileExpression: compile expression in a given library and module
  (done when paused on a breakpoint)

Expression compilation uses previously loaded kernel files for the
application component and its dependencies to compile an expression.


Change-Id: Icf73868069faf3a2eb6d43ba78e459f8457e9e35
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/160944
Reviewed-by: Nicholas Shahan <nshahan@google.com>
Reviewed-by: Gary Roumanis <grouma@google.com>
Reviewed-by: Jens Johansen <jensj@google.com>
Reviewed-by: Jake Macdonald <jakemac@google.com>
Commit-Queue: Anna Gringauze <annagrin@google.com>