commit 787446213c72b18dc016bc98018bb90335c6a215
author Tess Strickland <sstrickl@google.com> Mon Aug 17 08:58:08 2020 +0000
committer commit-bot@chromium.org <commit-bot@chromium.org> Mon Aug 17 08:58:08 2020 +0000
tree e1af499e9021f3947de37a191ff3d3f48831fb7a
parent 07a440901e874d026e92e2774c69e37292a5217f

[vm/compiler] Move argument shape (not type) checks out of closures.

This CL performs the following checks in the invoke field dispatcher for
dynamic closure calls when lazy dispatchers are enabled:

* The provided function type arguments vector (if any) has the correct
  length.

* No function type arguments should be provided if the closure has
  delayed type arguments.

* All required arguments (positional in all modes, named in appropriate
  null safety modes) have been provided by the caller.

* If there are optional positional arguments, an appropriate number
  has been provided.

* If there are optional named arguments, their names are valid.

Since the runtime already handles checking the argument shapes when lazy
dispatchers are disabled, these checks are now completely removed from
closure bodies in all cases. Thus, the only remaining checks in closure
bodies are the type checks performed by AssertSubtype and
AssertAssignable when lazy dispatchers are enabled.

Changes in the Flutter Gallery:

* ARM7, release: -3.61% instructions, -2.19% total
* ARM7, sizeopt: -3.62% instructions, -2.55% total
* ARM8, release: -3.66% instructions, -1.98% total
* ARM8, sizeopt: -3.65% instructions, -2.37% total

Most of these changes are already exercised by existing tests such as
(but not limited to):

* corelib{,_2}/dynamic_nosuchmethod_test
* language{,_2}/call/call_test
* language{,_2}/closure/tearoff_dynamic_test
* language{,_2}/generic/function_bounds_test
* language{,_2}/parameter/named_with_conversions_test
* language{,_2}/vm/no_such_args_error_message_vm_test

I've added one test to specifically check the interaction between
dynamic calls and required named parameters. There is some coverage in
other NNBD tests, but those are not directly focused on testing this
specifically.

Other changes:

* Adds initial cached ranges for certain BinarySmiOp and ShiftIntegerOp
  instructions when the RHS is a constant, to avoid false negatives for
  deoptimization and throw checks prior to range analysis.

* Adds new slots for various Function fields.

* Adds the ability to define unboxed native slots, which are always
  unboxed after retrieval even in unoptimized code. In the first
  iteration, the backend only handles loads from Uint32 unboxed native
  slots. Part of https://github.com/dart-lang/sdk/issues/42793.

* Removed the special handling for loading from non-nullable int fields
  in AOT compilation. Instead, their treatment is unified with the
  treatment of the new unboxed native fields, since the source field is
  always unboxed and the result of the load is also always unboxed, as
  code involving them is always optimized.

Bug: https://github.com/dart-lang/sdk/issues/40813
Change-Id: Ia02aa3e872c1fefd906fd67b55021ea1797556e4
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/155604
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>