This moves pattern variable assignments of fully matched expressions into the case body. This will help backends (dart2js in particular) to reason about the code flow.
Closes#54115
Change-Id: I598a384a829f16e91ab2d6a309499cf20b9cc121
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/339122
Commit-Queue: Johnni Winther <johnniwinther@google.com>
Reviewed-by: Jens Johansen <jensj@google.com>
This changes the pattern matching lowering to avoid using late final variables (or lowerings thereof) and instead inline the initializer where used. This avoids generating closures that are hard for backends to reason about and optimize.
Closes#52805Closes#53804
Change-Id: Ia887446dd4d4475d05cf852c812bfe4b851de261
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/338860
Commit-Queue: Johnni Winther <johnniwinther@google.com>
Reviewed-by: Jens Johansen <jensj@google.com>
This changes the pattern lowering to use unchecked AsExpression
instead of promoted VariableGet when this occurs within a late
cache variable initializer. This is done to avoid promoted variables
that violate the (otherwise used) conservative reasoning about the
execution order of closures.
The unchecked AsExpressions are now shown in the ast-to-text.
Change-Id: I4fa6813f3b5cc73d9cdac17054de59e5d4b8ce7d
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/307044
Reviewed-by: Chloe Stefantsova <cstefantsova@google.com>
Commit-Queue: Johnni Winther <johnniwinther@google.com>
Reviewed-by: Nate Biggs <natebiggs@google.com>
In unsound null safety a throw expression is added as the last case
of switches without default to ensure that `null` doesn't fall through.
A break statement needs to be inserted in the last case if it doesn't
itself terminate.
Closes#51957
Change-Id: Ib63059aa2a00ebf1d7e49941af3b1c8acfc696f4
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/293603
Commit-Queue: Johnni Winther <johnniwinther@google.com>
Reviewed-by: Chloe Stefantsova <cstefantsova@google.com>
This flag is set when a variable declaration is moved earlier in
order to be available for subsequent code that couldn't contain
its declaration. For instance variables declared in patterns which
needs to be declared before the matching expressions that initialize
them.
TEST=existing expectations tests
Change-Id: I80ab1138f08f725f3e01905c1a57a1483f809328
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/291820
Commit-Queue: Johnni Winther <johnniwinther@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Chloe Stefantsova <cstefantsova@google.com>
Johnni Winther