Simple calls to `List.generate` are expanded into a list allocation
and a loop. This generates better code for several reasons:
- There is no overhead for the function argument (closure allocation,
closure type, closure class)
- Global type inference is more precise since each List.generate list
is tracked separately, and the assignments in the loop give better
inference to the collection's element type.
To get precise element type inference, there are two new JSArray
constructors. Global type inference starts with the element type being
bottom for these elements, avoiding spurious nulls in the inferred
type.
Change-Id: I5efb90651ae3f9eb2e81af556704960cdf0b75c5
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/168770
Commit-Queue: Stephen Adams <sra@google.com>
Reviewed-by: Johnni Winther <johnniwinther@google.com>
`List.of` avoids per-element checks and no longer forwards to
the more expensive `List.from`.
Global type inference infers `List.of` and `List.from` as new
list allocations.
Bug: 40211
Bug: 32937
Change-Id: I54746610a1b0089ec54e43459301720105f872ef
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/170127
Commit-Queue: Stephen Adams <sra@google.com>
Reviewed-by: Mayank Patke <fishythefish@google.com>
Use the 'growable:' argument or its absence to pick a better type for
List.of, List.from, List.generate, List.empty and List.filled.
Fixes a bug where it was assumed that List.filled was always fixed length.
Slightly better type analysis on some apps, but nothing that is measurable on benchmarks.
Change-Id: Ibe029a93488412956273fc981f626d33bd295386
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/163132
Commit-Queue: Stephen Adams <sra@google.com>
Reviewed-by: Mayank Patke <fishythefish@google.com>
Stephen Adams