leaysgur
9f81002229
```js // input (semi: true) // oxfmt-ignore const a = x // before // oxfmt-ignore const a = x // after // oxfmt-ignore const a = x; ``` ```js // input (semi: false) let a = 1; // oxfmt-ignore [b].sort(); // before let a = 1 // oxfmt-ignore [b].sort(); // <- ASI failure // after let a = 1 // oxfmt-ignore ;[b].sort() // <- OK ```
Oxc allocations stats
This task keeps track of the number of system allocations as well as arena allocations and the total number of bytes allocated. This is used for monitoring possible regressions in allocations and improvements in memory usage.
Update the snapshots with cargo allocs.
Metrics
Recorded per file and per stage (parser, semantic, transformer, minifier, formatter):
file size- size of the source textsys allocs/sys reallocs/sys deallocs- system allocator activity during the stagesys alloc bytes- total bytes requested from the system allocator during the stage (allocation sizes plus reallocation growth)sys peak growth- high-water mark of live heap memory during the stage, relative to the live bytes when the stage started; captures transient heap the stage needs even when it frees it again before finishingarena allocs/arena reallocs- arena allocator activity during the stagearena size- bytes used in the arena at the end of the stage (cumulative: the arena is not reset between stages, so this includes the AST built by the parser)
Arena chunk allocations and deallocations are excluded from all sys metrics: chunk sizes are quantized and platform-dependent (whether an arena needs one more chunk depends on byte totals that vary across architectures), and for long-lived arenas chunk growth reflects the arena's history rather than the stage's own behavior. Arenas mark their chunk operations for the tracking allocator to skip.
Cross-platform reproducibility
Allocation counts are identical on all platforms: the task pins mimalloc as the global allocator and excludes arena chunk allocations from the system allocation counts. arena size is not exactly reproducible: type layout differs slightly across architectures (e.g. hashbrown's table control groups are 16 bytes on x86_64 vs 8 bytes on aarch64), which shifts arena byte totals by up to ~128 bytes per file. So that a snapshot generated on any platform passes CI on the others, the snapshots are YAML: cargo allocs parses the committed snapshot and keeps a byte metric's committed value when the measured one is within that metric's tolerance (arena size: 1024 bytes; sys alloc bytes and sys peak growth: 1%, minimum 4 kB); only differences beyond the tolerance rewrite the value.