github.com/bir3/gocompiler@v0.9.2202/src/internal/coverage/calloc/batchcounteralloc.go (about)

     1  // Copyright 2022 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  package calloc
     6  
     7  // This package contains a simple "batch" allocator for allocating
     8  // coverage counters (slices of uint32 basically), for working with
     9  // coverage data files. Collections of counter arrays tend to all be
    10  // live/dead over the same time period, so a good fit for batch
    11  // allocation.
    12  
    13  type BatchCounterAlloc struct {
    14  	pool []uint32
    15  }
    16  
    17  func (ca *BatchCounterAlloc) AllocateCounters(n int) []uint32 {
    18  	const chunk = 8192
    19  	if n > cap(ca.pool) {
    20  		siz := chunk
    21  		if n > chunk {
    22  			siz = n
    23  		}
    24  		ca.pool = make([]uint32, siz)
    25  	}
    26  	rv := ca.pool[:n]
    27  	ca.pool = ca.pool[n:]
    28  	return rv
    29  }