From 39f2bd737bb0b9446b4d241aa76fcb87d7e77278 Mon Sep 17 00:00:00 2001 From: Austin Clements Date: Tue, 9 Feb 2016 17:34:14 -0500 Subject: [PATCH] runtime: improve initSpan documentation Change-Id: I9c45aad1c35a99da4c3b8990649dcd962fd23b81 Reviewed-on: https://go-review.googlesource.com/19631 Reviewed-by: Rick Hudson Run-TryBot: Austin Clements TryBot-Result: Gobot Gobot --- src/runtime/mbitmap.go | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/src/runtime/mbitmap.go b/src/runtime/mbitmap.go index 35fc82bf4a..04992890a1 100644 --- a/src/runtime/mbitmap.go +++ b/src/runtime/mbitmap.go @@ -494,6 +494,10 @@ func typeBitsBulkBarrier(typ *_type, p, size uintptr) { // TODO(rsc): Perhaps introduce a different heapBitsSpan type. // initSpan initializes the heap bitmap for a span. +// It clears all mark and checkmark bits. +// If this is a span of pointer-sized objects, it initializes all +// words to pointer (and there are no dead bits). +// Otherwise, it initializes all words to scalar/dead. func (h heapBits) initSpan(size, n, total uintptr) { if total%heapBitmapScale != 0 { throw("initSpan: unaligned length")