From 3cbfcaa4ba898faba516fbb9f3debf4ceac1a557 Mon Sep 17 00:00:00 2001 From: Austin Clements Date: Sun, 2 Oct 2016 18:46:02 -0400 Subject: [PATCH] runtime: make mspan.isFree do what's on the tin Currently mspan.isFree technically returns whether the object was not allocated *during this cycle*. Fix it so it actually returns whether or not the object is allocated so the method is more generally useful (especially for debugging). It has one caller, which is carefully written to be insensitive to this distinction, but this lets us simplify this caller. Change-Id: I9d79cf784a56015e434961733093c1d8d03fc091 Reviewed-on: https://go-review.googlesource.com/30145 Run-TryBot: Austin Clements TryBot-Result: Gobot Gobot Reviewed-by: Rick Hudson --- src/runtime/heapdump.go | 2 +- src/runtime/mbitmap.go | 4 ++++ 2 files changed, 5 insertions(+), 1 deletion(-) diff --git a/src/runtime/heapdump.go b/src/runtime/heapdump.go index c317b5f969..f7d7aac2a7 100644 --- a/src/runtime/heapdump.go +++ b/src/runtime/heapdump.go @@ -474,7 +474,7 @@ func dumpobjs() { throw("freemark array doesn't have enough entries") } - for freeIndex := s.freeindex; freeIndex < s.nelems; freeIndex++ { + for freeIndex := uintptr(0); freeIndex < s.nelems; freeIndex++ { if s.isFree(freeIndex) { freemark[freeIndex] = true } diff --git a/src/runtime/mbitmap.go b/src/runtime/mbitmap.go index 3363cd0682..7171d3adbd 100644 --- a/src/runtime/mbitmap.go +++ b/src/runtime/mbitmap.go @@ -264,7 +264,11 @@ func (s *mspan) nextFreeIndex() uintptr { return result } +// isFree returns whether the index'th object in s is unallocated. func (s *mspan) isFree(index uintptr) bool { + if index < s.freeindex { + return false + } whichByte := index / 8 whichBit := index % 8 byteVal := *addb(s.allocBits, whichByte) -- 2.48.1