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runtime: use spanOf* more widely

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The logic in the spanOf* functions is open-coded in a lot of places
right now. Replace these with calls to the spanOf* functions.

Change-Id: I3cc996aceb9a529b60fea7ec6fef22008c012978
Reviewed-on: https://go-review.googlesource.com/85880
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>
This commit is contained in:
Austin Clements 2017-12-04 11:02:59 -05:00
parent a90f9a00ca
commit 4de468621a
4 changed files with 20 additions and 35 deletions
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31
src/runtime/mheap.go
View file

@ -390,15 +390,7 @@ func (sc spanClass) noscan() bool {
//go:nowritebarrier
//go:nosplit
func inheap(b uintptr) bool {
if b == 0 || b < mheap_.arena_start || b >= mheap_.arena_used {
return false
}
// Not a beginning of a block, consult span table to find the block beginning.
s := mheap_.spans[(b-mheap_.arena_start)>>_PageShift]
if s == nil || b < s.base() || b >= s.limit || s.state != mSpanInUse {
return false
}
return true
return spanOfHeap(b) != nil
}
// inHeapOrStack is a variant of inheap that returns true for pointers
@ -407,11 +399,7 @@ func inheap(b uintptr) bool {
//go:nowritebarrier
//go:nosplit
func inHeapOrStack(b uintptr) bool {
if b == 0 || b < mheap_.arena_start || b >= mheap_.arena_used {
return false
}
// Not a beginning of a block, consult span table to find the block beginning.
s := mheap_.spans[(b-mheap_.arena_start)>>_PageShift]
s := spanOf(b)
if s == nil || b < s.base() {
return false
}
@ -423,9 +411,6 @@ func inHeapOrStack(b uintptr) bool {
}
}
// TODO: spanOf and spanOfUnchecked are open-coded in a lot of places.
// Use the functions instead.
// spanOf returns the span of p. If p does not point into the heap
// arena or no span has ever contained p, spanOf returns nil.
//
@ -433,6 +418,10 @@ func inHeapOrStack(b uintptr) bool {
// span that does *not* contain p. If this is a possibility, the
// caller should either call spanOfHeap or check the span bounds
// explicitly.
//
// Must be nosplit because it has callers that are nosplit.
//
//go:nosplit
func spanOf(p uintptr) *mspan {
if p == 0 || p < mheap_.arena_start || p >= mheap_.arena_used {
return nil
@ -443,12 +432,20 @@ func spanOf(p uintptr) *mspan {
// spanOfUnchecked is equivalent to spanOf, but the caller must ensure
// that p points into the heap (that is, mheap_.arena_start <= p <
// mheap_.arena_used).
//
// Must be nosplit because it has callers that are nosplit.
//
//go:nosplit
func spanOfUnchecked(p uintptr) *mspan {
return mheap_.spans[(p-mheap_.arena_start)>>_PageShift]
}
// spanOfHeap is like spanOf, but returns nil if p does not point to a
// heap object.
//
// Must be nosplit because it has callers that are nosplit.
//
//go:nosplit
func spanOfHeap(p uintptr) *mspan {
s := spanOf(p)
// If p is not allocated, it may point to a stale span, so we