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Diffstat (limited to 'libgo/go/runtime/hashmap.go')
-rw-r--r--libgo/go/runtime/hashmap.go307
1 files changed, 214 insertions, 93 deletions
diff --git a/libgo/go/runtime/hashmap.go b/libgo/go/runtime/hashmap.go
index 77b33f3..5b191d4 100644
--- a/libgo/go/runtime/hashmap.go
+++ b/libgo/go/runtime/hashmap.go
@@ -67,7 +67,7 @@ import (
//go:linkname mapaccess2 runtime.mapaccess2
//go:linkname mapaccess1_fat runtime.mapaccess1_fat
//go:linkname mapaccess2_fat runtime.mapaccess2_fat
-//go:linkname mapassign1 runtime.mapassign1
+//go:linkname mapassign runtime.mapassign
//go:linkname mapdelete runtime.mapdelete
//go:linkname mapiterinit runtime.mapiterinit
//go:linkname mapiternext runtime.mapiternext
@@ -106,9 +106,10 @@ const (
minTopHash = 4 // minimum tophash for a normal filled cell.
// flags
- iterator = 1 // there may be an iterator using buckets
- oldIterator = 2 // there may be an iterator using oldbuckets
- hashWriting = 4 // a goroutine is writing to the map
+ iterator = 1 // there may be an iterator using buckets
+ oldIterator = 2 // there may be an iterator using oldbuckets
+ hashWriting = 4 // a goroutine is writing to the map
+ sameSizeGrow = 8 // the current map growth is to a new map of the same size
// sentinel bucket ID for iterator checks
noCheck = 1<<(8*sys.PtrSize) - 1
@@ -118,10 +119,11 @@ const (
type hmap struct {
// Note: the format of the Hmap is encoded in ../../cmd/internal/gc/reflect.go and
// ../reflect/type.go. Don't change this structure without also changing that code!
- count int // # live cells == size of map. Must be first (used by len() builtin)
- flags uint8
- B uint8 // log_2 of # of buckets (can hold up to loadFactor * 2^B items)
- hash0 uint32 // hash seed
+ count int // # live cells == size of map. Must be first (used by len() builtin)
+ flags uint8
+ B uint8 // log_2 of # of buckets (can hold up to loadFactor * 2^B items)
+ noverflow uint16 // approximate number of overflow buckets; see incrnoverflow for details
+ hash0 uint32 // hash seed
buckets unsafe.Pointer // array of 2^B Buckets. may be nil if count==0.
oldbuckets unsafe.Pointer // previous bucket array of half the size, non-nil only when growing
@@ -141,6 +143,9 @@ type hmap struct {
// A bucket for a Go map.
type bmap struct {
+ // tophash generally contains the top byte of the hash value
+ // for each key in this bucket. If tophash[0] < minTopHash,
+ // tophash[0] is a bucket evacuation state instead.
tophash [bucketCnt]uint8
// Followed by bucketCnt keys and then bucketCnt values.
// NOTE: packing all the keys together and then all the values together makes the
@@ -178,7 +183,34 @@ func (b *bmap) overflow(t *maptype) *bmap {
return *(**bmap)(add(unsafe.Pointer(b), uintptr(t.bucketsize)-sys.PtrSize))
}
+// incrnoverflow increments h.noverflow.
+// noverflow counts the number of overflow buckets.
+// This is used to trigger same-size map growth.
+// See also tooManyOverflowBuckets.
+// To keep hmap small, noverflow is a uint16.
+// When there are few buckets, noverflow is an exact count.
+// When there are many buckets, noverflow is an approximate count.
+func (h *hmap) incrnoverflow() {
+ // We trigger same-size map growth if there are
+ // as many overflow buckets as buckets.
+ // We need to be able to count to 1<<h.B.
+ if h.B < 16 {
+ h.noverflow++
+ return
+ }
+ // Increment with probability 1/(1<<(h.B-15)).
+ // When we reach 1<<15 - 1, we will have approximately
+ // as many overflow buckets as buckets.
+ mask := uint32(1)<<(h.B-15) - 1
+ // Example: if h.B == 18, then mask == 7,
+ // and fastrand & 7 == 0 with probability 1/8.
+ if fastrand()&mask == 0 {
+ h.noverflow++
+ }
+}
+
func (h *hmap) setoverflow(t *maptype, b, ovf *bmap) {
+ h.incrnoverflow()
if t.bucket.kind&kindNoPointers != 0 {
h.createOverflow()
*h.overflow[0] = append(*h.overflow[0], ovf)
@@ -251,7 +283,7 @@ func makemap(t *maptype, hint int64, h *hmap, bucket unsafe.Pointer) *hmap {
// find size parameter which will hold the requested # of elements
B := uint8(0)
- for ; hint > bucketCnt && float32(hint) > loadFactor*float32(uintptr(1)<<B); B++ {
+ for ; overLoadFactor(hint, B); B++ {
}
// allocate initial hash table
@@ -269,10 +301,11 @@ func makemap(t *maptype, hint int64, h *hmap, bucket unsafe.Pointer) *hmap {
h.count = 0
h.B = B
h.flags = 0
- h.hash0 = fastrand1()
+ h.hash0 = fastrand()
h.buckets = buckets
h.oldbuckets = nil
h.nevacuate = 0
+ h.noverflow = 0
return h
}
@@ -304,7 +337,11 @@ func mapaccess1(t *maptype, h *hmap, key unsafe.Pointer) unsafe.Pointer {
m := uintptr(1)<<h.B - 1
b := (*bmap)(add(h.buckets, (hash&m)*uintptr(t.bucketsize)))
if c := h.oldbuckets; c != nil {
- oldb := (*bmap)(add(c, (hash&(m>>1))*uintptr(t.bucketsize)))
+ if !h.sameSizeGrow() {
+ // There used to be half as many buckets; mask down one more power of two.
+ m >>= 1
+ }
+ oldb := (*bmap)(add(c, (hash&m)*uintptr(t.bucketsize)))
if !evacuated(oldb) {
b = oldb
}
@@ -359,7 +396,11 @@ func mapaccess2(t *maptype, h *hmap, key unsafe.Pointer) (unsafe.Pointer, bool)
m := uintptr(1)<<h.B - 1
b := (*bmap)(unsafe.Pointer(uintptr(h.buckets) + (hash&m)*uintptr(t.bucketsize)))
if c := h.oldbuckets; c != nil {
- oldb := (*bmap)(unsafe.Pointer(uintptr(c) + (hash&(m>>1))*uintptr(t.bucketsize)))
+ if !h.sameSizeGrow() {
+ // There used to be half as many buckets; mask down one more power of two.
+ m >>= 1
+ }
+ oldb := (*bmap)(unsafe.Pointer(uintptr(c) + (hash&m)*uintptr(t.bucketsize)))
if !evacuated(oldb) {
b = oldb
}
@@ -397,16 +438,17 @@ func mapaccessK(t *maptype, h *hmap, key unsafe.Pointer) (unsafe.Pointer, unsafe
if h == nil || h.count == 0 {
return nil, nil
}
- if h.flags&hashWriting != 0 {
- throw("concurrent map read and map write")
- }
hashfn := t.key.hashfn
equalfn := t.key.equalfn
hash := hashfn(key, uintptr(h.hash0))
m := uintptr(1)<<h.B - 1
b := (*bmap)(unsafe.Pointer(uintptr(h.buckets) + (hash&m)*uintptr(t.bucketsize)))
if c := h.oldbuckets; c != nil {
- oldb := (*bmap)(unsafe.Pointer(uintptr(c) + (hash&(m>>1))*uintptr(t.bucketsize)))
+ if !h.sameSizeGrow() {
+ // There used to be half as many buckets; mask down one more power of two.
+ m >>= 1
+ }
+ oldb := (*bmap)(unsafe.Pointer(uintptr(c) + (hash&m)*uintptr(t.bucketsize)))
if !evacuated(oldb) {
b = oldb
}
@@ -455,20 +497,19 @@ func mapaccess2_fat(t *maptype, h *hmap, key, zero unsafe.Pointer) (unsafe.Point
return v, true
}
-func mapassign1(t *maptype, h *hmap, key unsafe.Pointer, val unsafe.Pointer) {
+// Like mapaccess, but allocates a slot for the key if it is not present in the map.
+func mapassign(t *maptype, h *hmap, key unsafe.Pointer) unsafe.Pointer {
if h == nil {
panic(plainError("assignment to entry in nil map"))
}
if raceenabled {
callerpc := getcallerpc(unsafe.Pointer( /* &t */ nil))
- pc := funcPC(mapassign1)
+ pc := funcPC(mapassign)
racewritepc(unsafe.Pointer(h), callerpc, pc)
raceReadObjectPC(t.key, key, callerpc, pc)
- raceReadObjectPC(t.elem, val, callerpc, pc)
}
if msanenabled {
msanread(key, t.key.size)
- msanread(val, t.elem.size)
}
if h.flags&hashWriting != 0 {
throw("concurrent map writes")
@@ -485,7 +526,7 @@ func mapassign1(t *maptype, h *hmap, key unsafe.Pointer, val unsafe.Pointer) {
again:
bucket := hash & (uintptr(1)<<h.B - 1)
- if h.oldbuckets != nil {
+ if h.growing() {
growWork(t, h, bucket)
}
b := (*bmap)(unsafe.Pointer(uintptr(h.buckets) + bucket*uintptr(t.bucketsize)))
@@ -496,35 +537,29 @@ again:
var inserti *uint8
var insertk unsafe.Pointer
- var insertv unsafe.Pointer
+ var val unsafe.Pointer
for {
for i := uintptr(0); i < bucketCnt; i++ {
if b.tophash[i] != top {
if b.tophash[i] == empty && inserti == nil {
inserti = &b.tophash[i]
insertk = add(unsafe.Pointer(b), dataOffset+i*uintptr(t.keysize))
- insertv = add(unsafe.Pointer(b), dataOffset+bucketCnt*uintptr(t.keysize)+i*uintptr(t.valuesize))
+ val = add(unsafe.Pointer(b), dataOffset+bucketCnt*uintptr(t.keysize)+i*uintptr(t.valuesize))
}
continue
}
k := add(unsafe.Pointer(b), dataOffset+i*uintptr(t.keysize))
- k2 := k
if t.indirectkey {
- k2 = *((*unsafe.Pointer)(k2))
+ k = *((*unsafe.Pointer)(k))
}
- if !equalfn(key, k2) {
+ if !equalfn(key, k) {
continue
}
// already have a mapping for key. Update it.
if t.needkeyupdate {
- typedmemmove(t.key, k2, key)
+ typedmemmove(t.key, k, key)
}
- v := add(unsafe.Pointer(b), dataOffset+bucketCnt*uintptr(t.keysize)+i*uintptr(t.valuesize))
- v2 := v
- if t.indirectvalue {
- v2 = *((*unsafe.Pointer)(v2))
- }
- typedmemmove(t.elem, v2, val)
+ val = add(unsafe.Pointer(b), dataOffset+bucketCnt*uintptr(t.keysize)+i*uintptr(t.valuesize))
goto done
}
ovf := b.overflow(t)
@@ -534,8 +569,11 @@ again:
b = ovf
}
- // did not find mapping for key. Allocate new cell & add entry.
- if float32(h.count) >= loadFactor*float32((uintptr(1)<<h.B)) && h.count >= bucketCnt {
+ // Did not find mapping for key. Allocate new cell & add entry.
+
+ // If we hit the max load factor or we have too many overflow buckets,
+ // and we're not already in the middle of growing, start growing.
+ if !h.growing() && (overLoadFactor(int64(h.count), h.B) || tooManyOverflowBuckets(h.noverflow, h.B)) {
hashGrow(t, h)
goto again // Growing the table invalidates everything, so try again
}
@@ -546,7 +584,7 @@ again:
h.setoverflow(t, b, newb)
inserti = &newb.tophash[0]
insertk = add(unsafe.Pointer(newb), dataOffset)
- insertv = add(insertk, bucketCnt*uintptr(t.keysize))
+ val = add(insertk, bucketCnt*uintptr(t.keysize))
}
// store new key/value at insert position
@@ -557,11 +595,9 @@ again:
}
if t.indirectvalue {
vmem := newobject(t.elem)
- *(*unsafe.Pointer)(insertv) = vmem
- insertv = vmem
+ *(*unsafe.Pointer)(val) = vmem
}
typedmemmove(t.key, insertk, key)
- typedmemmove(t.elem, insertv, val)
*inserti = top
h.count++
@@ -570,6 +606,10 @@ done:
throw("concurrent map writes")
}
h.flags &^= hashWriting
+ if t.indirectvalue {
+ val = *((*unsafe.Pointer)(val))
+ }
+ return val
}
func mapdelete(t *maptype, h *hmap, key unsafe.Pointer) {
@@ -594,7 +634,7 @@ func mapdelete(t *maptype, h *hmap, key unsafe.Pointer) {
equalfn := t.key.equalfn
hash := hashfn(key, uintptr(h.hash0))
bucket := hash & (uintptr(1)<<h.B - 1)
- if h.oldbuckets != nil {
+ if h.growing() {
growWork(t, h, bucket)
}
b := (*bmap)(unsafe.Pointer(uintptr(h.buckets) + bucket*uintptr(t.bucketsize)))
@@ -615,9 +655,17 @@ func mapdelete(t *maptype, h *hmap, key unsafe.Pointer) {
if !equalfn(key, k2) {
continue
}
- memclr(k, uintptr(t.keysize))
+ if t.indirectkey {
+ *(*unsafe.Pointer)(k) = nil
+ } else {
+ typedmemclr(t.key, k)
+ }
v := unsafe.Pointer(uintptr(unsafe.Pointer(b)) + dataOffset + bucketCnt*uintptr(t.keysize) + i*uintptr(t.valuesize))
- memclr(v, uintptr(t.valuesize))
+ if t.indirectvalue {
+ *(*unsafe.Pointer)(v) = nil
+ } else {
+ typedmemclr(t.elem, v)
+ }
b.tophash[i] = empty
h.count--
goto done
@@ -676,9 +724,9 @@ func mapiterinit(t *maptype, h *hmap, it *hiter) {
}
// decide where to start
- r := uintptr(fastrand1())
+ r := uintptr(fastrand())
if h.B > 31-bucketCntBits {
- r += uintptr(fastrand1()) << 31
+ r += uintptr(fastrand()) << 31
}
it.startBucket = r & (uintptr(1)<<h.B - 1)
it.offset = uint8(r >> h.B & (bucketCnt - 1))
@@ -703,6 +751,9 @@ func mapiternext(it *hiter) {
callerpc := getcallerpc(unsafe.Pointer( /* &it */ nil))
racereadpc(unsafe.Pointer(h), callerpc, funcPC(mapiternext))
}
+ if h.flags&hashWriting != 0 {
+ throw("concurrent map iteration and map write")
+ }
t := it.t
bucket := it.bucket
b := it.bptr
@@ -719,12 +770,12 @@ next:
it.value = nil
return
}
- if h.oldbuckets != nil && it.B == h.B {
+ if h.growing() && it.B == h.B {
// Iterator was started in the middle of a grow, and the grow isn't done yet.
// If the bucket we're looking at hasn't been filled in yet (i.e. the old
// bucket hasn't been evacuated) then we need to iterate through the old
// bucket and only return the ones that will be migrated to this bucket.
- oldbucket := bucket & (uintptr(1)<<(it.B-1) - 1)
+ oldbucket := bucket & it.h.oldbucketmask()
b = (*bmap)(add(h.oldbuckets, oldbucket*uintptr(t.bucketsize)))
if !evacuated(b) {
checkBucket = bucket
@@ -748,9 +799,9 @@ next:
k := add(unsafe.Pointer(b), dataOffset+uintptr(offi)*uintptr(t.keysize))
v := add(unsafe.Pointer(b), dataOffset+bucketCnt*uintptr(t.keysize)+uintptr(offi)*uintptr(t.valuesize))
if b.tophash[offi] != empty && b.tophash[offi] != evacuatedEmpty {
- if checkBucket != noCheck {
- // Special case: iterator was started during a grow and the
- // grow is not done yet. We're working on a bucket whose
+ if checkBucket != noCheck && !h.sameSizeGrow() {
+ // Special case: iterator was started during a grow to a larger size
+ // and the grow is not done yet. We're working on a bucket whose
// oldbucket has not been evacuated yet. Or at least, it wasn't
// evacuated when we started the bucket. So we're iterating
// through the oldbucket, skipping any keys that will go
@@ -836,21 +887,27 @@ next:
}
func hashGrow(t *maptype, h *hmap) {
- if h.oldbuckets != nil {
- throw("evacuation not done in time")
+ // If we've hit the load factor, get bigger.
+ // Otherwise, there are too many overflow buckets,
+ // so keep the same number of buckets and "grow" laterally.
+ bigger := uint8(1)
+ if !overLoadFactor(int64(h.count), h.B) {
+ bigger = 0
+ h.flags |= sameSizeGrow
}
oldbuckets := h.buckets
- newbuckets := newarray(t.bucket, 1<<(h.B+1))
+ newbuckets := newarray(t.bucket, 1<<(h.B+bigger))
flags := h.flags &^ (iterator | oldIterator)
if h.flags&iterator != 0 {
flags |= oldIterator
}
// commit the grow (atomic wrt gc)
- h.B++
+ h.B += bigger
h.flags = flags
h.oldbuckets = oldbuckets
h.buckets = newbuckets
h.nevacuate = 0
+ h.noverflow = 0
if h.overflow != nil {
// Promote current overflow buckets to the old generation.
@@ -865,36 +922,88 @@ func hashGrow(t *maptype, h *hmap) {
// by growWork() and evacuate().
}
-func growWork(t *maptype, h *hmap, bucket uintptr) {
- noldbuckets := uintptr(1) << (h.B - 1)
+// overLoadFactor reports whether count items placed in 1<<B buckets is over loadFactor.
+func overLoadFactor(count int64, B uint8) bool {
+ // TODO: rewrite to use integer math and comparison?
+ return count >= bucketCnt && float32(count) >= loadFactor*float32((uintptr(1)<<B))
+}
+
+// tooManyOverflowBuckets reports whether noverflow buckets is too many for a map with 1<<B buckets.
+// Note that most of these overflow buckets must be in sparse use;
+// if use was dense, then we'd have already triggered regular map growth.
+func tooManyOverflowBuckets(noverflow uint16, B uint8) bool {
+ // If the threshold is too low, we do extraneous work.
+ // If the threshold is too high, maps that grow and shrink can hold on to lots of unused memory.
+ // "too many" means (approximately) as many overflow buckets as regular buckets.
+ // See incrnoverflow for more details.
+ if B < 16 {
+ return noverflow >= uint16(1)<<B
+ }
+ return noverflow >= 1<<15
+}
+
+// growing reports whether h is growing. The growth may be to the same size or bigger.
+func (h *hmap) growing() bool {
+ return h.oldbuckets != nil
+}
+
+// sameSizeGrow reports whether the current growth is to a map of the same size.
+func (h *hmap) sameSizeGrow() bool {
+ return h.flags&sameSizeGrow != 0
+}
+
+// noldbuckets calculates the number of buckets prior to the current map growth.
+func (h *hmap) noldbuckets() uintptr {
+ oldB := h.B
+ if !h.sameSizeGrow() {
+ oldB--
+ }
+ return uintptr(1) << oldB
+}
+
+// oldbucketmask provides a mask that can be applied to calculate n % noldbuckets().
+func (h *hmap) oldbucketmask() uintptr {
+ return h.noldbuckets() - 1
+}
+func growWork(t *maptype, h *hmap, bucket uintptr) {
// make sure we evacuate the oldbucket corresponding
// to the bucket we're about to use
- evacuate(t, h, bucket&(noldbuckets-1))
+ evacuate(t, h, bucket&h.oldbucketmask())
// evacuate one more oldbucket to make progress on growing
- if h.oldbuckets != nil {
+ if h.growing() {
evacuate(t, h, h.nevacuate)
}
}
func evacuate(t *maptype, h *hmap, oldbucket uintptr) {
b := (*bmap)(add(h.oldbuckets, oldbucket*uintptr(t.bucketsize)))
- newbit := uintptr(1) << (h.B - 1)
+ newbit := h.noldbuckets()
hashfn := t.key.hashfn
equalfn := t.key.equalfn
if !evacuated(b) {
// TODO: reuse overflow buckets instead of using new ones, if there
// is no iterator using the old buckets. (If !oldIterator.)
- x := (*bmap)(add(h.buckets, oldbucket*uintptr(t.bucketsize)))
- y := (*bmap)(add(h.buckets, (oldbucket+newbit)*uintptr(t.bucketsize)))
- xi := 0
- yi := 0
- xk := add(unsafe.Pointer(x), dataOffset)
- yk := add(unsafe.Pointer(y), dataOffset)
- xv := add(xk, bucketCnt*uintptr(t.keysize))
- yv := add(yk, bucketCnt*uintptr(t.keysize))
+ var (
+ x, y *bmap // current low/high buckets in new map
+ xi, yi int // key/val indices into x and y
+ xk, yk unsafe.Pointer // pointers to current x and y key storage
+ xv, yv unsafe.Pointer // pointers to current x and y value storage
+ )
+ x = (*bmap)(add(h.buckets, oldbucket*uintptr(t.bucketsize)))
+ xi = 0
+ xk = add(unsafe.Pointer(x), dataOffset)
+ xv = add(xk, bucketCnt*uintptr(t.keysize))
+ if !h.sameSizeGrow() {
+ // Only calculate y pointers if we're growing bigger.
+ // Otherwise GC can see bad pointers.
+ y = (*bmap)(add(h.buckets, (oldbucket+newbit)*uintptr(t.bucketsize)))
+ yi = 0
+ yk = add(unsafe.Pointer(y), dataOffset)
+ yv = add(yk, bucketCnt*uintptr(t.keysize))
+ }
for ; b != nil; b = b.overflow(t) {
k := add(unsafe.Pointer(b), dataOffset)
v := add(k, bucketCnt*uintptr(t.keysize))
@@ -911,34 +1020,38 @@ func evacuate(t *maptype, h *hmap, oldbucket uintptr) {
if t.indirectkey {
k2 = *((*unsafe.Pointer)(k2))
}
- // Compute hash to make our evacuation decision (whether we need
- // to send this key/value to bucket x or bucket y).
- hash := hashfn(k2, uintptr(h.hash0))
- if h.flags&iterator != 0 {
- if !t.reflexivekey && !equalfn(k2, k2) {
- // If key != key (NaNs), then the hash could be (and probably
- // will be) entirely different from the old hash. Moreover,
- // it isn't reproducible. Reproducibility is required in the
- // presence of iterators, as our evacuation decision must
- // match whatever decision the iterator made.
- // Fortunately, we have the freedom to send these keys either
- // way. Also, tophash is meaningless for these kinds of keys.
- // We let the low bit of tophash drive the evacuation decision.
- // We recompute a new random tophash for the next level so
- // these keys will get evenly distributed across all buckets
- // after multiple grows.
- if (top & 1) != 0 {
- hash |= newbit
- } else {
- hash &^= newbit
- }
- top = uint8(hash >> (sys.PtrSize*8 - 8))
- if top < minTopHash {
- top += minTopHash
+ useX := true
+ if !h.sameSizeGrow() {
+ // Compute hash to make our evacuation decision (whether we need
+ // to send this key/value to bucket x or bucket y).
+ hash := hashfn(k2, uintptr(h.hash0))
+ if h.flags&iterator != 0 {
+ if !t.reflexivekey && !equalfn(k2, k2) {
+ // If key != key (NaNs), then the hash could be (and probably
+ // will be) entirely different from the old hash. Moreover,
+ // it isn't reproducible. Reproducibility is required in the
+ // presence of iterators, as our evacuation decision must
+ // match whatever decision the iterator made.
+ // Fortunately, we have the freedom to send these keys either
+ // way. Also, tophash is meaningless for these kinds of keys.
+ // We let the low bit of tophash drive the evacuation decision.
+ // We recompute a new random tophash for the next level so
+ // these keys will get evenly distributed across all buckets
+ // after multiple grows.
+ if top&1 != 0 {
+ hash |= newbit
+ } else {
+ hash &^= newbit
+ }
+ top = uint8(hash >> (sys.PtrSize*8 - 8))
+ if top < minTopHash {
+ top += minTopHash
+ }
}
}
+ useX = hash&newbit == 0
}
- if (hash & newbit) == 0 {
+ if useX {
b.tophash[i] = evacuatedX
if xi == bucketCnt {
newx := (*bmap)(newobject(t.bucket))
@@ -992,7 +1105,13 @@ func evacuate(t *maptype, h *hmap, oldbucket uintptr) {
// Unlink the overflow buckets & clear key/value to help GC.
if h.flags&oldIterator == 0 {
b = (*bmap)(add(h.oldbuckets, oldbucket*uintptr(t.bucketsize)))
- memclr(add(unsafe.Pointer(b), dataOffset), uintptr(t.bucketsize)-dataOffset)
+ // Preserve b.tophash because the evacuation
+ // state is maintained there.
+ if t.bucket.kind&kindNoPointers == 0 {
+ memclrHasPointers(add(unsafe.Pointer(b), dataOffset), uintptr(t.bucketsize)-dataOffset)
+ } else {
+ memclrNoHeapPointers(add(unsafe.Pointer(b), dataOffset), uintptr(t.bucketsize)-dataOffset)
+ }
}
}
@@ -1008,6 +1127,7 @@ func evacuate(t *maptype, h *hmap, oldbucket uintptr) {
if h.overflow != nil {
h.overflow[1] = nil
}
+ h.flags &^= sameSizeGrow
}
}
}
@@ -1035,7 +1155,8 @@ func reflect_mapaccess(t *maptype, h *hmap, key unsafe.Pointer) unsafe.Pointer {
//go:linkname reflect_mapassign reflect.mapassign
func reflect_mapassign(t *maptype, h *hmap, key unsafe.Pointer, val unsafe.Pointer) {
- mapassign1(t, h, key, val)
+ p := mapassign(t, h, key)
+ typedmemmove(t.elem, p, val)
}
//go:linkname reflect_mapdelete reflect.mapdelete
generated by cgit v1.1 at 2025-06-06 10:14:52 +0000