467 lines
13 KiB
Go
467 lines
13 KiB
Go
// Copyright 2018 The Go Authors. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style
|
|
// license that can be found in the LICENSE file.
|
|
|
|
package runtime
|
|
|
|
import (
|
|
"runtime/internal/sys"
|
|
"unsafe"
|
|
)
|
|
|
|
// For gccgo, use go:linkname to export compiler-called functions.
|
|
//
|
|
//go:linkname mapaccess1_fast64
|
|
//go:linkname mapaccess2_fast64
|
|
//go:linkname mapassign_fast64
|
|
//go:linkname mapassign_fast64ptr
|
|
//go:linkname mapdelete_fast64
|
|
|
|
func mapaccess1_fast64(t *maptype, h *hmap, key uint64) unsafe.Pointer {
|
|
if raceenabled && h != nil {
|
|
callerpc := getcallerpc()
|
|
racereadpc(unsafe.Pointer(h), callerpc, funcPC(mapaccess1_fast64))
|
|
}
|
|
if h == nil || h.count == 0 {
|
|
return unsafe.Pointer(&zeroVal[0])
|
|
}
|
|
if h.flags&hashWriting != 0 {
|
|
throw("concurrent map read and map write")
|
|
}
|
|
var b *bmap
|
|
if h.B == 0 {
|
|
// One-bucket table. No need to hash.
|
|
b = (*bmap)(h.buckets)
|
|
} else {
|
|
hash := t.key.hashfn(noescape(unsafe.Pointer(&key)), uintptr(h.hash0))
|
|
m := bucketMask(h.B)
|
|
b = (*bmap)(add(h.buckets, (hash&m)*uintptr(t.bucketsize)))
|
|
if c := h.oldbuckets; c != nil {
|
|
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
|
|
}
|
|
}
|
|
}
|
|
for ; b != nil; b = b.overflow(t) {
|
|
for i, k := uintptr(0), b.keys(); i < bucketCnt; i, k = i+1, add(k, 8) {
|
|
if *(*uint64)(k) == key && !isEmpty(b.tophash[i]) {
|
|
return add(unsafe.Pointer(b), dataOffset+bucketCnt*8+i*uintptr(t.elemsize))
|
|
}
|
|
}
|
|
}
|
|
return unsafe.Pointer(&zeroVal[0])
|
|
}
|
|
|
|
func mapaccess2_fast64(t *maptype, h *hmap, key uint64) (unsafe.Pointer, bool) {
|
|
if raceenabled && h != nil {
|
|
callerpc := getcallerpc()
|
|
racereadpc(unsafe.Pointer(h), callerpc, funcPC(mapaccess2_fast64))
|
|
}
|
|
if h == nil || h.count == 0 {
|
|
return unsafe.Pointer(&zeroVal[0]), false
|
|
}
|
|
if h.flags&hashWriting != 0 {
|
|
throw("concurrent map read and map write")
|
|
}
|
|
var b *bmap
|
|
if h.B == 0 {
|
|
// One-bucket table. No need to hash.
|
|
b = (*bmap)(h.buckets)
|
|
} else {
|
|
hash := t.key.hashfn(noescape(unsafe.Pointer(&key)), uintptr(h.hash0))
|
|
m := bucketMask(h.B)
|
|
b = (*bmap)(add(h.buckets, (hash&m)*uintptr(t.bucketsize)))
|
|
if c := h.oldbuckets; c != nil {
|
|
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
|
|
}
|
|
}
|
|
}
|
|
for ; b != nil; b = b.overflow(t) {
|
|
for i, k := uintptr(0), b.keys(); i < bucketCnt; i, k = i+1, add(k, 8) {
|
|
if *(*uint64)(k) == key && !isEmpty(b.tophash[i]) {
|
|
return add(unsafe.Pointer(b), dataOffset+bucketCnt*8+i*uintptr(t.elemsize)), true
|
|
}
|
|
}
|
|
}
|
|
return unsafe.Pointer(&zeroVal[0]), false
|
|
}
|
|
|
|
func mapassign_fast64(t *maptype, h *hmap, key uint64) unsafe.Pointer {
|
|
if h == nil {
|
|
panic(plainError("assignment to entry in nil map"))
|
|
}
|
|
if raceenabled {
|
|
callerpc := getcallerpc()
|
|
racewritepc(unsafe.Pointer(h), callerpc, funcPC(mapassign_fast64))
|
|
}
|
|
if h.flags&hashWriting != 0 {
|
|
throw("concurrent map writes")
|
|
}
|
|
hash := t.key.hashfn(noescape(unsafe.Pointer(&key)), uintptr(h.hash0))
|
|
|
|
// Set hashWriting after calling alg.hash for consistency with mapassign.
|
|
h.flags ^= hashWriting
|
|
|
|
if h.buckets == nil {
|
|
h.buckets = newobject(t.bucket) // newarray(t.bucket, 1)
|
|
}
|
|
|
|
again:
|
|
bucket := hash & bucketMask(h.B)
|
|
if h.growing() {
|
|
growWork_fast64(t, h, bucket)
|
|
}
|
|
b := (*bmap)(unsafe.Pointer(uintptr(h.buckets) + bucket*uintptr(t.bucketsize)))
|
|
|
|
var insertb *bmap
|
|
var inserti uintptr
|
|
var insertk unsafe.Pointer
|
|
|
|
bucketloop:
|
|
for {
|
|
for i := uintptr(0); i < bucketCnt; i++ {
|
|
if isEmpty(b.tophash[i]) {
|
|
if insertb == nil {
|
|
insertb = b
|
|
inserti = i
|
|
}
|
|
if b.tophash[i] == emptyRest {
|
|
break bucketloop
|
|
}
|
|
continue
|
|
}
|
|
k := *((*uint64)(add(unsafe.Pointer(b), dataOffset+i*8)))
|
|
if k != key {
|
|
continue
|
|
}
|
|
insertb = b
|
|
inserti = i
|
|
goto done
|
|
}
|
|
ovf := b.overflow(t)
|
|
if ovf == nil {
|
|
break
|
|
}
|
|
b = ovf
|
|
}
|
|
|
|
// 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(h.count+1, h.B) || tooManyOverflowBuckets(h.noverflow, h.B)) {
|
|
hashGrow(t, h)
|
|
goto again // Growing the table invalidates everything, so try again
|
|
}
|
|
|
|
if insertb == nil {
|
|
// all current buckets are full, allocate a new one.
|
|
insertb = h.newoverflow(t, b)
|
|
inserti = 0 // not necessary, but avoids needlessly spilling inserti
|
|
}
|
|
insertb.tophash[inserti&(bucketCnt-1)] = tophash(hash) // mask inserti to avoid bounds checks
|
|
|
|
insertk = add(unsafe.Pointer(insertb), dataOffset+inserti*8)
|
|
// store new key at insert position
|
|
*(*uint64)(insertk) = key
|
|
|
|
h.count++
|
|
|
|
done:
|
|
elem := add(unsafe.Pointer(insertb), dataOffset+bucketCnt*8+inserti*uintptr(t.elemsize))
|
|
if h.flags&hashWriting == 0 {
|
|
throw("concurrent map writes")
|
|
}
|
|
h.flags &^= hashWriting
|
|
return elem
|
|
}
|
|
|
|
func mapassign_fast64ptr(t *maptype, h *hmap, key unsafe.Pointer) unsafe.Pointer {
|
|
if h == nil {
|
|
panic(plainError("assignment to entry in nil map"))
|
|
}
|
|
if raceenabled {
|
|
callerpc := getcallerpc()
|
|
racewritepc(unsafe.Pointer(h), callerpc, funcPC(mapassign_fast64))
|
|
}
|
|
if h.flags&hashWriting != 0 {
|
|
throw("concurrent map writes")
|
|
}
|
|
hash := t.key.hashfn(noescape(unsafe.Pointer(&key)), uintptr(h.hash0))
|
|
|
|
// Set hashWriting after calling alg.hash for consistency with mapassign.
|
|
h.flags ^= hashWriting
|
|
|
|
if h.buckets == nil {
|
|
h.buckets = newobject(t.bucket) // newarray(t.bucket, 1)
|
|
}
|
|
|
|
again:
|
|
bucket := hash & bucketMask(h.B)
|
|
if h.growing() {
|
|
growWork_fast64(t, h, bucket)
|
|
}
|
|
b := (*bmap)(unsafe.Pointer(uintptr(h.buckets) + bucket*uintptr(t.bucketsize)))
|
|
|
|
var insertb *bmap
|
|
var inserti uintptr
|
|
var insertk unsafe.Pointer
|
|
|
|
bucketloop:
|
|
for {
|
|
for i := uintptr(0); i < bucketCnt; i++ {
|
|
if isEmpty(b.tophash[i]) {
|
|
if insertb == nil {
|
|
insertb = b
|
|
inserti = i
|
|
}
|
|
if b.tophash[i] == emptyRest {
|
|
break bucketloop
|
|
}
|
|
continue
|
|
}
|
|
k := *((*unsafe.Pointer)(add(unsafe.Pointer(b), dataOffset+i*8)))
|
|
if k != key {
|
|
continue
|
|
}
|
|
insertb = b
|
|
inserti = i
|
|
goto done
|
|
}
|
|
ovf := b.overflow(t)
|
|
if ovf == nil {
|
|
break
|
|
}
|
|
b = ovf
|
|
}
|
|
|
|
// 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(h.count+1, h.B) || tooManyOverflowBuckets(h.noverflow, h.B)) {
|
|
hashGrow(t, h)
|
|
goto again // Growing the table invalidates everything, so try again
|
|
}
|
|
|
|
if insertb == nil {
|
|
// all current buckets are full, allocate a new one.
|
|
insertb = h.newoverflow(t, b)
|
|
inserti = 0 // not necessary, but avoids needlessly spilling inserti
|
|
}
|
|
insertb.tophash[inserti&(bucketCnt-1)] = tophash(hash) // mask inserti to avoid bounds checks
|
|
|
|
insertk = add(unsafe.Pointer(insertb), dataOffset+inserti*8)
|
|
// store new key at insert position
|
|
*(*unsafe.Pointer)(insertk) = key
|
|
|
|
h.count++
|
|
|
|
done:
|
|
elem := add(unsafe.Pointer(insertb), dataOffset+bucketCnt*8+inserti*uintptr(t.elemsize))
|
|
if h.flags&hashWriting == 0 {
|
|
throw("concurrent map writes")
|
|
}
|
|
h.flags &^= hashWriting
|
|
return elem
|
|
}
|
|
|
|
func mapdelete_fast64(t *maptype, h *hmap, key uint64) {
|
|
if raceenabled && h != nil {
|
|
callerpc := getcallerpc()
|
|
racewritepc(unsafe.Pointer(h), callerpc, funcPC(mapdelete_fast64))
|
|
}
|
|
if h == nil || h.count == 0 {
|
|
return
|
|
}
|
|
if h.flags&hashWriting != 0 {
|
|
throw("concurrent map writes")
|
|
}
|
|
|
|
hash := t.key.hashfn(noescape(unsafe.Pointer(&key)), uintptr(h.hash0))
|
|
|
|
// Set hashWriting after calling alg.hash for consistency with mapdelete
|
|
h.flags ^= hashWriting
|
|
|
|
bucket := hash & bucketMask(h.B)
|
|
if h.growing() {
|
|
growWork_fast64(t, h, bucket)
|
|
}
|
|
b := (*bmap)(add(h.buckets, bucket*uintptr(t.bucketsize)))
|
|
bOrig := b
|
|
search:
|
|
for ; b != nil; b = b.overflow(t) {
|
|
for i, k := uintptr(0), b.keys(); i < bucketCnt; i, k = i+1, add(k, 8) {
|
|
if key != *(*uint64)(k) || isEmpty(b.tophash[i]) {
|
|
continue
|
|
}
|
|
// Only clear key if there are pointers in it.
|
|
if t.key.ptrdata != 0 {
|
|
memclrHasPointers(k, t.key.size)
|
|
}
|
|
e := add(unsafe.Pointer(b), dataOffset+bucketCnt*8+i*uintptr(t.elemsize))
|
|
if t.elem.ptrdata != 0 {
|
|
memclrHasPointers(e, t.elem.size)
|
|
} else {
|
|
memclrNoHeapPointers(e, t.elem.size)
|
|
}
|
|
b.tophash[i] = emptyOne
|
|
// If the bucket now ends in a bunch of emptyOne states,
|
|
// change those to emptyRest states.
|
|
if i == bucketCnt-1 {
|
|
if b.overflow(t) != nil && b.overflow(t).tophash[0] != emptyRest {
|
|
goto notLast
|
|
}
|
|
} else {
|
|
if b.tophash[i+1] != emptyRest {
|
|
goto notLast
|
|
}
|
|
}
|
|
for {
|
|
b.tophash[i] = emptyRest
|
|
if i == 0 {
|
|
if b == bOrig {
|
|
break // beginning of initial bucket, we're done.
|
|
}
|
|
// Find previous bucket, continue at its last entry.
|
|
c := b
|
|
for b = bOrig; b.overflow(t) != c; b = b.overflow(t) {
|
|
}
|
|
i = bucketCnt - 1
|
|
} else {
|
|
i--
|
|
}
|
|
if b.tophash[i] != emptyOne {
|
|
break
|
|
}
|
|
}
|
|
notLast:
|
|
h.count--
|
|
break search
|
|
}
|
|
}
|
|
|
|
if h.flags&hashWriting == 0 {
|
|
throw("concurrent map writes")
|
|
}
|
|
h.flags &^= hashWriting
|
|
}
|
|
|
|
func growWork_fast64(t *maptype, h *hmap, bucket uintptr) {
|
|
// make sure we evacuate the oldbucket corresponding
|
|
// to the bucket we're about to use
|
|
evacuate_fast64(t, h, bucket&h.oldbucketmask())
|
|
|
|
// evacuate one more oldbucket to make progress on growing
|
|
if h.growing() {
|
|
evacuate_fast64(t, h, h.nevacuate)
|
|
}
|
|
}
|
|
|
|
func evacuate_fast64(t *maptype, h *hmap, oldbucket uintptr) {
|
|
b := (*bmap)(add(h.oldbuckets, oldbucket*uintptr(t.bucketsize)))
|
|
newbit := h.noldbuckets()
|
|
if !evacuated(b) {
|
|
// TODO: reuse overflow buckets instead of using new ones, if there
|
|
// is no iterator using the old buckets. (If !oldIterator.)
|
|
|
|
// xy contains the x and y (low and high) evacuation destinations.
|
|
var xy [2]evacDst
|
|
x := &xy[0]
|
|
x.b = (*bmap)(add(h.buckets, oldbucket*uintptr(t.bucketsize)))
|
|
x.k = add(unsafe.Pointer(x.b), dataOffset)
|
|
x.e = add(x.k, bucketCnt*8)
|
|
|
|
if !h.sameSizeGrow() {
|
|
// Only calculate y pointers if we're growing bigger.
|
|
// Otherwise GC can see bad pointers.
|
|
y := &xy[1]
|
|
y.b = (*bmap)(add(h.buckets, (oldbucket+newbit)*uintptr(t.bucketsize)))
|
|
y.k = add(unsafe.Pointer(y.b), dataOffset)
|
|
y.e = add(y.k, bucketCnt*8)
|
|
}
|
|
|
|
for ; b != nil; b = b.overflow(t) {
|
|
k := add(unsafe.Pointer(b), dataOffset)
|
|
e := add(k, bucketCnt*8)
|
|
for i := 0; i < bucketCnt; i, k, e = i+1, add(k, 8), add(e, uintptr(t.elemsize)) {
|
|
top := b.tophash[i]
|
|
if isEmpty(top) {
|
|
b.tophash[i] = evacuatedEmpty
|
|
continue
|
|
}
|
|
if top < minTopHash {
|
|
throw("bad map state")
|
|
}
|
|
var useY uint8
|
|
if !h.sameSizeGrow() {
|
|
// Compute hash to make our evacuation decision (whether we need
|
|
// to send this key/elem to bucket x or bucket y).
|
|
hash := t.key.hashfn(k, uintptr(h.hash0))
|
|
if hash&newbit != 0 {
|
|
useY = 1
|
|
}
|
|
}
|
|
|
|
b.tophash[i] = evacuatedX + useY // evacuatedX + 1 == evacuatedY, enforced in makemap
|
|
dst := &xy[useY] // evacuation destination
|
|
|
|
if dst.i == bucketCnt {
|
|
dst.b = h.newoverflow(t, dst.b)
|
|
dst.i = 0
|
|
dst.k = add(unsafe.Pointer(dst.b), dataOffset)
|
|
dst.e = add(dst.k, bucketCnt*8)
|
|
}
|
|
dst.b.tophash[dst.i&(bucketCnt-1)] = top // mask dst.i as an optimization, to avoid a bounds check
|
|
|
|
// Copy key.
|
|
if t.key.ptrdata != 0 && writeBarrier.enabled {
|
|
if sys.PtrSize == 8 {
|
|
// Write with a write barrier.
|
|
*(*unsafe.Pointer)(dst.k) = *(*unsafe.Pointer)(k)
|
|
} else {
|
|
// There are three ways to squeeze at least one 32 bit pointer into 64 bits.
|
|
// Give up and call typedmemmove.
|
|
typedmemmove(t.key, dst.k, k)
|
|
}
|
|
} else {
|
|
*(*uint64)(dst.k) = *(*uint64)(k)
|
|
}
|
|
|
|
typedmemmove(t.elem, dst.e, e)
|
|
dst.i++
|
|
// These updates might push these pointers past the end of the
|
|
// key or elem arrays. That's ok, as we have the overflow pointer
|
|
// at the end of the bucket to protect against pointing past the
|
|
// end of the bucket.
|
|
dst.k = add(dst.k, 8)
|
|
dst.e = add(dst.e, uintptr(t.elemsize))
|
|
}
|
|
}
|
|
// Unlink the overflow buckets & clear key/elem to help GC.
|
|
if h.flags&oldIterator == 0 && t.bucket.ptrdata != 0 {
|
|
b := add(h.oldbuckets, oldbucket*uintptr(t.bucketsize))
|
|
// Preserve b.tophash because the evacuation
|
|
// state is maintained there.
|
|
ptr := add(b, dataOffset)
|
|
n := uintptr(t.bucketsize) - dataOffset
|
|
memclrHasPointers(ptr, n)
|
|
}
|
|
}
|
|
|
|
if oldbucket == h.nevacuate {
|
|
advanceEvacuationMark(h, t, newbit)
|
|
}
|
|
}
|