516 lines
13 KiB
Go
516 lines
13 KiB
Go
// Copyright 2014 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 (
|
|
"internal/cpu"
|
|
"internal/goarch"
|
|
"unsafe"
|
|
)
|
|
|
|
// For gccgo, use go:linkname to export compiler-called functions.
|
|
//
|
|
//go:linkname memhash0
|
|
//go:linkname memhash8
|
|
//go:linkname memhash16
|
|
//go:linkname memhash32
|
|
//go:linkname memhash64
|
|
//go:linkname memhash128
|
|
//go:linkname strhash
|
|
//go:linkname f32hash
|
|
//go:linkname f64hash
|
|
//go:linkname c64hash
|
|
//go:linkname c128hash
|
|
//go:linkname interhash
|
|
//go:linkname nilinterhash
|
|
//go:linkname memequal0
|
|
//go:linkname memequal8
|
|
//go:linkname memequal16
|
|
//go:linkname memequal32
|
|
//go:linkname memequal64
|
|
//go:linkname memequal128
|
|
//go:linkname strequal
|
|
//go:linkname f32equal
|
|
//go:linkname f64equal
|
|
//go:linkname c64equal
|
|
//go:linkname c128equal
|
|
//go:linkname interequal
|
|
//go:linkname nilinterequal
|
|
//go:linkname efaceeq
|
|
//go:linkname ifaceeq
|
|
//go:linkname ifacevaleq
|
|
//go:linkname ifaceefaceeq
|
|
//go:linkname efacevaleq
|
|
//go:linkname cmpstring
|
|
//
|
|
// Temporary to be called from C code.
|
|
//go:linkname alginit
|
|
|
|
const (
|
|
c0 = uintptr((8-goarch.PtrSize)/4*2860486313 + (goarch.PtrSize-4)/4*33054211828000289)
|
|
c1 = uintptr((8-goarch.PtrSize)/4*3267000013 + (goarch.PtrSize-4)/4*23344194077549503)
|
|
)
|
|
|
|
func memhash0(p unsafe.Pointer, h uintptr) uintptr {
|
|
return h
|
|
}
|
|
|
|
func memhash8(p unsafe.Pointer, h uintptr) uintptr {
|
|
return memhash(p, h, 1)
|
|
}
|
|
|
|
func memhash16(p unsafe.Pointer, h uintptr) uintptr {
|
|
return memhash(p, h, 2)
|
|
}
|
|
|
|
func memhash128(p unsafe.Pointer, h uintptr) uintptr {
|
|
return memhash(p, h, 16)
|
|
}
|
|
|
|
// runtime variable to check if the processor we're running on
|
|
// actually supports the instructions used by the AES-based
|
|
// hash implementation.
|
|
var useAeshash bool
|
|
|
|
// in C code
|
|
func aeshashbody(p unsafe.Pointer, h, s uintptr, sched []byte) uintptr
|
|
|
|
func aeshash(p unsafe.Pointer, h, s uintptr) uintptr {
|
|
return aeshashbody(p, h, s, aeskeysched[:])
|
|
}
|
|
|
|
func aeshashstr(p unsafe.Pointer, h uintptr) uintptr {
|
|
ps := (*stringStruct)(p)
|
|
return aeshashbody(unsafe.Pointer(ps.str), h, uintptr(ps.len), aeskeysched[:])
|
|
}
|
|
|
|
func strhash(a unsafe.Pointer, h uintptr) uintptr {
|
|
x := (*stringStruct)(a)
|
|
return memhash(x.str, h, uintptr(x.len))
|
|
}
|
|
|
|
// NOTE: Because NaN != NaN, a map can contain any
|
|
// number of (mostly useless) entries keyed with NaNs.
|
|
// To avoid long hash chains, we assign a random number
|
|
// as the hash value for a NaN.
|
|
|
|
func f32hash(p unsafe.Pointer, h uintptr) uintptr {
|
|
f := *(*float32)(p)
|
|
switch {
|
|
case f == 0:
|
|
return c1 * (c0 ^ h) // +0, -0
|
|
case f != f:
|
|
return c1 * (c0 ^ h ^ uintptr(fastrand())) // any kind of NaN
|
|
default:
|
|
return memhash(p, h, 4)
|
|
}
|
|
}
|
|
|
|
func f64hash(p unsafe.Pointer, h uintptr) uintptr {
|
|
f := *(*float64)(p)
|
|
switch {
|
|
case f == 0:
|
|
return c1 * (c0 ^ h) // +0, -0
|
|
case f != f:
|
|
return c1 * (c0 ^ h ^ uintptr(fastrand())) // any kind of NaN
|
|
default:
|
|
return memhash(p, h, 8)
|
|
}
|
|
}
|
|
|
|
func c64hash(p unsafe.Pointer, h uintptr) uintptr {
|
|
x := (*[2]float32)(p)
|
|
return f32hash(unsafe.Pointer(&x[1]), f32hash(unsafe.Pointer(&x[0]), h))
|
|
}
|
|
|
|
func c128hash(p unsafe.Pointer, h uintptr) uintptr {
|
|
x := (*[2]float64)(p)
|
|
return f64hash(unsafe.Pointer(&x[1]), f64hash(unsafe.Pointer(&x[0]), h))
|
|
}
|
|
|
|
func interhash(p unsafe.Pointer, h uintptr) uintptr {
|
|
a := (*iface)(p)
|
|
tab := a.tab
|
|
if tab == nil {
|
|
return h
|
|
}
|
|
t := *(**_type)(tab)
|
|
if t.equal == nil {
|
|
// Check hashability here. We could do this check inside
|
|
// typehash, but we want to report the topmost type in
|
|
// the error text (e.g. in a struct with a field of slice type
|
|
// we want to report the struct, not the slice).
|
|
panic(errorString("hash of unhashable type " + t.string()))
|
|
}
|
|
if isDirectIface(t) {
|
|
return c1 * typehash(t, unsafe.Pointer(&a.data), h^c0)
|
|
} else {
|
|
return c1 * typehash(t, a.data, h^c0)
|
|
}
|
|
}
|
|
|
|
func nilinterhash(p unsafe.Pointer, h uintptr) uintptr {
|
|
a := (*eface)(p)
|
|
t := a._type
|
|
if t == nil {
|
|
return h
|
|
}
|
|
if t.equal == nil {
|
|
// See comment in interhash above.
|
|
panic(errorString("hash of unhashable type " + t.string()))
|
|
}
|
|
if isDirectIface(t) {
|
|
return c1 * typehash(t, unsafe.Pointer(&a.data), h^c0)
|
|
} else {
|
|
return c1 * typehash(t, a.data, h^c0)
|
|
}
|
|
}
|
|
|
|
// typehash computes the hash of the object of type t at address p.
|
|
// h is the seed.
|
|
// This function is seldom used. Most maps use for hashing either
|
|
// fixed functions (e.g. f32hash) or compiler-generated functions
|
|
// (e.g. for a type like struct { x, y string }). This implementation
|
|
// is slower but more general and is used for hashing interface types
|
|
// (called from interhash or nilinterhash, above) or for hashing in
|
|
// maps generated by reflect.MapOf (reflect_typehash, below).
|
|
// Note: this function must match the compiler generated
|
|
// functions exactly. See issue 37716.
|
|
func typehash(t *_type, p unsafe.Pointer, h uintptr) uintptr {
|
|
if t.tflag&tflagRegularMemory != 0 {
|
|
// Handle ptr sizes specially, see issue 37086.
|
|
switch t.size {
|
|
case 4:
|
|
return memhash32(p, h)
|
|
case 8:
|
|
return memhash64(p, h)
|
|
default:
|
|
return memhash(p, h, t.size)
|
|
}
|
|
}
|
|
switch t.kind & kindMask {
|
|
case kindFloat32:
|
|
return f32hash(p, h)
|
|
case kindFloat64:
|
|
return f64hash(p, h)
|
|
case kindComplex64:
|
|
return c64hash(p, h)
|
|
case kindComplex128:
|
|
return c128hash(p, h)
|
|
case kindString:
|
|
return strhash(p, h)
|
|
case kindInterface:
|
|
i := (*interfacetype)(unsafe.Pointer(t))
|
|
if len(i.methods) == 0 {
|
|
return nilinterhash(p, h)
|
|
}
|
|
return interhash(p, h)
|
|
case kindArray:
|
|
a := (*arraytype)(unsafe.Pointer(t))
|
|
for i := uintptr(0); i < a.len; i++ {
|
|
h = typehash(a.elem, add(p, i*a.elem.size), h)
|
|
}
|
|
return h
|
|
case kindStruct:
|
|
s := (*structtype)(unsafe.Pointer(t))
|
|
for _, f := range s.fields {
|
|
if f.name != nil && *f.name == "_" {
|
|
continue
|
|
}
|
|
h = typehash(f.typ, add(p, f.offset()), h)
|
|
}
|
|
return h
|
|
default:
|
|
// Should never happen, as typehash should only be called
|
|
// with comparable types.
|
|
panic(errorString("hash of unhashable type " + t.string()))
|
|
}
|
|
}
|
|
|
|
//go:linkname reflect_typehash reflect.typehash
|
|
func reflect_typehash(t *_type, p unsafe.Pointer, h uintptr) uintptr {
|
|
return typehash(t, p, h)
|
|
}
|
|
|
|
func memequal0(p, q unsafe.Pointer) bool {
|
|
return true
|
|
}
|
|
func memequal8(p, q unsafe.Pointer) bool {
|
|
return *(*int8)(p) == *(*int8)(q)
|
|
}
|
|
func memequal16(p, q unsafe.Pointer) bool {
|
|
return *(*int16)(p) == *(*int16)(q)
|
|
}
|
|
func memequal32(p, q unsafe.Pointer) bool {
|
|
return *(*int32)(p) == *(*int32)(q)
|
|
}
|
|
func memequal64(p, q unsafe.Pointer) bool {
|
|
return *(*int64)(p) == *(*int64)(q)
|
|
}
|
|
func memequal128(p, q unsafe.Pointer) bool {
|
|
return *(*[2]int64)(p) == *(*[2]int64)(q)
|
|
}
|
|
func f32equal(p, q unsafe.Pointer) bool {
|
|
return *(*float32)(p) == *(*float32)(q)
|
|
}
|
|
func f64equal(p, q unsafe.Pointer) bool {
|
|
return *(*float64)(p) == *(*float64)(q)
|
|
}
|
|
func c64equal(p, q unsafe.Pointer) bool {
|
|
return *(*complex64)(p) == *(*complex64)(q)
|
|
}
|
|
func c128equal(p, q unsafe.Pointer) bool {
|
|
return *(*complex128)(p) == *(*complex128)(q)
|
|
}
|
|
func strequal(p, q unsafe.Pointer) bool {
|
|
return *(*string)(p) == *(*string)(q)
|
|
}
|
|
func interequal(p, q unsafe.Pointer) bool {
|
|
return ifaceeq(*(*iface)(p), *(*iface)(q))
|
|
}
|
|
func nilinterequal(p, q unsafe.Pointer) bool {
|
|
return efaceeq(*(*eface)(p), *(*eface)(q))
|
|
}
|
|
func efaceeq(x, y eface) bool {
|
|
t := x._type
|
|
if !eqtype(t, y._type) {
|
|
return false
|
|
}
|
|
if t == nil {
|
|
return true
|
|
}
|
|
eq := t.equal
|
|
if eq == nil {
|
|
panic(errorString("comparing uncomparable type " + t.string()))
|
|
}
|
|
if isDirectIface(t) {
|
|
return x.data == y.data
|
|
}
|
|
return eq(x.data, y.data)
|
|
}
|
|
|
|
func ifaceeq(x, y iface) bool {
|
|
xtab := x.tab
|
|
if xtab == nil && y.tab == nil {
|
|
return true
|
|
}
|
|
if xtab == nil || y.tab == nil {
|
|
return false
|
|
}
|
|
t := *(**_type)(xtab)
|
|
if !eqtype(t, *(**_type)(y.tab)) {
|
|
return false
|
|
}
|
|
eq := t.equal
|
|
if eq == nil {
|
|
panic(errorString("comparing uncomparable type " + t.string()))
|
|
}
|
|
if isDirectIface(t) {
|
|
// Direct interface types are ptr, chan, map, func, and single-element structs/arrays thereof.
|
|
// Maps and funcs are not comparable, so they can't reach here.
|
|
// Ptrs, chans, and single-element items can be compared directly using ==.
|
|
return x.data == y.data
|
|
}
|
|
return eq(x.data, y.data)
|
|
}
|
|
|
|
func ifacevaleq(x iface, t *_type, p unsafe.Pointer) bool {
|
|
if x.tab == nil {
|
|
return false
|
|
}
|
|
xt := *(**_type)(x.tab)
|
|
if !eqtype(xt, t) {
|
|
return false
|
|
}
|
|
eq := t.equal
|
|
if eq == nil {
|
|
panic(errorString("comparing uncomparable type " + t.string()))
|
|
}
|
|
if isDirectIface(t) {
|
|
return x.data == p
|
|
}
|
|
return eq(x.data, p)
|
|
}
|
|
|
|
func ifaceefaceeq(x iface, y eface) bool {
|
|
if x.tab == nil && y._type == nil {
|
|
return true
|
|
}
|
|
if x.tab == nil || y._type == nil {
|
|
return false
|
|
}
|
|
xt := *(**_type)(x.tab)
|
|
if !eqtype(xt, y._type) {
|
|
return false
|
|
}
|
|
eq := xt.equal
|
|
if eq == nil {
|
|
panic(errorString("comparing uncomparable type " + xt.string()))
|
|
}
|
|
if isDirectIface(xt) {
|
|
return x.data == y.data
|
|
}
|
|
return eq(x.data, y.data)
|
|
}
|
|
|
|
func efacevaleq(x eface, t *_type, p unsafe.Pointer) bool {
|
|
if x._type == nil {
|
|
return false
|
|
}
|
|
if !eqtype(x._type, t) {
|
|
return false
|
|
}
|
|
eq := t.equal
|
|
if eq == nil {
|
|
panic(errorString("comparing uncomparable type " + t.string()))
|
|
}
|
|
if isDirectIface(t) {
|
|
// See comment in efaceeq.
|
|
return x.data == p
|
|
}
|
|
return eq(x.data, p)
|
|
}
|
|
|
|
func cmpstring(x, y string) int {
|
|
a := stringStructOf(&x)
|
|
b := stringStructOf(&y)
|
|
l := a.len
|
|
if l > b.len {
|
|
l = b.len
|
|
}
|
|
i := memcmp(unsafe.Pointer(a.str), unsafe.Pointer(b.str), uintptr(l))
|
|
if i != 0 {
|
|
return int(i)
|
|
}
|
|
if a.len < b.len {
|
|
return -1
|
|
} else if a.len > b.len {
|
|
return 1
|
|
}
|
|
return 0
|
|
}
|
|
|
|
// For the unsafe.Pointer type descriptor in libgo/runtime/go-unsafe-pointer.c.
|
|
|
|
func pointerhash(p unsafe.Pointer, h uintptr) uintptr {
|
|
return memhash(p, h, unsafe.Sizeof(unsafe.Pointer))
|
|
}
|
|
|
|
func pointerequal(p, q unsafe.Pointer) bool {
|
|
return *(*unsafe.Pointer)(p) == *(*unsafe.Pointer)(q)
|
|
}
|
|
|
|
// Force the creation of function descriptors for equality and hash
|
|
// functions. These will be referenced directly by the compiler.
|
|
var _ = memhash
|
|
var _ = memhash0
|
|
var _ = memhash8
|
|
var _ = memhash16
|
|
var _ = memhash32
|
|
var _ = memhash64
|
|
var _ = memhash128
|
|
var _ = strhash
|
|
var _ = f32hash
|
|
var _ = f64hash
|
|
var _ = c64hash
|
|
var _ = c128hash
|
|
var _ = interhash
|
|
var _ = nilinterhash
|
|
var _ = memequal0
|
|
var _ = memequal8
|
|
var _ = memequal16
|
|
var _ = memequal32
|
|
var _ = memequal64
|
|
var _ = memequal128
|
|
var _ = f32equal
|
|
var _ = f64equal
|
|
var _ = c64equal
|
|
var _ = c128equal
|
|
var _ = strequal
|
|
var _ = interequal
|
|
var _ = nilinterequal
|
|
var _ = pointerhash
|
|
var _ = pointerequal
|
|
|
|
// Testing adapters for hash quality tests (see hash_test.go)
|
|
func stringHash(s string, seed uintptr) uintptr {
|
|
return strhash(noescape(unsafe.Pointer(&s)), seed)
|
|
}
|
|
|
|
func bytesHash(b []byte, seed uintptr) uintptr {
|
|
s := (*slice)(unsafe.Pointer(&b))
|
|
return memhash(s.array, seed, uintptr(s.len))
|
|
}
|
|
|
|
func int32Hash(i uint32, seed uintptr) uintptr {
|
|
return memhash32(noescape(unsafe.Pointer(&i)), seed)
|
|
}
|
|
|
|
func int64Hash(i uint64, seed uintptr) uintptr {
|
|
return memhash64(noescape(unsafe.Pointer(&i)), seed)
|
|
}
|
|
|
|
func efaceHash(i any, seed uintptr) uintptr {
|
|
return nilinterhash(noescape(unsafe.Pointer(&i)), seed)
|
|
}
|
|
|
|
func ifaceHash(i interface {
|
|
F()
|
|
}, seed uintptr) uintptr {
|
|
return interhash(noescape(unsafe.Pointer(&i)), seed)
|
|
}
|
|
|
|
const hashRandomBytes = goarch.PtrSize / 4 * 64
|
|
|
|
// used in asm_{386,amd64,arm64}.s to seed the hash function
|
|
var aeskeysched [hashRandomBytes]byte
|
|
|
|
// used in hash{32,64}.go to seed the hash function
|
|
var hashkey [4]uintptr
|
|
|
|
func alginit() {
|
|
// Install AES hash algorithms if the instructions needed are present.
|
|
if (GOARCH == "386" || GOARCH == "amd64") &&
|
|
support_aes &&
|
|
cpu.X86.HasAES && // AESENC
|
|
cpu.X86.HasSSSE3 && // PSHUFB
|
|
cpu.X86.HasSSE41 { // PINSR{D,Q}
|
|
initAlgAES()
|
|
return
|
|
}
|
|
if GOARCH == "arm64" && cpu.ARM64.HasAES {
|
|
initAlgAES()
|
|
return
|
|
}
|
|
getRandomData((*[len(hashkey) * goarch.PtrSize]byte)(unsafe.Pointer(&hashkey))[:])
|
|
hashkey[0] |= 1 // make sure these numbers are odd
|
|
hashkey[1] |= 1
|
|
hashkey[2] |= 1
|
|
hashkey[3] |= 1
|
|
}
|
|
|
|
func initAlgAES() {
|
|
useAeshash = true
|
|
// Initialize with random data so hash collisions will be hard to engineer.
|
|
getRandomData(aeskeysched[:])
|
|
}
|
|
|
|
// Note: These routines perform the read with a native endianness.
|
|
func readUnaligned32(p unsafe.Pointer) uint32 {
|
|
q := (*[4]byte)(p)
|
|
if goarch.BigEndian {
|
|
return uint32(q[3]) | uint32(q[2])<<8 | uint32(q[1])<<16 | uint32(q[0])<<24
|
|
}
|
|
return uint32(q[0]) | uint32(q[1])<<8 | uint32(q[2])<<16 | uint32(q[3])<<24
|
|
}
|
|
|
|
func readUnaligned64(p unsafe.Pointer) uint64 {
|
|
q := (*[8]byte)(p)
|
|
if goarch.BigEndian {
|
|
return uint64(q[7]) | uint64(q[6])<<8 | uint64(q[5])<<16 | uint64(q[4])<<24 |
|
|
uint64(q[3])<<32 | uint64(q[2])<<40 | uint64(q[1])<<48 | uint64(q[0])<<56
|
|
}
|
|
return uint64(q[0]) | uint64(q[1])<<8 | uint64(q[2])<<16 | uint64(q[3])<<24 | uint64(q[4])<<32 | uint64(q[5])<<40 | uint64(q[6])<<48 | uint64(q[7])<<56
|
|
}
|