1 files changed, 0 insertions, 476 deletions
diff --git a/vendor/github.com/tetratelabs/wazero/internal/wasm/memory.go b/vendor/github.com/tetratelabs/wazero/internal/wasm/memory.go
deleted file mode 100644
index 9a1f0c6d1..000000000
--- a/vendor/github.com/tetratelabs/wazero/internal/wasm/memory.go
+++ /dev/null
@@ -1,476 +0,0 @@
-package wasm
-
-import (
-	"container/list"
-	"encoding/binary"
-	"fmt"
-	"math"
-	"reflect"
-	"sync"
-	"sync/atomic"
-	"time"
-	"unsafe"
-
-	"github.com/tetratelabs/wazero/api"
-	"github.com/tetratelabs/wazero/experimental"
-	"github.com/tetratelabs/wazero/internal/internalapi"
-	"github.com/tetratelabs/wazero/internal/wasmruntime"
-)
-
-const (
-	// MemoryPageSize is the unit of memory length in WebAssembly,
-	// and is defined as 2^16 = 65536.
-	// See https://www.w3.org/TR/2019/REC-wasm-core-1-20191205/#memory-instances%E2%91%A0
-	MemoryPageSize = uint32(65536)
-	// MemoryLimitPages is maximum number of pages defined (2^16).
-	// See https://www.w3.org/TR/2019/REC-wasm-core-1-20191205/#grow-mem
-	MemoryLimitPages = uint32(65536)
-	// MemoryPageSizeInBits satisfies the relation: "1 << MemoryPageSizeInBits == MemoryPageSize".
-	MemoryPageSizeInBits = 16
-)
-
-// compile-time check to ensure MemoryInstance implements api.Memory
-var _ api.Memory = &MemoryInstance{}
-
-type waiters struct {
-	mux sync.Mutex
-	l   *list.List
-}
-
-// MemoryInstance represents a memory instance in a store, and implements api.Memory.
-//
-// Note: In WebAssembly 1.0 (20191205), there may be up to one Memory per store, which means the precise memory is always
-// wasm.Store Memories index zero: `store.Memories[0]`
-// See https://www.w3.org/TR/2019/REC-wasm-core-1-20191205/#memory-instances%E2%91%A0.
-type MemoryInstance struct {
-	internalapi.WazeroOnlyType
-
-	Buffer        []byte
-	Min, Cap, Max uint32
-	Shared        bool
-	// definition is known at compile time.
-	definition api.MemoryDefinition
-
-	// Mux is used in interpreter mode to prevent overlapping calls to atomic instructions,
-	// introduced with WebAssembly threads proposal, and in compiler mode to make memory modifications
-	// within Grow non-racy for the Go race detector.
-	Mux sync.Mutex
-
-	// waiters implements atomic wait and notify. It is implemented similarly to golang.org/x/sync/semaphore,
-	// with a fixed weight of 1 and no spurious notifications.
-	waiters sync.Map
-
-	// ownerModuleEngine is the module engine that owns this memory instance.
-	ownerModuleEngine ModuleEngine
-
-	expBuffer experimental.LinearMemory
-}
-
-// NewMemoryInstance creates a new instance based on the parameters in the SectionIDMemory.
-func NewMemoryInstance(memSec *Memory, allocator experimental.MemoryAllocator, moduleEngine ModuleEngine) *MemoryInstance {
-	minBytes := MemoryPagesToBytesNum(memSec.Min)
-	capBytes := MemoryPagesToBytesNum(memSec.Cap)
-	maxBytes := MemoryPagesToBytesNum(memSec.Max)
-
-	var buffer []byte
-	var expBuffer experimental.LinearMemory
-	if allocator != nil {
-		expBuffer = allocator.Allocate(capBytes, maxBytes)
-		buffer = expBuffer.Reallocate(minBytes)
-		_ = buffer[:minBytes] // Bounds check that the minimum was allocated.
-	} else if memSec.IsShared {
-		// Shared memory needs a fixed buffer, so allocate with the maximum size.
-		//
-		// The rationale as to why we can simply use make([]byte) to a fixed buffer is that Go's GC is non-relocating.
-		// That is not a part of Go spec, but is well-known thing in Go community (wazero's compiler heavily relies on it!)
-		// 	* https://github.com/go4org/unsafe-assume-no-moving-gc
-		//
-		// Also, allocating Max here isn't harmful as the Go runtime uses mmap for large allocations, therefore,
-		// the memory buffer allocation here is virtual and doesn't consume physical memory until it's used.
-		// 	* https://github.com/golang/go/blob/8121604559035734c9677d5281bbdac8b1c17a1e/src/runtime/malloc.go#L1059
-		//	* https://github.com/golang/go/blob/8121604559035734c9677d5281bbdac8b1c17a1e/src/runtime/malloc.go#L1165
-		buffer = make([]byte, minBytes, maxBytes)
-	} else {
-		buffer = make([]byte, minBytes, capBytes)
-	}
-	return &MemoryInstance{
-		Buffer:            buffer,
-		Min:               memSec.Min,
-		Cap:               memoryBytesNumToPages(uint64(cap(buffer))),
-		Max:               memSec.Max,
-		Shared:            memSec.IsShared,
-		expBuffer:         expBuffer,
-		ownerModuleEngine: moduleEngine,
-	}
-}
-
-// Definition implements the same method as documented on api.Memory.
-func (m *MemoryInstance) Definition() api.MemoryDefinition {
-	return m.definition
-}
-
-// Size implements the same method as documented on api.Memory.
-func (m *MemoryInstance) Size() uint32 {
-	return uint32(len(m.Buffer))
-}
-
-// ReadByte implements the same method as documented on api.Memory.
-func (m *MemoryInstance) ReadByte(offset uint32) (byte, bool) {
-	if !m.hasSize(offset, 1) {
-		return 0, false
-	}
-	return m.Buffer[offset], true
-}
-
-// ReadUint16Le implements the same method as documented on api.Memory.
-func (m *MemoryInstance) ReadUint16Le(offset uint32) (uint16, bool) {
-	if !m.hasSize(offset, 2) {
-		return 0, false
-	}
-	return binary.LittleEndian.Uint16(m.Buffer[offset : offset+2]), true
-}
-
-// ReadUint32Le implements the same method as documented on api.Memory.
-func (m *MemoryInstance) ReadUint32Le(offset uint32) (uint32, bool) {
-	return m.readUint32Le(offset)
-}
-
-// ReadFloat32Le implements the same method as documented on api.Memory.
-func (m *MemoryInstance) ReadFloat32Le(offset uint32) (float32, bool) {
-	v, ok := m.readUint32Le(offset)
-	if !ok {
-		return 0, false
-	}
-	return math.Float32frombits(v), true
-}
-
-// ReadUint64Le implements the same method as documented on api.Memory.
-func (m *MemoryInstance) ReadUint64Le(offset uint32) (uint64, bool) {
-	return m.readUint64Le(offset)
-}
-
-// ReadFloat64Le implements the same method as documented on api.Memory.
-func (m *MemoryInstance) ReadFloat64Le(offset uint32) (float64, bool) {
-	v, ok := m.readUint64Le(offset)
-	if !ok {
-		return 0, false
-	}
-	return math.Float64frombits(v), true
-}
-
-// Read implements the same method as documented on api.Memory.
-func (m *MemoryInstance) Read(offset, byteCount uint32) ([]byte, bool) {
-	if !m.hasSize(offset, uint64(byteCount)) {
-		return nil, false
-	}
-	return m.Buffer[offset : offset+byteCount : offset+byteCount], true
-}
-
-// WriteByte implements the same method as documented on api.Memory.
-func (m *MemoryInstance) WriteByte(offset uint32, v byte) bool {
-	if !m.hasSize(offset, 1) {
-		return false
-	}
-	m.Buffer[offset] = v
-	return true
-}
-
-// WriteUint16Le implements the same method as documented on api.Memory.
-func (m *MemoryInstance) WriteUint16Le(offset uint32, v uint16) bool {
-	if !m.hasSize(offset, 2) {
-		return false
-	}
-	binary.LittleEndian.PutUint16(m.Buffer[offset:], v)
-	return true
-}
-
-// WriteUint32Le implements the same method as documented on api.Memory.
-func (m *MemoryInstance) WriteUint32Le(offset, v uint32) bool {
-	return m.writeUint32Le(offset, v)
-}
-
-// WriteFloat32Le implements the same method as documented on api.Memory.
-func (m *MemoryInstance) WriteFloat32Le(offset uint32, v float32) bool {
-	return m.writeUint32Le(offset, math.Float32bits(v))
-}
-
-// WriteUint64Le implements the same method as documented on api.Memory.
-func (m *MemoryInstance) WriteUint64Le(offset uint32, v uint64) bool {
-	return m.writeUint64Le(offset, v)
-}
-
-// WriteFloat64Le implements the same method as documented on api.Memory.
-func (m *MemoryInstance) WriteFloat64Le(offset uint32, v float64) bool {
-	return m.writeUint64Le(offset, math.Float64bits(v))
-}
-
-// Write implements the same method as documented on api.Memory.
-func (m *MemoryInstance) Write(offset uint32, val []byte) bool {
-	if !m.hasSize(offset, uint64(len(val))) {
-		return false
-	}
-	copy(m.Buffer[offset:], val)
-	return true
-}
-
-// WriteString implements the same method as documented on api.Memory.
-func (m *MemoryInstance) WriteString(offset uint32, val string) bool {
-	if !m.hasSize(offset, uint64(len(val))) {
-		return false
-	}
-	copy(m.Buffer[offset:], val)
-	return true
-}
-
-// MemoryPagesToBytesNum converts the given pages into the number of bytes contained in these pages.
-func MemoryPagesToBytesNum(pages uint32) (bytesNum uint64) {
-	return uint64(pages) << MemoryPageSizeInBits
-}
-
-// Grow implements the same method as documented on api.Memory.
-func (m *MemoryInstance) Grow(delta uint32) (result uint32, ok bool) {
-	if m.Shared {
-		m.Mux.Lock()
-		defer m.Mux.Unlock()
-	}
-
-	currentPages := m.Pages()
-	if delta == 0 {
-		return currentPages, true
-	}
-
-	newPages := currentPages + delta
-	if newPages > m.Max || int32(delta) < 0 {
-		return 0, false
-	} else if m.expBuffer != nil {
-		buffer := m.expBuffer.Reallocate(MemoryPagesToBytesNum(newPages))
-		if buffer == nil {
-			// Allocator failed to grow.
-			return 0, false
-		}
-		if m.Shared {
-			if unsafe.SliceData(buffer) != unsafe.SliceData(m.Buffer) {
-				panic("shared memory cannot move, this is a bug in the memory allocator")
-			}
-			// We assume grow is called under a guest lock.
-			// But the memory length is accessed elsewhere,
-			// so use atomic to make the new length visible across threads.
-			atomicStoreLengthAndCap(&m.Buffer, uintptr(len(buffer)), uintptr(cap(buffer)))
-			m.Cap = memoryBytesNumToPages(uint64(cap(buffer)))
-		} else {
-			m.Buffer = buffer
-			m.Cap = newPages
-		}
-	} else if newPages > m.Cap { // grow the memory.
-		if m.Shared {
-			panic("shared memory cannot be grown, this is a bug in wazero")
-		}
-		m.Buffer = append(m.Buffer, make([]byte, MemoryPagesToBytesNum(delta))...)
-		m.Cap = newPages
-	} else { // We already have the capacity we need.
-		if m.Shared {
-			// We assume grow is called under a guest lock.
-			// But the memory length is accessed elsewhere,
-			// so use atomic to make the new length visible across threads.
-			atomicStoreLength(&m.Buffer, uintptr(MemoryPagesToBytesNum(newPages)))
-		} else {
-			m.Buffer = m.Buffer[:MemoryPagesToBytesNum(newPages)]
-		}
-	}
-	m.ownerModuleEngine.MemoryGrown()
-	return currentPages, true
-}
-
-// Pages implements the same method as documented on api.Memory.
-func (m *MemoryInstance) Pages() (result uint32) {
-	return memoryBytesNumToPages(uint64(len(m.Buffer)))
-}
-
-// PagesToUnitOfBytes converts the pages to a human-readable form similar to what's specified. e.g. 1 -> "64Ki"
-//
-// See https://www.w3.org/TR/2019/REC-wasm-core-1-20191205/#memory-instances%E2%91%A0
-func PagesToUnitOfBytes(pages uint32) string {
-	k := pages * 64
-	if k < 1024 {
-		return fmt.Sprintf("%d Ki", k)
-	}
-	m := k / 1024
-	if m < 1024 {
-		return fmt.Sprintf("%d Mi", m)
-	}
-	g := m / 1024
-	if g < 1024 {
-		return fmt.Sprintf("%d Gi", g)
-	}
-	return fmt.Sprintf("%d Ti", g/1024)
-}
-
-// Below are raw functions used to implement the api.Memory API:
-
-// Uses atomic write to update the length of a slice.
-func atomicStoreLengthAndCap(slice *[]byte, length uintptr, cap uintptr) {
-	//nolint:staticcheck
-	slicePtr := (*reflect.SliceHeader)(unsafe.Pointer(slice))
-	capPtr := (*uintptr)(unsafe.Pointer(&slicePtr.Cap))
-	atomic.StoreUintptr(capPtr, cap)
-	lenPtr := (*uintptr)(unsafe.Pointer(&slicePtr.Len))
-	atomic.StoreUintptr(lenPtr, length)
-}
-
-// Uses atomic write to update the length of a slice.
-func atomicStoreLength(slice *[]byte, length uintptr) {
-	//nolint:staticcheck
-	slicePtr := (*reflect.SliceHeader)(unsafe.Pointer(slice))
-	lenPtr := (*uintptr)(unsafe.Pointer(&slicePtr.Len))
-	atomic.StoreUintptr(lenPtr, length)
-}
-
-// memoryBytesNumToPages converts the given number of bytes into the number of pages.
-func memoryBytesNumToPages(bytesNum uint64) (pages uint32) {
-	return uint32(bytesNum >> MemoryPageSizeInBits)
-}
-
-// hasSize returns true if Len is sufficient for byteCount at the given offset.
-//
-// Note: This is always fine, because memory can grow, but never shrink.
-func (m *MemoryInstance) hasSize(offset uint32, byteCount uint64) bool {
-	return uint64(offset)+byteCount <= uint64(len(m.Buffer)) // uint64 prevents overflow on add
-}
-
-// readUint32Le implements ReadUint32Le without using a context. This is extracted as both ints and floats are stored in
-// memory as uint32le.
-func (m *MemoryInstance) readUint32Le(offset uint32) (uint32, bool) {
-	if !m.hasSize(offset, 4) {
-		return 0, false
-	}
-	return binary.LittleEndian.Uint32(m.Buffer[offset : offset+4]), true
-}
-
-// readUint64Le implements ReadUint64Le without using a context. This is extracted as both ints and floats are stored in
-// memory as uint64le.
-func (m *MemoryInstance) readUint64Le(offset uint32) (uint64, bool) {
-	if !m.hasSize(offset, 8) {
-		return 0, false
-	}
-	return binary.LittleEndian.Uint64(m.Buffer[offset : offset+8]), true
-}
-
-// writeUint32Le implements WriteUint32Le without using a context. This is extracted as both ints and floats are stored
-// in memory as uint32le.
-func (m *MemoryInstance) writeUint32Le(offset uint32, v uint32) bool {
-	if !m.hasSize(offset, 4) {
-		return false
-	}
-	binary.LittleEndian.PutUint32(m.Buffer[offset:], v)
-	return true
-}
-
-// writeUint64Le implements WriteUint64Le without using a context. This is extracted as both ints and floats are stored
-// in memory as uint64le.
-func (m *MemoryInstance) writeUint64Le(offset uint32, v uint64) bool {
-	if !m.hasSize(offset, 8) {
-		return false
-	}
-	binary.LittleEndian.PutUint64(m.Buffer[offset:], v)
-	return true
-}
-
-// Wait32 suspends the caller until the offset is notified by a different agent.
-func (m *MemoryInstance) Wait32(offset uint32, exp uint32, timeout int64, reader func(mem *MemoryInstance, offset uint32) uint32) uint64 {
-	w := m.getWaiters(offset)
-	w.mux.Lock()
-
-	cur := reader(m, offset)
-	if cur != exp {
-		w.mux.Unlock()
-		return 1
-	}
-
-	return m.wait(w, timeout)
-}
-
-// Wait64 suspends the caller until the offset is notified by a different agent.
-func (m *MemoryInstance) Wait64(offset uint32, exp uint64, timeout int64, reader func(mem *MemoryInstance, offset uint32) uint64) uint64 {
-	w := m.getWaiters(offset)
-	w.mux.Lock()
-
-	cur := reader(m, offset)
-	if cur != exp {
-		w.mux.Unlock()
-		return 1
-	}
-
-	return m.wait(w, timeout)
-}
-
-func (m *MemoryInstance) wait(w *waiters, timeout int64) uint64 {
-	if w.l == nil {
-		w.l = list.New()
-	}
-
-	// The specification requires a trap if the number of existing waiters + 1 == 2^32, so we add a check here.
-	// In practice, it is unlikely the application would ever accumulate such a large number of waiters as it
-	// indicates several GB of RAM used just for the list of waiters.
-	// https://github.com/WebAssembly/threads/blob/main/proposals/threads/Overview.md#wait
-	if uint64(w.l.Len()+1) == 1<<32 {
-		w.mux.Unlock()
-		panic(wasmruntime.ErrRuntimeTooManyWaiters)
-	}
-
-	ready := make(chan struct{})
-	elem := w.l.PushBack(ready)
-	w.mux.Unlock()
-
-	if timeout < 0 {
-		<-ready
-		return 0
-	} else {
-		select {
-		case <-ready:
-			return 0
-		case <-time.After(time.Duration(timeout)):
-			// While we could see if the channel completed by now and ignore the timeout, similar to x/sync/semaphore,
-			// the Wasm spec doesn't specify this behavior, so we keep things simple by prioritizing the timeout.
-			w.mux.Lock()
-			w.l.Remove(elem)
-			w.mux.Unlock()
-			return 2
-		}
-	}
-}
-
-func (m *MemoryInstance) getWaiters(offset uint32) *waiters {
-	wAny, ok := m.waiters.Load(offset)
-	if !ok {
-		// The first time an address is waited on, simultaneous waits will cause extra allocations.
-		// Further operations will be loaded above, which is also the general pattern of usage with
-		// mutexes.
-		wAny, _ = m.waiters.LoadOrStore(offset, &waiters{})
-	}
-
-	return wAny.(*waiters)
-}
-
-// Notify wakes up at most count waiters at the given offset.
-func (m *MemoryInstance) Notify(offset uint32, count uint32) uint32 {
-	wAny, ok := m.waiters.Load(offset)
-	if !ok {
-		return 0
-	}
-	w := wAny.(*waiters)
-
-	w.mux.Lock()
-	defer w.mux.Unlock()
-	if w.l == nil {
-		return 0
-	}
-
-	res := uint32(0)
-	for num := w.l.Len(); num > 0 && res < count; num = w.l.Len() {
-		w := w.l.Remove(w.l.Front()).(chan struct{})
-		close(w)
-		res++
-	}
-
-	return res
-}