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714 lines (598 loc) · 22.5 KB
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/** \file
\brief Custom Memory Allocator for Packet Data
\copyright Copyright (c) 2017-2018 Christopher A. Taylor. All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
* Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following disclaimer in the documentation
and/or other materials provided with the distribution.
* Neither the name of PacketAllocator nor the names of its contributors may be
used to endorse or promote products derived from this software without
specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE.
*/
#include "PacketAllocator.h"
#include <cstring> // memcpy
#include <cstdlib> // calloc
#if defined(PKTALLOC_ENABLE_ALLOCATOR_INTEGRITY_CHECKS) && defined(PKTALLOC_DEBUG)
#define ALLOC_DEBUG_INTEGRITY_CHECK() IntegrityCheck();
#else // PKTALLOC_ENABLE_ALLOCATOR_INTEGRITY_CHECKS
#define ALLOC_DEBUG_INTEGRITY_CHECK() do {} while (false);
#endif // PKTALLOC_ENABLE_ALLOCATOR_INTEGRITY_CHECKS
namespace pktalloc {
//------------------------------------------------------------------------------
// SIMD-Safe Aligned Memory Allocations
static inline uint8_t* SIMDSafeAllocate(size_t size)
{
uint8_t* data = (uint8_t*)calloc(1, kAlignmentBytes + size);
if (!data) {
return nullptr;
}
unsigned offset = (unsigned)((uintptr_t)data % kAlignmentBytes);
data += kAlignmentBytes - offset;
data[-1] = (uint8_t)offset;
return data;
}
static inline void SIMDSafeFree(void* ptr)
{
if (!ptr) {
return;
}
uint8_t* data = (uint8_t*)ptr;
unsigned offset = data[-1];
if (offset >= kAlignmentBytes) {
PKTALLOC_DEBUG_BREAK(); // Should never happen
return;
}
data -= kAlignmentBytes - offset;
free(data);
}
//------------------------------------------------------------------------------
// Allocator
Allocator::Allocator()
{
static_assert(kAlignmentBytes == kUnitSize, "update SIMDSafeAllocate");
PreferredWindows.SetSize_NoCopy(kPreallocatedWindows);
HugeChunkStart = SIMDSafeAllocate(kWindowSizeBytes * kPreallocatedWindows);
if (HugeChunkStart)
{
uint8_t* windowStart = HugeChunkStart;
// For each window to preallocate:
for (unsigned i = 0; i < kPreallocatedWindows; ++i)
{
WindowHeader* window = (WindowHeader*)windowStart;
windowStart += kWindowSizeBytes;
window->Used.ClearAll();
window->FreeUnitCount = kWindowMaxUnits;
window->ResumeScanOffset = 0;
window->Preallocated = true;
window->FullListIndex = kNotInFullList;
PreferredWindows.GetRef(i) = window;
}
}
ALLOC_DEBUG_INTEGRITY_CHECK();
}
Allocator::~Allocator()
{
for (unsigned i = 0, count = PreferredWindows.GetSize(); i < count; ++i)
{
WindowHeader* window = PreferredWindows.GetRef(i);
PKTALLOC_DEBUG_ASSERT(window != nullptr);
if (window && !window->Preallocated) {
SIMDSafeFree(window);
}
}
for (unsigned i = 0, count = FullWindows.GetSize(); i < count; ++i)
{
WindowHeader* window = FullWindows.GetRef(i);
PKTALLOC_DEBUG_ASSERT(window != nullptr);
if (window && !window->Preallocated) {
SIMDSafeFree(window);
}
}
SIMDSafeFree(HugeChunkStart);
}
unsigned Allocator::GetMemoryUsedBytes() const
{
unsigned sum = 0;
for (unsigned i = 0, count = PreferredWindows.GetSize(); i < count; ++i)
{
WindowHeader* window = PreferredWindows.GetRef(i);
PKTALLOC_DEBUG_ASSERT(window != nullptr);
if (window) {
sum += kWindowMaxUnits - window->FreeUnitCount;
}
}
for (unsigned i = 0, count = FullWindows.GetSize(); i < count; ++i)
{
WindowHeader* window = FullWindows.GetRef(i);
PKTALLOC_DEBUG_ASSERT(window != nullptr);
if (window) {
sum += kWindowMaxUnits - window->FreeUnitCount;
}
}
return sum * kUnitSize;
}
unsigned Allocator::GetMemoryAllocatedBytes() const
{
return (unsigned)((PreferredWindows.GetSize() + FullWindows.GetSize()) * kWindowMaxUnits * kUnitSize);
}
bool Allocator::IntegrityCheck() const
{
#ifdef PKTALLOC_SHRINK
PKTALLOC_DEBUG_ASSERT(PreferredWindows.GetSize() >= EmptyWindowCount);
#endif // PKTALLOC_SHRINK
unsigned emptyCount = 0;
unsigned preallocatedCount = 0;
// Check preferred windows list:
for (unsigned i = 0, icount = PreferredWindows.GetSize(); i < icount; ++i)
{
WindowHeader* window = PreferredWindows.GetRef(i);
if (!window || window->FullListIndex != kNotInFullList)
{
PKTALLOC_DEBUG_BREAK(); // Null found
return false;
}
for (unsigned j = 0, jcount = PreferredWindows.GetSize(); j < jcount; ++j)
{
WindowHeader* other = PreferredWindows.GetRef(j);
if (window == other && i != j)
{
PKTALLOC_DEBUG_BREAK(); // Duplicate found
return false;
}
}
if (window->FreeUnitCount <= 0 || window->FreeUnitCount > kWindowMaxUnits)
{
PKTALLOC_DEBUG_BREAK(); // Invalid FreeUnitCount
return false;
}
if (window->ResumeScanOffset > kWindowMaxUnits)
{
PKTALLOC_DEBUG_BREAK(); // Invalid ResumeScanOffset
return false;
}
const unsigned setCount = window->Used.RangePopcount(0, kWindowMaxUnits);
if (setCount != kWindowMaxUnits - window->FreeUnitCount)
{
PKTALLOC_DEBUG_BREAK(); // Bitfield does not match FreeUnitCount
return false;
}
if (window->Preallocated) {
++preallocatedCount;
}
else if (window->FreeUnitCount == kWindowMaxUnits) {
++emptyCount;
}
}
// Check full windows list:
for (unsigned i = 0, icount = FullWindows.GetSize(); i < icount; ++i)
{
WindowHeader* window = FullWindows.GetRef(i);
if (!window || window->FullListIndex != (int)i) {
PKTALLOC_DEBUG_BREAK(); // Null pointer
return false;
}
for (unsigned j = 0, jcount = PreferredWindows.GetSize(); j < jcount; ++j)
{
WindowHeader* other = PreferredWindows.GetRef(j);
if (window == other)
{
PKTALLOC_DEBUG_BREAK(); // Duplicate
return false;
}
}
for (unsigned j = 0, jcount = FullWindows.GetSize(); j < jcount; ++j)
{
WindowHeader* other = FullWindows.GetRef(j);
if (window == other && i != j)
{
PKTALLOC_DEBUG_BREAK(); // Duplicate
return false;
}
}
#if 0
// TBD: Investigate this one further
if (window->FreeUnitCount > kPreferredThresholdUnits) {
PKTALLOC_DEBUG_BREAK(); // Invalid FreeUnitCount
return false;
}
#endif
if (window->ResumeScanOffset > kWindowMaxUnits) {
PKTALLOC_DEBUG_BREAK(); // Invalid ResumeScanOffset
return false;
}
const unsigned setCount = window->Used.RangePopcount(0, kWindowMaxUnits);
if (setCount != kWindowMaxUnits - window->FreeUnitCount) {
PKTALLOC_DEBUG_BREAK(); // Bitfield does not match FreeUnitCount
return false;
}
if (window->Preallocated) {
++preallocatedCount;
}
}
if (preallocatedCount != kPreallocatedWindows) {
PKTALLOC_DEBUG_BREAK(); // Lost a preallocated window
return false;
}
#ifdef PKTALLOC_SHRINK
if (emptyCount != EmptyWindowCount) {
PKTALLOC_DEBUG_BREAK(); // EmptyWindowCount does not match
return false;
}
#endif // PKTALLOC_SHRINK
return true;
}
uint8_t* Allocator::Allocate(unsigned bytes)
{
if (bytes <= 0) {
return nullptr;
}
ALLOC_DEBUG_INTEGRITY_CHECK();
// Calculate number of units required by this allocation
// Note: +1 for the AllocationHeader
const unsigned units = (bytes + kUnitSize - 1) / kUnitSize + 1;
if (units > kFallbackThresholdUnits) {
return fallbackAllocate(bytes);
}
// Check preferred windows list:
const unsigned preferredCount = PreferredWindows.GetSize();
for (int i = (int)preferredCount - 1; i >= 0; --i)
{
WindowHeader* window = PreferredWindows.GetRef(i);
PKTALLOC_DEBUG_ASSERT(window);
if (window->FreeUnitCount < units) {
continue;
}
// Walk the holes in the bitmask:
UsedMaskT* usedPtr = &window->Used;
unsigned regionStart = window->ResumeScanOffset;
while (regionStart < UsedMaskT::kValidBits)
{
regionStart = usedPtr->FindFirstClear(regionStart);
unsigned regionEnd = regionStart + units;
// If we ran out of space:
if (regionEnd > UsedMaskT::kValidBits) {
break;
}
regionEnd = usedPtr->FindFirstSet(regionStart + 1, regionEnd);
PKTALLOC_DEBUG_ASSERT(regionEnd > regionStart);
PKTALLOC_DEBUG_ASSERT(regionEnd <= UsedMaskT::kValidBits);
if (regionEnd - regionStart < units)
{
regionStart = regionEnd + 1;
continue;
}
regionEnd = regionStart + units;
// Carve out region
uint8_t* region = (uint8_t*)window + kWindowHeaderBytes + regionStart * kUnitSize;
AllocationHeader* regionHeader = (AllocationHeader*)region;
#ifdef PKTALLOC_DEBUG
regionHeader->Canary = AllocationHeader::kCanaryExpected;
#endif // PKTALLOC_DEBUG
regionHeader->Header = window;
regionHeader->UsedUnits = units;
// Update window header
#ifdef PKTALLOC_SHRINK
if (window->FreeUnitCount >= kWindowMaxUnits &&
!window->Preallocated)
{
PKTALLOC_DEBUG_ASSERT(EmptyWindowCount > 0);
--EmptyWindowCount;
}
#endif // PKTALLOC_SHRINK
window->FreeUnitCount -= units;
usedPtr->SetRange(regionStart, regionStart + units);
window->ResumeScanOffset = regionStart + units;
// Any prior windows that failed to allocate are moved to full list
unsigned fullCount = preferredCount - 1 - i;
// Move this window to the full list if we cannot make another allocation of the same size
if (regionStart + units * 2 > kWindowMaxUnits) {
// Include this one too
++fullCount;
}
moveLastFewWindowsToFull(fullCount);
uint8_t* data = region + kUnitSize;
#ifdef PKTALLOC_SCRUB_MEMORY
memset(data, 0, (units - 1) * kUnitSize);
#endif // PKTALLOC_SCRUB_MEMORY
PKTALLOC_DEBUG_ASSERT((uintptr_t)data % kUnitSize == 0);
PKTALLOC_DEBUG_ASSERT((uint8_t*)regionHeader >= (uint8_t*)regionHeader->Header + kWindowHeaderBytes);
PKTALLOC_DEBUG_ASSERT(regionHeader->GetUnitStart() < kWindowMaxUnits);
PKTALLOC_DEBUG_ASSERT(regionHeader->GetUnitStart() + regionHeader->UsedUnits <= kWindowMaxUnits);
return data;
}
}
// Move all preferred windows to full since none of them worked out
moveLastFewWindowsToFull(preferredCount);
return allocateFromNewWindow(units);
}
void Allocator::moveLastFewWindowsToFull(unsigned count)
{
const unsigned existingFullCount = FullWindows.GetSize();
FullWindows.SetSize_Copy(existingFullCount + count);
const unsigned existingPreferredCount = PreferredWindows.GetSize();
PKTALLOC_DEBUG_ASSERT(existingPreferredCount >= count);
// For each window to move:
for (unsigned i = 0; i < count; ++i)
{
const unsigned windowIndex = existingPreferredCount - 1 - i;
PKTALLOC_DEBUG_ASSERT(windowIndex < PreferredWindows.GetSize());
WindowHeader* window = PreferredWindows.GetRef(windowIndex);
PKTALLOC_DEBUG_ASSERT(window);
// Move the window to the full list
FullWindows.GetRef(existingFullCount + i) = window;
window->FullListIndex = existingFullCount + i;
}
PreferredWindows.SetSize_Copy(existingPreferredCount - count);
ALLOC_DEBUG_INTEGRITY_CHECK();
}
uint8_t* Allocator::allocateFromNewWindow(unsigned units)
{
ALLOC_DEBUG_INTEGRITY_CHECK();
uint8_t* headerStart = SIMDSafeAllocate(kWindowSizeBytes);
if (!headerStart) {
return nullptr; // Allocation failure
}
// Update window header
WindowHeader* window = (WindowHeader*)headerStart;
window->Used.ClearAll();
window->Used.SetRange(0, units);
window->FreeUnitCount = kWindowMaxUnits - units;
window->ResumeScanOffset = units;
window->Preallocated = false;
PKTALLOC_DEBUG_ASSERT(PreferredWindows.GetSize() == 0);
window->FullListIndex = kNotInFullList;
PreferredWindows.Append(window);
// Carve out region
AllocationHeader* regionHeader = (AllocationHeader*)(headerStart + kWindowHeaderBytes);
#ifdef PKTALLOC_DEBUG
regionHeader->Canary = AllocationHeader::kCanaryExpected;
#endif // PKTALLOC_DEBUG
regionHeader->Header = window;
regionHeader->UsedUnits = units;
uint8_t* data = (uint8_t*)regionHeader + kUnitSize;
#ifdef PKTALLOC_SCRUB_MEMORY
memset(data, 0, (units - 1) * kUnitSize);
#endif // PKTALLOC_SCRUB_MEMORY
PKTALLOC_DEBUG_ASSERT((uintptr_t)data % kUnitSize == 0);
ALLOC_DEBUG_INTEGRITY_CHECK();
return data;
}
uint8_t* Allocator::Reallocate(uint8_t* ptr, unsigned bytes, Realloc behavior)
{
ALLOC_DEBUG_INTEGRITY_CHECK();
if (!ptr) {
return Allocate(bytes);
}
if (bytes <= 0) {
Free(ptr);
return nullptr;
}
PKTALLOC_DEBUG_ASSERT((uintptr_t)ptr % kUnitSize == 0);
AllocationHeader* regionHeader = (AllocationHeader*)(ptr - kUnitSize);
#ifdef PKTALLOC_DEBUG
if (regionHeader->Canary != AllocationHeader::kCanaryExpected) {
PKTALLOC_DEBUG_BREAK(); // Buffer overflow detected
return nullptr;
}
if (regionHeader->IsFreed()) {
PKTALLOC_DEBUG_BREAK(); // Double-free
return nullptr;
}
#endif // PKTALLOC_DEBUG
const unsigned existingUnits = regionHeader->UsedUnits;
#ifndef PKTALLOC_DISABLE
PKTALLOC_DEBUG_ASSERT(!regionHeader->Header || existingUnits <= kFallbackThresholdUnits);
#endif // PKTALLOC_DISABLE
// If the existing allocation is big enough:
const unsigned requestedUnits = (bytes + kUnitSize - 1) / kUnitSize + 1;
if (requestedUnits <= existingUnits) {
return ptr; // No change needed
}
// Allocate new data
uint8_t* newPtr = Allocate(bytes);
if (!newPtr) {
return nullptr;
}
// Copy old data
if (behavior == Realloc::CopyExisting) {
memcpy(newPtr, ptr, (existingUnits - 1) * kUnitSize);
}
Free(ptr);
ALLOC_DEBUG_INTEGRITY_CHECK();
return newPtr;
}
void Allocator::Shrink(uint8_t* ptr, unsigned bytes)
{
ALLOC_DEBUG_INTEGRITY_CHECK();
if (!ptr) {
return;
}
PKTALLOC_DEBUG_ASSERT((uintptr_t)ptr % kUnitSize == 0);
AllocationHeader* regionHeader = (AllocationHeader*)(ptr - kUnitSize);
#ifdef PKTALLOC_DEBUG
if (regionHeader->Canary != AllocationHeader::kCanaryExpected) {
PKTALLOC_DEBUG_BREAK(); // Buffer overflow detected
return;
}
#endif // PKTALLOC_DEBUG
if (regionHeader->IsFreed()) {
PKTALLOC_DEBUG_BREAK(); // Double-free
return;
}
// Calculate number of units required by this allocation
// Note: +1 for the AllocationHeader
const unsigned unitsNeeded = (bytes + kUnitSize - 1) / kUnitSize + 1;
const unsigned unitsCurrent = regionHeader->UsedUnits;
// If the allocation can shrink:
if (unitsNeeded < unitsCurrent)
{
WindowHeader* windowHeader = regionHeader->Header;
if (!windowHeader) {
// Fallback allocation: We cannot resize this region
return;
}
PKTALLOC_DEBUG_ASSERT((uint8_t*)regionHeader >= (uint8_t*)regionHeader->Header + kWindowHeaderBytes);
const unsigned regionStart = regionHeader->GetUnitStart();
PKTALLOC_DEBUG_ASSERT(regionStart < kWindowMaxUnits);
PKTALLOC_DEBUG_ASSERT(regionStart + regionHeader->UsedUnits <= kWindowMaxUnits);
const unsigned regionEndNew = regionStart + unitsNeeded;
PKTALLOC_DEBUG_ASSERT(regionEndNew <= kWindowMaxUnits);
PKTALLOC_DEBUG_ASSERT((regionStart + unitsCurrent) > regionEndNew);
// Resume scanning from this hole next time
if (windowHeader->ResumeScanOffset > regionEndNew) {
windowHeader->ResumeScanOffset = regionEndNew;
}
// Clear the units we gave up
windowHeader->Used.ClearRange(regionEndNew, regionStart + unitsCurrent);
// Give back the unit count
windowHeader->FreeUnitCount += unitsCurrent - unitsNeeded;
// Update unit count
regionHeader->UsedUnits = unitsNeeded;
// Note that this will not move a full window to the empty list,
// but when this allocation is freed it may be added later.
}
ALLOC_DEBUG_INTEGRITY_CHECK();
}
void Allocator::Free(uint8_t* ptr)
{
ALLOC_DEBUG_INTEGRITY_CHECK();
if (!ptr) {
return;
}
PKTALLOC_DEBUG_ASSERT((uintptr_t)ptr % kUnitSize == 0);
AllocationHeader* regionHeader = (AllocationHeader*)(ptr - kUnitSize);
#ifdef PKTALLOC_DEBUG
if (regionHeader->Canary != AllocationHeader::kCanaryExpected) {
PKTALLOC_DEBUG_BREAK(); // Buffer overflow detected
return;
}
#endif // PKTALLOC_DEBUG
if (regionHeader->IsFreed()) {
PKTALLOC_DEBUG_BREAK(); // Double-free
return;
}
WindowHeader* window = regionHeader->Header;
if (!window)
{
regionHeader->UsedUnits = 0; // Mark freed
fallbackFree(ptr);
return;
}
const unsigned units = regionHeader->UsedUnits;
PKTALLOC_DEBUG_ASSERT(units >= 2 && units <= kFallbackThresholdUnits);
regionHeader->UsedUnits = 0; // Mark freed
PKTALLOC_DEBUG_ASSERT((uint8_t*)regionHeader >= (uint8_t*)regionHeader->Header + kWindowHeaderBytes);
unsigned regionStart = regionHeader->GetUnitStart();
PKTALLOC_DEBUG_ASSERT(regionStart < kWindowMaxUnits);
PKTALLOC_DEBUG_ASSERT(regionStart + units <= kWindowMaxUnits);
unsigned regionEnd = regionStart + units;
// Resume scanning from this hole next time
if (window->ResumeScanOffset > regionStart) {
window->ResumeScanOffset = regionStart;
}
// Clear the units it was using
window->Used.ClearRange(regionStart, regionEnd);
// Give back the unit count
window->FreeUnitCount += units;
// If we may want to promote this to Preferred:
if (window->FreeUnitCount >= kPreferredThresholdUnits &&
window->FullListIndex != kNotInFullList)
{
// Restart scanning from the front
window->ResumeScanOffset = 0;
// Swap last item in full list into the slot
const unsigned fullCount = FullWindows.GetSize();
const unsigned fullIndex = (unsigned)window->FullListIndex;
PKTALLOC_DEBUG_ASSERT(fullIndex < fullCount);
PKTALLOC_DEBUG_ASSERT(fullCount > 0);
if (fullIndex < fullCount - 1)
{
WindowHeader* replacement = FullWindows.GetRef(fullCount - 1);
FullWindows.GetRef(fullIndex) = replacement;
replacement->FullListIndex = fullIndex;
}
FullWindows.SetSize_Copy(fullCount - 1);
window->FullListIndex = kNotInFullList;
PreferredWindows.Append(window);
}
#ifdef PKTALLOC_SHRINK
// If we should do some bulk cleanup:
if (window->FreeUnitCount >= kWindowMaxUnits &&
!window->Preallocated &&
++EmptyWindowCount >= kEmptyWindowCleanupThreshold)
{
freeEmptyWindows();
}
#endif // PKTALLOC_SHRINK
ALLOC_DEBUG_INTEGRITY_CHECK();
}
#ifdef PKTALLOC_SHRINK
void Allocator::freeEmptyWindows()
{
if (EmptyWindowCount <= kEmptyWindowMinimum) {
return;
}
ALLOC_DEBUG_INTEGRITY_CHECK();
// Check full windows list:
unsigned count = PreferredWindows.GetSize();
for (unsigned i = 0; i < count;)
{
WindowHeader* window = PreferredWindows.GetRef(i);
PKTALLOC_DEBUG_ASSERT(window && window->FullListIndex == kNotInFullList);
// If this window cannot be reclaimed:
if (window->FreeUnitCount < kWindowMaxUnits ||
window->Preallocated)
{
++i;
continue;
}
SIMDSafeFree(window);
PKTALLOC_DEBUG_ASSERT(count > 0);
--count;
PreferredWindows.GetRef(i) = PreferredWindows.GetRef(count);
PKTALLOC_DEBUG_ASSERT(EmptyWindowCount > 0);
if (--EmptyWindowCount <= kEmptyWindowMinimum) {
break;
}
}
PreferredWindows.SetSize_Copy(count);
ALLOC_DEBUG_INTEGRITY_CHECK();
}
#endif // PKTALLOC_SHRINK
uint8_t* Allocator::fallbackAllocate(unsigned bytes)
{
// Calculate number of units required by this allocation
// Note: +1 for the AllocationHeader
const unsigned units = (bytes + kUnitSize - 1) / kUnitSize + 1;
uint8_t* ptr = SIMDSafeAllocate(kUnitSize * units);
if (!ptr) {
return nullptr;
}
AllocationHeader* regionHeader = (AllocationHeader*)ptr;
#ifdef PKTALLOC_DEBUG
regionHeader->Canary = AllocationHeader::kCanaryExpected;
#endif // PKTALLOC_DEBUG
regionHeader->Header = nullptr;
regionHeader->UsedUnits = units;
return ptr + kUnitSize;
}
void Allocator::fallbackFree(uint8_t* ptr)
{
PKTALLOC_DEBUG_ASSERT(ptr);
SIMDSafeFree(ptr - kUnitSize);
}
} // namespace pktalloc
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