Commit 5ce68669 authored by Sigurd Schneider's avatar Sigurd Schneider Committed by Commit Bot

Enable alignment checks when reading object fields

Drive-by: Fix alignment bugs caused by DCHECKS.

Bug: v8:9264

Change-Id: I0836b1d08fea2ce11d8f7929e12f303b6ae06efe
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1617676
Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
Reviewed-by: 's avatarIgor Sheludko <ishell@chromium.org>
Reviewed-by: 's avatarJakob Kummerow <jkummerow@chromium.org>
Reviewed-by: 's avatarUlan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61643}
parent bf372a73
......@@ -5690,7 +5690,7 @@ void VerifySmisVisitor::VisitRootPointers(Root root, const char* description,
}
}
bool Heap::AllowedToBeMigrated(HeapObject obj, AllocationSpace dst) {
bool Heap::AllowedToBeMigrated(Map map, HeapObject obj, AllocationSpace dst) {
// Object migration is governed by the following rules:
//
// 1) Objects in new-space can be migrated to the old space
......@@ -5703,8 +5703,8 @@ bool Heap::AllowedToBeMigrated(HeapObject obj, AllocationSpace dst) {
//
// Since this function is used for debugging only, we do not place
// asserts here, but check everything explicitly.
if (obj->map() == ReadOnlyRoots(this).one_pointer_filler_map()) return false;
InstanceType type = obj->map()->instance_type();
if (map == ReadOnlyRoots(this).one_pointer_filler_map()) return false;
InstanceType type = map->instance_type();
MemoryChunk* chunk = MemoryChunk::FromHeapObject(obj);
AllocationSpace src = chunk->owner()->identity();
switch (src) {
......
......@@ -464,7 +464,7 @@ class Heap {
// Checks whether the given object is allowed to be migrated from it's
// current space into the given destination space. Used for debugging.
bool AllowedToBeMigrated(HeapObject object, AllocationSpace dest);
bool AllowedToBeMigrated(Map map, HeapObject object, AllocationSpace dest);
void CheckHandleCount();
......
......@@ -1231,7 +1231,7 @@ class EvacuateVisitorBase : public HeapObjectVisitor {
HeapObject src, int size, AllocationSpace dest) {
Address dst_addr = dst->address();
Address src_addr = src->address();
DCHECK(base->heap_->AllowedToBeMigrated(src, dest));
DCHECK(base->heap_->AllowedToBeMigrated(src->map(), src, dest));
DCHECK_NE(dest, LO_SPACE);
DCHECK_NE(dest, CODE_LO_SPACE);
if (dest == OLD_SPACE) {
......
......@@ -135,7 +135,7 @@ CopyAndForwardResult Scavenger::SemiSpaceCopyObject(
static_assert(std::is_same<THeapObjectSlot, FullHeapObjectSlot>::value ||
std::is_same<THeapObjectSlot, HeapObjectSlot>::value,
"Only FullHeapObjectSlot and HeapObjectSlot are expected here");
DCHECK(heap()->AllowedToBeMigrated(object, NEW_SPACE));
DCHECK(heap()->AllowedToBeMigrated(map, object, NEW_SPACE));
AllocationAlignment alignment = HeapObject::RequiredAlignment(map);
AllocationResult allocation =
allocator_.Allocate(NEW_SPACE, object_size, alignment);
......
......@@ -463,7 +463,6 @@ void Scavenger::Process(OneshotBarrier* barrier) {
struct PromotionListEntry entry;
while (promotion_list_.Pop(&entry)) {
HeapObject target = entry.heap_object;
DCHECK(!target->IsMap());
IterateAndScavengePromotedObject(target, entry.map, entry.size);
done = false;
if (have_barrier && ((++objects % kInterruptThreshold) == 0)) {
......
......@@ -66,8 +66,11 @@ CAST_ACCESSOR(WeakArrayList)
SYNCHRONIZED_SMI_ACCESSORS(FixedArrayBase, length, kLengthOffset)
int FixedArrayBase::length() const {
DCHECK(!IsInRange(map()->instance_type(), FIRST_FIXED_TYPED_ARRAY_TYPE,
#ifdef DEBUG
DCHECK(map_word().IsForwardingAddress() ||
!IsInRange(map()->instance_type(), FIRST_FIXED_TYPED_ARRAY_TYPE,
LAST_FIXED_TYPED_ARRAY_TYPE));
#endif
Object value = READ_FIELD(*this, kLengthOffset);
return Smi::ToInt(value);
}
......
......@@ -336,13 +336,14 @@
} \
} while (false)
#define READ_DOUBLE_FIELD(p, offset) ReadDoubleValue(FIELD_ADDR(p, offset))
// BUG(v8:8875): Double fields may be unaligned.
#define READ_DOUBLE_FIELD(p, offset) \
ReadUnalignedValue<double>(FIELD_ADDR(p, offset))
#define WRITE_DOUBLE_FIELD(p, offset, value) \
WriteDoubleValue(FIELD_ADDR(p, offset), value)
WriteUnalignedValue<double>(FIELD_ADDR(p, offset), value)
#define READ_INT_FIELD(p, offset) \
(*reinterpret_cast<const int*>(FIELD_ADDR(p, offset)))
#define READ_INT_FIELD(p, offset) (Memory<const int>(FIELD_ADDR(p, offset)))
#define WRITE_INT_FIELD(p, offset, value) \
(*reinterpret_cast<int*>(FIELD_ADDR(p, offset)) = value)
......@@ -352,7 +353,7 @@
reinterpret_cast<const base::Atomic32*>(FIELD_ADDR(p, offset))))
#define READ_UINT8_FIELD(p, offset) \
(*reinterpret_cast<const uint8_t*>(FIELD_ADDR(p, offset)))
(Memory<const uint8_t>(FIELD_ADDR(p, offset)))
#define WRITE_UINT8_FIELD(p, offset, value) \
(*reinterpret_cast<uint8_t*>(FIELD_ADDR(p, offset)) = value)
......@@ -361,8 +362,7 @@
base::Relaxed_Store(reinterpret_cast<base::Atomic8*>(FIELD_ADDR(p, offset)), \
static_cast<base::Atomic8>(value));
#define READ_INT8_FIELD(p, offset) \
(*reinterpret_cast<const int8_t*>(FIELD_ADDR(p, offset)))
#define READ_INT8_FIELD(p, offset) (Memory<const int8_t>(FIELD_ADDR(p, offset)))
#define RELAXED_READ_INT8_FIELD(p, offset) \
static_cast<int8_t>(base::Relaxed_Load( \
......@@ -372,13 +372,13 @@
(*reinterpret_cast<int8_t*>(FIELD_ADDR(p, offset)) = value)
#define READ_UINT16_FIELD(p, offset) \
(*reinterpret_cast<const uint16_t*>(FIELD_ADDR(p, offset)))
(Memory<const uint16_t>(FIELD_ADDR(p, offset)))
#define WRITE_UINT16_FIELD(p, offset, value) \
(*reinterpret_cast<uint16_t*>(FIELD_ADDR(p, offset)) = value)
#define READ_INT16_FIELD(p, offset) \
(*reinterpret_cast<const int16_t*>(FIELD_ADDR(p, offset)))
(Memory<const int16_t>(FIELD_ADDR(p, offset)))
#define WRITE_INT16_FIELD(p, offset, value) \
(*reinterpret_cast<int16_t*>(FIELD_ADDR(p, offset)) = value)
......@@ -392,8 +392,7 @@
reinterpret_cast<base::Atomic16*>(FIELD_ADDR(p, offset)), \
static_cast<base::Atomic16>(value));
#define READ_UINT32_FIELD(p, offset) \
(*reinterpret_cast<const uint32_t*>(FIELD_ADDR(p, offset)))
#define READ_UINT32_FIELD(p, offset) (Memory<uint32_t>(FIELD_ADDR(p, offset)))
#define RELAXED_READ_UINT32_FIELD(p, offset) \
static_cast<uint32_t>(base::Relaxed_Load( \
......@@ -407,8 +406,7 @@
reinterpret_cast<base::Atomic32*>(FIELD_ADDR(p, offset)), \
static_cast<base::Atomic32>(value));
#define READ_INT32_FIELD(p, offset) \
(*reinterpret_cast<const int32_t*>(FIELD_ADDR(p, offset)))
#define READ_INT32_FIELD(p, offset) (Memory<int32_t>(FIELD_ADDR(p, offset)))
#define RELAXED_READ_INT32_FIELD(p, offset) \
static_cast<int32_t>(base::Relaxed_Load( \
......@@ -427,8 +425,7 @@
reinterpret_cast<base::Atomic32*>(FIELD_ADDR(p, offset)), \
static_cast<base::Atomic32>(value));
#define READ_FLOAT_FIELD(p, offset) \
(*reinterpret_cast<const float*>(FIELD_ADDR(p, offset)))
#define READ_FLOAT_FIELD(p, offset) (Memory<const float>(FIELD_ADDR(p, offset)))
#define WRITE_FLOAT_FIELD(p, offset, value) \
(*reinterpret_cast<float*>(FIELD_ADDR(p, offset)) = value)
......@@ -459,28 +456,24 @@
#else // V8_COMPRESS_POINTERS
#define READ_INTPTR_FIELD(p, offset) \
(*reinterpret_cast<const intptr_t*>(FIELD_ADDR(p, offset)))
#define READ_INTPTR_FIELD(p, offset) (Memory<intptr_t>(FIELD_ADDR(p, offset)))
#define WRITE_INTPTR_FIELD(p, offset, value) \
(*reinterpret_cast<intptr_t*>(FIELD_ADDR(p, offset)) = value)
#define READ_UINTPTR_FIELD(p, offset) \
(*reinterpret_cast<const uintptr_t*>(FIELD_ADDR(p, offset)))
#define READ_UINTPTR_FIELD(p, offset) (Memory<uintptr_t>(FIELD_ADDR(p, offset)))
#define WRITE_UINTPTR_FIELD(p, offset, value) \
(*reinterpret_cast<uintptr_t*>(FIELD_ADDR(p, offset)) = value)
#define READ_UINT64_FIELD(p, offset) \
(*reinterpret_cast<const uint64_t*>(FIELD_ADDR(p, offset)))
#define READ_UINT64_FIELD(p, offset) (Memory<uint64_t>(FIELD_ADDR(p, offset)))
#define WRITE_UINT64_FIELD(p, offset, value) \
(*reinterpret_cast<uint64_t*>(FIELD_ADDR(p, offset)) = value)
#endif // V8_COMPRESS_POINTERS
#define READ_BYTE_FIELD(p, offset) \
(*reinterpret_cast<const byte*>(FIELD_ADDR(p, offset)))
#define READ_BYTE_FIELD(p, offset) (Memory<byte>(FIELD_ADDR(p, offset)))
#define RELAXED_READ_BYTE_FIELD(p, offset) \
static_cast<byte>(base::Relaxed_Load( \
......
......@@ -5,6 +5,7 @@
#ifndef V8_V8MEMORY_H_
#define V8_V8MEMORY_H_
#include "src/base/macros.h"
#include "src/globals.h"
namespace v8 {
......@@ -15,13 +16,12 @@ namespace internal {
// Note that this class currently relies on undefined behaviour. There is a
// proposal (http://wg21.link/p0593r2) to make it defined behaviour though.
template <class T>
T& Memory(Address addr) {
// {addr} must be aligned.
DCHECK_EQ(0, addr & (alignof(T) - 1));
inline T& Memory(Address addr) {
DCHECK(IsAligned(addr, alignof(T)));
return *reinterpret_cast<T*>(addr);
}
template <class T>
T& Memory(byte* addr) {
inline T& Memory(byte* addr) {
return Memory<T>(reinterpret_cast<Address>(addr));
}
......@@ -39,18 +39,6 @@ static inline void WriteUnalignedValue(Address p, V value) {
memcpy(reinterpret_cast<void*>(p), &value, sizeof(V));
}
static inline double ReadFloatValue(Address p) {
return ReadUnalignedValue<float>(p);
}
static inline double ReadDoubleValue(Address p) {
return ReadUnalignedValue<double>(p);
}
static inline void WriteDoubleValue(Address p, double value) {
WriteUnalignedValue(p, value);
}
static inline uint16_t ReadUnalignedUInt16(Address p) {
return ReadUnalignedValue<uint16_t>(p);
}
......
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