[compiler-rt] r326206 - [scudo] Introduce Chunk::getHeaderSize
Kostya Kortchinsky via llvm-commits
llvm-commits at lists.llvm.org
Tue Feb 27 08:14:49 PST 2018
Author: cryptoad
Date: Tue Feb 27 08:14:49 2018
New Revision: 326206
URL: http://llvm.org/viewvc/llvm-project?rev=326206&view=rev
Log:
[scudo] Introduce Chunk::getHeaderSize
Summary:
Instead of using `AlignedChunkHeaderSize`, introduce a `constexpr` function
`getHeaderSize` in the `Chunk` namespace. Switch `RoundUpTo` to a `constexpr`
as well (so we can use it in `constexpr` declarations). Mark a few variables
in the areas touched as `const`.
Overall this has no functional change, and is mostly to make things a bit more
consistent.
Reviewers: alekseyshl
Reviewed By: alekseyshl
Subscribers: delcypher, #sanitizers, llvm-commits
Differential Revision: https://reviews.llvm.org/D43772
Modified:
compiler-rt/trunk/lib/scudo/scudo_allocator.cpp
compiler-rt/trunk/lib/scudo/scudo_allocator.h
compiler-rt/trunk/lib/scudo/scudo_allocator_secondary.h
Modified: compiler-rt/trunk/lib/scudo/scudo_allocator.cpp
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/scudo/scudo_allocator.cpp?rev=326206&r1=326205&r2=326206&view=diff
==============================================================================
--- compiler-rt/trunk/lib/scudo/scudo_allocator.cpp (original)
+++ compiler-rt/trunk/lib/scudo/scudo_allocator.cpp Tue Feb 27 08:14:49 2018
@@ -69,18 +69,17 @@ namespace Chunk {
// prevent this, we work with a local copy of the header.
static INLINE void *getBackendPtr(const void *Ptr, UnpackedHeader *Header) {
return reinterpret_cast<void *>(reinterpret_cast<uptr>(Ptr) -
- AlignedChunkHeaderSize -
- (Header->Offset << MinAlignmentLog));
+ getHeaderSize() - (Header->Offset << MinAlignmentLog));
}
static INLINE AtomicPackedHeader *getAtomicHeader(void *Ptr) {
return reinterpret_cast<AtomicPackedHeader *>(reinterpret_cast<uptr>(Ptr) -
- AlignedChunkHeaderSize);
+ getHeaderSize());
}
static INLINE
const AtomicPackedHeader *getConstAtomicHeader(const void *Ptr) {
return reinterpret_cast<const AtomicPackedHeader *>(
- reinterpret_cast<uptr>(Ptr) - AlignedChunkHeaderSize);
+ reinterpret_cast<uptr>(Ptr) - getHeaderSize());
}
static INLINE bool isAligned(const void *Ptr) {
@@ -92,9 +91,8 @@ namespace Chunk {
static INLINE uptr getUsableSize(const void *Ptr, UnpackedHeader *Header) {
const uptr Size = getBackendAllocator().getActuallyAllocatedSize(
getBackendPtr(Ptr, Header), Header->ClassId);
- if (Size == 0)
- return 0;
- return Size - AlignedChunkHeaderSize - (Header->Offset << MinAlignmentLog);
+ DCHECK_NE(Size, 0);
+ return Size - getHeaderSize() - (Header->Offset << MinAlignmentLog);
}
// Compute the checksum of the chunk pointer and its header.
@@ -251,7 +249,7 @@ struct ScudoAllocator {
const uptr MaxPrimaryAlignment =
1 << MostSignificantSetBitIndex(SizeClassMap::kMaxSize - MinAlignment);
const uptr MaxOffset =
- (MaxPrimaryAlignment - AlignedChunkHeaderSize) >> MinAlignmentLog;
+ (MaxPrimaryAlignment - Chunk::getHeaderSize()) >> MinAlignmentLog;
Header.Offset = MaxOffset;
if (Header.Offset != MaxOffset) {
dieWithMessage("ERROR: the maximum possible offset doesn't fit in the "
@@ -368,9 +366,10 @@ struct ScudoAllocator {
if (UNLIKELY(Size == 0))
Size = 1;
- uptr NeededSize = RoundUpTo(Size, MinAlignment) + AlignedChunkHeaderSize;
- uptr AlignedSize = (Alignment > MinAlignment) ?
- NeededSize + (Alignment - AlignedChunkHeaderSize) : NeededSize;
+ const uptr NeededSize = RoundUpTo(Size, MinAlignment) +
+ Chunk::getHeaderSize();
+ const uptr AlignedSize = (Alignment > MinAlignment) ?
+ NeededSize + (Alignment - Chunk::getHeaderSize()) : NeededSize;
if (UNLIKELY(AlignedSize >= MaxAllowedMallocSize))
return FailureHandler::OnBadRequest();
@@ -403,7 +402,7 @@ struct ScudoAllocator {
BackendAllocator.getActuallyAllocatedSize(BackendPtr, ClassId));
UnpackedHeader Header = {};
- uptr UserPtr = reinterpret_cast<uptr>(BackendPtr) + AlignedChunkHeaderSize;
+ uptr UserPtr = reinterpret_cast<uptr>(BackendPtr) + Chunk::getHeaderSize();
if (UNLIKELY(!IsAligned(UserPtr, Alignment))) {
// Since the Secondary takes care of alignment, a non-aligned pointer
// means it is from the Primary. It is also the only case where the offset
@@ -505,7 +504,7 @@ struct ScudoAllocator {
}
}
}
- uptr Size = Header.ClassId ? Header.SizeOrUnusedBytes :
+ const uptr Size = Header.ClassId ? Header.SizeOrUnusedBytes :
Chunk::getUsableSize(Ptr, &Header) - Header.SizeOrUnusedBytes;
if (DeleteSizeMismatch) {
if (DeleteSize && DeleteSize != Size) {
Modified: compiler-rt/trunk/lib/scudo/scudo_allocator.h
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/scudo/scudo_allocator.h?rev=326206&r1=326205&r2=326206&view=diff
==============================================================================
--- compiler-rt/trunk/lib/scudo/scudo_allocator.h (original)
+++ compiler-rt/trunk/lib/scudo/scudo_allocator.h Tue Feb 27 08:14:49 2018
@@ -59,9 +59,17 @@ const uptr MaxAlignmentLog = 24; // 16
const uptr MinAlignment = 1 << MinAlignmentLog;
const uptr MaxAlignment = 1 << MaxAlignmentLog;
-const uptr ChunkHeaderSize = sizeof(PackedHeader);
-const uptr AlignedChunkHeaderSize =
- (ChunkHeaderSize + MinAlignment - 1) & ~(MinAlignment - 1);
+// constexpr version of __sanitizer::RoundUp without the extraneous CHECK.
+// This way we can use it in constexpr variables and functions declarations.
+constexpr uptr RoundUpTo(uptr Size, uptr Boundary) {
+ return (Size + Boundary - 1) & ~(Boundary - 1);
+}
+
+namespace Chunk {
+ constexpr uptr getHeaderSize() {
+ return RoundUpTo(sizeof(PackedHeader), MinAlignment);
+ }
+}
#if SANITIZER_CAN_USE_ALLOCATOR64
const uptr AllocatorSpace = ~0ULL;
@@ -97,11 +105,6 @@ struct AP32 {
typedef SizeClassAllocator32<AP32> PrimaryAllocator;
#endif // SANITIZER_CAN_USE_ALLOCATOR64
-// __sanitizer::RoundUp has a CHECK that is extraneous for us. Use our own.
-INLINE uptr RoundUpTo(uptr Size, uptr Boundary) {
- return (Size + Boundary - 1) & ~(Boundary - 1);
-}
-
#include "scudo_allocator_secondary.h"
#include "scudo_allocator_combined.h"
Modified: compiler-rt/trunk/lib/scudo/scudo_allocator_secondary.h
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/scudo/scudo_allocator_secondary.h?rev=326206&r1=326205&r2=326206&view=diff
==============================================================================
--- compiler-rt/trunk/lib/scudo/scudo_allocator_secondary.h (original)
+++ compiler-rt/trunk/lib/scudo/scudo_allocator_secondary.h Tue Feb 27 08:14:49 2018
@@ -28,7 +28,7 @@ class ScudoLargeMmapAllocator {
}
void *Allocate(AllocatorStats *Stats, uptr Size, uptr Alignment) {
- const uptr UserSize = Size - AlignedChunkHeaderSize;
+ const uptr UserSize = Size - Chunk::getHeaderSize();
// The Scudo frontend prevents us from allocating more than
// MaxAllowedMallocSize, so integer overflow checks would be superfluous.
uptr MapSize = Size + AlignedReservedAddressRangeSize;
@@ -80,7 +80,7 @@ class ScudoLargeMmapAllocator {
// Actually mmap the memory, preserving the guard pages on either side
CHECK_EQ(MapBeg + PageSize,
AddressRange.Map(MapBeg + PageSize, MapSize - 2 * PageSize));
- const uptr Ptr = UserBeg - AlignedChunkHeaderSize;
+ const uptr Ptr = UserBeg - Chunk::getHeaderSize();
ReservedAddressRange *StoredRange = getReservedAddressRange(Ptr);
*StoredRange = AddressRange;
@@ -129,9 +129,9 @@ class ScudoLargeMmapAllocator {
}
static constexpr uptr AlignedReservedAddressRangeSize =
- (sizeof(ReservedAddressRange) + MinAlignment - 1) & ~(MinAlignment - 1);
+ RoundUpTo(sizeof(ReservedAddressRange), MinAlignment);
static constexpr uptr HeadersSize =
- AlignedReservedAddressRangeSize + AlignedChunkHeaderSize;
+ AlignedReservedAddressRangeSize + Chunk::getHeaderSize();
uptr PageSizeCached;
SpinMutex StatsMutex;
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