skia2/include/core/SkChunkAlloc.h
milko.leporis 401e77cfe1 MIPS32r2: Fix Chromium runtime crash
Crash is caused by ldxc1 instruction, which traps when double values are
not aligned on 8-byte boundaries. Problem was tracked to SkChunkAlloc which
produces pointers aligned on 4-byte boundaries leading to misalignment.

This change makes sure that SkChunkAlloc will produce pointers that are
aligned to 8 bytes.

Appropriate tests are added to tests/MemsetTest.cpp

TEST=Build Chromium with Clang and run on MIPS32r2 platform
TEST=./out/Debug/dm --match Memset
BUG=130022
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1849183004

Review-Url: https://codereview.chromium.org/1849183004
2016-06-05 13:14:21 -07:00

90 lines
2.6 KiB
C++

/*
* Copyright 2006 The Android Open Source Project
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef SkChunkAlloc_DEFINED
#define SkChunkAlloc_DEFINED
#include "SkTypes.h"
class SkChunkAlloc : SkNoncopyable {
public:
SkChunkAlloc(size_t minSize);
~SkChunkAlloc();
/**
* Free up all allocated blocks. This invalidates all returned
* pointers.
*/
void reset();
/**
* Reset to 0 used bytes preserving as much memory as possible.
* This invalidates all returned pointers.
*/
void rewind();
enum AllocFailType {
kReturnNil_AllocFailType,
kThrow_AllocFailType
};
/**
* Allocates a memory block of size bytes.
* On success: returns a pointer to beginning of memory block that is
* 8 byte aligned. The content of allocated block is not initialized.
* On failure: calls abort() if called with kThrow_AllocFailType,
* otherwise returns NULL pointer.
*/
void* alloc(size_t bytes, AllocFailType);
/**
* Shortcut for calling alloc with kThrow_AllocFailType.
*/
void* allocThrow(size_t bytes) {
return this->alloc(bytes, kThrow_AllocFailType);
}
/** Call this to unalloc the most-recently allocated ptr by alloc(). On
success, the number of bytes freed is returned, or 0 if the block could
not be unallocated. This is a hint to the underlying allocator that
the previous allocation may be reused, but the implementation is free
to ignore this call (and return 0).
*/
size_t unalloc(void* ptr);
size_t totalCapacity() const { return fTotalCapacity; }
size_t totalUsed() const { return fTotalUsed; }
SkDEBUGCODE(int blockCount() const { return fBlockCount; })
SkDEBUGCODE(size_t totalLost() const { return fTotalLost; })
/**
* Returns true if the specified address is within one of the chunks, and
* has at least 1-byte following the address (i.e. if addr points to the
* end of a chunk, then contains() will return false).
*/
bool contains(const void* addr) const;
private:
struct Block;
Block* fBlock;
size_t fMinSize;
size_t fChunkSize;
size_t fTotalCapacity;
size_t fTotalUsed; // will be <= fTotalCapacity
SkDEBUGCODE(int fBlockCount;)
SkDEBUGCODE(size_t fTotalLost;) // will be <= fTotalCapacity
Block* newBlock(size_t bytes, AllocFailType ftype);
Block* addBlockIfNecessary(size_t bytes, AllocFailType ftype);
SkDEBUGCODE(void validate();)
};
#endif