/// ThisAllocated - This is true if this block is currently allocated. If
/// not, this can be converted to a FreeRangeHeader.
unsigned ThisAllocated : 1;
-
+
/// PrevAllocated - Keep track of whether the block immediately before us is
/// allocated. If not, the word immediately before this header is the size
/// of the previous block.
unsigned PrevAllocated : 1;
-
+
/// BlockSize - This is the size in bytes of this memory block,
/// including this header.
uintptr_t BlockSize : (sizeof(intptr_t)*CHAR_BIT - 2);
-
+
/// getBlockAfter - Return the memory block immediately after this one.
///
MemoryRangeHeader &getBlockAfter() const {
return *(MemoryRangeHeader*)((char*)this+BlockSize);
}
-
+
/// getFreeBlockBefore - If the block before this one is free, return it,
/// otherwise return null.
FreeRangeHeader *getFreeBlockBefore() const {
intptr_t PrevSize = ((intptr_t *)this)[-1];
return (FreeRangeHeader*)((char*)this-PrevSize);
}
-
+
/// FreeBlock - Turn an allocated block into a free block, adjusting
/// bits in the object headers, and adding an end of region memory block.
FreeRangeHeader *FreeBlock(FreeRangeHeader *FreeList);
-
+
/// TrimAllocationToSize - If this allocated block is significantly larger
/// than NewSize, split it into two pieces (where the former is NewSize
/// bytes, including the header), and add the new block to the free list.
- FreeRangeHeader *TrimAllocationToSize(FreeRangeHeader *FreeList,
+ FreeRangeHeader *TrimAllocationToSize(FreeRangeHeader *FreeList,
uint64_t NewSize);
};
struct FreeRangeHeader : public MemoryRangeHeader {
FreeRangeHeader *Prev;
FreeRangeHeader *Next;
-
+
/// getMinBlockSize - Get the minimum size for a memory block. Blocks
/// smaller than this size cannot be created.
static unsigned getMinBlockSize() {
return sizeof(FreeRangeHeader)+sizeof(intptr_t);
}
-
+
/// SetEndOfBlockSizeMarker - The word at the end of every free block is
/// known to be the size of the free block. Set it for this block.
void SetEndOfBlockSizeMarker() {
Next->Prev = Prev;
return Prev->Next = Next;
}
-
+
void AddToFreeList(FreeRangeHeader *FreeList) {
Next = FreeList;
Prev = FreeList->Prev;
/// GrowBlock - The block after this block just got deallocated. Merge it
/// into the current block.
void GrowBlock(uintptr_t NewSize);
-
+
/// AllocateBlock - Mark this entire block allocated, updating freelists
/// etc. This returns a pointer to the circular free-list.
FreeRangeHeader *AllocateBlock();
// Mark this block allocated.
ThisAllocated = 1;
getBlockAfter().PrevAllocated = 1;
-
+
// Remove it from the free list.
return RemoveFromFreeList();
}
MemoryRangeHeader *FollowingBlock = &getBlockAfter();
assert(ThisAllocated && "This block is already free!");
assert(FollowingBlock->PrevAllocated && "Flags out of sync!");
-
+
FreeRangeHeader *FreeListToReturn = FreeList;
-
+
// If the block after this one is free, merge it into this block.
if (!FollowingBlock->ThisAllocated) {
FreeRangeHeader &FollowingFreeBlock = *(FreeRangeHeader *)FollowingBlock;
assert(&FollowingFreeBlock != FreeList && "No tombstone block?");
}
FollowingFreeBlock.RemoveFromFreeList();
-
+
// Include the following block into this one.
BlockSize += FollowingFreeBlock.BlockSize;
FollowingBlock = &FollowingFreeBlock.getBlockAfter();
-
+
// Tell the block after the block we are coalescing that this block is
// allocated.
FollowingBlock->PrevAllocated = 1;
}
-
+
assert(FollowingBlock->ThisAllocated && "Missed coalescing?");
-
+
if (FreeRangeHeader *PrevFreeBlock = getFreeBlockBefore()) {
PrevFreeBlock->GrowBlock(PrevFreeBlock->BlockSize + BlockSize);
return FreeListToReturn ? FreeListToReturn : PrevFreeBlock;
// Round up size for alignment of header.
unsigned HeaderAlign = __alignof(FreeRangeHeader);
NewSize = (NewSize+ (HeaderAlign-1)) & ~(HeaderAlign-1);
-
+
// Size is now the size of the block we will remove from the start of the
// current block.
assert(NewSize <= BlockSize &&
"Allocating more space from this block than exists!");
-
+
// If splitting this block will cause the remainder to be too small, do not
// split the block.
if (BlockSize <= NewSize+FreeRangeHeader::getMinBlockSize())
return FreeList;
-
+
// Otherwise, we splice the required number of bytes out of this block, form
// a new block immediately after it, then mark this block allocated.
MemoryRangeHeader &FormerNextBlock = getBlockAfter();
-
+
// Change the size of this block.
BlockSize = NewSize;
-
+
// Get the new block we just sliced out and turn it into a free block.
FreeRangeHeader &NewNextBlock = (FreeRangeHeader &)getBlockAfter();
NewNextBlock.BlockSize = (char*)&FormerNextBlock - (char*)&NewNextBlock;
sys::MemoryBlock LastSlab;
// Memory slabs allocated by the JIT. We refer to them as slabs so we don't
- // confuse them with the blocks of memory descibed above.
+ // confuse them with the blocks of memory described above.
std::vector<sys::MemoryBlock> CodeSlabs;
JITSlabAllocator BumpSlabAllocator;
BumpPtrAllocator StubAllocator;
MemoryRangeHeader *CurBlock;
uint8_t *GOTBase; // Target Specific reserved memory
- void *DlsymTable; // Stub external symbol information
-
- std::map<const Function*, MemoryRangeHeader*> FunctionBlocks;
- std::map<const Function*, MemoryRangeHeader*> TableBlocks;
public:
DefaultJITMemoryManager();
~DefaultJITMemoryManager();
static const size_t DefaultSizeThreshold;
void AllocateGOT();
- void SetDlsymTable(void *);
// Testing methods.
virtual bool CheckInvariants(std::string &ErrorStr);
}
largest = largest - sizeof(MemoryRangeHeader);
-
+
// If this block isn't big enough for the allocation desired, allocate
// another block of memory and add it to the free list.
if (largest < ActualSize ||
largest <= FreeRangeHeader::getMinBlockSize()) {
- DOUT << "JIT: Allocating another slab of memory for function.";
+ DEBUG(dbgs() << "JIT: Allocating another slab of memory for function.");
candidateBlock = allocateNewCodeSlab((size_t)ActualSize);
}
"Mismatched function start/end!");
uintptr_t BlockSize = FunctionEnd - (uint8_t *)CurBlock;
- FunctionBlocks[F] = CurBlock;
// Release the memory at the end of this block that isn't needed.
FreeMemoryList =CurBlock->TrimAllocationToSize(FreeMemoryList, BlockSize);
return (uint8_t*)DataAllocator.Allocate(Size, Alignment);
}
- /// startExceptionTable - Use startFunctionBody to allocate memory for the
+ /// startExceptionTable - Use startFunctionBody to allocate memory for the
/// function's exception table.
uint8_t* startExceptionTable(const Function* F, uintptr_t &ActualSize) {
return startFunctionBody(F, ActualSize);
}
- /// endExceptionTable - The exception table of F is now allocated,
+ /// endExceptionTable - The exception table of F is now allocated,
/// and takes the memory in the range [TableStart,TableEnd).
void endExceptionTable(const Function *F, uint8_t *TableStart,
uint8_t *TableEnd, uint8_t* FrameRegister) {
assert(TableEnd > TableStart);
assert(TableStart == (uint8_t *)(CurBlock+1) &&
"Mismatched table start/end!");
-
+
uintptr_t BlockSize = TableEnd - (uint8_t *)CurBlock;
- TableBlocks[F] = CurBlock;
// Release the memory at the end of this block that isn't needed.
FreeMemoryList =CurBlock->TrimAllocationToSize(FreeMemoryList, BlockSize);
}
-
+
uint8_t *getGOTBase() const {
return GOTBase;
}
-
- void *getDlsymTable() const {
- return DlsymTable;
- }
-
- /// deallocateMemForFunction - Deallocate all memory for the specified
- /// function body.
- void deallocateMemForFunction(const Function *F) {
- std::map<const Function*, MemoryRangeHeader*>::iterator
- I = FunctionBlocks.find(F);
- if (I == FunctionBlocks.end()) return;
-
+
+ void deallocateBlock(void *Block) {
// Find the block that is allocated for this function.
- MemoryRangeHeader *MemRange = I->second;
+ MemoryRangeHeader *MemRange = static_cast<MemoryRangeHeader*>(Block) - 1;
assert(MemRange->ThisAllocated && "Block isn't allocated!");
// Fill the buffer with garbage!
// Free the memory.
FreeMemoryList = MemRange->FreeBlock(FreeMemoryList);
-
- // Finally, remove this entry from FunctionBlocks.
- FunctionBlocks.erase(I);
-
- I = TableBlocks.find(F);
- if (I == TableBlocks.end()) return;
-
- // Find the block that is allocated for this function.
- MemRange = I->second;
- assert(MemRange->ThisAllocated && "Block isn't allocated!");
+ }
- // Fill the buffer with garbage!
- if (PoisonMemory) {
- memset(MemRange+1, 0xCD, MemRange->BlockSize-sizeof(*MemRange));
- }
+ /// deallocateFunctionBody - Deallocate all memory for the specified
+ /// function body.
+ void deallocateFunctionBody(void *Body) {
+ if (Body) deallocateBlock(Body);
+ }
- // Free the memory.
- FreeMemoryList = MemRange->FreeBlock(FreeMemoryList);
-
- // Finally, remove this entry from TableBlocks.
- TableBlocks.erase(I);
+ /// deallocateExceptionTable - Deallocate memory for the specified
+ /// exception table.
+ void deallocateExceptionTable(void *ET) {
+ if (ET) deallocateBlock(ET);
}
/// setMemoryWritable - When code generation is in progress,
}
DefaultJITMemoryManager::DefaultJITMemoryManager()
- : LastSlab(0, 0),
- BumpSlabAllocator(*this),
- StubAllocator(DefaultSlabSize, DefaultSizeThreshold, BumpSlabAllocator),
- DataAllocator(DefaultSlabSize, DefaultSizeThreshold, BumpSlabAllocator) {
-
+ :
#ifdef NDEBUG
- PoisonMemory = false;
+ PoisonMemory(false),
#else
- PoisonMemory = true;
+ PoisonMemory(true),
#endif
+ LastSlab(0, 0),
+ BumpSlabAllocator(*this),
+ StubAllocator(DefaultSlabSize, DefaultSizeThreshold, BumpSlabAllocator),
+ DataAllocator(DefaultSlabSize, DefaultSizeThreshold, BumpSlabAllocator) {
// Allocate space for code.
sys::MemoryBlock MemBlock = allocateNewSlab(DefaultCodeSlabSize);
// END ]
//
// The last three blocks are never deallocated or touched.
-
+
// Add MemoryRangeHeader to the end of the memory region, indicating that
// the space after the block of memory is allocated. This is block #3.
MemoryRangeHeader *Mem3 = (MemoryRangeHeader*)(MemBase+MemBlock.size())-1;
Mem3->ThisAllocated = 1;
Mem3->PrevAllocated = 0;
Mem3->BlockSize = sizeof(MemoryRangeHeader);
-
+
/// Add a tiny free region so that the free list always has one entry.
- FreeRangeHeader *Mem2 =
+ FreeRangeHeader *Mem2 =
(FreeRangeHeader *)(((char*)Mem3)-FreeRangeHeader::getMinBlockSize());
Mem2->ThisAllocated = 0;
Mem2->PrevAllocated = 1;
Mem1->ThisAllocated = 1;
Mem1->PrevAllocated = 0;
Mem1->BlockSize = sizeof(MemoryRangeHeader);
-
+
// Add a FreeRangeHeader to the start of the function body region, indicating
// that the space is free. Mark the previous block allocated so we never look
// at it.
Mem0->BlockSize = (char*)Mem1-(char*)Mem0;
Mem0->SetEndOfBlockSizeMarker();
Mem0->AddToFreeList(Mem2);
-
+
// Start out with the freelist pointing to Mem0.
FreeMemoryList = Mem0;
GOTBase = NULL;
- DlsymTable = NULL;
}
void DefaultJITMemoryManager::AllocateGOT() {
HasGOT = true;
}
-void DefaultJITMemoryManager::SetDlsymTable(void *ptr) {
- DlsymTable = ptr;
-}
-
DefaultJITMemoryManager::~DefaultJITMemoryManager() {
for (unsigned i = 0, e = CodeSlabs.size(); i != e; ++i)
sys::Memory::ReleaseRWX(CodeSlabs[i]);
}
LastSlab = B;
++NumSlabs;
+ // Initialize the slab to garbage when debugging.
+ if (PoisonMemory) {
+ memset(B.base(), 0xCD, B.size());
+ }
return B;
}