//
//===----------------------------------------------------------------------===//
-#define DEBUG_TYPE "jit"
#include "llvm/ExecutionEngine/JITMemoryManager.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/Statistic.h"
-#include "llvm/GlobalValue.h"
+#include "llvm/ADT/Twine.h"
+#include "llvm/Config/config.h"
+#include "llvm/IR/GlobalValue.h"
#include "llvm/Support/Allocator.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/Debug.h"
+#include "llvm/Support/DynamicLibrary.h"
#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/Memory.h"
#include "llvm/Support/raw_ostream.h"
-#include "llvm/System/Memory.h"
-#include <map>
-#include <vector>
#include <cassert>
#include <climits>
-#include <cstdio>
-#include <cstdlib>
#include <cstring>
+#include <vector>
+
+#if defined(__linux__)
+#if defined(HAVE_SYS_STAT_H)
+#include <sys/stat.h>
+#endif
+#include <fcntl.h>
+#include <unistd.h>
+#endif
+
using namespace llvm;
+#define DEBUG_TYPE "jit"
+
STATISTIC(NumSlabs, "Number of slabs of memory allocated by the JIT");
JITMemoryManager::~JITMemoryManager() {}
/// 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);
+ return *reinterpret_cast<MemoryRangeHeader *>(
+ reinterpret_cast<char*>(
+ const_cast<MemoryRangeHeader *>(this))+BlockSize);
}
-
+
/// getFreeBlockBefore - If the block before this one is free, return it,
/// otherwise return null.
FreeRangeHeader *getFreeBlockBefore() const {
- if (PrevAllocated) return 0;
- intptr_t PrevSize = ((intptr_t *)this)[-1];
- return (FreeRangeHeader*)((char*)this-PrevSize);
+ if (PrevAllocated) return nullptr;
+ intptr_t PrevSize = reinterpret_cast<intptr_t *>(
+ const_cast<MemoryRangeHeader *>(this))[-1];
+ return reinterpret_cast<FreeRangeHeader *>(
+ reinterpret_cast<char*>(
+ const_cast<MemoryRangeHeader *>(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;
// coalesce with it, update our notion of what the free list is.
if (&FollowingFreeBlock == FreeList) {
FreeList = FollowingFreeBlock.Next;
- FreeListToReturn = 0;
+ FreeListToReturn = nullptr;
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;
class DefaultJITMemoryManager;
- class JITSlabAllocator : public SlabAllocator {
+ class JITAllocator {
DefaultJITMemoryManager &JMM;
public:
- JITSlabAllocator(DefaultJITMemoryManager &jmm) : JMM(jmm) { }
- virtual ~JITSlabAllocator() { }
- virtual MemSlab *Allocate(size_t Size);
- virtual void Deallocate(MemSlab *Slab);
+ JITAllocator(DefaultJITMemoryManager &jmm) : JMM(jmm) { }
+ void *Allocate(size_t Size, size_t /*Alignment*/);
+ void Deallocate(void *Slab, size_t Size);
};
/// DefaultJITMemoryManager - Manage memory for the JIT code generation.
/// middle of emitting a function, and we don't know how large the function we
/// are emitting is.
class DefaultJITMemoryManager : public JITMemoryManager {
+ public:
+ /// DefaultCodeSlabSize - When we have to go map more memory, we allocate at
+ /// least this much unless more is requested. Currently, in 512k slabs.
+ static const size_t DefaultCodeSlabSize = 512 * 1024;
+
+ /// DefaultSlabSize - Allocate globals and stubs into slabs of 64K (probably
+ /// 16 pages) unless we get an allocation above SizeThreshold.
+ static const size_t DefaultSlabSize = 64 * 1024;
+ /// DefaultSizeThreshold - For any allocation larger than 16K (probably
+ /// 4 pages), we should allocate a separate slab to avoid wasted space at
+ /// the end of a normal slab.
+ static const size_t DefaultSizeThreshold = 16 * 1024;
+
+ private:
// Whether to poison freed memory.
bool PoisonMemory;
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;
- BumpPtrAllocator DataAllocator;
+ BumpPtrAllocatorImpl<JITAllocator, DefaultSlabSize,
+ DefaultSizeThreshold> StubAllocator;
+ BumpPtrAllocatorImpl<JITAllocator, DefaultSlabSize,
+ DefaultSizeThreshold> DataAllocator;
// Circular list of free blocks.
FreeRangeHeader *FreeMemoryList;
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();
/// last slab it allocated, so that subsequent allocations follow it.
sys::MemoryBlock allocateNewSlab(size_t size);
- /// DefaultCodeSlabSize - When we have to go map more memory, we allocate at
- /// least this much unless more is requested.
- static const size_t DefaultCodeSlabSize;
-
- /// DefaultSlabSize - Allocate data into slabs of this size unless we get
- /// an allocation above SizeThreshold.
- static const size_t DefaultSlabSize;
+ /// getPointerToNamedFunction - This method returns the address of the
+ /// specified function by using the dlsym function call.
+ void *getPointerToNamedFunction(const std::string &Name,
+ bool AbortOnFailure = true) override;
- /// DefaultSizeThreshold - For any allocation larger than this threshold, we
- /// should allocate a separate slab.
- static const size_t DefaultSizeThreshold;
-
- void AllocateGOT();
- void SetDlsymTable(void *);
+ void AllocateGOT() override;
// Testing methods.
- virtual bool CheckInvariants(std::string &ErrorStr);
- size_t GetDefaultCodeSlabSize() { return DefaultCodeSlabSize; }
- size_t GetDefaultDataSlabSize() { return DefaultSlabSize; }
- size_t GetDefaultStubSlabSize() { return DefaultSlabSize; }
- unsigned GetNumCodeSlabs() { return CodeSlabs.size(); }
- unsigned GetNumDataSlabs() { return DataAllocator.GetNumSlabs(); }
- unsigned GetNumStubSlabs() { return StubAllocator.GetNumSlabs(); }
+ bool CheckInvariants(std::string &ErrorStr) override;
+ size_t GetDefaultCodeSlabSize() override { return DefaultCodeSlabSize; }
+ size_t GetDefaultDataSlabSize() override { return DefaultSlabSize; }
+ size_t GetDefaultStubSlabSize() override { return DefaultSlabSize; }
+ unsigned GetNumCodeSlabs() override { return CodeSlabs.size(); }
+ unsigned GetNumDataSlabs() override { return DataAllocator.GetNumSlabs(); }
+ unsigned GetNumStubSlabs() override { return StubAllocator.GetNumSlabs(); }
/// startFunctionBody - When a function starts, allocate a block of free
/// executable memory, returning a pointer to it and its actual size.
- uint8_t *startFunctionBody(const Function *F, uintptr_t &ActualSize) {
+ uint8_t *startFunctionBody(const Function *F,
+ uintptr_t &ActualSize) override {
FreeRangeHeader* candidateBlock = FreeMemoryList;
FreeRangeHeader* head = FreeMemoryList;
iter = iter->Next;
}
+ 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 - sizeof(MemoryRangeHeader) < ActualSize) {
- DOUT << "JIT: Allocating another slab of memory for function.";
+ if (largest < ActualSize ||
+ largest <= FreeRangeHeader::getMinBlockSize()) {
+ DEBUG(dbgs() << "JIT: Allocating another slab of memory for function.");
candidateBlock = allocateNewCodeSlab((size_t)ActualSize);
}
/// endFunctionBody - The function F is now allocated, and takes the memory
/// in the range [FunctionStart,FunctionEnd).
void endFunctionBody(const Function *F, uint8_t *FunctionStart,
- uint8_t *FunctionEnd) {
+ uint8_t *FunctionEnd) override {
assert(FunctionEnd > FunctionStart);
assert(FunctionStart == (uint8_t *)(CurBlock+1) &&
"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);
/// allocateSpace - Allocate a memory block of the given size. This method
/// cannot be called between calls to startFunctionBody and endFunctionBody.
- uint8_t *allocateSpace(intptr_t Size, unsigned Alignment) {
+ uint8_t *allocateSpace(intptr_t Size, unsigned Alignment) override {
CurBlock = FreeMemoryList;
FreeMemoryList = FreeMemoryList->AllocateBlock();
/// allocateStub - Allocate memory for a function stub.
uint8_t *allocateStub(const GlobalValue* F, unsigned StubSize,
- unsigned Alignment) {
+ unsigned Alignment) override {
return (uint8_t*)StubAllocator.Allocate(StubSize, Alignment);
}
/// allocateGlobal - Allocate memory for a global.
- uint8_t *allocateGlobal(uintptr_t Size, unsigned Alignment) {
+ uint8_t *allocateGlobal(uintptr_t Size, unsigned Alignment) override {
return (uint8_t*)DataAllocator.Allocate(Size, Alignment);
}
- /// 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);
- }
+ /// allocateCodeSection - Allocate memory for a code section.
+ uint8_t *allocateCodeSection(uintptr_t Size, unsigned Alignment,
+ unsigned SectionID,
+ StringRef SectionName) override {
+ // Grow the required block size to account for the block header
+ Size += sizeof(*CurBlock);
+
+ // Alignment handling.
+ if (!Alignment)
+ Alignment = 16;
+ Size += Alignment - 1;
+
+ FreeRangeHeader* candidateBlock = FreeMemoryList;
+ FreeRangeHeader* head = FreeMemoryList;
+ FreeRangeHeader* iter = head->Next;
+
+ uintptr_t largest = candidateBlock->BlockSize;
- /// 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;
+ // Search for the largest free block.
+ while (iter != head) {
+ if (iter->BlockSize > largest) {
+ largest = iter->BlockSize;
+ candidateBlock = iter;
+ }
+ iter = iter->Next;
+ }
+
+ 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 < Size || largest <= FreeRangeHeader::getMinBlockSize()) {
+ DEBUG(dbgs() << "JIT: Allocating another slab of memory for function.");
+ candidateBlock = allocateNewCodeSlab((size_t)Size);
+ }
+
+ // Select this candidate block for allocation
+ CurBlock = candidateBlock;
+ // Allocate the entire memory block.
+ FreeMemoryList = candidateBlock->AllocateBlock();
// Release the memory at the end of this block that isn't needed.
- FreeMemoryList =CurBlock->TrimAllocationToSize(FreeMemoryList, BlockSize);
+ FreeMemoryList = CurBlock->TrimAllocationToSize(FreeMemoryList, Size);
+ uintptr_t unalignedAddr = (uintptr_t)CurBlock + sizeof(*CurBlock);
+ return (uint8_t*)RoundUpToAlignment((uint64_t)unalignedAddr, Alignment);
}
-
- uint8_t *getGOTBase() const {
- return GOTBase;
+
+ /// allocateDataSection - Allocate memory for a data section.
+ uint8_t *allocateDataSection(uintptr_t Size, unsigned Alignment,
+ unsigned SectionID, StringRef SectionName,
+ bool IsReadOnly) override {
+ return (uint8_t*)DataAllocator.Allocate(Size, Alignment);
}
-
- void *getDlsymTable() const {
- return DlsymTable;
+
+ bool finalizeMemory(std::string *ErrMsg) override {
+ return false;
}
-
- /// 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;
-
- // Find the block that is allocated for this function.
- MemoryRangeHeader *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));
- }
+ uint8_t *getGOTBase() const override {
+ return GOTBase;
+ }
- // 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;
-
+ void deallocateBlock(void *Block) {
// Find the block that is allocated for this function.
- 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 TableBlocks.
- TableBlocks.erase(I);
+ }
+
+ /// deallocateFunctionBody - Deallocate all memory for the specified
+ /// function body.
+ void deallocateFunctionBody(void *Body) override {
+ if (Body) deallocateBlock(Body);
}
/// setMemoryWritable - When code generation is in progress,
/// the code pages may need permissions changed.
- void setMemoryWritable(void)
- {
+ void setMemoryWritable() override {
for (unsigned i = 0, e = CodeSlabs.size(); i != e; ++i)
sys::Memory::setWritable(CodeSlabs[i]);
}
/// setMemoryExecutable - When code generation is done and we're ready to
/// start execution, the code pages may need permissions changed.
- void setMemoryExecutable(void)
- {
+ void setMemoryExecutable() override {
for (unsigned i = 0, e = CodeSlabs.size(); i != e; ++i)
sys::Memory::setExecutable(CodeSlabs[i]);
}
/// setPoisonMemory - Controls whether we write garbage over freed memory.
///
- void setPoisonMemory(bool poison) {
+ void setPoisonMemory(bool poison) override {
PoisonMemory = poison;
}
};
}
-MemSlab *JITSlabAllocator::Allocate(size_t Size) {
+void *JITAllocator::Allocate(size_t Size, size_t /*Alignment*/) {
sys::MemoryBlock B = JMM.allocateNewSlab(Size);
- MemSlab *Slab = (MemSlab*)B.base();
- Slab->Size = B.size();
- Slab->NextPtr = 0;
- return Slab;
+ return B.base();
}
-void JITSlabAllocator::Deallocate(MemSlab *Slab) {
- sys::MemoryBlock B(Slab, Slab->Size);
+void JITAllocator::Deallocate(void *Slab, size_t Size) {
+ sys::MemoryBlock B(Slab, Size);
sys::Memory::ReleaseRWX(B);
}
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(nullptr, 0), StubAllocator(*this), DataAllocator(*this) {
// 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;
+ GOTBase = nullptr;
}
void DefaultJITMemoryManager::AllocateGOT() {
- assert(GOTBase == 0 && "Cannot allocate the got multiple times");
+ assert(!GOTBase && "Cannot allocate the got multiple times");
GOTBase = new uint8_t[sizeof(void*) * 8192];
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]);
sys::MemoryBlock DefaultJITMemoryManager::allocateNewSlab(size_t size) {
// Allocate a new block close to the last one.
std::string ErrMsg;
- sys::MemoryBlock *LastSlabPtr = LastSlab.base() ? &LastSlab : 0;
+ sys::MemoryBlock *LastSlabPtr = LastSlab.base() ? &LastSlab : nullptr;
sys::MemoryBlock B = sys::Memory::AllocateRWX(size, LastSlabPtr, &ErrMsg);
- if (B.base() == 0) {
- llvm_report_error("Allocation failed when allocating new memory in the"
- " JIT\n" + ErrMsg);
+ if (!B.base()) {
+ report_fatal_error("Allocation failed when allocating new memory in the"
+ " JIT\n" + Twine(ErrMsg));
}
LastSlab = B;
++NumSlabs;
+ // Initialize the slab to garbage when debugging.
+ if (PoisonMemory) {
+ memset(B.base(), 0xCD, B.size());
+ }
return B;
}
char *End = Start + I->size();
// Check each memory range.
- for (MemoryRangeHeader *Hdr = (MemoryRangeHeader*)Start, *LastHdr = NULL;
+ for (MemoryRangeHeader *Hdr = (MemoryRangeHeader*)Start, *LastHdr = nullptr;
Start <= (char*)Hdr && (char*)Hdr < End;
Hdr = &Hdr->getBlockAfter()) {
if (Hdr->ThisAllocated == 0) {
return true;
}
-JITMemoryManager *JITMemoryManager::CreateDefaultMemManager() {
- return new DefaultJITMemoryManager();
+//===----------------------------------------------------------------------===//
+// getPointerToNamedFunction() implementation.
+//===----------------------------------------------------------------------===//
+
+// AtExitHandlers - List of functions to call when the program exits,
+// registered with the atexit() library function.
+static std::vector<void (*)()> AtExitHandlers;
+
+/// runAtExitHandlers - Run any functions registered by the program's
+/// calls to atexit(3), which we intercept and store in
+/// AtExitHandlers.
+///
+static void runAtExitHandlers() {
+ while (!AtExitHandlers.empty()) {
+ void (*Fn)() = AtExitHandlers.back();
+ AtExitHandlers.pop_back();
+ Fn();
+ }
+}
+
+//===----------------------------------------------------------------------===//
+// Function stubs that are invoked instead of certain library calls
+//
+// Force the following functions to be linked in to anything that uses the
+// JIT. This is a hack designed to work around the all-too-clever Glibc
+// strategy of making these functions work differently when inlined vs. when
+// not inlined, and hiding their real definitions in a separate archive file
+// that the dynamic linker can't see. For more info, search for
+// 'libc_nonshared.a' on Google, or read http://llvm.org/PR274.
+#if defined(__linux__) && defined(__GLIBC__)
+/* stat functions are redirecting to __xstat with a version number. On x86-64
+ * linking with libc_nonshared.a and -Wl,--export-dynamic doesn't make 'stat'
+ * available as an exported symbol, so we have to add it explicitly.
+ */
+namespace {
+class StatSymbols {
+public:
+ StatSymbols() {
+ sys::DynamicLibrary::AddSymbol("stat", (void*)(intptr_t)stat);
+ sys::DynamicLibrary::AddSymbol("fstat", (void*)(intptr_t)fstat);
+ sys::DynamicLibrary::AddSymbol("lstat", (void*)(intptr_t)lstat);
+ sys::DynamicLibrary::AddSymbol("stat64", (void*)(intptr_t)stat64);
+ sys::DynamicLibrary::AddSymbol("\x1stat64", (void*)(intptr_t)stat64);
+ sys::DynamicLibrary::AddSymbol("\x1open64", (void*)(intptr_t)open64);
+ sys::DynamicLibrary::AddSymbol("\x1lseek64", (void*)(intptr_t)lseek64);
+ sys::DynamicLibrary::AddSymbol("fstat64", (void*)(intptr_t)fstat64);
+ sys::DynamicLibrary::AddSymbol("lstat64", (void*)(intptr_t)lstat64);
+ sys::DynamicLibrary::AddSymbol("atexit", (void*)(intptr_t)atexit);
+ sys::DynamicLibrary::AddSymbol("mknod", (void*)(intptr_t)mknod);
+ }
+};
+}
+static StatSymbols initStatSymbols;
+#endif // __linux__
+
+// jit_exit - Used to intercept the "exit" library call.
+static void jit_exit(int Status) {
+ runAtExitHandlers(); // Run atexit handlers...
+ exit(Status);
+}
+
+// jit_atexit - Used to intercept the "atexit" library call.
+static int jit_atexit(void (*Fn)()) {
+ AtExitHandlers.push_back(Fn); // Take note of atexit handler...
+ return 0; // Always successful
}
-// Allocate memory for code in 512K slabs.
-const size_t DefaultJITMemoryManager::DefaultCodeSlabSize = 512 * 1024;
+static int jit_noop() {
+ return 0;
+}
-// Allocate globals and stubs in slabs of 64K. (probably 16 pages)
-const size_t DefaultJITMemoryManager::DefaultSlabSize = 64 * 1024;
+//===----------------------------------------------------------------------===//
+//
+/// getPointerToNamedFunction - This method returns the address of the specified
+/// function by using the dynamic loader interface. As such it is only useful
+/// for resolving library symbols, not code generated symbols.
+///
+void *DefaultJITMemoryManager::getPointerToNamedFunction(const std::string &Name,
+ bool AbortOnFailure) {
+ // Check to see if this is one of the functions we want to intercept. Note,
+ // we cast to intptr_t here to silence a -pedantic warning that complains
+ // about casting a function pointer to a normal pointer.
+ if (Name == "exit") return (void*)(intptr_t)&jit_exit;
+ if (Name == "atexit") return (void*)(intptr_t)&jit_atexit;
+
+ // We should not invoke parent's ctors/dtors from generated main()!
+ // On Mingw and Cygwin, the symbol __main is resolved to
+ // callee's(eg. tools/lli) one, to invoke wrong duplicated ctors
+ // (and register wrong callee's dtors with atexit(3)).
+ // We expect ExecutionEngine::runStaticConstructorsDestructors()
+ // is called before ExecutionEngine::runFunctionAsMain() is called.
+ if (Name == "__main") return (void*)(intptr_t)&jit_noop;
+
+ const char *NameStr = Name.c_str();
+ // If this is an asm specifier, skip the sentinal.
+ if (NameStr[0] == 1) ++NameStr;
+
+ // If it's an external function, look it up in the process image...
+ void *Ptr = sys::DynamicLibrary::SearchForAddressOfSymbol(NameStr);
+ if (Ptr) return Ptr;
+
+ // If it wasn't found and if it starts with an underscore ('_') character,
+ // try again without the underscore.
+ if (NameStr[0] == '_') {
+ Ptr = sys::DynamicLibrary::SearchForAddressOfSymbol(NameStr+1);
+ if (Ptr) return Ptr;
+ }
+
+ // Darwin/PPC adds $LDBLStub suffixes to various symbols like printf. These
+ // are references to hidden visibility symbols that dlsym cannot resolve.
+ // If we have one of these, strip off $LDBLStub and try again.
+#if defined(__APPLE__) && defined(__ppc__)
+ if (Name.size() > 9 && Name[Name.size()-9] == '$' &&
+ memcmp(&Name[Name.size()-8], "LDBLStub", 8) == 0) {
+ // First try turning $LDBLStub into $LDBL128. If that fails, strip it off.
+ // This mirrors logic in libSystemStubs.a.
+ std::string Prefix = std::string(Name.begin(), Name.end()-9);
+ if (void *Ptr = getPointerToNamedFunction(Prefix+"$LDBL128", false))
+ return Ptr;
+ if (void *Ptr = getPointerToNamedFunction(Prefix, false))
+ return Ptr;
+ }
+#endif
+
+ if (AbortOnFailure) {
+ report_fatal_error("Program used external function '"+Name+
+ "' which could not be resolved!");
+ }
+ return nullptr;
+}
+
+
+
+JITMemoryManager *JITMemoryManager::CreateDefaultMemManager() {
+ return new DefaultJITMemoryManager();
+}
-// Waste at most 16K at the end of each bump slab. (probably 4 pages)
-const size_t DefaultJITMemoryManager::DefaultSizeThreshold = 16 * 1024;
+const size_t DefaultJITMemoryManager::DefaultCodeSlabSize;
+const size_t DefaultJITMemoryManager::DefaultSlabSize;
+const size_t DefaultJITMemoryManager::DefaultSizeThreshold;
projects / oota-llvm.git / blobdiff