mirror of
https://github.com/c64scene-ar/llvm-6502.git
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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22568 91177308-0d34-0410-b5e6-96231b3b80d8
646 lines
23 KiB
C++
646 lines
23 KiB
C++
//===-- JITEmitter.cpp - Write machine code to executable memory ----------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file was developed by the LLVM research group and is distributed under
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// the University of Illinois Open Source License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This file defines a MachineCodeEmitter object that is used by the JIT to
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// write machine code to memory and remember where relocatable values are.
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//
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//===----------------------------------------------------------------------===//
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#define DEBUG_TYPE "jit"
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#include "JIT.h"
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#include "llvm/Constant.h"
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#include "llvm/Module.h"
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#include "llvm/Type.h"
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#include "llvm/CodeGen/MachineCodeEmitter.h"
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#include "llvm/CodeGen/MachineFunction.h"
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#include "llvm/CodeGen/MachineConstantPool.h"
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#include "llvm/CodeGen/MachineRelocation.h"
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#include "llvm/Target/TargetData.h"
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#include "llvm/Target/TargetJITInfo.h"
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#include "llvm/Support/Debug.h"
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#include "llvm/ADT/Statistic.h"
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#include "llvm/System/Memory.h"
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#include <list>
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#include <algorithm>
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using namespace llvm;
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namespace {
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Statistic<> NumBytes("jit", "Number of bytes of machine code compiled");
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Statistic<> NumRelos("jit", "Number of relocations applied");
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JIT *TheJIT = 0;
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}
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//===----------------------------------------------------------------------===//
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// JITMemoryManager code.
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//
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namespace {
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/// JITMemoryManager - Manage memory for the JIT code generation in a logical,
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/// sane way. This splits a large block of MAP_NORESERVE'd memory into two
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/// sections, one for function stubs, one for the functions themselves. We
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/// have to do this because we may need to emit a function stub while in the
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/// middle of emitting a function, and we don't know how large the function we
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/// are emitting is. This never bothers to release the memory, because when
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/// we are ready to destroy the JIT, the program exits.
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class JITMemoryManager {
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std::list<sys::MemoryBlock> Blocks; // List of blocks allocated by the JIT
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unsigned char *FunctionBase; // Start of the function body area
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unsigned char *GlobalBase; // Start of the Global area
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unsigned char *ConstantBase; // Memory allocated for constant pools
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unsigned char *CurStubPtr, *CurFunctionPtr, *CurConstantPtr, *CurGlobalPtr;
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unsigned char *GOTBase; //Target Specific reserved memory
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// centralize memory block allocation
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sys::MemoryBlock getNewMemoryBlock(unsigned size);
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public:
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JITMemoryManager(bool useGOT);
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~JITMemoryManager();
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inline unsigned char *allocateStub(unsigned StubSize);
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inline unsigned char *allocateConstant(unsigned ConstantSize,
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unsigned Alignment);
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inline unsigned char* allocateGlobal(unsigned Size,
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unsigned Alignment);
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inline unsigned char *startFunctionBody();
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inline void endFunctionBody(unsigned char *FunctionEnd);
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inline unsigned char* getGOTBase() const;
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inline bool isManagingGOT() const;
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};
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}
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JITMemoryManager::JITMemoryManager(bool useGOT) {
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// Allocate a 16M block of memory for functions
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sys::MemoryBlock FunBlock = getNewMemoryBlock(16 << 20);
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// Allocate a 1M block of memory for Constants
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sys::MemoryBlock ConstBlock = getNewMemoryBlock(1 << 20);
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// Allocate a 1M Block of memory for Globals
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sys::MemoryBlock GVBlock = getNewMemoryBlock(1 << 20);
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Blocks.push_front(FunBlock);
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Blocks.push_front(ConstBlock);
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Blocks.push_front(GVBlock);
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FunctionBase = reinterpret_cast<unsigned char*>(FunBlock.base());
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ConstantBase = reinterpret_cast<unsigned char*>(ConstBlock.base());
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GlobalBase = reinterpret_cast<unsigned char*>(GVBlock.base());
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// Allocate stubs backwards from the base, allocate functions forward
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// from the base.
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CurStubPtr = CurFunctionPtr = FunctionBase + 512*1024;// Use 512k for stubs
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CurConstantPtr = ConstantBase + ConstBlock.size();
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CurGlobalPtr = GlobalBase + GVBlock.size();
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//Allocate the GOT just like a global array
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GOTBase = NULL;
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if (useGOT)
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GOTBase = allocateGlobal(sizeof(void*) * 8192, 8);
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}
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JITMemoryManager::~JITMemoryManager() {
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for (std::list<sys::MemoryBlock>::iterator ib = Blocks.begin(), ie = Blocks.end();
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ib != ie; ++ib)
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sys::Memory::ReleaseRWX(*ib);
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Blocks.clear();
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}
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unsigned char *JITMemoryManager::allocateStub(unsigned StubSize) {
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CurStubPtr -= StubSize;
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if (CurStubPtr < FunctionBase) {
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//FIXME: allocate a new block
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std::cerr << "JIT ran out of memory for function stubs!\n";
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abort();
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}
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return CurStubPtr;
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}
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unsigned char *JITMemoryManager::allocateConstant(unsigned ConstantSize,
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unsigned Alignment) {
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// Reserve space and align pointer.
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CurConstantPtr -= ConstantSize;
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CurConstantPtr =
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(unsigned char *)((intptr_t)CurConstantPtr & ~((intptr_t)Alignment - 1));
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if (CurConstantPtr < ConstantBase) {
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//Either allocate another MB or 2xConstantSize
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sys::MemoryBlock ConstBlock = getNewMemoryBlock(2 * ConstantSize);
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ConstantBase = reinterpret_cast<unsigned char*>(ConstBlock.base());
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CurConstantPtr = ConstantBase + ConstBlock.size();
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return allocateConstant(ConstantSize, Alignment);
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}
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return CurConstantPtr;
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}
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unsigned char *JITMemoryManager::allocateGlobal(unsigned Size,
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unsigned Alignment) {
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// Reserve space and align pointer.
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CurGlobalPtr -= Size;
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CurGlobalPtr =
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(unsigned char *)((intptr_t)CurGlobalPtr & ~((intptr_t)Alignment - 1));
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if (CurGlobalPtr < GlobalBase) {
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//Either allocate another MB or 2xSize
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sys::MemoryBlock GVBlock = getNewMemoryBlock(2 * Size);
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GlobalBase = reinterpret_cast<unsigned char*>(GVBlock.base());
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CurGlobalPtr = GlobalBase + GVBlock.size();
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return allocateGlobal(Size, Alignment);
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}
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return CurGlobalPtr;
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}
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unsigned char *JITMemoryManager::startFunctionBody() {
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// Round up to an even multiple of 8 bytes, this should eventually be target
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// specific.
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return (unsigned char*)(((intptr_t)CurFunctionPtr + 7) & ~7);
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}
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void JITMemoryManager::endFunctionBody(unsigned char *FunctionEnd) {
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assert(FunctionEnd > CurFunctionPtr);
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CurFunctionPtr = FunctionEnd;
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}
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unsigned char* JITMemoryManager::getGOTBase() const {
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return GOTBase;
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}
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bool JITMemoryManager::isManagingGOT() const {
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return GOTBase != NULL;
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}
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sys::MemoryBlock JITMemoryManager::getNewMemoryBlock(unsigned size) {
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const sys::MemoryBlock* BOld = 0;
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if (Blocks.size())
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BOld = &Blocks.front();
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//never allocate less than 1 MB
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sys::MemoryBlock B;
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try {
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B = sys::Memory::AllocateRWX(std::max(((unsigned)1 << 20), size), BOld);
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} catch (std::string& err) {
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std::cerr << "Allocation failed when allocating new memory in the JIT\n";
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std::cerr << err << "\n";
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abort();
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}
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Blocks.push_front(B);
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return B;
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}
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//===----------------------------------------------------------------------===//
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// JIT lazy compilation code.
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//
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namespace {
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class JITResolverState {
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private:
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/// FunctionToStubMap - Keep track of the stub created for a particular
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/// function so that we can reuse them if necessary.
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std::map<Function*, void*> FunctionToStubMap;
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/// StubToFunctionMap - Keep track of the function that each stub
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/// corresponds to.
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std::map<void*, Function*> StubToFunctionMap;
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public:
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std::map<Function*, void*>& getFunctionToStubMap(const MutexGuard& locked) {
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assert(locked.holds(TheJIT->lock));
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return FunctionToStubMap;
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}
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std::map<void*, Function*>& getStubToFunctionMap(const MutexGuard& locked) {
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assert(locked.holds(TheJIT->lock));
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return StubToFunctionMap;
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}
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};
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/// JITResolver - Keep track of, and resolve, call sites for functions that
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/// have not yet been compiled.
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class JITResolver {
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/// MCE - The MachineCodeEmitter to use to emit stubs with.
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MachineCodeEmitter &MCE;
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/// LazyResolverFn - The target lazy resolver function that we actually
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/// rewrite instructions to use.
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TargetJITInfo::LazyResolverFn LazyResolverFn;
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JITResolverState state;
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/// ExternalFnToStubMap - This is the equivalent of FunctionToStubMap for
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/// external functions.
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std::map<void*, void*> ExternalFnToStubMap;
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//map addresses to indexes in the GOT
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std::map<void*, unsigned> revGOTMap;
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unsigned nextGOTIndex;
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public:
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JITResolver(MachineCodeEmitter &mce) : MCE(mce), nextGOTIndex(0) {
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LazyResolverFn =
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TheJIT->getJITInfo().getLazyResolverFunction(JITCompilerFn);
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}
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/// getFunctionStub - This returns a pointer to a function stub, creating
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/// one on demand as needed.
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void *getFunctionStub(Function *F);
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/// getExternalFunctionStub - Return a stub for the function at the
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/// specified address, created lazily on demand.
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void *getExternalFunctionStub(void *FnAddr);
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/// AddCallbackAtLocation - If the target is capable of rewriting an
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/// instruction without the use of a stub, record the location of the use so
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/// we know which function is being used at the location.
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void *AddCallbackAtLocation(Function *F, void *Location) {
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MutexGuard locked(TheJIT->lock);
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/// Get the target-specific JIT resolver function.
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state.getStubToFunctionMap(locked)[Location] = F;
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return (void*)LazyResolverFn;
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}
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/// getGOTIndexForAddress - Return a new or existing index in the GOT for
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/// and address. This function only manages slots, it does not manage the
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/// contents of the slots or the memory associated with the GOT.
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unsigned getGOTIndexForAddr(void* addr);
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/// JITCompilerFn - This function is called to resolve a stub to a compiled
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/// address. If the LLVM Function corresponding to the stub has not yet
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/// been compiled, this function compiles it first.
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static void *JITCompilerFn(void *Stub);
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};
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}
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/// getJITResolver - This function returns the one instance of the JIT resolver.
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///
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static JITResolver &getJITResolver(MachineCodeEmitter *MCE = 0) {
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static JITResolver TheJITResolver(*MCE);
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return TheJITResolver;
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}
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/// getFunctionStub - This returns a pointer to a function stub, creating
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/// one on demand as needed.
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void *JITResolver::getFunctionStub(Function *F) {
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MutexGuard locked(TheJIT->lock);
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// If we already have a stub for this function, recycle it.
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void *&Stub = state.getFunctionToStubMap(locked)[F];
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if (Stub) return Stub;
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// Call the lazy resolver function unless we already KNOW it is an external
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// function, in which case we just skip the lazy resolution step.
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void *Actual = (void*)LazyResolverFn;
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if (F->isExternal() && F->hasExternalLinkage())
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Actual = TheJIT->getPointerToFunction(F);
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// Otherwise, codegen a new stub. For now, the stub will call the lazy
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// resolver function.
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Stub = TheJIT->getJITInfo().emitFunctionStub(Actual, MCE);
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if (Actual != (void*)LazyResolverFn) {
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// If we are getting the stub for an external function, we really want the
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// address of the stub in the GlobalAddressMap for the JIT, not the address
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// of the external function.
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TheJIT->updateGlobalMapping(F, Stub);
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}
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DEBUG(std::cerr << "JIT: Stub emitted at [" << Stub << "] for function '"
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<< F->getName() << "'\n");
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// Finally, keep track of the stub-to-Function mapping so that the
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// JITCompilerFn knows which function to compile!
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state.getStubToFunctionMap(locked)[Stub] = F;
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return Stub;
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}
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/// getExternalFunctionStub - Return a stub for the function at the
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/// specified address, created lazily on demand.
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void *JITResolver::getExternalFunctionStub(void *FnAddr) {
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// If we already have a stub for this function, recycle it.
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void *&Stub = ExternalFnToStubMap[FnAddr];
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if (Stub) return Stub;
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Stub = TheJIT->getJITInfo().emitFunctionStub(FnAddr, MCE);
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DEBUG(std::cerr << "JIT: Stub emitted at [" << Stub
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<< "] for external function at '" << FnAddr << "'\n");
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return Stub;
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}
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unsigned JITResolver::getGOTIndexForAddr(void* addr) {
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unsigned idx = revGOTMap[addr];
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if (!idx) {
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idx = ++nextGOTIndex;
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revGOTMap[addr] = idx;
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DEBUG(std::cerr << "Adding GOT entry " << idx
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<< " for addr " << addr << "\n");
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// ((void**)MemMgr.getGOTBase())[idx] = addr;
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}
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return idx;
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}
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/// JITCompilerFn - This function is called when a lazy compilation stub has
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/// been entered. It looks up which function this stub corresponds to, compiles
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/// it if necessary, then returns the resultant function pointer.
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void *JITResolver::JITCompilerFn(void *Stub) {
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JITResolver &JR = getJITResolver();
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MutexGuard locked(TheJIT->lock);
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// The address given to us for the stub may not be exactly right, it might be
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// a little bit after the stub. As such, use upper_bound to find it.
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std::map<void*, Function*>::iterator I =
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JR.state.getStubToFunctionMap(locked).upper_bound(Stub);
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assert(I != JR.state.getStubToFunctionMap(locked).begin() && "This is not a known stub!");
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Function *F = (--I)->second;
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// We might like to remove the stub from the StubToFunction map.
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// We can't do that! Multiple threads could be stuck, waiting to acquire the
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// lock above. As soon as the 1st function finishes compiling the function,
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// the next one will be released, and needs to be able to find the function it needs
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// to call.
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//JR.state.getStubToFunctionMap(locked).erase(I);
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DEBUG(std::cerr << "JIT: Lazily resolving function '" << F->getName()
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<< "' In stub ptr = " << Stub << " actual ptr = "
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<< I->first << "\n");
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void *Result = TheJIT->getPointerToFunction(F);
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// We don't need to reuse this stub in the future, as F is now compiled.
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JR.state.getFunctionToStubMap(locked).erase(F);
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// FIXME: We could rewrite all references to this stub if we knew them.
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// What we will do is set the compiled function address to map to the
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// same GOT entry as the stub so that later clients may update the GOT
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// if they see it still using the stub address.
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// Note: this is done so the Resolver doesn't have to manage GOT memory
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// Do this without allocating map space if the target isn't using a GOT
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if(JR.revGOTMap.find(Stub) != JR.revGOTMap.end())
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JR.revGOTMap[Result] = JR.revGOTMap[Stub];
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return Result;
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}
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// getPointerToFunctionOrStub - If the specified function has been
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// code-gen'd, return a pointer to the function. If not, compile it, or use
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// a stub to implement lazy compilation if available.
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//
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void *JIT::getPointerToFunctionOrStub(Function *F) {
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// If we have already code generated the function, just return the address.
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if (void *Addr = getPointerToGlobalIfAvailable(F))
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return Addr;
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// Get a stub if the target supports it
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return getJITResolver(MCE).getFunctionStub(F);
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}
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//===----------------------------------------------------------------------===//
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// JITEmitter code.
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//
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namespace {
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/// JITEmitter - The JIT implementation of the MachineCodeEmitter, which is
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/// used to output functions to memory for execution.
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class JITEmitter : public MachineCodeEmitter {
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JITMemoryManager MemMgr;
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// CurBlock - The start of the current block of memory. CurByte - The
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// current byte being emitted to.
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unsigned char *CurBlock, *CurByte;
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// When outputting a function stub in the context of some other function, we
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// save CurBlock and CurByte here.
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unsigned char *SavedCurBlock, *SavedCurByte;
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// ConstantPoolAddresses - Contains the location for each entry in the
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// constant pool.
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std::vector<void*> ConstantPoolAddresses;
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/// Relocations - These are the relocations that the function needs, as
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/// emitted.
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std::vector<MachineRelocation> Relocations;
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public:
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JITEmitter(JIT &jit)
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:MemMgr(jit.getJITInfo().needsGOT())
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{
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TheJIT = &jit;
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DEBUG(std::cerr <<
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(MemMgr.isManagingGOT() ? "JIT is managing GOT\n"
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: "JIT is not managing GOT\n"));
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}
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virtual void startFunction(MachineFunction &F);
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virtual void finishFunction(MachineFunction &F);
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virtual void emitConstantPool(MachineConstantPool *MCP);
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virtual void startFunctionStub(unsigned StubSize);
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virtual void* finishFunctionStub(const Function *F);
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virtual void emitByte(unsigned char B);
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virtual void emitWord(unsigned W);
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virtual void emitWordAt(unsigned W, unsigned *Ptr);
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virtual void addRelocation(const MachineRelocation &MR) {
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Relocations.push_back(MR);
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}
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virtual uint64_t getCurrentPCValue();
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virtual uint64_t getCurrentPCOffset();
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virtual uint64_t getConstantPoolEntryAddress(unsigned Entry);
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virtual unsigned char* allocateGlobal(unsigned size, unsigned alignment);
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private:
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void *getPointerToGlobal(GlobalValue *GV, void *Reference, bool NoNeedStub);
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};
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}
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MachineCodeEmitter *JIT::createEmitter(JIT &jit) {
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return new JITEmitter(jit);
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}
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void *JITEmitter::getPointerToGlobal(GlobalValue *V, void *Reference,
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bool DoesntNeedStub) {
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if (GlobalVariable *GV = dyn_cast<GlobalVariable>(V)) {
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/// FIXME: If we straightened things out, this could actually emit the
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/// global immediately instead of queuing it for codegen later!
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return TheJIT->getOrEmitGlobalVariable(GV);
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}
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// If we have already compiled the function, return a pointer to its body.
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Function *F = cast<Function>(V);
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void *ResultPtr = TheJIT->getPointerToGlobalIfAvailable(F);
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if (ResultPtr) return ResultPtr;
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if (F->hasExternalLinkage() && F->isExternal()) {
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// If this is an external function pointer, we can force the JIT to
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// 'compile' it, which really just adds it to the map.
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if (DoesntNeedStub)
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return TheJIT->getPointerToFunction(F);
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return getJITResolver(this).getFunctionStub(F);
|
|
}
|
|
|
|
// Okay, the function has not been compiled yet, if the target callback
|
|
// mechanism is capable of rewriting the instruction directly, prefer to do
|
|
// that instead of emitting a stub.
|
|
if (DoesntNeedStub)
|
|
return getJITResolver(this).AddCallbackAtLocation(F, Reference);
|
|
|
|
// Otherwise, we have to emit a lazy resolving stub.
|
|
return getJITResolver(this).getFunctionStub(F);
|
|
}
|
|
|
|
void JITEmitter::startFunction(MachineFunction &F) {
|
|
CurByte = CurBlock = MemMgr.startFunctionBody();
|
|
TheJIT->addGlobalMapping(F.getFunction(), CurBlock);
|
|
}
|
|
|
|
void JITEmitter::finishFunction(MachineFunction &F) {
|
|
MemMgr.endFunctionBody(CurByte);
|
|
NumBytes += CurByte-CurBlock;
|
|
|
|
if (!Relocations.empty()) {
|
|
NumRelos += Relocations.size();
|
|
|
|
// Resolve the relocations to concrete pointers.
|
|
for (unsigned i = 0, e = Relocations.size(); i != e; ++i) {
|
|
MachineRelocation &MR = Relocations[i];
|
|
void *ResultPtr;
|
|
if (MR.isString()) {
|
|
ResultPtr = TheJIT->getPointerToNamedFunction(MR.getString());
|
|
|
|
// If the target REALLY wants a stub for this function, emit it now.
|
|
if (!MR.doesntNeedFunctionStub())
|
|
ResultPtr = getJITResolver(this).getExternalFunctionStub(ResultPtr);
|
|
} else if (MR.isGlobalValue())
|
|
ResultPtr = getPointerToGlobal(MR.getGlobalValue(),
|
|
CurBlock+MR.getMachineCodeOffset(),
|
|
MR.doesntNeedFunctionStub());
|
|
else //ConstantPoolIndex
|
|
ResultPtr =
|
|
(void*)(intptr_t)getConstantPoolEntryAddress(MR.getConstantPoolIndex());
|
|
|
|
MR.setResultPointer(ResultPtr);
|
|
|
|
// if we are managing the GOT and the relocation wants an index,
|
|
// give it one
|
|
if (MemMgr.isManagingGOT() && !MR.isConstantPoolIndex() &&
|
|
MR.isGOTRelative()) {
|
|
unsigned idx = getJITResolver(this).getGOTIndexForAddr(ResultPtr);
|
|
MR.setGOTIndex(idx);
|
|
if (((void**)MemMgr.getGOTBase())[idx] != ResultPtr) {
|
|
DEBUG(std::cerr << "GOT was out of date for " << ResultPtr
|
|
<< " pointing at " << ((void**)MemMgr.getGOTBase())[idx] << "\n");
|
|
((void**)MemMgr.getGOTBase())[idx] = ResultPtr;
|
|
}
|
|
}
|
|
}
|
|
|
|
TheJIT->getJITInfo().relocate(CurBlock, &Relocations[0],
|
|
Relocations.size(), MemMgr.getGOTBase());
|
|
}
|
|
|
|
//Update the GOT entry for F to point to the new code.
|
|
if(MemMgr.isManagingGOT()) {
|
|
unsigned idx = getJITResolver(this).getGOTIndexForAddr((void*)CurBlock);
|
|
if (((void**)MemMgr.getGOTBase())[idx] != (void*)CurBlock) {
|
|
DEBUG(std::cerr << "GOT was out of date for " << (void*)CurBlock
|
|
<< " pointing at " << ((void**)MemMgr.getGOTBase())[idx] << "\n");
|
|
((void**)MemMgr.getGOTBase())[idx] = (void*)CurBlock;
|
|
}
|
|
}
|
|
|
|
DEBUG(std::cerr << "JIT: Finished CodeGen of [" << (void*)CurBlock
|
|
<< "] Function: " << F.getFunction()->getName()
|
|
<< ": " << CurByte-CurBlock << " bytes of text, "
|
|
<< Relocations.size() << " relocations\n");
|
|
Relocations.clear();
|
|
ConstantPoolAddresses.clear();
|
|
}
|
|
|
|
void JITEmitter::emitConstantPool(MachineConstantPool *MCP) {
|
|
const std::vector<Constant*> &Constants = MCP->getConstants();
|
|
if (Constants.empty()) return;
|
|
|
|
for (unsigned i = 0, e = Constants.size(); i != e; ++i) {
|
|
const Type *Ty = Constants[i]->getType();
|
|
unsigned Size = (unsigned)TheJIT->getTargetData().getTypeSize(Ty);
|
|
unsigned Alignment = TheJIT->getTargetData().getTypeAlignment(Ty);
|
|
|
|
void *Addr = MemMgr.allocateConstant(Size, Alignment);
|
|
TheJIT->InitializeMemory(Constants[i], Addr);
|
|
ConstantPoolAddresses.push_back(Addr);
|
|
}
|
|
}
|
|
|
|
void JITEmitter::startFunctionStub(unsigned StubSize) {
|
|
SavedCurBlock = CurBlock; SavedCurByte = CurByte;
|
|
CurByte = CurBlock = MemMgr.allocateStub(StubSize);
|
|
}
|
|
|
|
void *JITEmitter::finishFunctionStub(const Function *F) {
|
|
NumBytes += CurByte-CurBlock;
|
|
std::swap(CurBlock, SavedCurBlock);
|
|
CurByte = SavedCurByte;
|
|
return SavedCurBlock;
|
|
}
|
|
|
|
void JITEmitter::emitByte(unsigned char B) {
|
|
*CurByte++ = B; // Write the byte to memory
|
|
}
|
|
|
|
void JITEmitter::emitWord(unsigned W) {
|
|
// This won't work if the endianness of the host and target don't agree! (For
|
|
// a JIT this can't happen though. :)
|
|
*(unsigned*)CurByte = W;
|
|
CurByte += sizeof(unsigned);
|
|
}
|
|
|
|
void JITEmitter::emitWordAt(unsigned W, unsigned *Ptr) {
|
|
*Ptr = W;
|
|
}
|
|
|
|
// getConstantPoolEntryAddress - Return the address of the 'ConstantNum' entry
|
|
// in the constant pool that was last emitted with the 'emitConstantPool'
|
|
// method.
|
|
//
|
|
uint64_t JITEmitter::getConstantPoolEntryAddress(unsigned ConstantNum) {
|
|
assert(ConstantNum < ConstantPoolAddresses.size() &&
|
|
"Invalid ConstantPoolIndex!");
|
|
return (intptr_t)ConstantPoolAddresses[ConstantNum];
|
|
}
|
|
|
|
unsigned char* JITEmitter::allocateGlobal(unsigned size, unsigned alignment)
|
|
{
|
|
return MemMgr.allocateGlobal(size, alignment);
|
|
}
|
|
|
|
// getCurrentPCValue - This returns the address that the next emitted byte
|
|
// will be output to.
|
|
//
|
|
uint64_t JITEmitter::getCurrentPCValue() {
|
|
return (intptr_t)CurByte;
|
|
}
|
|
|
|
uint64_t JITEmitter::getCurrentPCOffset() {
|
|
return (intptr_t)CurByte-(intptr_t)CurBlock;
|
|
}
|
|
|
|
// getPointerToNamedFunction - This function is used as a global wrapper to
|
|
// JIT::getPointerToNamedFunction for the purpose of resolving symbols when
|
|
// bugpoint is debugging the JIT. In that scenario, we are loading an .so and
|
|
// need to resolve function(s) that are being mis-codegenerated, so we need to
|
|
// resolve their addresses at runtime, and this is the way to do it.
|
|
extern "C" {
|
|
void *getPointerToNamedFunction(const char *Name) {
|
|
Module &M = TheJIT->getModule();
|
|
if (Function *F = M.getNamedFunction(Name))
|
|
return TheJIT->getPointerToFunction(F);
|
|
return TheJIT->getPointerToNamedFunction(Name);
|
|
}
|
|
}
|