JIT.cpp revision 954da37bb492b519f5c31dc360f2a142567e08b4
14d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner//===-- JIT.cpp - LLVM Just in Time Compiler ------------------------------===// 2b576c94c15af9a440f69d9d03c2afead7971118cJohn Criswell// 3b576c94c15af9a440f69d9d03c2afead7971118cJohn Criswell// The LLVM Compiler Infrastructure 4b576c94c15af9a440f69d9d03c2afead7971118cJohn Criswell// 5b576c94c15af9a440f69d9d03c2afead7971118cJohn Criswell// This file was developed by the LLVM research group and is distributed under 6b576c94c15af9a440f69d9d03c2afead7971118cJohn Criswell// the University of Illinois Open Source License. See LICENSE.TXT for details. 7b576c94c15af9a440f69d9d03c2afead7971118cJohn Criswell// 8b576c94c15af9a440f69d9d03c2afead7971118cJohn Criswell//===----------------------------------------------------------------------===// 9bd199fb1148b9e16c4e6f3d0ee386c2505a55b71Chris Lattner// 104d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner// This tool implements a just-in-time compiler for LLVM, allowing direct 114d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner// execution of LLVM bytecode in an efficient manner. 12bd199fb1148b9e16c4e6f3d0ee386c2505a55b71Chris Lattner// 13bd199fb1148b9e16c4e6f3d0ee386c2505a55b71Chris Lattner//===----------------------------------------------------------------------===// 14bd199fb1148b9e16c4e6f3d0ee386c2505a55b71Chris Lattner 154d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner#include "JIT.h" 16c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner#include "llvm/DerivedTypes.h" 174d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner#include "llvm/Function.h" 18c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner#include "llvm/GlobalVariable.h" 190f4f7d9eb72dec2a72ec596fb3d611a241893bb7Misha Brukman#include "llvm/ModuleProvider.h" 204d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner#include "llvm/CodeGen/MachineCodeEmitter.h" 214d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner#include "llvm/CodeGen/MachineFunction.h" 229722294d30fff2a432d8e171eb904f33956353e2Brian Gaeke#include "llvm/ExecutionEngine/GenericValue.h" 23bd199fb1148b9e16c4e6f3d0ee386c2505a55b71Chris Lattner#include "llvm/Target/TargetMachine.h" 244d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner#include "llvm/Target/TargetJITInfo.h" 25c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner#include "Support/DynamicLinker.h" 26954da37bb492b519f5c31dc360f2a142567e08b4Reid Spencer#include <iostream> 27954da37bb492b519f5c31dc360f2a142567e08b4Reid Spencer 28c19aadee66b744311afe6e420847e80822a765f2Chris Lattnerusing namespace llvm; 29abb027cf412944db4d27579ba3ae00717d23c25eMisha Brukman 304d326fa9bea5b80147edf14d1521fc41ce315275Chris LattnerJIT::JIT(ModuleProvider *MP, TargetMachine &tm, TargetJITInfo &tji) 311e60a9165dc4d6ce5650dacc026f2942696af920Chris Lattner : ExecutionEngine(MP), TM(tm), TJI(tji), PM(MP) { 32bd199fb1148b9e16c4e6f3d0ee386c2505a55b71Chris Lattner setTargetData(TM.getTargetData()); 33abb027cf412944db4d27579ba3ae00717d23c25eMisha Brukman 34abb027cf412944db4d27579ba3ae00717d23c25eMisha Brukman // Initialize MCE 35906f5fa5c8bb790201c79a33ea6d906f9f57f827Misha Brukman MCE = createEmitter(*this); 361e60a9165dc4d6ce5650dacc026f2942696af920Chris Lattner 3750872d5385463cf1d2e23a758516e7f818e1af24Brian Gaeke // Add target data 3850872d5385463cf1d2e23a758516e7f818e1af24Brian Gaeke PM.add (new TargetData (TM.getTargetData ())); 3950872d5385463cf1d2e23a758516e7f818e1af24Brian Gaeke 404d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner // Compile LLVM Code down to machine code in the intermediate representation 414d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner TJI.addPassesToJITCompile(PM); 424d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner 434d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner // Turn the machine code intermediate representation into bytes in memory that 444d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner // may be executed. 454d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner if (TM.addPassesToEmitMachineCode(PM, *MCE)) { 464d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner std::cerr << "lli: target '" << TM.getName() 474d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner << "' doesn't support machine code emission!\n"; 484d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner abort(); 494d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner } 50bd199fb1148b9e16c4e6f3d0ee386c2505a55b71Chris Lattner} 51bd199fb1148b9e16c4e6f3d0ee386c2505a55b71Chris Lattner 524d326fa9bea5b80147edf14d1521fc41ce315275Chris LattnerJIT::~JIT() { 534d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner delete MCE; 544d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner delete &TM; 554d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner} 564d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner 5770975eef572b9e132bbaade16ba9edb76f15f287Brian Gaeke/// run - Start execution with the specified function and arguments. 5805a1a306bcfba2b533dc1210d24924e5f3e9ed0eChris Lattner/// 59ff0f1bb32a439cf82cb09ee29544c894a2bfe877Chris LattnerGenericValue JIT::runFunction(Function *F, 60ff0f1bb32a439cf82cb09ee29544c894a2bfe877Chris Lattner const std::vector<GenericValue> &ArgValues) { 6170975eef572b9e132bbaade16ba9edb76f15f287Brian Gaeke assert (F && "Function *F was null at entry to run()"); 62ff0f1bb32a439cf82cb09ee29544c894a2bfe877Chris Lattner GenericValue rv; 63bd199fb1148b9e16c4e6f3d0ee386c2505a55b71Chris Lattner 64ff0f1bb32a439cf82cb09ee29544c894a2bfe877Chris Lattner if (ArgValues.size() == 3) { 65ff0f1bb32a439cf82cb09ee29544c894a2bfe877Chris Lattner int (*PF)(int, char **, const char **) = 66ff0f1bb32a439cf82cb09ee29544c894a2bfe877Chris Lattner (int(*)(int, char **, const char **))getPointerToFunction(F); 67ff0f1bb32a439cf82cb09ee29544c894a2bfe877Chris Lattner assert(PF && "Pointer to fn's code was null after getPointerToFunction"); 68ff0f1bb32a439cf82cb09ee29544c894a2bfe877Chris Lattner 69ff0f1bb32a439cf82cb09ee29544c894a2bfe877Chris Lattner // Call the function. 70ff0f1bb32a439cf82cb09ee29544c894a2bfe877Chris Lattner int ExitCode = PF(ArgValues[0].IntVal, (char **) GVTOP (ArgValues[1]), 71ff0f1bb32a439cf82cb09ee29544c894a2bfe877Chris Lattner (const char **) GVTOP (ArgValues[2])); 72ff0f1bb32a439cf82cb09ee29544c894a2bfe877Chris Lattner 73ff0f1bb32a439cf82cb09ee29544c894a2bfe877Chris Lattner rv.IntVal = ExitCode; 74ff0f1bb32a439cf82cb09ee29544c894a2bfe877Chris Lattner } else { 75ff0f1bb32a439cf82cb09ee29544c894a2bfe877Chris Lattner // FIXME: This code should handle a couple of common cases efficiently, but 76ff0f1bb32a439cf82cb09ee29544c894a2bfe877Chris Lattner // it should also implement the general case by code-gening a new anonymous 77ff0f1bb32a439cf82cb09ee29544c894a2bfe877Chris Lattner // nullary function to call. 78ff0f1bb32a439cf82cb09ee29544c894a2bfe877Chris Lattner assert(ArgValues.size() == 1); 79ff0f1bb32a439cf82cb09ee29544c894a2bfe877Chris Lattner void (*PF)(int) = (void(*)(int))getPointerToFunction(F); 80ff0f1bb32a439cf82cb09ee29544c894a2bfe877Chris Lattner assert(PF && "Pointer to fn's code was null after getPointerToFunction"); 81ff0f1bb32a439cf82cb09ee29544c894a2bfe877Chris Lattner PF(ArgValues[0].IntVal); 82ff0f1bb32a439cf82cb09ee29544c894a2bfe877Chris Lattner } 8370975eef572b9e132bbaade16ba9edb76f15f287Brian Gaeke 8470975eef572b9e132bbaade16ba9edb76f15f287Brian Gaeke return rv; 85bd199fb1148b9e16c4e6f3d0ee386c2505a55b71Chris Lattner} 864d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner 874d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner/// runJITOnFunction - Run the FunctionPassManager full of 884d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner/// just-in-time compilation passes on F, hopefully filling in 894d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner/// GlobalAddress[F] with the address of F's machine code. 904d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner/// 914d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattnervoid JIT::runJITOnFunction(Function *F) { 924d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner static bool isAlreadyCodeGenerating = false; 934d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner assert(!isAlreadyCodeGenerating && "Error: Recursive compilation detected!"); 944d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner 954d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner // JIT the function 964d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner isAlreadyCodeGenerating = true; 974d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner PM.run(*F); 984d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner isAlreadyCodeGenerating = false; 99c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner 100c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner // If the function referred to a global variable that had not yet been 101c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner // emitted, it allocates memory for the global, but doesn't emit it yet. Emit 102c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner // all of these globals now. 103c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner while (!PendingGlobals.empty()) { 104c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner const GlobalVariable *GV = PendingGlobals.back(); 105c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner PendingGlobals.pop_back(); 106c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner EmitGlobalVariable(GV); 107c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner } 1084d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner} 1094d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner 1104d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner/// getPointerToFunction - This method is used to get the address of the 1114d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner/// specified function, compiling it if neccesary. 1124d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner/// 1134d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattnervoid *JIT::getPointerToFunction(Function *F) { 114c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner if (void *Addr = getPointerToGlobalIfAvailable(F)) 115c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner return Addr; // Check if function already code gen'd 1164d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner 1174d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner // Make sure we read in the function if it exists in this Module 118da79bd2322b63c2568e760ce5d3842bade9b3ecfChris Lattner try { 119da79bd2322b63c2568e760ce5d3842bade9b3ecfChris Lattner MP->materializeFunction(F); 120da79bd2322b63c2568e760ce5d3842bade9b3ecfChris Lattner } catch (...) { 121da79bd2322b63c2568e760ce5d3842bade9b3ecfChris Lattner std::cerr << "Error parsing bytecode file!\n"; 122da79bd2322b63c2568e760ce5d3842bade9b3ecfChris Lattner abort(); 123da79bd2322b63c2568e760ce5d3842bade9b3ecfChris Lattner } 1244d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner 125c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner if (F->isExternal()) { 126c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner void *Addr = getPointerToNamedFunction(F->getName()); 127c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner addGlobalMapping(F, Addr); 128c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner return Addr; 129c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner } 1304d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner 1314d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner runJITOnFunction(F); 132c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner 133c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner void *Addr = getPointerToGlobalIfAvailable(F); 1344d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner assert(Addr && "Code generation didn't add function to GlobalAddress table!"); 1354d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner return Addr; 1364d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner} 1374d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner 1384d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner// getPointerToFunctionOrStub - If the specified function has been 1394d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner// code-gen'd, return a pointer to the function. If not, compile it, or use 1404d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner// a stub to implement lazy compilation if available. 1414d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner// 1424d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattnervoid *JIT::getPointerToFunctionOrStub(Function *F) { 1434d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner // If we have already code generated the function, just return the address. 144c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner if (void *Addr = getPointerToGlobalIfAvailable(F)) 145c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner return Addr; 1464d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner 1474d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner // If the target supports "stubs" for functions, get a stub now. 1484d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner if (void *Ptr = TJI.getJITStubForFunction(F, *MCE)) 1494d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner return Ptr; 1504d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner 1514d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner // Otherwise, if the target doesn't support it, just codegen the function. 1524d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner return getPointerToFunction(F); 1534d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner} 1544d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner 155c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner/// getOrEmitGlobalVariable - Return the address of the specified global 156c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner/// variable, possibly emitting it to memory if needed. This is used by the 157c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner/// Emitter. 158c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattnervoid *JIT::getOrEmitGlobalVariable(const GlobalVariable *GV) { 159c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner void *Ptr = getPointerToGlobalIfAvailable(GV); 160c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner if (Ptr) return Ptr; 161c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner 162c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner // If the global is external, just remember the address. 163c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner if (GV->isExternal()) { 164c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner Ptr = GetAddressOfSymbol(GV->getName().c_str()); 165c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner if (Ptr == 0) { 166c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner std::cerr << "Could not resolve external global address: " 167c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner << GV->getName() << "\n"; 168c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner abort(); 169c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner } 170c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner } else { 171c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner // If the global hasn't been emitted to memory yet, allocate space. We will 172c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner // actually initialize the global after current function has finished 173c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner // compilation. 174c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner Ptr =new char[getTargetData().getTypeSize(GV->getType()->getElementType())]; 175c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner PendingGlobals.push_back(GV); 176c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner } 177c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner addGlobalMapping(GV, Ptr); 178c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner return Ptr; 179c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner} 180c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner 181c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner 1824d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner/// recompileAndRelinkFunction - This method is used to force a function 1834d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner/// which has already been compiled, to be compiled again, possibly 1844d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner/// after it has been modified. Then the entry to the old copy is overwritten 1854d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner/// with a branch to the new copy. If there was no old copy, this acts 1864d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner/// just like JIT::getPointerToFunction(). 1874d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner/// 1884d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattnervoid *JIT::recompileAndRelinkFunction(Function *F) { 189c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner void *OldAddr = getPointerToGlobalIfAvailable(F); 1904d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner 191c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner // If it's not already compiled there is no reason to patch it up. 192c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner if (OldAddr == 0) { return getPointerToFunction(F); } 1934d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner 194c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner // Delete the old function mapping. 195c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner addGlobalMapping(F, 0); 196c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner 197c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner // Recodegen the function 1984d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner runJITOnFunction(F); 199c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner 200c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner // Update state, forward the old function to the new function. 201c07ed1387503d25c0b93fcf617f69329d73fc589Chris Lattner void *Addr = getPointerToGlobalIfAvailable(F); 2024d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner assert(Addr && "Code generation didn't add function to GlobalAddress table!"); 2034d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner TJI.replaceMachineCodeForFunction(OldAddr, Addr); 2044d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner return Addr; 2054d326fa9bea5b80147edf14d1521fc41ce315275Chris Lattner} 206