X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=examples%2FHowToUseJIT%2FHowToUseJIT.cpp;h=5fa4237179f7605fd0694f0b02394ec3ef17ea48;hb=73b43b9b549a75fb0015c825df68abd95705a67c;hp=16f4657c62bd1a9fd5f46206a4f319866eb28135;hpb=54706d680107a3809985bf1308b198c7b1d0f7f5;p=oota-llvm.git diff --git a/examples/HowToUseJIT/HowToUseJIT.cpp b/examples/HowToUseJIT/HowToUseJIT.cpp index 16f4657c62b..5fa4237179f 100644 --- a/examples/HowToUseJIT/HowToUseJIT.cpp +++ b/examples/HowToUseJIT/HowToUseJIT.cpp @@ -1,151 +1,112 @@ -//===--- HowToUseJIT.cpp - An example use of the JIT ----------------------===// -// +//===-- examples/HowToUseJIT/HowToUseJIT.cpp - An example use of the JIT --===// +// // The LLVM Compiler Infrastructure // -// This file was developed by Valery A. Khamenya and is distributed under the -// University of Illinois Open Source License. See LICENSE.TXT for details. -// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// //===----------------------------------------------------------------------===// // // This small program provides an example of how to quickly build a small -// module with two functions and execute it with the JIT. -// -//===------------------------------------------------------------------------=== - -// Goal: +// module with two functions and execute it with the JIT. +// +// Goal: // The goal of this snippet is to create in the memory // the LLVM module consisting of two functions as follow: // // int add1(int x) { // return x+1; // } -// +// // int foo() { // return add1(10); // } -// -// then compile the module via JIT, then execute the `foo' +// +// then compile the module via JIT, then execute the `foo' // function and return result to a driver, i.e. to a "host program". -// +// // Some remarks and questions: -// +// // - could we invoke some code using noname functions too? -// e.g. evaluate "foo()+foo()" without fears to introduce +// e.g. evaluate "foo()+foo()" without fears to introduce // conflict of temporary function name with some real // existing function name? -// +// +//===----------------------------------------------------------------------===// +#include "llvm/Module.h" +#include "llvm/Constants.h" +#include "llvm/DerivedTypes.h" +#include "llvm/Instructions.h" +#include "llvm/ModuleProvider.h" +#include "llvm/ExecutionEngine/JIT.h" +#include "llvm/ExecutionEngine/Interpreter.h" +#include "llvm/ExecutionEngine/GenericValue.h" #include +using namespace llvm; -#include -#include -#include -#include -#include +int main() { + // Create some module to put our function into it. + Module *M = new Module("test"); -#include "llvm/ExecutionEngine/ExecutionEngine.h" -#include "llvm/ExecutionEngine/GenericValue.h" + // Create the add1 function entry and insert this entry into module M. The + // function will have a return type of "int" and take an argument of "int". + // The '0' terminates the list of argument types. + Function *Add1F = + cast(M->getOrInsertFunction("add1", Type::Int32Ty, Type::Int32Ty, + (Type *)0)); + // Add a basic block to the function. As before, it automatically inserts + // because of the last argument. + BasicBlock *BB = BasicBlock::Create("EntryBlock", Add1F); -using namespace llvm; + // Get pointers to the constant `1'. + Value *One = ConstantInt::get(Type::Int32Ty, 1); -int main() { + // Get pointers to the integer argument of the add1 function... + assert(Add1F->arg_begin() != Add1F->arg_end()); // Make sure there's an arg + Argument *ArgX = Add1F->arg_begin(); // Get the arg + ArgX->setName("AnArg"); // Give it a nice symbolic name for fun. - // Create some module to put our function into it. - Module *M = new Module("test"); + // Create the add instruction, inserting it into the end of BB. + Instruction *Add = BinaryOperator::CreateAdd(One, ArgX, "addresult", BB); + + // Create the return instruction and add it to the basic block + ReturnInst::Create(Add, BB); + + // Now, function add1 is ready. - // We are about to create the add1 function: - Function *Add1F; - - { - // first create type for the single argument of add1 function: - // the type is 'int ()' - std::vector ArgT(1); - ArgT[0] = Type::IntTy; - - // now create full type of the add1 function: - FunctionType *Add1T = FunctionType::get(Type::IntTy, // type of result - ArgT, - /*not vararg*/false); - - // Now create the add1 function entry and - // insert this entry into module M - // (By passing a module as the last parameter to the Function constructor, - // it automatically gets appended to the Module.) - Add1F = new Function(Add1T, - Function::ExternalLinkage, // maybe too much - "add1", M); - - // Add a basic block to the function... (again, it automatically inserts - // because of the last argument.) - BasicBlock *BB = new BasicBlock("EntryBlock of add1 function", Add1F); - - // Get pointers to the constant `1'... - Value *One = ConstantSInt::get(Type::IntTy, 1); - - // Get pointers to the integer argument of the add1 function... - assert(Add1F->abegin() != Add1F->aend()); // Make sure there's an arg - Argument &ArgX = Add1F->afront(); // Get the arg - - // Create the add instruction... does not insert... - Instruction *Add = BinaryOperator::create(Instruction::Add, One, &ArgX, - "addresult"); - - // explicitly insert it into the basic block... - BB->getInstList().push_back(Add); - - // Create the return instruction and add it to the basic block - BB->getInstList().push_back(new ReturnInst(Add)); - - // function add1 is ready - } - - - // now we going to create function `foo': - Function *FooF; - - { - // Create the foo function type: - FunctionType *FooT = - FunctionType::get(Type::IntTy, // result has type: 'int ()' - std::vector(), // no arguments - /*not vararg*/false); - - // create the entry for function `foo' and insert - // this entry into module M: - FooF = - new Function(FooT, - Function::ExternalLinkage, // too wide? - "foo", M); - - // Add a basic block to the FooF function... - BasicBlock *BB = new BasicBlock("EntryBlock of add1 function", FooF); - - // Get pointers to the constant `10'... - Value *Ten = ConstantSInt::get(Type::IntTy, 10); - - // Put the argument Ten on stack and make call: - // ... - std::vector Params; - Params.push_back(Ten); - CallInst * Add1CallRes = new CallInst(Add1F, Params, "add1", BB); - - // Create the return instruction and add it to the basic block - BB->getInstList().push_back(new ReturnInst(Add1CallRes)); - - } - - // Now we going to create JIT ?? + // Now we going to create function `foo', which returns an int and takes no + // arguments. + Function *FooF = + cast(M->getOrInsertFunction("foo", Type::Int32Ty, (Type *)0)); + + // Add a basic block to the FooF function. + BB = BasicBlock::Create("EntryBlock", FooF); + + // Get pointers to the constant `10'. + Value *Ten = ConstantInt::get(Type::Int32Ty, 10); + + // Pass Ten to the call call: + CallInst *Add1CallRes = CallInst::Create(Add1F, Ten, "add1", BB); + Add1CallRes->setTailCall(true); + + // Create the return instruction and add it to the basic block. + ReturnInst::Create(Add1CallRes, BB); + + // Now we create the JIT. ExistingModuleProvider* MP = new ExistingModuleProvider(M); - ExecutionEngine* EE = ExecutionEngine::create( MP, true ); + ExecutionEngine* EE = ExecutionEngine::create(MP, false); + + std::cout << "We just constructed this LLVM module:\n\n" << *M; + std::cout << "\n\nRunning foo: " << std::flush; // Call the `foo' function with no arguments: std::vector noargs; GenericValue gv = EE->runFunction(FooF, noargs); - // import result of execution: - std::cout << "Result: " << gv.IntVal << std:: endl; - + // Import result of execution: + std::cout << "Result: " << gv.IntVal.toStringUnsigned(10) << "\n"; return 0; }