llvm dev - Apr 2006 - [LLVMdev] standalone llvm

Is it possible to get llvm to generate native machine code
without using gcc and friends ? Do I use lli ?

I'd like to directly create executable code that i can
stick in memory somewhere and jump into (call).

(I'm looking to use llvm in a BSD licensed project).

Simon.

-- 
Simon Burton, B.Sc.
Licensed PO Box 8066
ANU Canberra 2601
Australia
Ph. 61 02 6249 6940
http://arrowtheory.com

On Apr 12, 2006, at 10:23 PM, Simon Burton wrote:
>
> Is it possible to get llvm to generate native machine code
> without using gcc and friends ? Do I use lli ?
llc.  llc --help lists all the options.  it compiles llvm bytecode  
files.
>
> I'd like to directly create executable code that i can
> stick in memory somewhere and jump into (call).
>
> (I'm looking to use llvm in a BSD licensed project).
>
> Simon.
>
> -- 
> Simon Burton, B.Sc.
> Licensed PO Box 8066
> ANU Canberra 2601
> Australia
> Ph. 61 02 6249 6940
> http://arrowtheory.com
>
> _______________________________________________
> LLVM Developers mailing list
> LLVMdev at cs.uiuc.edu         http://llvm.cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev

On Thu, 13 Apr 2006, Simon Burton wrote:
>
> Is it possible to get llvm to generate native machine code
> without using gcc and friends ? Do I use lli ?
LLVM only needs llvm-gcc to translate from C/C++ to LLVM IR.  If you 
already have code in LLVM IR form (e.g. because you're generating it on 
the fly or you have your own front-end) you don't need llvm-gcc.
> I'd like to directly create executable code that i can
> stick in memory somewhere and jump into (call).
Take a look at the llvm/examples directory.  There are several small 
programs that create LLVM IR on the fly and JIT compile it.

-Chris

-- 
http://nondot.org/sabre/
http://llvm.org/

On Wed, 12 Apr 2006 22:48:16 -0500
Patrick Meredith <pmeredit at uiuc.edu> wrote:
> 
> On Apr 12, 2006, at 10:23 PM, Simon Burton wrote:
> 
> >
> > Is it possible to get llvm to generate native machine code
> > without using gcc and friends ? Do I use lli ?
> 
> llc.  llc --help lists all the options.  it compiles llvm bytecode  
> files.
It seems this does not yet work on X86. Are there some restrictions I could
adhere to in order to get something to work ?

Simon.

$ llc -filetype=dynlib -f -o=helloworld.so helloworld.bc
llc: target 'X86' does not support generation of this file type!

$ llc -filetype=obj -f -mcpu=i386 -march=x86 -o=helloworld.o helloworld.bc
llc: ELFWriter.cpp:81: virtual void llvm::ELFCodeEmitter::addRelocation(const
llvm::MachineRelocation&): Assertion `0 && "relo not handled
yet!"' failed.
llc((anonymous namespace)::PrintStackTrace()+0x1a)[0x8ac5736]
llc((anonymous namespace)::SignalHandler(int)+0xed)[0x8ac59cb]
[0xffffe420]
/lib/tls/libc.so.6(abort+0x1d2)[0xb7dc7fa2]
/lib/tls/libc.so.6(__assert_fail+0x10f)[0xb7dc02df]
llc(llvm::ELFCodeEmitter::getConstantPoolEntryAddress(unsigned
int)+0x0)[0x88ef650]
llc((anonymous namespace)::Emitter::emitGlobalAddressForPtr(llvm::GlobalValue*,
int)+0x77)[0x866ac5d]
llc((anonymous namespace)::Emitter::emitInstruction(llvm::MachineInstr
const&)+0xc0b)[0x866c1b1]
llc((anonymous namespace)::Emitter::emitBasicBlock(llvm::MachineBasicBlock
const&)+0xac)[0x866a9f8]
llc((anonymous
namespace)::Emitter::runOnMachineFunction(llvm::MachineFunction&)+0x115)[0x866a859]
llc(llvm::MachineFunctionPass::runOnFunction(llvm::Function&)+0x29)[0x85f3421]
llc(llvm::FunctionPassManagerT::runPass(llvm::FunctionPass*,
llvm::Function*)+0x1f)[0x89e39b5]
llc(llvm::PassManagerT<llvm::FTraits>::runPasses(llvm::Function*,
std::map<llvm::Pass*, std::vector<llvm::Pass*,
std::allocator<llvm::Pass*> >, std::less<llvm::Pass*>,
std::allocator<std::pair<llvm::Pass* const, std::vector<llvm::Pass*,
std::allocator<llvm::Pass*> > > > >&)+0x13f)[0x89e52b7]
llc(llvm::PassManagerT<llvm::FTraits>::runOnUnit(llvm::Function*)+0x17f)[0x89e4d11]
llc(llvm::FunctionPassManagerT::runOnFunction(llvm::Function&)+0x25)[0x89e5583]
llc(llvm::FunctionPass::runOnModule(llvm::Module&)+0xa7)[0x8989c63]
llc(llvm::ModulePassManager::runPass(llvm::ModulePass*,
llvm::Module*)+0x1f)[0x89e3b95]
llc(llvm::PassManagerT<llvm::MTraits>::runPasses(llvm::Module*,
std::map<llvm::Pass*, std::vector<llvm::Pass*,
std::allocator<llvm::Pass*> >, std::less<llvm::Pass*>,
std::allocator<std::pair<llvm::Pass* const, std::vector<llvm::Pass*,
std::allocator<llvm::Pass*> > > > >&)+0x13f)[0x89e5e1b]
llc(llvm::PassManagerT<llvm::MTraits>::runOnUnit(llvm::Module*)+0x17f)[0x89e5875]
llc(llvm::ModulePassManager::runOnModule(llvm::Module&)+0x25)[0x8988cc9]
llc(llvm::PassManager::run(llvm::Module&)+0x23)[0x898906d]
llc(main+0xd8c)[0x84f50b0]
/lib/tls/libc.so.6(__libc_start_main+0xf4)[0xb7db3974]
llc[0x84f4281]
Aborted


-- 
Simon Burton, B.Sc.
Licensed PO Box 8066
ANU Canberra 2601
Australia
Ph. 61 02 6249 6940
http://arrowtheory.com

On Wed, 12 Apr 2006 23:02:12 -0500 (CDT)
Chris Lattner <sabre at nondot.org> wrote:
> 
> > I'd like to directly create executable code that i can
> > stick in memory somewhere and jump into (call).
> 
> Take a look at the llvm/examples directory.  There are several small 
> programs that create LLVM IR on the fly and JIT compile it.
I'm trying to take assembly and create machine code I can execute.
How close am I ?

Simon.


int main() {
  Module *M = NULL;

  char *AsmString = "; ModuleID = 'test'\n\
\n\
implementation   ; Functions:\n\
\n\
int %add1(int %AnArg) {\n\
EntryBlock:\n\
        %addresult = add int 1, %AnArg          ; <int> [#uses=1]\n\
        ret int %addresult\n\
}\n\
";

  M = ParseAssemblyString(AsmString, NULL);

  ExistingModuleProvider* MP = new ExistingModuleProvider(M);
  ExecutionEngine* EE = ExecutionEngine::create(MP, false);

  std::cout << "We just constructed this LLVM module:\n\n"
<< *M;

  Function *F = M->getNamedFunction("add1");

  assert(F!=NULL);

  int (*add1)(int);

  add1 = (int (*)(int))EE->getPointerToFunction(F);

  std::cout << "Got:" << add1(55) << "\n";
// <----------- Bombs here <---------------

  return 0;
}



-- 
Simon Burton, B.Sc.
Licensed PO Box 8066
ANU Canberra 2601
Australia
Ph. 61 02 6249 6940
http://arrowtheory.com