LLVM emscripting

configure.txt

--enable-optimized
--disable-polly
--disable-clang-arcmt
--disable-clang-static-analyzer
--disable-clang-rewriter
--disable-assertions
--disable-debug-symbols
--disable-jit
--disable-docs
--disable-threads
--disable-pthreads
--disable-zlib
--disable-pic
--disable-timestamps
--disable-stacktraces
--enable-target=x86

test.cc

#ifndef CHAR_BIT
# define CHAR_BIT __CHAR_BIT__
#endif

#include <iostream>
#include <string>
#include <vector>

#include <llvm/ExecutionEngine/ExecutionEngine.h>
#include <llvm/ExecutionEngine/GenericValue.h>
#include <llvm/ExecutionEngine/Interpreter.h>
#include <llvm/IR/BasicBlock.h>
#include <llvm/IR/Constants.h>
#include <llvm/IR/Function.h>
#include <llvm/IR/IRBuilder.h>
#include <llvm/IR/LLVMContext.h>
#include <llvm/IR/Module.h>
#include <llvm/IR/Type.h>
#include <llvm/Support/TargetSelect.h>

int main( void ) {
  llvm::InitializeNativeTarget();
  llvm::LLVMContext context;
  llvm::Module module("foo", context);

  llvm::Type * dbl = llvm::Type::getDoubleTy(context);
  llvm::FunctionType * type = llvm::FunctionType::get(dbl, std::vector<llvm::Type*>(), false);
  llvm::Function * fn = llvm::Function::Create(type, llvm::Function::ExternalLinkage, "fn", &module);
  llvm::BasicBlock * bb = llvm::BasicBlock::Create(context, "entry", fn);

  llvm::IRBuilder<> builder(bb);
  builder.CreateRet(llvm::ConstantFP::get(dbl, 42.0));

  llvm::ExecutionEngine * engine = llvm::EngineBuilder(&module).setEngineKind(llvm::EngineKind::Interpreter).create();
  std::cout << engine->runFunction(fn, std::vector<llvm::GenericValue>()).DoubleVal << std::endl;
}