evalString.d

string evalString(Expression e) in {
        // FIXME: newtype
        // assert(cast(SliceType) peelAlias(e.type).type, "this only CTFE strings.");
    } body {
        // Create a global variable that recieve the string.
		auto stringType = codeGen.visit(e.type);
		auto receiver = LLVMAddGlobal(codeGen.dmodule, stringType, "__ctString");
		scope(exit) LLVMDeleteGlobal(receiver);


		LLVMValueRef[2] constInit = [ LLVMConstInt( LLVMInt64TypeInContext( codeGen.llvmCtx), 0, false),
			LLVMConstNull( LLVMPointerType (LLVMInt8TypeInContext(codeGen.llvmCtx),0)) ];
		LLVMDumpValue(LLVMGetUndef(stringType));
		LLVMDumpValue(LLVMConstStruct( constInit.ptr, 2, false ));
		LLVMDumpValue(receiver);
		LLVMSetInitializer(receiver, LLVMConstStructInContext( codeGen.llvmCtx, constInit.ptr, 2, false ));
		LLVMDumpValue(receiver);

		LLVMTypeRef[1] paramTypes = [LLVMPointerType(LLVMVoidType(),0)];
		auto funType = LLVMFunctionType(LLVMVoidTypeInContext(codeGen.llvmCtx), paramTypes.ptr, 1, false);
        
        auto fun = LLVMAddFunction(codeGen.dmodule, "__ctfe", funType);
        scope(exit) LLVMDeleteFunction(fun);
        
        auto backupCurrentBB = LLVMGetInsertBlock(codeGen.builder);
        scope(exit) {
            if(backupCurrentBB) {
                LLVMPositionBuilderAtEnd(codeGen.builder, backupCurrentBB);
            } else {
                LLVMClearInsertionPosition(codeGen.builder);
            }
        }
        
        auto bodyBB = LLVMAppendBasicBlockInContext(codeGen.llvmCtx, fun, "");
        LLVMPositionBuilderAtEnd(codeGen.builder, bodyBB);
        
        // Generate function's body.
        import d.llvm.expression;
        auto eg = ExpressionGen(codeGen);


		LLVMBuildStore(codeGen.builder, 
			LLVMBuildPointerCast(codeGen.builder, eg.visit(e), LLVMPointerType(LLVMVoidType(),0), ""),
			LLVMGetFirstParam(fun));
		LLVMBuildRetVoid(codeGen.builder);
        
        codeGen.checkModule(codeGen.dmodule);
		import std.stdio;

		auto jitModule = LLVMCloneModule( codeGen.dmodule );
		//scope(exit) LLVMDisposeModule(jitModule);
		//scope(failure) LLVMDumpModule(jitModule);
		auto executionEngine = createExecutionEngine(jitModule);
		//scope(exit) LLVMDisposeExecutionEngine(executionEngine);

		auto jitFun = LLVMGetNamedFunction(jitModule, "__ctfe");
		LLVMDumpValue(jitFun);

		string foo;
        auto ret = LLVMRunFunction(executionEngine, jitFun, 1, [LLVMCreateGenericValueOfPointer(cast(void*)&foo)].ptr);
		writeln("\"",foo, "\"");
		return foo.idup; //return s.idup;
    }