Abstract: Optimization directed inlining is a good direction for inlining, but it does not consider the factor of the execution frequency and size of the function. Although a traditional inlining model considers the factor of execution frequency and size of the function, it does not consider the optimization after inlining. In this paper, a new inline model, loop fusion conscious inline model, is proposed to avoid these drawbacks of the inline model of the past. It considers both execution frequency and size and optimization. The inlining mothod which only considers loop fusion is implemented and is added into the ORC's original inline model. Then the new inline model is built and the model is tuned for high performance. In the experiment, some fact is found that temperature (execution frequency) isn't effective in some cases, and the reason is analyzed. Experiment result shows that the new model can greatly improve the performance of the compiler, and some SPEC CPU 2000 benchmark's peak performance can increase as high as 6%, and 1% on average.