------- Comment #22 from spark at gcc dot gnu dot org 2007-07-02 17:33 ------- (In reply to comment #21)
I don't think this patch is quite enough. IIUC, it is still possible (although very unlikely) for stack space to be required without any MEM_LOAD or MEM_STORE present, and without any direct reference to sp. Even if such a case is not possible, we still want to avoid sp looking as if dead for any point at function that it shouldn't be - as I pointed out earlier, after epilogue generation, because of the sp restoration, sp looks as if it's dead. This can cause a problem, e.g. if we implement any hard register renaming pass after register alloc/reload - because from df's point of view, %sp will look available between the last MEM_LOAD/MEM_STORE w/ hard fp reference, and the sp restoration code in the epilogue. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32475
