Since STATIC_CHAIN_REGNUM is typically caller-saved, does that mean it needs to be set 1 in CALL_USED_REGISTERS ? On Thu, Apr 4, 2019 at 9:26 AM Jeff Law <law@xxxxxxxxxx> wrote: > > On 4/3/19 7:29 PM, William Tambe wrote: > > Does the prologue and epilogue need to save and restore STATIC_CHAIN_REGNUM ? > > or does GCC automatically takes care of it ? > > If a callee-saved register is used, then the prologue will need to > save/restore it. That should apply to STATIC_CHAIN_REGNUM, PIC_REGNUM > and others. > > However, typically STATIC_CHAIN_REGNUM is caller-saved -- after all it's > effectively a hidden parameter. > > Jeff
