On Wed, Jul 22, 2015 at 6:55 AM, Segher Boessenkool <seg...@kernel.crashing.org> wrote: > On Wed, Jul 22, 2015 at 05:10:04AM -0700, H.J. Lu wrote: >> I got a feedback, suggesting __builtin_stack_top, instead of >> __builtin_ia32_stack_top. But I don't know if >> >> + /* After the prologue, stack top is at -WORD(AP) in the current >> + frame. */ >> + emit_insn (gen_rtx_SET (target, >> + plus_constant (Pmode, arg_pointer_rtx, >> + -UNITS_PER_WORD))); >> >> is true for all backends. If it works on all backends, I can move >> it to builtins.c. > > It doesn't afaik. But can't you define INITIAL_FRAME_ADDRESS_RTX? > > > Segher
Does INITIAL_FRAME_ADDRESS_RTX point to stack top? It certainly can't be defined for x86. I will write a midld-end patch and leave to each backend to enable it. -- H.J.
