On Tue, Sep 23, 2014 at 8:48 AM, Ilya Enkovich <enkovich....@gmail.com> wrote: > 2014-09-22 22:51 GMT+04:00 Uros Bizjak <ubiz...@gmail.com>: >> On Mon, Sep 22, 2014 at 5:30 PM, Ilya Enkovich <enkovich....@gmail.com> >> wrote: >>> On 19 Sep 18:21, Uros Bizjak wrote: >>>> On Fri, Sep 19, 2014 at 2:53 PM, Ilya Enkovich <enkovich....@gmail.com> >>>> wrote: >>>> >>>> >> > This patch adds i386 target hooks for Pointer Bounds Checker. >>>> >>>> > New version with fixes and better documentation for ix86_load_bounds and >>>> > ix86_store_bounds is below. >>>> >>>> > +/* Expand pass uses this hook to load bounds for function parameter >>>> > + PTR passed in SLOT in case its bounds are not passed in a register. >>>> > + >>>> > + If SLOT is a memory, then bounds are loaded as for regular pointer >>>> > + loaded from memory. PTR may be NULL in case SLOT is a memory. >>>> > + In such case value of PTR (if required) may be loaded from SLOT. >>>> > + >>>> > + If SLOT is NULL or a register then SLOT_NO is an integer constant >>>> > + holding number of the target dependent special slot which should be >>>> > + used to obtain bounds. >>>> > + >>>> > + Return loaded bounds. */ >>>> >>>> OK, I hope I understand this target-handling of SLOT_NO. Can you >>>> please clarify when SLOT is a register? >>> >>> For functions with more than four pointers passed in registers we do not >>> have enough bound registers to pass bounds. These hooks are called then >>> with SLOT set to register used to pass pointer >>> >>>> >>>> I propose to write this function in the following (hopefully equivalent) >>>> way: >>> >>> Since addr computation is very similar for both loading and storing (the >>> only difference is usage of either arg_pointer_rtx or stack_pointer_rtx) I >>> decided additionally move it into a separate function. This should make >>> functions simplier for understanding. >> >> LGTM, just add the explanation when NULL is returned. > > There is no path in this function returning NULL (we are talking about > ix86_get_arg_address_for_bt, right?).
Oh, in fact, I was looking at ix86_function_value_bounds which doesn't have comment at all... Looking a bit more, there are some other functions without comments Uros.
