Re: [PATCH 1/2] allow target to check shrink-wrap-separate enabled or not

[Jeff Law via Gcc-patches]

On 6/20/23 03:40, Fei Gao wrote:
gcc/ChangeLog:

         * shrink-wrap.cc (try_shrink_wrapping_separate):call
           use_shrink_wrapping_separate.
         (use_shrink_wrapping_separate): wrap the condition
           check in use_shrink_wrapping_separate.
         * shrink-wrap.h (use_shrink_wrapping_separate): add to extern
I'm still missing somethign here.

Why doesn't the RISC-V target simply disable separate shrink wrapping by 
indicating no components are eligible in the relevant cases.  ie, I do 
not think we need another knob here.

To be more concrete:

/* Implement TARGET_SHRINK_WRAP_GET_SEPARATE_COMPONENTS.  */
  
static sbitmap
riscv_get_separate_components (void)
{       
  HOST_WIDE_INT offset;
  sbitmap components = sbitmap_alloc (FIRST_PSEUDO_REGISTER);
  bitmap_clear (components);
          
  if (riscv_use_save_libcall (&cfun->machine->frame)
      || cfun->machine->interrupt_handler_p
      || !cfun->machine->frame.gp_sp_offset.is_constant ())
    return components;
Don't we get the behavior we want if we change this code to return an 
zero'd sbitmap?

jeff