Hi!
On Mon, Mar 15, 2021 at 11:11:32AM +0800, HAO CHEN GUI via Gcc-patches wrote:
> This patch adds const_anchor for rs6000. The const_anchor is used
> in cse pass.
1) This isn't suitable for stage 4.
2) Please add a test case, which shows what it does, that it is useful.
3) Does this work on other OSes than Linux? What about Darwin and AIX?
> diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
> index ec068c58aa5..2b2350c53ae 100644
> --- a/gcc/config/rs6000/rs6000.c
> +++ b/gcc/config/rs6000/rs6000.c
> @@ -4911,6 +4911,13 @@ rs6000_option_override_internal (bool global_init_p)
> warning (0, "%qs is deprecated and not recommended in any circumstances",
> "-mno-speculate-indirect-jumps");
>
> + if (TARGET_64BIT)
> + {
> + targetm.min_anchor_offset = -32768;
> + targetm.max_anchor_offset = 32767;
> + targetm.const_anchor = 0x8000;
> + }
Why only on 64 bit? Why these choices?
Segher
