Now that this has been in trunk for a bit with no issues, ok to back port to 10?
Aaron Sawdey, Ph.D. saw...@linux.ibm.com
IBM Linux on POWER Toolchain
> On Jun 3, 2020, at 4:10 PM, Aaron Sawdey <acsaw...@linux.ibm.com> wrote:
>
> This passed regstrap and was approved offline by Segher, posting
> the final form (minus my debug code, oops).
>
> The same problem also arises for plfs where prefixed_load_p()
> doesn't recognize it so we get just lfs in the asm output
> with an @pcrel address.
>
> PR target/95347
> * config/rs6000/rs6000.c (is_stfs_insn): Rename to
> is_lfs_stfs_insn and make it recognize lfs as well.
> (prefixed_store_p): Use is_lfs_stfs_insn().
> (prefixed_load_p): Use is_lfs_stfs_insn() to recognize lfs.
> ---
> gcc/config/rs6000/rs6000.c | 37 +++++++++++++++++++++++++------------
> 1 file changed, 25 insertions(+), 12 deletions(-)
>
> diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
> index ba9069ecc3b..42d517c1f65 100644
> --- a/gcc/config/rs6000/rs6000.c
> +++ b/gcc/config/rs6000/rs6000.c
> @@ -24980,14 +24980,18 @@ address_to_insn_form (rtx addr,
> return INSN_FORM_BAD;
> }
>
> -/* Helper function to see if we're potentially looking at stfs.
> +/* Helper function to see if we're potentially looking at lfs/stfs.
> - PARALLEL containing a SET and a CLOBBER
> - - SET is from UNSPEC_SI_FROM_SF to MEM:SI
> - - CLOBBER is a V4SF
> + - stfs:
> + - SET is from UNSPEC_SI_FROM_SF to MEM:SI
> + - CLOBBER is a V4SF
> + - lfs:
> + - SET is from UNSPEC_SF_FROM_SI to REG:SF
> + - CLOBBER is a DI
> */
>
> static bool
> -is_stfs_insn (rtx_insn *insn)
> +is_lfs_stfs_insn (rtx_insn *insn)
> {
> rtx pattern = PATTERN (insn);
> if (GET_CODE (pattern) != PARALLEL)
> @@ -25013,16 +25017,22 @@ is_stfs_insn (rtx_insn *insn)
> rtx src = SET_SRC (set);
> rtx scratch = SET_DEST (clobber);
>
> - if (GET_CODE (src) != UNSPEC || XINT (src, 1) != UNSPEC_SI_FROM_SF)
> + if (GET_CODE (src) != UNSPEC)
> return false;
>
> - if (GET_CODE (dest) != MEM || GET_MODE (dest) != SImode)
> - return false;
> + /* stfs case. */
> + if (XINT (src, 1) == UNSPEC_SI_FROM_SF
> + && GET_CODE (dest) == MEM && GET_MODE (dest) == SImode
> + && GET_CODE (scratch) == SCRATCH && GET_MODE (scratch) == V4SFmode)
> + return true;
>
> - if (GET_CODE (scratch) != SCRATCH || GET_MODE (scratch) != V4SFmode)
> - return false;
> + /* lfs case. */
> + if (XINT (src, 1) == UNSPEC_SF_FROM_SI
> + && GET_CODE (dest) == REG && GET_MODE (dest) == SFmode
> + && GET_CODE (scratch) == SCRATCH && GET_MODE (scratch) == DImode)
> + return true;
>
> - return true;
> + return false;
> }
>
> /* Helper function to take a REG and a MODE and turn it into the non-prefixed
> @@ -25135,7 +25145,10 @@ prefixed_load_p (rtx_insn *insn)
> else
> non_prefixed = reg_to_non_prefixed (reg, mem_mode);
>
> - return address_is_prefixed (XEXP (mem, 0), mem_mode, non_prefixed);
> + if (non_prefixed == NON_PREFIXED_X && is_lfs_stfs_insn (insn))
> + return address_is_prefixed (XEXP (mem, 0), mem_mode,
> NON_PREFIXED_DEFAULT);
> + else
> + return address_is_prefixed (XEXP (mem, 0), mem_mode, non_prefixed);
> }
>
> /* Whether a store instruction is a prefixed instruction. This is called from
> @@ -25170,7 +25183,7 @@ prefixed_store_p (rtx_insn *insn)
> /* Need to make sure we aren't looking at a stfs which doesn't look
> like the other things reg_to_non_prefixed/address_is_prefixed
> looks for. */
> - if (non_prefixed == NON_PREFIXED_X && is_stfs_insn (insn))
> + if (non_prefixed == NON_PREFIXED_X && is_lfs_stfs_insn (insn))
> return address_is_prefixed (addr, mem_mode, NON_PREFIXED_DEFAULT);
> else
> return address_is_prefixed (addr, mem_mode, non_prefixed);
> --
> 2.17.1
>
